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1 From:WEF SmartBrief <wef@smartbrief.com> Sent:Thursday, April 23, 2026 1:24 PM To:Anderson, Matt Subject:Lake Powell surge will ripple upstream, downstream To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Created for manderso@slocity.org | Web Version April 23, 2026 To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet.WEF SmartBrief The water sector's most relevant news SIGN UP ⋅ SHARE ADVERTISEMENT To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Today's News Lake Powell surge will ripple upstream, downstream Authorities plan to raise Lake Powell's water levels by releasing up to a third of Flaming Gorge Reservoir's water to sustain hydropower, but this could drop Flaming Gorge by up to 27 feet and reduce Lake Mead's power output by 40%. The temporary fix amid ongoing drought will leave downstream reservoirs with lower water levels, including Lake Mead, where the Hoover Dam's power output could drop by 40%. To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet.FLAMING GORGE, WYOMING - OCTOBER 17: The Green River flows into Flaming Gorge Reservoir on October 17, 2023 in Flaming Gorge National Recreation Area, Wyoming. (Photo by RJ Sangosti/MediaNews Group/The Denver Post via Getty Images) The Green River flows into Flaming Gorge Reservoir (RJ Sangosti/MediaNews Group/The Denver Post via Getty Images) Full Story: The Associated Press (4/22) To help protect your privacy, Microsoft Office prevented automatic download of this picture To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. 30% Reduction in Dredging Cost -to-Treat 2 A dredging operation in Texas cut costs and streamlined labor with automation & advanced chemistry. Learn how this two-part solution helped match influent swings in volume and TSS. Read more. ADVERTISEMENT To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Environmental Protection Wastewater sector leads carbon removal shift Wastewater treatment is emerging as a leader in US carbon removal, with help from regulatory requirements and opportunities in infrastructure upgrades. In Virginia's Hampton Roads Sanitation District, startup Crew Carbon will retrofit existing reactors with enhanced alkalinity to improve nutrient management and other processes. Crew has also signed long-term agreements with wastewater facilities nationwide. Full Story: Latitude Media (4/22) To help protect your privacy, Microsoft Office prevented automatic download of this picture Wis. facility to generate energy, protect Miss. River The La Crosse Wastewater Treatment Plant in Wisconsin has completed a five-year, $68 million upgrade, transforming it into a green energy producer and reducing phosphorus levels to 0.05 milligrams per liter. The project will help limit contaminants entering the Mississippi River while generating reusable fertilizer and methane gas. Full Story: WEAU-TV (Eau Claire, Wis.) (4/22) To help protect your privacy, Microsoft Office prevented automatic download of this picture To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Connected Government AI Stop hitting the chatbot ceiling. On May 7th at 1:00 PM EST, learn how a connected platform unifies service delivery and allows your government to operate proactively. Join our peer- validated scaling session. Register now! ADVERTISEMENT To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Circular Water Economy 3 Sustainable winemaking accelerates at US wineries The sustainable winemaking movement has seen significant growth across the country, with California producing around 90% of its wine in certified sustainable wineries and 65% of its vineyards now certified. Other states, including Washington, Oregon and New York, have also expanded their certified sustainable winery presence, reflecting a nationwide embrace of environmentally responsible viticulture. Wineries are adopting practices like solar power, water recycling, biodynamic farming and lighter packaging to reduce their ecological footprint and support the long-term health of their vineyards. Full Story: Food & Wine (4/22) To help protect your privacy, Microsoft Office prevented automatic download of this picture To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Citizen Support That Holds Up Serving your residents is getting harder than ever. Join our live panel webinar to hear real-world lessons on using AI chatbots and NLP to automate 311 inquiries, reduce wait times, and improve experiences while maintaining transparency. Register now for April 23! ADVERTISEMENT Featured Content Sponsored Content from Netline 15 AI Mistakes CEOs Make and How to Avoid Them: A Guide to Human - Centered Technology Implementation Create Your Dream Work All Things Innovation Releases AI-Driven Innovation & Insights Solutions Showcase Management Series: What do All Great Managers Have in Common Stay Interviews: Why And How To Use Them Successfully Infrastructure Watch Fla. county begins $1.2B wastewater system 4 Hillsborough County, Fla., has started the $1.2 billion One Water South project, which includes an advanced water resource recovery facility, a high-capacity pump station and a pipeline network to manage wastewater and reclaimed water. Officials say the facility will meet regional demand through 2050 and support environmental management and population growth. Full Story: Tampa Bay Business & Wealth (St. Petersburg, Fla.) (4/2026) To help protect your privacy, Microsoft Office prevented automatic download of this picture Water Supply How Texas proposal would close supply -demand gap A draft water plan from the Texas Water Development Board projects a 10% decline in water supply and a 6% increase in demand over a 50-year horizon. Developed from 16 regional plans, the draft aims to close the supply-demand gap by implementing 3,000 water-management projects, with a focus on surface water development, conservation and reuse. Full Story: Smart Water Magazine (4/22) To help protect your privacy, Microsoft Office prevented automatic download of this picture Water Environment Research Read more from Water Environment Research (WER) here. To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.Most recent headlines To help protect your privacy, Microsoft Office prevented automatic download of this picture Fluoride Sources and Enrichment Mechanisms in a Coastal Plain Under the Influence of Seawater Intrusion (4/23) Utilization of Chalcone for Targeted Removal of Azo Dye From Wastewater (4/23) Implication of Rheological and Thermal Properties of Sludge for Energy Optimization in a Sludge Treatment Train Incorporating Thermal Hydrolysis and Anaerobic Digestion (4/22) Funding and Financing EPA funding cut proposal could slow water projects Cuts to Environmental Protection Agency funding could reduce the State Revolving Funds for water projects by more than 90%. Utilities rely on SRF loans to move projects from design to 5 construction, and tighter funding queues could extend delivery timelines, increase exposure to cost escalation and force utilities to defer or resize projects. Full Story: Water Daily (4/19) To help protect your privacy, Microsoft Office prevented automatic download of this picture Stormwater Northeast Ohio to begin final Lake Erie sewer tunnel The Northeast Ohio Regional Sewer District is set to begin construction on the final major tunnel of a decades-long, $3 billion project to prevent sewage overflows into Lake Erie. The tunnel, part of a federal mandate to address combined sewer systems, will span several miles and significantly reduce annual discharges into the lake. Full Story: Underground Infrastructure (4/2026) To help protect your privacy, Microsoft Office prevented automatic download of this picture Research, Innovation & Technology Robots help clean up Port of Los Angeles Robots are working on cleaning up the Port of Los Angeles, with plans calling for them to remove tons of trash in the coming months. The robots from Clean Earth Rovers are semi-autonomous and operate like vacuum cleaners on the water, with each capable of picking up 200 pounds of trash. Full Story: KABC-TV (Los Angeles) (4/22) To help protect your privacy, Microsoft Office prevented automatic download of this picture Workforce MMSD's Schultheis discusses watershed management Episode 189 of the ASCE Plot Points podcast features Kristin Schultheis in conversation with guest hosts Brianne Duncan and Wendy Cohen from the ASCE Environmental and Water Resources Institute's Environmental Health and Water Quality Committee. The episode delves into the intricacies of watershed management, highlighting the importance of cross-disciplinary dialogue in addressing both urban and rural water challenges. Full Story: American Society of Civil Engineers (4/21) To help protect your privacy, Microsoft Office prevented automatic download of this picture 6 Question of the Day POP QUIZ: Wash. State University researchers have used high temperatures, oxygenated pretreatment and what else to turn biosolids into 99% pure methane? Hint: Check out yesterday's SmartBrief. Stay tuned for the results in tomorrow's SmartBrief. UV light Patented bacteria Anaerobic digestion Mechanical vapor recompression Today at WEF The primary reference for nutrient management Activated Sludge and Nutrient Removal, MOP OM-9, is the primary reference for nutrient management! Expanded content in the new edition includes an updated process control section with step-by-step examples for calculations, a new laboratory chapter with detailed directions for common process control tests and an introduction to using modeling for process control. Get your copy today! To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.The primary reference for nutrient management (WEF) To help protect your privacy, Microsoft Office prevented automatic download of this picture Help the WE&T team improve Operator Essentials Operator Essentials is a long-running section in WE&T magazine that equips frontline operators with need-to-know tips and resources to learn more about the work they perform each day as well as stay ahead of emerging topics. If you are familiar with the Operator Essentials section, please take this 5-minute survey to help WEF's Operator Essentials Focus Group better meet reader needs. To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.WEF (WEF) To help protect your privacy, Microsoft Office prevented automatic download of this picture 7 LEARN MORE ABOUT WEF: WEF Home | Join WEF | Member News | WEFTEC | Career Center Online Library | Events | Advocacy | Bookstore In Case You Missed It Biosolid treatment pilot produces 99% pure methane Interesting Engineering (4/22) Carollo to manage building of first reuse facility in Nev. WaterWorld (4/21) Idaho city to add CO2 system to treatment facility Idaho Capital Sun (Boise) (4/22) WEF SmartBrief is a daily news digest produced by SmartBrief, Inc., for WEF. Got this from a friend? Subscribe now and stay in the loop! Sign Up To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.SmartBrief Future Follow SmartBrief To help protect your To help protect your Contact Us: Feedback | Advertise Sign Up | Update Profile | Advertise with SmartBrief Unsubscribe | Privacy Policy 8 Copyright © 2026 SmartBrief. All Rights Reserved. A division of Future US LLC. Full 7th Floor, 130 West 42nd Street, New York, NY, 10036. 9 From:WEF SmartBrief <wef@smartbrief.com> Sent:Thursday, April 16, 2026 1:20 PM To:Anderson, Matt Subject:Water reliability matches inflation as priority for voters | Microbiologist honored for pioneering water-reuse safety | Filter removes up to 98.5% of microplastics from water To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Created for manderso@slocity.org | Web Version April 16, 2026 To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet.WEF SmartBrief The water sector's most relevant news SIGN UP ⋅ SHARE ADVERTISEMENT To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Today's News Water reliability matches inflation as priority for voters US voters consider reliable access to water as important as inflation and cost of living, according to a Value of Water Campaign survey conducted in February. The poll of more than 1,000 voters reveals concerns about the affordability and safety of water, with 69% of respondents expressing worry about their drinking water, and 78% supporting increased state and local investment in water infrastructure. Full Story: Water Online (4/15) To help protect your privacy, Microsoft Office prevented automatic download of this picture To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. SEWER BREAK RESOLVED, STABILITY RESTORED 10 After an emergency call to fix a Florida sewer break, Fortiline had everything ready to ship overnight. The district's utility director called the effort "Phenomenal. In just 3 days, we accomplished what would typically require over 2 weeks' work". LEARN MORE ADVERTISEMENT To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Environmental Protection Ill. city admits to violating Clean Water Act East St. Louis, Ill., has taken responsibility for Clean Water Act violations in an interim agreement with the Environmental Protection Agency, the state and the Justice Department. The city has admitted to nine violations stemming from improper wastewater operation that resulted in leakage into local waterways. It must submit a long-term compliance plan by June 30, 2027. Full Story: KTVI-TV (St. Louis) (4/13) To help protect your privacy, Microsoft Office prevented automatic download of this picture EPA honors infrastructure projects financed by state revolving funds WaterWorld (4/15) To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Citizen Support That Holds Up Serving your residents is getting harder than ever. Join our live panel webinar to hear real-world lessons on using AI chatbots and NLP to automate 311 inquiries, reduce wait times, and improve experiences while maintaining transparency. Register now for April 23! ADVERTISEMENT Circular Water Economy Microbiologist honored for pioneering water -reuse safety Microbiologist Joan Bray Rose has received the Lee Kuan Yew Water Prize for her development of quantitative microbial risk assessment, a tool that measures infection risks from microbes in 11 water that has been instrumental in ensuring the safety of water reuse systems. Rose is known for her research on Cryptosporidium, which caused a fatal outbreak in Milwaukee in 1993. Full Story: The Straits Times (Singapore) (4/16) To help protect your privacy, Microsoft Office prevented automatic download of this picture To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Boost AI data cloud results effortlessly Discover how top media and advertising experts enhance their ROI through AI-ready data integration. Dive into powerful analytics and data agents on April 29 at Accelerate, Snowflake's annual virtual program. Learn the secrets to campaign success. Register now! ADVERTISEMENT To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Free eBooks and Resources Free eBooks and resources brought to you by our sponsors Nonverbal Communications Skills -- The 10 Skills You Need to Learn 70+ Excel Keyboard Shortcuts for Windows (Free Cheat Sheet) Best Practices for Email Etiquette 11 Habits That Will Give You A Complete And Successful Life Creating Positive Habits - The Ultimate Guide Infrastructure Watch Facility captures methane to create electricity A Michigan wastewater facility captures methane from biosolid processing to power its operations and send excess electricity to the grid. The $9.4 million combined power and heat system at the Benton Harbor-St. Joseph Joint Wastewater Treatment Plant includes two 1- million-gallon digesters, a biogas cleaning unit and two generators. Additionally, heat generated by the system is recaptured to warm the digesters, reducing reliance on traditional boilers and maximizing overall energy use. Full Story: The Herald-Palladium (St. Joseph, Mich.) (4/16) 12 To help protect your privacy, Microsoft Office prevented automatic download of this picture Water Environment Research Read more from Water Environment Research (WER) here. To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.Most recent headlines To help protect your privacy, Microsoft Office prevented automatic download of this picture Eco-Friendly Synthesis of CdO Photocatalyst: Tuning Structural, Morphological, and Optical Characteristics via Calcination Temperature (4/16) Impact of Ultraviolet Radiation on the Growth Dynamics of Toxic and Nontoxic Microcystis aeruginosa (4/16) Modeling Method for A2O Anoxic Zone Based on PSO -SCN (4/15) Funding and Financing Calif. district advances budget with $1B for water needs The Metropolitan Water District of Southern California has approved a two-year budget that includes more than $1 billion for capital investment to address aging infrastructure and ensure water supply reliability for years to come. The budget calls for $150 million for the Pure Water Southern California program, which aims to produce up to 45 million gallons of recycled water per day. Full Story: Underground Infrastructure (4/2026) To help protect your privacy, Microsoft Office prevented automatic download of this picture Pa. allocates $284M for water infrastructure Pennsylvania has allocated $284.2 million to water infrastructure projects in 20 counties, funded through the Pennsylvania Infrastructure Investment Authority. Projects include $53.9 million for the Pittsburgh Water and Sewer Authority to rehabilitate collection systems, $20 million for the Everett Area Municipal Authority to build a water resource recovery facility and $15.3 million for the Southwestern Cambria County Water Authority to install waterlines and a storage tank. Full Story: Smart Water Magazine (4/16) To help protect your privacy, Microsoft Office prevented automatic download of this picture 13 Stormwater Milwaukee releases combined sewer overflow Milwaukee's Metropolitan Sewerage District has initiated its first combined sewer overflow of the year amid up to 5 inches of rain over three days. In addition, the district is investigating five isolated-sewer overflows in Bayside, Milwaukee and River Hills, and has asked residents to limit water usage to minimize the effect on Lake Michigan and other local water bodies. Full Story: Milwaukee Journal Sentinel (tiered subscription model) (4/15) To help protect your privacy, Microsoft Office prevented automatic download of this picture $28M project to keep rain out of wastewater facility Grand Rapids, Mich., officials are planning a $28 million project to separate stormwater and wastewater, replacing a combined system and rerouting rainfall runoff away from the Water Resource Recovery Facility to the Grand River. The project is expected to reduce strain on the facility and also replace curbs, pavement and sidewalks. Full Story: MLive (Michigan) (tiered subscription model) (4/15) To help protect your privacy, Microsoft Office prevented automatic download of this picture Mich. facility discharges partially treated wastewater amid heavy rain WILX-TV (Lansing/Jackson, Mich.) (4/15) Research, Innovation & Technology Filter removes up to 98.5% of microplastics from water A textile-based filter has removed as much as 98.5% of microplastics from water in field tests in a municipal wastewater facility and an industrial laundry, say researchers at the German Institutes of Textile and Fiber Research Denkendorf. The cascade filter captures particles as small as 1.5 microns, using a three-stage system built from 3D sandwich structures of polypropylene fabric and spacer layers. To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet.Filter removes up to 98.5% of microplastics from water (Svetlozar Hristov/Getty Images) Full Story: Interesting Engineering (4/15) To help protect your privacy, Microsoft Office prevented automatic download of this picture Workforce Provide communication training to reengage your managers Manager engagement has seen a sharp decline, dropping from 31% in 2022 to just 22% in 2025, according to Gallup data, and Ketchum's Lauren Butler attributes the slump to expanding 14 managerial roles and insufficient support, emphasizing that engaged managers are essential for cultivating organizational culture. "Managers are the most trusted communications channel -- and the least trained to be communicators. Providing managers with resources and training to communicate consistently with clarity, empathy and confidence is foundational," Butler says. Full Story: Ragan (4/14) To help protect your privacy, Microsoft Office prevented automatic download of this picture Question of the Day POP QUIZ: University of Illinois researchers used graphics processing units to forecast what in near real time? Hint: Check out yesterday's SmartBrief. Stay tuned for the results in tomorrow's SmartBrief. Droughts Earthquakes Markets Floods Today at WEF Turn wastewater into opportunity with resource recovery Unlock the future of wastewater management with the Resource Recovery Handbook. Discover how circular water economy principles can help your utility recover water, nutrients, energy and biosolids -- benefiting your organization and your community. Get practical guidance, financial strategies, and technology insights from industry experts. To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.Turn wastewater into opportunity with resource recovery (WEF) To help protect your privacy, Microsoft Office prevented automatic download of this picture Save on registration for Industrial Water Solutions 2026 From manufacturing to artificial intelligence and energy independence, water is the fuel of the new economy. The 2026 Industrial Water Solutions conference, co-hosted by WEF and the WateReuse To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.WEF (WEF) 15 Association, will convene business and utility leaders, June 8-10 in Chicago, to envision circular water solutions that recover resources, minimize waste and unlock new value from water across the industrial lifecycle. Register by TOMORROW, April 17, to take advantage of early-bird savings. To help protect your privacy, Microsoft Office prevented automatic download of this picture LEARN MORE ABOUT WEF: WEF Home | Join WEF | Member News | WEFTEC | Career Center Online Library | Events | Advocacy | Bookstore WEF SmartBrief is a daily news digest produced by SmartBrief, Inc., for WEF. Got this from a friend? Subscribe now and stay in the loop! Sign Up To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.SmartBrief Future Follow SmartBrief To help pr otect yo ur To help pr otect yo ur Contact Us: Feedback | Advertise Sign Up | Update Profile | Advertise with SmartBrief Unsubscribe | Privacy Policy Copyright © 2026 SmartBrief. All Rights Reserved. A division of Future US LLC. Full 7th Floor, 130 West 42nd Street, New York, NY, 10036. 16 From:Andrea Magana <amagana@zalcolabs.com> Sent:Monday, March 9, 2026 11:37 AM To:Anderson, Matt Cc:Juan Magana Subject:RE: Quote Request and W-9 Request Attachments:City of San Luis Obispo (Matt Anderson).pdf; Zalco W-9.pdf; Copy of COC DOC-ADM-100 2025-11-12.xlsm Good morning Matt, Attached is pricing, W-9, and COC. I have provided pricing per sample for a Standard TAT and 5 business days. Let me know if you have any questions regarding the quote. Contact me if you have any quesƟons or concerns. Andrea Magana Office Administrator Zalco Laboratories,Inc 4309 Armour Ave, Bakersfield,CA 93308 Office: (661)395-0539 Website: www.zalcolabs.com amagana@zalcolabs.com This e-mail, including aƩachments, contains informaƟon that is privileged, proprietary, non-public, confidenƟal, trademarked, copyrighted or exempt from disclosure and is intended to be conveyed only to the designated recipients. If you are not the intended recipient, please delete this e-mail, including aƩachments, and do not disseminate, distribute or copy this communicaƟon by e-mail or otherwise. The unauthorized use, disseminaƟon, distribuƟon or reproducƟon of this e-mail, including aƩachments, is prohibited and may be unlawful. We reserve the right to monitor and review the content of all messages From: Anderson, Matt <manderso@slocity.org> Sent: Friday, March 6, 2026 9:49 AM To: amagana@valcolabs.com <amagana@valcolabs.com> Subject: Quote Request and W-9 Request Good morning Andrea, I hope all is well this Friday. I just had the opportunity to speak with Ashley and she recommended that I follow up with an email. We, the City of San Luis Obispo's Wastewater facility, have been notified by our local landfill that they will not 17 accept any additional solids until we provide test results for the constituents listed below. Could you send a quote for a 3 - day rush (if possible) and a 5-day rush (if possible) for the following? The W-9 request will allow our purchasing department to add Valco as a vendor. Locations - 2, Wash Press Screenings, Fine Screens Constituents - CAM 17 metals, VOC 8260, pesticides EPA 8081, and for PCB's EPA 8082A I have multiple unpreserved 8 ounce jars and figure we can overnight the samples to you. Thanks, Matt Anderson Laboratory Manager To help protect your priv acy, Microsoft Office prevented automatic download of this picture from the Internet.City of San Luis Obispo Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications Project ID: COMPANY CONTACT PHONE (10 Business Days) ADDRESS AP/Email Report E-mail SAMPLER (SIGNATURE) X DATE SAMPLED Date: Time: Received By: Date: Time: NOTE:Samples Discarded 30 days after results unless other Sample Type Key:NP-Non-Potable; BS-Biosolid; DW-Drinking Water; GW-Groundwater; G-Gas arrangements are made. Hazardous samples will be returned to client LPG-Liquid Petroleum Gas; OL-Oil; P-Petroleum; S-Solid/Soil; ST-Storm water or disposed of at client's expense. WW-Wastewater; L-Liquid; Aq-Aqueous System# ANALYSIS REQUESTED PO: CHAIN OF CUSTODY, ID# CLIP: (DIST/PERSON) EMAIL: EDT:Type of Container (s)Number of ContainersChlorine ResidualField Temperature °CClient Declined State Submittal Rush By: Turnaround Time: Working Days Sample MatrixRoutine: Received Temp: C°LAB # ZALCO LABORATORIES, INC. 4309 Armour Avenue, Bakersfield, CA 93308 Phone: (661) 395-0539 Website: www.zalcolabs.com SAMPLE DESCRIPTION TIME SAMPLED Company: Relinquished By: NOTES: DOC-ADM-100 Rev 4 06/28/2024 Company: 18 From:Clancy, Daniel Sent:Wednesday, January 21, 2026 9:14 AM To:Lehman, Haley Subject:RE: Biosolids RFP No, I meant to include Chris. Sorry.. I should have proofread.. gah. Now you know about the biosolid RFP lucky you! From: Lehman, Haley <HLehman@slocity.org> Sent: Wednesday, January 21, 2026 8:14 AM To: Clancy, Daniel <dclancy@slocity.org> Subject: Re: Biosolids RFP Did you mean to include me or a different Haley? Haley Lehman Technology Project Manager Information Technology Information Technology Services 990 Palm Street, San Luis Obispo, CA 93401-3249 E HLehman@slocity.org T 805.781.7052 C 805.788.8667 slocity.org Stay connected with the City by signing up for e-notifications From: McGrath, Patrick <pmcgrath@slocity.org> Sent: Tuesday, January 20, 2026 5:29 PM To: Clancy, Daniel <dclancy@slocity.org>; Lehman, Haley <HLehman@slocity.org>; Scott, Shawna <sscott@slocity.org>; Lehman, Chris <clehman@slocity.org> Subject: Re: Biosolids RFP Looping in Chris (sup Hayley!). $85/ton at E&G vs. $110/ton at Synagro. Tradition continues! Get Outlook for iOS From: Clancy, Daniel <dclancy@slocity.org> Sent: Tuesday, January 20, 2026 5:25:38 PM 19 To: McGrath, Patrick <pmcgrath@slocity.org>; Lehman, Haley <HLehman@slocity.org>; Scott, Shawna <sscott@slocity.org> Subject: Biosolids RFP Hi, Two bids were received today. See here: Bids I thought we’d get something from Patriot but they didn’t submit on BidNet or email me. Daniel Clancy Financial Analyst Finance Finance Operations 990 Palm, San Luis Obispo, CA 93401-3249 E DClancy@slocity.org T 805.781.7510 slocity.org Stay connected with the City by signing up for e-notifications 22 From:Anderson, Matt Sent:Thursday, November 20, 2025 3:50 PM To:Christine Wong Subject:RE: Request for Proposal - Review, Discuss, Edit SIU Permits Attachments:Order R3-2024-0001 (4).pdf; TSO R3-2024-0021 (1).pdf Christine, Looking forward to tomorrow, but on a separate note, I am also requesting proposals for our 2026 Local Limits study. The TSO states that we must submit the plan by 5/1/26 and initiate sampling by 11/1/26. In reality, we would most likely want to begin sampling in September or October when Cal Poly is in session and before the wet season. If this proposal is doable, I would prefer the scope to include the following: drafting the local limits sampling and analysis plan, drafting the Local Limits report, and updating other local limits (TSO related constituents). At this time, I will procure the contract lab services in a separate quote/purchase order. Thanks, Matt Anderson Laboratory Manager Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications From: Christine Wong <cwong@algcorp.com> Sent: Thursday, November 20, 2025 12:21 PM To: Anderson, Matt <manderso@slocity.org> Cc: Melby, Jordan <JMelby@slocity.org> Subject: RE: Request for Proposal - Review, Discuss, Edit SIU Permits Hi Matt, Sure thing, sounds like a good fit. Cheers, ~Christine From: Anderson, Matt <manderso@slocity.org> Sent: Thursday, November 20, 2025 10:30 AM 23 To: Christine Wong <cwong@algcorp.com> Cc: Melby, Jordan <JMelby@slocity.org> Subject: RE: Request for Proposal - Review, Discuss, Edit SIU Permits Good morning Christine, Let’s add another item for tomorrow’s agenda – we have flip flopped on how we permit automotive businesses, we de- permitted some, and now our director has given us direction to permit them all. In the scope, can we add the review of our current Class I IU’s and a recommendation on how to best define a Class I? Thanks, Matt From: Christine Wong <cwong@algcorp.com> Sent: Wednesday, November 19, 2025 12:04 PM To: Anderson, Matt <manderso@slocity.org> Cc: Melby, Jordan <JMelby@slocity.org> Subject: RE: Request for Proposal - Review, Discuss, Edit SIU Permits Hi Matt, Works for me, I just sent an invitation. Talk to you on Friday, ~Christine From: Anderson, Matt <manderso@slocity.org> Sent: Wednesday, November 19, 2025 11:40 AM To: Christine Wong <cwong@algcorp.com> Cc: Melby, Jordan <JMelby@slocity.org> Subject: RE: Request for Proposal - Review, Discuss, Edit SIU Permits Christine, Can we book 1pm on Friday? Matt From: Christine Wong <cwong@algcorp.com> Sent: Wednesday, November 19, 2025 8:30 AM To: Anderson, Matt <manderso@slocity.org> Subject: RE: Request for Proposal - Review, Discuss, Edit SIU Permits Good Morning, Matt: That sounds perfectly reasonable. Let’s chat through the details – I’m free this afternoon, tomorrow morning before 11 AM, and Friday afternoon. Please let me know when you’re available and we can get a time on the schedule. Cheers, ~Christine In oƯice on Tuesdays and Thursdays, at other times please call on my cell phone. 24 Christine Wong | Senior Environmental Scientist OƯice: 805.764.6019 Cell: 571.232.5722 601 E. Daily Dr. Ste. 302 Camarillo CA 93010 cwong@algcorp.com | www.algcorp.com This message contains information which may be confidential and privileged. Unless you are the addressee (or authorized to receive for the addressee), you may not use, copy or disclose to anyone the message or any information contained in the message. If you have received the message in error, please advise the sender by reply e-mail and delete the message. From: Anderson, Matt <manderso@slocity.org> Sent: Tuesday, November 18, 2025 4:31 PM To: Christine Wong <cwong@algcorp.com> Subject: RE: Request for Proposal - Review, Discuss, Edit SIU Permits Christine, Hopes and dreams – over Teams/Zoom we hear the professional’s opinion and comb through the good and bad of our existing SIU permits. And transition to either a new format that would be ‘more’ EPA compliant or just a better path forward. The vision would be to improve the existing permits and create learning opportunities for the entire team. Kind of out there, but we can follow up with a call. Send me some times that work for you this week. Thanks, Matt Anderson Laboratory Manager Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications From: Christine Wong <cwong@algcorp.com> Sent: Tuesday, November 18, 2025 2:35 PM To: Anderson, Matt <manderso@slocity.org> Subject: RE: Request for Proposal - Review, Discuss, Edit SIU Permits Hi Matt, Great to hear from you! We’re happy to prepare a proposal for assistance with SIU permits. Can you give us an idea of the specific scope you were thinking of? For example, are you looking to overhaul your permits and draft a new permit 25 template? Or more along the lines of reviewing and tweaking your current permits? I’m happy to chat through your ideas if you’d like to discuss – please let me know when would be a good time. Cheers, ~Christine In oƯice on Tuesdays and Thursdays, at other times please call on my cell phone. Christine Wong | Senior Environmental Scientist OƯice: 805.764.6019 Cell: 571.232.5722 601 E. Daily Dr. Ste. 302 Camarillo CA 93010 cwong@algcorp.com | www.algcorp.com This message contains information which may be confidential and privileged. Unless you are the addressee (or authorized to receive for the addressee), you may not use, copy or disclose to anyone the message or any information contained in the message. If you have received the message in error, please advise the sender by reply e-mail and delete the message. From: Anderson, Matt <manderso@slocity.org> Sent: Tuesday, November 18, 2025 12:58 PM To: Christine Wong <cwong@algcorp.com> Subject: Request for Proposal - Review, Discuss, Edit SIU Permits Christine, I hope all is well this Tuesday. We are starting to catch up and address areas for program improvements with professional review and editing of the existing permits being our next target. We would like to work with you as we review, edit, and ultimately improve our 6 existing SIU permits. Feel free to give me a call to discuss or send an email. Thanks, Matt Anderson Laboratory Manager Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101, San Luis Obispo, California 93401 Phone (805) 549-3147 Fax (805) 543-0397 Central Coast Regional Water Quality Control Board (http://www.waterboards.ca.gov/centralcoast) ORDER R3-2024-0001 NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT NUMBER CA0049224 WASTE DISCHARGE REQUIREMENTS FOR THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY The following Discharger is subject to waste discharge requirements set forth in this Order: Discharger City of San Luis Obispo Name of Facility Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Table 1. Discharge Location Discharge Point Effluent Description Discharge Point Latitude (North) Discharge Point Longitude (West) Receiving Water 001 Tertiary treated domestic wastewater 35.244307° 120.680618° San Luis Obispo Creek 002 Disinfected Tertiary Recycled Municipal Wastewater - - Reclamation Use This Order was adopted on: June 20, 2024 This Order shall become effective on: September 1, 2024 This Order shall expire on: August 31, 2029 The Discharger shall file a Report of Waste Discharge as an application for reissuance of waste discharge requirements in accordance with title 23, California Code of Regulations and an application for reissuance of a National Pollutant Discharge CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 2 Elimination System permit no later than 180 days prior to the Order expiration date. The U.S. Environmental Protection Agency and the California Regional Water Quality Control Board, Central Coast Region have classified this discharge as follows: Major discharge. I, Ryan E. Lodge, Executive Officer, do hereby certify that this Order with all attachments is a full, true, and correct copy of an order adopted by the California Regional Water Quality Control Board, Central Coast Region on the date indicated above. Ryan E. Lodge, Executive Officer CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 3 TABLE OF CONTENTS 1. FACILITY INFORMATION .......................................................................................... 4 2. FINDINGS ................................................................................................................... 4 3. DISCHARGE PROHIBITIONS .................................................................................... 7 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS ................................. 7 4.1. Effluent Limitations – Discharge Point 001 ........................................................ 7 4.2. Land Discharge Specifications – Not Applicable ............................................. 11 4.3. Recycling Specifications – Discharge Point 002 ............................................. 11 5. RECEIVING WATER LIMITATIONS ......................................................................... 12 5.1. Surface Water Limitations ............................................................................... 12 5.2. Groundwater Limitations ................................................................................. 16 6. PROVISIONS ............................................................................................................ 17 6.1. Standard Provisions ........................................................................................ 17 6.2. Monitoring and Reporting Program (MRP) Requirements ............................... 17 6.3. Special Provisions ........................................................................................... 17 7. COMPLIANCE DETERMINATION ............................................................................ 23 TABLE OF TABLES Table 1. Discharge Location ............................................................................................ 1 Table 2. Effluent Limitations at Discharge Point 001 ....................................................... 8 Table 3. Organic Substances Water Quality Criteria ..................................................... 14 Table 4. Hardness Dependent Metals Criteria .............................................................. 15 Table 5. Annual Mean Surface Water Quality Objectives .............................................. 15 Table 6. Groundwater Objectives .................................................................................. 17 TABLE OF ATTACHMENTS ATTACHMENT A – DEFINITIONS ...............................................................................A-1 ATTACHMENT B – MAP ..............................................................................................B-1 ATTACHMENT C – FLOW SCHEMATIC .................................................................... C-1 ATTACHMENT D – STANDARD PROVISIONS ......................................................... D-1 ATTACHMENT E – MONITORING AND REPORTING PROGRAM ............................E-1 ATTACHMENT F – FACT SHEET ............................................................................... F-1 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 4 1. FACILITY INFORMATION Information describing the City of San Luis Obispo (Discharger) Water Resource Recovery Facility (Facility) is summarized on the cover page and in sections 1 and 2 of the Fact Sheet (Attachment F). Section 1 of the Fact Sheet also includes information regarding the Facility’s permit application. 2. FINDINGS The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 2.1. Legal Authorities. This Order serves as waste discharge requirements (WDRs) pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA) and implementing regulations adopted by the United States Environmental Protection Agency (U.S. EPA) and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as a National Pollutant Discharge Elimination System (NPDES) permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1 subject to the WDRs in this Order. 2.2. Background and Rationale for Requirements. The Central Coast Water Board developed the requirements in this Order based on information submitted as part of the application, through monitoring and reporting programs, and other available information. The Fact Sheet (Attachment F), which contains background information and rationale for the requirements in this Order, is hereby incorporated into and constitutes Findings for this Order. Attachments A through E are also incorporated into this Order. 2.3. Provisions and Requirements Implementing State Law. Some provisions/requirements in this Order are included to implement state law only . These provisions/requirements are not required or authorized under the federal CWA; consequently, violations of these provisions/requirements are not subject to the enforcement remedies that are available for NPDES violations. 2.4. Water Reclamation Requirements for Recycled Water Production and Use. This Order allows the production and use of disinfected secondary and tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements established by the California Department of Public Health in title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. Additionally, this Order includes water reclamation requirements for the Facility pursuant to the State Water Resources Control Board’s (State Water Board’s) Division of Drinking Water (DDW) recommendations submitted to the Central Coast Water Board. The distribution and offsite reuse of recycled water produced by the Facility is subject to the State Water Board’s General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW), or other applicable permit, dependent on final use. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 5 2.5. Response to Climate Change. Climate change refers to observed changes in regional weather patterns such as temperature, precipitation, and storm frequency and size. At the local scale, within urbanized areas, climate change may directly impact groundwater and surface water supply; drainage, flooding, and erosion patterns; and ecosystems and habitat. This shift in climate, combined with California’s growing population, has increased reliance on pumping, conveying, treating, and heating water, increasing the water sector’s greenhouse gas emissions. The State Water Board’s Resolution 2017 -0012, Comprehensive Response to Climate Change, requires a proactive response to climate change in all California Water Board actions, with the intent to embed climate change consideration into all programs and activities. Aligning with Resolution 2017 -0012, this Order supports the beneficial reuse of the Facility’s treated effluent to offset potable water supplies for irrigation and dedicated in -stream flows to support critical creek habitat. This Order incorporates requirements for the Facility to beneficially reuse treated effluent, which serves to diversify the State’s water supply portfolio to prepare for uncertainties in water resources due to the changing climate through ongoing implementation, monitoring, and updating of the Discharger’s climate action planning efforts using the best available data and technology for wastewater treatment and operation. In 2019, the City participated in the development of the Multi-Jurisdictional San Luis Obispo Hazard Mitigation, a planning effort that identifies and prioritizes the City’s vulnerability to hazards and outlines mitigation goals and objectives. In August 2020, the City adopted its Climate Action Plan with goals for community -wide carbon neutrality by 2035. Most recently, on January 17, 202 3, The City adopted the Climate Adaptation and Safety Element as part of its general plan. According to Disaster Mitigation Act (DMA) requirement §201.6(d)(3), the City must review and revise this plan within five years for continued mitigation project grant funding. Additionally, the City is currently undergoing construction of the SLO Water Plus project, which includes Facility upgrades to improve the Facility’s energy efficiency, provide flood protection improvements, increase treatment capacity, and improve resource recovery. To incorporate proactive planning for the future, this Order requires the Discharger to report on implementation progress, monitoring, and planning updates at this Facility as it relates to flooding, wildfire, renewable energy generation and energy efficiency, temperature, water recycling, biosolid s reuse, and influent flow and loading fluctuations exacerbated by climate change. 2.6. Human Right to Water. California Water Code section 106.3 established the policy that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. On January 26, 2017, the Central Coast Water Board adopted Resolution R3 -2017- 0004, which adopts the human right to water as a core value and affirms the realization of the human right to water and protecting human health as the Central Coast Water Board's top priorities. Consistent with the human right to water stated in California Water Code section 106.3, subdivision (a), and the Central Coast Water Board’s Resolution R3-2017-0004, this Order promotes actions that advance the human right to water and discourages actions that delay or impede opportunities for communities to secure safe, clean, affordable, and accessible CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 6 water adequate for human consumption, cooking, and sanitary purposes. This Order implements recently updated mercury water quality objectives that are more stringent than previous objectives to more adequately protect beneficial uses related to water and fish consumption. 2.7. Disadvantaged Community Status. Environmental Justice principles call for the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income in the development, adoption, implementation, and enforcement of all environmental laws, regulations, and policies that affect every community’s natural resources and the places people live, work, play, and learn. The Central Coast Water Board implements regulatory activities and water quality projects in a manner that ensures the fair treatment of all people, including Underrepresented Communities. Underrepresented Communities include but are not limited to Disadvantaged Communities (DACs), Severely Disadvantaged Communities (SDACs), Economically Distressed Areas (EDAs), Tribes, Environmentally Disadvantaged Communities (EnvDACs), and members of Fringe Communities.1 Furthermore, the Central Coast Water Board is committed to providing all stakeholders the opportunity to participate in the public process and provide meaningful input to decisions that affect communities. To meet environmental justice principles, staff has evaluated the disadvantaged community status for the Discharger. Using 2020 census data, the California Department of Water Resources Disadvantaged Community (DAC) Mapping Tool1 identifies 16 block groups in the City of San Luis Obispo, representing approximately 54 percent of the population, as disadvantaged communities. The tool defines a DAC as a census block with a median household income between $50,458 and $67,278 and a severely disadvantaged community (SDAC) as a census block with a median household income below $50,458. The SDAC census blocks in the City of San Luis Obispo have median household incomes of $8,075, $9,596, $11,935, $28,173, $28,284, $35,774, $39,526, and $44,167. The DAC census blocks in the City of San Luis Obispo have median household income of $51,074, $52,961, $55,769, $56,866, $57,175, $57,803, $58,083, and $60,417. 2.8. Notification of Interested Persons. The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provided them with an opportunity to submit their written comments and recommendations. Details of the notification are provided in the Fact Sheet, Attachment F. 2.9. Consideration of Public Comment. The Central Coast Water Board, in a public meeting, heard and considered all comments pertaining to the discharge. Details of the public hearing are provided in the Fact Sheet, Attachment F. THEREFORE, IT IS HEREBY ORDERED that this Order supersedes Order R3-2014- 0033, except for enforcement purposes, that Waste Discharge/Master Reclamation 1 The DAC Mapping Tool is used to inform statewide Integrated Water Resources Management (IRWM), Sustainable Groundwater Monitoring Act (SGMA), and California Water Plan implementation efforts and can be found at the following website: https://gis.water.ca.gov/app/dacs/. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 7 Requirements Order R3-2003-081 is terminated upon Discharger’s enrollment in State Water Board Order WQ-2016-0068-DDW, except for enforcement purposes, and, in order to meet the provisions contained in division 7 of the California Water Code (commencing with section 13000) and regulations adopted thereunder and the provisions of the CWA and regulations and guidelines adopted thereunder, the Discharger shall comply with the requirements in this Order. This action in no way prevents the Central Coast Water Board from taking enforcement action for violations of the previous orders. 3. DISCHARGE PROHIBITIONS 3.1. Discharge of treated wastewater at a location or in a manner other than as described by this Order at Discharge Points 001 and 002, with compliance measured at EFF-001 and EFF-002 respectively as described in the Monitoring and Reporting Program (MRP) Attachment E, is prohibited. 3.2. The discharge of any waste not specifically regulated by this Order, excluding stormwater regulated by General Permit CAS000001 (Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities), is prohibited. 3.3. The overflow or bypass of wastewater from the Discharger’s collection, treatment, or disposal facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7 (Bypass), is prohibited. 3.4. Creation of a condition of pollution, contamination, or nuisance, as defined by section 13050 of the California Water Code, is prohibited. 3.5. The discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat. 3.6. The discharge of radioactive substances is prohibited. 3.7. The average dry weather daily discharge flow shall not exceed 5.4 million gallons per day (MGD). 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS 4.1. Effluent Limitations – Discharge Point 001 4.1.1. Final Effluent Limitations – Discharge Point 001 4.1.1.1. The Discharger shall maintain compliance with the following effluent limitations at Discharge Point 001, with compliance measured at Monitoring Location EFF- 001A or EFF-001B as described in the Monitoring and Reporting Program (MRP), Attachment E. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 8 Table 2. Effluent Limitations at Discharge Point 001 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1,351 2,252 - - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - - TSS lbs/day[1] 425 1,351 3,378 - - - - pH[2],[3] standard units - - - 7.0 8.3 - - Oil and Grease mg/L 5 - 10 - - - - Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - - Dissolved Oxygen mg/L - - - 4.0 - - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.01 2 - 0.024 - - - - Chlorodibromom ethane (Dibromochlorom ethane) µg/L 0.40 - 0.81 - - - - Chloroform µg/L 60 - 120.6 - - - - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 9 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Dichlorobromom ethane µg/L 0.56 - 0.96 - - - - Methylene Chloride µg/L 4.7 - 9.45 - - - - Pentachlorophen ol µg/L 0.28 - 0.56 - - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - - Nitrite, Total mg/L 1 - - - - - - Un-ionized Ammonia mg/L 0.02 5 - - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - - Molybdenum mg/L 0.01 - - - - - - Total Dissolved Solids mg/L - - - - - 650[10] Chloride mg/L - - - - - 100[10] Sodium mg/L - - - - - 50[10] Sulfate mg/L -- - - - - 100[10] Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail ” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 10 [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 7.0-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 7.0-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0 -9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 7.0-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 - day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in -stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP -Attachment E). [10] Based on a 12-month running mean. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 11 4.1.1.2. Percent Removal: The average monthly percent removal of BOD 5-day at 20°C and total suspended solids shall not be less than 85 percent. 4.1.1.3. Floating Material: Discharge of treated wastewater through Discharge Point 001 shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 4.1.2. Interim Effluent Limitations – Not Applicable 4.2. Land Discharge Specifications – Not Applicable 4.3. Recycling Specifications – Discharge Point 002 As specified below, this Order conditionally authorizes the Discharger to act as the producer of recycled (or reclaimed) water and to reuse recycled water onsite at the Facility and for other purposes. The Discharger is responsible for compliance with all applicable requirements associated with the production and onsite use of recycled water as specified within this Order. The Discharger filed a California Code of Regulations title 22 engineering report on August 14, 2020, that described recycled water quality produced at the Facility as "disinfected tertiary" (as defined in title 22, section 60301.230) and submitted a Notice of Intent (NOI) on August 14, 2020, to enroll under the State Water Board General Water Reclamation Requirements for Recycled Water Use (Order WQ 2016-0068-DDW). The distribution and offsite reuse of recycled water produced by the Facility are subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. Order WQ 2016-0068-DDW supersedes Waste Discharge/Master Reclamation Requirements Order R3-2003-081. 4.3.1. Reclamation and use of treated wastewater shall adhere to applicable requirements of California Water Code sections 13500-13577 (Water Reclamation) and California Code of Regulations, title 17 sections 7583-7586, title 17 sections 7601-7605, and title 22 sections 60301-60355 (Uniform Statewide Recycling Criteria). 4.3.2. Recycled water production shall comply with a title 22 engineering report approved by DDW that demonstrates or defines compliance with the Uniform Statewide Recycling Criteria. 4.3.3. Recycled water shall be disinfected tertiary recycled water, as defined by California Code of Regulations title 22, section 60301.230. 4.3.4. Recycled water shall be adequately filtered, and disinfected, as defined in title 22. 4.3.5. Turbidity in tertiary recycled water shall not exceed any of the following limits: 4.3.5.1. An average of 0.2 NTU within a 24-hour period; and 4.3.5.2. 0.5 NTU at any time. 4.3.6. Total coliform bacteria measured in the disinfected recycled water shall not exceed the following limits: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 12 4.3.6.1. An MPN of 2.2 per 100 mL calculated as a median concentration utilizing the bacteriological results of the last seven days for which analyses have been completed, 4.3.6.2. An MPN of 23 per 100 mL in more than one sample in any 30-day period, and 4.3.6.3. No sample shall exceed an MPN of 240 total coliform bacteria per 100 mL. 4.3.7. The Discharger shall discontinue delivery of recycled water to distributors and users during any period in which it has reason to believe that the limits established in this Order are not being met. The delivery of recycled water shall not be resumed until all conditions that caused the limits to be violated have been corrected. 4.3.8. Recycled water shall not exceed any maximum contaminant level established pursuant to sections 116275(c)(1) and (d) of the California Health and Safety Code or established by the U.S. EPA. 4.3.9. Recycled water disinfected with chlorine shall have a chlorine concentration time modal contact time (CT) value of not less than 450 mg-min/L at all times with a modal contact time of at least 90 minutes based on peak dry weather design flow. 4.3.10 If a disinfection method other than chlorine is used, the disinfection process shall be a process that, when combined with the filtration process, has been demonstrated to inactivate and/or remove 99.999 percent of the plaque forming units of F-specific bacteriophage MS2, or polio virus in the wastewater. A virus that is at least as resistant to disinfection as polio virus may be used for purposes of the demonstration. 4.3.11. The Discharger shall adhere to the manufacturer’s recommended operating conditions for the ultraviolet (UV) system. 4.3.12. Personnel involved in producing, transporting, or using recycled water shall be informed of possible health hazards that may result from contact and use of recycled water. 4.3.13. All areas where recycled water is in use and with public access shall be posted with signs in English and an international symbol to warn the public that recycled wastewater is being stored or used. 4.3.14. Recycled water systems at the Facility shall be properly labeled and regularly inspected to ensure proper operation, absence of leaks, and absence of illegal connections. 5. RECEIVING WATER LIMITATIONS 5.1. Surface Water Limitations Receiving water limitations are based on water quality objectives contained in the Water Quality Control Plan for the Central Coastal Basin (Basin Plan) and are a required part of this Order. The discharge shall not cause a violation of the following receiving water limitations in San Luis Obispo Creek. The discharge from the wastewater treatment facility shall comply with the following in the receiving waters: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 13 5.1.1. Waters shall be free of coloration that causes nuisance or adversely affects beneficial uses. Coloration attributable to materials of waste origin shall not be greater than 15 units or 10 percent above natural background color, whichever is greater. 5.1.2. Waters shall not contain taste or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, that cause nuisance, or that adversely affect beneficial uses. 5.1.3. Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.4. Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.5. Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. 5.1.6. Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. 5.1.7. Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses. 5.1.8. The suspended sediment load and suspended sediment discharge rate to surface waters shall not be altered in such a manner as to cause nuisance or adversely affect beneficial uses. 5.1.9 Concentrations of toxic metals and inorganic chemicals in waters shall not be increased in such a manner that may adversely affect beneficial uses. 5.1.10. Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Increase in turbidity attributable to controllable water quality factors shall not exceed the following limits. 5.1.10.1. Where natural turbidity is between 0 and 50 NTUs, increases shall not exceed 20 percent. 5.1.10.2. Where natural turbidity is between 50 and 100 NTUs, increases shall not exceed 10 NTU. 5.1.10.3. Where natural turbidity is greater than 100 NTUs, increases shall not exceed 10 percent. 5.1.11. The pH value shall not be depressed below 7.0 nor raised above 8.3. The change in normal ambient pH levels shall not exceed 0.5 units. 5.1.12. Dissolved oxygen concentrations in receiving waters shall not be reduced below 7.0 mg/L at any time. 5.1.13. Discharged effluent shall not cause the receiving water temperature to increase more than 5° Fahrenheit (F) above the receiving water temperature. If, due to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 14 the Creek’s low temperature as determined by early-morning monitoring, the discharge causes the Creek’s temperature to exceed the limit, the Discharger must ensure the discharge shall not cause the receiving water to exceed 72.5° F (22.5° C). The discharger shall monitor the Creek again four hours after discovering the exceedance and shall report both results to the Executive Officer in the monthly self-monitoring report. 5.1.14. All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge. 5.1.15. The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/L (as N) in the receiving water. 5.1.16. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect the beneficial uses of the receiving water. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life. For waters where existing concentrations are presently nondetectable or where beneficial uses would be impaired by concentrations in excess of nondetectable levels, total identifiable chlorinated hydrocarbon pesticides shall not be present at concentrations detectable within the accuracy of analytical methods as prescribed in Standard Methods for the Examination of Water and Wastewater, latest edition, or other equivalent methods approved by the Executive Officer. 5.1.17. Waters shall not contain organic substances in concentrations greater than those listed in the table below: Table 3. Organic Substances Water Quality Criteria Parameter Units Water Quality Objective Methylene Blue Activated Substances mg/L 0.2 Phenols ug/L 1.0 Polychlorinated Biphenyls (PCBs) [1] µg/L 0.3 Phthalate Esters µg/L 0.002 [1] PCBs refer to sum of PCB 1016, 1221, 1232, 1242, 1248, 1254, and 1260. 5.1.18. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstance shall receiving waters contain concentrations of radionuclides in excess of the maximum contaminant levels (MCLs) for radioactivity presented in title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.1.19. Receiving waters shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 15 Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.1.20. Receiving waters shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural beneficial use . Interpretation of adverse effects shall be derived from the University of California Agricultural Extension Service guidelines presented in section 3, Table 3-1 of the 2019 Basin Plan. 5.1.21. Receiving waters shall not contain concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in section 3, Table 3-2 of the Basin Plan. Salt concentrations for irrigations waters shall be controlled through implementation of the anti-degradation policy to the effect that mineral constituents of currently or potentially usable waters shall not be increased. 5.1.22. Receiving waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife in excess of the levels presented in section 3, Table 3-3 of the 2019 Basin Plan. The concentrations of metals listed in the table below shall not be exceeded for the protection of aquatic life. Table 4. Hardness Dependent Metals Criteria Parameter Units Receiving Water Hardness >100 mg/L calcium carbonate (CaCO3) Receiving Water Hardness <100 mg/L CaCO3 Cadmium mg/L 0.003 0.0004 Chromium mg/L 0.05 0.05 Copper mg/L 0.03 0.01 Lead mg/L 0.03 0.03 Mercury mg/L 0.0002 0.0002 Nickel mg/L 0.4 0.1 Zinc mg/L 0.2 0.004 5.1.23. E. coli concentrations shall not exceed 100 MPN/100 mL as a 6-week rolling geometric mean, calculated weekly. A statistical threshold value (STV) of 320 MPN/100 mL for E. coli shall not be exceeded by more than 10 percent of samples collected in a calendar month, calculated in a static manner. 5.1.24. Discharges shall not cause receiving water to exceed the water quality objectives for the Estero Bay Hydrologic Unit (San Luis Obispo Creek Sub-Area) specifically identified by Table 3-5 of the 2019 Basin Plan, as shown in the table below. Objectives shown are annual mean values. Objectives are based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 5. Annual Mean Surface Water Quality Objectives CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 16 Parameter Units Annual Mean Total Dissolved Solids mg/L 650 Chloride mg/L 100 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 5.2. Groundwater Limitations Activities at the Facility shall not cause exceedance/deviation from the following water quality objectives for groundwater established by the 2019 Basin Plan. The Central Coast Water Board may require the Discharger to investigate the cause of exceedances in the groundwater before determining whether the Discharger caused any water condition that exceeds the following groundwater limitations. 5.2.1. Groundwater shall not contain taste or odor-producing substances in concentrations that adversely affect beneficial uses. 5.2.2. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstances shall groundwater contain concentrations of radionuclides in excess of the MCLs for radioactivity presented in Title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.2.3. The Discharger shall not cause a statistically significant increase of mineral constituent concentrations in underlying groundwater as determined by comparison of samples collected from wells located up-gradient and down- gradient of the waters affected by the discharge. 5.2.4. The median concentration of coliform organisms in groundwater, over any seven - day period, shall be less than 2.2 organisms per 100 mL. 5.2.5. Groundwater shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431 -A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.2.6. Groundwater shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural supply beneficial use. Interpretation of adverse effects shall be as derived in University of California Agricultural Extension Service guidelines provided in Table 3-1 of the 2019 Basin Plan. 5.2.7. Groundwater used for irrigation and livestock watering shall not exceed concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in chapter 3, Table 3 -2 of the 2019 Basin Plan. 5.2.8. Groundwater shall not contain constituents greater than the following concentrations established in Table 3-6 of the 2019 Basin Plan for groundwaters within the San Luis Obispo Creek sub-area (Estero Bay sub-basin). Objectives CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 17 shown are annual median values. Objectives based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 6. Groundwater Objectives Parameter Units Annual Median TDS mg/L 900 Chloride mg/L 200 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 Nitrogen mg/L 5 6. PROVISIONS 6.1. Standard Provisions 6.1.1. The Discharger shall comply with all Standard Provisions included in Attachment D. 6.1.2. The Discharger shall comply with Central Coast Water Board Standard Provisions in Attachment D. In the event that there is any conflict, duplication, or overlap between provisions specified by this Order, the more stringent provision shall apply. 6.2. Monitoring and Reporting Program (MRP) Requirements The Discharger shall comply with the MRP, and future revisions thereto, in Attachment E. 6.3. Special Provisions 6.3.1. Reopener Provisions 6.3.1.1. This Order may be reopened for modification, or revocation and reissuance, as a result of the detection of a reportable priority pollutant generated by special conditions included in this Order. These special conditions may be, but are not limited to, fish tissue sampling, whole effluent toxicity, monitoring requirements on internal waste stream(s), monitoring for surrogate parameters, and other new information. Additional requirements may be included in this Order as a result of the special condition monitoring data. 6.3.1.2. This Order may be reopened and modified in accordance with NPDES regulations at 40 Code of Federal Regulations (CFR) parts 122 and 124, as necessary, to include additional conditions or limitations based on newly available information or to implement any U.S. EPA approved, new, state water quality objective. 6.3.1.3. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 18 to cause, or contributes to an excursion above a State Implementation Policy (SIP) water quality objective. 6.3.1.4. This Order may be reopened and modified to revise the most sensitive species to be used for acute and/or chronic aquatic toxicity testing once the required species sensitivity is completed in accordance with section 5 of the MRP (Attachment E). Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. 6.3.1.5 This Order may be reopened and modified to reevaluate reasonable potential for acute toxicity, and establish acute toxicity effluent limitations, if warranted, after the evaluation of new data and information. 6.3.2. Special Studies, Technical Papers and Additional Monitoring Requirements 6.3.2.1. Toxicity Reduction Requirements For compliance with the Basin Plan’s narrative toxicity objective, this Order requires the Discharger to conduct acute and chronic whole effluent toxicity (WET) testing, as specified in section 5 of the MRP. Furthermore, this Provision requires the Discharger to investigate the causes of and identify corrective actions to reduce or eliminate effluent toxicity. If the discharge exceeds the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring established in this Provision, the Discharger is required to initiate a Toxicity Reduction Evaluation (TRE) in accordance with an approved TRE Work Plan and take actions to mitigate the impact of the discharge and prevent recurrence of toxicity. A TRE is a site-specific study conducted in a stepwise process to identify the source(s) of toxicity and the effective control measures for effluent toxicity. TREs are designed to identify the causative agents and sources of whole effluent toxicity, evaluate the effectiveness of the toxicity control options, and confirm the reduction in effluent toxicity. This Provision includes requirements for the Discharger to update and submit their TRE Work Plan and includes procedures for accelerated toxicity monitoring and TRE initiation: 6.3.2.1.1. TRE Work Plan. Within 90 days of the effective date of this Order, the Discharger shall submit to the Central Coast Water Board an updated TRE Work Plan for approval by the Executive Officer. The TRE Work Plan shall outline the procedures for identifying the source(s) of and reducing or eliminating effluent toxicity. The TRE Work Plan must be developed in accordance with U.S. EPA guidance and be of adequate detail to allow the Discharger to immediately initiate a TRE as required in this Provision. 6.3.2.1.2. Accelerated Monitoring and TRE Initiation. When the numeric toxicity monitoring trigger or effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all test acceptability criteria (TAC), the Discharger shall initiate accelerated monitoring as required in the Accele rated Monitoring Specifications in section 5 of the MRP. The Discharger shall initiate a TRE to address effluent toxicity if any WET testing results exceed CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 19 the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring. 6.3.3. Best Management Practices and Pollution Prevention 6.3.3.1. Salt and Nutrient Management Program 6.3.3.1.1 The Discharger shall continue to update and implement an ongoing Salt Management Program, with the intent of reducing mass loading of salts in treated effluent and attainment of applicable water quality objectives for salts in the San Luis Obispo Creek Sub-Basin Area of the Estero Bay Drainage Basin. Additionally, the Discharger shall continue to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable water quality objectives for nutrients in the same basin. 6.3.3.1.2 Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. 6.3.3.1.3 Nutrient reduction measures shall focus on optimizing wastewater treatment processes for nitrification and denitrification, or other means of nitrogen removal. Reduction measures may also include source control (non-human waste from commercial and industrial sources) as appropriate. 6.3.3.1.4 As part of the Salt and Nutrient Management Program, the Discharger shall submit an annual report describing salt and nutrient reduction efforts as described in the section 9.3 of the MRP (Attachment E). 6.3.3.1.5 As an alternative to the Salt and Nutrient Management Program requirements described above, upon Executive Officer approval, the Discharger may submit documentation and summary of participation in a regional salt/nutrient management plan implemented under the provisions of State Water Board Resolution No. 2018-0057 (Recycled Water Policy). 6.3.3.2. Pollutant Minimization Program 6.3.3.2.1.The Discharger shall develop and conduct a Pollutant Minimization Program (PMP) as further described below when there is evidence (e.g., sample results reported as detected not quantifiable (DNQ) when the effluent limitation is less than the MDL, sample results from analytical methods more sensitive than those methods required by this Order, presence of whole effluent toxicity, health advisories for fish consumption, results of benthic or aquatic organism tissue sampling) that a priority pollutant is present in the effluent above an effluent limitation and either: 6.3.3.2.1.1. A sample result is reported as DNQ and the effluent limitation is less than the reporting limit (RL); or 6.3.3.2.1.2. A sample result is reported as non-detect (ND) and the effluent limitation is less than the MDL, using definitions described in Attachment A and reporting protocols described in MRP section 10.2.4. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 20 6.3.3.2.2. The PMP shall include, but not be limited to, the following actions and submittals acceptable to the Central Coast Water Board Executive Officer: 6.3.3.2.2.1. An annual review and semi-annual monitoring of potential sources of the reportable priority pollutant(s), which may include fish tissue monitoring and other bio-uptake sampling; 6.3.3.2.2.2. Quarterly monitoring for the reportable priority pollutant(s) in the influent to the wastewater treatment system; 6.3.3.2.2.3. Submittal of a control strategy designed to proceed toward the goal of maintaining concentrations of the reportable priority pollutant(s) in the effluent at or below the effluent limitation; 6.3.3.2.2.4. Implementation of appropriate cost-effective control measures for the reportable priority pollutant(s), consistent with the control strategy; and 6.3.3.1.2.5. An annual status report that shall be sent to the Central Coast Water Board including: 6.3.3.1.2.5.1. All PMP monitoring results for the previous year; 6.3.3.1.2.5.2. A list of potential sources of the reportable priority pollutant(s); 6.3.3.1.2.5.3. A summary of all actions undertaken pursuant to the control strategy; and 6.3.3.1.2.5.4. A description of actions to be taken in the following year. 6.3.4. Construction, Operation and Maintenance Specifications 6.3.4.1. The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.3.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.3.5.1. Biosolids. The handling, management, and disposal of sludge and solids derived from wastewater treatment must comply with applicable provisions of U.S. EPA regulations at 40 CFR sections 257, 258, 501, and 503, including all monitoring, record keeping, and reporting requirements. Solids and sludge treatment, storage, and disposal or reuse shall not create a nuisance, such as objectionable odors or flies, and shall not result in ground water contamination. Sites for solids and sludge treatment and storage shall have adequate facilities to divert surface water runoff from adjacent areas to protect the boundaries of such sites from erosion, and to prevent drainage from treatment and storage sites. The treatment, storage, disposal, or reuse of sewage sludge and solids shall not cause waste material to be in a position where it is, or can be, conveyed from the treatment and storage sites and deposited into waters of the State. The Discharger is responsible for assuring that all biosolids produced at its facility are used or disposed of in accordance with the above rules, regardless of whether the Discharger uses or disposes of the biosolids itself, or transfers them to another party for further treatment, use, or disposal. The Discharger is CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 21 responsible for informing subsequent preparers, appliers, and disposers of the requirements that they must adhere to these rules. 6.3.5.2. Pretreatment. The Discharger shall be responsible for the performance for all pretreatment requirements contained in 40 CFR part 403 and shall be subject to enforcement actions, penalties, fines, and other remedies by the U.S. EPA, or other appropriate parties, as provided in the CWA, as amended (33 USC 1351 et seq.). The Discharger shall implement and enforce its approved POTW Pretreatment Program. The Discharger’s approved POTW Pretreatment Program is hereby made an enforceable condition of this permit. U.S. EPA or the Central Coast Water Board may initiate enforcement action against an industrial user for noncompliance with applicable standards and requirements as provided in the CWA. The Discharger shall enforce the requirements promulgated under sections 307 (b), 307 (c), 307 (d), and 402 (b) of the CWA. The Discharger shall cause industrial users subject to Federal Categorical Standards to achieve compliance no later than the date specified in those requirements or, in the case of a new industrial user, upon commencement of the discharge. The Discharger shall perform the pretreatment functions as required in 40 CFR part 403, including, but not limited to the following: 6.3.5.2.1. Implement the necessary authorities as provided in 40 CFR section 403.8 (f) (1); 6.3.5.2.2. Enforce the pretreatment requirements under 40 CFR sections 403.5 and 403.6; 6.3.5.2.3. Implement the programmatic functions as provided in 40 CFR section 403.8 (f) (2); and 6.3.5.2.4. Provide the requisite funding and personnel to implement the pretreatment program as provided in 40 CFR section 403.8 (f) (3). 6.3.5.5. Resource Recovery from Anaerobically Digestible Material. If the Discharger will receive hauled-in anaerobically digestible material for injection into an anaerobic digester, the Discharger shall notify the Central Coast Water Board and develop and implement standard operating procedures for this activity. The standard operating procedures shall be developed prior to receiving hauled-in anaerobically digestible material. The standard operating procedures shall address material handling, including unloading, screening, or other processing prior to anaerobic digestion; transportation; spill prevention; and spill response. In addition, the standard operating procedures shall address avoidance of the introduction of materials that could cause interference, pass- through, or upset of the treatment processes; avoidance of prohibited material; vector control; odor control; operation and maintenance; and the disposit ion of any solid waste segregated from introduction to the digester. The Discharger shall train its staff on the standard operating procedures and shall maintain records for a minimum of five years for each load received, describing the hauler, waste type, and quantity received. In addition, the Discharger shall CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 22 maintain records for a minimum of five years for the disposition, location, and quantity of cumulative pre-digestion-segregated solid waste hauled offsite. 6.3.6. Other Special Provisions 6.3.6.1. Salt Management. Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. The Discharger shall assess additional pretreatment measures that may be taken to reduce influent salt concentrations and include a discussion of proposed and implemented measures in the annual report described below. The Discharger must also implement outreach to residential, commercial, and industrial salt contributors with the goal of reducing salts discharged to the collection system. 6.3.6.2. Discharges of Stormwater. For the control of stormwater discharged from the site of the wastewater treatment and disposal facilities, if applicable, the Discharger shall seek authorization to discharge under and meet the requirements of the State Water Board’s Water Quality Order 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.3.6.3. Statewide General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order No. 2022-0103-DWQ) The Discharger is subject to the requirements of and must separately comply with State Water Board Order 2022-0103-DWQ, Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems, including monitoring and reporting requirements, and any subsequent revision to that order. This General Permit, adopted on December 6, 2022, is applicable to all “federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California.” The purpose of the General Permit is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled under the General Permit. 6.3.6.4. Climate Change Adaptation Implementation Progress Report. On May 1, 2029, the Discharger shall submit a Climate Change Adaptation Implementation Progress Report2 to the Central Coast Water Board Executive Officer describing the Discharger’s progress in implementing, monitoring, and updating its long-term approach for identifying and addressing climate change hazards and vulnerabilities at the Facility, including all associated infrastructure (e.g., treatment facilities, conveyances to discharge points, discharge facilities). 2 In place of a static document, the Discharger may develop a living document and/or set of tools that fulfills the components outlined for the Climate Change Adaptation Program. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 23 The Climate Change Adaptation Implementation Report shall, at a minimum, include the following components: 6.3.6.4.1. Climate Change Adaptation Implementation Status – Provide a status update on any city or county-wide reports that address Facility and or collection system climate change adaptation planning and or implantation. Submit copies of document(s) to CIWQS as attachments. 6.3.6.4.2. Resiliency Actions – Report progress on actions that build facility and operational resilience to identified vulnerabilities, accounting for options that minimize resource impacts. For the anticipated life of the facility, include an analysis of: • Precipitation pattern changes o Drought – Decreased influent quantity and quality o Peak Events – Flooding and increased influent quantity • Temperature fluctuations and extremes • Increased wildfires • Energy resilience o Energy efficiency o Renewable energy generation o Increased power outages • Biosolid reuse • Water recycling 6.3.6.4.3. Adaptation Strategy – Report progress and adjustments made to strategy to complete Resiliency Actions, encompassing the following: 6.3.6.4.3.1. Prioritization – How resiliency actions were prioritized based on risks to water quality, but also accounting for costs and benefits. 6.3.6.4.3.2. Schedule and Milestones – Ongoing and changing timeframes to complete prioritized resiliency actions and/or climate change hazard triggers to inform when the Discharger shall implement actions. Milestones to complete critical steps for prioritized Resiliency Actions, designed to demonstrate measurable progress at a steady, or accelerated, completion pace over the established timeframes. 6.3.6.4.3.3. Financial Planning – Costs of reported implementation and monitoring measures, projected costs necessary to continue implementation and monitoring of resiliency actions, and strategy to procure funds. 6.3.7. Compliance Schedules – Not Applicable 7. COMPLIANCE DETERMINATION 7.1. General Compliance with effluent limitations for reportable pollutants shall be determined using sample reporting protocols defined in the MRP and Attachment A of this Order. For purposes of reporting and administrative enforcement by the Central Coast and State Water Boards, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the reportable pollutant in the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 24 monitoring sample is greater than the effluent limitation and greater than or equal to the reported Minimum Level (ML). 7.2. Chronic Toxicity The discharge is subject to determination of “Pass” or “Fail” from a chronic toxicity test using the Test of Significant Toxicity (TST) statistical t-test approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. The null hypothesis (Ho) for the TST statistical approach is: Mean discharge “in-stream” waste concentration (IWC) response ≤0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub -lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge (100 percent effluent) and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be reported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). 7.3. Multiple Sample Data When determining compliance with a measure of central tendency (arithmetic mean, geometric mean, median, etc.) of multiple samples analyses and the data set contains one or more reported determinations of DNQ, or ND, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 7.3.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 7.3.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 25 even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 7.4. Average Monthly Effluent Limitation (AMEL) If the average of daily discharges over a calendar month exceeds the AMEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that month for that parameter (e.g., resulting in 31 days of non-compliance in a 31-day month). The average of daily discharges over the calendar month that exceeds the AMEL for a parameter will be considered out of compliance for that month only. If only a single sample is taken during the calendar month and the analytical result for that sample exceeds the AMEL, the Discharger will be considered out of compliance for that calendar month. For any one calendar month during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar month. 7.5. Average Weekly Effluent Limitation (AWEL) If the average of daily discharges over a calendar week exceeds the AWEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that week for that parameter, resulting in seven days of non-compliance. The average of daily discharges over the calendar week that exceeds the AWEL for a parameter will be considered out of compliance for that week only. If only a single sample is taken during the calendar week and the analytical result for that sample exceeds the AWEL, the Discharger will be considered out of compliance for that calendar week. For any one calendar week during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar week. 7.6. Maximum Daily Effluent Limitation (MDEL) If a daily discharge exceeds the MDEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for that parameter for that one day only within the reporting period. For any one day during which no sample is taken, no compliance determination can be made for that day. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-1 A. ATTACHMENT A – DEFINITIONS Arithmetic Mean (μ) Also called the average, is the sum of measured values divided by the number of samples. For ambient water concentrations, the arithmetic mean is calculated as follows: where: Σx is the sum of the measured ambient water concentrations, and n is the number of samples. Average Monthly Effluent Limitation (AMEL) The highest allowable average of daily discharges over a calendar month, calculated as the sum of all daily discharges measured during a calendar month divided by the number of daily discharges measured during that month. Average Weekly Effluent Limitation (AWEL) The highest allowable average of daily discharges over a calendar week (Sunday through Saturday), calculated as the sum of all daily discharges measured during a calendar week divided by the number of daily discharges measured during that week. Bioaccumulative Those substances taken up by an organism from its surrounding medium through gill membranes, epithelial tissue, or from food and subsequently concentrated and retained in the body of the organism. Bioassay A test used to evaluate the relative potency of a chemical or a mixture of chemicals by comparing its effect on a living organism with the effect of a standard preparation on the same type of organism. Calendar Month(s) A period of time from a day of one month to the day before the corresponding day of the next month if the corresponding day exists, or if not to the last day of the next month (e.g., from January 1 to January 31, from June 15 to July 14, or from January 31 to February 28). Calendar Quarter A period of time defined as three consecutive calendar months. Calendar Year A period of time defined as twelve consecutive calendar months. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-2 Carcinogenic Pollutants are substances that are known to cause cancer in living organisms. Chronic Aquatic Toxicity Test A test to determine an adverse effect (sublethal or lethal) on a group of aquatic test organisms during an exposure of duration long enough to assess sub -lethal effects. Compliance with the effluent limitation for chronic toxicity in this Order is demonstr ated by conducting chronic toxicity tests for the effluent as described in section 7.15 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E), and in accordance with the TST statistical approach. Coefficient of Variation (CV) CV is a measure of the data variability and is calculated as the estimated standard deviation divided by the arithmetic mean of the observed values. Continuous Dischargers Facilities that discharge without interruption throughout its operating hours, except for infrequent shutdowns for maintenance, process changes, or other similar activities, and that discharge throughout the calendar year. Daily Discharge Daily Discharge is defined as either: (1) the total mass of the constituent discharged over the calendar day (12:00 am through 11:59 pm) or any 24 -hour period that reasonably represents a calendar day for purposes of sampling (as specified in the permit), for a constituent with limitations expressed in units of mass or; (2) the unweighted arithmetic mean measurement of the constituent over the day for a constituent with limitations expressed in other units of measurement (e.g., concentration). The daily discharge may be determined by the analytical results of a composite sample taken over the course of one day (a calendar day or other 24-hour period defined as a day) or by the arithmetic mean of analytical results from one or more grab samples taken over the course of the day. For composite sampling, if one day is defined as a 24-hour period other than a calendar day, the analytical result for the 24-hour period will be considered as the result for the calendar day in which the 24-hour period ends. Detected, but Not Quantified (DNQ) DNQ are those sample results less than the reporting limit (RL), but greater than or equal to the laboratory’s MDL. Sample results reported as DNQ are estimated concentrations. Dilution Credit Dilution Credit is the amount of dilution granted to a discharge in the calculation of a water quality-based effluent limitation, based on the allowance of a specified mixing zone. It is calculated from the dilution ratio or determined through conducting a mixing zone study or modeling of the discharge and receiving water. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-3 Dilution Ratio The critical low flow of the upstream receiving water divided by the flow of the effluent discharged. Effluent Concentration Allowance (ECA) ECA is a value derived from the water quality criterion/objective, dilution credit, and ambient background concentration that is used, in conjunction with the coefficient of variation for the effluent monitoring data, to calculate a long -term average (LTA) discharge concentration. The ECA has the same meaning as wasteload allocation (WLA) as used in United States Environmental Protection Agency (U.S. EPA) guidance (Technical Support Document for Water Quality-based Toxics Control, March 1991, second printing, EPA/505/2-90-001). Enclosed Bays Enclosed Bays means indentations along the coast that enclose an area of oceanic water within distinct headlands or harbor works. Enclosed bays include all bays where the narrowest distance between the headlands or outermost harbor works is less than 75 percent of the greatest dimension of the enclosed portion of the bay. Enclosed bays include, but are not limited to, Humboldt Bay, Bodega Harbor, Tomales Bay, Drake’s Estero, San Francisco Bay, Morro Bay, Los Angeles-Long Beach Harbor, Upper and Lower Newport Bay, Mission Bay, and San Diego Bay. Enclosed bays do not include inland surface waters or ocean waters. Estimated Chemical Concentration The estimated chemical concentration that results from the confirmed detection of the substance by the analytical method below the minimum level (ML) value. Estuaries and Coastal Lagoons Estuaries means waters, including coastal lagoons, located at the mouths of streams that serve as areas of mixing for fresh and ocean waters. Coastal lagoons and mouths of streams that are temporarily separated from the ocean by sandbars shall be considered estuaries. Estuarine waters shall be considered to extend from a bay or the open ocean to a point upstream where there is no significant mixing of fresh water and seawater. Estuarine waters included, but are not limited to, the Sacramento-San Joaquin Delta, as defined in California Water Code section 12220, Suisun Bay, Carquinez Strait downstream to the Carquinez Bridge, and appropriate areas of the Smith, Mad, Eel, Noyo, Russian, Klamath, San Diego, and Otay rivers. Estuaries do not include inland surface waters or ocean waters. Flow-Through Acute Toxicity Testing Systems A toxicity testing system where an effluent sample is either pumped continuously from the sampling point directly to a dilutor system, or collected and placed in a tank adjacent to the test laboratory and pumped continuously from the tank to a dilutor syst em. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-4 Inland Surface Waters All surface waters of the state that do not include the ocean, enclosed bays, or estuaries. Insignificant Dischargers National Pollutant Discharge Elimination System (NPDES) discharges that are determined to be a very low threat to water quality by the permitting authority. Instantaneous Maximum Effluent Limitation The highest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous maximum limitation). Instantaneous Minimum Effluent Limitation The lowest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous minimum limitation). In-stream Waste Concentration (IWC) The concentration of effluent in the receiving water after mixing as determined by the permitting authority. For purposes of aquatic toxicity testing for non-stormwater NPDES dischargers, the IWC shall be as described in section III.C.1 of the Toxicity Provisions. For assessing whether receiving waters meet the numeric water quality objectives (WQOs), the undiluted ambient water shall be used as the IWC in the TST as indicated in section III.B.3 of the Toxicity Provisions. Maximum Daily Effluent Limitation (MDEL) The highest allowable daily discharge of a pollutant, over a calendar day (or 24 -hour period). For pollutants with limitations expressed in units of mass, the daily discharge is calculated as the total mass of the pollutant discharged over the day. For pollutants with limitations expressed in other units of measurement, the daily discharge is calculated as the arithmetic mean measurement of the pollutant over the day. For the purposes of chronic and acute aquatic toxicity, an MDEL is an effluent limitation based on the outcome of the TST approach and the resulting percent effect at the IWC, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Maximum Daily Effluent Target (MDET) For the purposes of chronic and acute aquatic toxicity, an MDET is a target used to determine whether a Toxicity Reduction Evaluation (TRE) should be conducted. Not meeting the MDET is not a violation of an effluent limitation. Median The middle measurement in a set of data. The median of a set of data is found by first arranging the measurements in order of magnitude (either increasing or decreasing order) If the number of measurements (n) is odd, then: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-5 If n is even, then: (i.e., the midpoint between the (n/2 and ((n/2)+1))). Median Monthly Effluent Limitation (MMEL) For the purposes of chronic and acute aquatic toxicity, an MMEL is an effluent limitation based on a maximum of three independent toxicity tests, analyzed using the TST, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Median Monthly Effluent Target (MMET) For the purposes of chronic and acute aquatic toxicity, an MMET is a target based on a maximum of three independent toxicity tests used to determine whether a TRE should be conducted. Not meeting the MMET is not a violation of an effluent limitation. Method Detection Limit (MDL) MDL is the minimum concentration of a substance that can be reported with 99 percent confidence that the measured concentration is distinguishable from method blank results, as defined in 40 Code of Federal Regulations (CFR) part 136, Attachment B. Minimum Level (ML) ML is the concentration at which the entire analytical system must give a recognizable signal and acceptable calibration point. The ML is the concentration in a sample that is equivalent to the concentration of the lowest calibration standard analyzed by a specific analytical procedure, assuming that all the method specified sample weights, volumes, and processing steps have been followed. Mixing Zone Mixing Zone is a limited volume of receiving water that is allocated for mixing with a wastewater discharge where water quality criteria can be exceeded without causing adverse effects to the overall water body. MMEL Compliance Tests For the purposes of chronic and acute aquatic toxicity, MMEL compliance tests are a maximum of two tests that are used in addition to the routine monitoring test to determine compliance with the chronic and acute aquatic toxicity MMEL and MDEL. MMET Tests For the purposes of chronic and acute aquatic toxicity, for dischargers not required to comply with numeric chronic toxicity effluent limitations, MMET tests are a maximum of two tests that are used in addition to the routine monitoring test to determine w hether a TRE should be conducted. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-6 Most Sensitive Species The single species selected from an array of test species to be used in a single species laboratory test series to determine toxic effects of effluent or ambient water. Non-Continuous Dischargers Dischargers that do not discharge in a continuous manner or do not discharge throughout the calendar year (e.g., intermittent and seasonal dischargers). Non-NPDES Dischargers Dischargers of waste that could affect the quality of waters of the State that are not regulated by the NPDES program. Non-Stormwater NPDES Dischargers Dischargers that are regulated pursuant to one or more NPDES permit(s), but excluding any discharges subject to the United States Code title 33 section 1342(p). This includes dischargers that discharge a combination of treated municipal or industrial wastewater and stormwater. Nonpoint Source A source that does not meet the definition of a point source, as defined below. Not Detected (ND) Sample results which are less than the laboratory’s MDL. Null Hypothesis A statement used in statistical testing that has been put forward either because it is believed to be true or because it is to be used as a basis for argument, but has not been proved. Ocean Waters The territorial marine waters of the State, as defined by California law, to the extent these waters are outside of enclosed bays, estuaries, and coastal lagoons. Discharges to ocean waters are regulated in accordance with the State Water Board’s Californi a Ocean Plan. Percent Effect The value that denotes the difference in response between the test concentration and the control, divided by the mean control response, and multiplied by 100. Permitting Authority The State Water Board or a regional water board that issues a permit, waste discharge requirements, water quality certification, or other authorization for the discharge or proposed discharge of waste. To the extent that the action is delegable, the term “Permitting Authority” can include the Executive Officer or Executive Director. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-7 Persistent Pollutants Persistent pollutants are substances for which degradation or decomposition in the environment is nonexistent or very slow. Point Source Any discernible, confined and discrete conveyance including, but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from whic h pollutants are or may be discharged. This term does not include agricultural stormwater discharges and return flows from irrigated agriculture. Pollutant Defined in section 502(6) of the CWA as “dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt and industrial, municipal, and agricultural waste discharged into water.” Pollutant Minimization Program (PMP) PMP means waste minimization and pollution prevention actions that include, but are not limited to, product substitution, waste stream recycling, alternative waste management methods, and education of the public and businesses. The goal of the PMP shall be to reduce all potential sources of a priority pollutant(s) through pollutant minimization (control) strategies, including pollution prevention measures as appropriate, to maintain the effluent concentration at or below the water quality-based effluent limitation. Pollution prevention measures may be particularly appropriate for persistent bioaccumulative priority pollutants where there is evidence that beneficial uses are being impacted. The Central Coast Water Board may consider cost effectiveness when establishing the requirements of a PMP. The completion and implementation of a Pollution Prevention Plan, if required pursuant to California Water Code section 13263.3(d), shall be considered to fulfill the PMP requirements. Pollution Prevention Pollution Prevention means any action that causes a net reduction in the use or generation of a hazardous substance or other pollutant that is discharged into water and includes, but is not limited to, input change, operational improvement, production process change, and product reformulation (as defined in California Water Code section 13263.3). Pollution prevention does not include actions that merely shift a pollutant in wastewater from one environmental medium to another environmental medium, unless clear environmental benefits of such an approach are identified to the satisfaction of the State Water Resources Control Board (State Water Board) or California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board). Publicly Owned Treatment Works (POTW) Facilities owned by a state or municipality that store, treat, recycle, and reclaim municipal sewage or industrial wastes of a liquid nature. Similar facilities that are privately, instead of publicly owned, are included in this definition for purposes of section III of the Toxicity Provisions. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-8 Reasonable Potential A designation used for a waste discharge that is projected or calculated to cause or contribute to an instream excursion above a water quality standard. Regulatory Management Decision (RMD) The decision that represents the maximum allowable error rates and thresholds for toxicity and non-toxicity that would result in an acceptable risk to aquatic life. Replicates Two or more independent organism exposures of the same treatment (i.e., effluent concentration) within a toxicity test. Replicates are typically conducted with separate test chambers and test organisms, each having the same effluent concentration. Reporting Level (RL) The RL is the ML (and its associated analytical method) chosen by the Discharger for reporting and compliance determination from the MLs included in this Order, including an additional factor if applicable as discussed herein. The MLs included in this Orde r correspond to approved analytical methods for reporting a sample result that are selected by the Central Coast Water Board either from Appendix 4 of the State Implementation Policy (SIP) in accordance with section 2.4.2 of the SIP or established in accordance with section 2.4.3 of the SIP. The ML is based on the proper application of method-based analytical procedures for sample preparation and the absence of any matrix interferences. Other factors may be applied to the ML depending o n the specific sample preparation steps employed. For example, the treatment typically applied in cases where there are matrix-effects is to dilute the sample or sample aliquot by a factor of ten. In such cases, this additional factor must be applied to th e ML in the computation of the RL. Response A measured biological effect (e.g., survival, reproduction, growth) as a result of exposure to a stimulus. Routine Monitoring Required monitoring that occurs during a permit term. Source of Drinking Water Any water designated as municipal or domestic supply (MUN) in a Central Coast Water Board Water Quality Control Plan for the Central Coastal Basin (Basin Plan). Species Sensitivity Screening An analysis to determine the single most sensitive species from an array of test species to be used in a single species laboratory test series. Standard Deviation (σ) Standard Deviation is a measure of variability that is calculated as follows: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-9 where: x is the observed value; µ is the arithmetic mean of the observed values; and n is the number of samples. Stormwater As defined at 40 C.F.R. section 122.26(b)(13) (Nov. 16, 1990) which states, ‘Storm water means storm water runoff, snow melt runoff, and surface runoff and drainage.” Test of Significant Toxicity (TST) A statistical approach used to analyze aquatic toxicity test data, as described in section IV.B.1.c of the Toxicity Provisions. Toxicity Identification Evaluation (TIE) Techniques used to identity the unexplained cause(s) of toxic event. A TIE involves selectively removing classes of chemicals through a series of sample manipulations, effectively reducing complex mixtures of chemicals in natural waters to simple components for analysis. Following each manipulation, the toxicity sample is assessed to see whether the toxicant class removed was responsible for the toxicity. Toxicity Reduction Evaluation (TRE) TRE is a study conducted in a step-wise process designed to identify the causative agents of effluent or ambient toxicity, isolate the sources of toxicity, evaluate the effectiveness of toxicity control options, and then confirm the reduction in toxicity. The first steps of the TRE consist of the collection of data relevant to the toxicity, including additional toxicity testing, and an evaluation of facility operations and maintenance practices, and best management practices. A Toxicity Identification Evaluation (TIE) may be required as part of the TRE, if appropriate. (A TIE is a set of procedures to identify the specific chemical(s) responsible for toxicity. These procedures are performed in three phases (characterization, identification, and confirmation) using aquatic organism toxicity tests.) Toxicity Provisions Refers to State Policy for Water Quality Control: Toxicity Provisions (adopted in 2020 and revised in 2021) of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California . CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT B-MAP B-1 B. ATTACHMENT B – MAP CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-1 C. ATTACHMENT C – FLOW SCHEMATIC CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-2 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-1 D. ATTACHMENT D – STANDARD PROVISIONS 1. STANDARD PROVISIONS – PERMIT COMPLIANCE 1.1. Duty to Comply 1.1.1. The Discharger must comply with all terms, requirements, and conditions of this Order. Any noncompliance constitutes a violation of the Clean Water Act (CWA) and the California Water Code (Water Code) and is grounds for enforcement action; permit termination, revocation and reissuance, or modification; denial of a permit renewal application; or a combination thereof. (40 Code of Federal Regulations (C.F.R.) 122.41(a); Water Code sections 13261, 13263, 13265, 13268, 13000, 13001, 13304, 13350, 13385.) 1.1.2. The Discharger shall comply with effluent standards or prohibitions established under Section 307(a) of the CWA for toxic pollutants within the time provided in the regulations that establish these standards or prohibitions, even if this Order has not yet been modified to incorporate the requirement. (40 C.F.R. 122.41(a)(1).) 1.2. Need to Halt or Reduce Activity Not a Defense It shall not be a defense for a Discharger in an enforcement action that it would have been necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this Order. (40 C.F.R. 122.41(c).) 1.3. Duty to Mitigate The Discharger shall take all reasonable steps to minimize or prevent any discharge in violation of this Order that has a reasonable likelihood of adversely affecting human health or the environment. (40 C.F.R. 122.41(d).) 1.4. Proper Operation and Maintenance The Discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the Discharger to achieve compliance with the conditions of this Order. Proper operation and maintenance also include adequate laboratory controls and appropriate quality assurance procedures. This provision requires the operation of backup or auxiliary facilities or similar systems that are installed by a Discharger only when necessary to achieve compliance with the conditions of this Order. (40 C.F.R. 122.41(e).) 1.5. Property Rights 1.5.1. This Order does not convey any property rights of any sort or any exclusive privileges. (40 C.F.R. 122.41(g).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-2 1.5.2. The issuance of this Order does not authorize any injury to persons or property or invasion of other private rights, or any infringement of state or local law or regulations. (40 C.F.R. 122.5(c).) 1.6. Inspection and Entry The Discharger shall allow the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board), State Water Resources Control Board (State Water Board), United States Environmental Protection Agency (U.S. EPA), and/or their authorized representatives (including an authorized contractor acting as their representative), upon the presentation of credentials and other documents, as may be required by law, to (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i); Water Code sections 13267, 13383): 1.6.1. Enter upon the Discharger's premises where a regulated facility or activity is located or conducted, or where records are kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(i); 40 C.F.R. 122.41(i)(1); Water Code sections 13267, 13383); 1.6.2. Have access to and copy, at reasonable times, any records that must be kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(2); Water Code sections 13267, 13383); 1.6.3. Inspect and photograph, at reasonable times, any facilities, equipment (including monitoring and control equipment), practices, or operations regulated or required under this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(3); Water Code sections 13267, 13383); and 1.6.4. Sample or monitor, at reasonable times, for the purposes of assuring Order compliance or as otherwise authorized by the CWA or the Water Code, any substances or parameters at any location. (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i)(4); Water Code sections 13267, 13383.) 1.7. Bypass 1.7.1. Definitions 1.7.1.1. “Bypass” means the intentional diversion of waste streams from any portion of a treatment facility. (40 C.F.R. 122.41(m)(1)(i).) 1.7.1.2. “Severe property damage” means substantial physical damage to property, damage to the treatment facilities, which causes them to become inoperable, or substantial and permanent loss of natural resources that can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production. (40 C.F.R. 122.41(m)(1)(ii).) 1.7.2. Bypass not exceeding limitations. The Discharger may allow any bypass to occur which does not cause exceedances of effluent limitations, but only if it is for essential maintenance to assure efficient operation. These bypasses are not subject to the provisions listed in Standard Provisions – Permit Compliance 1.7.3, 1.7.4, and 1.7.5 below. (40 C.F.R. 122.41(m)(2).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-3 1.7.3. Prohibition of bypass. Bypass is prohibited, and the Central Coast Water Board may take enforcement action against a Discharger for bypass, unless (40 C.F.R. 122.41(m)(4)(i)): 1.7.3.1. Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage (40 C.F.R. 122.41(m)(4)(i)(A)); 1.7.3.2. There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass that occurred during normal periods of equipment downtime or preventive maintenance (40 C.F.R. 122.41(m)(4)(i)(B)); and 1.7.3.3. The Discharger submitted notice to the Central Coast Water Board as required under Standard Provisions – Permit Compliance 1.7.5 below. (40 C.F.R. 122.41(m)(4)(i)(C).) 1.7.4. The Central Coast Water Board may approve an anticipated bypass, after considering its adverse effects, if the Central Coast Water Board determines that it will meet the three conditions listed in Standard Provisions – Permit Compliance 1.7.3 above. (40 C.F.R. 122.41(m)(4)(ii).) 1.7.5. Notice 1.7.5.1. Anticipated bypass. If the Discharger knows in advance of the need for a bypass, it shall submit prior notice, if possible, at least 10 days before the date of the bypass. The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part127. (40 C.F.R. 122.41(m)(3)(i).) 1.7.5.2. Unanticipated bypass. The Discharger shall submit a notice of an unanticipated bypass as required in Standard Provisions - Reporting 5.5 below (24-hour notice). The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(m)(3)(ii).) 1.8. Upset Upset means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the Discharger. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. (40 C.F.R. 122.41(n)(1).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-4 1.8.1. Effect of an upset. An upset constitutes an affirmative defense to an action brought for noncompliance with such technology-based permit effluent limitations if the requirements of Standard Provisions – Permit Compliance 1.8.2 below are met. No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review. (40 C.F.R. 122.41(n)(2).) 1.8.2 Conditions necessary for a demonstration of upset. A Discharger who wishes to establish the affirmative defense of upset shall demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that (40 C.F.R. 122.41(n)(3)): 1.8.2.1. An upset occurred and that the Discharger can identify the cause(s) of the upset (40 C.F.R. 122.41(n)(3)(i)); 1.8.2.2. The permitted facility was, at the time, being properly operated (40 C.F.R. 122.41(n)(3)(ii)); 1.8.2.3. The Discharger submitted notice of the upset as required in Standard Provisions – Reporting 5.5.2.2 below (24-hour notice) (40 C.F.R. 122.41(n)(3)(iii)); and 1.8.2.4. The Discharger complied with any remedial measures required under Standard Provisions – Permit Compliance 1.3 above. (40 C.F.R. 122.41(n)(3)(iv).) 1.8.3. Burden of proof. In any enforcement proceeding, the Discharger seeking to establish the occurrence of an upset has the burden of proof. (40 C.F.R. 122.41(n)(4).) 2. STANDARD PROVISIONS – PERMIT ACTION 2.1. General This Order may be modified, revoked and reissued, or terminated for cause. The filing of a request by the Discharger for modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not stay any Order condition. (40 C.F.R. 122.41(f).) 2.2. Duty to Reapply If the Discharger wishes to continue an activity regulated by this Order after the expiration date of this Order, the Discharger must apply for and obtain a new permit. (40 C.F.R. 122.41(b).) 2.3. Transfers This Order is not transferable to any person except after notice to the Central Coast Water Board. The Central Coast Water Board may require modification or revocation and reissuance of the Order to change the name of the Discharger and incorporate such other requirements as may be necessary under the CWA and the Water Code. (40 C.F.R. 122.41(l)(3), 122.61.) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-5 3. STANDARD PROVISIONS – MONITORING 3.1. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. (40 C.F.R. 122.41(j)(1).) 3.2. Monitoring must be conducted according to test procedures approved under 40 C.F.R. part 136 for the analyses of pollutants unless another method is required under 40 C.F.R. chapter 1, subchapter N. Monitoring must be conducted according to sufficiently sensitive test methods approved under 40 C.F.R. part 136 for the analysis of pollutants or pollutant parameters or as required under 40 C.F.R. chapter 1, subchapter N. For the purposes of this paragraph, a method is sufficiently sensitive when: 3.2.1. The method minimum level (ML) is at or below the level of the most stringent effluent limitation established in the permit for the measured pollutant or pollutant parameter, and either the method ML is at or below the level of the most stringent applicable water quality criterion for the measured pollutant or pollutant parameter or the method ML is above the applicable water quality criterion but the amount of the pollutant or pollutant parameter in the facility’s discharge is high enough that the method detects and quantifies the level of the pollutant or pollutant parameter in the discharge; or 3.2.2. The method has the lowest ML of the analytical methods approved under 40 C.F.R. part 136 or required under 40 C.F.R. chapter 1, subchapter N for the measured pollutant or pollutant parameter. In the case of pollutants or pollutant parameters for which there are no approved methods under 40 C.F.R. part 136 , or otherwise required under 40 C.F.R. chapter 1, subchapter N, monitoring must be conducted according to a test procedure specified in this Order for such pollutants or pollutant parameters. (40 C.F.R. 122.21(e)(3), 122.41(j)(4), 122.44(i)(1)(iv).) 4. STANDARD PROVISIONS – RECORDS 4.1. The Discharger shall retain records of all monitoring information , including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation, copies of all reports required by this Order, and records of all data used to complete the application for this Order, fo r a period of at least three (3) years from the date of the sample, measurement, report or application. This period may be extended by request of the Central Coast Water Board Executive Officer at any time. (40 C.F.R. 122.41(j)(2).) 4.2. Records of monitoring information shall include: 4.2.1. The date, exact place, and time of sampling or measurements (40 C.F.R. 122.41(j)(3)(i)); 4.2.2. The individual(s) who performed the sampling or measurements (40 C.F.R. 122.41(j)(3)(ii)); 4.2.3. The date(s) analyses were performed (40 C.F.R. 122.41(j)(3)(iii)); CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-6 4.2.4. The individual(s) who performed the analyses (40 C.F.R. 122.41(j)(3)(iv)); 4.2.5. The analytical techniques or methods used (40 C.F.R. 122.41(j)(3)(v)); and 4.2.6. The results of such analyses. (40 C.F.R. 122.41(j)(3)(vi).) 4.3. Claims of confidentiality for the following information will be denied (40 C.F.R. 122.7(b)): 4.3.1. The name and address of any permit applicant or Discharger (40 C.F.R. 122.7(b)(1)); and 4.3.2. Permit applications and included attachments, permits, and effluent data. (40 C.F.R. 122.7(b)(2).) 5. STANDARD PROVISIONS – REPORTING 5.1. Duty to Provide Information The Discharger shall furnish to the Central Coast Water Board, State Water Board, or U.S. EPA within a reasonable time, any information which the Central Coast Water Board, State Water Board, or U.S. EPA may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this Order or to determine compliance with this Order. Upon request, the Discharger shall also furnish to the Central Coast Water Board, State Water Board, or U.S. EPA copies of records required to be kept by this Order. (40 C.F.R. 122.41(h); Water Code sections 13267, 13383.) 5.2. Signatory and Certification Requirements 5.2.1. All applications, reports, or information submitted to the Central Coast Water Board, State Water Board, and/or U.S. EPA shall be signed and certified in accordance with Standard Provisions – Reporting 5.2.2, 5.2.3, 5.2.4, 5.2.5, and 5.2.6 below. (40 C.F.R. 122.41(k).) 5.2.2. All permit applications shall be signed by a responsible corporate officer. For the purpose of this section, a responsible corporate officer means: (i) A president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy- or decision- making functions for the corporation, or (ii) the manager of one or more manufacturing, production, or operating facilities, provided, the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmenta l compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures. (40 C.F.R. 122.22(a)(1).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-7 5.2.3. All reports required by this Order and other information requested by the Central Coast Water Board, State Water Board, or U.S. EPA shall be signed by a person described in Standard Provisions – Reporting 5.2.2 above, or by a duly authorized representative of that person. A person is a duly authorized representative only if: 5.2.3.1. The authorization is made in writing by a person described in Standard Provisions – Reporting 5.2.2 above (40 C.F.R. 122.22(b)(1)); 5.2.3.2. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the company. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.) (40 C.F.R. 122.22(b)(2)); and 5.2.3.3. The written authorization is submitted to the Central Coast Water Board and State Water Board. (40 C.F.R. 122.22(b)(3).) 5.2.4. If an authorization under Standard Provisions – Reporting 5.2.3 above is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of Standard Provisions – Reporting 5.2.3 above must be submitted to the Central Coast Water Board and State Water Board prior to or together with any reports, information, or applications, to be signed by an authorized representative. (40 C.F.R. 122.22(c).) 5.2.5. Any person signing a document under Standard Provisions – Reporting 5.2.2 or 5.2.3 above shall make the following certification: “I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.” (40 C.F.R. 122.22(d).) 5.2.6. Any person providing the electronic signature for documents described in Standard Provisions – 5.2.1, 5.2.2, or 5.2.3 that are submitted electronically shall meet all relevant requirements of Standard Provisions – Reporting 5.2, and shall ensure that all relevant requirements of 40 C.F.R. part 3 (Cross-Media Electronic Reporting) and 40 C.F.R. part 127 (NPDES Electronic Reporting Requirements) are met for that submission. (40 C.F.R 122.22(e).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-8 5.3. Monitoring Reports 5.3.1. Monitoring results shall be reported at the intervals specified in the Monitoring and Reporting Program (Attachment E) in this Order. (40 C.F.R. 122.41(l)(4).) 5.3.2. Monitoring results must be reported on a Discharge Monitoring Report (DMR) form or forms provided or specified by the Central Coast Water Board or State Water Board. All reports and forms must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 and comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(l)(4)(i).) 5.3.3. If the Discharger monitors any pollutant more frequently than required by this Order using test procedures approved under 40 C.F.R. part 136, or another method required for an industry-specific waste stream under 40 C.F.R. chapter 1, subchapter N, the results of such monitoring shall be included in the calculation and reporting of the data submitted in the DMR or reporting form specified by the Central Coast Water Board or State Water Board. (40 C.F.R. 122.41(l)(4)(ii).) 5.3.4. Calculations for all limitations, which require averaging of measurements, shall utilize an arithmetic mean unless otherwise specified in this Order. (40 C.F.R. 122.41(l)(4)(iii).) 5.4. Compliance Schedules Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule of this Order, shall be submitted no later than 14 days following each schedule date. (40 C.F.R. 122.41(l)(5).) 5.5. Twenty-Four Hour Reporting 5.5.1. The Discharger shall report any noncompliance which may endanger health or the environment. Any information shall be provided orally within 24 hours from the time the Discharger becomes aware of the circumstances. A report shall also be provided within five (5) days of the time the Discharger becomes aware of the circumstances. The report shall contain a description of the noncompliance and its cause; the period of noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports must include the data described above (with the exception of time of discovery) as well as the type of event (i.e., combined sewer overflow, sanitary sewer overflow, or bypass event), type of overflow structure (e.g., manhole, combined sewer overflow outfall), discharge volume untreated by the treatment works treating domestic sewage, types of human health and environmental impacts of the event, and whether the noncompliance was related to wet weather. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-9 As of December 21, 2023, all reports related to combined sewer overflows, sanitary sewer overflows, or bypass events must be submitted to the Central Coast Water Board and must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 The reports shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(6)(i).) 5.5.2. The following shall be included as information that must be reported within 24 hours: 5.5.2.1. Any unanticipated bypass that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(A).) 5.5.2.2. Any upset that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.5.3. The Central Coast Water Board may waive the above required written report on a case-by-case basis if an oral report has been received within 24 hours. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.6. Planned Changes The Discharger shall give notice to the Central Coast Water Board as soon as possible of any planned physical alterations or additions to the permitted facility. Notice is required under this provision only when (40 C.F.R. 122.41(l)(1)): 5.6.1. The alteration or addition to a permitted facility may meet one of the criteria for determining whether a facility is a new source in section 122.29(b) (40 C.F.R. 122.41(l)(1)(i)); or 5.6.2. The alteration or addition could significantly change the nature or increase the quantity of pollutants discharged. This notification applies to pollutants that are not subject to effluent limitations in this Order. (40 C.F.R. 122.41(l)(1)(ii).); or 5.7. Anticipated Noncompliance The Discharger shall give advance notice to the Central Coast Water Board of any planned changes in the permitted facility or activity that may result in noncompliance with this Order’s requirements. (40 C.F.R. 122.41(l)(2).) 5.8. Other Noncompliance The Discharger shall report all instances of noncompliance not reported under Standard Provisions – Reporting 5.3, 5.4, and 5.5 above at the time monitoring reports are submitted. The reports shall contain the information listed in Standard Provision – Reporting 5.5 above. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports shall contain the information described in Standard Provision – Reporting 5.5 and the applicable required data in appendix A to 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-10 related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(7).) 5.9 Other Information When the Discharger becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or in any report to the Central Coast Water Board, State Water Board, or U.S. EPA, the Discharger shall promptly submit such facts or information. (40 C.F.R. 122.41(l)(8).) 5.10. Initial Recipient for Electronic Reporting Data The owner, operator, or the duly authorized representative is required to electronically submit NPDES information specified in appendix A to 40 C.F.R. part 127 to the initial recipient defined in 40 C.F.R. section 127.2(b). U.S. EPA will identify and publish the list of initial recipients on its website and in the Federal Register, by state and by NPDES data group [see 40 C.F.R. 127.2(c)]. U.S. EPA will update and maintain this listing. (40 C.F.R. 122.41(l)(9).) 6. STANDARD PROVISIONS – ENFORCEMENT 6.1. The Central Coast Water Board is authorized to enforce the terms of this permit under several provisions of the Water Code, including, but not limited to, sections 13268, 13350, 13385, 13386, and 13387. 7. ADDITIONAL PROVISIONS – NOTIFICATION LEVELS 7.1. Non-Municipal Facilities Existing manufacturing, commercial, mining, and silvicultural Dischargers shall notify the Central Coast Water Board as soon as they know or have reason to believe (40 C.F.R. 122.42(a)): 7.1.1. That any activity has occurred or will occur that would result in the discharge, on a routine or frequent basis, of any toxic pollutant that is not limited in this Order, if that discharge will exceed the highest of the following "notification levels" (40 C.F.R. 122.42(a)(1)): 7.1.1.1. 100 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(1)(i)); 7.1.1.2. 200 μg/L for acrolein and acrylonitrile; 500 μg/L for 2,4 dinitrophenol and 2-methyl 4,6 dinitrophenol; and 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(1)(ii)); 7.1.1.3. Five (5) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(1)(iii)); or 7.1.1.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(1)(iv).) 7.1.2. That any activity has occurred or will occur that would result in the discharge, on a non-routine or infrequent basis, of any toxic pollutant that is not limited in this CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-11 Order, if that discharge will exceed the highest of the following “notification levels" (40 C.F.R. 122.42(a)(2)): 7.1.2.1. 500 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(2)(i)); 7.1.2.2. 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(2)(ii)); 7.1.2.3. Ten (10) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(2)(iii)); or 7.1.2.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(2)(iv).) 7.2 Publicly Owned Treatment Works (POTWs) All POTWs shall provide adequate notice to the Central Coast Water Board of the following (40 C.F.R. 122.42(b)): 7.2.1. Any new introduction of pollutants into the POTW from an indirect discharger that would be subject to sections 301 or 306 of the CWA if it were directly discharging those pollutants (40 C.F.R. 122.42(b)(1)); and 7.2.2. Any substantial change in the volume or character of pollutants being introduced into that POTW by a source introducing pollutants into the POTW at the time of adoption of the Order. (40 C.F.R. 122.42(b)(2).) 7.2.3. Adequate notice shall include information on the quality and quantity of effluent introduced into the POTW as well as any anticipated impact of the change on the quantity or quality of effluent to be discharged from the POTW. (40 C.F.R. 122.42(b)(3).) 8. CENTRAL COAST WATER BOARD STANDARD PROVISIONS 8.1. Central Coast Standard Provision – Prohibitions 8.1.1. Introduction of “incompatible wastes” to the treatment system is prohibited. 8.1.2. Discharge of high-level radiological waste and of radiological, chemical, and biological warfare agents is prohibited. 8.1.3. Discharge of “toxic pollutants” in violation of effluent standards and prohibitions established under section 307(a) of the CWA is prohibited. 8.1.4. Discharge of sludge, sludge digester or thickener supernatant, and sludge drying bed leachate to drainageways, surface waters, or the ocean is prohibited. 8.1.5. Introduction of pollutants into the collection, treatment, or disposal system by and “indirect discharger” that: 8.1.5.1. Inhibit or disrupt the treatment process, system operation, or the eventual use or disposal of sludge; or, 8.1.5.2. Flow through the system to the receiving water untreated; and, 8.1.5.3. Cause or “significantly contribute” to a violation of any requirement of this Order, is prohibited. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-12 8.1.6. Introduction of “pollutant free” wastewater to the collection, treatment, and disposal system in amounts that threaten compliance with this order is prohibited. 8.2. Central Coast Standard Provisions 8.2.1. Collection, treatment, and discharge of waste shall not create a nuisance or pollution, as defined by Water Code section 13050. 8.2.2. All facilities used for transport or treatment of wastes shall be adequately protected from inundation and washout as the result of a 100-year frequency flood. 8.2.3. Operation of collection, treatment, and disposal systems shall be in a manner that precludes public contact with wastewater. 8.2.4. Collected screenings, sludges, and other solids removed from liquid wastes shall be disposed in a manner approved by the Executive Officer. 8.2.5. Publicly owned wastewater treatment plans shall be supervised and operated by persons possessing certificates of appropriate grade pursuant to title 23 of the California Administrative Code. 8.2.6. After notice and opportunity for a hearing, this order may be terminated for cause, including, but not limited to: 8.2.6.1. Violation of any term or condition contained in this order; 8.2.6.2. Obtaining this order by misrepresentation, or by failure to disclose fully all relevant facts; 8.2.6.3. A change in any condition or endangerment to human health or environment that requires a temporary or permanent reduction or elimination of the authorized discharge; and, 8.2.6.4. A substantial change in character, location, or volume of the discharge. 8.2.7. Provisions of this permit are severable. If any provision of the permit is found invalid, the remainder of the permit shall not be affected. 8.2.8. After notice and opportunity for hearing, this order may be modified or revoked and reissued for cause, including: 8.2.8.1. Promulgation of a new or revised effluent standard or limitation; 8.2.8.2. A material change in character, location, or volume of the discharge; 8.2.8.3. Access to new information that affects the germs of the permit, including applicable schedules; 8.2.8.4. Correction of technical mistakes or mistaken interpretations of law; and, 8.2.8.5. Other causes set forth under Sub -part D of 40 C.F.R. part 122. 8.2.9. Safeguards shall be provided to ensure maximal compliance with all terms and conditions of this permit. Safeguards shall include preventative and contingency plans and may also include alternative power sources, stand-by generators, retention capacity, operative procedures, or other precautions. Preventative and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-13 contingency plans for controlling and minimizing the effect of accidental discharges shall: 8.2.9.1. Identify possible situations that could cause “upset,” “overflow,” or “bypass,” or other noncompliance. (Loading and storage areas, power outage, waste treatment unit outage, and failure of process equipment, tanks and pipes should be considered). 8.2.9.2. Evaluate the effectiveness of present facilities and procedures and describe procedures and steps to minimize or correct any adverse environmental impact resulting from noncompliance with the permit. 8.2.10. Physical Facilities shall be designed and constructed according to accepted engineering practice and shall be capable of full compliance with this order when properly operated and maintained. Proper operation and maintenance shall be described in an Operation and Maintenance Manual. Facilities shall be accessible during the wet-weather season. 8.2.11. The discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) that are installed or used by the discharger to achieve compliance with the conditions of this order. Electrical and mechanical equipment shall be maintained in accordance with appropriate practices and standards, such as NFPA 70B, Recommended Practice for Electrical Equipment Maintenance; NFPA 70E, Standard for Electrical Safety in the Workplace; ANSI/NETA MTS Standard for Maintenance: Testing Specifications for Electrical Power Equipment and Systems, or procedures established by insurance companies or industry resources. 8.2.12. If the discharger’s facilities are equipped with SCADA or other systems that implement wireless, remote operation, the discharger should implement appropriate safeguards against unauthorized access to the wireless systems. Standards such as NIST SP 800-53, Recommended Security Controls for Federal Information Systems, can provide guidance. 8.2.13. Production and use of reclaimed water is subject to the approval of the Central Coast Water Board. Production and use of reclaimed water shall be in conformance with recycling criteria established in chapter 3, title 22, of the California Administrative Code and chapter 7, division 7, of the Water Code. An engineering report pursuant to section 60323, title 22, of the California Administrative Code is required and a waiver or water recycling requirements from the Central Coast Water Board is required before reclaimed water is supplied for any use, or to any user, not specifically identified and approved either in this Order or another order issued by the Central Coast Water Board. 8.3. Central Coast Standard Provisions – General Monitoring Requirements 8.3.1. If results of monitoring a pollutant appear to violate effluent limitations based on a weekly, monthly, 30-day, or six-month period, but compliance or non-compliance cannot be validated because sampling is too infrequent, the frequency of sampling shall be increased to validate the test within the next monitoring period. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-14 The increased frequency shall be maintained until the Executive Officer agrees the original monitoring frequency may be resumed. For example, if copper is monitored annually and results exceed the six -month median numerical effluent limitation in the permit, monitoring of copper must be increased to a frequency of at least once every two months (Central Coast Standard Provisions – Definitions 1.7.13.). If suspended solids are monitored weekly and results exceed the weekly average numerical limit in the permit, monitoring of suspended solids must be increased to at least four (4) samples every week (Central Coast Standard Provisions – Definitions 1.7.14.). 8.3.2. Water quality analyses performed in order to monitor compliance with this permit shall be by a laboratory certified by the Division of Drinking Water for the constituent(s) being analyzed. Bioassay(s) performed in order to monitor compliance with this permit shall be in accord with guidelines approved by the State Water Board and the California Department of Fish and Wildlife. If the laboratory used or proposed for use by the discharger is not certified by the Division of Drinking Water or, where appropriate, the Department of Fish and Wildlife due to restrictions in the State's laboratory certification program, the discharger shall be considered in compliance with this provision provided: 8.3.2.1. Data results remain consistent with results of samples analyzed by the Central Coast Water Board; 8.3.2.2. A quality assurance program is used at the laboratory, including a manual containing steps followed in this program that is available for inspections by the staff of the Central Coast Water Board; and, 8.3.2.3. Certification is pursued in good faith and obtained as soon as possible after the program is reinstated. 8.3.3. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. Samples shall be taken during periods of peak loading conditions. Influent samples shall be samples collected from the combined flows of all incoming wastes, excluding recycled wastes. Effluent samples shall be samples collected downstream of the last treatment unit and tributary flow and upstream of any mixing with receiving waters. 8.3.4. All monitoring instruments and devices used by the discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. 8.4. Central Coast Standard Provisions – General Reporting Requirements 8.4.1. Reports of marine monitoring surveys conducted to meet receiving water monitoring requirements of the Monitoring and Reporting Program shall include at least the following information: 8.4.1.1. A description of climatic and receiving water characteristics at the time of sampling (weather observations, floating debris, discoloration, wind speed and direction, swell or wave action, time of sampling, tide height, etc.). CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-15 8.4.1.2. A description of sampling stations, including differences unique to each station (e.g., station location, grain size, rocks, shell litter, calcareous worm tubes, evident life, etc.). 8.4.1.3. A description of the sampling procedures and preservation sequence used in the survey. 8.4.1.4. A description of the exact method used for laboratory analysis. In general, analysis shall be conducted according to Central Coast Standard Provisions – 8.3.1 above, and Federal Standard Provision – Monitoring 3.2. However, variations in procedure are acceptable to accommodate the special requirements of sediment analysis. All such variations must be reported with the test results. 8.4.1.5. A brief discussion of the results of the survey. The discussion shall compare data from the control station with data from the outfall stations. All tabulations and computations shall be explained. 8.4.2. Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule shall be submitted within 14 days following each scheduled date unless otherwise specified within the permit. If reporting noncompliance, the report shall include a description of the reason, a description and schedule of tasks necessary to achieve compliance, and an estimated date for achieving full compliance. A second report shall be submitted within 14 days of full compliance. 8.4.3. The Discharger shall file a Report of Waste Discharge or secure a waiver from the Executive Officer at least 180 days before making any material change or proposed change in the character, location, or plume of the discharge. 8.4.4. Within 120 days after the Discharger discovers, or is notified by the Central Coast Water Board, that monthly average daily flow will or may reach design capacity of waste treatment and/or disposal facilities within four (4) years, the Discharger shall file a written report with the Central Coast Water Board. The report shall include: 8.4.4.1. The best estimate of when the monthly average daily dry weather flow rate will equal or exceed design capacity; and, 8.4.4.2. A schedule for studies, design, and other steps needed to provide additional capacity for waste treatment and/or disposal facilities before the waste flow rate equals the capacity of present units. In addition to complying with Federal Standard Provision – Reporting 5.2, the required technical report shall be prepared with public participation and reviewed, approved and jointly submitted by all planning and building departments having jurisdiction in the area served by the waste collection, treatment, or disposal facilities. 8.4.5. All Dischargers shall submit reports electronically to the: California Regional Water Quality Control Board Central Coast Region CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-16 centralcoast@waterboards.ca.gov 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 In addition, Dischargers with designated major discharges shall submit a copy of each document to: Regional Administrator U.S. EPA, Region 9 Attention: CWA Standards and Permits Office (WTR-5) 75 Hawthorne Street San Francisco, California 94105 8.4.6. Transfer of control or ownership of a waste discharge facility must be preceded by a notice to the Central Coast Water Board at least 30 days in advance of the proposed transfer date. The notice must include a written agreement between the existing Discharger and proposed Discharger containing specific date for transfer of responsibility, coverage, and liability between them. Whether a permit may be transferred without modification or revocation and reissuance is at the discretion of the Board. If permit modification or revocation and reissuance is necessary, transfer may be delayed 180 days after the Central Coast Water Board's receipt of a complete permit application. Please also see Federal Standard Provision – Permit Action 2.3. 8.4.7. Except for data determined to be confidential under CWA section 308 (excludes effluent data and permit applications), all reports prepared in accordance with this permit shall be available for public inspection at the office of the Central Coast Water Board or Regional Administrator of U.S. EPA. Please also see Federal Standard Provision – Records 4.3. 8.4.8. By February 1st of each year, the discharger shall submit an annual report to the Central Coast Water Board. The report shall contain the following: 8.4.8.1. Both tabular and graphical summaries of the monitoring data obtained during the previous year. 8.4.8.2. A discussion of the previous year’s compliance record and corrective actions taken, or which may be needed, to bring the discharger into full compliance. 8.4.8.3. An evaluation of wastewater flows with projected flow rate increases over time and the estimated date when flows will reach facility capacity. 8.4.8.4. A discussion of operator certification and a list of current operating personnel and their grades of certification. 8.4.8.5. The date of the facility’s Operation and Maintenance Manual (including contingency plans as described in Provision 8.2.9), the date the manual was last reviewed, and whether the manual is complete and valid for the current facility. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-17 8.4.8.6. A discussion of the laboratories used by the discharger to monitor compliance with effluent limits and a summary of performance relative to section 8.3, General Monitoring Requirements. 8.4.8.7. If the facility treats industrial or domestic wastewater and there is no provision for periodic sludge monitoring in the Monitoring and Reporting Program, the report shall include a summary of sludge quantities, analyses of its chemical and moisture content, and its ultimate destination. 8.4.8.8. If appropriate, the report shall also evaluate the effectiveness of the local source control or pretreatment program using the State Water Board's "Guidelines for Determining the Effectiveness of Local Pretreatment Program." 8.5. Central Coast Standard Provisions – General Pretreatment Provisions 8.5.1. Discharge of pollutants by "indirect dischargers” in specific industrial sub- categories (appendix C, 40 C.F.R. part 403), where categorical pretreatment standards have been established, or are to be established, (according to 40 C.F.R. chapter 1, subchapter N), shall comply with the appropriate pretreatment standards: 8.5.1.1. By the date specified therein; 8.5.1.2. Within three (3) years of the effective date specified therein, but in no case later than July 1, 1984; or, 8.5.1.3. If a new indirect discharger, upon commencement of discharge. 8.6. Central Coast Standard Provision – Enforcement 8.6.1. Any person failing to file a Report of Waste Discharge or other report as required by this permit shall be subject to a civil penalty not to exceed $5,000 per day. 8.6.2. Upon reduction, loss, or failure of the treatment facility, the Discharger shall, to the extent necessary to maintain compliance with this permit, control production or all discharges, or both, until the facility is restored or an alternative method of treatment is provided. 8.7. Central Coast Standard Provisions – Definitions (Not otherwise included in Attachment A to this Order) 8.7.1. A “composite sample" is a combination of no fewer than eight (8) individual samples obtained at equal time intervals (usually hourly) over the specified sampling (composite) period. The volume of each individual sample is proportional to the flow rate at the time of sampling. The period shall be specified in the Monitoring and Reporting Program ordered by the Executive Officer. 8.7.2. “Daily Maximum” limit means the maximum acceptable concentration or mass emission rate of a pollutant measured during a calendar day or during any 24 - hour period reasonably representative of the calendar day for purposes of sampling. It is normally compared with results based on "composite samples” except for ammonia, total chlorine, phenolic compounds, and toxicity CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-18 concentration. For all exceptions, comparisons will be made with results from a “grab sample”. 8.7.3. “Discharger", as used herein, means, as appropriate: (1) the Discharger, (2) the local sewering entity (when the collection system is not owned and operated by the Discharger), or (3) "indirect discharger" (where "Discharger" appears in the same paragraph as "indirect discharger”, it refers to the discharger.) 8.7.4. “Duly Authorized Representative" is one where: 8.7.4.1. The authorization is made in writing by a person described in the signatory paragraph of Federal Standard Provision 5.2.; 8.7.4.2. The authorization specifies either an individual or the occupant of a position having either responsibility for the overall operation of the regulated facility, such as the plant manager, or overall responsibility for environmental matters of the company; and, 8.7.4.3. The written authorization was submitted to the Central Coast Water Board. 8.7.5. A "grab sample" is defined as any individual sample collected in less than 15 minutes. "Grab samples” shall be collected during peak loading conditions, which may or may not be during hydraulic peaks. It is used primarily in determining compliance with the daily maximum limits identified in Central Coast Standard Provision – Provision 8.7.2. and instantaneous maximum limits. 8.7.6. "Hazardous substance” means any substance designated under 40 C.F.R. part 116 pursuant to section 311 of the CWA. 8.7.7. "Incompatible wastes” are: 8.7.7.1. Wastes which create a fire or explosion hazard in the treatment works; 8.7.7.2. Wastes which will cause corrosive structural damage to treatment works, but in no case wastes with a pH lower than 5.0 unless the works is specifically designed to accommodate such wastes; 8.7.7.3. Solid or viscous wastes in amounts which cause obstruction to flow in sewers, or which cause other interference with proper operation of treatment works; 8.7.7.4. Any waste, including oxygen demanding pollutants (BOD, etc.), released in such volume or strength as to cause inhibition or disruption in the treatment works and subsequent treatment process upset and loss of treatment efficiency; and, 8.7.7.5. Heat in amounts that inhibit or disrupt biological activity in the treatment works or that raise influent temperatures above 40°C (104°F) unless the treatment works is designed to accommodate such heat. 8.7.8. "Indirect Discharger” means a non-domestic discharger introducing pollutants into a publicly owned treatment and disposal system. 8.7.9. "Log Mean” is the geometric mean. Used for determining compliance of fecal or total coliform populations, it is calculated with the following equation: Log Mean = (C1 x C2 x...x Cn)1/n, CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-19 in which “n" is the number of days samples were analyzed during the period and any "C" is the concentration of bacteria (MPN/100 mL) found on each day of sampling. "n” should be five or more. 8.7.10. “Mass emission rate" is a daily rate defined by the following equations: mass emission rate (lbs/day) = 8.34 x Q x C; and, mass emission rate (kg/day) = 3.79 x Q x C, where “C" (in mg/L) is the measured daily constituent concentration or the average of measured daily constituent concentrations and “Q” (in MGD) is the measured daily flowrate or the average of measured daily flow rates over the period of interest. 8.7.11. The "Maximum Allowable Mass Emission Rate," whether for a month, week, day, or six-month period, is a daily rate determined with the formulas in paragraph 8.7.10, above, using the effluent concentration limit specified in the permit for the period and the average of measured daily flows (up to the allowable flow) over the period. 8.7.12. “Maximum Allowable Six-Month Median Mass Emission Rate" is a daily rate determined with the formulas in Central Coast Standard Provision – Provision 8.7.10, above, using the "six-month Median" effluent limit specified in the permit, and the average of measured daily flows (up to the allowable flow) over a 180-day period. 8.7.13. "Median" is the value below which half the samples (ranked progressively by increasing value) fall. It may be considered the middle value, or the average of two middle values. 8.7.14. "Monthly Average" (or "Weekly Average”, as the case may be) is the arithmetic mean of daily concentrations or of daily mass emission rates over the specified 30-day (or 7-day) period. Average = (X1 + X2 + ... + Xn) / n in which “n" is the number of days samples were analyzed during the period and “X" is either the constituent concentration (mg/l) or mass emission rate (kg/day or lbs/day) for each sampled day. “n" should be four or greater. 8.7.15. "Municipality" means a city, town, borough, county, district, association, or other public body created by or under State law and having jurisdiction over disposal of sewage, industrial waste, or other waste. 8.7.16. "Overflow" means the intentional or unintentional diversion of flow from the collection and transport systems, including pumping facilities. 8.7.17. "Pollutant-free wastewater" means inflow and infiltration, stormwaters, and cooling waters and condensates which are essentially free of pollutants. 8.7.18. "Primary Industry Category" means any industry category listed in 40 C.F.R. part 122, Appendix A. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-20 8.7.19. "Removal Efficiency" is the ratio of pollutants removed by the treatment unit to pollutants entering the treatment unit. Removal efficiencies of a treatment plant shall be determined using “Monthly averages" of pollutant concentrations (C, in mg/l) of influent and effluent samples collected about the same time and the following equation (or its equivalent): 8.7.20. "Severe property damage" means substantial physical damage to property, damage to treatment facilities which causes them to become inoperable, or substantial and permanent loss to natural resources which can reasonably be expected to occur in the absence of a "bypass”. It does not mean economic loss caused by delays in production. 8.7.21. "Sludge" means the solids, residues, and precipitates separated from, or created in, wastewater by the unit processes of a treatment system. 8.7.22. To "significantly contribute" to a permit violation means an "indirect discharger" must: 8.7.22.1. Discharge a daily pollutant loading in excess of that allowed by contract with the Discharger or by Federal, State, or Local law; 8.7.22.2. Discharge wastewater which substantially differs in nature or constituents from its average discharge; 8.7.22.3. Discharge pollutants, either alone or in conjunction with discharges from other sources, which results in a permit violation or prevents sewage sludge use or disposal; or 8.7.22.4. Discharge pollutants, either alone or in conjunction with pollutants from other sources that increase the magnitude or duration of permit violations. 8.7.23. "Toxic Pollutant" means any pollutant listed as toxic under Section 307 (a) (1) of the CWA or under 40 C.F.R. part 122, Appendix D. Violation of maximum daily discharge limitations are subject to 24-hour reporting (Federal Standard Provisions 5.5.). 8.7.24. “Zone of Initial Dilution" means the region surrounding or adjacent to the end of an outfall pipe or diffuser ports whose boundaries are defined through calculation of a plume model verified by the State Water Board. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-1 E. ATTACHMENT E – MONITORING AND REPORTING PROGRAM TABLE OF CONTENTS 1. GENERAL MONITORING PROVISIONS .................................................................E-2 2. MONITORING LOCATIONS ....................................................................................E-3 3. INFLUENT MONITORING REQUIREMENTS ..........................................................E-5 3.1. Monitoring Location INF-001 .................................................................................E-5 4. EFFLUENT MONITORING REQUIREMENTS .........................................................E-5 4.1. Monitoring Location EFF-001 ................................................................................E-5 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS .................................E-9 5.1. Whole Effluent Acute Toxicity Testing ...................................................................E-9 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable .............. E-18 7. RECYCLING MONITORING REQUIREMENTS .................................................... E-18 7.1. Monitoring Location EFF-002 .............................................................................. E-18 8. RECEIVING WATER MONITORING REQUIREMENTS ........................................ E-19 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW- 006, RSW-007, and RSW-008 .............................................................................. E-19 9. OTHER MONITORING REQUIREMENTS ............................................................. E-21 9.1. Biosolids, Monitoring, and Notification – BIO-001 ............................................... E-21 9.2. Pretreatment Monitoring ...................................................................................... E-26 9.3. Salt and Nutrient Management Plan Reporting ................................................... E-29 9.4. Volumetric Monitoring of Wastewater and Recycled Water ................................. E-30 10. REPORTING REQUIREMENTS .......................................................................... E-30 10.1. General Monitoring and Reporting Requirements ............................................. E-30 10.2. Self-Monitoring Reports (SMRs)........................................................................ E-30 10.3. Discharge Monitoring Reports (DMRs) .............................................................. E-34 10.4. Other Reports .................................................................................................... E-34 TABLE OF TABLES Table E-1. Monitoring Station Locations .......................................................................E-3 Table E-2. Influent Monitoring ......................................................................................E-5 Table E-3. Effluent Monitoring at EFF-001 ...................................................................E-6 Table E-4. Approved Test for Acute Toxicity – Fresh Water ...................................... E-10 Table E-5. Approved Tests for Chronic Toxicity – Freshwater ................................... E-14 Table E-6. Recycled Water Monitoring Requirements at EFF-002 ............................. E-18 Table E-7. Receiving Water Monitoring Requirements............................................... E-19 Table E-8. Amount of Biosolids and Frequency of Analysis ....................................... E-21 Table E-9. Biosolids Monitoring Requirements .......................................................... E-22 Table E-10. Monitoring Periods and Reporting Schedule........................................... E-31 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-2 ATTACHMENT E – MONITORING AND REPORTING PROGRAM Section 308 of the federal Clean Water Act (CWA) and sections 122.41(h), (j)-(l), 122.44(i), and 122.48 of title 40 of the Code of Federal Regulations (40 C.F.R.) require that all NPDES permits specify monitoring and reporting requirements. California Water Code sections 13267 and 13383 also authorize the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) to establish monitoring, inspection, entry, reporting, and recordkeeping requirements. This Monitoring and Reporting Program (MRP) establishes monitoring, reporting, and recordkeeping requirements that implement the federal and California laws and/or regulations. 1. GENERAL MONITORING PROVISIONS 1.1. Laboratories analyzing monitoring samples shall be certified by the State Water Resources Control Board (State Water Board), in accordance with the provision of California Water Code section 13176, and must include quality assurance/quality control data with their reports. 1.2. Samples and measurements taken as required herein shall be representative of the volume and nature of the monitored discharge. All samples shall be taken at the monitoring locations specified in this MRP and, unless otherwise specified, before the monitored flow joins or is diluted by any other waste stream, body of water, or substance. Monitoring locations shall not be changed without notification to and approval of the Central Coast Water Board. 1.3. Appropriate flow measurement devices and methods consistent with accepted scientific practices shall be selected and used to ensure the accuracy and reliability of measurements of the volume of monitored discharges. The devices shall be installed, calibrated, and maintained to ensure that the accuracy of the measurements is consistent with the accepted capability of that type of device. Devices selected shall be capable of measuring flows with a maximum deviation of less than ±10 percent from true discharge rates throughout the range of expected discharge volumes. Guidance in selection, installation, calibration, and operation of acceptable flow measurement devices can be obtained from the following references. 1.3.1. A Guide to Methods and Standards for the Measurement of Water Flow, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 421, May 1975, 96 pp. http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication421.pdf 1.3.2. Water Measurement Manual, U.S. Department of Interior, Bureau of Reclamation, Second Edition, Revised Reprint, 1974, 327 pp. https://www.usbr.gov/tsc/techreferences/mands/wmm/index.htm1.3.3. Flow Measurement in Open Channels and Closed Conduits, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 484, October 1977, 982 pp. https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication484v2.pdf CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-3 1.3.3. NPDES Compliance Inspection Manual, Chapter 6 – Flow Measurement, U.S. Environmental Protection Agency (U.S. EPA), Office of Water Enforcement, Publication Number 305-K-17-001, January 2017, 918 pp. https://www.epa.gov/compliance/compliance-inspection-manual-national- pollutant-discharge-elimination-system 1.4. All monitoring instruments and devices used by the Discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. All flow measurement devices shall be calibrated at least once per year to ensure continued accuracy of the devices. 1.5. Monitoring results, including noncompliance, shall be reported at intervals and in a manner specified in this MRP. 1.6. Unless otherwise specified by this MRP, all monitoring shall be conducted according to test procedures established at 40 C.F.R. part 136, Guidelines Establishing Test Procedures for Analysis of Pollutants. All analyses shall be conducted using the lowest practical quantitation limit achievable using the specified methodology. Where effluent limitations are set below the lowest achievable quantitation limits, pollutants not detected at the lowest practical quantitation limits will be considered in compliance with effluent limitations. Analysis for toxic pollutants listed by the California Toxics Rule shall also adhere to guidance and requirements contained in the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (2005) (SIP). 1.7. The Discharger shall ensure that the results of the Discharge Monitoring Report- Quality Assurance (DMR-QA) Study or the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board at the following address: State Water Resources Control Board; Quality Assurance Program Officer; Office of Information Management and Analysis; 1001 I Street, Sacramento, CA 95814 2. MONITORING LOCATIONS The Discharger shall establish the following monitoring locations to demonstrate compliance with the effluent limitations, discharge specifications, and other requirements in this Order: Table E-1. Monitoring Station Locations Discharge Point Name Monitoring Location Name Monitoring Location Description INF-001 Influent wastewater prior to treatment and following all significant inputs to the collection system of untreated wastewater and inflow and infiltration, where representative samples of CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-4 Discharge Point Name Monitoring Location Name Monitoring Location Description wastewater influent can be obtained prior to any plant return flows or treatment processes EFF-001 EFF-001A At a point where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to entering the discharge pipeline to San Luis Obispo Creek: 35.251533°N, 120.676817°W EFF-001B At a point at the end of the discharge pipeline where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to commingling with other waste streams or being discharged into San Luis Obispo Creek: 35.244307°N, 120.680618°W EFF-002 EFF-002 Location where a representative sample of title 22 recycled water can be collected prior to discharge to the recycled water storage tank. Receiving Water RSW-001 At Fox Canyon Road Receiving Water RSW-002 At Mission Receiving Water RSW-003 At Marsh Street Bridge Receiving Water RSW-004 50 feet upstream of effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-005 A location in San Luis Obispo Creek immediately upstream of the confluence with Prefumo Canyon Creek CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-5 Discharge Point Name Monitoring Location Name Monitoring Location Description Receiving Water RSW-006 A location in Prefumo Canyon Creek 50 feet upstream of the confluence with San Luis Obispo Creek Receiving Water RSW-007 Approximately 0.5 miles downstream from effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-008 At Higuera Street Bridge, near US 101 Biosolids BIO-001 Biosolids at the last point in the biosolids handling process where representative samples of residual solids from the treatment process can be obtained 3. INFLUENT MONITORING REQUIREMENTS 3.1. Monitoring Location INF-001 3.1.1. The Discharger shall monitor influent to the facility at INF-001 as below: Table E-2. Influent Monitoring Parameter Units Sample Type Minimum Sampling Frequency Flow Million gallons per day (MGD) Measured 1/Day Biochemical Oxygen Demand 5-day @ 20°C (BOD5)[2] Milligram per liter (mg/L) 24-hour Composite 1/Month[1] Total Suspended Solids (TSS)[2] mg/L 24-hour Composite 1/Month[1] [1] The Discharger shall report the average and maximum daily flows. [2] Collection of BOD5 and TSS samples shall occur on days that effluent samples are collected. BOD shall be monitored in the influent at the same time as it is monitored in the effluent. 4. EFFLUENT MONITORING REQUIREMENTS 4.1. Monitoring Location EFF-001 4.1.1. The Discharger shall monitor effluent discharged at Monitoring Location EFF -001 as specified in Table E-3. Except where specified, all monitoring will be performed at EFF-001A. If more than one analytical test method is listed for a given CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-6 parameter, the Discharger must select from the listed methods and corresponding Minimum Level: Table E-3. Effluent Monitoring at EFF-001 Parameter Units Sample Type Minimum Sampling Frequency Flow MGD Metered 1/Day Instantaneous Maximum Flow MGD Metered 1/Day Maximum Daily Flow Calculated 1/Month Mean Daily Flow MGD Calculated 1/Month Biochemical Oxygen Demand, 5- day (BOD5) mg/L 24-hour Composite 1/Month BOD Mass Emissions Rate pounds per day (lbs/day) Calculated 1/Month BOD5 Percent removal Calculated 1/Month pH[1] standard units Continuous or Grab 1/Day Chlorine, Total Residual[2] mg/L Continuous or Grab Grab samples shall be taken a minimum of twice per day, and within 30 minutes of any excursion above 0.1 mg/L Chlorine Used[2] lbs/day Calculated 1/Day Temperature[1] °C Continuous or Grab 5/Week Total Coliform MPN/100 mL Grab 5/Week Settleable Solids milliliter per liter (ml/L) Grab 1/Week Ammonia (as N) [3] mg/L Grab 1/Week Un-ionized Ammonia (as N) [1] mg/L Calculated 1/Week Total Suspended Solids (TSS) mg/L 24-hr. composite 1/Week TSS Percent removal Calculated 1/Week Turbidity Nephelo- metric Turbidity 24-hr. composite 1/10 days CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-7 Parameter Units Sample Type Minimum Sampling Frequency Units (NTU) Dissolved Oxygen mg/L Grab 1/Month Color Color units Grab 1/Month Oil and Grease mg/L Grab 1/Month Total Kjeldahl Nitrogen (TKN) (as N) mg/L Grab 1/Month Chlorodibromomethane (aka Dibromochloromethane) μg/L 24-hr. composite 1/Month[4] Chloroform μg/L 24-hr. composite 1/Month[4] Dichlorobromomethane μg/L 24-hr. composite 1/Month[4] Methylene Chloride μg/L 24-hr. composite 1/Month[4] Pentachlorophenol μg/L 24-hr. composite 1/Month[4] Nitrate (as N) mg/L Grab 1/Month Nitrite (as N) mg/L Grab 1/Month Methylene Blue Active Substances (MBAS) mg/L 24-hr. composite 1/Month[4] Molybdenum mg/L Grab 1/Month Dissolved Orthophosphate (as P) mg/L Grab 1/Month Total Phosphate (as P) mg/L Grab 1/Month Total Dissolved Solids (TDS) mg/L Grab 1/Month Sodium mg/L Grab 1/Month Chloride mg/L Grab 1/Month Sulfate mg/L Grab 1/Month Hardness (CaCO3)[5] mg/L 24-hr. composite 1/Quarter Boron mg/L Grab 1/Year (in October) Cobalt mg/L Grab 1/Year (in October) Iron mg/L Grab 1/Year (in October) Lithium mg/L Grab 1/Year (in October) Manganese mg/L Grab 1/Year (in October) Vanadium mg/L Grab 1/Year (in October) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-8 Parameter Units Sample Type Minimum Sampling Frequency Acute Toxicity[6] ”Pass/Fail” and % Effect Grab 1/Year Chronic Toxicity[6] “Pass/Fail and % Effect” Grab 1/Month[7] California Toxics Rule (CTR) Pollutants[8], [9] μg/L 24-Hour composite 1/Year (in October) Title 22 Pollutants[10], [11] μg/L 24-Hour composite 1/Year (in October) [1] Temperature and pH are to be measured at the same time the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] Sampling shall be concurrent with sampling of receiving water for ammonia. [4] If no exceedances of the effluent limitation occur for a minimum of 12 consecutive months of monitoring then the frequency of monitoring shall be reduced to quarterly. Subsequently, if an exceedance of the effluent limitation occurs during quarterly monitoring, the monitoring frequency shall return to monthly. The Discharger must notify the Central Coast Water Board of the change in monitoring frequency . [5] Hardness monitoring will occur on the same day and time as the California Toxics Rule (CTR) pollutants to allow for conversion from total recoverable to dissolved for hardness dependent metals. [6] Whole effluent acute and chronic toxicity monitoring shall be conducted according to the requirements established in sections 5.1 and 5.2, respectively, of this MRP. [7] Once per year, in October, chronic toxicity monitoring must be performed at EFF- 001B instead of at EFF-001A. [8] The California Toxics Rule (CTR) pollutants are those listed by the CTR at 40 C.F.R. 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). The Discharger shall instruct its analytical laboratory to establish calibration standards so that the Minimum Levels (MLs) presented in Appendix 4 of the SIP are the lowest calibration standards. The Discharger and its analytical laboratory shall select MLs which are below applicable water quality criteria of the CTR; and when applicable water quality criteria are below all MLs, the Discharger and its analytical laboratory shall select the lowest ML. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-9 [9] Monitoring for the CTR pollutants in effluent shall occur simultaneously with monitoring required for the CTR pollutants in receiving water. [10] The title 22 pollutants are those pollutants for which Maximum Contaminant Levels (MCLs) have been established at title 22, division 4, chapter 15, sections 64431 (inorganic chemicals) and 64444 (organic chemicals) of the California Code of Regulations. Where these pollutants are included in other groups of pollutants (CTR Priority Pollutants), monitoring does not need to be duplicated. Analytical methods shall adhere to the Detection Limits for Purposes of Reporting (DLRs) established by title 22 of the California Code of Regulations, division 4, chapter 15, sections 64432 and 64445.1. [11] Monitoring for the title 22 pollutants in effluent shall occur simultaneously with monitoring required for the title 22 pollutants in receiving water. 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS 5.1. Whole Effluent Acute Toxicity Testing 5.1.1. Routine Acute Toxicity Monitoring Frequency. The Discharger shall conduct at least one acute aquatic toxicity test using the most sensitive species every calendar year during which there is expected to be at least 15 days of discharge in at least one calendar quarter. For the purposes of acute toxicity, the calendar year starts from the initiation of routine monitoring. If the Discharger is unable to sample within the calendar year due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar year was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. 5.1.2. Discharge In-stream Waste Concentration (IWC) for Acute Toxicity. The IWC for this discharge is 100 percent effluent. 5.1.3. Most Sensitive Species. The test species used for acute toxicity testing shall be the most sensitive species. To be consistent with previous Order R3-2014-0033, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct acute toxicity testing from the effective date of this permit until the completion of the required acute species sensitivity screening detailed in section 5.1.6 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation, and the Central Coast Water Board determines that the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-10 Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.1.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.1.5. Acute Freshwater Species and Test Methods. The Discharger shall conduct acute toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136). Approved tests methods for acute toxicity are listed in Table E-4 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-4. Approved Test for Acute Toxicity – Fresh Water Species Effect Test Duration (hours) Test Method Fathead Minnow (Pimephales promelas) Survival 96 Survival Test Method 2000.0 Water Flea (Ceriodaphnia dubia) Survival 48 Survival Test Method 2002.0 5.1.6. Acute Species Sensitivity Screening. The Discharger shall conduct one species sensitivity screening test during the Order’s first required sample collection for acute toxicity. The Discharger shall collect a single effluent sample to initiate and concurrently conduct two toxicity tests using the fish and invertebrate species referenced in Table E-4 above. This sample shall also be analyzed for the parameter(s) required on a mon thly and quarterly frequency in Table E-3, during that given month. Samples for the species sensitivity screening shall be analyzed using the TST approach. The species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-11 than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. 5.1.7. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.1.7.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent Effect” for acute toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.80 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.1.7.2. If the effluent toxicity test does not meet all test acceptability criteria (TAC) specified in the referenced test method, Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136) then the Discharger must resample and re-test within 7 days. 5.1.7.3. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.1.7.4. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.1.8. Notification. The Discharger shall notify the Central Coast Water Board of an exceedance of the acute toxicity trigger of 90 percent survival as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-12 Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.1.9. Accelerated Monitoring Requirements. If the result of any acute toxicity test fails to meet the single test minimum trigger (70 percent survival), and the testing meets all TAC, the Discharger shall take two more samples, one within 14 days and one within 21 days following receipt of the initial sample result. If any one of the additional samples do not comply with the three -sample median minimum limitation (90 percent survival), the Discharger shall initiate a Toxicity Reduction Evaluation (TRE) in accordance with section 5.4 of the MRP. If the two additional samples are in compliance with the acute toxicity requirement and testing meets all TAC, then a TRE will not be required. 5.1.10. Reporting. The Self-Monitoring Report (SMR) shall include a full laboratory report for each toxicity test (WET report). The WET report shall be prepared using the format and content of section 12 (Report Preparation) of Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 5th edition or subsequent editions), including: 5.1.10.1. The toxicity test results in percent (%) survival for the 100 percent effluent sample. 5.1.10.2. The toxicity test results for the TST approach, reported as “Pass” or “Fail” and “Percent Effect” at the acute toxicity IWC for the discharge. 5.1.10.3. Water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.1.10.4. TRE/Toxicity Identification Evaluation (TIE) results. The Executive Officer shall be notified no later than 30 days from completion of each aspect of TRE/TIE analyses. 5.1.10.5. Statistical program (e.g., TST calculator, CETIS, etc.) output results for each toxicity test. 5.2. Chronic Toxicity Monitoring Requirements – Monitoring Location EFF-001 5.2.1. Routine Chronic Toxicity Monitoring Frequency. The Discharger shall conduct at least one chronic aquatic toxicity test every calendar month during which there is expected to be at least 15 days of discharge. Initiation of the routine monitoring test shall be at a time that would allow any required Med ian Monthly Effluent Limitation (MMEL) compliance tests to be initiated within the same calendar month as the routine monitoring test. For routine chronic toxicity monitoring, the Discharger shall conduct at least one chronic toxicity test using the most sensitive species each calendar month during which there is expected to be at least 15 days of discharge. For the purposes of chronic toxicity, the calendar month starts from the initiation of routine monitoring. The Discharger shall ensure there is sufficient time to perform the MMEL compliance testing within the defined calendar month, should the initial toxicity test result in a “Fail”. If the Discharger is unable to sample within the calendar CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-13 month due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar month was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. The Discharger may request to reduce the monitoring frequency from once per calendar month to once per calendar quarter if all of the following conditions are met: 1) the toxicity requirements in this permit have been followed; and 2) there were no violations of the MMEL or Maximum Daily Effluent Limitation (MDEL) for chronic toxicity within the last five years. If a chronic toxicity test results in a “Fail” at the IWC during reduced monitoring, the frequency is automatically increased back to once per month for a period of five years. 5.2.2. Discharge In-stream Waste Concentration (IWC). The IWC for this discharge is 100 percent effluent. 5.2.3. Most Sensitive Species. The test species used for chronic toxicity testing shall be the most sensitive species. To be consistent with Order No. R3 -2014-003, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct chronic toxicity testing from the effective date of this permit until the completion of the required chronic species sensitivity screening described in section 5.2.7 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation and the Central Coast Water Board determines that the Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.2.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.2.5. Chronic Freshwater Species and Test Methods. The Discharger shall conduct chronic toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002; Table IA, 40 C.F.R. part 136). Approved CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-14 tests methods for chronic toxicity are listed in Table E-5 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-5. Approved Tests for Chronic Toxicity – Freshwater Species Effect Test Duration (days) Test Method Fathead Minnow (Pimephales promelas) Larval Survival and Growth 7 Larval Survival and Growth Test Method 1000.0 Water Flea (Ceriodaphnia dubia) Survival and Reproduction 6 to 8 days Survival and Reproduction Test Method 1002.0 Green Alga (Selenastrum capricornutum) Growth 4 days Growth Test Method 1003.0 5.2.6. Median Monthly Effluent Limitation (MMEL) Compliance Monitoring. If a chronic toxicity test conducted during routine monitoring results in a “Fail” at the IWC, the Discharger shall conduct a maximum of two chronic toxicity MMEL compliance tests. The MMEL compliance tests shall be initiated within the same calendar month that the first routine chronic toxicity test was initiated that resulted in a “Fail” at the IWC. If the first chronic toxicity MMEL compliance test results in a “Fail” at the IWC, then the second chronic toxicity MMEL compliance test is not required. 5.2.7. Chronic Species Sensitivity Screening. The Discharger shall conduct four species sensitivity screening tests within 18 months of the effective date of this permit and four species sensitivity screening tests within one year of submitting the ROWD for the Facility, with one set of screenings conducted in each quarter for four consecutive quarters. For each set of species sensitivity screenings, the Discharger shall collect a single effluent sample to initiate and concurrently conduct three toxicity tests using the fish, invertebrate, and alga species referenced in Table E-5 above. This sample shall also be analyzed for the parameter(s) required on a monthly and quarterly frequency in Table E -3, during that given month. As allowed under the test method for the Ceriodaphnia dubia and the Pimephales promelas, a second and third sample shall be collected for use as test solution renewal water as the seven-day toxicity test progresses. Samples for the species sensitivity screening shall be analyzed using the TST approach. After the fourth set of species sensitivity screening, the species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-15 repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. During the calendar month, toxicity tests used to determine the most sensitive test species shall be reported as effluent compliance monitoring results for the MDEL and MMEL for chronic toxicity. 5.2.8. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.2.8.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent (%) Effect” for chronic toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.2.8.2. The MDEL for chronic toxicity is exceeded and a violation will be flagged when a toxicity test during routine monitoring results in “Fail” for the sub -lethal endpoint in accordance with the TST approach and the “Percent Effect” is greater than or equal to 50 percent for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. 5.2.8.3. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. 5.2.8.4. If the effluent toxicity test does not meet all TAC specified in the referenced test method, Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002) then the Discharger must resample and re-test within 14 days. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-16 5.2.8.5. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.2.8.6. Monthly reference toxicant testing is sufficient if in accordance with Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). All reference toxicant test results should be reviewed and reported using the effects concentration at 25 percent (EC25). 5.2.8.7. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.2.9. Notification. The Discharger shall notify the Central Coast Water Board of a violation of a toxicity MDEL or MMEL as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.2.10. Routine Reporting. The SMR shall include a full laboratory report for each chronic toxicity test. This report shall be prepared using the format and content of the test methods manual in section 10 of Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002), Report Preparation, and shall include: 5.2.10.1. The valid toxicity test results for the TST statistical approach, reported as “Pass” or “Fail” and “Percent Effect” at the chronic toxicity IWC for the discharge. All toxicity test results (whether identified as valid or otherwise) conducted during the calendar month shall be reported on the SMR due date specified in Table E-10. 5.2.10.2. Summary water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.2.10.3. The statistical analysis used in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10- 003, 2010) Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. 5.2.10.4. Statistical program (e.g., TST calculator, CETIS, etc.) output results, including graphical plots, for each toxicity test. 5.2.10.5. Tabular data and graphical plots clearly showing the laboratory’s performance for the reference toxicant for the previous 20 tests and the laboratory’s performance for the control mean, control standard deviation, and control coefficient of variation for the previous 12-month period. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-17 5.2.10.6. Any additional quality assurance/quality control (QA/QC) documentation or any additional chronic toxicity-related information, upon written request from the Central Coast Water Board. 5.3. Accelerated Monitoring Requirements 5.3.1. When acute toxicity is detected in the effluent, or when the chronic toxicity effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all TAC, the Discharger shall initiate accelerated monitoring to confirm the effluent toxicity. 5.3.2. The Discharger shall implement an accelerated monitoring frequency consisting of performing three toxicity tests in a six-week period following the first failed test results. 5.3.3. If implementation of the generic Toxicity Reduction Evaluation (TRE) Work Plan indicates the source of the exceedance of the effluent limitation or toxicity trigger (for instance, a temporary plant upset), then only one additional test is necessary. If exceedance of the effluent limitation or toxicity trigger is detected in this test, the Discharger will continue with accelerated monitoring requirements or implement the Toxicity Identification and Toxicity Reduction Evaluations. 5.3.4. If none of the three tests indicated exceedance of the effluent limitation or toxicity trigger, then the Discharger may return to the normal testing frequency. 5.4. Toxicity Identification Evaluations (TIE) and Toxicity Reduction Evaluation (TRE) Process 5.4.1. A TIE shall be triggered if testing from the accelerated monitoring frequency indicates any of the following: 5.4.1.1. Two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. 5.4.1.2. The TIE shall be initiated within 15 days following failure of the second accelerated monitoring test. 5.4.1.3. If a TIE is triggered prior to the completion of the accelerated testing, the accelerated testing schedule may be terminated, or used as necessary in performing the TIE. 5.4.2. The TIE shall be conducted to identify and evaluate toxicity in accordance with procedures recommended by the U.S. EPA, which include the following: 5.4.2.1. Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents, Phase I, (U.S. EPA, 1992a); 5.4.2.2. Methods for Aquatic Toxicity Identification Evaluations: Phase I Toxicity Characterization Procedures, Second Edition (U.S. EPA, 1991a); 5.4.2.3. Methods for Aquatic Toxicity Identification Evaluations: Phase II Toxicity Identification Procedures for Sampling Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993a); and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-18 5.4.2.4. Methods for Aquatic Toxicity Identification Evaluations: Phase III Toxicity Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993b). 5.4.3. As part of the TIE investigation, the Discharger shall be required to implement its TRE Work Plan. The Discharger shall take all reasonable steps to control toxicity once the source of the toxicity is identified. A failure to conduct required toxici ty tests or a TRE within a designated period shall result appropriate enforcement action. Recommended guidance in conducting a TRE includes the following: 5.4.3.1. Toxicity Reduction Evaluation Guidance for Municipal Wastewater Treatment Plants, August 1999, EPA/833B-99/002; and 5.4.3.2. Clarifications Regarding Toxicity Reduction and Identification Evaluations in the National Pollutant Discharge Elimination System Program dated March 27, 2001, U.S. EPA Office of Wastewater Management, Office of Regulatory Enforcement. 5.4.4. The Central Coast Water Board may also require the Discharger conduct a TRE if other information indicates toxicity (e.g., results of additional monitoring, results of monitoring at a higher concentration than the IWC, fish kills, intermittent recurring toxicity), or if there is no effluent available to complete routine monitoring, a MMET test or a MMEL Compliance Test. 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable 7. RECYCLING MONITORING REQUIREMENTS 7.1. Monitoring Location EFF-002 7.1.1. The Discharger shall monitor recycled water at Monitoring Location EFF-002 as described below: Table E-6. Recycled Water Monitoring Requirements at EFF-002 Parameter Units Sample Type Minimum Sampling Frequency[3] Daily Flow MGD Metered Continuous Total Coliform MPN/100 mL Grab 1/Day Turbidity[1] NTU Metered Continuous pH standard units Grab 1/Day Total Chlorine Residual[2] mg/L Metered Continuous [1] Turbidity to be sampled immediately downstream of the membrane bioreactors. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-19 the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] Monitoring is not required during periods recycled water is not being produced for use outside of the Facility. The Discharger shall specify within the SMR if production of recycled water took place during the monitoring period. 7.1.2. In the event the Producer is unable to comply with the conditions of the water recycling requirements and prohibitions, the Producer shall immediately notify the Central Coast Water Board by telephone and submit a written follow-up report with two weeks of the noncompliance. The written report shall include pertinent information explaining reasons for the noncompliance and shall indicate what steps are being taken to prevent the problems from recurring. 7.1.3. An annual self-monitoring report shall be submitted to the Central Coast Water Board by April 1 of the following year. The report shall include the following: 7.1.3.1. A letter transmitting self-monitoring reports shall accompany each report. The letter shall include a discussion of violations found during the reporting period and actions taken or planned for correcting noted violations, such as operation or facility modifications. If the Producer has previously submitted a report describing corrective actions or a time schedule for implementing corrective actions, reference to the previous correspondence will be satisfactory. The transmittal letter shall contain a statement by the Producer or the Producer’s authorized agent, under penalty of perjury, that to the best of the signer’s knowledge the report is true, accurate, and complete. 7.1.3.2. Tabulations of the results of each required analysis by the Producer specified in Table E-6 by date, time, type of sample, and station. 8. RECEIVING WATER MONITORING REQUIREMENTS 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW-008 8.1.1. The Discharger shall monitor the receiving water at Monitoring Locations RSW - 001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW- 008 as follows: Table E-7. Receiving Water Monitoring Requirements Parameter Units Sample Type Sampling Station [1] Minimum Sampling Frequency Flow[2] CFS Instantaneous 4, 5, 7, 8 1/Month Flow MGD Estimated 4, 5, 7, 8 1/Month Turbidity[2] NTU Grab 4, 5, 1/Month Color[2] Color units Grab 4, 5 1/Month CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-20 Parameter Units Sample Type Sampling Station [1] Minimum Sampling Frequency pH[2][4] standard units (s.u.) Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Temperature[4] °C Grab 4, 5 1/Month Un-ionized Ammonia (as N) [4] mg/L Calculated 4, 5 1/Month Nitrate (as N) mg/L Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Total Phosphate (as P) mg/L Grab 5, 7, 8 1/Month Ammonia, Total (as N) [3] mg/L Grab 5, 7, 8 1/Month Total Kjeldahl Nitrogen (as N) mg/L Grab 5, 7, 8 1/Month Total Dissolved Solids (TDS) mg/L Grab 4, 5, 7, 8 1/Month Chloride mg/L Grab 4, 5, 7, 8 1/Month Sulfate mg/L Grab 4, 5, 7, 8 1/Month Sodium mg/L Grab 4, 5, 7, 8 1/Quarter Boron mg/L Grab 4, 5, 7, 8 1/Quarter Hardness, as CaCO3 mg/L Grab 4, 5, 7, 8 1/Quarter Molybdenum mg/L Grab 4, 5, 7, 8 1/Year Methylene Blue Activated Substances mg/L Grab 4, 5, 7, 8 1/Year E. coli MPN/100 mL Grab 4, 5, 7, 8 1/Quarter CTR Pollutants[5], [6] µg/L Grab 4, 5 1/Year Title 22 Pollutants[7], [8] µg/L Grab 4, 5 1/Year [1] Samples shall be obtained only when safe to do so. [2] The San Luis Obispo Creek flow rate shall be used to determine the upstream and downstream stations where these constituents shall be monitored as follows: If the creek flows underground between Monitoring Location RSW-002 and the discharge point, samples shall be obtained from Monitoring Locations RSW-002. If the creek flows aboveground from Monitoring Location RSW-002 to the discharge point, samples shall be obtained from Monitoring Location RSW-004. In either case, Monitoring Location RSW-005 shall be the downstream location. [3] Sampling shall be concurrent with sampling of effluent for ammonia. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-21 [4] Temperature and pH are to be measured at the same time that the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [5] The CTR pollutants are those listed by the CTR at 40 CFR 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). [6] Monitoring of receiving water for the CTR pollutants shall occur simultaneously with effluent monitoring for the CTR pollutants. [7] The title 22 pollutants are those for which primary MCLs have been established and which are listed in sections 64431-A and 64444-A of the California Code of Regulations, title 22, division 4, chapter 15. Where these pollutants are also identified as CTR Priority Pollutants, monitoring does not need to be duplicated. [8] Monitoring of receiving water for the title 22 Pollutants shall occur simultaneously with effluent monitoring for title 22 pollutants. 9. OTHER MONITORING REQUIREMENTS 9.1. Biosolids, Monitoring, and Notification – BIO-001 9.1.1. A representative sample of biosolids shall be obtained from the last point in the handling process (i.e., in the drying beds just prior to removal or from a pond bottom). All constituents shall be analyzed annually for total concentrations for comparison with Total Threshold Limit Concentration (TTLC) criteria. The Waste Extraction Test shall be performed on any constituent when the total concentration of the waste exceeds ten times the Soluble Threshold Limit Concentration (STLC) for that substance. Twelve (12) discrete representative samples shall be collected at separate locations in the biosolids ready for disposal. These 12 samples shall be composited to form one (1) sample for constituent analysis. For accumulated, previously untested biosolids, the Discharger shall develop a representative sampling plan including number and location of sampling points and collect representative samples. The analysis shall test for the metals required in 40 C.F.R. 503.16 (for land application) or 503.26 (for surface disposal), using the methods in Test Methods for Evaluating Solid Waste, Physical/Chemical Methods (U.S. EPA Publication SW-846, all applicable editions and updates), as required in 503.8(b)(4), at the minimum frequencies established therein, provided in the table below. Table E-8. Amount of Biosolids and Frequency of Analysis Amount[1] (dry metric tons/365-day period) Minimum Sampling Frequency[2] Greater than zero, but less than 290 Once per year Equal to or greater than 290 but less than 1,500 Once per quarter (four times per year) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-22 Amount[1] (dry metric tons/365-day period) Minimum Sampling Frequency[2] Equal to or greater than 1,500 but less than 15,000 Once per sixty days (six times per year) Greater than 15,000 Once per month (twelve times per year) [1] For land application, either the amount of bulk biosolids applied to the land or the amount prepared for sale or give-away in a bag or other container for application to the land (dry weight basis). If the Discharger’s biosolids are directly land applied without further treatment by another preparer, biosolids shall also be tested for organic-N, ammonium-N, and nitrate-N at the frequencies required. For surface disposal, the amount of biosolids placed on an active sludge unit (dry weight basis). [2] Test results shall be expressed in mg pollutant per kg biosolids on a 100% dry weight basis. With U.S. EPA approval the amount of biosolids and minimum sampling frequency can coincide with the testing regiment implemented for Cal recycle. Biosolids shall be analyzed for the constituents in the table below. Table E-9. Biosolids Monitoring Requirements Parameter Units Sample Type Minimum Sampling Frequency Quantity Removed Tons or yd3 Measured During Removal Location of Reuse/Disposal General Public or Specific Site -- -- Moisture Content Percent Grab Per Table E-8 (above) pH standard units Grab Per Table E-8 (above) Total Kjeldahl Nitrogen mg/kg[1] Grab Per Table E-8 (above) Ammonia (as N) mg/kg[1] Grab Per Table E-8 (above) Nitrite (as N) mg/kg[1] Grab Per Table E-8 (above) Total Phosphorus mg/kg[1] Grab Per Table E-8 (above) Oil and Grease mg/kg[1] Grab Per Table E-8 (above) Arsenic mg/kg[1] Grab Per Table E-8 (above) Boron mg/kg[1] Grab Per Table E-8 (above) Cadmium mg/kg[1] Grab Per Table E-8 (above) Copper mg/kg[1] Grab Per Table E-8 (above) Chromium (Total) mg/kg[1] Grab Per Table E-8 (above) Lead mg/kg[1] Grab Per Table E-8 (above) Mercury mg/kg[1] Grab Per Table E-8 (above) Molybdenum mg/kg[1] Grab Per Table E-8 (above) Nickel mg/kg[1] Grab Per Table E-8 (above) Selenium mg/kg[1] Grab Per Table E-8 (above) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-23 Parameter Units Sample Type Minimum Sampling Frequency Zinc mg/kg[1] Grab Per Table E-8 (above) [1] Total sample (including solids and any liquid portion) to be analyzed and results reported as mg/kg based on the dry weight of the sample. 9.1.2. Prior to land application, the Discharger shall demonstrate that the biosolids meet Class A or Class B pathogen reduction levels by one of the methods listed in 40 C.F.R. 503.32 (unless transferred to another preparer who demonstrates pathogen reduction). Prior to disposal in a surface disposal site, the Discharger shall demonstrate that the biosolids meet Class B levels or shall ensure that the site is covered at the end of each operating day. If pathogen reduction is demonstrated using a “Process to Significantly/Further Reduce Pathogens “(PFRP), the Discharger shall maintain daily records of the operating parameters to achieve this reduction. The following applies when biosolids from the Discharger are directly land applied as Class B, without further treatment by a second preparer. If the Discharger demonstrates pathogen reduction by direct testing for fecal coliforms and/or pathogens, samples must be drawn at the frequency in the Amount/Frequency table above. If the Discharger demonstrates Class B pathogen reduction by testing for fecal coliform, at least seven grab samples must be drawn and analyzed during each monitoring event, and a geometr ic mean calculated from these seven samples. If the Discharger demonstrates Class A pathogen reduction by testing for fecal coliform and/or salmonella, plus one of the PFRP processes or testing for enteric viruses and helminth ova at least four samples of fecal coliform or salmonella must be drawn during each monitoring event. All four samples must meet the limits specified in 503.32(a). 9.1.3. For biosolids that are land applied or placed in a surface disposal site, the Discharger shall track and keep records of the operational parameters used to achieve Vector Attraction Reduction requirements in 40 C.F.R. 503.33(b). 9.1.4. Class 1 facilities (facilities with pretreatment programs or others designated as Class 1 by the Regional Administrator) and federal facilities with greater than five million gallons per day (MGD) influent flow shall sample biosolids for pollutants listed under CWA section 307(a), as required in the pretreatment section of the permit for Publicly Owned Treatment Works (POTWs) with pretreatment programs. Class 1 facilities and federal facilities greater than 5 MGD shall test dioxins/dibenzofurans using a detection limit of less than one pg/g at the time of their next priority pollutant scan if they have not done so within the past five years, and once per five years thereafter. 9.1.5. The biosolids shall be tested annually, or more frequently if necessary, to determine hazardousness. All constituents regulated under title 22 California Code or Regulations, division 5, chapter 11, article 3 shall be analyzed for comparison with TTLC criteria. The waste extraction test shall be performed on CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-24 any constituent when the total concentration of the waste exceeds ten times the STLC limit for that substance. 9.1.6. If biosolids are placed in a surface disposal site (dedicated land disposal site or monofill), a qualified groundwater scientist shall develop a groundwater monitoring program for the site, or shall certify that the placement of biosolids on the site will not contaminate an aquifer. 9.1.7. Biosolids placed in a municipal landfill shall be tested by the Paint Filter Liquids Test (U.S. EPA Method 9095) at the frequency determined by Table E-9, or more often if necessary, to demonstrate that there are no free liquids. 9.1.8. The Discharger, either directly or through contractual agreements with their biosolids management contractors, shall comply with the following notification requirements: 9.1.8.1. Notification of non-compliance. The Discharger shall notify U.S. EPA Region 9, the State Water Board, and the Regional Water Board located in the region where the biosolids are used or disposed, of any non-compliance within 24 hours if the noncompliance may seriously endanger health or the environment. For other instances of non-compliance, the Discharger shall notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance in writing within five working days of becoming aware of the non -compliance. The Discharger shall require their biosolids management contractors to notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance within the same time frames. 9.1.8.2. If biosolids are shipped to another state or Native American lands, the Discharger must send notice at least 60 days prior to the shipment to the permitting authorities in the receiving state or Native American land (the U.S. EPA Regional Office for that area and the State/Native American authorities). 9.1.8.3. For land application (in cases where Class B biosolids are directly applied without further treatment): Prior to reuse of any biosolids from the Discharger’s facility to a new or previously unreported site, the Discharger shall notify U.S. EPA, the Central Coast Water Board, and any other affected Regional Water Board. The notification shall include description of the crops or vegetation to be grown, proposed loading rates and determination of agronomic rates. If any biosolids within a given monitoring period do not meet 40 C.F.R. 503.13 metals concentrations limits, the Discharger (or its contractor) must pre-notify U.S. EPA, and determine the cumulative metals loading to that site to date, as required in 40 C.F.R. 503.12. The Discharger shall notify the applier of all the applier’s requirements under 40 C.F.R. part 503, including the requirement that the applier certify that the management practices, site restrictions, and any applicable vector attraction reduction requirements have been met. The Discharger shall require the applier to certify at the end of 38 months following application of Class B biosolids that the harvesting restrictions in effect for up to 38 months have been met. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-25 9.1.8.4. For surface disposal: Prior to disposal to a new or previously unreported site, the Discharger shall notify U.S. EPA and the Central Coast Water Board. The notice shall include a description and a topographic map of the proposed site, depth to ground water, whether the site is lined or unlined, site operator, site owner, and any State or local permits. The notice shall describe procedures for ensuring public access and grazing restrictions for three years following site closure. The notice shall include a ground water monitoring plan or description of why ground water monitoring is not required. 9.1.9. The Discharger shall submit an annual biosolids report to the U.S. EPA Region 9 Biosolids Coordinator and Central Coast Water Board by February 19th of each year (per U.S. EPA guidance and 40 C.F.R. part 503) for the period covering the previous calendar year. This report shall include: 9.1.9.1. Annual biosolids removed in dry tons and percent solids. 9.1.9.2. If appropriate, a narrative description of biosolids dewatering and other treatment processes, including process parameters, including a schematic diagram showing biosolids handling facilities. For example, if drying beds are used, report depth of application and drying time. If composting is used, report the temperature achieved and duration. 9.1.9.3. A description of disposal methods, including the following information as applicable related to the disposal methods used at the facility. If more than one method is used, include the percentage and tonnage of annual biosolids production disposed by each method. 9.1.9.3.1. For landfill disposal include: 1) the Regional Water Board waste discharge requirement (WDR) numbers that regulate the landfills used, 2) the present classifications of the landfills used, 3) the results of any ground water monitoring, 4) certifications of management practices, and 5) the names and locations of the facilities receiving biosolids. 9.1.9.3.2. For land application include: 1) the location of the site(s), 2) the Regional Water Board's WDR numbers that regulate the site(s), 3) the application rate in lbs/acre/year (specify wet or dry), 4) certifications of management practices and site restrictions, and 5) subsequent uses of the land. 9.1.9.3.3. For offsite application by a licensed hauler and composter include: 1) the name, address and U.S. EPA license number of the hauler and composter. 9.1.9.4. Copies of analytical data required by other agencies (i.e. U.S. EPA or County Health Department) and licensed disposal facilities (i.e. landfill, land application, or composting facility) for the previous year. 9.1.9.5. Descriptions of pathogen reduction methods and vector attraction reduction methods. Including supporting time and temperature data, and certifications, as required in 40 C.F.R. 503.17 and 503.27. 9.1.9.6. Names mailing address, and street addresses of persons who received biosolids for storage, further treatment, disposal in a municipal waste landfill, or CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-26 for other use or disposal methods not covered above, and amounts delivered to each. 9.1.9.7. For all biosolids used or disposed at the Discharger’s facility, the site and management practice information and certification required in 40 C.F.R. 503.17 and 503.27. 9.1.9.8. For all biosolids temporarily stored, the information required in 40 C.F.R. 503.20 is required to demonstrate temporary storage. 9.1.9.9. Reports shall be submitted in electronically using EPA’s Central Data Exchange website at CDX Home | Central Data Exchange | US EPA (cdx.epa.gov). A PDF copy can be printed and sent to: Executive Officer Central Coast Water Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 9.2. Pretreatment Monitoring By February 1 of each year, the Discharger shall submit an Annual Report to the State Water Board, Central Coast Water Board, and U.S. EPA describing the Discharger’s pretreatment activities over the previous 12 months. In the event that the Discharger is not in compliance with any pretreatment condition of this Order or resulting from pretreatment audits or compliance inspections, then the Discharger shall also include the reasons for noncompliance and state how and when the Discharger will comply with such conditions and requirements. This report shall contain, but not be limited to, the following information: 9.2.1. A summary of analytical results from representative, flow-proportioned, 24-hour composite sampling of the plant's effluent and sludge as provided in the relevant sections of this MRP. The Discharger shall also provide any influent, effluent, or sludge monitoring data for nonpriority pollutants which the Discharger believes may be causing or contributing to interference, pass-through, or adversely impacting sludge quality. Sampling and analysis shall be performed in accordance with the techniques prescribed in 40 C.F.R. part 136 and amendments thereto. 9.2.2. A discussion of upset, interference, or pass-through incidents, if any, at the POTW, which the Discharger knows or suspects were caused by industrial users of the POTW system. The discussion shall include the reasons why incidents occurred, corrective actions taken and, if known, the name and address of the industrial user(s), responsible. Discussions shall also include a review of applicable pollutant limitations to determine whether any additional limitations or changes to existing requirements may be necessary to prevent pass-through, interference, or noncompliance with sludge disposal requirements. 9.2.3. The cumulative number of industrial users that the Discharger has notified regarding Baseline Monitoring Reports and the cumulative number of industrial user responses. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-27 9.2.4. An updated list of the Discharger's industrial users, including their names and addresses, or a list of deletions and additions keyed to a previously submitted list. The Discharger shall provide a brief explanation for each deletion. The list shall identify the industrial users subject to Federal Categorical Standards by specifying which set(s) of standards are applicable. The list shall indicate which categorical industries, or specific pollutants from each industry, are subject to local limitations that are more stringent than the Federal Categorical Standards. The Discharger shall also list the non-categorical industrial users that are subject only to local discharge limitations. The Discharger shall characterize the compliance status of each industrial user by employing the following descriptions. 9.2.4.1. In compliance with Baseline Monitoring Report requirements (where applicable); 9.2.4.2. Consistently achieving compliance; 9.2.4.3. Inconsistently achieving compliance; 9.2.4.4. Significantly violated applicable pretreatment requirements defined by 40 C.F.R. 403.8 (f)(2)(vii); 9.2.4.5. On a schedule to achieve compliance (include the date final compliance is required); 9.2.4.6. Not achieving compliance and not on a compliance schedule; or 9.2.4.7. The Discharger does not know the industrial user's compliance status. A report describing the compliance status of any industrial user characterized by descriptions in Items 9.2.4.4.3. through 9.2.4.4.7., above, shall be submitted quarterly from the annual report date to the State Water Board, Central Coast Water Board, and U.S. EPA. The report shall identify the specific compliance status of each such industrial user. This quarterly reporting requirement shall commence upon issuance of this Order. Quarterly reports shall be submitted May 1, August 1, and November 1. The fourth quarter report shall be incorporated in the Annual Report (February 1). Quarterly reports shall briefly describe POTW compliance with audit/pretreatment compliance inspection requirements. If none of the aforementioned conditions exist, at a minimum, a letter indicating that all industries are in compliance and no violations or changes to the pretreatment program have occurred during the quarter must be submitted. 9.2.4.8. A summary of inspection and sampling activities conducted by the Discharger during the past year to gather information and data regarding industrial users. The summary shall include the following: 9.2.4.8.1. Names and addresses of the industrial users subject to surveillance by the Discharger and an explanation of whether they were inspected, sampled, or both and the frequency of these activities at each user; and 9.2.4.8.2. Conclusions or results from the inspection or sampling of each industrial user. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-28 9.2.4.9. A summary of compliance and enforcement activities during the past year. The summary shall include names and addresses of the industrial users affected by the following actions. 9.2.4.9.1. Warning letters or notices of violation regarding the industrial users' apparent noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the apparent violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.2. Administrative Orders regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.3. Civil actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.4. Criminal actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned Federal Categorical Standards or local discharge limitations; 9.2.4.9.5. Assessment of monetary penalties. For each industrial user, identify the amount of the penalties; 9.2.4.9.6. Restriction of flow to the POTW; and 9.2.4.9.7. Disconnection from discharge to the POTW. 9.2.4.10. Description of any significant changes in operating the pretreatment program, which differ from the information in the Discharger's approved POTW Pretreatment Program including, but not limited to, changes concerning: 9.2.4.10.1. The program's administrative structure; 9.2.4.10.2. Local industrial discharge limitations; 9.2.4.10.3. Monitoring program and monitoring frequencies; 9.2.4.10.4. Legal authority or enforcement policy; 9.2.4.10.5. Funding mechanisms; 9.2.4.10.6. Resource requirements; and 9.2.4.10.7. Staffing levels. 9.2.4.11. A summary of the annual pretreatment budget, including costs of pretreatment program functions and equipment purchases. 9.2.4.12. A summary of public participation activities to involve and inform the public. 9.2.4.13. A description of any changes in sludge disposal methods and a discussion of any concerns not described elsewhere in the report. The pretreatment quarterly and annual reports shall be signed by a principal executive officer, CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-29 ranking elected official, or other duly authorized employee who is responsible for the overall operation of the Discharger (POTW - 40 C.F.R. section 403.12(m)). The Discharger shall submit signed copies of the reports to the State Water Board and the Regional Water Board electronically through the SMR module of CIWQS. Signed copies of the reports shall also be submitted electronically to U.S. EPA at R9Pretreatment@epa.gov or as instructed otherwise. 9.3. Salt and Nutrient Management Plan Reporting The previous Order required the Discharger to develop and implement an ongoing salts management plan dedicated to minimize the discharge of salts to and attainment of applicable water quality objectives (WQOs) for salts in San Luis Obispo Creek sub- basin of the Estero Bay Drainage Basin. Additionally, the previous order required the Discharger to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable WQOs for nutrients in the same basin. Based on the annual reports supplied by the Discharger, over the previous period of the Order, the Discharger has demonstrated that the effluent has contributed to exceedances of 2019 Basin Plan WQOs for salts. By February 1 of each year, the Discharger shall submit an annual report (separate from the NPDES annual report) describing salt and nutrient reduction efforts. The report shall include, at a minimum: 9.3.1. Salt Component 9.3.1.1. Calculations of annual salt mass discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; 9.3.1.2. Analysis of wastewater evaporation/salt concentration effects; 9.3.1.3. Analysis of groundwater monitoring results for salts constituents and associated trends; 9.3.1.4. Analysis of potential impacts of salt loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.1.5. A summary of existing salt reduction measures; and, 9.3.1.6. Recommendations and time schedules for implementation of any additional salt reduction measures. 9.3.2. Nutrient Component 9.3.2.1. Calculations of annual nitrogen mass (for all identified species) discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; 9.3.2.2. Analysis of wastewater treatment facility ability to facilitate nitrification and denitrification, or other means of nitrogen removal; 9.3.2.3. Analysis of groundwater monitoring results for nitrogen constituents and trends; CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-30 9.3.2.4. Analysis of potential impacts of nitrogen loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.2.5. A summary of existing nitrogen loading reduction measures; and, 9.3.2.6. Recommendations and time schedules for implementation of any additional nitrogen loading reduction measures. 9.4. Volumetric Monitoring of Wastewater and Recycled Water 9.4.1. Monthly volume of wastewater collected and treated by the wastewater treatment plant. 9.4.2. Monthly volume of wastewater treated, specifying level of treatment, including treated wastewater discharged. 9.4.3. Monthly volume of treated wastewater discharged, monthly volume of recycled water distributed for reuse, and annual volume of treated wastewater distributed for beneficial use in compliance with California Code of Regulations, title 22 use categories. 9.5 Discharge to Evaporation Ponds 9.5.1. The Discharger shall provide written notification to the Central Coast Water Board when there is any discharge to or from the Facility’s evaporation ponds, which are described in section 2.1 of the Fact Sheet. If the discharge is anticipated, the Discharger shall provide notice within 10 days prior to the anticipated discharge. If the discharge is unanticipated, the Discharger sh all provide notice within 24 hours of the time the discharge occurs. Discharge from the evaporation ponds is not permitted in this Order, so standard provision 5.5 applies. The notification must include discharge dates, times, volumes, and reasons for discharge. The notification must be submitted electronically, consistent with standard provision 5.10. 10. REPORTING REQUIREMENTS 10.1. General Monitoring and Reporting Requirements The Discharger shall comply with all Standard Provisions (Attachment D) related to monitoring, reporting, and recordkeeping. 10.2. Self-Monitoring Reports (SMRs) 10.2.1. The Discharger shall electronically submit SMRs using the State Water Board’s California Integrated Water Quality System (CIWQS) Program website (http://www.waterboards.ca.gov/water_issues/programs/ciwqs). The CIWQS website will provide additional information for SMR submittal in the event there will be a planned service interruption for electronic submittal. 10.2.2. The Discharger shall report in the SMR the results for all monitoring specified in this MRP under sections 3 through 9. The Discharger shall submit SMRs including the results of all required monitoring using U.S. EPA -approved test CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-31 methods or other test methods specified in this Order. SMRs are to include all new monitoring results obtained since the last SMR was submitted. If the Discharger monitors any pollutant more frequently than required by this Order, the results of this monitoring shall be included in the calculations and reporting of the data submitted in the SMR. 10.2.3. Monitoring periods and reporting for all required monitoring shall be completed according to the following schedule: Table E-10. Monitoring Periods and Reporting Schedule SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date NPDES Monitoring Report – Continuous, Daily, Weekly, Monthly MRP Sections 3 (Influent), 4 (Effluent) and 5 (Whole Effluent Toxicity), 9.5 Monthly First day of second calendar month following period of sampling Updated Toxicity Reduction Evaluation Work Plan Permit Section 6.3.2.1.1 Once 90 days following permit NPDES Monitoring Report - Quarterly MRP Sections 4 (Effluent) and 8.1 (Receiving Water) Quarterly May 1st August 1st November 1st February 1st NPDES Monitoring Report – Annually MRP Sections 4 (Effluent) and 8.1 (Receiving Water), 9.5 Annually February 15th Recycled Water Monitoring Report MRP Section 7.1 (Recycled Water Monitoring) Annually April 1st, the year following Recycled Water Volumetric Monitoring MRP Section 9.4 (Volumetric Reporting of Wastewater and Recycled Water) Annually April 30th, the year following sampling Note: This report is submitted using CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-32 SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date the GeoTracker system, not CIWQS Biosolids Monitoring Report MRP Section 9.1 (Biosolids Monitoring) Annually February 19th, the year following sampling Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Quarterly May 1st August 1st November 1st February 1st Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Annually February 15th, the year following sampling Summary Report Attachment D, Standard Provision, 8.4.8 (page D-16) Annually February 15th, the year following Salt and Nutrient Management Plan Annual Report MRP Section 9.3 (Salt and Nutrient Management Plan Reporting) Annually February 15th, the following year Pollutant Minimization Program Annual Report Permit Section 6.3.3.2 (Pollutant Minimization Program) Annually February 15th, the following year Climate Change Implementation Progress Report Permit Section 6.3.6.2 (Climate Change Adaptation Implementation Progress Report) Every five years May 1st, every five years following permit effective date. ROWD Application Permit renewal application Once per permit term 180 days prior to permit expiration date 10.2.4. Reporting Protocols. The Discharger shall report with each sample result the applicable Reporting Level (RL) and the current Method Detection Limit (MDL), as determined by the procedure in 40 C.F.R. part 136. The Discharger shall report the results of analytical determinations for the presence of chemical constituents in a sample using the following reporting protocols: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-33 10.2.4.1. Sample results greater than or equal to the RL shall be reported as measured by the laboratory (i.e., the measured chemical concentration in the sample). 10.2.4.2. Sample results less than the RL, but greater than or equal to the laboratory’s MDL, shall be reported as “Detected, but Not Quantified,” or DNQ. The estimated chemical concentration of the sample shall also be reported. For the purposes of data collection, the laboratory shall write the estimated chemical concentration next to DNQ. The laboratory may, if such information is available, include numerical estimates of the data quality for the reported result. Numerical estimates of data quality may be percent accuracy (± a percentage of the reported value), numerical ranges (low to high), or any other means considered appropriate by the laboratory. 10.2.4.3. Sample results less than the laboratory’s MDL shall be reported as “Not Detected,” or ND. 10.2.4.4. Dischargers are to instruct laboratories to establish calibration standards so that the ML value (or its equivalent if there is differential treatment of samples relative to calibration standards) is the lowest calibration standard. At no time is the Discharger to use analytical data derived from extrapolation beyond the lowest point of the calibration curve. 10.2.5. Compliance Determination. Compliance with effluent limitations for priority pollutants shall be determined using sample reporting protocols defined above and Attachment A. For purposes of reporting and administrative enforcement by the Central Coast Water Board and State Water Board, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the priority pollutant in the monitoring sample is greater than the effluent limitation and greater than or equal to the reporting level (RL). 10.2.6. Multiple Sample Data. When determining compliance with an AMEL, AWEL, or MDEL for priority pollutants and more than one sample result is available, the Discharger shall compute the arithmetic mean unless the data set contains one or more reported determinations of “Detected, but Not Quantified” (DNQ) or “Not Detected” (ND). In those cases, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 10.2.6.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 10.2.6.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 10.2.7. The Discharger shall submit SMRs in accordance with the following requirements: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-34 10.2.7.1. The Discharger shall arrange all reported data in a tabular format. The data shall be summarized to clearly illustrate whether the facility is operating in compliance with interim and/or final effluent limitations. The Discharger is not required to duplicate the submittal of data that is entered in a tabular format within CIWQS. When electronic submittal of data is required and CIWQS does not provide for entry into a tabular format within the system, the Discharger shall electronically submit the data in a tabular format as an attachment. 10.2.7.2. The Discharger shall attach a cover letter to the SMR. The information contained in the cover letter shall clearly identify violations of the waste discharge requirements; discuss corrective actions taken or planned; and the proposed time schedule for corrective actions. Identified violations must include a description of the requirement that was violated and a description of the violation. 10.2.7.3. The Discharger shall electronically self-report all violations of the waste- discharge requirements using the CIWQS self-reported violations function. 10.3. Discharge Monitoring Reports (DMRs) 10.3.1. DMRs are U.S. EPA reporting requirements. The Discharger shall electronically certify and submit DMRs together with SMRs using Electronic Self-Monitoring Reports module eSMR 2.5 or any upgraded version. Electronic DMR submittal shall be in addition to electronic SMR submittal. Information about electronic DMR submittal is available at the DMR website at: (http://www.waterboards.ca.gov/water_issues/programs/discharge_monitoring). 10.4. Other Reports 10.4.1. The Discharger shall report the results of any special studies, acute and chronic toxicity testing, TRE/TIE, and PMP, required by Special Provisions – 6.3. The Discharger shall report the progress in satisfaction of compliance schedule dates specified in Special Provisions – 6.3.7. The Discharger shall submit reports with the first monthly SMR scheduled to be submitted on or immediately following the report due date. 10.4.2. The Discharger shall report the volumetric monitoring requirements as specified in Other Monitoring Requirements - 9.4 to the State Water Board by April 30 of each calendar year. The Discharger shall electronically certify and submit this annual report containing the required data via the State Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. Information about the volumetric reporting of wastewater and recycled water and the Recycled Water Policy is available at the Recycled Water Policy Volumetric Annual Reporting website at http://www.waterboards.ca.gov/recycledwaterpolicy. 10.4.3. Every five years, the Discharger shall submit a Climate Change Implementation Progress Report as specified in section 6.3.6.2 of this Order. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-1 F. ATTACHMENT F – FACT SHEET TABLE OF CONTENTS 1. PERMIT INFORMATION .......................................................................................... F-3 2. FACILITY DESCRIPTION ........................................................................................ F-5 2.1. Description of Wastewater and Biosolids Treatment and Controls ........................ F-5 2.2. Discharge Points and Receiving Waters ............................................................... F-6 2.3. Summary of Existing Requirements and Self Monitoring Report Data .................. F-6 2.4. Summary of Interim Effluent Limits and Time Schedule Orders ............................ F-8 2.5. Compliance Summary ........................................................................................... F-9 2.6. Planned Changes ................................................................................................ F-10 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS ...................................... F-10 3.1. Legal Authorities.................................................................................................. F-11 3.2. California Environmental Quality Act (CEQA) ..................................................... F-11 3.3. State and Federal Laws, Regulations, Policies, and Plans ................................. F-11 3.4. Impaired Waterbodies on the CWA section 303(d) List ....................................... F-15 3.5. Other Plans, Polices and Regulations ................................................................. F-15 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS ................................................................................................................................... F-17 4.1. Discharge Prohibitions ........................................................................................ F-17 4.2. Technology-Based Effluent Limitations ............................................................... F-18 4.3. Water Quality-Based Effluent Limitations (WQBELs) .......................................... F-20 4.4. Final Effluent Limitation Considerations .............................................................. F-42 4.5. Interim Effluent Limitations – Not Applicable ....................................................... F-47 4.6. Land Discharge Specifications – Not Applicable ................................................. F-47 4.7. Recycling Specifications ...................................................................................... F-47 4.8. Point of Compliance for Effluent Limitations ........................................................ F-47 5. RATIONALE FOR RECEIVING WATER LIMITATIONS ........................................ F-48 5.1. Surface Water ..................................................................................................... F-48 6. RATIONALE FOR PROVISIONS ........................................................................... F-48 6.1. Standard Provisions ............................................................................................ F-48 6.2. Special Provisions ............................................................................................... F-48 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS .............. F-52 7.1. Influent Monitoring ............................................................................................... F-53 7.2. Effluent Monitoring .............................................................................................. F-53 7.3. Whole Effluent Toxicity Testing Requirements .................................................... F-53 7.4. Recycled Water Monitoring ................................................................................. F-54 7.5. Receiving Water Monitoring ................................................................................ F-54 7.6. Other Monitoring Requirements .......................................................................... F-55 9. PUBLIC PARTICIPATION ...................................................................................... F-58 9.1. Notification of Interested Persons........................................................................ F-58 9.2. Written Comments ............................................................................................... F-59 9.4. Reconsideration of Waste Discharge Requirements ........................................... F-59 9.5. Information and Copying ..................................................................................... F-59 9.6. Register of Interested Persons ............................................................................ F-60 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-2 9.7. Additional Information .......................................................................................... F-60 TABLE OF TABLES Table F-1. Facility Information ...................................................................................... F-3 Table F-2. Historic Effluent Limitations and Monitoring Data ........................................ F-7 Table F-3. TSO R3-2014-0036 Interim Effluent Limits ................................................. F-9 Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 ...... F-9 Table F-5. Basin Plan Beneficial Uses ....................................................................... F-12 Table F-6. Secondary Treatment Requirements ........................................................ F-19 Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 ................. F-19 Table F-8. Summary of RPA Results ......................................................................... F-23 Table F-9. Summary of Acute and Chronic Toxicity Test Results .............................. F-39 Table F-10. Final Effluent Limitations – Discharge Point EFF-001 ............................. F-44 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-3 ATTACHMENT F – FACT SHEET As described in section 2.2 of this Order, the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) incorporates this Fact Sheet as findings of the Central Coast Water Board supporting the issuance of this Order. This Fact Sheet includes the legal requirements and technical rationale that serve as the basis for the requirements of this Order. This Order has been prepared under a standardized format to accommodate a broad range of discharge requirements for dischargers in California. Only those sections or subsections of this Order that are specifically identified as “not applicable” have been determined not to apply to this Discharger. Sections or subsections of this Order not specifically identified as “not applicable” are applicable to this Discharger. 1. PERMIT INFORMATION The following table summarizes administrative information related to the facility. Table F-1. Facility Information WDID 3 400107001 Discharger City of San Luis Obispo Name of Facility City of San Luis Obispo Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Facility Contact, Title and Phone Patrick McGrath, WRRF Supervisor 805-781-7240 Authorized Person to Sign and Submit Reports Patrick McGrath, WRRF Supervisor 805-781-7240 Mailing Address 35 Prado Road, San Luis Obispo, CA 93401 Billing Address 35 Prado Road, San Luis Obispo, CA 93401 Type of Facility Publicly Owned Treatment Works (POTW) Major or Minor Facility Major Threat to Water Quality 2 Complexity A Pretreatment Program Yes CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-4 Recycling Requirements Production: NPDES R3-2024-0001 Distribution and Use: WQ 2016-0068, DDW Water Reclamation Requirements for Recycled Water Facility Permitted Flow 5.4 million gallons per day (MGD) Facility Design Flow 5.4 MGD Watershed Estero Bay Hydrologic Unit Receiving Water San Luis Obispo Creek Receiving Water Type Inland surface water 1.1. The City of San Luis Obispo (hereinafter Discharger or the City) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (hereinafter Facility), a publicly owned treatment works (POTW). For the purposes of this Order, references to the “discharger” or “permittee” in applicable federal and state laws, regulations, plans, or policy are held to be equivalent to references to the Discharger herein. 1.2. The Facility discharges wastewater to San Luis Obispo Creek, a water of the United States. 1.3. When applicable, state law requires dischargers to file a petition with the State Water Resources Control Board (State Water Board), Division of Water Rights and receive approval for any change in the point of discharge, place of use, or purpose of use of treated wastewater that decreases the flow in any portion of a watercourse. The State Water Board retains separate jurisdictional a uthority to enforce any applicable requirements under California Water Code section 1211. This is not an NPDES permit requirement. 1.4. The Discharger was previously regulated by Order R3-2014-0033 and National Pollutant Discharge Elimination System (NPDES) Permit CA0049224 adopted on September 25, 2014, and effective on December 1, 2014. The Discharger was also regulated by Time Schedule Order R3-2014-0036 and Time Schedule Order R3- 2019-0124. The Discharger filed a Report of Waste Discharge (ROWD) and submitted an application for reissuance of its waste discharge requirements (WDRs) and NPDES permit on May 28, 2019. 1.5. The Discharger was previously regulated by Waste Discharge Requirements and Master Reclamation Requirements Order R3-2003-081, which authorized the production, distribution, and use of recycled water. 1.6. Federal regulations at 40 C.F.R. section 122.46 limit the duration of NPDES permits to a fixed term not to exceed five years. However, pursuant to California Code of Regulations, title 23, section 2235.4, the terms and conditions of an expired permit are automatically continued pending reissuance of the permit if the Discharger complies with all federal NPDES requirements for continuation of expired permits. Because the Discharger met the requirements of California Code of Regulations, title 23, section 2235.4, Order No. R3-2014-0033, NPDES Permit No. CA0049224 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-5 was administratively continued after the original expiration date of November 30, 2019. 2. FACILITY DESCRIPTION 2.1. Description of Wastewater and Biosolids Treatment and Controls The City of San Luis Obispo Resource Recovery Facility is a municipal wastewater collection, treatment, and disposal facility that discharges tertiary treated wastewater to San Luis Obispo Creek. First constructed in 1920 and located at the southwest corner of the City of San Luis Obispo and adjacent to San Luis Obispo Creek, the Facility provides sewerage service to approximately 47,328 municipal and industrial users from the City of San Luis Obispo, California Polytechnic State University, San Luis Obispo, and the San Luis Obispo County Regional Airport. The City also administers an approved pretreatment program that includes seven significant industrial users, as defined in federal regulations. The Discharger currently operates a collection system that is composed of over 148 miles of main line and 9 lift stations. The design flow capacity of the Facility is 5.4 MGD. During storm events, the estimated wet weather influent flow to the facility is 11.1 MGD due to inflow and infiltration into the collection system from aging or broken/cracked pipes. Ongoing capital improvement projects for sewer line replacement, flow metering, and main line repairs will continue to address areas of concern that result in inflow and infiltration into the Facility. The Discharger has been implementing a significant upgrade of the Facility’s biological, disinfection, and biosolids units since 2019. A focus of the facility upgrade was to improve removal of chorine disinfection byproducts (trihalomethanes, or THMs) and nitrate to meet effluent limits of the previous permit. Another focus of the upgrade was to increase the facility’s ability to treat high inflows from wet-weather events. Prior to the most recent upgrades, the facility’s treatment process consisted of an equalization basin, mechanical screening, grit removal, primary settling, biofiltration, secondary settling, nitrification with two activated sludge aeration basins, final settling, cooling using evaporative cooling towers, dual media filtration, and chlorination/dechlorination. During the upgrade, the discharger removed or abandoned the following components of the facility: bio filter and secondary clarifier, final clarifiers, tertiary dual media filtration, and chlorine disinfection and dechlorination. The two activated sludge basins were converted to Modified Ludzack-Ettinger (MLE) bioreactors for nutrient removal, the dissolved air floatation thickener (DAFT) was modified into a sludge blend tank, and a digester was modified into an odor control unit. The final upgraded treatment system currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four MLE bioreactors, hollowfiber membranes, and UV disinfection. Although chlorination and dechlorination of the effluent and recycled water has been terminated due to the use of UV disinfection, the recycled water sent to the storage tank will be dosed with chlorine to maintain a chlorine residual in the recycled water distribution line per best practices of the distribution system. The Discharger may use sodium hypochlorite (chlorine) for CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-6 maintenance purposes such as membrane cleaning in the MLE unit when hydrogen peroxide and/or citric acid is insufficient. If chlorine is used for membrane cleaning, dechlorination of the effluent with sodium bisulfite may be necessary remove the chlorine residual to protect beneficial uses of San Luis Obispo Creek. Biosolids were previously handled with a dissolved air floatation thickener (DAFT), three anaerobic digesters, a screw press, a belt filter press, and drying beds, with the final product shipped out for composting. The upgraded biosolids handling train now consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, a digested sludge storage tank, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. There are two lined evaporation ponds located at southwest corner of the Facility property. The Discharger has occasionally diverted wastewater to these ponds when it did not meet effluent limitations, rather than discharging the wastewater to the creek. This Order requires the Discharger to submit a written notification to the Central Coast Water Board when wastewater is sent to these ponds. This Order does not provide regulatory coverage for the discharge of wastewater from these ponds to land or surface water. In recent years with large, prolonged storm events, these ponds have filled with stormwater from overland flow (not from the facility). This Order does not provide coverage of stormwater discharge from these ponds. As discussed further in section 3.5.1 of this Fact Sheet, the Discharger is enrolled in the Industrial General Permit (State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001). The Discharger may incorporate these ponds into their Industrial General Permit enrollment to allow for the discharge of stormwater from the ponds, in compliance with all the requirements of the Industrial General Permit. 2.2. Discharge Points and Receiving Waters Tertiary treated wastewater is discharged from Discharge Point EFF-001 to San Luis Obispo Creek, a water of the United States, at latitude 35.244307° N and longitude 120.680618° W. Sampling location EFF-001A is located prior to discharge into the effluent pipeline that discharges to San Luis Obispo Creek. Sampling location EFF-001B is located at the most downstream end of the effluent pipeline that discharges to San Luis Obispo creek. The flowrate in San Luis Obispo Creek varies greatly between the wet and dry seasons. No dilution credit has been granted for this discharge. Tertiary treated wastewater is discharged from Discharge Point EFF-002 to the Discharger’s reclaimed water storage tank that is located just south of the UV disinfection system. The reclaimed water storage tank feeds the Discharger’s reclaimed water distribution lines located throughout the city. 2.3. Summary of Existing Requirements and Self Monitoring Report Data Effluent limitations contained in Order R3-2014-0033 for discharges from Discharge Point 001 (Monitoring Location EFF-001) and representative monitoring data from December 1, 2014, to December 1, 2022, are shown in Table F-2: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-7 Table F-2. Historic Effluent Limitations and Monitoring Data Parameter Units Averag e Monthl y Effluen t Limit Averag e Weekly Effluen t Limit Maximum Daily Effluent Limit Highest Average Monthly Discharge Reported Highest Average Weekly Discharge Reported Highest Daily Discharge Reported Flow (dry weather) MGD 5.1 --- --- 8.0 --- 12.9[1] Biochemical Oxygen Demand 5- day @ 20°C (BOD5) milligra ms per liter (mg/L) 10 30 50 8.84 14.3 12.6 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) pounds per day (lbs/day ) 425 1275 2125 382 382 382 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) percent removal ≥85 --- --- 91.6 – 100[2] Total Suspended Solids (TSS) mg/L 10 30 75 7.9 11 23.3 Total Suspended Solids (TSS) lbs/day 425 1275 3190 572 842 1556 Total Suspended Solids (TSS) percent removal ≥85 --- --- 97.3-99.7[2] --- --- Oil and Grease mg/L 5 --- 10 8 --- 8 Settleable Solids milliliter per liter per hour (mL/L/h r) 0.1 --- --- <0.1 --- --- pH standar d units 6.5– 8.3[3] 6.5 – 7.88[4] Nitrate, Total (as N) mg/L 10 --- --- 51.7 --- --- Chlorodibro momethane µg/L 0.4 --- 1.0 5 --- 5 Dichlorobro momethane µg/L 0.56 --- 1.0 22 --- 22 N- Nitrosodimet hylamine µg/L 0.0006 9 --- 0.0014 ND --- ND Dissolved Oxygen mg/L 4.0[5] 4.8 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-8 Chlorine Residual mg/L --- --- ND[6] --- --- 0.76 Chronic Toxicity Toxic Units Chronic (TUc) --- --- 1.0 --- --- 4.0 Fecal or Total Coliform Bacteria Most probabl e number (MPN)/ 100 mL [7] [8] [9] 79, 94[10] 1.8 350 [1] Reported as maximum daily. Flow occurred in February 2017 during a wet weather event. [2] The numbers represent the range of lowest to highest reported values. [3] Applied as an instantaneous minimum and maximum effluent limitation. [4] Representative values contain the lowest instantaneous minimum to the highest instantaneous maximum. [5] Applied as an instantaneous minimum effluent limitation. [6] ND = less than 0.1 mg/L. Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [7] No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 -day period. [8] The median number of fecal coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days for which analyses have been completed. [9] The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [10] Values occurred within a 30-day time period. 2.4. Summary of Interim Effluent Limits and Time Schedule Orders During the permit term for Order R3-2014-0036, the discharger could not immediately achieve compliance with the chlorodibromomethane, dichlorobromomethane, and nitrate effluent limitations. The Central Coast Water Board issued two time schedule orders (TSOs) to set interim effluent limits and compliance timelines: TSO R3-2014- 0036 and TSO R3-2019-0124. TSO R3-2014-0036 set interim limits for the three aforementioned effluent limits with full compliance with effluent limits by November 30, 2019. With the planned upgrades to the Facility’s biological and disinfection units, TSO R3-2019-0124 extended the deadlines to meet the interim effluent limits with a compliance deadline of March 31, 2020, for chlorodibromomethane and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-9 dichlorobromomethane and a compliance deadline of July 31, 2023 for nitrate. Table F- 3 summarizes the interim effluent limits that were established. The interim effluent limitations were established based on the Facility’s performance. When operating under a TSO, if effluent concentrations exceed the final effluent limitation but do not exceed the interim effluent limitation, an effluent violation has not occurred, and mandatory minimum penalties do not apply. If effluent concentrations exceed both the final and interim effluent limitation values, then an effluent violation has occurred, and mandatory minimum penalties do apply. Table F-3. TSO R3-2014-0036 Interim Effluent Limits Constituent Units Average Monthly Maximum Daily Chlorodibromomethane µg/L - 42 Dichlorobromomethane µg/L - 36 Nitrate (as Nitrogen) mg/L 42.6 - 2.5. Compliance Summary 2.5.1 Effluent Compliance Summary The following discussion is a summary of the violations that occurred during the term and administrative extension of Order No. R3-2014-0033. During the time period from December 1, 2014, to May 31, 2023, the Discharger incurred effluent violations related to nitrate, oil and grease, total coliform, chlorine residual, dichlorobromomethane, and chlorodibromomethane. The number of violations, violation type, and reported value range are provided in Table F-4. Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Nitrate (Total as N) December 2016- November 2022 Monthly Average (Mean) Limit 9 43.2-51.7 10 mg/L Oil and Grease March 2017 Monthly Average Limit 1 6 5 mg/L CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-10 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Total Coliform July 2018- October 2020 30-Day Specific Limit 3 33-1600 23 MPN/ 100m L Total Coliform December 2019- October 2020 Daily Maximum 3 540-1600 240 MPN/ 100m L Residual Chlorine February 2020- December 2022 Daily Maximum 2 0.35-0.75 ND mg/L Dichlorobro momethane April 2020- October 2022 Monthly Average Limit 4 2.5-17.8 0.56 µg/L Dichlorobro momethane April 2020- October 2022 Daily Maximum 4 2.5-17.8 1 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Monthly Average Limit 3 1.2-5 0.40 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Daily Maximum 3 1.2-5 1 µg/L 2.6. Planned Changes The Discharger will continue to implement planned upgrades through 2024. The Discharger has not indicated it plans any significant changes to the Facility beyond those during the term of the Order. 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS The requirements contained in this Order are based on the requirements and authorities described in this section. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-11 3.1. Legal Authorities This Order serves as WDRs pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA), implementing regulations promulgated by the U.S. Environmental Protection Agency (U.S. EPA), and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as an NPDES permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1, subject to the WDRs in this Order. 3.2. California Environmental Quality Act (CEQA) Under California Water Code section 13389, this action to adopt an NPDES permit for an existing facility is exempt from the California Environmental Quality Act (CEQA) provisions in Public Resources Code, division 13, chapter 3 (commencing with section 21100). With respect to the recycling specifications and groundwater limitations, this action is exempt from the provisions of CEQA pursuant to title 14, California Code of Regulations, section 15301, class 1 exemption for permitting of existing facilities with no expansion of existing use. 3.3. State and Federal Laws, Regulations, Policies, and Plans 3.3.1. Water Quality Control Plan. The Central Coast Water Board adopted the Water Quality Control Plan for the Central Coastal Basin (Basin Plan), which designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for all waters addressed through the plan. Requirements in this Order implement the Basin Plan. In addition, the Basin Plan implements State Water Board Resolution 88 -63, which established state policy that all waters, with certain exceptions, should be considered suitable or potentially suitable for municipal or domestic supply. Beneficial uses established by the 2019 Basin Plan for San Luis Obispo Creek (below W. Marsh Street) are presented below: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-12 Table F-5. Basin Plan Beneficial Uses Discharge Point Receiving Water Name Beneficial Use(s) 001 San Luis Obispo Creek (below W. Marsh Street) Existing: Municipal and Domestic Supply (MUN); Agricultural Supply (AGR); Ground Water Recharge (GWR); Water Contact Recreation (REC-1); Non-Contact Water Recreation (REC-2); Wildlife Habitat (WILD); Cold Freshwater Habitat (COLD); Warm Freshwater Habitat (WARM); Migration of Aquatic Organisms (MIGR) Spawning, Reproduction, and/or Early Development (SPWN); Fresh Water Replenishment (FRSH) Commercial and Sport Fishing (COMM). Intermittent: None. Potential: None. Groundwater throughout the Central Coast Region has designated beneficial uses of agricultural water supply, municipal and domestic water supply, and industrial use. Requirements of this Order implement the Basin Plan. 3.3.2. Thermal Plan. The State Water Board adopted the Water Quality Control Plan for Control of Temperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of California (Thermal Plan) January 7, 1971, and amended the plan on September 18, 1975. This plan contains temperature objectives for surface waters. Requirements of this Order implement the Thermal Plan. 3.3.3. Sediment Quality. The State Water Board adopted the Water Quality Control Plan for Enclosed Bays and Estuaries – Part 1, Sediment Quality on September 16, 2008, and it became effective on August 25, 2009. This plan supersedes other narrative sediment quality objectives and establishes new sediment quality objectives and related implementation provisions for specifically defined sediments in most bays and estuaries. Requirements of this Order implement sediment quality objectives of this plan. 3.3.4. National Toxics Rule (NTR) and California Toxics Rule (CTR). U.S. EPA adopted the NTR on December 22, 1992, and later amended it on May 4, 1995 , and November 9, 1999. About forty criteria in the NTR apply in California. On May 18, 2000, U.S. EPA adopted the CTR. The CTR promulgated new toxics criteria for California and, in addition, incorporated the previously adopted NTR criteria CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-13 that were applicable in the state. The CTR was amended on February 13, 2001. These rules contain federal water quality criteria for priority pollutants. 3.3.5. State Implementation Policy. On March 2, 2000, the State Water Board adopted Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (State Implementation Policy or SIP). The SIP became effective on April 28, 2000, with respect to the priority pollutant criteria promulgated for California by the U.S. EPA through the NTR and to the priority pollutant objectives established by the Central Coast Water Board in the Basin Plan. The SIP became effective on May 18, 2000, with respect to the priority pollutant criteria promulgated by the U.S. EPA through the CTR. The State Water Board adopted amendments to the SIP on February 24, 2005, that became effective on July 13, 2005. 3.3.6 Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (ISWEBE Plan). The ISWEBE Plan includes several parts and sections that have been adopted by the State Water Board over time. The applicable parts and sections are discussed below. On May 2, 2017, the State Water Board adopted and ISWEBE Plan Part 2: Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. With ISWEBE Plan Part 2’s approval, the State Water Board approved one new narrative and four new numeric mercury water quality objectives to apply to those inland surface waters, enclosed bays, and estuaries of the state that have any of the following beneficial use designations: COMM, CUL, T-SUB, WILD, MAR, RARE, WARM, COLD, EST, or SAL. The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On August 7, 2018, the State Water Board adopted ISWEBE Plan Part 3: Bacteria Provisions and a Water Quality Standards Variance Policy, which establishes water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On December 1, 2020, the State Water Board adopted the Aquatic Toxicity Provisions, which are incorporated into the ISWEBE Plan. On October 5, 2021, the State Water Board adopted a resolution to confirm that the Aquatic Toxicity Provisions were adopted as state policy for water quality control for all inland surface waters, enclosed bays, estuaries, and coastal lagoons of the state. The provisions were approved by the California Office of Administrative Law on April 25, 2022 and were approved by the U.S. EPA on May 1, 2023. The provisions include statewide numeric water quality objectives for both acute and chronic toxicity and a program of implementation to control toxicity. The provisions provide consistent protection of aquatic life beneficial uses in inland surface waters, enclosed bays, estuaries, and coastal lagoons throughout the state from the effects of known and unknown toxicants. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-14 This Order is consistent with the ISWEBE Plan and includes effluent limitations for mercury, bacteria, and chronic toxicity. 3.3.6. Domestic Water Quality. In compliance with California Water Code section 106.3, it is the policy of the State of California that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. This Order promotes that policy by requiring discharges to meet water quality objectives established in the Basin Plan that are based on drinking water maximum contaminant levels and designed to protect human health and ensure that water is safe for domestic use. 3.3.7. Antidegradation Policy. Federal regulation 40 C.F.R. section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal policy. The State Water Board established California’s antidegradation policy in State Water Board Resolution 68-16, Statement of Policy with Respect to Maintaining High Quality of Waters in California . Resolution 68-16 is deemed to incorporate the federal antidegradation policy where the federal policy applies under federal law. Resolution 68-16 requires that existing water quality be maintained unless degradation is justified by specific findings. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The permitted discharge must be consistent with the antidegradation provision of 40 C.F.R. section 131.12 and State Water Board Resolution 68-16. 3.3.8. Anti-Backsliding Requirements. Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. section 122.44(l) restrict backsliding in NPDES permits. These anti-backsliding provisions require that effluent limitations in a reissued permit must be as stringent as those in the previous permit, with some exceptions in which limitations may be relaxed. 3.3.9. Endangered Species Act Requirements. This Order does not authorize any act that results in the taking of a threatened or endangered species or any act that is now prohibited, or becomes prohibited in the future, under either the California Endangered Species Act (Fish and Game Code sections 2050 to 2097) or the Federal Endangered Species Act (16 U.S.C. sections 1531 to 1544). This Order requires compliance with effluent limits, receiving water limits, and other requirements to protect the beneficial uses of waters of the state. The Discharger is responsible for meeting all applicable requirements of the endangered species acts. 3.3.10. Sewage Sludge and Biosolids. This Order does not authorize any act that results in violation of requirements administered by U.S. EPA to implement 40 C.F.R. part 503, Standards for the Use or Disposal of Sewage Sludge. These standards regulate the final use or disposal of sewage sludge that is generated during the treatment of domestic sewage in a municipal wastewater treatment facility. The Discharger is responsible for meeting all applicable requirements of 40 C.F.R. part 503 that are under U.S. EPA’s enforcement authority. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-15 3.4. Impaired Waterbodies on the CWA section 303(d) List CWA section 303(d) requires states to identify and make a list of specific water bodies where water quality standards are not expected to be met after implementation of technology-based effluent limitations on point sources. For all CWA section 303(d) listed water bodies and pollutants, the Central Coast Water Board must develop and implement total maximum daily loads (TMDLs) that specify waste load allocations (WLAs) for point sources and load allocations (LAs) for non- point sources. The U.S. EPA approved the State’s 2020-2022 303(d) list of impaired water bodies on May 11, 2022. The 2020-2022 303(d) list identifies San Luis Obispo Creek, below Osos Street, as impaired for chloride, sodium, benthic community effects, Escherichia coli (E. coli), dissolved oxygen, nitrate, and toxicity. A TMDL for nitrate was adopted for San Luis Obispo Creek below West Marsh Street. Effluent limitations for nitrate in this Permit are based on Central Coast Water Board Resolution R3-2005-0106 (TMDL for nitrate). A TMDL for pathogens was adopted for San Luis Obispo Creek (R3-2004-0142) but the Facility was not identified as a source and was not assigned a wasteload allocation. However, the Discharger is implementing a Wasteload Allocation Attainment Plan (WAAP) to address pathogens from the sources identified in the TMDL. 3.5. Other Plans, Polices and Regulations 3.5.1. State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001, Waste Discharge Requirements for Stormwater Associated with Industrial Activities Excluding Construction Activities (Industrial General Permit). The Industrial General Permit, adopted April 1, 2014, amended August 4, 2015, and November 6, 2018, and effective July 1, 2015, is applicable to POTWs with a design capacity greater than 1.0 MGD. The purpose of the Industrial General Order is to regulate stormwater discharges associated with industrial activities. For the control of stormwater discharged from the Facility, the Discharger has enrolled in and is regulated by the Industrial General Permit. 3.5.2. State Water Board Order. 2022-0103-DWQ Statewide General Waste Discharge Requirements for Sanitary Sewer Systems. State Water Board Order No. 2022-0103-DWQ, adopted on December 6, 2022, is applicable to all "federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California." The purpose of Water Quality Order 2022-0103-DWQ is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled in Water Quality Order 2022-0103-DWQ and must comply with its requirements and any requirements in reissuances to Water Quality Order 2022-0103-DWQ. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-16 3.5.3. State Water Board Recycled Water Policy. The State Water Board adopted the Quality Control Policy for Recycled Water (Recycled Water Policy) on December 11, 2018, and it became effective on April 8, 2019. The purpose of the Recycled Water Policy is to encourage the safe use of recycled water in a manner that is protective of public health and the environment. This Order implements the Recycled Water Policy by supporting the production of recycled water and requiring volumetric reporting of wastewater and recycled water to the State Water Board. The Recycled Water Policy calls for the development of regional groundwater basin/sub-basin salt/nutrient management plans. This Order requires the Discharger to continue to commit funding and in-kind resources to facilitate development of a regional groundwater basin/sub-basin salt/nutrient management plan that implements the Recycled Water Policy. 3.5.4 Statewide General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW). State Water Board Order WQ 2016-0068-DDW, adopted on June 7, 2016, is applicable to recycled water projects where recycled water is used or transported for non -potable uses. The distribution and offsite reuse of recycled water produced by the Facility is subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. 3.5.5 Environmental Justice and Advancing Racial Equity. When issuing or reissuing individual waste discharge requirements or waivers of waste discharge requirements that regulate an activity or a facility that may impact a disadvantaged or tribal community, and that includes a time schedule in accordance with subdivision (c) of Section 13263 for achieving an applicable water quality objective, an alternative compliance path that allows time to come into compliance with water quality objectives, or a water quality variance, the Central Coast Water Board shall make a finding on potential environmental justice, tribal impact, and racial equity considerations. (Water Code § 13149.2, effective Jan. 1, 2023). Water Code section 189.7 requires the Central Coast Water Board to conduct outreach in disadvantaged and/or tribal communities when adopting individual waste discharge requirements. In accordance with the Water Boards’ efforts to advance racial equity, the Central Coast Water Board is also committed to developing and implementing policies and programs to advance racial equity and environmental justice so that race can no longer be used to predict life outcomes, and outcomes for all groups are improved. Upon review of readily available information, the Central Coast Water Board finds that this Order regulates a discharge that does not disproportionately impact the water quality of an economically disadvantaged community or a tribal community. Similarly, this Order does not include a time schedule, alternative compliance path, or variance. Therefore, Water Code section 13149.2 does not apply to this permit reissuance. Nevertheless, the Central Coast Water Board has conducted outreach consistent with Water Code section 189.7 by reaching out to surrounding communities and tribal communities about this Order. Additionally, the Board has considered any environmental justice concerns within the Board’s authority, in accordance with the Water Boards’ efforts to advance racial equity. The Order CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-17 requires the Permittee to meet water quality standards to protect public health and the environment, thereby benefiting all persons and communities within the Region. 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS The CWA requires point source dischargers to control the amount of conventional, non-conventional, and toxic pollutants that are discharged into the waters of the United States. The control of pollutants discharged is established through effluent limitations and other requirements in NPDES permits. There are two principal bases for effluent limitations in the Code of Federal Regulations: 40 C.F.R. section 122.44(a) requires that permits include applicable technology-based limitations and standards, and 40 C.F.R. section 122.44(d) requires that permits include water quality-based effluent limitations to attain and maintain applicable numeric and narrative water quality criteria to protect the beneficial uses of receiving waters. When numeric water quality objectives have not been established, but a discharge has the reasonable potential to cause or contribute to exceedances of water quality standards described at 40 C.F.R. section 122.44 (d), then 1) water quality based effluent limitations (WQBELS) may be established using a calculated water quality criterion derived from a proposed state criterion or an explicit State policy or regulation interpreting its narrative criterion, 2) WQBELs may be established on a case-by-case basis using U.S. EPA criteria guidance published under CWA Section 304 (a), or 3) WQBELs may be established using an indicator parameter for the pollutant of concern. Several specific factors affecting the development of limitations and requirements in this Order are discussed below. 4.1. Discharge Prohibitions 4.1.1. Discharge Prohibition 3.1. (No discharge at a location or in a manner except as described by the Order). The Order authorizes a single, specific point of discharge to surface waters, and the limitations and conditions established by the Order are based on specific information provided by the Discharger and gained by the Central Coast Water Board through site visits, review of monitoring reports, and other information. Discharges to surface waters at locations not contemplated by this Order or discharges of a character not contemplated by this Order are therefore viewed as inconsistent with CWA section 402’s prohibition against discharges of pollutants except in compliance with the CWA’s permit requirements, effluent limitations, and other enumerated provisions. This prohibition is retained from the previous permit. 4.1.2. Discharge Prohibition 3.2. (Discharge of any waste not specifically regulated by this Order is prohibited). Because limitations and conditions of the Order are based on specific information provided by the Discharger and specific wastes described by the Discharger, the limitations and conditions of the Order do not adequately address waste streams not contemplated during drafting of the Order. To prevent the discharge of such waste streams that may be inadequately CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-18 regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.1.3. Discharge Prohibition 3.3. (Overflow, bypass, or overspray of wastewater from the Discharger’s facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7. (Bypass), is prohibited). The discharge of untreated or partially treated wastewater from the Discharger’s collection, treatment, or disposal facilities represents an unauthorized bypass pursuant to 40 C.F.R. section 122.41(m) or an unauthorized discharge that poses a threat to human health and/or aquatic life, and, therefore, is explicitly prohibited by this Order. 4.1.4. Discharge Prohibition 3.4. (Creation of a condition of pollution, contamination, or nuisance, as defined by Section 13050 of the California Water Code, is prohibited). The Basin Plan requires that the disposal of wastewater to waterbodies be accomplished in a manner that safeguards public health and prevents nuisance conditions. 4.1.5. Discharge Prohibition 3.5. (Discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat). This prohibition is consistent with the requirements of the Basin Plan. 4.1.6. Discharge Prohibition 3.6. (Discharge of radioactive substances is prohibited). This prohibition is consistent with the requirements of the Basin Plan. 4.1.7. Discharge Prohibition 3.7. (Monthly average dry weather effluent flow shall not exceed 5.4 million gallons per day (MGD), aggregated at Discharge Point 001). To prevent the discharge of such waste streams that may be inadequately regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.2. Technology-Based Effluent Limitations 4.2.1. Scope and Authority Section 301(b) of the CWA and implementing U.S. EPA permit regulations at 40 C.F.R. § 122.44 require that permits include conditions meeting applicable technology-based requirements at a minimum, and any more stringent effluent limitations necessary to meet applicable water quality standards. Where the USEPA has not yet developed technology-based standards for a particular industry or a particular pollutant, CWA Section 402 (a) (1) and USEPA regulations at 40 C.F.R. § 125.3 authorize the use of best professional judgment (BPJ) to derive technology-based effluent limitations on a case-by-case basis. When BPJ is used, the permit writer must consider specific factors outlined at 40 C.F.R. § 125.3. Regulations promulgated in 40 C.F.R. § 125.3(a)(1) require technology- based effluent limitations for municipal dischargers to be placed in NPDES permits based on Secondary Treatment Standards or Equivalent to Secondary Treatment Standards. The Federal Water Pollution Control Act Amendments of 1972 (PL 92-500) established the minimum performance requirements for POTWs [defined in section 304(d)(1)]. Section 301(b)(1)(B) of that act requires CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-19 that such treatment works must, as a minimum, meet effluent limitations based on secondary treatment as defined by the U.S. EPA Administrator. Based on this statutory requirement, U.S. EPA developed secondary treatment regulations, which are specified in 40 C.F.R. part 133. These technology-based regulations apply to all municipal wastewater treatment plants and identify the minimum level of effluent quality attainable by secondary treatment in terms of biochemical oxygen demand (BOD5), total suspended solids (TSS), and pH. The discharge authorized by this Order must meet minimum federal technology-based requirements based on Secondary Treatment Standards at 40 C.F.R. part 133 , summarized below: Table F-6. Secondary Treatment Requirements Parameter Units 30-Day Average 7-Day Average BOD5 [1] mg/L 30 45 TSS[1] mg/L 30 45 pH standard units 6.0[2] 9.0[3] [1] The 30-day average percent removal shall not be less than 85 percent. [2] Instantaneous minimum value. [3] Instantaneous maximum value. 4.2.2. Applicable Technology-Based Effluent Limitations 40 C.F.R. section122.45(f)(1) requires effluent limitations be expressed in terms of mass, with some exceptions, and 40 C.F.R. section 122.45(f)(2) allows pollutants that are limited in terms of mass to additionally be limited in terms of other units of measurement. This Order includes effluent limitations expressed in terms of mass and concentration. In addition, pursuant to the exceptio ns to mass limitations provided in 40 C.F.R. section 122.45(f)(1), some effluent limitations are not expressed in terms of mass, such as pH and temperature, as well as when the applicable standards are expressed in terms of concentration and mass limitations are not necessary to protect the beneficial uses of the receiving waters. 4.2.2.1. The following table summarizes technology-based effluent limitations established by this Order at Discharge Point 001. Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 Parameter Units 30-Day Average 7-Day Average Maximum Daily BOD5[1] mg/L 10 30 50 BOD5 lbs/day [2] 450 1,351 2,252 Total Suspended Solids (TSS)[1] mg/L 10 30 75 TSS lbs/day[2] 450 1,351 3,378 [1] The average monthly percent removal of BOD5 and TSS, as measured at Monitoring Location EFF-001, shall not be less than 85 percent. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-20 [2] Mass loading limits were calculated using the following formulas: lbs/day = pollutant concentration (mg/L) * permitted flow (5.4 MGD) * conversion factor (8.34) [3] Instantaneous minimum value. [4] Instantaneous maximum value. 4.2.2.1.1. BOD5 and TSS. BOD and TSS. Federal regulations, 40 C.F.R. part 133, establish the minimum weekly and monthly average level of effluent quality attainable by secondary treatment for BOD5 and TSS. The Central Coast Water Board has determined that tertiary treatment is necessary to protect the beneficial uses of the receiving stream, thus the final effluent limitations for BOD5 and TSS are based on the technical capability of the tertiary process. The secondary and tertiary treatment standards for BOD5 and TSS are indicators of the effectiveness of the treatment processes. The principal design parameter for wastewater treatment plants is the daily BOD5 and TSS loading rates and the corresponding removal rate of the system. In applying 40 C.F.R. part 133 for weekly and monthly average BOD5 and TSS limitations, the application of tertiary treatment processes results in the ability to achieve lower levels for BOD5 and TSS than the secondary standards currently prescribed; the 30 -day average BOD5 and TSS limitations are 10 mg/L, the 7-day average BOD5 and TSS limitations are 30 mg/L. These effluent limitations are based on the capability of a tertiary system. In addition to the average weekly and average monthly effluent limitations, daily maximum effluent limitation of 50 mg/L and 75 mg/L for BOD5 and TSS, respectively, are included in the Order to ensure that the treatment works are not organically overloaded and operate in accordance with design capabilities. In addition, 40 C.F.R. § 133.102, in describing the minimum level of effluent quality attainable by secondary treatment, states that the 30-day average percent removal shall not be less than 85 percent. If 85 percent removal of BOD5 and TSS must be achieved by a secondary treatment plant, it must also be achieved by a tertiary (i.e., treatment beyond secondary level) treatment plant. This Order contains a limitation requiring an average of 85 percent removal of BOD5 and TSS over each calendar month. These effluent limitations are carried over from Order R3-2014-0033. 4.3. Water Quality-Based Effluent Limitations (WQBELs) 4.3.1. Scope and Authority CWA section 301(b) and 40 C.F.R. section 122.44(d) require that permits include limitations more stringent than applicable federal technology -based requirements where necessary to achieve applicable water quality standards. Section 122.44(d)(1)(i) of 40 C.F.R. requires that permits include effluent limitations for all pollutants that are or may be discharged at levels that have the reasonable potential to cause or contribute to an exceedance of a water quality standard, including numeric and narrative objectives within a standard. Where reasonable potential has been established for a pollutant, but there is no numeric criterion or objective for the pollutant, WQBELs must be established using: (1) U.S. EPA criteria guidance under CWA section 304(a), supplemented where CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-21 necessary by other relevant information; (2) an indicator parameter for the pollutant of concern; or (3) a calculated numeric water quality criterion, such as a proposed state criterion or policy interpreting the state’s narrative criterion, supplemented with other relevant information, as provided in section 122.44(d)(1)(vi). The process for determining reasonable potential and calculating WQBELs when necessary is intended to protect the designated uses of the receiving water as specified in the Basin Plan and to achieve applicable water quality objectives and criteria that are contained in other state plans and policies, or any applicable water quality criteria contained in the CTR and NTR. 4.3.2. Applicable Beneficial Uses and Water Quality Criteria and Objectives Beneficial uses described by the 2019 Basin Plan for San Luis Obispo Creek and they are presented in section 3.3.1 of this Fact Sheet. Water quality criteria applicable to this receiving water are established by the CTR, the NTR, and by the 2019 Basin Plan. 4.3.3. Determining the Need for WQBELs NPDES regulations at 40 CFR section 122.44(d) require effluent limitations to control all pollutants which are or may be discharged at a level which will cause, have the reasonable potential to cause, or contribute to an excursion above any State water quality standard. The SIP, the statewide policy that became effective on May 22, 2000, establishes procedures to implement water quality criteria from the NTR and CTR and for priority, toxic pollutant objectives established in the Basin Plan. The implementation procedures of the SIP include methods to determine reasonable potential (for pollutants to cause or contribute to excursions above State water quality standards) and to establish numeric effluent limitations, if necessary, for those pollutants which show reasonable potential. The SIP Section 1.3 requires the Central Coast Water Board to use all available valid, relevant, and representative receiving water and effluent data and information to conduct a reasonable potential analysis (RPA). The Central Coast Water Board analyzed the Discharger’s data for priority pollutants and the nature of the discharge to determine if the discharge has reasonable potential to exceed water quality standards. The RPA is based on effluent data retrieved from CIWQS from the period of December 2014 to December 2022. Some freshwater water quality criteria for metals are hardness dependent, i.e., as hardness decreases, the toxicity of certain metals increases, and the applicable water quality criteria become correspondingly more stringent. The Discharger has not specifically collected hardness data for the receiving water. However, the Central Coast Water Board’s Central Coast Ambient Monitoring Program has nearby monitoring stations on San Luis Obispo Creek that has collected this information. The Water Board used 330 mg/L as CaCO3 as a conservative estimate of the receiving water hardness to determine hardness-based criteria. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-22 To conduct the RPA, the Central Coast Water Board identified the maximum observed effluent (MEC) and background (B) concentrations for each priority, toxic pollutant from receiving water and effluent data provided by the Discharger and compared this data to the most stringent applicable water quality criterion (C) for each pollutant from the NTR, CTR, and the 2019 Basin Plan. The Discharger did not collect background data (B) for receiving water. Section 1.3 of the SIP establishes three triggers for a finding of reasonable potential. 4.3.3.1. Trigger 1. If the MEC is greater than C, there is reasonable potential, and an effluent limitation is required. 4.3.3.2. Trigger 2. If B is greater than C, and the pollutant is detected in effluent (MEC > ND), there is reasonable potential, and an effluent limitation is required. 4.3.3.3. Trigger 3. After reviewing other available and relevant information, a permit writer may decide that a WQBEL is required. Such additional information may include, but is not limited to: the facility type, the discharge type, solids loading analyses, lack of dilution, history of compliance problems, potential toxic impact of the discharge, fish tissue residue data, water quality and beneficial uses of the receiving water, CWA 303(d) listing for the pollutant, and the presence of endangered or threatened species or their critical habitat. For mercury in particular, Part 2 of the SIP revised the above methodology as follows, pursuant to State Water Board Resolution 2017-0027, Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California-Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions (Mercury Provisions). 4.3.3.4. Most stringent water quality objective. The RPA is to use a water column concentration from SIP Part 2’s Table 1 based on the receiving water body type and beneficial use(s) to identify the most stringent mercury water quality objective. For San Luis Obispo Creek, the applicable water column concentration is 0.012 ug/L total mercury. This water column concentration is to be used as the “C” value in the RPA for mercury. This change in methodology changes the water quality objective from 0.05 ug/L in the previous orders to 0.012 ug/L in this Order. 4.3.3.5. Maximum Effluent Concentration. Instead of using the highest observed mercury effluent concentration, the MEC is to be determined as an arithmetic mean of all mercury samples during a calendar year. For this RPA, the highest calendar year arithmetic mean based on the revised methodology for mercury in effluent was 0.03 ug/L. The Discharger collects effluent mercury samples on a yearly basis. 4.3.3.6. Maximum ambient background concentration. Instead of using the highest observed mercury concentration in the upstream receiving water (referred to as “B”), the value of B is to be determined as an arithmetic mean of all mercury samples during a calendar year. This Discharger did not sample for and does not have ambient background concentration data for mercury. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-23 4.3.3.7. Determination. A mercury WQBEL is not required unless the MEC is greater than C. However, if B is greater than C and mercury is detected in the effluent, effluent monitoring is required. A mercury WQBEL is required for this discharge because the MEC (i.e., the highest calendar year average concentration with using one half the mercury detection limits when non -detect) was greater than C and there was no B data available. Therefore, according to Part 2 of the SIP, a mercury effluent limitation is required. Annual monitoring for mercury will be retained from the previous Order. The following table summarizes the RPA for each priority, title 22, or Basin Plan pollutant for which data was available from December 2014 through December 2022 and sets forth the basis upon which WQBELs are included in this Order. Table F-8. Summary of RPA Results CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Priority Pollutants 1 Antimony, Total Recoverable µg/L 9 2.5 6 - No Primary MCL 2 Arsenic, Total Recoverable µg/L 9 <2.0 10 - No Primary MCL 3 Beryllium µg/L 9 <0.2 4 - No Primary MCL 4 Cadmium, Total Recoverable µg/L 9 <0.2 3 - No CA Prim. MCL 5a Chromium (III) µg/L 7 7.0 50 - No CA Prim. MCL for Chromium (Total) 5b Chromium (VI) µg/L 8 1.1 11 - No CTR - Chronic 6 Copper, Total Recoverable µg/L 9 24 26 - No CTR - Chronic 7 Lead, Total Recoverable µg/L 8 6.3 15 - No CA Prim. MCL 8 Mercury, Total Recoverable µg/L 9 0.03 0.012 - Yes Mercury Provisions 9 Nickel, Total Recoverable µg/L 9 7.0 100 - No CA Prim. MCL 10 Selenium, Total Recoverable µg/L 9 1.0 5 - No CTR - Chronic CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-24 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 11 Silver, Total Recoverable µg/L 8 <0.25 31.6 - No CTR - Acute 12 Thallium, Total Recoverable µg/L 9 <0.2 1.7 - No CTR 13 Zinc, Total Recoverable µg/L 9 100 330 - No CTR 14 Cyanide, Total (as CN) µg/L 9 <4.0 5.2 - No CTR 15 Asbestos Million Fibers/L 9 <0.2 7 - No CTR 16 2,3,7,8 TCDD µg/L 9 <0.00000 0251 0.00000001 3 - Ud CTR 17 Acrolein µg/L 8 <5.0 320 - No CTR 18 Acrylonitrile µg/L 8 <2.0 0.059 - Ud CTR 19 Benzene µg/L 9 <0.5 1 - No CA Prim. MCL 20 Bromoform µg/L 73 1.1 4.3 - No CTR 21 Carbon Tetrachloride µg/L 9 <0.5 0.25 - Ud CTR 22 Chlorobenzene µg/L 9 <0.5 70 - No CA Prim. MCL 23 Chlorodibromomethane (aka Dibromochloromethane) µg/L 73 5.4 0.401 - Yes CTR 24 Chloroethane µg/L 8 <0.5 No Criteria - Uc No criteria 25 2-Chloroethylvinyl ether µg/L 8 <1.0 No Criteria - Uc No criteria 26 Chloroform µg/L 8 95.7 60 - Yes NAWQC 27 Dichlorobromomethane µg/L 73 24.8 0.56 - Yes CTR 28 1,1-Dichloroethane µg/L 9 <0.5 5 - No Primary MCL 29 1,2-Dichloroethane µg/L 9 <0.5 0.38 - Ud CTR 30 1,1-Dichloroethylene µg/L 9 <0.5 0.057 - No CTR 31 1,2-Dichloropropane µg/L 9 <0.5 0.52 - No CTR 32 1,3-Dichloropropylene µg/L 1 <0.5 0.5 - No CA Prim. MCL 33 Ethylbenzene µg/L 9 <0.5 300 - No CA Prim. MCL 34 Methyl Bromide (aka Bromomethane) µg/L 8 <0.5 48 - No CTR 35 Methyl Chloride (aka chloromethane) µg/L 8 <0.5 No Criteria - Uc No criteria 36 Methylene Chloride µg/L 9 15 4.7 - Yes CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-25 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 37 1,1,2,2-Tetrachloroethane µg/L 9 <0.5 0.17 - Ud CTR Tetrachloroethylene (aka Tetrachloroethene) µg/L 7 <0.5 0.8 - No CTR 39 Toluene µg/L 9 <0.5 150 - No CA Prim. MCL 40 1,2-Trans-Dichloroethylene µg/L 7 <0.005 10 - No CA Prim. MCL 41 1,1,1-Trichloroethane µg/L 9 <0.5 200 - No CA Prim. MCL 42 1,1,2-Trichloroethane µg/L 9 <0.5 0.6 - No CTR 43 Trichloroethylene (aka Trichloroethene) µg/L 7 <0.5 2.7 - No CTR 44 Vinyl Chloride µg/L 9 <0.5 0.5 - No CA Prim. MCL 45 2-Chlorophenol µg/L 8 <2.0 120 - No CTR 46 2,4-Dichlorophenol µg/L 8 <2.0 93 - No CTR 47 2,4-Dimethylphenol µg/L 8 <1.0 540 - No CTR 48 4,6-dinitro-o-resol (aka 2-methyl-4,6- Dinitrophenol aka 4,6-Dinitro-2- methylphenol) µg/L 7 <1.0 13.4 - No CTR 49 2,4-Dinitrophenol µg/L 8 <5.0 70 - No CTR 50 2-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 51 4-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 52 3-Methyl-4-Chlorophenol (aka P-chloro-m-resol aka 4-Chloro-3- methylphenol) µg/L 8 <1.0 No Criteria - Uc No criteria 53 Pentachlorophenol µg/L 34 2 0.28 - Yes CTR 54 Phenol, Single Compound µg/L 1 <1.0 1 - No BP 55 2,4,6-Trichlorophenol µg/L 8 <1.0 2.1 - No CTR 56 Acenaphthene µg/L 8 <1.0 1200 - No CTR 57 Acenaphthylene µg/L 8 <1.0 No Criteria - Uc No criteria 58 Anthracene µg/L 8 <1.0 9600 - No CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-26 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 59 Benzidine µg/L 8 <1.0 0.00012 - Ud CTR 60 Benzo(a)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 61 Benzo(a)Pyrene µg/L 9 <0.1 0.0044 - Ud CTR 62 Benzo(b)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 63 Benzo(ghi)Perylene µg/L 8 <1.0 No Criteria - Uc No criteria 64 Benzo(k)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 65 Bis(2- Chloroethoxy)Methane µg/L 8 <1.0 No Criteria - Uc No criteria 66 Bis(2-Chloroethyl)Ether µg/L 8 <1.0 0.031 - Ud CTR 67 Bis(2-Chloroisopropyl)Ether µg/L 8 <1.0 1400 - No CTR 68 Bis(2-Ethylhexyl) Phthalate (aka Di(2-ethylhexyl) Phthalate) µg/L 9 <2.0 1.8 - Ud CTR 69 4-Bromophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 70 Butylbenzyl Phthalate µg/L 8 <1.0 3000 - No CTR 71 2-Chloronaphthalene µg/L 8 <1.0 1700 - No CTR 72 4-Chlorophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 73 Chrysene µg/L 8 <1.0 0.0044 - Ud CTR 74 Dibenzo(a,h)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 75 1,2-Dichlorobenzene µg/L 10 <0.5 600 - No CA Prim. MCL 76 1,3-Dichlorobenzene µg/L 9 <0.5 400 - No CTR 77 1,4-Dichlorobenzene µg/L 10 <0.5 5 - No CA Prim. MCL 78 3,3 Dichlorobenzidine µg/L 8 <1.0 0.04 - Ud CTR 79 Diethyl Phthalate µg/L 8 <1.0 23000 - Ud CTR 80 Dimethyl Phthalate µg/L 8 <1.0 313000 - No CTR 81 Di-n-Butyl Phthalate µg/L 8 <1.0 2700 - No CTR 82 2,4-Dinitrotoluene µg/L 8 <1.0 0.11 - Ud CTR 83 2,6-Dinitrotoluene µg/L 8 <1.0 No Criteria - Uc No criteria 84 Di-n-Octyl Phthalate µg/L 8 <1.0 No Criteria - Uc No criteria CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-27 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 85 1,2-Diphenylhydrazine µg/L 8 <1.0 0.04 - Ud CTR 86 Fluoranthene µg/L 8 <1.0 300 - No CTR 87 Fluorene µg/L 8 <1.0 1300 - No CTR 88 Hexachlorobenzene µg/L 8 <1.0 0.00075 - Ud CTR 89 Hexachlorobutadiene µg/L 8 <1.0 0.44 - Ud CTR 90 Hexachlorocyclopentadiene µg/L 8 <1.0 50 - No CA Prim. MCL 91 Hexachloroethane µg/L 8 <1.0 1.9 - No CTR 92 Indeno(1,2,3-cd)Pyrene µg/L 8 <1.0 0.0044 - Ud CTR 93 Isophorone µg/L 8 <1.0 8.4 - No CTR 94 Naphthalene µg/L 8 <1.0 No Criteria - Uc No criteria 95 Nitrobenzene µg/L 8 <1.0 17 - No CTR 96 N-Nitrosodimethylamine µg/L 35 <0.001 0.00069 - No CTR 97 N-Nitrosodi-n-Propylamine µg/L 8 <1.0 0.005 - Ud CTR 98 N-Nitrosodiphenylamine µg/L 8 <1.0 5 - No CTR 99 Phenanthrene µg/L 8 <1.0 No Criteria - Uc No criteria 100 Pyrene µg/L 8 <1.0 960 - No CTR 101 1,2,4-Trichlorobenzene µg/L 9 <0.5 5 - No CA Prim. MCL 102 Aldrin µg/L 9 <0.005 0.00013 - Ud CTR 103 alpha-BHC µg/L 8 <0.005 0.0039 - Ud CTR 104 beta-BHC µg/L 8 <0.005 0.014 - No CTR 105 gamma-BHC µg/L 10 <0.005 0.019 - No CTR 106 delta-BHC µg/L 8 <0.005 No Criteria - Uc No criteria 107 Chlordane µg/L 9 <0.047 0.00057 - Ud CTR 108 4,4'-DDT µg/L 8 <0.005 0.00059 - Ud CTR 109 4,4'-DDE µg/L 8 <0.005 0.00059 - Ud CTR 110 4,4'-DDD µg/L 8 <0.005 0.00083 - Ud CTR 111 Dieldrin µg/L 9 <0.005 0.00014 - Ud CTR 112 alpha-Endosulfan µg/L 8 <0.005 0.056 - No CTR 113 beta-Endolsulfan µg/L 8 <0.005 0.056 - No CTR 114 Endosulfan Sulfate µg/L 8 <0.005 110 - No CTR 115 Endrin µg/L 10 <0.005 0.036 - No CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-28 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 116 Endrin Aldehyde µg/L 7 <0.005 0.76 - No CTR 117 Heptachlor µg/L 10 <0.005 0.00021 - Ud CTR 118 Heptachlor Epoxide µg/L 10 <0.005 0.00011 - Ud CTR 119- 125 PCBs sum µg/L 2 <0.5 0.00017 - Ud CTR 126 Toxaphene µg/L 9 <0.24 0.0002 - Ud CTR Non-Priority Pollutants Drinking Water Quality Objectives Aluminum µg/L 9 150 200 - No CA Sec. MCL Barium µg/L 9 42.9 1000 - No CA Prim. MCL Fluoride mg/L 9 0.7 1 - No BP Nitrate, Total (as N) mg/L 151 51.7 10 8.1 Yes EPA Prim. MCL Nitrate + Nitrite (as N) mg/L 7 43.4 10 - Yes CA Prim. MCL Nitrite, Total (as N) mg/L 106 5.1 1 <0.1 Yes CA Prim. MCL Methyl-tert-butyl ether µg/L 9 <1.0 5 - No CA Sec. MCL Styrene µg/L 9 <0.5 100 - No CA Prim. MCL Alachlor µg/L 9 <0.1 2 - No CA Prim. MCL Atrazine µg/L 9 <0.1 1 - No CA Prim. MCL Bentazon µg/L 9 <2.0 18 - No CA Prim. MCL Carbofuran µg/L 9 <5.0 18 - No CA Prim. MCL 2,4-D µg/L 9 5 70 - No CA Prim. MCL Dalapon µg/L 9 <10.0 200 - No CA Prim. MCL Dibromochloropropane (aka 1,2-Dibromo-3- Chloropropane) µg/L 8 <0.01 0.2 - No CA Prim. MCL Di(2-ethylhexyl)adipate µg/L 9 <5.0 400 - No CA Prim. MCL Dinoseb µg/L 9 <1.0 7 - No CA Prim. MCL Diquat µg/L 9 <2.0 20 - No CA Prim. MCL Endothall µg/L 9 <40 100 - No CA Prim. MCL Ethylene Dibromide (aka 1,2-Dibromoethane) µg/L 8 <0.02 0.05 - No CA Prim. MCL CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-29 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Glyphosate µg/L 9 <20.0 700 - No CA Prim. MCL Methoxychlor µg/L 10 <0.1 30 - No CA Prim. MCL Molinate µg/L 9 <0.1 20 - No CA Prim. MCL Oxamyl µg/L 9 <5.0 50 - No CA Prim. MCL Picloram µg/L 9 <1.0 500 - No CA Prim. MCL Simazine µg/L 9 <0.1 4 - No CA Prim. MCL Thiobencarb µg/L 9 <0.1 70 - No CA Prim. MCL 2,4,5-TP (Silvex) µg/L 9 <1.0 50 - No CA Prim. MCL Trichlorofluoromethane µg/L 9 <0.5 150 - No CA Prim. MCL 1,1,2-Trichloro-1,2,2- Trifluoroethane µg/L 3 <0.5 1200 - No CA Prim. MCL Xylenes µg/L 9 <0.5 1750 - No CA Prim. MCL Methylene blue activated substances (MBAS) µg/L 8 800 200 - Yes BP Un-ionized Ammonia (as N) mg/L [5] [5] 0.025 - Yes[5] BP Board 3 Basin Plan Water Quality Objectives for Agricultural Water Use Boron, Total µg/L 7 260 750 - No BP Cobalt, Total µg/L 7 4.0 50 - No BP Iron, Total µg/L 8 520 5000 - No BP Lithium, Total µg/L 7 14 2500d - No BP Manganese, Total µg/L 8 42.8 200 - No BP Molybdenum, Total µg/L 7 17 10 - Yes BP Vanadium, Total µg/L 7 5 100 - No BP San Luis Obispo Creek Sub-Area Surface Water Quality Objectives Total Dissolved Solids mg/L 38 990 650 470- 750[6] Yes BP Chloride mg/L 39 209 100 31- 92[6] Yes BP Sulfate, Total, (as SO4) mg/L 6 142 100 - Yes BP Sodium mg/L 35 181 50 29- 72[6] Yes BP [1] Number of data points available for the RPA. [2] If there is a detected value, the highest reported value is summarized in the table. If there are no detected values, if available, the lowest MDL is summarized in the table. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-30 [3] RPA Results: = Yes, if MEC > WQO/WQC, or B > WQO/WQC and MEC is detected; = No, if MEC and B are < WQO/WQC or all effluent data are undetected; = (Uc) Undetermined, if no criteria have been promulgated; = (Ud) Undetermined, for lack of data. As described in section 1.3 in the SIP, if monitoring results show non-detect for all samples of a pollutant and if all reported detection limits of the pollutant in the effluent are greater than or equal to the C value, the RWQCB shall require additional monitoring for the pollutant in place of a water quality-based effluent limitation. For pollutants with a result of Ud, additional monitoring is established through this permit. [4] Basis of Most Stringent Criteria CTR - California Toxics Rule’ CA Prim. MCL - California Primary MCL CA Sec. MCL - California Secondary MCL EPA Prim. MCL - EPA Primary MCL EPA Sec. MCL - EPA Secondary MCL NAWQC - National Ambient Water Quality Criteria BP - Central Coast Regional Board 2019 Basin Plan SWRCB 2017-0027 - Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California—Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. [5] The reasonable potential for the effluent to exceed the 2019 Basin Plan water quality objective for San Luis Obispo Creek for un-ionized ammonia is based on 93 concurrent upstream (RSW-004) and downstream (RSW-005) monitoring data results from December 2014 through April 2020. [6] Range of measured values. The 2019 Basin Plan Water Quality Objective for this pollutant is an annual mean. 4.3.4. WQBEL Calculations As detailed in Table F-6, reasonable potential has been determined for mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, total nitrate (as N), nitrate + nitrite (as N), total nitrite (as N), un- ionized ammonia (as N), methylene blue activated substances (MBAS), total molybdenum, total dissolved solids (TDS), sulfate, sodium, and chloride. The following example demonstrates how WQBELs were established for this Order for chlorodibromomethane. Step 1: For each water quality criterion/objective, an effluent concentration allowance (ECA) is calculated from the following equation to account for dilution and background levels of each pollutant. ECA = C + D (C – B), when C > B, and ECA = C when C ≤ B, Where, C = the applicable water quality criterion (adjusted for receiving water hardness and expressed as total recoverable metal, if applicable). CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-31 D = the dilution credit (here D = 0, as the Central Coast Water Board has no information with which to justify credit for dilution). B = the background concentration As discussed above, for this Order, dilution was not allowed; therefore: ECA = C For chlorodibromomethane, the applicable water quality criteria are: ECAHuman Health = 0.401 μg/L Step 2: For each ECA based on an aquatic life criterion, the long -term average discharge condition (LTA) is determined by multiplying the ECA times a factor (multiplier), which adjusts the ECA to account for effluent variability. The multiplier varies depending on the coefficient of variation (CV) of the data set and whether it is an acute or chronic criterion/objective. Table 1 of the SIP provides pre-calculated values for the multipliers based on the value of the CV. When the data set contains less than 10 sample results, or 80 percent or more of the data are reported as non -detect (ND), the CV is set equal to 0.6. Derivation of the multipliers is presented in Section 1.4 of the SIP. LTAacute = ECAacute x Multiplieracute 99 LTAchronic= ECAchronic x Multiplierchronic 99 Typically, historic effluent data is used to develop the acute and chronic LTA using equations provided in Section 1.4, Step 3 of the SIP (Table 1 of the SIP also provides this data up to three decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the development of this permit and LTA for acute and chronic were unnecessary to calculate. Step 3: WQBELs, including an AMEL and a MDEL are calculated using the most limiting (the lowest) LTA. The LTA is multiplied times a factor that accounts for averaging periods and exceedance frequencies of the effluent limitations, and for the AMEL, the effluent monitoring frequency. Here, the sampling frequency is set equal to 1 (n = 1). The 99th percentile occurrence probability was used to determine the MDEL multiplier and a 95th percentile occurrence probability was used to determine the AMEL multiplier. Table 2 of the SIP presents the MDEL and AMEL multipliers as a function of the CV. When the data set contains less than 10 sample results, or when 80 percent or more of the data set is reported as non-detect (ND), the CV is set equal to 0.6. Otherwise, the CV is calculated as the standard deviation divided by the mean. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-32 No. of Samples No. of Samples Per Month (n) CV 73 1 0.6 Step 4: Calculate the WQBELs by multiplying the LTA by a factor (multiplier). WQBELs are expressed as AMEL and MDEL. The multiplier is a statistically based factor that adjusts the LTA for the averaging periods and exceedance frequencies of the criteria/objectives and the effluent limitations. The value of the multiplier varies depending on the probability basis, the coefficient of variation (CV) of the data set, the number of samples (for AMEL) and whether it is a monthly or daily limit. Table 2 of the SIP provides pre-calculated values for the multipliers based on the value of the CV and the number of samples. Equations to develop the multipliers in place of using values in the tables are provided in Section 1.4, Step 5 of the SIP and will not be repeated here. AMELaquatic life = LTA x AMELmultiplier 95 MDELaquatic life = LTA x MDELmultiplier 99 AMEL multipliers are based on a 95th percentile occurrence probability, and the MDEL multipliers are based on the 99th percentile occurrence probability. If the number of samples is less than four (4), the default number of samples to be used is four (4). Equations provided in Section 1.4, Step 5 of the SIP are used to develop the AMEL and MDEL for aquatic life using (Table 2 of the SIP also provides this data up to two decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the developmen t of this permit and AMEL and MDEL for aquatic life were unnecessary to calculate. Calculation of human health AMEL and MDEL: Step 5: For the ECA based on human health, set the AMEL equal to the ECAhuman health AMELhuman health = ECAhuman health For chlorodibromomethane: AMELhuman health = 0.401 μg/L Step 6: Calculate the MDEL for human health by multiplying the AMEL by the ratio of the MultiplierMDEL to the MultiplierAMEL. Table 2 of the SIP provides pre-calculated ratios to be used in this calculation based on the CV and the number of samples. MDELhuman health = AMELhuman health x (MultiplierMDEL / MultiplierAMEL) For chlorodibromomethane the following data were used to develop the MDELhuman health: No. of Samples Per Month CV MultiplierMDEL 99 MultiplierAMEL 95 Ratio CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-33 1 0.6 3.11 1.55 2.01 MDELhuman health = 0.401 μg/L x 2.01 = 0.806 μg/L Step 7: Select the lower of the AMEL and MDEL based on aquatic life and human health as the water-quality based effluent limit for the Order. For chlorodibromomethane, the AMELhuman health and MDELhuman health were 0.401 μg/L and 0.806 μg/L respectively. Thus, the human health criteria-based effluent limitations were more stringent and were considered in the Order. 4.3.4.1 Constituents with Reasonable Potential 4.3.4.1.1 Mercury. The RPA used effluent data from December 2014 through December 2022 and showed that there was a reasonable potential for the discharge to exceed the total recoverable mercury criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.012 µg/L and an MDEL of 0.024 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total recoverable mercury. 4.3.4.1.2 Chlorodibromomethane. The previous Order established an AMEL of 0.40 µg/L and an MDEL of 1.0 µg/L for chlorodibromomethane (dibromochloromethane). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chlorodibromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.4 µg/L and an MDEL of 0.81 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chlorodibromomethane. 4.3.4.1.3 Chloroform. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chloroform criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chloroform. 4.3.4.1.4 Dichlorobromomethane. The previous Order established an AMEL of 0.56 µg/L and an MDEL of 1.0 µg/L for dichlorobromomethane. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the dichlorobromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.56 µg/L and an MDEL of 0.96 µg/L have been established in this permit. Effluent and receiving water CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-34 monitoring and reporting requirements have also been established for dichlorobromomethane. 4.3.4.1.5. Methylene Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the methylene chloride criteria; therefore, effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 4.7 µg/L and an MDEL of 9.45 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for methylene chloride. 4.3.4.1.6. Pentachlorophenol. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the pentachlorophenol criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for pentachlorophenol. 4.3.4.1.8. Nitrate and Nitrate + Nitrite. As previously discussed, an effluent limitation for total nitrate (as N) was established through the TMDL for nitrate-nitrogen discharges to San Luis Obispo creek and was retained from the previous permit. Additionally, an effluent limitation for total nitrite (as nitrogen) is established in this order. A separate effluent limitation has not been established for nitrate+nitrite. Nitrate+nitrite is the sum of nitrate and nitrite, and therefore is duplicative of the two established effluent limitations. 4.3.4.1.9. Nitrite. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the total nitrite (as N) criteria, and therefore an effluent limitation is established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 1.0 mg/L has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total nitrite (as N). 4.3.4.1.10. Methylene blue activated substances (MBAS). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the MBAS criteria of 0.2 mg/L from the 2019 Basin Plan. The 0.2 mg/L effluent limitation established in this order is equivalent to the most stringent water quality objective in the 2019 Basin Plan . Effluent and receiving water monitoring and reporting requirements have also been established for MBAS. 4.3.4.1.11 Un-ionized Ammonia. The 2019 Basin Plan includes a water quality objective for un-ionized ammonia (NH3) of 0.025 mg/L. The previous Order did not establish an effluent limitation for un-ionized ammonia. The previous Order incorporated the Basin Plan objective as a receiving water limitation. From December 2014 through April 2020, the Discharger collected 93 concurrent upstream (RSW -004) and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-35 downstream (RSW-005) samples to determine un-ionized ammonia concentrations in the receiving water. The effluent caused the receiving water to exceed the Basin Plan objective on 29 occasions. Reasonable potential was found for un-ionized ammonia, and an effluent limitation and monitoring requirement were established for un -ionized ammonia. The effluent limitation of 0.025 mg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. 4.3.4.1.12. Molybdenum. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the molybdenum criteria of 10 µg/L from the 2019 Basin Plan. An effluent limitation of 10 µg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for molybdenum. 4.3.4.1.13. Total Dissolved Solids. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the total dissolved solids criteria of 650 mg/L in the Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for total dissolved solids. 4.3.4.1.14. Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the chloride criteria of 100 mg/L from the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek . Effluent and receiving water monitoring and reporting requirements have also been established for chloride. 4.3.4.1.15. Sulfate. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sulfate criteria of 100 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sulfate. 4.3.4.1.16. Sodium. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sodium criteria of 50 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sodium. 4.3.4.2 Constituents with No Reasonable Potential As detailed in Table F-8, constituents that were analyzed and received a “No” in the “RPA Result” column did not have a reasonable potential to cause or contribute to an excursion above the 126 U.S. EPA priority toxic pollutants, title 22 MCLs, or any CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-36 numeric water quality objectives included in any State Water Board plans or the 2019 Basin Plan. WQBEL’s are not included in this Order for constituents that do not demonstrate reasonable potential to cause or contribute to an instream excursion of an applicable water quality objective; however monitoring for priority toxic and title 22 pollutants is established in this Order. Most constituents with no reasonable potential are not discussed in this order. This section provides a discussion on the constituent with no reasonable potential for which an effluent limitation has not been retained from the previous order. 4.3.4.2.1 N-nitrosodimethylamine. The previous Order included an AMEL of 0.00069 µg/L and an MDEL of 0.0014 µg/L for n-nitrosodimethylamine. Several sample results analyzed during 2016 showed effluent limitation exceedances. However, in a letter dated February 9, 2017, the Discharger provided additional information to the Central Coast Water Board describing that the cause of the apparent exceedances was due to the test method used to analyze the samples. The Minimum Level (ML) established for n-nitrosodimethylamine in Appendix 4 of the SIP is 5 µg/L for samples analyzed by gas chromatography/ mass spectrometry. The Discharger was using EPA Method 1625M, an “ultra-low-level” method, which is not an approved method in 40 CFR part 136 and is not appropriate for compliance monitoring. The Discharger notified the Central Coast Water Board of its plan to return to using EPA Method 625 to measure n- nitrosodimethylamine in the effluent instead of the “ultra-low-level” the Discharger used in 2016 (i.e., EPA Method 1625M). On May 15, 2017, the Central Coast Water Board provided a written response that concurred with the Discharger regarding the return to EPA Method 625 and that the n-nitrosodimethylamine effluent concentrations reported in 2016 should not have been reported as effluent limitation exceedances because results below the ML of 5 µg/L are not considered violations according to the SIP. The RPA used effluent data from December 2014 through December 2022 that was analyzed using the correct test method and found that there was not reasonable potential for an exceedance of a water quality objective. An effluent limitation of n- nitrosodimethylamine has not been retained for this Order. Additional discussion is included in section 4.4.1 Ant-Backsliding Requirements and section 4.4.1 Antidegradation Policies of this fact sheet. 4.3.5. Whole Effluent Toxicity (WET) Aquatic toxicity is the adverse response of aquatic organisms from exposure to chemical or physical agents, or their synergistic effects in effluent or ambient water. Acute aquatic toxicity refers to adverse response (typically lethality) from a short -term exposure. Chronic aquatic toxicity generally refers to longer exposure duration and measures of both lethal and sub-lethal adverse response. WET testing protects receiving waters from the aggregate toxic effect of a mixture of pollutants that may be present in effluent. The Basin Plan establishes a narrative WQO which states that all waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-37 Survival of aquatic organisms in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge or for another control water. The WE T approach allows for protection of the narrative “no toxics in toxic amounts” criterion while implementing numeric criteria for toxicity. For compliance with the Basin Plan’s narrative toxicity objective and the 2022 Toxicity Provisions, this Order requires the Discharger to conduct WET testing for acute and chronic toxicity in accordance with the Test of Significant Toxicity (TST) statistical approach, as specified in section 5 of the MRP (Attachment E). 4.3.5.1. Test of Significant Toxicity (TST) In 2010, U.S. EPA endorsed the TST statistical hypothesis testing approach, described in the National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, as an improved hypothesis-testing tool to evaluate data from U.S EPA’s toxicity test methods. The TST hypothesis testing approach more reliably identifies toxicity —in relation to the chronic (0.25 or more) and acute (0.20 or more) mean responses of regulatory management concern—than the No Observed Effect Concentration (NOEC) hypothesis-testing approach previously used. On December 1, 2020, the State Water Board adopted Resolution No. 2020 -0044, establishing the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries (ISWEBE Plan), and adopting statewide numeric WQOs for both acute and chronic toxicity and a program of implementation to control toxicity, which are collectively known as the Toxicity Provisions. The Toxicity Provisions, which were revised on October 5, 2021, standardized the regulation of aquatic toxicity for all non- oceanic surface waters.3 U.S. EPA’s Test of Significant Toxicity Design, or TST, approach is an essential component of the Toxicity Provisions as it forms the basis for utilizing numeric WQOs and acts as the primary means of determining compliance with WET effluent limitations. This Order requires application of the TST approach for statistical analysis of WET data. 4.3.5.1.1. Test of Significant Toxicity Design The TST null hypothesis (Ho) for acute toxicity is: “mean discharge IWC response ≤0.80 × mean control response”, where 0.80 is the regulatory management decision (RMD). The TST null hypothesis (Ho) for chronic toxicity is: “mean discharge IWC response ≤0.75 × mean control response”, where 0.75 is the RMD. The null hypotheses for acute and chronic toxicity described in the TST are assigned as numeric WQOs for acute and chronic toxicity in sections II.C.1 and II.C.2 of the Toxicity Provisions. A test result t hat rejects the null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The TST approach is a t -test (formally Student’s t- 3 The Toxicity Provisions were approved by the Office of Administrative Law on April 25, 2022, and by U.S. EPA on May 1, 2023. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-38 test), a statistical analysis comparing two sets of replicate observations —in the case of WET tests, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”)). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month, or in consecutive calendar months, result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be re ported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). Compliance with the toxicity limitation is demonstrated by rejecting the null hypothesis and reporting “Pass”. When the toxicity test results in a “Fail” the Discharger must initiate accelerated monitoring as specified in section 5.3 of the MRP. After accelerated monitoring, if conditions of chronic toxicity are found to persist, the Discharger will be required to conduct a TRE, as described in section 5.4 of the MRP. See section III.B.3 of the Toxicity Provisions for a detailed step-by-step description of the TST statistical method. 4.3.5.2. WET Reasonable Potential Analysis To determine the need for acute and/or chronic toxicity effluent limitations, the Central Coast Water Board conducted a RPA using the TST approach. In conducting the RPA, the Central Coast Water Board considered and evaluated all acute and chronic toxicity data generated during the previous permit term since the data is representative of the actual effluent quality from the Facility. Reasonable potential exists if any of the acute or chronic toxicity tests result in a “Fail” or if the percent effect at the IWC is greater than 10 percent. The IWC for Discharge Point 001 is 100 percent effluent. The Discharger conducted eight acute and 26 chronic toxicity tests using the species Pimephales promelas between October 2015 and October 2022, as shown in Table F - 10 below. Analysis using the TST approach concluded that the Discharger failed zero acute toxicity tests, and 14 chronic toxicity tests, representing a fail rate of 54 percent. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-39 After extensive City staff and consultant review, summarized in the Toxicity Reduction Evaluation Workplan Conclusion report submitted to the Central Coast Regional Water Quality Control Board on May 22, 2019, all Effluent 001 sampling events from October 2016 to October 2018 exhibited at least one of the three qualifying data interpretations of sporadic mortality, suggesting biological interference was the cause of observed toxicity. The Central Coast Water Board reviewed the TRE Workplan and maintained that the failed chronic test results would remain on record. These chronic toxicity test results were used to conclude that the discharge has reasonable potential to cause or contribute to an exceedance of chronic toxicity WQOs and that the discharge is subject to chronic toxicity effluent limitations. In addition, section III.C.5.c. of the Toxicity Provisions requires establishment of chronic toxicity effluent limitations if a POTW is authorized to discharge at a rate equal to or greater than 5.0 MGD and is required to have a pretreatment program by the terms of 40 CFR section 403.8(a). The permitted flow rate for the Facility is 5.4 MGD, and the Discharger is required to have a pretreatment program. Therefore, based on the determination of the RPA, and requirements contained in the Toxicity Provisions, the Order establishes MDEL and MMEL effluent limitations for chronic toxicity. Table F-9. Summary of Acute and Chronic Toxicity Test Results Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 10/6/2015 Pass 2.50 Survival Acute 10/4/2016 Pass 0.00 Survival Acute 10/3/2017 Pass 10.00 Survival Acute 10/30/2018 Pass 0.00 Survival Acute 10/15/2019 Pass 7.50 Survival Acute 10/28/2020 Pass 0.00 Survival Acute 10/5/2021 Pass 0.00 Survival Acute 10/4/2022 Pass 0.00 Survival Acute 10/6/2015 Pass 8.68 Growth Chronic 10/6/2015 Pass 6.78 Survival Chronic 10/4/2016 Pass -13.56 Growth Chronic 10/4/2016 Pass 13.33 Survival Chronic 10/3/2017 Fail 31.69 Growth Chronic 10/3/2017 Fail 40.68 Survival Chronic 10/24/2017 Fail 49.63 Growth Chronic 10/24/2017 Fail 68.33 Survival Chronic 11/28/2017 Pass 17.20 Growth Chronic 11/28/2017 Pass 10.91 Survival Chronic 12/12/2017 Fail 43.78 Growth Chronic 12/12/2017 Fail 58.33 Survival Chronic 8/21/2018 Fail 19.95 Growth Chronic 8/21/2018 Fail 31.67 Survival Chronic 7/31/2018 Pass 14.48 Growth Chronic CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-40 Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 7/31/2018 Fail 34.48 Survival Chronic 10/30/2018 Pass 4.56 Growth Chronic 10/30/2018 Fail 18.33 Survival Chronic 10/15/2019 Pass -12.63 Growth Chronic 10/15/2019 Pass 1.75 Survival Chronic 10/28/2020 Pass -7.95 Growth Chronic 10/28/2020 Pass 0.00 Survival Chronic 10/5/2021 Pass -2.02 Growth Chronic 10/5/2021 Pass 0.00 Survival Chronic 10/4/2022 Pass 3.00 Growth Chronic 10/4/2022 Pass 0.00 Survival Chronic 4.3.5.3. Acute Aquatic Toxicity Although the Discharger reported no acute toxicity test failures from the eight acute toxicity tests conducted during the previous permit term, this permit retains annual effluent monitoring requirements for acute toxicity established in Order No. R3-2014- 0033 due to persistent failure of chronic toxicity tests during the previous permit term, which resulted in a required TRE being conducted. The Order implements federal guidelines (Regions 9 & 10 Guidance for Implementing Whole Effluent Toxicity Testing Programs) by requiring the Discharger to conduct acute species sensitivity testing as described in section 5 of the MRP (Attachment E). This Order requires the Discharger to conduct a screening test using a vertebrate and invertebrate species. After the screening test is completed, the Discharger is required to use the most sensitive species in future acute toxicity testing if the most sensitive species is found not to be Pimephales promelas. 4.3.6. Basin Plan and Bacteria Provisions 4.3.6.1. Bacteria Provisions. The Facility receives domestic wastewater and discharges to surface waters with the water contact recreation beneficial use (REC-1). Because of the nature of domestic wastewater, discharges from publicly owned treatment works with these discharge characteristics have the reasonable potential to cause or contribute to an exceedance of water quality criteria for bacteria. On August 7, 2018, the State Water Board adopted Part 3 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California – Bacteria Provisions and a Water Quality Standards Variance Policy (Bacteria Provisions), which establishes bacteria water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). Under the statewide Bacteria Provisions, the water quality objective protective of the REC-1 beneficial use is, in waters where the salinity is less than one part per thousand (ppth) 95 percent or more of the time: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-41 • The concentration of E. coli shall not exceed 100 colony forming units (cfu) per 100 milliliters (mL) as a six-week rolling geometric mean, calculated weekly. • A statistical threshold value (STV) of 320 cfu/100 mL for E. coli shall not be exceeded by more than 10 percent of the samples collected in a calendar month and calculated in a static manner. Order R3-2014-0033 established effluent limitations for coliform bacteria based on applicable water quality objectives in the Basin Plan for San Luis Obispo Creek. The bacteria water quality objectives in the Bacteria Provisions supersede numeric water quality objectives for bacteria for the REC-1 beneficial use contained in a water quality control plan prior to February 4, 2019. Because San Luis Obispo Creek salinity is less than one part per thousand (ppth) 95 percent or more of the time , this Order establishes E. coli effluent limitations for Discharge Point 001, based on the water quality objectives in the Bacteria Provisions, in place of the previous fecal coliform effluent limitations. 4.3.6.2. Dissolved Oxygen. In order to protect the beneficial uses of San Luis Obispo Creek, Order R3-2014-0033 retained an effluent limit for dissolved oxygen, prohibiting the discharge from containing a dissolved oxygen concentration of less than 4.0 mg/L or so low that it adversely affects beneficial uses. 4.3.6.3. Nitrate. San Luis Obispo Creek is included on the 303(d) List as impaired for nutrients. Central Coast Water Board Resolution R3-2005-0106 established TMDLs for nitrate for discharges to San Luis Obispo Creek. Due to federal and State anti- backsliding regulations, nitrate remains a pollutant of concern for this discharge and the monthly average effluent limitation of 10 mg/L as N is retained from the previous Order. 4.3.6.4. pH. Federal regulations, 40 CFR 133, establish technology-based effluent limitations for pH. The secondary treatment standards require the pH of the effluent to be no lower than 6.0 and no greater than 9.0 standard units. However, the Basin Plan establishes a WQO for pH of between 6.5 to 8.3 standard units for the protection of receiving waters with the beneficial use of Municipal and Domestic Supply (MUN), Agricultural Supply (AGR), and Water Recreation (REC1 and REC2). The Basin Plan establishes a WQO for pH between 7.0 to 8.5 standard units for the beneficial use of Freshwater Habitat (COLD and WARM) and Fish Spawning (SPWN). The previous Order established an effluent limitation of 6.5 to 8.3. However, since San Luis Obispo Creek has MUN, AGR, REC1, REC2, COLD, WARM, and SPWN beneficial uses, a pH effluent limitation of 7.0 to 8.3 is appropriate in order to protect all beneficial uses. This Order updates the previous effluent limitation of 6.5 to 8.3 from the previous Order, based on the water quality objective for the Municipal and Domestic Supply (MUN) beneficial use. For the protection of the COLD beneficial use, this Order applies a receiving water limitation of 7.0 to 8.3, with no change in normal ambient pH levels above 0.5. 4.3.6.5. Oil and Grease. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works has the reasonable potential to cause or contribute to an exceedance of water quality criteria for oil and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-42 grease. The Basin Plan establishes a narrative effluent limitation for oil and grease, which states, “Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. The previous Order contained an AMEL and MDEL of 5.0 mg/L and 10 mg/L, respectively. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.3.6.6. Floating Material. Discharge of treated wastewater through Discharge Point No. 001 shall not contain floating material, including solids, liquids, foams, and scum in concentrations that cause nuisance or adversely affect beneficial uses. This effluent limitation is consistent with the Basin Plan. 4.3.6.7. Settleable Solids. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works have the reasonable potential to cause or contribute to an exceedance of water quality criteria for settleable solids. The Basin Plan establishes a narrative effluent limitation for settleable solids, which states, “Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely aff ects beneficial uses. The previous Order contained an average monthly effluent limitation (AMEL) of 0.1 mL/L. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.4. Final Effluent Limitation Considerations 4.4.1. Anti-Backsliding Requirements Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. 122.44(l) prohibit backsliding in NPDES permits. These anti-backsliding provisions require effluent limitations in a reissued permit to be as stringent as those in the previous permit, with some exceptions where limitations may be relaxed. All effluent limitations in this Order are at least as stringent as the effluent limitations in the previous Order. An effluent limitation for n-nitrosodimethylamine has not been retained from the previous Order because current data analysis shows no reasonable potential. The elimination of this WQBEL is consistent with the exception to the CWA's anti-backsliding requirements expressed at §402 (0)(2)(B)(i) of the Act, which allows a reissued permit to include less stringent limitations when information is available that was not available at the time of permit issuance (other than revised regulations, guidance, or test methods), and that would have justified the application of a less stringent effluent limitation at the time of permit issuance. The removal of the limitation of n- nitrosodimethylamine is based on new data, which was generated during the term of previous Order, and which demonstrates no reasonable potential for discharges from the Facility to cause or contribute to exceedances of applicable WQOs for this pollutant. Therefore, effluent limitations for these pollutants from the previous Order are not retained in this Order. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-43 4.4.2. Antidegradation Policies 40 CFR section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal antidegradation policy. On October 28, 1968, the State Water Board established California’s antidegradation policy when it adopted Resolution Number 68-16, Statement of Policy with Respect to Maintaining the Quality of the Waters of the State. Resolution Number 68-16 requires that existing water quality be maintained unless degradation is justified based on specific findings. The State Water Board has, in State Water Board Order Number 86-17 and an October 7, 1987 guidance memorandum, interpreted Resolution Number 68-16 to be fully consistent with the federal antidegradation policy contained in 40 CFR section 131.12. Similarly, CWA section 303(d)(4)(B) and 40 CFR section 131.12 require that all permitting actions be consistent with the federal antidegradation policy. Together, the state and federal antidegradation policies are designed to ensure that a water body will not be degraded resulting from the permitted discharge. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The renewal of this NPDES permit is consistent with the anti-degradation policy because it is not expected to allow degradation of receiving water quality. No reduction in the existing level of wastewater treatment is anticipated. In addition, the renewal of the NPDES permit will not lower the surface water quality because the conditions in this Order are at least as stringent as the previous permit except for limits described in section 4.4.1 of the Fact Sheet. Specifically, the removal of the final effluent limitation for n-nitrosodimethylamine is consistent with the antidegradation policy because the discharge did not exhibit reasonable potential to exceed the water quality objective, and it is not expected to degrade the water quality of the receiving water. Effluent and receiving water monitoring for this pollutant continue to be required under this Order to ensure effluent and receiving water concentrations do not exceed the objective. 4.4.3. Stringency of Requirements for Individual Pollutants This Order contains both technology-based and water quality-based effluent limitations for individual pollutants. The technology-based effluent limitations consist of restrictions on BOD and TSS. This Order’s technology-based pollutant restrictions implement the minimum applicable federal technology-based requirements. In addition, this Order contains effluent limitations more stringent than the minimum federal technology-based requirements that are necessary to meet water quality standards. For pH, BOD, and TSS both technology-based effluent limitations and water quality-based effluent limitations are applicable. The more stringent of these effluent limitations are implemented by this Order. These limitations are not more stringent than required by the CWA. Water quality-based effluent limitations have been derived to implement water quality objectives that protect beneficial uses. Both the beneficial uses and the water quality objectives have been approved pursuant to federal law and are the applicable federal water quality standards. To the extent that toxic pollutant water CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-44 quality-based effluent limitations were derived from the CTR, the CTR is the applicable standard pursuant to 40 C.F.R. 131.38. The procedures for calculating the individual water quality-based effluent limitations for priority pollutants are based on the CTR implemented by the SIP, which was approved by U.S. EPA on May 18, 2000. Any water quality objectives and beneficial uses submitted to U.S. EPA prior to May 30, 2000, but not approved by U.S. EPA before that date, are nonetheless “applicable water quality standards for purposes of the CWA” pursuant to 40 C.F.R. 131.21(c)(1). Collectively, this Order’s restrictions on individual pollutants are no more stringent than required to implement the requirements of the CWA. 4.4.4. Summary of Final Effluent Limitations 4.4.4.1. Effluent Limitations. The following effluent limitations are applicable to the discharge of disinfected tertiary treated wastewater from the Facility at Discharge Point No. 001. Table F-10. Final Effluent Limitations – Discharge Point EFF-001 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1,351 2,252 - - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - - TSS lbs/day[1] 425 1,351 3,378 - - - - pH[2],[3] standard units - - - 7.0 8.3 - - Oil and Grease mg/L 5 - 10 - - - - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-45 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - - Dissolved Oxygen mg/L - - - 4.0 - - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.01 2 - 0.024 - - - - Chlorodibromom ethane (Dibromochlorom ethane) µg/L 0.40 - 0.81 - - - - Chloroform µg/L 60 - 120.6 - - - - Dichlorobromom ethane µg/L 0.56 - 0.96 - - - - Methylene Chloride µg/L 4.7 - 9.45 - - - - Pentachlorophen ol µg/L 0.28 - 0.56 - - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - - Nitrite, Total mg/L 1 - - - - - - Un-ionized Ammonia mg/L 0.02 5 - - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - - Molybdenum mg/L 0.01 - - - - - - Total Dissolved Solids mg/L - - - - - 650[10] CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-46 [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 6.5-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 6.5-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0-9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 6.5-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Chloride mg/L - - - - - 100[10] Sodium mg/L - - - - - 50[10] Sulfate mg/L -- - - - - 100[10] Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-47 with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 - day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in -stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP -Attachment E). [10] Based on a 12-month running mean. 4.5. Interim Effluent Limitations – Not Applicable 4.6. Land Discharge Specifications – Not Applicable 4.7. Recycling Specifications This Order allows the production and onsite use of disinfected tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements in the State Water Board’s Recycled Water Policy, and those established by DDW at title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. This Order includes water reclamation requirements for the Facility pursuant to the State Water Board’s Division of Drinking Water recommendations submitted to the Central Coast Water Board. This Order requires the Discharger to adhere to the requirements outlined in section 4.3 and any additional conditions pursuant to specifications in updated title 22 engineering reports approved by the State Water Board’s Division of Drinking Water. 4.8. Point of Compliance for Effluent Limitations 4.8.1. The Discharger must comply with the effluent limitations established in this order at location EFF-001. The facility includes a long concrete pipe that sends treated effluent from the facility to San Luis Obispo Creek. In previous permits, the discharge was monitored at the end of the pipe, just before it mixes with San Luis Obispo Creek. Due to safety and cost concerns, the Discharger requested to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-48 perform the majority of their compliance monitoring at the beginning of the pipe. The beginning of the pipe is referred to as EFF-001A and the end of the pipe is referred to as EFF-001B. 5. RATIONALE FOR RECEIVING WATER LIMITATIONS 5.1. Surface Water Receiving water quality is a result of many factors, some unrelated to the discharge. This Order considers these factors and is designed to minimize the influence of the discharge on the receiving water. Specific water quality objectives established by the Basin Plan to meet this goal for all inland surface waters are included as receiving water limitations in section 5.1. of this Order. 6. RATIONALE FOR PROVISIONS 6.1. Standard Provisions Standard Provisions, which apply to all NPDES permits in accordance with 40 C.F.R. section 122.41, and additional conditions applicable to specified categories of permits in accordance with 40 C.F.R. section 122.42, are provided in Attachment D. The Discharger must comply with all standard provisions and with those additional conditions that are applicable under section 122.42. Sections 122.41(a)(1) and (b) through (n) of 40 C.F.R. establish conditions that apply to all state-issued NPDES permits. These conditions must be incorporated into the permits either expressly or by reference. If incorporated by reference, a specific citation to the regulations must be included in the Order. Section 123.25(a)(12) of 40 C.F.R. allows the state to omit or modify conditions to impose more stringent requirements. In accordance with 40 C.F.R. section 123.25, this Order omits federal conditions that address enforcement authority specified in 40 C.F.R. section 122.41(j)(5) and (k)(2) because the enforcement authority under the California Water Code is more stringent. In lieu of these conditions, this Order incorporates by reference California Water Code section 13387(e). 6.2. Special Provisions 6.2.1. Reopener Provisions The Order may be modified in accordance with the requirements set forth at 40 C.F.R. parts 122 and 124, to include appropriate conditions or limits based on newly available information, or to implement any, new state water quality objectives that are approved by the U.S. EPA. As effluent is further characterized through additional monitoring, and if a need for additional effluent limitations becomes apparent after additional effluent characterization, the Order will be reopened to incorporate such limitations. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential to cause, or contributes to an excursion above a SIP water quality objective. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-49 6.2.2. Special Studies and Additional Monitoring Requirements 6.2.2.1. Whole Effluent Toxicity. The Basin Plan states, “All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board.” The Basin Plan further states, “Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality condition, shall not be less than that for the same waterbody in areas unaffected by the waste discharge…” and that effluent limitations based upon acute bioassays of effluent will be prescribed where appropriate. This permit establishes acute and chronic monitoring requirements, and chronic toxicity effluent limitations in accordance with the 2022 Toxicity Provisions, which incorporates the narrative objectives of the Basin Plan. The Order and MRP require the Discharger to conduct accelerated toxicity testing for exceedances of the acute toxicity WQOs, as described in the Toxicity Provisions, and/or chronic toxicity effluent limitations. If the accelerated testing demonstrates toxicity, the Discharger is required to submit a TRE Work Plan in accordance with U.S. EPA guidance, which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharge will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TIE process in accordance with the Work Plan if the results of toxicity testing exceed the effluent limitation or trigger for toxicity. 6.2.3. Best Management Practices and Pollution Prevention 6.2.3.1. Pollutant Minimization Program. The Discharger is required to minimize the discharge of pollutants consistent with the requirements of section 2.4.5.1 of the SIP. The goal of the Pollutant Minimization Program is to reduce all potential sources of a priority pollutant through pollutant minimization strategies to maintain the effluent concentration at or below water quality -based effluent limitations. 6.2.3.2. Salt and Nutrient Management Program. Section VI.C.3 of the previous Order required the Discharger to conduct a Salt Management Study to control levels of TDS, chloride, sodium, sulfate, and boron (collectively referred to as salts) in discharges from the Facility and attain applicable WQOs for salts in the San Luis Obispo Creek sub-basin of the Estero Bay Drainage Basin. Data from the term of the previous Order indicated the Facility has reasonable potential to cause or contribute to downstream impairment for salts loading. Therefore, in addition to effluent and receiving water monitoring for TDS, chloride, sulfate, boron and sodium, this Order requires the Discharger to continue to update and implement the Salt Management Program and provide CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-50 annual reports. Additionally, the Discharger shall develop and implement a Nutrient Management Program as part of the Salt and Nutrient Management Program, as discussed in section 6.3.3.1. of this Order, based on the Recycled Water Policy discussed in section 3.5.3. of this Fact Sheet. 6.2.4. Construction, Operation, and Maintenance Specifications 6.2.4.1 The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.2.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.2.5.1. Pretreatment. This Order contains pretreatment requirements consistent with applicable effluent limitations, national standards of performance, and toxic and performance effluent standards established pursuant to sections 208(b), 301, 302, 303(d), 304, 306, 307, 403, 404, 405, and 501 of the CWA, and amendments thereto. This permit contains requirements for the implementation of an effective pretreatment program pursuant to section 307 of the CWA; 40 CFR 35 and 403; and/or Title 23, CCR section 2233. 6.2.5.2. Collection System. The State Water Board issued General Waste Discharge Requirements for Sanitary Sewer Systems, Water Quality Order 2022-0103- DWQ (General Order) on December 6, 2022. The General Order requires public agencies that own or operate sanitary sewer systems with sewer lines one mile of pipe or greater to enroll for coverage and comply with the General Order. The General Order requires agencies to develop sanitary sewer management plans and report all sanitary sewer overflows, among othe r requirements and prohibitions. The General Order contains requirements for operation and maintenance of collection systems and for reporting and mitigating sanitary sewer overflows that are more extensive, and therefore, more stringent than the requirements under federal standard provisions. The Discharger obtained enrollment for regulation under the General Order 2022-0103-DWQ. 6.2.5.3. Resource Recovery from Anaerobically Digestible Material. Some POTWs choose to accept organic material such as food waste, fats, oils, and grease into their anaerobic digesters for co-digestion to increase production of methane and other biogases for energy production and to prevent such materials from being discharged into the collection system, which could cause sanitary sewer overflows. The California Department of Resources Recycling and Recovery has proposed an exemption from requiring Process Facility/Transfer Station permits where this activity is regulated under waste discharge requirements or NPDES permits. The proposed exemption is restricted to anaerobically digestible material that has been prescreened, slurried, and processed/conveyed in a closed system to be co-digested with regular POTW sludge. The proposed exemption requires that a POTW develop standard operating procedures for the proper handling, processing, tracking, and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-51 management of the anaerobically digestible material before it is received by the POTW. Standard operating procedures are required for POTWs that accept hauled food waste, fats, oil, and grease for injection into anaerobic digesters. The development and implementation of standard operating procedures for management of these materials is intended to allow the California Department of Resources Recycling and Recovery to exempt this activity from separate and redundant permitting programs. If the POTW does not accept food waste, fats, oil, or grease for resource recovery purposes, it is not required to develop and implement standard operating procedures. 6.2.5.4. Biosolids. Provisions regarding sludge handling and disposal ensure that such activities will comply with all applicable regulations. 40 C.F.R. part 503 sets forth U.S. EPA’s final rule for the use and disposal of biosolids, or sewage sludge, and governs the final use or disposal of biosolids. The intent of this federal program is to ensure that sewage sludge is used or disposed of in a way that protects both human health and the environment. U.S. EPA’s regulations require that producers of sewage sludge meet certain reporting, handling, and disposal requirements. As the U.S. EPA has not delegated the authority to implement the sludge program to the State of California, the enforcement of sludge requirements that apply to the Discharger remains under U.S. EPA's jurisdiction at this time. U.S. EPA, not the Central Coast Water Board, will oversee compliance with 40 C.F.R. part 503. 6.2.5.5. Discharges of Stormwater. Discharges of stormwater from POTWs with a design capacity greater than 1.0 MGD are applicable for coverage under General State Water Board Order No. 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Dischargers of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.2.6. Other Special Provisions 6.2.6.1. Recycled Water Policy Salt/Nutrient Management Plan. This Order requires the Discharger to develop and implement a Salt/Nutrient Management Plan. This requirement is based on the Recycled Water Policy. 6.2.6.2. Climate Change Adaptation Program. On March 7, 2017, the State Water Board adopted a resolution in recognition of the challenges posed by climate change that requires a proactive approach to climate change in all State Water Board actions, including drinking water regulation, water quality protection, and financial assistance (Resolution 2017- 0012). The resolution lays the foundation for a response to climate change that is integrated into all State Water Board actions, by giving direction to the State Water Board divisions and encouraging coordination with the regional water quality control boards. This Order requires the Discharger to implement and submit a Climate Change Adaptation Program. The Central Coast Water Board is addressing the threats of climate change and flooding by including provisions CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-52 in new and reissued orders that ensure climate change mitigation and adaptation strategies are implemented. There is widespread scientific consensus that climate change is occurring and will continue at an accelerating rate into the future. Extreme weather events, including drought, high-intensity precipitation, flooding, and extreme heat have occurred through much of California in recent years and are projected to increase in frequency, extent, or intensity due to climate change. Climate change has the potential to impact discharging facilities through inundation, storm impacts, and erosion, increasing the risk of accidental discharge that results in discharge permit violations. These events have significant implications for wastewater treatment and operations, such as increased corrosion, deposition of solids, infiltration, overflows, inundation of facilities, impairment of treatment processes, and disruption of power or electrical components. Due to the long-term nature of these risks, there is a need to avoid piecemeal or reactionary adaptation and instead undertake proactive, long-term planning with consideration of various adaptation strategies that both keep facilities safe, maintain safe discharging practices, and avoid impacts to resources. A description of the actions taken by the Discharger are described in section 2.5 – Response to Climate Change of this Order. These requirements are consistent with 40 CFR section 122.41(e), requiring permittees to ensure compliance through proper operation and maintenance of facilities, including installation and operation of appropriate auxiliary and backup facilities, and they are authorized pursuant to Water Code section 13383. (In re the City of Oceanside, Fallbrook Public Utilities Dist. And the Southern California Alliance of Publicly Owned Treatment Works, State Water Board Order WQ 2021- 0005, February 12, 2021 at p. 26.) The Los Angeles Water Board understands that the cost of preparing such a plan could be significant (estimated cost range of $25,000-$60,000), but "the costs of ensuring resilient infrastructure to protect water quality against the effects of climate change is warranted." (Fallbrook, at p. 27.) 6.2.7. Compliance Schedules – Not Applicable 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS CWA section 308 and 40 C.F.R. sections 122.41(h), (j)-(l), 122.44(i), and 122.48 require that all NPDES permits specify monitoring and reporting requirements. Sections 13267 and 13383 of the California Water Code also authorize the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements related to discharges to navigable waters or publicly owned treatment works, with section 13267 being the specific statute authorizing all such activities pertaining to the State Water Board’s Water Quality Control Policy for Recycled Water. The MRP, Attachment E of this Order, establishes monitoring, reporting, and recordkeeping requirements that implement federal and state requirements. The following provides the rationale for the inclusion of the monitoring and reporting requirements contained in the MRP for this facility to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-53 ensure compliance with Order requirements to ensure protection of water quality and beneficial uses. The Central Coast Water Board has considered the cost and need for monitoring and reporting generally in this NPDES permit. The discharger has provided the Central Coast Water Board with an estimation of its monitoring and reporting costs here, which are $226,860 for five years. Although the costs are significant, the costs are reasonable considering the nature of the wastewater discharge and because they result in critical data required under the Clean Water Act and which are needed to evaluate water quality generally, the impacts of the discharges on human and aquatic and benthic health, and water quality specifically, and to ensure that beneficial uses are protected. The requirements are generally comparable to other inland dischargers in the region. 7.1. Influent Monitoring In addition to influent flow monitoring, monitoring for BOD 5 and TSS is required to determine compliance with the Order’s percent removal requirement for these pollutants and to assess plant performance. Influent monitoring requirements have been retained from the previous Order. 7.2. Effluent Monitoring Effluent monitoring is necessary to determine compliance with effluent limitations and evaluate compliance with applicable water quality objectives and criteria. Effluent monitoring requirements have been retained from the previous Order for Discharge Point 001, with some exceptions. Effluent monitoring for fecal coliform has been removed and replaced with E. coli monitoring to be consistent with the updated Bacteria Provisions. Effluent monitoring frequency has been increased in this Order to monthly for those pollutants with a reasonable potential to cause or contribute to an exceedance of a water quality standards and for which effluent limitations were established: mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, nitrite (as N), un- ionized ammonia, MBAS, total dissolved solids, sulfate, chloride, and sodium. Chronic toxicity monitoring has increased to monthly to reflect the requirements of the updated Toxicity Provisions. A quarterly effluent monitoring requirement has been established for hardness to assist with the next permit’s reasonable potential analysis. An annual effluent monitoring frequency has been established for results of the reasonable potential analysis and the 2019 Basin Plan objectives . 7.3. Whole Effluent Toxicity Testing Requirements Acute and chronic toxicity monitoring requirements and chronic toxicity effluent limitations have been established in this Order in accordance with the 2020 Toxicity Provisions in the ISWEBE Plan. An acute toxicity test is conducted over a short time period and measures mortality. A chronic toxicity test is conducted over a longer period of time and may measure mortality, reproduction, and growth. For this permit, chronic toxicity in the discharge was evaluated using U.S. EPA’s 2010 TST hypothesis testing approach and is expressed as “Pass” or “Fail” for the median CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-54 monthly summary results and “Pass” or “Fail” and “Percent Effect” for each individual acute and chronic toxicity result. The chronic toxicity effluent limitations protect the narrative WQO in the Basin Plan and comply with the requirement in the Toxicity Provisions to establish chronic effluent limitations for Facilities with permitted discharges greater than 5.0 MGD and a pretreatment program. This Order requires the Discharger to submit an updated TRE Work Plan submitted pursuant to Order No. R3-2014-0033 within 90 days of the effective date of the Order. The TRE Work Plan must describe steps the Discharger intends to follow if the effluent limitation for chronic toxicity is exceeded. If a routine acute and/or chronic toxicity test results in a “Fail” at the IWC, this Order requires the Discharger to conduct accelerated monitoring to determine the cause of the toxicity. A TRE is required when the Discharger has any combination of two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. In addition, if other information indicates toxicity (e.g., results of additional monitoring, fish kills, intermittent recurring toxicity, etc.), then the Central Coast Water Board may require a TRE. If a TRE is required, the Discharger is required to submit a detailed TRE Work Plan in accordance with U.S. EPA guidance which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharger will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TRE/TlE process in accordance with the submitted work plan if the results of toxicity testing exceed the effluent limitations for chronic toxicity. This Order retains annual acute toxicity monitoring requirements and establishes monthly chronic toxicity monitoring requirements based on the RPA determination for toxicity using the TST approach and the Toxicity Provisions. Refer to section 5 of the MRP (Attachment E). 7.4. Recycled Water Monitoring Recycled water monitoring is necessary to evaluate compliance with recycling specifications detailed in section 4.3 of this Order. 7.5. Receiving Water Monitoring 7.5.1. Surface Water Surface water receiving water requirements are necessary to evaluate compliance with water quality objectives, WQBELs, and the protection of beneficial uses. Surface water monitoring requirements have been retained from Order R3-2014-0033 for Discharge Point 001, with some changes in sampling frequency and additional constituents to monitor. Annual monitoring for CTR and title 22 pollutants has been included in this Order because it had not been required historically and is necessary to obtain the background (B) concentration data that will be used for the next permit’s reasonable potential analysis. Quarterly sampling of E.coli has been included in this Order to be consistent with CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-55 the statewide Bacteria Provisions. Sampling frequency for flow, turbidity, color, pH, dissolved oxygen, and temperature have been decreased from weekly to monthly due to personnel safety concerns at sampling locations in the creek. Monthly monitoring of these parameters will provide sufficient data of the receiving water. Quarterly monitoring of boron and monthly monitoring of TDS, chloride, sodium, and sulfate have been included in this Order to provide an understanding of salts concentrations in the receiving water. The addition of quarterly monitoring of hardness in this Order will assist with the next permit’s reasonable potential analysis. 7.5.2. Groundwater Consistent with the previous permit, groundwater monitoring requirements have not been included. 7.6. Other Monitoring Requirements 7.6.1. Discharge Monitoring Report-Quality Assurance (DMR-QA) Study Program Under the authority of section 308 of the CWA (33 U.S.C. 1318), U.S. EPA requires major and selected minor dischargers under the NPDES Program to participate in the annual DMR-QA Study Program. The DMR-QA Study Program evaluates the analytical ability of laboratories that routinely perform or support self-monitoring analyses required by NPDES permits. There are two options to satisfy the requirements of the DMR-QA Study Program: (1) The Discharger can obtain and analyze a DMR-QA sample as part of the DMR-QA Study; or (2) Per the waiver issued by U.S. EPA to the State Water Board, the Discharger can submit the results of the most recent Water Pollution Performance Evaluation Study from its own laboratories or its contract laboratories. A Water Pollution Performance Evaluation Study is similar to the DMR-QA Study. Thus, it also evaluates a laboratory’s ability to analyze wastewater samples to produce quality data that ensure the integrity of the NPDES Program. The Discharger shall ensure that the results of the DMR-QA Study or the results of the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board. The State Water Board’s Quality Assurance Program Officer will send the DMR-QA Study results or the results of the most recent Water Pollution Performance Evaluation Study to U.S. EPA’s DMR-QA Coordinator and Quality Assurance Manager. 7.6.2. Annual Volumetric Reporting of Wastewater and Recycled Water To establish a realistic estimate of statewide recycled water use and potential for increased recycled water use statewide, the Recycled Water Policy requires Dischargers to report the volume of treated wastewater and recycled water. The annual report will meet implementation needs of the Recycled Water Policy and fill data gaps for additional statewide water planning efforts. The burden and cost of preparing the report is reasonable and consistent with the interest of the state in maintaining water quality and developing alternative water supplies to increase water resiliency. The Discharger shall ensure that all volumetric reporting requirements from this Order are submitted in electronic format via the State CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-56 Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. The State Water Board will evaluate progress towards the recycled water goals in the Recycled Water Policy and evaluate the need to update the recycled water goals in the future based on consistent statewide data. 7.6.3. Biosolids/Sludge Monitoring Biosolids monitoring shall be reported in the annual report in accordance with 40 C.F.R. 503. Biosolids monitoring requirements have been retained from the previous Order. 7.6.4. Pretreatment Monitoring Pretreatment monitoring shall be reported in the annual report in accordance with requirements in 40 C.F.R. 403.8. Pretreatment monitoring requirements have been retained from the previous Order. 7.6.5. Salt and Nutrient Management Plan Reporting Salt and Nutrient Management Plan reporting requirements have been retained in this Order to help identify and reduce salt and nutrient loading in effluent. This salt/nutrient management report shall be included as a separate report from the annual report. 7.6.6. Discharge to Evaporation Ponds Reports of discharge to and from the Facility’s evaporation ponds are required pursuant to California Water Code section 13383. Any costs incurred with this reporting are expected to be minimal. The reporting is necessary to ensure compliance with the provisions of this Order, inform follow-up actions in the event of noncompliance with the provisions of this Order, and to protect human health and water quality. 8. CONSIDERATION OF NEED TO PREVENT NUISANCE AND WATER CODE SECTION 13241 FACTORS The requirements set forth in subsections 2.4 and 4.3 of this Order are included to implement state law only. These requirements are not required or authorized under the federal CWA; consequently, violations of these requirements are not subject to the enforcement remedies that are available for NPDES violations. As required by Water Code section 13263, the Central Coast Water Board has considered the need to prevent nuisance and the factors listed in Water Code section 13241 in establishing the state law provisions/requirements. The Central Coast Water Board finds, on balance, that the state law requirements in this Order are reasonably necessary to prevent nuisance and to protect beneficial uses identified in the Basin Plan, and the section 13241 factors are not sufficient to justify failing to protect those beneficial uses. 8.1. Need to prevent pollution or nuisance In establishing effluent limitations in this Order, the Central Coast Water Board has considered state law requirements to prevent pollution or nuisance as defined in CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-57 section 13050, subdivisions (l) and (m), of the Water Code. The requirements in this Order, including those set forth in subsections 2.4 and 4.3, will prevent pollution and nuisance. 8.2. Past, present, and probable future beneficial uses of water Chapter 2 of the Basin Plan identifies designated beneficial uses for water bodies in the Central Coast Region. Beneficial uses of water relevant to this Order are also identified above in sections 3.3.1 of this Fact Sheet. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order, including those set forth in sections 2.4 and 4.3 of this Order. Accordingly, the requirements herein protect and augment the past, present and probable future beneficial uses of the water. 8.3. Environmental characteristics of the hydrographic unit under consideration, including the quality of water available thereto The environmental characteristics of this watershed are discussed in the Basin Plan, as well as available in State of the Watershed reports and the State’s CWA Section 303(d) List of impaired waters. The environmental characteristics of the hydrographic unit, including the quality of available recycled water that may be produced as a result of this Order will be improved by compliance with the requirements of this Order. 8.4. Water quality conditions that could reasonably be achieved through the coordinated control of all factors which affect water quality in the area The water quality standards necessary to protect beneficial uses of San Luis Obispo Creek Sub-Basin of the Estero Bay Drainage Basin can reasonably be achieved through the coordinated control of all factors that affect water quality in the area, including the conservation of water and/or the production of recycled water authorized by this Order. For example, the water quality in the watershed and/or groundwater basin could be improved through the addition or use of recycled water authorized by this Order, which meets title 22 standards. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order. 8.5 Economic Considerations The Permittee presented evidence regarding cost of monitoring but did not present additional evidence concerning other economic considerations related to this Order, such as the benefits of producing recycled water and benefits resulting from protection of beneficial uses of San Luis Obispo Creek. The Central Coast Water Board has considered the economic impact of requiring certain provisions pursuant to state law, including the costs of conducting feasibility studies for recycling, conservation, and climate change. Any additional costs associated with producing any study are reasonably necessary to prevent nuisance and protect beneficial uses identified in the Basin Plan and to improve the water supply resiliency. The failure to consider conservation or recycled water could result in the loss of, or impacts to, beneficial uses, which would have a detrimental economic impact, particularly given the effects on beneficial uses and supplies of water from the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-58 drought and climate change. Economic considerations related to costs of compliance are therefore not sufficient, in the Central Coast Water Board’s determination, to justify failing to prevent nuisance and protect beneficial uses. 8.6 The need for developing housing within the region The Central Coast Water Board does not anticipate that these state law requirements will adversely impact the need for housing in the area. To the contrary, this Order helps address the need for housing by controlling pollutants in discharges and by allowing the reuse and exportation of recycled water for use in the area. Both of these things will improve the quality of local surface and groundwater, as well as water supply generally. This may in turn increase the region’s capacity to support continued housing development. Therefore, the potential for developing housing in the area will be facilitated by the conservation of water, or reuse or the production of recycled water, under this permit. 8.7. Need to develop and use recycled water The State Water Board’s Recycled Water Policy requires the Central Coast Water Board to encourage the use of recycled water. In addition, as discussed immediately above, a need to develop and use recycled water exists within the region, especially during times of drought. To encourage recycling, the Permittee is required by this Order to continue to explore the feasibility of recycling to maximize the beneficial reuse of tertiary treated effluent and to report on its recycled water production and use. The Discharger shall submit an update to this feasibility investigation as part of the submittal of the Report of Waste Discharge (ROWD) for the next permit renewal. 9. PUBLIC PARTICIPATION The Central Coast Water Board is considering the issuance of WDRs that will serve as an NPDES permit for the City of San Luis Obispo Water Resource Recovery Facility. As a step in the WDR adoption process, Central Coast Water Board staff developed tentative WDRs and encourages public participation in the WDR adoption process. 9.1. Notification of Interested Persons The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provid ed an opportunity to submit written comments and recommendations. Notification was provided via the Central Coast Water Board’s website and e-mail subscription service. The public can access the agenda and any changes in dates and locations through the Central Coast Water Board’s website at http://www.waterboards.ca.gov/centralcoast/ CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-59 9.2. Written Comments Interested persons were invited to submit written comments on December 14, 2023, concerning these tentative WDRs. To be fully responded to by staff and considered by the Central Coast Water Board, the written comments were due at the Central Coast Water Board office by 5:00 p.m. on January 16, 2024. 9.3. Public Hearing The Central Coast Water Board held a public hearing on the tentative WDRs during its regular Board meeting on the following date and time and at the following location: Date: June 20-21, 2024 Time: 9:00 am-5:00 pm Location: Link to video and teleconference were provided at https://www.waterboards.ca.gov/centralcoast/board_info/age ndas/2024/2024_agendas.html Interested persons were invited to attend. At the public hearing, the Central Coast Water Board heard testimony pertinent to the discharge, WDRs, and permit. For accuracy of the record, important testimony was requested in writing. 9.4. Reconsideration of Waste Discharge Requirements Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Board must receive the petition by 5:00 p.m., within 30 calendar days of the date of adoption of this Order at the following address, except that if the thirtieth day following the date of this Order falls on a Saturday, Sunday, or state holiday, the petition must be received by the State Water Board by 5:00 p.m. on the next business day: State Water Resources Control Board Office of Chief Counsel P.O. Box 100, 1001 I Street Sacramento, CA 95812-0100 Or by email at waterqualitypetitions@waterboards.ca.gov For instructions on how to file a petition for review, see the State Water Board’s website on instructions for filing water quality petitions at: https://www.waterboards.ca.gov/public_notices/petitions/water_quality/wqpetition_i nstr.shtml. 9.5. Information and Copying The Report of Waste Discharge, other supporting documents, and comments received are on file and may be inspected at the address above at any time CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-60 between 8:00 a.m. and 5:00 p.m., Monday through Friday. Copying of documents may be arranged through the Central Coast Water Board by calling (805) 549- 3147. 9.6. Register of Interested Persons Any person interested in being placed on the mailing list for information regarding the WDRs and NPDES permit should contact the Central Coast Water Board, reference this facility, and provide a name, address, and phone number. 9.7. Additional Information Requests for additional information or questions regarding this order should be directed to Sarah Crable at (805) 549-3706 or Sarah.Crable@waterboards.ca.gov or Arwen Wyatt-Mair at (805) 542-4695 or Arwen.Wyattmair@waterboards.ca.gov. STATE OF CALIFORNIA CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401 TIME SCHEDULE ORDER R3-2024-0021 REQUIRING THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY TO COMPLY WITH REQUIREMENTS PRESCRIBED IN NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT CA0049224, ORDER R3-2024-0001 The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 1.The City of San Luis Obispo (Discharger) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (Facility), a publicly owned treatment works (POTW). The Facility is located at 35 Prado Road, San Luis Obispo, San Luis Obispo County. 2.Treatment at the Facility currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four Modified Ludzack-Ettinger (MLE) bioreactors, hollowfiber membranes, and ultraviolet (UV) disinfection. The biosolids handling unit consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. 3.On June 20, 2024, the Central Coast Water Board adopted Waste Discharge Requirements Order R3-2024-0001, National Pollutant Discharge Elimination System (NPDES) Permit CA0049224. Order R3-2024-0001 regulates the discharge of tertiary treated effluent from the Facility to San Luis Obispo Creek, a water of the United States, located within the Estero Bay Hydrologic Unit. The effective date of Order R3- 2024-0001 is September 1, 2024. 4.Analysis of the Discharger’s effluent monitoring data from December 2014 through December 2022 found that the Discharger’s effluent had a reasonable potential to cause or contribute to exceedances of water quality objectives for total dissolved solids (TDS), chloride, sodium, sulfate, and molybdenum, and therefore warranted the establishment of effluent limitations for those parameters. 5.Order R3-2024-0001 prescribes the following new effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum. TSO R3-2024-0021 -2- September 1, 2024 Table 1: Final effluent limitations in Order R3-2024-0001 1Compliance is determined using a 12-month running mean. NEED FOR TIME SCHEDULE ORDER AND REGULATORY REQUIREMENTS 6.The Discharger is unable to consistently comply with the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum, which were not effluent limits in the prior permit and are new to Order R3-2024-0001. In its January 11, 2024 comment letter on draft Order R3-2024-0001, the Discharger asked the Central Coast Water Board to include an in-permit compliance schedule to allow the Discharger time to develop and implement improvements to comply with the new effluent limits. 7.State Water Resources Control Board Resolution 2008-0025, Policy for Compliance Schedules in National Pollutant Discharge Elimination System Permits (Compliance Schedule Policy), was adopted on April 15, 2008. The Policy provides that in-permit compliance schedules should only be granted when additional time is needed to complete significant compliance actions to comply with new permit limitations implementing new, revised, or newly interpreted water quality objectives or criteria in water quality standards. The Compliance Schedule Policy defines the term “new, revised or newly interpreted water quality standard” to be standards adopted by the Central Coast Water Board after September 25, 1995. (Compliance Schedule Policy, p. 3, paragraph 1 subd. (d).) The Compliance Schedule Policy defines the term “newly interpreted water quality objective or criterion in a water quality standard,” as meaning: a narrative water quality objective or criterion that, when interpreted during NPDES permit development (using appropriate scientific information and consistent with state and federal law) to determine the permit limitations necessary to implement the objective, results in a numeric permit limitation more stringent than the limit in the prior NPDES permit issued to the discharger. Newly interpreted water quality objective or criterion in a water quality standard also includes a numeric or narrative water quality objective or criterion that is implemented with a permit limitation with which the discharger cannot comply because the pollutant was newly detected in the discharger’s effluent due to new analytical techniques that were developed after the prior permit was issued. (Id., p. 3, paragraph 1 subd. (e).) 8.The Water Quality Control Plan for the Central Coastal Basin (Basin Plan) includes numeric water quality objectives for TDS, chloride, sodium, sulfate, and molybdenum. Basin Plan Table 3-5 includes numeric mean surface water quality objectives for TDS, chloride, sodium, and sulfate specific to San Luis Obispo Creek. Table 3-2 includes the numeric water quality objective for molybdenum for waters with the agricultural supply beneficial use, which applies to San Luis Obispo Creek. Parameter Units Average Annual1 Average Monthly TDS mg/L 650 Chloride mg/L 100 Sodium mg/L 50 Sulfate mg/L 100 Molybdenum mg/L 0.01 TSO R3-2024-0021 -3- September 1, 2024 These numeric water quality objectives were used in the analyses that found the Facility had reasonable potential to cause or contribute to exceedances of water quality objectives. These objectives have been part of the Basin Plan since at least 1994. 9.The Discharger is not eligible for an in-permit compliance schedule because the water quality objectives used to establish the new effluent limitations for TDS, chloride, sodium, and sulfate in Order R3-2024-0001 were not new, revised, or newly interpreted water quality standards as that term is defined in the Compliance Schedule Policy. Similarly, the Discharger is not eligible for an in-permit compliance schedule for molybdenum because the water quality objective used to establish the new effluent limitation for molybdenum in Order R3-2024-0001 was not a new, revised, or newly interpreted water quality standard as that term is defined in the Compliance Schedule Policy. Although molybdenum is newly detected in the Discharger’s effluent through monitoring requirements established in the Discharger’s previous NPDES permit, Order R3-2014-0033, the analytical techniques were developed long before the prior permit was issued. 10.Considering the foregoing analysis, a time schedule order, issued pursuant to California Water Code (Water Code) sections 13300 and 13385(j)(3), is the appropriate mechanism to allow the Discharger additional time to comply with its effluent limitations in Order R3-2024-0001. 11.Section 13300 of the Water Code states: “Whenever a regional board finds that a discharge of waste is taking place or threatening to take place that violates or will violate requirements prescribed by the regional board, or the state board, or that the waste collection, treatment, or disposal facilities of a permittee are approaching capacity, the board may require the permittee to submit for approval of the board, with such modifications as it may deem necessary, a detailed time schedule of specific actions the permittee shall take in order to correct or prevent a violation of requirements.” 12.Water Code section 13385, subdivisions (h) and (i), require the Central Coast Water Board to impose mandatory minimum penalties upon dischargers that violate certain effluent limitations. Section 13385(j)(3)(A) exempts violations of an effluent limitation from mandatory minimum penalties "where the waste discharge is in compliance with … a time schedule order issued pursuant to Section 13300, if all of the [specified] requirements are met." (emphasis added). 13.Pursuant to Water Code section 13385 subdivision (j)(3)(B)(i), the Central Coast Water Board finds that, based on effluent monitoring data, the Discharger is not able to consistently comply with the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum in Order R3-2024-0001 while new or modified control measures are implemented to increase pollutant removal efficiency or reduce the amount of these pollutants the facility receives. The effluent limitations for these pollutants are new requirements for the Discharger, and a time schedule order will allow the Discharger time to assess discharges to the collection system, collect data, perform studies, and develop additional pretreatment and control options for molybdenum and high-concentration TDS, chloride, sodium, and sulfate dischargers within the city. In addition, the new or modified control measures cannot be designed, installed, and put into operation within 30 calendar days. TSO R3-2024-0021 -4- September 1, 2024 14.The Discharger intends to carry out source control measures by implementing a pollution prevention plan, performing a source identification study, and performing a pretreatment program local limits study. During these efforts, the Discharger may be temporarily unable to comply with the Order R3-2024-0001 final effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum, and interim effluent limits are necessary. The period of this time schedule order is September 1, 2024, through August 31, 2029. 15.During the period of the time schedule order, the Discharger will continue to operate and discharge under all the limitations specified in Order R3-2024-0001 except for TDS, chloride, sodium, sulfate, and molybdenum. The Discharger will continue to report on all parameters as specified in Order R3-2024-0001. 16.Pursuant to Water Code section 13223, the Central Coast Water Board has delegated to its Executive Officer the authority to issue a time schedule order pursuant to Water Code section 13300. 17.Water Code section 13383 authorizes the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements for any person who owns or operates a publicly owned treatment works. In accordance with 40 C.F.R. sections 25.5 and 124.10 subd. (b)(1) and Water Code section 13378, the Central Coast Water Board publicly noticed this time schedule order from March 12, 2024 through April 11, 2024. No public comments were received. 18.Issuance of this time schedule order is exempt from provisions of the California Environmental Quality Act (Pub. Resources Code, section 21000 et seq.) (CEQA) pursuant to Water Code section 13389 because the adoption or modification of an NPDES permit for an existing source is statutorily exempt from CEQA, and this time schedule order only serves to implement an NPDES permit. (Pacific Water Conditioning Ass’n, Inc. v. City Council of City of Riverside (1977) 73 Cal. App. 3d 546, 555-556). Furthermore, this enforcement action is taken for the protection of the environment and as such is exempt from CEQA in accordance with section 15321, chapter 3, title 14, California Code of Regulations. MANDATORY MINIMUM PENALTIES 19.Pursuant to Water Code section 13385(j)(3), violations of the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum in Order R3-2024-0001 are not subject to Water Code section 13385 subdivisions (h) and (i) mandatory minimum penalties, provided the Discharger complies with all the requirements of this time schedule order and all the following conditions are met: a. The time schedule order specifies the actions that the Discharger is required to take in order to correct the violations that would otherwise be subject to subdivisions (h) and (i). b. The Central Coast Water Board finds that the Discharger is not able to consistently comply with one or more of the effluent limitations established in the waste discharge requirements applicable to the waste discharge for one of the reasons described in Water Code section 13385(j)(3)(B)(i)-(iv) (see Paragraph 12, supra). TSO R3-2024-0021 -5- September 1, 2024 c.The Central Coast Water Board establishes a time schedule for bringing the waste discharge into compliance with the final effluent limitation that is as short as possible and does not exceed five years in length. d.For time schedules that exceed one year from the effective date of the time schedule order, the schedule shall include interim requirements and the dates for their achievement. The interim requirements shall include both of the following: i.Effluent limitations for the pollutant or pollutants of concern. ii.Actions and milestones leading to compliance with the effluent limitation. e.The Discharger has prepared and is implementing in a timely and proper manner or is required by the Central Coast Water Board to prepare and implement a pollution prevention plan pursuant to CWC section 13263.3. This time schedule order requires the Discharger to prepare, implement, and submit a pollution prevention plan for TDS, chloride, sodium, sulfate, and molybdenum. This time schedule order satisfies the above conditions a-e. 20.This time schedule order requires the Discharger to comply with a time schedule by August 31, 2029, that will allow the Discharger to achieve full compliance with TDS, chloride, sodium, sulfate, and molybdenum final effluent limitations in Order R3-2024- 0001. 21.This time schedule order includes performance-based interim effluent limitations that are based on the 97.22 percentile for results measured from 2015 to 2023 for TDS, chloride, sodium sulfate, and molybdenum as shown in Table 3. 22.The Central Coast Water Board expects that the Discharger can maintain compliance with the interim effluent limitations included in this time schedule order. Interim effluent limitations are established when compliance with the final effluent limitations cannot be achieved by the existing Facility. Discharge of pollutants in concentrations in excess of the final limitations in the permit, but in compliance with the interim effluent limitations, can significantly degrade water quality and adversely affect the beneficial uses of the receiving stream on a long-term basis. The interim effluent limitations, however, establish an enforceable ceiling value until compliance with the final effluent limitations can be achieved. 23.If an interim effluent limit established in this time schedule order for TDS, chloride, sodium, sulfate, or molybdenum is exceeded, then the Discharger is subject to a mandatory minimum penalty for that particular exceedance as the Discharger will no longer meet the exemption in Water Code section 13385, subdivision (j)(3). IT IS HEREBY ORDERED, pursuant to California Water Code sections 13300 and 13383 and to ensure compliance with the requirements of adopted Waste Discharge Requirements Order R3-2024-0001, NPDES Permit CA0049224: 1.The Discharger shall comply with the following schedule of actions: TSO R3-2024-0021 -6- September 1, 2024 Table 2. Compliance Schedule for Total Dissolved Solids, Chloride, Sodium, Sulfate, Molybdenum (Starting September 1, 2024) Required Actions Compliance Due Dates Submit semi-annual progress and sampling results of TDS, chloride, sodium, sulfate, and molybdenum in Facility influent and effluent. Reports shall include but not be limited to: ·Discussion of overall progress in implementing the requirements of this TSO and achieving full compliance with Order R3-2024-0001 ·Results of source identification efforts and potential modifications to local limits or other pretreatment program actions ·Evaluation of compliance with final effluent limitations ·Update the Pollution Prevention Plan (PPP) section with descriptions of actions to be taken in the upcoming year beginning with the August 15, 2025 report and annually thereafter. 1st Semi-annual Report (Jul-Dec) – due by Feb 15 2nd Semi-annual Report (Jan-Jun) – due by Aug 15 Submit Pollution Prevention Plan (PPP) for TDS, chloride, sodium, sulfate, and molybdenum. Requirements for the PPP are set forth below. Submit an annual update to the PPP as a section in the semi-annual progress report describing planned actions for the upcoming year and discussing results from the previous year. PPP for calendar year 2025 due January 15, 2025 Updated PPP for 2026 due Aug 15, 2025 Updated PPP for 2027 due Aug 15, 2026 Updated PPP for 2028 due Aug 15, 2027 Updated PPP for 2029 due Aug 15, 2028 Submit Source Identification Study plan for review and approval by the Executive Officer. Requirements for the Source Identification Study are set forth below. January 15, 2025 Initiate Source Identification Study May 31, 2025 Submit Local Limits Study plan for review and approval by the Executive Officer. Requirements for the Local Limits Study are set forth below. May 1, 2026 Submit Source Identification Study results. Nov 1, 2026 Initiate Local Limits Study. Nov 1, 2026 TSO R3-2024-0021 -7- September 1, 2024 Required Actions Compliance Due Dates Submit draft Local Limits Study report, including proposed changes to local limits. Nov 1, 2027 Submit final Local Limits Study report.May 1, 2028 Achieve full compliance with final effluent limitations in Order R3-2024-0001. August 31, 2029 Pollution Prevention Plan (PPP): The PPP is an iterative plan that the Discharger will update and submit on an annual basis. The annual PPP must include the following deliverables: a.A description of new or modified methods that will be used to prevent or reduce the amount of TDS, chloride, sodium, sulfate, and molybdenum in the facility's influent and effluent during the upcoming year. Pollution prevention methods may include application and enforcement of local limits to industrial or commercial dischargers, public education and outreach, upgrades or changes to the Facility’s treatment system, or other innovative and alternative approaches to reduce discharges of TDS, chloride, sodium, sulfate, and molybdenum to and from the facility. b.An estimate of load reductions that may be attained through the methods identified above. c.A plan for monitoring and assessing the results of the pollution prevention plan. d.A discussion of the pollution prevention methods used during the previous year. e.An estimate of the load reductions that were attained during the previous year. f.Once completed, a summary of the findings of the Source Identification Study, including the monitoring results and all identified sources of TDS, chloride, sodium, sulfate, and molybdenum to and from the Facility. g.Once completed, a discussion of the findings of the Local Limits Study and a description of how the Facility’s pretreatment program will be modified. Source Identification Study: The Source Identification Study must, at a minimum, include a sampling plan consistent with the guidance in Chapter 4 of EPA’s Local Limits Development Guidance.1 The sampling must occur for a minimum of one year and must be carried out in such a manner that it is spatially and temporally representative. The Source Identification Study may include additional source identification or monitoring that the Discharger identifies as being useful in understanding and reducing all sources of pollutants in the Facility’s influent and effluent. Local Limits Study: The Local Limits Study must include a detailed re-evaluation of local limits, as described in EPA’s Local Limits Development Guidance. The Local Limits Study will use the results of the Source Identification Study to calculate or recalculate maximum allowable headworks loadings (MAHLs) for TDS, chloride, 1 https://www3.epa.gov/npdes/pubs/final_local_limits_guidance.pdf TSO R3-2024-0021 -8- September 1, 2024 sodium, sulfate, molybdenum, and any other pollutants identified as requiring further evaluation. The Discharger must use the MAHLs to develop or update local limits. 2.If the Discharger is unable to perform any activity or submit any documentation in compliance with the deadlines set forth in Table 2, the Discharger may request, in writing, an extension of the time. The extension request shall include justification for the delay and shall be submitted at least thirty days prior to the respective deadline to be considered complete and timely. 3.The following interim effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum shall be effective upon the effective date of this time schedule order and shall apply in lieu of all final effluent limitations for those pollutants in Order R3- 2024-0001. The Discharger shall maintain compliance with the following interim effluent limitations through August 31, 2029, or until the Discharger is able to come into compliance with the final effluent limitations, whichever is sooner. Table 3: Interim effluent limitations 1Compliance is determined using a 12-month running mean. 4.All reports shall be submitted under Discharger signed/certified cover letter to the California Integrated Water Quality System (CIWQS). The Executive Officer may require revisions to the form or types of data and information reported. 5.All reports required by this time schedule order shall be signed by either a principal executive officer or ranking elected official, or by a duly authorized representative of that person. A person is a duly authorized representative only if: a.The authorization is made in writing by a person described above; b.The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the owner of the regulated facility. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.); and c.The written authorization is submitted to the Central Coast Water Board. 6.Any person signing a report required by this time schedule order shall make the following certification: “I certify under penalty of perjury that this document and all attachments were prepared by me, or under my direction or supervision, following a system designed to ensure that qualified personnel properly gather and evaluate the information submitted. To the best of my knowledge and belief, this document and all attachments are true, accurate, and complete. I am aware that there are significant Parameter Units Average Annual1 Average Monthly TDS mg/L 988 Chloride mg/L 196 Sodium mg/L 196 Sulfate mg/L 157 Molybdenum mg/L 0.024 TSO R3-2024-0021 -9- September 1, 2024 penalties for submitting false information, including the possibility of fine and imprisonment.” 7.If, in the opinion of the Executive Officer, the Discharger fails to comply with any provisions of this time schedule order or fails to consistently demonstrate substantive progress towards achieving full compliance with effluent limitations in Order R3-2024- 0001, the Executive Officer may terminate this time schedule order. In that case, or if compliance with the final effluent limitations for TDS, chloride, sodium, sulfate, or molybdenum in Order R3-2024-0001 is not achieved by the full compliance dates shown above in Table 2 or the Discharger has not received an extension according to Provision 2 above, the Discharger will not be exempt from the mandatory minimum penalties for violation of those effluent limitations and may also be subject to issuance of a cease and desist order in accordance with Water Code section 13301. The Central Coast Water Board reserves its right to take any enforcement action authorized by law. 8.During the effective period of this time schedule order, the Discharger shall comply with all provisions of Order R3-2024-0001, as renewed or revised, that are not in conflict with this time schedule order. If, in the opinion of the Executive Officer, the Discharger fails to comply with the provisions of this order, the Executive Officer may refer this matter to the Attorney General for judicial enforcement, may issue a complaint for administrative civil liability, or may take other enforcement actions. Failure to comply with this order may result in the assessment of administrative civil liability of up to $10,000 per violation, per day, depending on the violation, pursuant to the Water Code, including sections 13350 and 13385. The Central Coast Water Board reserves its right to take any enforcement actions authorized by law. Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Resources Control Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Resources Control Board must receive the petition by 5:00 p.m., 30 days after the date of the order, except that if the thirtieth day following the date of the order falls on a Saturday, Sunday, or state holiday, the petition must be received by 5:00 p.m. on the next business day. Copies of the law and regulations applicable to filing petitions may be found on the internet at: http://www.waterboards.ca.gov/public_notices/petitions/water_quality, or will be provided upon request. This Order is effective on September 1, 2024. The Executive Officer may modify the time schedule in this order to permit a specified task or tasks to be completed at later dates if the Discharger demonstrates and the Executive Officer determines that the delay was beyond the reasonable control of the Discharger to avoid. ORDERED BY ___ Ryan E. Lodge, Executive Officer R:\RB3\Shared\NPDES\Facilities\San Luis Obispo\San Luis Obispo\TSO R3-2024- 0021\Draft TSO\tso_slo_R3-2024-0021.docx Place ID: 255380 28 From:Anderson, Matt Sent:Wednesday, October 22, 2025 8:03 AM To:Tyler Lee Subject:FW: Change in Effluent Monitoring and Reporting and Toxicity Sensitivity Screening Update Attachments:Order R3-2024-0001 (1).pdf; EFF-001 Export 24-25.xlsx From: Anderson, Matt Sent: Thursday, September 4, 2025 2:30 PM To: Crable, Sarah@Waterboards <sarah.crable@waterboards.ca.gov> Cc: Lehman, Chris <clehman@slocity.org>; McGrath, Patrick <pmcgrath@slocity.org>; Parsons, Patrice <pparsons@slocity.org>; Chen, Bryan <BChen@slocity.org>; Duncan, Tanner <tduncan@slocity.org>; Rose, Jill <jrose@slocity.org> Subject: Change in Effluent Monitoring and Reporting and Toxicity Sensitivity Screening Update Good afternoon Sarah, I hope all is well this Tuesday. Per Order R3-2024-0001, Attachment E, page E-8, “If no exceedances of the effluent limitation occur for a minimum of 12 consecutive months of monitoring then the frequency of monitoring shall be reduced to quarterly. Subsequently, if an exceedance of the effluent limitation occurs during quarterly monitoring, the monitoring frequency shall return to monthly. The Discharger must notify the Central Coast Water Board of the change in monitoring frequency.” The City of San Luis Obispo’s Water Resource Recovery facility has had 12 consecutive months of compliance and has not exceeded effluent limits for MBAS, methylene chloride, chloroform, and pentachlorophenol. We will adjust our monitoring schedule this month, and will resume sampling MBAS, methylene chloride, chloroform, and pentachlorophenol on a quarterly basis beginning October 2025. The Water Resource Recovery Facility will resume toxicity sensitivity screening on Wednesday 9/17/2025. Please call or email me with any questions. 29 30 Matt Anderson Laboratory Manager Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 A B C D E F G 8914 1649 6275 1763 1399 2193 EFF-001 (C) MBAS EFF-001 (C) Methylene Chloride EFF-001 (C) Chloroform EFF-001 (C) Pentachlorophenol EFF-001 (C) Chlorodibromomethane EFF-001 (C) Dichlorobromomethane Date mg/L ug/L ug/L ug/L ppb ppb 9/3/2024 0.10 ND ND ND ND ND 10/15/2024 ND ND 0.8 ND ND ND 11/5/2024 0.16 ND 0.6 ND 0.90 ND 12/3/2024 ND ND ND ND ND ND 1/7/2025 ND ND ND ND ND ND 2/4/2025 0.11 ND 1.0 ND ND ND 3/4/2025 ND ND 3.0 ND ND 0.90 4/1/2025 ND ND 2.0 ND ND ND 5/6/2025 ND ND ND ND ND ND 6/4/2025 ND ND ND ND ND ND 7/1/2025 ND ND 0.9 ND ND ND 8/1/2025 ND ND ND ND ND ND Eff Limit 0.2 4.7 60.0 0.28 0.40 0.56 CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101, San Luis Obispo, California 93401 Phone (805) 549-3147 Fax (805) 543-0397 Central Coast Regional Water Quality Control Board (http://www.waterboards.ca.gov/centralcoast) ORDER R3-2024-0001 NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT NUMBER CA0049224 WASTE DISCHARGE REQUIREMENTS FOR THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY The following Discharger is subject to waste discharge requirements set forth in this Order: Discharger City of San Luis Obispo Name of Facility Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Table 1. Discharge Location Discharge Point Effluent Description Discharge Point Latitude (North) Discharge Point Longitude (West) Receiving Water 001 Tertiary treated domestic wastewater 35.244307° 120.680618° San Luis Obispo Creek 002 Disinfected Tertiary Recycled Municipal Wastewater - - Reclamation Use This Order was adopted on: June 20, 2024 This Order shall become effective on: September 1, 2024 This Order shall expire on: August 31, 2029 The Discharger shall file a Report of Waste Discharge as an application for reissuance of waste discharge requirements in accordance with title 23, California Code of Regulations and an application for reissuance of a National Pollutant Discharge CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 2 Elimination System permit no later than 180 days prior to the Order expiration date. The U.S. Environmental Protection Agency and the California Regional Water Quality Control Board, Central Coast Region have classified this discharge as follows: Major discharge. I, Ryan E. Lodge, Executive Officer, do hereby certify that this Order with all attachments is a full, true, and correct copy of an order adopted by the California Regional Water Quality Control Board, Central Coast Region on the date indicated above. Ryan E. Lodge, Executive Officer CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 3 TABLE OF CONTENTS 1. FACILITY INFORMATION .......................................................................................... 4 2. FINDINGS ................................................................................................................... 4 3. DISCHARGE PROHIBITIONS .................................................................................... 7 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS ................................. 7 4.1. Effluent Limitations – Discharge Point 001 ........................................................ 7 4.2. Land Discharge Specifications – Not Applicable ............................................. 11 4.3. Recycling Specifications – Discharge Point 002 ............................................. 11 5. RECEIVING WATER LIMITATIONS ......................................................................... 12 5.1. Surface Water Limitations ............................................................................... 12 5.2. Groundwater Limitations ................................................................................. 16 6. PROVISIONS ............................................................................................................ 17 6.1. Standard Provisions ........................................................................................ 17 6.2. Monitoring and Reporting Program (MRP) Requirements ............................... 17 6.3. Special Provisions ........................................................................................... 17 7. COMPLIANCE DETERMINATION ............................................................................ 23 TABLE OF TABLES Table 1. Discharge Location ............................................................................................ 1 Table 2. Effluent Limitations at Discharge Point 001 ....................................................... 8 Table 3. Organic Substances Water Quality Criteria ..................................................... 14 Table 4. Hardness Dependent Metals Criteria .............................................................. 15 Table 5. Annual Mean Surface Water Quality Objectives .............................................. 15 Table 6. Groundwater Objectives .................................................................................. 17 TABLE OF ATTACHMENTS ATTACHMENT A – DEFINITIONS ...............................................................................A-1 ATTACHMENT B – MAP ..............................................................................................B-1 ATTACHMENT C – FLOW SCHEMATIC .................................................................... C-1 ATTACHMENT D – STANDARD PROVISIONS ......................................................... D-1 ATTACHMENT E – MONITORING AND REPORTING PROGRAM ............................E-1 ATTACHMENT F – FACT SHEET ............................................................................... F-1 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 4 1. FACILITY INFORMATION Information describing the City of San Luis Obispo (Discharger) Water Resource Recovery Facility (Facility) is summarized on the cover page and in sections 1 and 2 of the Fact Sheet (Attachment F). Section 1 of the Fact Sheet also includes information regarding the Facility’s permit application. 2. FINDINGS The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 2.1. Legal Authorities. This Order serves as waste discharge requirements (WDRs) pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA) and implementing regulations adopted by the United States Environmental Protection Agency (U.S. EPA) and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as a National Pollutant Discharge Elimination System (NPDES) permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1 subject to the WDRs in this Order. 2.2. Background and Rationale for Requirements. The Central Coast Water Board developed the requirements in this Order based on information submitted as part of the application, through monitoring and reporting programs, and other available information. The Fact Sheet (Attachment F), which contains background information and rationale for the requirements in this Order, is hereby incorporated into and constitutes Findings for this Order. Attachments A through E are also incorporated into this Order. 2.3. Provisions and Requirements Implementing State Law. Some provisions/requirements in this Order are included to implement state law only . These provisions/requirements are not required or authorized under the federal CWA; consequently, violations of these provisions/requirements are not subject to the enforcement remedies that are available for NPDES violations. 2.4. Water Reclamation Requirements for Recycled Water Production and Use. This Order allows the production and use of disinfected secondary and tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements established by the California Department of Public Health in title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. Additionally, this Order includes water reclamation requirements for the Facility pursuant to the State Water Resources Control Board’s (State Water Board’s) Division of Drinking Water (DDW) recommendations submitted to the Central Coast Water Board. The distribution and offsite reuse of recycled water produced by the Facility is subject to the State Water Board’s General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW), or other applicable permit, dependent on final use. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 5 2.5. Response to Climate Change. Climate change refers to observed changes in regional weather patterns such as temperature, precipitation, and storm frequency and size. At the local scale, within urbanized areas, climate change may directly impact groundwater and surface water supply; drainage, flooding, and erosion patterns; and ecosystems and habitat. This shift in climate, combined with California’s growing population, has increased reliance on pumping, conveying, treating, and heating water, increasing the water sector’s greenhouse gas emissions. The State Water Board’s Resolution 2017 -0012, Comprehensive Response to Climate Change, requires a proactive response to climate change in all California Water Board actions, with the intent to embed climate change consideration into all programs and activities. Aligning with Resolution 2017 -0012, this Order supports the beneficial reuse of the Facility’s treated effluent to offset potable water supplies for irrigation and dedicated in -stream flows to support critical creek habitat. This Order incorporates requirements for the Facility to beneficially reuse treated effluent, which serves to diversify the State’s water supply portfolio to prepare for uncertainties in water resources due to the changing climate through ongoing implementation, monitoring, and updating of the Discharger’s climate action planning efforts using the best available data and technology for wastewater treatment and operation. In 2019, the City participated in the development of the Multi-Jurisdictional San Luis Obispo Hazard Mitigation, a planning effort that identifies and prioritizes the City’s vulnerability to hazards and outlines mitigation goals and objectives. In August 2020, the City adopted its Climate Action Plan with goals for community -wide carbon neutrality by 2035. Most recently, on January 17, 202 3, The City adopted the Climate Adaptation and Safety Element as part of its general plan. According to Disaster Mitigation Act (DMA) requirement §201.6(d)(3), the City must review and revise this plan within five years for continued mitigation project grant funding. Additionally, the City is currently undergoing construction of the SLO Water Plus project, which includes Facility upgrades to improve the Facility’s energy efficiency, provide flood protection improvements, increase treatment capacity, and improve resource recovery. To incorporate proactive planning for the future, this Order requires the Discharger to report on implementation progress, monitoring, and planning updates at this Facility as it relates to flooding, wildfire, renewable energy generation and energy efficiency, temperature, water recycling, biosolid s reuse, and influent flow and loading fluctuations exacerbated by climate change. 2.6. Human Right to Water. California Water Code section 106.3 established the policy that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. On January 26, 2017, the Central Coast Water Board adopted Resolution R3 -2017- 0004, which adopts the human right to water as a core value and affirms the realization of the human right to water and protecting human health as the Central Coast Water Board's top priorities. Consistent with the human right to water stated in California Water Code section 106.3, subdivision (a), and the Central Coast Water Board’s Resolution R3-2017-0004, this Order promotes actions that advance the human right to water and discourages actions that delay or impede opportunities for communities to secure safe, clean, affordable, and accessible CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 6 water adequate for human consumption, cooking, and sanitary purposes. This Order implements recently updated mercury water quality objectives that are more stringent than previous objectives to more adequately protect beneficial uses related to water and fish consumption. 2.7. Disadvantaged Community Status. Environmental Justice principles call for the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income in the development, adoption, implementation, and enforcement of all environmental laws, regulations, and policies that affect every community’s natural resources and the places people live, work, play, and learn. The Central Coast Water Board implements regulatory activities and water quality projects in a manner that ensures the fair treatment of all people, including Underrepresented Communities. Underrepresented Communities include but are not limited to Disadvantaged Communities (DACs), Severely Disadvantaged Communities (SDACs), Economically Distressed Areas (EDAs), Tribes, Environmentally Disadvantaged Communities (EnvDACs), and members of Fringe Communities.1 Furthermore, the Central Coast Water Board is committed to providing all stakeholders the opportunity to participate in the public process and provide meaningful input to decisions that affect communities. To meet environmental justice principles, staff has evaluated the disadvantaged community status for the Discharger. Using 2020 census data, the California Department of Water Resources Disadvantaged Community (DAC) Mapping Tool1 identifies 16 block groups in the City of San Luis Obispo, representing approximately 54 percent of the population, as disadvantaged communities. The tool defines a DAC as a census block with a median household income between $50,458 and $67,278 and a severely disadvantaged community (SDAC) as a census block with a median household income below $50,458. The SDAC census blocks in the City of San Luis Obispo have median household incomes of $8,075, $9,596, $11,935, $28,173, $28,284, $35,774, $39,526, and $44,167. The DAC census blocks in the City of San Luis Obispo have median household income of $51,074, $52,961, $55,769, $56,866, $57,175, $57,803, $58,083, and $60,417. 2.8. Notification of Interested Persons. The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provided them with an opportunity to submit their written comments and recommendations. Details of the notification are provided in the Fact Sheet, Attachment F. 2.9. Consideration of Public Comment. The Central Coast Water Board, in a public meeting, heard and considered all comments pertaining to the discharge. Details of the public hearing are provided in the Fact Sheet, Attachment F. THEREFORE, IT IS HEREBY ORDERED that this Order supersedes Order R3-2014- 0033, except for enforcement purposes, that Waste Discharge/Master Reclamation 1 The DAC Mapping Tool is used to inform statewide Integrated Water Resources Management (IRWM), Sustainable Groundwater Monitoring Act (SGMA), and California Water Plan implementation efforts and can be found at the following website: https://gis.water.ca.gov/app/dacs/. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 7 Requirements Order R3-2003-081 is terminated upon Discharger’s enrollment in State Water Board Order WQ-2016-0068-DDW, except for enforcement purposes, and, in order to meet the provisions contained in division 7 of the California Water Code (commencing with section 13000) and regulations adopted thereunder and the provisions of the CWA and regulations and guidelines adopted thereunder, the Discharger shall comply with the requirements in this Order. This action in no way prevents the Central Coast Water Board from taking enforcement action for violations of the previous orders. 3. DISCHARGE PROHIBITIONS 3.1. Discharge of treated wastewater at a location or in a manner other than as described by this Order at Discharge Points 001 and 002, with compliance measured at EFF-001 and EFF-002 respectively as described in the Monitoring and Reporting Program (MRP) Attachment E, is prohibited. 3.2. The discharge of any waste not specifically regulated by this Order, excluding stormwater regulated by General Permit CAS000001 (Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities), is prohibited. 3.3. The overflow or bypass of wastewater from the Discharger’s collection, treatment, or disposal facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7 (Bypass), is prohibited. 3.4. Creation of a condition of pollution, contamination, or nuisance, as defined by section 13050 of the California Water Code, is prohibited. 3.5. The discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat. 3.6. The discharge of radioactive substances is prohibited. 3.7. The average dry weather daily discharge flow shall not exceed 5.4 million gallons per day (MGD). 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS 4.1. Effluent Limitations – Discharge Point 001 4.1.1. Final Effluent Limitations – Discharge Point 001 4.1.1.1. The Discharger shall maintain compliance with the following effluent limitations at Discharge Point 001, with compliance measured at Monitoring Location EFF- 001A or EFF-001B as described in the Monitoring and Reporting Program (MRP), Attachment E. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 8 Table 2. Effluent Limitations at Discharge Point 001 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1,351 2,252 - - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - - TSS lbs/day[1] 425 1,351 3,378 - - - - pH[2],[3] standard units - - - 7.0 8.3 - - Oil and Grease mg/L 5 - 10 - - - - Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - - Dissolved Oxygen mg/L - - - 4.0 - - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.01 2 - 0.024 - - - - Chlorodibromom ethane (Dibromochlorom ethane) µg/L 0.40 - 0.81 - - - - Chloroform µg/L 60 - 120.6 - - - - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 9 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Dichlorobromom ethane µg/L 0.56 - 0.96 - - - - Methylene Chloride µg/L 4.7 - 9.45 - - - - Pentachlorophen ol µg/L 0.28 - 0.56 - - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - - Nitrite, Total mg/L 1 - - - - - - Un-ionized Ammonia mg/L 0.02 5 - - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - - Molybdenum mg/L 0.01 - - - - - - Total Dissolved Solids mg/L - - - - - 650[10] Chloride mg/L - - - - - 100[10] Sodium mg/L - - - - - 50[10] Sulfate mg/L -- - - - - 100[10] Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail ” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 10 [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 7.0-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 7.0-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0 -9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 7.0-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 - day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in -stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP -Attachment E). [10] Based on a 12-month running mean. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 11 4.1.1.2. Percent Removal: The average monthly percent removal of BOD 5-day at 20°C and total suspended solids shall not be less than 85 percent. 4.1.1.3. Floating Material: Discharge of treated wastewater through Discharge Point 001 shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 4.1.2. Interim Effluent Limitations – Not Applicable 4.2. Land Discharge Specifications – Not Applicable 4.3. Recycling Specifications – Discharge Point 002 As specified below, this Order conditionally authorizes the Discharger to act as the producer of recycled (or reclaimed) water and to reuse recycled water onsite at the Facility and for other purposes. The Discharger is responsible for compliance with all applicable requirements associated with the production and onsite use of recycled water as specified within this Order. The Discharger filed a California Code of Regulations title 22 engineering report on August 14, 2020, that described recycled water quality produced at the Facility as "disinfected tertiary" (as defined in title 22, section 60301.230) and submitted a Notice of Intent (NOI) on August 14, 2020, to enroll under the State Water Board General Water Reclamation Requirements for Recycled Water Use (Order WQ 2016-0068-DDW). The distribution and offsite reuse of recycled water produced by the Facility are subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. Order WQ 2016-0068-DDW supersedes Waste Discharge/Master Reclamation Requirements Order R3-2003-081. 4.3.1. Reclamation and use of treated wastewater shall adhere to applicable requirements of California Water Code sections 13500-13577 (Water Reclamation) and California Code of Regulations, title 17 sections 7583-7586, title 17 sections 7601-7605, and title 22 sections 60301-60355 (Uniform Statewide Recycling Criteria). 4.3.2. Recycled water production shall comply with a title 22 engineering report approved by DDW that demonstrates or defines compliance with the Uniform Statewide Recycling Criteria. 4.3.3. Recycled water shall be disinfected tertiary recycled water, as defined by California Code of Regulations title 22, section 60301.230. 4.3.4. Recycled water shall be adequately filtered, and disinfected, as defined in title 22. 4.3.5. Turbidity in tertiary recycled water shall not exceed any of the following limits: 4.3.5.1. An average of 0.2 NTU within a 24-hour period; and 4.3.5.2. 0.5 NTU at any time. 4.3.6. Total coliform bacteria measured in the disinfected recycled water shall not exceed the following limits: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 12 4.3.6.1. An MPN of 2.2 per 100 mL calculated as a median concentration utilizing the bacteriological results of the last seven days for which analyses have been completed, 4.3.6.2. An MPN of 23 per 100 mL in more than one sample in any 30-day period, and 4.3.6.3. No sample shall exceed an MPN of 240 total coliform bacteria per 100 mL. 4.3.7. The Discharger shall discontinue delivery of recycled water to distributors and users during any period in which it has reason to believe that the limits established in this Order are not being met. The delivery of recycled water shall not be resumed until all conditions that caused the limits to be violated have been corrected. 4.3.8. Recycled water shall not exceed any maximum contaminant level established pursuant to sections 116275(c)(1) and (d) of the California Health and Safety Code or established by the U.S. EPA. 4.3.9. Recycled water disinfected with chlorine shall have a chlorine concentration time modal contact time (CT) value of not less than 450 mg-min/L at all times with a modal contact time of at least 90 minutes based on peak dry weather design flow. 4.3.10 If a disinfection method other than chlorine is used, the disinfection process shall be a process that, when combined with the filtration process, has been demonstrated to inactivate and/or remove 99.999 percent of the plaque forming units of F-specific bacteriophage MS2, or polio virus in the wastewater. A virus that is at least as resistant to disinfection as polio virus may be used for purposes of the demonstration. 4.3.11. The Discharger shall adhere to the manufacturer’s recommended operating conditions for the ultraviolet (UV) system. 4.3.12. Personnel involved in producing, transporting, or using recycled water shall be informed of possible health hazards that may result from contact and use of recycled water. 4.3.13. All areas where recycled water is in use and with public access shall be posted with signs in English and an international symbol to warn the public that recycled wastewater is being stored or used. 4.3.14. Recycled water systems at the Facility shall be properly labeled and regularly inspected to ensure proper operation, absence of leaks, and absence of illegal connections. 5. RECEIVING WATER LIMITATIONS 5.1. Surface Water Limitations Receiving water limitations are based on water quality objectives contained in the Water Quality Control Plan for the Central Coastal Basin (Basin Plan) and are a required part of this Order. The discharge shall not cause a violation of the following receiving water limitations in San Luis Obispo Creek. The discharge from the wastewater treatment facility shall comply with the following in the receiving waters: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 13 5.1.1. Waters shall be free of coloration that causes nuisance or adversely affects beneficial uses. Coloration attributable to materials of waste origin shall not be greater than 15 units or 10 percent above natural background color, whichever is greater. 5.1.2. Waters shall not contain taste or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, that cause nuisance, or that adversely affect beneficial uses. 5.1.3. Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.4. Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.5. Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. 5.1.6. Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. 5.1.7. Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses. 5.1.8. The suspended sediment load and suspended sediment discharge rate to surface waters shall not be altered in such a manner as to cause nuisance or adversely affect beneficial uses. 5.1.9 Concentrations of toxic metals and inorganic chemicals in waters shall not be increased in such a manner that may adversely affect beneficial uses. 5.1.10. Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Increase in turbidity attributable to controllable water quality factors shall not exceed the following limits. 5.1.10.1. Where natural turbidity is between 0 and 50 NTUs, increases shall not exceed 20 percent. 5.1.10.2. Where natural turbidity is between 50 and 100 NTUs, increases shall not exceed 10 NTU. 5.1.10.3. Where natural turbidity is greater than 100 NTUs, increases shall not exceed 10 percent. 5.1.11. The pH value shall not be depressed below 7.0 nor raised above 8.3. The change in normal ambient pH levels shall not exceed 0.5 units. 5.1.12. Dissolved oxygen concentrations in receiving waters shall not be reduced below 7.0 mg/L at any time. 5.1.13. Discharged effluent shall not cause the receiving water temperature to increase more than 5° Fahrenheit (F) above the receiving water temperature. If, due to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 14 the Creek’s low temperature as determined by early-morning monitoring, the discharge causes the Creek’s temperature to exceed the limit, the Discharger must ensure the discharge shall not cause the receiving water to exceed 72.5° F (22.5° C). The discharger shall monitor the Creek again four hours after discovering the exceedance and shall report both results to the Executive Officer in the monthly self-monitoring report. 5.1.14. All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge. 5.1.15. The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/L (as N) in the receiving water. 5.1.16. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect the beneficial uses of the receiving water. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life. For waters where existing concentrations are presently nondetectable or where beneficial uses would be impaired by concentrations in excess of nondetectable levels, total identifiable chlorinated hydrocarbon pesticides shall not be present at concentrations detectable within the accuracy of analytical methods as prescribed in Standard Methods for the Examination of Water and Wastewater, latest edition, or other equivalent methods approved by the Executive Officer. 5.1.17. Waters shall not contain organic substances in concentrations greater than those listed in the table below: Table 3. Organic Substances Water Quality Criteria Parameter Units Water Quality Objective Methylene Blue Activated Substances mg/L 0.2 Phenols ug/L 1.0 Polychlorinated Biphenyls (PCBs) [1] µg/L 0.3 Phthalate Esters µg/L 0.002 [1] PCBs refer to sum of PCB 1016, 1221, 1232, 1242, 1248, 1254, and 1260. 5.1.18. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstance shall receiving waters contain concentrations of radionuclides in excess of the maximum contaminant levels (MCLs) for radioactivity presented in title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.1.19. Receiving waters shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 15 Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.1.20. Receiving waters shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural beneficial use . Interpretation of adverse effects shall be derived from the University of California Agricultural Extension Service guidelines presented in section 3, Table 3-1 of the 2019 Basin Plan. 5.1.21. Receiving waters shall not contain concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in section 3, Table 3-2 of the Basin Plan. Salt concentrations for irrigations waters shall be controlled through implementation of the anti-degradation policy to the effect that mineral constituents of currently or potentially usable waters shall not be increased. 5.1.22. Receiving waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife in excess of the levels presented in section 3, Table 3-3 of the 2019 Basin Plan. The concentrations of metals listed in the table below shall not be exceeded for the protection of aquatic life. Table 4. Hardness Dependent Metals Criteria Parameter Units Receiving Water Hardness >100 mg/L calcium carbonate (CaCO3) Receiving Water Hardness <100 mg/L CaCO3 Cadmium mg/L 0.003 0.0004 Chromium mg/L 0.05 0.05 Copper mg/L 0.03 0.01 Lead mg/L 0.03 0.03 Mercury mg/L 0.0002 0.0002 Nickel mg/L 0.4 0.1 Zinc mg/L 0.2 0.004 5.1.23. E. coli concentrations shall not exceed 100 MPN/100 mL as a 6-week rolling geometric mean, calculated weekly. A statistical threshold value (STV) of 320 MPN/100 mL for E. coli shall not be exceeded by more than 10 percent of samples collected in a calendar month, calculated in a static manner. 5.1.24. Discharges shall not cause receiving water to exceed the water quality objectives for the Estero Bay Hydrologic Unit (San Luis Obispo Creek Sub-Area) specifically identified by Table 3-5 of the 2019 Basin Plan, as shown in the table below. Objectives shown are annual mean values. Objectives are based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 5. Annual Mean Surface Water Quality Objectives CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 16 Parameter Units Annual Mean Total Dissolved Solids mg/L 650 Chloride mg/L 100 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 5.2. Groundwater Limitations Activities at the Facility shall not cause exceedance/deviation from the following water quality objectives for groundwater established by the 2019 Basin Plan. The Central Coast Water Board may require the Discharger to investigate the cause of exceedances in the groundwater before determining whether the Discharger caused any water condition that exceeds the following groundwater limitations. 5.2.1. Groundwater shall not contain taste or odor-producing substances in concentrations that adversely affect beneficial uses. 5.2.2. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstances shall groundwater contain concentrations of radionuclides in excess of the MCLs for radioactivity presented in Title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.2.3. The Discharger shall not cause a statistically significant increase of mineral constituent concentrations in underlying groundwater as determined by comparison of samples collected from wells located up-gradient and down- gradient of the waters affected by the discharge. 5.2.4. The median concentration of coliform organisms in groundwater, over any seven - day period, shall be less than 2.2 organisms per 100 mL. 5.2.5. Groundwater shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431 -A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.2.6. Groundwater shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural supply beneficial use. Interpretation of adverse effects shall be as derived in University of California Agricultural Extension Service guidelines provided in Table 3-1 of the 2019 Basin Plan. 5.2.7. Groundwater used for irrigation and livestock watering shall not exceed concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in chapter 3, Table 3 -2 of the 2019 Basin Plan. 5.2.8. Groundwater shall not contain constituents greater than the following concentrations established in Table 3-6 of the 2019 Basin Plan for groundwaters within the San Luis Obispo Creek sub-area (Estero Bay sub-basin). Objectives CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 17 shown are annual median values. Objectives based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 6. Groundwater Objectives Parameter Units Annual Median TDS mg/L 900 Chloride mg/L 200 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 Nitrogen mg/L 5 6. PROVISIONS 6.1. Standard Provisions 6.1.1. The Discharger shall comply with all Standard Provisions included in Attachment D. 6.1.2. The Discharger shall comply with Central Coast Water Board Standard Provisions in Attachment D. In the event that there is any conflict, duplication, or overlap between provisions specified by this Order, the more stringent provision shall apply. 6.2. Monitoring and Reporting Program (MRP) Requirements The Discharger shall comply with the MRP, and future revisions thereto, in Attachment E. 6.3. Special Provisions 6.3.1. Reopener Provisions 6.3.1.1. This Order may be reopened for modification, or revocation and reissuance, as a result of the detection of a reportable priority pollutant generated by special conditions included in this Order. These special conditions may be, but are not limited to, fish tissue sampling, whole effluent toxicity, monitoring requirements on internal waste stream(s), monitoring for surrogate parameters, and other new information. Additional requirements may be included in this Order as a result of the special condition monitoring data. 6.3.1.2. This Order may be reopened and modified in accordance with NPDES regulations at 40 Code of Federal Regulations (CFR) parts 122 and 124, as necessary, to include additional conditions or limitations based on newly available information or to implement any U.S. EPA approved, new, state water quality objective. 6.3.1.3. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 18 to cause, or contributes to an excursion above a State Implementation Policy (SIP) water quality objective. 6.3.1.4. This Order may be reopened and modified to revise the most sensitive species to be used for acute and/or chronic aquatic toxicity testing once the required species sensitivity is completed in accordance with section 5 of the MRP (Attachment E). Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. 6.3.1.5 This Order may be reopened and modified to reevaluate reasonable potential for acute toxicity, and establish acute toxicity effluent limitations, if warranted, after the evaluation of new data and information. 6.3.2. Special Studies, Technical Papers and Additional Monitoring Requirements 6.3.2.1. Toxicity Reduction Requirements For compliance with the Basin Plan’s narrative toxicity objective, this Order requires the Discharger to conduct acute and chronic whole effluent toxicity (WET) testing, as specified in section 5 of the MRP. Furthermore, this Provision requires the Discharger to investigate the causes of and identify corrective actions to reduce or eliminate effluent toxicity. If the discharge exceeds the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring established in this Provision, the Discharger is required to initiate a Toxicity Reduction Evaluation (TRE) in accordance with an approved TRE Work Plan and take actions to mitigate the impact of the discharge and prevent recurrence of toxicity. A TRE is a site-specific study conducted in a stepwise process to identify the source(s) of toxicity and the effective control measures for effluent toxicity. TREs are designed to identify the causative agents and sources of whole effluent toxicity, evaluate the effectiveness of the toxicity control options, and confirm the reduction in effluent toxicity. This Provision includes requirements for the Discharger to update and submit their TRE Work Plan and includes procedures for accelerated toxicity monitoring and TRE initiation: 6.3.2.1.1. TRE Work Plan. Within 90 days of the effective date of this Order, the Discharger shall submit to the Central Coast Water Board an updated TRE Work Plan for approval by the Executive Officer. The TRE Work Plan shall outline the procedures for identifying the source(s) of and reducing or eliminating effluent toxicity. The TRE Work Plan must be developed in accordance with U.S. EPA guidance and be of adequate detail to allow the Discharger to immediately initiate a TRE as required in this Provision. 6.3.2.1.2. Accelerated Monitoring and TRE Initiation. When the numeric toxicity monitoring trigger or effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all test acceptability criteria (TAC), the Discharger shall initiate accelerated monitoring as required in the Accele rated Monitoring Specifications in section 5 of the MRP. The Discharger shall initiate a TRE to address effluent toxicity if any WET testing results exceed CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 19 the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring. 6.3.3. Best Management Practices and Pollution Prevention 6.3.3.1. Salt and Nutrient Management Program 6.3.3.1.1 The Discharger shall continue to update and implement an ongoing Salt Management Program, with the intent of reducing mass loading of salts in treated effluent and attainment of applicable water quality objectives for salts in the San Luis Obispo Creek Sub-Basin Area of the Estero Bay Drainage Basin. Additionally, the Discharger shall continue to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable water quality objectives for nutrients in the same basin. 6.3.3.1.2 Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. 6.3.3.1.3 Nutrient reduction measures shall focus on optimizing wastewater treatment processes for nitrification and denitrification, or other means of nitrogen removal. Reduction measures may also include source control (non-human waste from commercial and industrial sources) as appropriate. 6.3.3.1.4 As part of the Salt and Nutrient Management Program, the Discharger shall submit an annual report describing salt and nutrient reduction efforts as described in the section 9.3 of the MRP (Attachment E). 6.3.3.1.5 As an alternative to the Salt and Nutrient Management Program requirements described above, upon Executive Officer approval, the Discharger may submit documentation and summary of participation in a regional salt/nutrient management plan implemented under the provisions of State Water Board Resolution No. 2018-0057 (Recycled Water Policy). 6.3.3.2. Pollutant Minimization Program 6.3.3.2.1.The Discharger shall develop and conduct a Pollutant Minimization Program (PMP) as further described below when there is evidence (e.g., sample results reported as detected not quantifiable (DNQ) when the effluent limitation is less than the MDL, sample results from analytical methods more sensitive than those methods required by this Order, presence of whole effluent toxicity, health advisories for fish consumption, results of benthic or aquatic organism tissue sampling) that a priority pollutant is present in the effluent above an effluent limitation and either: 6.3.3.2.1.1. A sample result is reported as DNQ and the effluent limitation is less than the reporting limit (RL); or 6.3.3.2.1.2. A sample result is reported as non-detect (ND) and the effluent limitation is less than the MDL, using definitions described in Attachment A and reporting protocols described in MRP section 10.2.4. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 20 6.3.3.2.2. The PMP shall include, but not be limited to, the following actions and submittals acceptable to the Central Coast Water Board Executive Officer: 6.3.3.2.2.1. An annual review and semi-annual monitoring of potential sources of the reportable priority pollutant(s), which may include fish tissue monitoring and other bio-uptake sampling; 6.3.3.2.2.2. Quarterly monitoring for the reportable priority pollutant(s) in the influent to the wastewater treatment system; 6.3.3.2.2.3. Submittal of a control strategy designed to proceed toward the goal of maintaining concentrations of the reportable priority pollutant(s) in the effluent at or below the effluent limitation; 6.3.3.2.2.4. Implementation of appropriate cost-effective control measures for the reportable priority pollutant(s), consistent with the control strategy; and 6.3.3.1.2.5. An annual status report that shall be sent to the Central Coast Water Board including: 6.3.3.1.2.5.1. All PMP monitoring results for the previous year; 6.3.3.1.2.5.2. A list of potential sources of the reportable priority pollutant(s); 6.3.3.1.2.5.3. A summary of all actions undertaken pursuant to the control strategy; and 6.3.3.1.2.5.4. A description of actions to be taken in the following year. 6.3.4. Construction, Operation and Maintenance Specifications 6.3.4.1. The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.3.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.3.5.1. Biosolids. The handling, management, and disposal of sludge and solids derived from wastewater treatment must comply with applicable provisions of U.S. EPA regulations at 40 CFR sections 257, 258, 501, and 503, including all monitoring, record keeping, and reporting requirements. Solids and sludge treatment, storage, and disposal or reuse shall not create a nuisance, such as objectionable odors or flies, and shall not result in ground water contamination. Sites for solids and sludge treatment and storage shall have adequate facilities to divert surface water runoff from adjacent areas to protect the boundaries of such sites from erosion, and to prevent drainage from treatment and storage sites. The treatment, storage, disposal, or reuse of sewage sludge and solids shall not cause waste material to be in a position where it is, or can be, conveyed from the treatment and storage sites and deposited into waters of the State. The Discharger is responsible for assuring that all biosolids produced at its facility are used or disposed of in accordance with the above rules, regardless of whether the Discharger uses or disposes of the biosolids itself, or transfers them to another party for further treatment, use, or disposal. The Discharger is CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 21 responsible for informing subsequent preparers, appliers, and disposers of the requirements that they must adhere to these rules. 6.3.5.2. Pretreatment. The Discharger shall be responsible for the performance for all pretreatment requirements contained in 40 CFR part 403 and shall be subject to enforcement actions, penalties, fines, and other remedies by the U.S. EPA, or other appropriate parties, as provided in the CWA, as amended (33 USC 1351 et seq.). The Discharger shall implement and enforce its approved POTW Pretreatment Program. The Discharger’s approved POTW Pretreatment Program is hereby made an enforceable condition of this permit. U.S. EPA or the Central Coast Water Board may initiate enforcement action against an industrial user for noncompliance with applicable standards and requirements as provided in the CWA. The Discharger shall enforce the requirements promulgated under sections 307 (b), 307 (c), 307 (d), and 402 (b) of the CWA. The Discharger shall cause industrial users subject to Federal Categorical Standards to achieve compliance no later than the date specified in those requirements or, in the case of a new industrial user, upon commencement of the discharge. The Discharger shall perform the pretreatment functions as required in 40 CFR part 403, including, but not limited to the following: 6.3.5.2.1. Implement the necessary authorities as provided in 40 CFR section 403.8 (f) (1); 6.3.5.2.2. Enforce the pretreatment requirements under 40 CFR sections 403.5 and 403.6; 6.3.5.2.3. Implement the programmatic functions as provided in 40 CFR section 403.8 (f) (2); and 6.3.5.2.4. Provide the requisite funding and personnel to implement the pretreatment program as provided in 40 CFR section 403.8 (f) (3). 6.3.5.5. Resource Recovery from Anaerobically Digestible Material. If the Discharger will receive hauled-in anaerobically digestible material for injection into an anaerobic digester, the Discharger shall notify the Central Coast Water Board and develop and implement standard operating procedures for this activity. The standard operating procedures shall be developed prior to receiving hauled-in anaerobically digestible material. The standard operating procedures shall address material handling, including unloading, screening, or other processing prior to anaerobic digestion; transportation; spill prevention; and spill response. In addition, the standard operating procedures shall address avoidance of the introduction of materials that could cause interference, pass- through, or upset of the treatment processes; avoidance of prohibited material; vector control; odor control; operation and maintenance; and the disposit ion of any solid waste segregated from introduction to the digester. The Discharger shall train its staff on the standard operating procedures and shall maintain records for a minimum of five years for each load received, describing the hauler, waste type, and quantity received. In addition, the Discharger shall CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 22 maintain records for a minimum of five years for the disposition, location, and quantity of cumulative pre-digestion-segregated solid waste hauled offsite. 6.3.6. Other Special Provisions 6.3.6.1. Salt Management. Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. The Discharger shall assess additional pretreatment measures that may be taken to reduce influent salt concentrations and include a discussion of proposed and implemented measures in the annual report described below. The Discharger must also implement outreach to residential, commercial, and industrial salt contributors with the goal of reducing salts discharged to the collection system. 6.3.6.2. Discharges of Stormwater. For the control of stormwater discharged from the site of the wastewater treatment and disposal facilities, if applicable, the Discharger shall seek authorization to discharge under and meet the requirements of the State Water Board’s Water Quality Order 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.3.6.3. Statewide General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order No. 2022-0103-DWQ) The Discharger is subject to the requirements of and must separately comply with State Water Board Order 2022-0103-DWQ, Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems, including monitoring and reporting requirements, and any subsequent revision to that order. This General Permit, adopted on December 6, 2022, is applicable to all “federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California.” The purpose of the General Permit is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled under the General Permit. 6.3.6.4. Climate Change Adaptation Implementation Progress Report. On May 1, 2029, the Discharger shall submit a Climate Change Adaptation Implementation Progress Report2 to the Central Coast Water Board Executive Officer describing the Discharger’s progress in implementing, monitoring, and updating its long-term approach for identifying and addressing climate change hazards and vulnerabilities at the Facility, including all associated infrastructure (e.g., treatment facilities, conveyances to discharge points, discharge facilities). 2 In place of a static document, the Discharger may develop a living document and/or set of tools that fulfills the components outlined for the Climate Change Adaptation Program. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 23 The Climate Change Adaptation Implementation Report shall, at a minimum, include the following components: 6.3.6.4.1. Climate Change Adaptation Implementation Status – Provide a status update on any city or county-wide reports that address Facility and or collection system climate change adaptation planning and or implantation. Submit copies of document(s) to CIWQS as attachments. 6.3.6.4.2. Resiliency Actions – Report progress on actions that build facility and operational resilience to identified vulnerabilities, accounting for options that minimize resource impacts. For the anticipated life of the facility, include an analysis of: • Precipitation pattern changes o Drought – Decreased influent quantity and quality o Peak Events – Flooding and increased influent quantity • Temperature fluctuations and extremes • Increased wildfires • Energy resilience o Energy efficiency o Renewable energy generation o Increased power outages • Biosolid reuse • Water recycling 6.3.6.4.3. Adaptation Strategy – Report progress and adjustments made to strategy to complete Resiliency Actions, encompassing the following: 6.3.6.4.3.1. Prioritization – How resiliency actions were prioritized based on risks to water quality, but also accounting for costs and benefits. 6.3.6.4.3.2. Schedule and Milestones – Ongoing and changing timeframes to complete prioritized resiliency actions and/or climate change hazard triggers to inform when the Discharger shall implement actions. Milestones to complete critical steps for prioritized Resiliency Actions, designed to demonstrate measurable progress at a steady, or accelerated, completion pace over the established timeframes. 6.3.6.4.3.3. Financial Planning – Costs of reported implementation and monitoring measures, projected costs necessary to continue implementation and monitoring of resiliency actions, and strategy to procure funds. 6.3.7. Compliance Schedules – Not Applicable 7. COMPLIANCE DETERMINATION 7.1. General Compliance with effluent limitations for reportable pollutants shall be determined using sample reporting protocols defined in the MRP and Attachment A of this Order. For purposes of reporting and administrative enforcement by the Central Coast and State Water Boards, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the reportable pollutant in the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 24 monitoring sample is greater than the effluent limitation and greater than or equal to the reported Minimum Level (ML). 7.2. Chronic Toxicity The discharge is subject to determination of “Pass” or “Fail” from a chronic toxicity test using the Test of Significant Toxicity (TST) statistical t-test approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. The null hypothesis (Ho) for the TST statistical approach is: Mean discharge “in-stream” waste concentration (IWC) response ≤0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub -lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge (100 percent effluent) and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be reported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). 7.3. Multiple Sample Data When determining compliance with a measure of central tendency (arithmetic mean, geometric mean, median, etc.) of multiple samples analyses and the data set contains one or more reported determinations of DNQ, or ND, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 7.3.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 7.3.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 25 even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 7.4. Average Monthly Effluent Limitation (AMEL) If the average of daily discharges over a calendar month exceeds the AMEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that month for that parameter (e.g., resulting in 31 days of non-compliance in a 31-day month). The average of daily discharges over the calendar month that exceeds the AMEL for a parameter will be considered out of compliance for that month only. If only a single sample is taken during the calendar month and the analytical result for that sample exceeds the AMEL, the Discharger will be considered out of compliance for that calendar month. For any one calendar month during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar month. 7.5. Average Weekly Effluent Limitation (AWEL) If the average of daily discharges over a calendar week exceeds the AWEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that week for that parameter, resulting in seven days of non-compliance. The average of daily discharges over the calendar week that exceeds the AWEL for a parameter will be considered out of compliance for that week only. If only a single sample is taken during the calendar week and the analytical result for that sample exceeds the AWEL, the Discharger will be considered out of compliance for that calendar week. For any one calendar week during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar week. 7.6. Maximum Daily Effluent Limitation (MDEL) If a daily discharge exceeds the MDEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for that parameter for that one day only within the reporting period. For any one day during which no sample is taken, no compliance determination can be made for that day. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-1 A. ATTACHMENT A – DEFINITIONS Arithmetic Mean (μ) Also called the average, is the sum of measured values divided by the number of samples. For ambient water concentrations, the arithmetic mean is calculated as follows: where: Σx is the sum of the measured ambient water concentrations, and n is the number of samples. Average Monthly Effluent Limitation (AMEL) The highest allowable average of daily discharges over a calendar month, calculated as the sum of all daily discharges measured during a calendar month divided by the number of daily discharges measured during that month. Average Weekly Effluent Limitation (AWEL) The highest allowable average of daily discharges over a calendar week (Sunday through Saturday), calculated as the sum of all daily discharges measured during a calendar week divided by the number of daily discharges measured during that week. Bioaccumulative Those substances taken up by an organism from its surrounding medium through gill membranes, epithelial tissue, or from food and subsequently concentrated and retained in the body of the organism. Bioassay A test used to evaluate the relative potency of a chemical or a mixture of chemicals by comparing its effect on a living organism with the effect of a standard preparation on the same type of organism. Calendar Month(s) A period of time from a day of one month to the day before the corresponding day of the next month if the corresponding day exists, or if not to the last day of the next month (e.g., from January 1 to January 31, from June 15 to July 14, or from January 31 to February 28). Calendar Quarter A period of time defined as three consecutive calendar months. Calendar Year A period of time defined as twelve consecutive calendar months. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-2 Carcinogenic Pollutants are substances that are known to cause cancer in living organisms. Chronic Aquatic Toxicity Test A test to determine an adverse effect (sublethal or lethal) on a group of aquatic test organisms during an exposure of duration long enough to assess sub -lethal effects. Compliance with the effluent limitation for chronic toxicity in this Order is demonstr ated by conducting chronic toxicity tests for the effluent as described in section 7.15 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E), and in accordance with the TST statistical approach. Coefficient of Variation (CV) CV is a measure of the data variability and is calculated as the estimated standard deviation divided by the arithmetic mean of the observed values. Continuous Dischargers Facilities that discharge without interruption throughout its operating hours, except for infrequent shutdowns for maintenance, process changes, or other similar activities, and that discharge throughout the calendar year. Daily Discharge Daily Discharge is defined as either: (1) the total mass of the constituent discharged over the calendar day (12:00 am through 11:59 pm) or any 24 -hour period that reasonably represents a calendar day for purposes of sampling (as specified in the permit), for a constituent with limitations expressed in units of mass or; (2) the unweighted arithmetic mean measurement of the constituent over the day for a constituent with limitations expressed in other units of measurement (e.g., concentration). The daily discharge may be determined by the analytical results of a composite sample taken over the course of one day (a calendar day or other 24-hour period defined as a day) or by the arithmetic mean of analytical results from one or more grab samples taken over the course of the day. For composite sampling, if one day is defined as a 24-hour period other than a calendar day, the analytical result for the 24-hour period will be considered as the result for the calendar day in which the 24-hour period ends. Detected, but Not Quantified (DNQ) DNQ are those sample results less than the reporting limit (RL), but greater than or equal to the laboratory’s MDL. Sample results reported as DNQ are estimated concentrations. Dilution Credit Dilution Credit is the amount of dilution granted to a discharge in the calculation of a water quality-based effluent limitation, based on the allowance of a specified mixing zone. It is calculated from the dilution ratio or determined through conducting a mixing zone study or modeling of the discharge and receiving water. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-3 Dilution Ratio The critical low flow of the upstream receiving water divided by the flow of the effluent discharged. Effluent Concentration Allowance (ECA) ECA is a value derived from the water quality criterion/objective, dilution credit, and ambient background concentration that is used, in conjunction with the coefficient of variation for the effluent monitoring data, to calculate a long -term average (LTA) discharge concentration. The ECA has the same meaning as wasteload allocation (WLA) as used in United States Environmental Protection Agency (U.S. EPA) guidance (Technical Support Document for Water Quality-based Toxics Control, March 1991, second printing, EPA/505/2-90-001). Enclosed Bays Enclosed Bays means indentations along the coast that enclose an area of oceanic water within distinct headlands or harbor works. Enclosed bays include all bays where the narrowest distance between the headlands or outermost harbor works is less than 75 percent of the greatest dimension of the enclosed portion of the bay. Enclosed bays include, but are not limited to, Humboldt Bay, Bodega Harbor, Tomales Bay, Drake’s Estero, San Francisco Bay, Morro Bay, Los Angeles-Long Beach Harbor, Upper and Lower Newport Bay, Mission Bay, and San Diego Bay. Enclosed bays do not include inland surface waters or ocean waters. Estimated Chemical Concentration The estimated chemical concentration that results from the confirmed detection of the substance by the analytical method below the minimum level (ML) value. Estuaries and Coastal Lagoons Estuaries means waters, including coastal lagoons, located at the mouths of streams that serve as areas of mixing for fresh and ocean waters. Coastal lagoons and mouths of streams that are temporarily separated from the ocean by sandbars shall be considered estuaries. Estuarine waters shall be considered to extend from a bay or the open ocean to a point upstream where there is no significant mixing of fresh water and seawater. Estuarine waters included, but are not limited to, the Sacramento-San Joaquin Delta, as defined in California Water Code section 12220, Suisun Bay, Carquinez Strait downstream to the Carquinez Bridge, and appropriate areas of the Smith, Mad, Eel, Noyo, Russian, Klamath, San Diego, and Otay rivers. Estuaries do not include inland surface waters or ocean waters. Flow-Through Acute Toxicity Testing Systems A toxicity testing system where an effluent sample is either pumped continuously from the sampling point directly to a dilutor system, or collected and placed in a tank adjacent to the test laboratory and pumped continuously from the tank to a dilutor syst em. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-4 Inland Surface Waters All surface waters of the state that do not include the ocean, enclosed bays, or estuaries. Insignificant Dischargers National Pollutant Discharge Elimination System (NPDES) discharges that are determined to be a very low threat to water quality by the permitting authority. Instantaneous Maximum Effluent Limitation The highest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous maximum limitation). Instantaneous Minimum Effluent Limitation The lowest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous minimum limitation). In-stream Waste Concentration (IWC) The concentration of effluent in the receiving water after mixing as determined by the permitting authority. For purposes of aquatic toxicity testing for non-stormwater NPDES dischargers, the IWC shall be as described in section III.C.1 of the Toxicity Provisions. For assessing whether receiving waters meet the numeric water quality objectives (WQOs), the undiluted ambient water shall be used as the IWC in the TST as indicated in section III.B.3 of the Toxicity Provisions. Maximum Daily Effluent Limitation (MDEL) The highest allowable daily discharge of a pollutant, over a calendar day (or 24 -hour period). For pollutants with limitations expressed in units of mass, the daily discharge is calculated as the total mass of the pollutant discharged over the day. For pollutants with limitations expressed in other units of measurement, the daily discharge is calculated as the arithmetic mean measurement of the pollutant over the day. For the purposes of chronic and acute aquatic toxicity, an MDEL is an effluent limitation based on the outcome of the TST approach and the resulting percent effect at the IWC, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Maximum Daily Effluent Target (MDET) For the purposes of chronic and acute aquatic toxicity, an MDET is a target used to determine whether a Toxicity Reduction Evaluation (TRE) should be conducted. Not meeting the MDET is not a violation of an effluent limitation. Median The middle measurement in a set of data. The median of a set of data is found by first arranging the measurements in order of magnitude (either increasing or decreasing order) If the number of measurements (n) is odd, then: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-5 If n is even, then: (i.e., the midpoint between the (n/2 and ((n/2)+1))). Median Monthly Effluent Limitation (MMEL) For the purposes of chronic and acute aquatic toxicity, an MMEL is an effluent limitation based on a maximum of three independent toxicity tests, analyzed using the TST, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Median Monthly Effluent Target (MMET) For the purposes of chronic and acute aquatic toxicity, an MMET is a target based on a maximum of three independent toxicity tests used to determine whether a TRE should be conducted. Not meeting the MMET is not a violation of an effluent limitation. Method Detection Limit (MDL) MDL is the minimum concentration of a substance that can be reported with 99 percent confidence that the measured concentration is distinguishable from method blank results, as defined in 40 Code of Federal Regulations (CFR) part 136, Attachment B. Minimum Level (ML) ML is the concentration at which the entire analytical system must give a recognizable signal and acceptable calibration point. The ML is the concentration in a sample that is equivalent to the concentration of the lowest calibration standard analyzed by a specific analytical procedure, assuming that all the method specified sample weights, volumes, and processing steps have been followed. Mixing Zone Mixing Zone is a limited volume of receiving water that is allocated for mixing with a wastewater discharge where water quality criteria can be exceeded without causing adverse effects to the overall water body. MMEL Compliance Tests For the purposes of chronic and acute aquatic toxicity, MMEL compliance tests are a maximum of two tests that are used in addition to the routine monitoring test to determine compliance with the chronic and acute aquatic toxicity MMEL and MDEL. MMET Tests For the purposes of chronic and acute aquatic toxicity, for dischargers not required to comply with numeric chronic toxicity effluent limitations, MMET tests are a maximum of two tests that are used in addition to the routine monitoring test to determine w hether a TRE should be conducted. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-6 Most Sensitive Species The single species selected from an array of test species to be used in a single species laboratory test series to determine toxic effects of effluent or ambient water. Non-Continuous Dischargers Dischargers that do not discharge in a continuous manner or do not discharge throughout the calendar year (e.g., intermittent and seasonal dischargers). Non-NPDES Dischargers Dischargers of waste that could affect the quality of waters of the State that are not regulated by the NPDES program. Non-Stormwater NPDES Dischargers Dischargers that are regulated pursuant to one or more NPDES permit(s), but excluding any discharges subject to the United States Code title 33 section 1342(p). This includes dischargers that discharge a combination of treated municipal or industrial wastewater and stormwater. Nonpoint Source A source that does not meet the definition of a point source, as defined below. Not Detected (ND) Sample results which are less than the laboratory’s MDL. Null Hypothesis A statement used in statistical testing that has been put forward either because it is believed to be true or because it is to be used as a basis for argument, but has not been proved. Ocean Waters The territorial marine waters of the State, as defined by California law, to the extent these waters are outside of enclosed bays, estuaries, and coastal lagoons. Discharges to ocean waters are regulated in accordance with the State Water Board’s Californi a Ocean Plan. Percent Effect The value that denotes the difference in response between the test concentration and the control, divided by the mean control response, and multiplied by 100. Permitting Authority The State Water Board or a regional water board that issues a permit, waste discharge requirements, water quality certification, or other authorization for the discharge or proposed discharge of waste. To the extent that the action is delegable, the term “Permitting Authority” can include the Executive Officer or Executive Director. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-7 Persistent Pollutants Persistent pollutants are substances for which degradation or decomposition in the environment is nonexistent or very slow. Point Source Any discernible, confined and discrete conveyance including, but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from whic h pollutants are or may be discharged. This term does not include agricultural stormwater discharges and return flows from irrigated agriculture. Pollutant Defined in section 502(6) of the CWA as “dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt and industrial, municipal, and agricultural waste discharged into water.” Pollutant Minimization Program (PMP) PMP means waste minimization and pollution prevention actions that include, but are not limited to, product substitution, waste stream recycling, alternative waste management methods, and education of the public and businesses. The goal of the PMP shall be to reduce all potential sources of a priority pollutant(s) through pollutant minimization (control) strategies, including pollution prevention measures as appropriate, to maintain the effluent concentration at or below the water quality-based effluent limitation. Pollution prevention measures may be particularly appropriate for persistent bioaccumulative priority pollutants where there is evidence that beneficial uses are being impacted. The Central Coast Water Board may consider cost effectiveness when establishing the requirements of a PMP. The completion and implementation of a Pollution Prevention Plan, if required pursuant to California Water Code section 13263.3(d), shall be considered to fulfill the PMP requirements. Pollution Prevention Pollution Prevention means any action that causes a net reduction in the use or generation of a hazardous substance or other pollutant that is discharged into water and includes, but is not limited to, input change, operational improvement, production process change, and product reformulation (as defined in California Water Code section 13263.3). Pollution prevention does not include actions that merely shift a pollutant in wastewater from one environmental medium to another environmental medium, unless clear environmental benefits of such an approach are identified to the satisfaction of the State Water Resources Control Board (State Water Board) or California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board). Publicly Owned Treatment Works (POTW) Facilities owned by a state or municipality that store, treat, recycle, and reclaim municipal sewage or industrial wastes of a liquid nature. Similar facilities that are privately, instead of publicly owned, are included in this definition for purposes of section III of the Toxicity Provisions. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-8 Reasonable Potential A designation used for a waste discharge that is projected or calculated to cause or contribute to an instream excursion above a water quality standard. Regulatory Management Decision (RMD) The decision that represents the maximum allowable error rates and thresholds for toxicity and non-toxicity that would result in an acceptable risk to aquatic life. Replicates Two or more independent organism exposures of the same treatment (i.e., effluent concentration) within a toxicity test. Replicates are typically conducted with separate test chambers and test organisms, each having the same effluent concentration. Reporting Level (RL) The RL is the ML (and its associated analytical method) chosen by the Discharger for reporting and compliance determination from the MLs included in this Order, including an additional factor if applicable as discussed herein. The MLs included in this Orde r correspond to approved analytical methods for reporting a sample result that are selected by the Central Coast Water Board either from Appendix 4 of the State Implementation Policy (SIP) in accordance with section 2.4.2 of the SIP or established in accordance with section 2.4.3 of the SIP. The ML is based on the proper application of method-based analytical procedures for sample preparation and the absence of any matrix interferences. Other factors may be applied to the ML depending o n the specific sample preparation steps employed. For example, the treatment typically applied in cases where there are matrix-effects is to dilute the sample or sample aliquot by a factor of ten. In such cases, this additional factor must be applied to th e ML in the computation of the RL. Response A measured biological effect (e.g., survival, reproduction, growth) as a result of exposure to a stimulus. Routine Monitoring Required monitoring that occurs during a permit term. Source of Drinking Water Any water designated as municipal or domestic supply (MUN) in a Central Coast Water Board Water Quality Control Plan for the Central Coastal Basin (Basin Plan). Species Sensitivity Screening An analysis to determine the single most sensitive species from an array of test species to be used in a single species laboratory test series. Standard Deviation (σ) Standard Deviation is a measure of variability that is calculated as follows: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-9 where: x is the observed value; µ is the arithmetic mean of the observed values; and n is the number of samples. Stormwater As defined at 40 C.F.R. section 122.26(b)(13) (Nov. 16, 1990) which states, ‘Storm water means storm water runoff, snow melt runoff, and surface runoff and drainage.” Test of Significant Toxicity (TST) A statistical approach used to analyze aquatic toxicity test data, as described in section IV.B.1.c of the Toxicity Provisions. Toxicity Identification Evaluation (TIE) Techniques used to identity the unexplained cause(s) of toxic event. A TIE involves selectively removing classes of chemicals through a series of sample manipulations, effectively reducing complex mixtures of chemicals in natural waters to simple components for analysis. Following each manipulation, the toxicity sample is assessed to see whether the toxicant class removed was responsible for the toxicity. Toxicity Reduction Evaluation (TRE) TRE is a study conducted in a step-wise process designed to identify the causative agents of effluent or ambient toxicity, isolate the sources of toxicity, evaluate the effectiveness of toxicity control options, and then confirm the reduction in toxicity. The first steps of the TRE consist of the collection of data relevant to the toxicity, including additional toxicity testing, and an evaluation of facility operations and maintenance practices, and best management practices. A Toxicity Identification Evaluation (TIE) may be required as part of the TRE, if appropriate. (A TIE is a set of procedures to identify the specific chemical(s) responsible for toxicity. These procedures are performed in three phases (characterization, identification, and confirmation) using aquatic organism toxicity tests.) Toxicity Provisions Refers to State Policy for Water Quality Control: Toxicity Provisions (adopted in 2020 and revised in 2021) of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California . CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT B-MAP B-1 B. ATTACHMENT B – MAP CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-1 C. ATTACHMENT C – FLOW SCHEMATIC CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-2 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-1 D. ATTACHMENT D – STANDARD PROVISIONS 1. STANDARD PROVISIONS – PERMIT COMPLIANCE 1.1. Duty to Comply 1.1.1. The Discharger must comply with all terms, requirements, and conditions of this Order. Any noncompliance constitutes a violation of the Clean Water Act (CWA) and the California Water Code (Water Code) and is grounds for enforcement action; permit termination, revocation and reissuance, or modification; denial of a permit renewal application; or a combination thereof. (40 Code of Federal Regulations (C.F.R.) 122.41(a); Water Code sections 13261, 13263, 13265, 13268, 13000, 13001, 13304, 13350, 13385.) 1.1.2. The Discharger shall comply with effluent standards or prohibitions established under Section 307(a) of the CWA for toxic pollutants within the time provided in the regulations that establish these standards or prohibitions, even if this Order has not yet been modified to incorporate the requirement. (40 C.F.R. 122.41(a)(1).) 1.2. Need to Halt or Reduce Activity Not a Defense It shall not be a defense for a Discharger in an enforcement action that it would have been necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this Order. (40 C.F.R. 122.41(c).) 1.3. Duty to Mitigate The Discharger shall take all reasonable steps to minimize or prevent any discharge in violation of this Order that has a reasonable likelihood of adversely affecting human health or the environment. (40 C.F.R. 122.41(d).) 1.4. Proper Operation and Maintenance The Discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the Discharger to achieve compliance with the conditions of this Order. Proper operation and maintenance also include adequate laboratory controls and appropriate quality assurance procedures. This provision requires the operation of backup or auxiliary facilities or similar systems that are installed by a Discharger only when necessary to achieve compliance with the conditions of this Order. (40 C.F.R. 122.41(e).) 1.5. Property Rights 1.5.1. This Order does not convey any property rights of any sort or any exclusive privileges. (40 C.F.R. 122.41(g).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-2 1.5.2. The issuance of this Order does not authorize any injury to persons or property or invasion of other private rights, or any infringement of state or local law or regulations. (40 C.F.R. 122.5(c).) 1.6. Inspection and Entry The Discharger shall allow the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board), State Water Resources Control Board (State Water Board), United States Environmental Protection Agency (U.S. EPA), and/or their authorized representatives (including an authorized contractor acting as their representative), upon the presentation of credentials and other documents, as may be required by law, to (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i); Water Code sections 13267, 13383): 1.6.1. Enter upon the Discharger's premises where a regulated facility or activity is located or conducted, or where records are kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(i); 40 C.F.R. 122.41(i)(1); Water Code sections 13267, 13383); 1.6.2. Have access to and copy, at reasonable times, any records that must be kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(2); Water Code sections 13267, 13383); 1.6.3. Inspect and photograph, at reasonable times, any facilities, equipment (including monitoring and control equipment), practices, or operations regulated or required under this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(3); Water Code sections 13267, 13383); and 1.6.4. Sample or monitor, at reasonable times, for the purposes of assuring Order compliance or as otherwise authorized by the CWA or the Water Code, any substances or parameters at any location. (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i)(4); Water Code sections 13267, 13383.) 1.7. Bypass 1.7.1. Definitions 1.7.1.1. “Bypass” means the intentional diversion of waste streams from any portion of a treatment facility. (40 C.F.R. 122.41(m)(1)(i).) 1.7.1.2. “Severe property damage” means substantial physical damage to property, damage to the treatment facilities, which causes them to become inoperable, or substantial and permanent loss of natural resources that can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production. (40 C.F.R. 122.41(m)(1)(ii).) 1.7.2. Bypass not exceeding limitations. The Discharger may allow any bypass to occur which does not cause exceedances of effluent limitations, but only if it is for essential maintenance to assure efficient operation. These bypasses are not subject to the provisions listed in Standard Provisions – Permit Compliance 1.7.3, 1.7.4, and 1.7.5 below. (40 C.F.R. 122.41(m)(2).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-3 1.7.3. Prohibition of bypass. Bypass is prohibited, and the Central Coast Water Board may take enforcement action against a Discharger for bypass, unless (40 C.F.R. 122.41(m)(4)(i)): 1.7.3.1. Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage (40 C.F.R. 122.41(m)(4)(i)(A)); 1.7.3.2. There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass that occurred during normal periods of equipment downtime or preventive maintenance (40 C.F.R. 122.41(m)(4)(i)(B)); and 1.7.3.3. The Discharger submitted notice to the Central Coast Water Board as required under Standard Provisions – Permit Compliance 1.7.5 below. (40 C.F.R. 122.41(m)(4)(i)(C).) 1.7.4. The Central Coast Water Board may approve an anticipated bypass, after considering its adverse effects, if the Central Coast Water Board determines that it will meet the three conditions listed in Standard Provisions – Permit Compliance 1.7.3 above. (40 C.F.R. 122.41(m)(4)(ii).) 1.7.5. Notice 1.7.5.1. Anticipated bypass. If the Discharger knows in advance of the need for a bypass, it shall submit prior notice, if possible, at least 10 days before the date of the bypass. The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part127. (40 C.F.R. 122.41(m)(3)(i).) 1.7.5.2. Unanticipated bypass. The Discharger shall submit a notice of an unanticipated bypass as required in Standard Provisions - Reporting 5.5 below (24-hour notice). The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(m)(3)(ii).) 1.8. Upset Upset means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the Discharger. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. (40 C.F.R. 122.41(n)(1).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-4 1.8.1. Effect of an upset. An upset constitutes an affirmative defense to an action brought for noncompliance with such technology-based permit effluent limitations if the requirements of Standard Provisions – Permit Compliance 1.8.2 below are met. No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review. (40 C.F.R. 122.41(n)(2).) 1.8.2 Conditions necessary for a demonstration of upset. A Discharger who wishes to establish the affirmative defense of upset shall demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that (40 C.F.R. 122.41(n)(3)): 1.8.2.1. An upset occurred and that the Discharger can identify the cause(s) of the upset (40 C.F.R. 122.41(n)(3)(i)); 1.8.2.2. The permitted facility was, at the time, being properly operated (40 C.F.R. 122.41(n)(3)(ii)); 1.8.2.3. The Discharger submitted notice of the upset as required in Standard Provisions – Reporting 5.5.2.2 below (24-hour notice) (40 C.F.R. 122.41(n)(3)(iii)); and 1.8.2.4. The Discharger complied with any remedial measures required under Standard Provisions – Permit Compliance 1.3 above. (40 C.F.R. 122.41(n)(3)(iv).) 1.8.3. Burden of proof. In any enforcement proceeding, the Discharger seeking to establish the occurrence of an upset has the burden of proof. (40 C.F.R. 122.41(n)(4).) 2. STANDARD PROVISIONS – PERMIT ACTION 2.1. General This Order may be modified, revoked and reissued, or terminated for cause. The filing of a request by the Discharger for modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not stay any Order condition. (40 C.F.R. 122.41(f).) 2.2. Duty to Reapply If the Discharger wishes to continue an activity regulated by this Order after the expiration date of this Order, the Discharger must apply for and obtain a new permit. (40 C.F.R. 122.41(b).) 2.3. Transfers This Order is not transferable to any person except after notice to the Central Coast Water Board. The Central Coast Water Board may require modification or revocation and reissuance of the Order to change the name of the Discharger and incorporate such other requirements as may be necessary under the CWA and the Water Code. (40 C.F.R. 122.41(l)(3), 122.61.) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-5 3. STANDARD PROVISIONS – MONITORING 3.1. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. (40 C.F.R. 122.41(j)(1).) 3.2. Monitoring must be conducted according to test procedures approved under 40 C.F.R. part 136 for the analyses of pollutants unless another method is required under 40 C.F.R. chapter 1, subchapter N. Monitoring must be conducted according to sufficiently sensitive test methods approved under 40 C.F.R. part 136 for the analysis of pollutants or pollutant parameters or as required under 40 C.F.R. chapter 1, subchapter N. For the purposes of this paragraph, a method is sufficiently sensitive when: 3.2.1. The method minimum level (ML) is at or below the level of the most stringent effluent limitation established in the permit for the measured pollutant or pollutant parameter, and either the method ML is at or below the level of the most stringent applicable water quality criterion for the measured pollutant or pollutant parameter or the method ML is above the applicable water quality criterion but the amount of the pollutant or pollutant parameter in the facility’s discharge is high enough that the method detects and quantifies the level of the pollutant or pollutant parameter in the discharge; or 3.2.2. The method has the lowest ML of the analytical methods approved under 40 C.F.R. part 136 or required under 40 C.F.R. chapter 1, subchapter N for the measured pollutant or pollutant parameter. In the case of pollutants or pollutant parameters for which there are no approved methods under 40 C.F.R. part 136 , or otherwise required under 40 C.F.R. chapter 1, subchapter N, monitoring must be conducted according to a test procedure specified in this Order for such pollutants or pollutant parameters. (40 C.F.R. 122.21(e)(3), 122.41(j)(4), 122.44(i)(1)(iv).) 4. STANDARD PROVISIONS – RECORDS 4.1. The Discharger shall retain records of all monitoring information , including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation, copies of all reports required by this Order, and records of all data used to complete the application for this Order, fo r a period of at least three (3) years from the date of the sample, measurement, report or application. This period may be extended by request of the Central Coast Water Board Executive Officer at any time. (40 C.F.R. 122.41(j)(2).) 4.2. Records of monitoring information shall include: 4.2.1. The date, exact place, and time of sampling or measurements (40 C.F.R. 122.41(j)(3)(i)); 4.2.2. The individual(s) who performed the sampling or measurements (40 C.F.R. 122.41(j)(3)(ii)); 4.2.3. The date(s) analyses were performed (40 C.F.R. 122.41(j)(3)(iii)); CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-6 4.2.4. The individual(s) who performed the analyses (40 C.F.R. 122.41(j)(3)(iv)); 4.2.5. The analytical techniques or methods used (40 C.F.R. 122.41(j)(3)(v)); and 4.2.6. The results of such analyses. (40 C.F.R. 122.41(j)(3)(vi).) 4.3. Claims of confidentiality for the following information will be denied (40 C.F.R. 122.7(b)): 4.3.1. The name and address of any permit applicant or Discharger (40 C.F.R. 122.7(b)(1)); and 4.3.2. Permit applications and included attachments, permits, and effluent data. (40 C.F.R. 122.7(b)(2).) 5. STANDARD PROVISIONS – REPORTING 5.1. Duty to Provide Information The Discharger shall furnish to the Central Coast Water Board, State Water Board, or U.S. EPA within a reasonable time, any information which the Central Coast Water Board, State Water Board, or U.S. EPA may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this Order or to determine compliance with this Order. Upon request, the Discharger shall also furnish to the Central Coast Water Board, State Water Board, or U.S. EPA copies of records required to be kept by this Order. (40 C.F.R. 122.41(h); Water Code sections 13267, 13383.) 5.2. Signatory and Certification Requirements 5.2.1. All applications, reports, or information submitted to the Central Coast Water Board, State Water Board, and/or U.S. EPA shall be signed and certified in accordance with Standard Provisions – Reporting 5.2.2, 5.2.3, 5.2.4, 5.2.5, and 5.2.6 below. (40 C.F.R. 122.41(k).) 5.2.2. All permit applications shall be signed by a responsible corporate officer. For the purpose of this section, a responsible corporate officer means: (i) A president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy- or decision- making functions for the corporation, or (ii) the manager of one or more manufacturing, production, or operating facilities, provided, the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmenta l compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures. (40 C.F.R. 122.22(a)(1).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-7 5.2.3. All reports required by this Order and other information requested by the Central Coast Water Board, State Water Board, or U.S. EPA shall be signed by a person described in Standard Provisions – Reporting 5.2.2 above, or by a duly authorized representative of that person. A person is a duly authorized representative only if: 5.2.3.1. The authorization is made in writing by a person described in Standard Provisions – Reporting 5.2.2 above (40 C.F.R. 122.22(b)(1)); 5.2.3.2. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the company. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.) (40 C.F.R. 122.22(b)(2)); and 5.2.3.3. The written authorization is submitted to the Central Coast Water Board and State Water Board. (40 C.F.R. 122.22(b)(3).) 5.2.4. If an authorization under Standard Provisions – Reporting 5.2.3 above is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of Standard Provisions – Reporting 5.2.3 above must be submitted to the Central Coast Water Board and State Water Board prior to or together with any reports, information, or applications, to be signed by an authorized representative. (40 C.F.R. 122.22(c).) 5.2.5. Any person signing a document under Standard Provisions – Reporting 5.2.2 or 5.2.3 above shall make the following certification: “I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.” (40 C.F.R. 122.22(d).) 5.2.6. Any person providing the electronic signature for documents described in Standard Provisions – 5.2.1, 5.2.2, or 5.2.3 that are submitted electronically shall meet all relevant requirements of Standard Provisions – Reporting 5.2, and shall ensure that all relevant requirements of 40 C.F.R. part 3 (Cross-Media Electronic Reporting) and 40 C.F.R. part 127 (NPDES Electronic Reporting Requirements) are met for that submission. (40 C.F.R 122.22(e).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-8 5.3. Monitoring Reports 5.3.1. Monitoring results shall be reported at the intervals specified in the Monitoring and Reporting Program (Attachment E) in this Order. (40 C.F.R. 122.41(l)(4).) 5.3.2. Monitoring results must be reported on a Discharge Monitoring Report (DMR) form or forms provided or specified by the Central Coast Water Board or State Water Board. All reports and forms must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 and comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(l)(4)(i).) 5.3.3. If the Discharger monitors any pollutant more frequently than required by this Order using test procedures approved under 40 C.F.R. part 136, or another method required for an industry-specific waste stream under 40 C.F.R. chapter 1, subchapter N, the results of such monitoring shall be included in the calculation and reporting of the data submitted in the DMR or reporting form specified by the Central Coast Water Board or State Water Board. (40 C.F.R. 122.41(l)(4)(ii).) 5.3.4. Calculations for all limitations, which require averaging of measurements, shall utilize an arithmetic mean unless otherwise specified in this Order. (40 C.F.R. 122.41(l)(4)(iii).) 5.4. Compliance Schedules Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule of this Order, shall be submitted no later than 14 days following each schedule date. (40 C.F.R. 122.41(l)(5).) 5.5. Twenty-Four Hour Reporting 5.5.1. The Discharger shall report any noncompliance which may endanger health or the environment. Any information shall be provided orally within 24 hours from the time the Discharger becomes aware of the circumstances. A report shall also be provided within five (5) days of the time the Discharger becomes aware of the circumstances. The report shall contain a description of the noncompliance and its cause; the period of noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports must include the data described above (with the exception of time of discovery) as well as the type of event (i.e., combined sewer overflow, sanitary sewer overflow, or bypass event), type of overflow structure (e.g., manhole, combined sewer overflow outfall), discharge volume untreated by the treatment works treating domestic sewage, types of human health and environmental impacts of the event, and whether the noncompliance was related to wet weather. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-9 As of December 21, 2023, all reports related to combined sewer overflows, sanitary sewer overflows, or bypass events must be submitted to the Central Coast Water Board and must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 The reports shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(6)(i).) 5.5.2. The following shall be included as information that must be reported within 24 hours: 5.5.2.1. Any unanticipated bypass that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(A).) 5.5.2.2. Any upset that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.5.3. The Central Coast Water Board may waive the above required written report on a case-by-case basis if an oral report has been received within 24 hours. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.6. Planned Changes The Discharger shall give notice to the Central Coast Water Board as soon as possible of any planned physical alterations or additions to the permitted facility. Notice is required under this provision only when (40 C.F.R. 122.41(l)(1)): 5.6.1. The alteration or addition to a permitted facility may meet one of the criteria for determining whether a facility is a new source in section 122.29(b) (40 C.F.R. 122.41(l)(1)(i)); or 5.6.2. The alteration or addition could significantly change the nature or increase the quantity of pollutants discharged. This notification applies to pollutants that are not subject to effluent limitations in this Order. (40 C.F.R. 122.41(l)(1)(ii).); or 5.7. Anticipated Noncompliance The Discharger shall give advance notice to the Central Coast Water Board of any planned changes in the permitted facility or activity that may result in noncompliance with this Order’s requirements. (40 C.F.R. 122.41(l)(2).) 5.8. Other Noncompliance The Discharger shall report all instances of noncompliance not reported under Standard Provisions – Reporting 5.3, 5.4, and 5.5 above at the time monitoring reports are submitted. The reports shall contain the information listed in Standard Provision – Reporting 5.5 above. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports shall contain the information described in Standard Provision – Reporting 5.5 and the applicable required data in appendix A to 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-10 related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(7).) 5.9 Other Information When the Discharger becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or in any report to the Central Coast Water Board, State Water Board, or U.S. EPA, the Discharger shall promptly submit such facts or information. (40 C.F.R. 122.41(l)(8).) 5.10. Initial Recipient for Electronic Reporting Data The owner, operator, or the duly authorized representative is required to electronically submit NPDES information specified in appendix A to 40 C.F.R. part 127 to the initial recipient defined in 40 C.F.R. section 127.2(b). U.S. EPA will identify and publish the list of initial recipients on its website and in the Federal Register, by state and by NPDES data group [see 40 C.F.R. 127.2(c)]. U.S. EPA will update and maintain this listing. (40 C.F.R. 122.41(l)(9).) 6. STANDARD PROVISIONS – ENFORCEMENT 6.1. The Central Coast Water Board is authorized to enforce the terms of this permit under several provisions of the Water Code, including, but not limited to, sections 13268, 13350, 13385, 13386, and 13387. 7. ADDITIONAL PROVISIONS – NOTIFICATION LEVELS 7.1. Non-Municipal Facilities Existing manufacturing, commercial, mining, and silvicultural Dischargers shall notify the Central Coast Water Board as soon as they know or have reason to believe (40 C.F.R. 122.42(a)): 7.1.1. That any activity has occurred or will occur that would result in the discharge, on a routine or frequent basis, of any toxic pollutant that is not limited in this Order, if that discharge will exceed the highest of the following "notification levels" (40 C.F.R. 122.42(a)(1)): 7.1.1.1. 100 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(1)(i)); 7.1.1.2. 200 μg/L for acrolein and acrylonitrile; 500 μg/L for 2,4 dinitrophenol and 2-methyl 4,6 dinitrophenol; and 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(1)(ii)); 7.1.1.3. Five (5) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(1)(iii)); or 7.1.1.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(1)(iv).) 7.1.2. That any activity has occurred or will occur that would result in the discharge, on a non-routine or infrequent basis, of any toxic pollutant that is not limited in this CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-11 Order, if that discharge will exceed the highest of the following “notification levels" (40 C.F.R. 122.42(a)(2)): 7.1.2.1. 500 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(2)(i)); 7.1.2.2. 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(2)(ii)); 7.1.2.3. Ten (10) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(2)(iii)); or 7.1.2.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(2)(iv).) 7.2 Publicly Owned Treatment Works (POTWs) All POTWs shall provide adequate notice to the Central Coast Water Board of the following (40 C.F.R. 122.42(b)): 7.2.1. Any new introduction of pollutants into the POTW from an indirect discharger that would be subject to sections 301 or 306 of the CWA if it were directly discharging those pollutants (40 C.F.R. 122.42(b)(1)); and 7.2.2. Any substantial change in the volume or character of pollutants being introduced into that POTW by a source introducing pollutants into the POTW at the time of adoption of the Order. (40 C.F.R. 122.42(b)(2).) 7.2.3. Adequate notice shall include information on the quality and quantity of effluent introduced into the POTW as well as any anticipated impact of the change on the quantity or quality of effluent to be discharged from the POTW. (40 C.F.R. 122.42(b)(3).) 8. CENTRAL COAST WATER BOARD STANDARD PROVISIONS 8.1. Central Coast Standard Provision – Prohibitions 8.1.1. Introduction of “incompatible wastes” to the treatment system is prohibited. 8.1.2. Discharge of high-level radiological waste and of radiological, chemical, and biological warfare agents is prohibited. 8.1.3. Discharge of “toxic pollutants” in violation of effluent standards and prohibitions established under section 307(a) of the CWA is prohibited. 8.1.4. Discharge of sludge, sludge digester or thickener supernatant, and sludge drying bed leachate to drainageways, surface waters, or the ocean is prohibited. 8.1.5. Introduction of pollutants into the collection, treatment, or disposal system by and “indirect discharger” that: 8.1.5.1. Inhibit or disrupt the treatment process, system operation, or the eventual use or disposal of sludge; or, 8.1.5.2. Flow through the system to the receiving water untreated; and, 8.1.5.3. Cause or “significantly contribute” to a violation of any requirement of this Order, is prohibited. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-12 8.1.6. Introduction of “pollutant free” wastewater to the collection, treatment, and disposal system in amounts that threaten compliance with this order is prohibited. 8.2. Central Coast Standard Provisions 8.2.1. Collection, treatment, and discharge of waste shall not create a nuisance or pollution, as defined by Water Code section 13050. 8.2.2. All facilities used for transport or treatment of wastes shall be adequately protected from inundation and washout as the result of a 100-year frequency flood. 8.2.3. Operation of collection, treatment, and disposal systems shall be in a manner that precludes public contact with wastewater. 8.2.4. Collected screenings, sludges, and other solids removed from liquid wastes shall be disposed in a manner approved by the Executive Officer. 8.2.5. Publicly owned wastewater treatment plans shall be supervised and operated by persons possessing certificates of appropriate grade pursuant to title 23 of the California Administrative Code. 8.2.6. After notice and opportunity for a hearing, this order may be terminated for cause, including, but not limited to: 8.2.6.1. Violation of any term or condition contained in this order; 8.2.6.2. Obtaining this order by misrepresentation, or by failure to disclose fully all relevant facts; 8.2.6.3. A change in any condition or endangerment to human health or environment that requires a temporary or permanent reduction or elimination of the authorized discharge; and, 8.2.6.4. A substantial change in character, location, or volume of the discharge. 8.2.7. Provisions of this permit are severable. If any provision of the permit is found invalid, the remainder of the permit shall not be affected. 8.2.8. After notice and opportunity for hearing, this order may be modified or revoked and reissued for cause, including: 8.2.8.1. Promulgation of a new or revised effluent standard or limitation; 8.2.8.2. A material change in character, location, or volume of the discharge; 8.2.8.3. Access to new information that affects the germs of the permit, including applicable schedules; 8.2.8.4. Correction of technical mistakes or mistaken interpretations of law; and, 8.2.8.5. Other causes set forth under Sub -part D of 40 C.F.R. part 122. 8.2.9. Safeguards shall be provided to ensure maximal compliance with all terms and conditions of this permit. Safeguards shall include preventative and contingency plans and may also include alternative power sources, stand-by generators, retention capacity, operative procedures, or other precautions. Preventative and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-13 contingency plans for controlling and minimizing the effect of accidental discharges shall: 8.2.9.1. Identify possible situations that could cause “upset,” “overflow,” or “bypass,” or other noncompliance. (Loading and storage areas, power outage, waste treatment unit outage, and failure of process equipment, tanks and pipes should be considered). 8.2.9.2. Evaluate the effectiveness of present facilities and procedures and describe procedures and steps to minimize or correct any adverse environmental impact resulting from noncompliance with the permit. 8.2.10. Physical Facilities shall be designed and constructed according to accepted engineering practice and shall be capable of full compliance with this order when properly operated and maintained. Proper operation and maintenance shall be described in an Operation and Maintenance Manual. Facilities shall be accessible during the wet-weather season. 8.2.11. The discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) that are installed or used by the discharger to achieve compliance with the conditions of this order. Electrical and mechanical equipment shall be maintained in accordance with appropriate practices and standards, such as NFPA 70B, Recommended Practice for Electrical Equipment Maintenance; NFPA 70E, Standard for Electrical Safety in the Workplace; ANSI/NETA MTS Standard for Maintenance: Testing Specifications for Electrical Power Equipment and Systems, or procedures established by insurance companies or industry resources. 8.2.12. If the discharger’s facilities are equipped with SCADA or other systems that implement wireless, remote operation, the discharger should implement appropriate safeguards against unauthorized access to the wireless systems. Standards such as NIST SP 800-53, Recommended Security Controls for Federal Information Systems, can provide guidance. 8.2.13. Production and use of reclaimed water is subject to the approval of the Central Coast Water Board. Production and use of reclaimed water shall be in conformance with recycling criteria established in chapter 3, title 22, of the California Administrative Code and chapter 7, division 7, of the Water Code. An engineering report pursuant to section 60323, title 22, of the California Administrative Code is required and a waiver or water recycling requirements from the Central Coast Water Board is required before reclaimed water is supplied for any use, or to any user, not specifically identified and approved either in this Order or another order issued by the Central Coast Water Board. 8.3. Central Coast Standard Provisions – General Monitoring Requirements 8.3.1. If results of monitoring a pollutant appear to violate effluent limitations based on a weekly, monthly, 30-day, or six-month period, but compliance or non-compliance cannot be validated because sampling is too infrequent, the frequency of sampling shall be increased to validate the test within the next monitoring period. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-14 The increased frequency shall be maintained until the Executive Officer agrees the original monitoring frequency may be resumed. For example, if copper is monitored annually and results exceed the six -month median numerical effluent limitation in the permit, monitoring of copper must be increased to a frequency of at least once every two months (Central Coast Standard Provisions – Definitions 1.7.13.). If suspended solids are monitored weekly and results exceed the weekly average numerical limit in the permit, monitoring of suspended solids must be increased to at least four (4) samples every week (Central Coast Standard Provisions – Definitions 1.7.14.). 8.3.2. Water quality analyses performed in order to monitor compliance with this permit shall be by a laboratory certified by the Division of Drinking Water for the constituent(s) being analyzed. Bioassay(s) performed in order to monitor compliance with this permit shall be in accord with guidelines approved by the State Water Board and the California Department of Fish and Wildlife. If the laboratory used or proposed for use by the discharger is not certified by the Division of Drinking Water or, where appropriate, the Department of Fish and Wildlife due to restrictions in the State's laboratory certification program, the discharger shall be considered in compliance with this provision provided: 8.3.2.1. Data results remain consistent with results of samples analyzed by the Central Coast Water Board; 8.3.2.2. A quality assurance program is used at the laboratory, including a manual containing steps followed in this program that is available for inspections by the staff of the Central Coast Water Board; and, 8.3.2.3. Certification is pursued in good faith and obtained as soon as possible after the program is reinstated. 8.3.3. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. Samples shall be taken during periods of peak loading conditions. Influent samples shall be samples collected from the combined flows of all incoming wastes, excluding recycled wastes. Effluent samples shall be samples collected downstream of the last treatment unit and tributary flow and upstream of any mixing with receiving waters. 8.3.4. All monitoring instruments and devices used by the discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. 8.4. Central Coast Standard Provisions – General Reporting Requirements 8.4.1. Reports of marine monitoring surveys conducted to meet receiving water monitoring requirements of the Monitoring and Reporting Program shall include at least the following information: 8.4.1.1. A description of climatic and receiving water characteristics at the time of sampling (weather observations, floating debris, discoloration, wind speed and direction, swell or wave action, time of sampling, tide height, etc.). CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-15 8.4.1.2. A description of sampling stations, including differences unique to each station (e.g., station location, grain size, rocks, shell litter, calcareous worm tubes, evident life, etc.). 8.4.1.3. A description of the sampling procedures and preservation sequence used in the survey. 8.4.1.4. A description of the exact method used for laboratory analysis. In general, analysis shall be conducted according to Central Coast Standard Provisions – 8.3.1 above, and Federal Standard Provision – Monitoring 3.2. However, variations in procedure are acceptable to accommodate the special requirements of sediment analysis. All such variations must be reported with the test results. 8.4.1.5. A brief discussion of the results of the survey. The discussion shall compare data from the control station with data from the outfall stations. All tabulations and computations shall be explained. 8.4.2. Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule shall be submitted within 14 days following each scheduled date unless otherwise specified within the permit. If reporting noncompliance, the report shall include a description of the reason, a description and schedule of tasks necessary to achieve compliance, and an estimated date for achieving full compliance. A second report shall be submitted within 14 days of full compliance. 8.4.3. The Discharger shall file a Report of Waste Discharge or secure a waiver from the Executive Officer at least 180 days before making any material change or proposed change in the character, location, or plume of the discharge. 8.4.4. Within 120 days after the Discharger discovers, or is notified by the Central Coast Water Board, that monthly average daily flow will or may reach design capacity of waste treatment and/or disposal facilities within four (4) years, the Discharger shall file a written report with the Central Coast Water Board. The report shall include: 8.4.4.1. The best estimate of when the monthly average daily dry weather flow rate will equal or exceed design capacity; and, 8.4.4.2. A schedule for studies, design, and other steps needed to provide additional capacity for waste treatment and/or disposal facilities before the waste flow rate equals the capacity of present units. In addition to complying with Federal Standard Provision – Reporting 5.2, the required technical report shall be prepared with public participation and reviewed, approved and jointly submitted by all planning and building departments having jurisdiction in the area served by the waste collection, treatment, or disposal facilities. 8.4.5. All Dischargers shall submit reports electronically to the: California Regional Water Quality Control Board Central Coast Region CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-16 centralcoast@waterboards.ca.gov 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 In addition, Dischargers with designated major discharges shall submit a copy of each document to: Regional Administrator U.S. EPA, Region 9 Attention: CWA Standards and Permits Office (WTR-5) 75 Hawthorne Street San Francisco, California 94105 8.4.6. Transfer of control or ownership of a waste discharge facility must be preceded by a notice to the Central Coast Water Board at least 30 days in advance of the proposed transfer date. The notice must include a written agreement between the existing Discharger and proposed Discharger containing specific date for transfer of responsibility, coverage, and liability between them. Whether a permit may be transferred without modification or revocation and reissuance is at the discretion of the Board. If permit modification or revocation and reissuance is necessary, transfer may be delayed 180 days after the Central Coast Water Board's receipt of a complete permit application. Please also see Federal Standard Provision – Permit Action 2.3. 8.4.7. Except for data determined to be confidential under CWA section 308 (excludes effluent data and permit applications), all reports prepared in accordance with this permit shall be available for public inspection at the office of the Central Coast Water Board or Regional Administrator of U.S. EPA. Please also see Federal Standard Provision – Records 4.3. 8.4.8. By February 1st of each year, the discharger shall submit an annual report to the Central Coast Water Board. The report shall contain the following: 8.4.8.1. Both tabular and graphical summaries of the monitoring data obtained during the previous year. 8.4.8.2. A discussion of the previous year’s compliance record and corrective actions taken, or which may be needed, to bring the discharger into full compliance. 8.4.8.3. An evaluation of wastewater flows with projected flow rate increases over time and the estimated date when flows will reach facility capacity. 8.4.8.4. A discussion of operator certification and a list of current operating personnel and their grades of certification. 8.4.8.5. The date of the facility’s Operation and Maintenance Manual (including contingency plans as described in Provision 8.2.9), the date the manual was last reviewed, and whether the manual is complete and valid for the current facility. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-17 8.4.8.6. A discussion of the laboratories used by the discharger to monitor compliance with effluent limits and a summary of performance relative to section 8.3, General Monitoring Requirements. 8.4.8.7. If the facility treats industrial or domestic wastewater and there is no provision for periodic sludge monitoring in the Monitoring and Reporting Program, the report shall include a summary of sludge quantities, analyses of its chemical and moisture content, and its ultimate destination. 8.4.8.8. If appropriate, the report shall also evaluate the effectiveness of the local source control or pretreatment program using the State Water Board's "Guidelines for Determining the Effectiveness of Local Pretreatment Program." 8.5. Central Coast Standard Provisions – General Pretreatment Provisions 8.5.1. Discharge of pollutants by "indirect dischargers” in specific industrial sub- categories (appendix C, 40 C.F.R. part 403), where categorical pretreatment standards have been established, or are to be established, (according to 40 C.F.R. chapter 1, subchapter N), shall comply with the appropriate pretreatment standards: 8.5.1.1. By the date specified therein; 8.5.1.2. Within three (3) years of the effective date specified therein, but in no case later than July 1, 1984; or, 8.5.1.3. If a new indirect discharger, upon commencement of discharge. 8.6. Central Coast Standard Provision – Enforcement 8.6.1. Any person failing to file a Report of Waste Discharge or other report as required by this permit shall be subject to a civil penalty not to exceed $5,000 per day. 8.6.2. Upon reduction, loss, or failure of the treatment facility, the Discharger shall, to the extent necessary to maintain compliance with this permit, control production or all discharges, or both, until the facility is restored or an alternative method of treatment is provided. 8.7. Central Coast Standard Provisions – Definitions (Not otherwise included in Attachment A to this Order) 8.7.1. A “composite sample" is a combination of no fewer than eight (8) individual samples obtained at equal time intervals (usually hourly) over the specified sampling (composite) period. The volume of each individual sample is proportional to the flow rate at the time of sampling. The period shall be specified in the Monitoring and Reporting Program ordered by the Executive Officer. 8.7.2. “Daily Maximum” limit means the maximum acceptable concentration or mass emission rate of a pollutant measured during a calendar day or during any 24 - hour period reasonably representative of the calendar day for purposes of sampling. It is normally compared with results based on "composite samples” except for ammonia, total chlorine, phenolic compounds, and toxicity CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-18 concentration. For all exceptions, comparisons will be made with results from a “grab sample”. 8.7.3. “Discharger", as used herein, means, as appropriate: (1) the Discharger, (2) the local sewering entity (when the collection system is not owned and operated by the Discharger), or (3) "indirect discharger" (where "Discharger" appears in the same paragraph as "indirect discharger”, it refers to the discharger.) 8.7.4. “Duly Authorized Representative" is one where: 8.7.4.1. The authorization is made in writing by a person described in the signatory paragraph of Federal Standard Provision 5.2.; 8.7.4.2. The authorization specifies either an individual or the occupant of a position having either responsibility for the overall operation of the regulated facility, such as the plant manager, or overall responsibility for environmental matters of the company; and, 8.7.4.3. The written authorization was submitted to the Central Coast Water Board. 8.7.5. A "grab sample" is defined as any individual sample collected in less than 15 minutes. "Grab samples” shall be collected during peak loading conditions, which may or may not be during hydraulic peaks. It is used primarily in determining compliance with the daily maximum limits identified in Central Coast Standard Provision – Provision 8.7.2. and instantaneous maximum limits. 8.7.6. "Hazardous substance” means any substance designated under 40 C.F.R. part 116 pursuant to section 311 of the CWA. 8.7.7. "Incompatible wastes” are: 8.7.7.1. Wastes which create a fire or explosion hazard in the treatment works; 8.7.7.2. Wastes which will cause corrosive structural damage to treatment works, but in no case wastes with a pH lower than 5.0 unless the works is specifically designed to accommodate such wastes; 8.7.7.3. Solid or viscous wastes in amounts which cause obstruction to flow in sewers, or which cause other interference with proper operation of treatment works; 8.7.7.4. Any waste, including oxygen demanding pollutants (BOD, etc.), released in such volume or strength as to cause inhibition or disruption in the treatment works and subsequent treatment process upset and loss of treatment efficiency; and, 8.7.7.5. Heat in amounts that inhibit or disrupt biological activity in the treatment works or that raise influent temperatures above 40°C (104°F) unless the treatment works is designed to accommodate such heat. 8.7.8. "Indirect Discharger” means a non-domestic discharger introducing pollutants into a publicly owned treatment and disposal system. 8.7.9. "Log Mean” is the geometric mean. Used for determining compliance of fecal or total coliform populations, it is calculated with the following equation: Log Mean = (C1 x C2 x...x Cn)1/n, CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-19 in which “n" is the number of days samples were analyzed during the period and any "C" is the concentration of bacteria (MPN/100 mL) found on each day of sampling. "n” should be five or more. 8.7.10. “Mass emission rate" is a daily rate defined by the following equations: mass emission rate (lbs/day) = 8.34 x Q x C; and, mass emission rate (kg/day) = 3.79 x Q x C, where “C" (in mg/L) is the measured daily constituent concentration or the average of measured daily constituent concentrations and “Q” (in MGD) is the measured daily flowrate or the average of measured daily flow rates over the period of interest. 8.7.11. The "Maximum Allowable Mass Emission Rate," whether for a month, week, day, or six-month period, is a daily rate determined with the formulas in paragraph 8.7.10, above, using the effluent concentration limit specified in the permit for the period and the average of measured daily flows (up to the allowable flow) over the period. 8.7.12. “Maximum Allowable Six-Month Median Mass Emission Rate" is a daily rate determined with the formulas in Central Coast Standard Provision – Provision 8.7.10, above, using the "six-month Median" effluent limit specified in the permit, and the average of measured daily flows (up to the allowable flow) over a 180-day period. 8.7.13. "Median" is the value below which half the samples (ranked progressively by increasing value) fall. It may be considered the middle value, or the average of two middle values. 8.7.14. "Monthly Average" (or "Weekly Average”, as the case may be) is the arithmetic mean of daily concentrations or of daily mass emission rates over the specified 30-day (or 7-day) period. Average = (X1 + X2 + ... + Xn) / n in which “n" is the number of days samples were analyzed during the period and “X" is either the constituent concentration (mg/l) or mass emission rate (kg/day or lbs/day) for each sampled day. “n" should be four or greater. 8.7.15. "Municipality" means a city, town, borough, county, district, association, or other public body created by or under State law and having jurisdiction over disposal of sewage, industrial waste, or other waste. 8.7.16. "Overflow" means the intentional or unintentional diversion of flow from the collection and transport systems, including pumping facilities. 8.7.17. "Pollutant-free wastewater" means inflow and infiltration, stormwaters, and cooling waters and condensates which are essentially free of pollutants. 8.7.18. "Primary Industry Category" means any industry category listed in 40 C.F.R. part 122, Appendix A. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-20 8.7.19. "Removal Efficiency" is the ratio of pollutants removed by the treatment unit to pollutants entering the treatment unit. Removal efficiencies of a treatment plant shall be determined using “Monthly averages" of pollutant concentrations (C, in mg/l) of influent and effluent samples collected about the same time and the following equation (or its equivalent): 8.7.20. "Severe property damage" means substantial physical damage to property, damage to treatment facilities which causes them to become inoperable, or substantial and permanent loss to natural resources which can reasonably be expected to occur in the absence of a "bypass”. It does not mean economic loss caused by delays in production. 8.7.21. "Sludge" means the solids, residues, and precipitates separated from, or created in, wastewater by the unit processes of a treatment system. 8.7.22. To "significantly contribute" to a permit violation means an "indirect discharger" must: 8.7.22.1. Discharge a daily pollutant loading in excess of that allowed by contract with the Discharger or by Federal, State, or Local law; 8.7.22.2. Discharge wastewater which substantially differs in nature or constituents from its average discharge; 8.7.22.3. Discharge pollutants, either alone or in conjunction with discharges from other sources, which results in a permit violation or prevents sewage sludge use or disposal; or 8.7.22.4. Discharge pollutants, either alone or in conjunction with pollutants from other sources that increase the magnitude or duration of permit violations. 8.7.23. "Toxic Pollutant" means any pollutant listed as toxic under Section 307 (a) (1) of the CWA or under 40 C.F.R. part 122, Appendix D. Violation of maximum daily discharge limitations are subject to 24-hour reporting (Federal Standard Provisions 5.5.). 8.7.24. “Zone of Initial Dilution" means the region surrounding or adjacent to the end of an outfall pipe or diffuser ports whose boundaries are defined through calculation of a plume model verified by the State Water Board. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-1 E. ATTACHMENT E – MONITORING AND REPORTING PROGRAM TABLE OF CONTENTS 1. GENERAL MONITORING PROVISIONS .................................................................E-2 2. MONITORING LOCATIONS ....................................................................................E-3 3. INFLUENT MONITORING REQUIREMENTS ..........................................................E-5 3.1. Monitoring Location INF-001 .................................................................................E-5 4. EFFLUENT MONITORING REQUIREMENTS .........................................................E-5 4.1. Monitoring Location EFF-001 ................................................................................E-5 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS .................................E-9 5.1. Whole Effluent Acute Toxicity Testing ...................................................................E-9 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable .............. E-18 7. RECYCLING MONITORING REQUIREMENTS .................................................... E-18 7.1. Monitoring Location EFF-002 .............................................................................. E-18 8. RECEIVING WATER MONITORING REQUIREMENTS ........................................ E-19 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW- 006, RSW-007, and RSW-008 .............................................................................. E-19 9. OTHER MONITORING REQUIREMENTS ............................................................. E-21 9.1. Biosolids, Monitoring, and Notification – BIO-001 ............................................... E-21 9.2. Pretreatment Monitoring ...................................................................................... E-26 9.3. Salt and Nutrient Management Plan Reporting ................................................... E-29 9.4. Volumetric Monitoring of Wastewater and Recycled Water ................................. E-30 10. REPORTING REQUIREMENTS .......................................................................... E-30 10.1. General Monitoring and Reporting Requirements ............................................. E-30 10.2. Self-Monitoring Reports (SMRs)........................................................................ E-30 10.3. Discharge Monitoring Reports (DMRs) .............................................................. E-34 10.4. Other Reports .................................................................................................... E-34 TABLE OF TABLES Table E-1. Monitoring Station Locations .......................................................................E-3 Table E-2. Influent Monitoring ......................................................................................E-5 Table E-3. Effluent Monitoring at EFF-001 ...................................................................E-6 Table E-4. Approved Test for Acute Toxicity – Fresh Water ...................................... E-10 Table E-5. Approved Tests for Chronic Toxicity – Freshwater ................................... E-14 Table E-6. Recycled Water Monitoring Requirements at EFF-002 ............................. E-18 Table E-7. Receiving Water Monitoring Requirements............................................... E-19 Table E-8. Amount of Biosolids and Frequency of Analysis ....................................... E-21 Table E-9. Biosolids Monitoring Requirements .......................................................... E-22 Table E-10. Monitoring Periods and Reporting Schedule........................................... E-31 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-2 ATTACHMENT E – MONITORING AND REPORTING PROGRAM Section 308 of the federal Clean Water Act (CWA) and sections 122.41(h), (j)-(l), 122.44(i), and 122.48 of title 40 of the Code of Federal Regulations (40 C.F.R.) require that all NPDES permits specify monitoring and reporting requirements. California Water Code sections 13267 and 13383 also authorize the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) to establish monitoring, inspection, entry, reporting, and recordkeeping requirements. This Monitoring and Reporting Program (MRP) establishes monitoring, reporting, and recordkeeping requirements that implement the federal and California laws and/or regulations. 1. GENERAL MONITORING PROVISIONS 1.1. Laboratories analyzing monitoring samples shall be certified by the State Water Resources Control Board (State Water Board), in accordance with the provision of California Water Code section 13176, and must include quality assurance/quality control data with their reports. 1.2. Samples and measurements taken as required herein shall be representative of the volume and nature of the monitored discharge. All samples shall be taken at the monitoring locations specified in this MRP and, unless otherwise specified, before the monitored flow joins or is diluted by any other waste stream, body of water, or substance. Monitoring locations shall not be changed without notification to and approval of the Central Coast Water Board. 1.3. Appropriate flow measurement devices and methods consistent with accepted scientific practices shall be selected and used to ensure the accuracy and reliability of measurements of the volume of monitored discharges. The devices shall be installed, calibrated, and maintained to ensure that the accuracy of the measurements is consistent with the accepted capability of that type of device. Devices selected shall be capable of measuring flows with a maximum deviation of less than ±10 percent from true discharge rates throughout the range of expected discharge volumes. Guidance in selection, installation, calibration, and operation of acceptable flow measurement devices can be obtained from the following references. 1.3.1. A Guide to Methods and Standards for the Measurement of Water Flow, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 421, May 1975, 96 pp. http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication421.pdf 1.3.2. Water Measurement Manual, U.S. Department of Interior, Bureau of Reclamation, Second Edition, Revised Reprint, 1974, 327 pp. https://www.usbr.gov/tsc/techreferences/mands/wmm/index.htm1.3.3. Flow Measurement in Open Channels and Closed Conduits, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 484, October 1977, 982 pp. https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication484v2.pdf CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-3 1.3.3. NPDES Compliance Inspection Manual, Chapter 6 – Flow Measurement, U.S. Environmental Protection Agency (U.S. EPA), Office of Water Enforcement, Publication Number 305-K-17-001, January 2017, 918 pp. https://www.epa.gov/compliance/compliance-inspection-manual-national- pollutant-discharge-elimination-system 1.4. All monitoring instruments and devices used by the Discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. All flow measurement devices shall be calibrated at least once per year to ensure continued accuracy of the devices. 1.5. Monitoring results, including noncompliance, shall be reported at intervals and in a manner specified in this MRP. 1.6. Unless otherwise specified by this MRP, all monitoring shall be conducted according to test procedures established at 40 C.F.R. part 136, Guidelines Establishing Test Procedures for Analysis of Pollutants. All analyses shall be conducted using the lowest practical quantitation limit achievable using the specified methodology. Where effluent limitations are set below the lowest achievable quantitation limits, pollutants not detected at the lowest practical quantitation limits will be considered in compliance with effluent limitations. Analysis for toxic pollutants listed by the California Toxics Rule shall also adhere to guidance and requirements contained in the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (2005) (SIP). 1.7. The Discharger shall ensure that the results of the Discharge Monitoring Report- Quality Assurance (DMR-QA) Study or the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board at the following address: State Water Resources Control Board; Quality Assurance Program Officer; Office of Information Management and Analysis; 1001 I Street, Sacramento, CA 95814 2. MONITORING LOCATIONS The Discharger shall establish the following monitoring locations to demonstrate compliance with the effluent limitations, discharge specifications, and other requirements in this Order: Table E-1. Monitoring Station Locations Discharge Point Name Monitoring Location Name Monitoring Location Description INF-001 Influent wastewater prior to treatment and following all significant inputs to the collection system of untreated wastewater and inflow and infiltration, where representative samples of CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-4 Discharge Point Name Monitoring Location Name Monitoring Location Description wastewater influent can be obtained prior to any plant return flows or treatment processes EFF-001 EFF-001A At a point where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to entering the discharge pipeline to San Luis Obispo Creek: 35.251533°N, 120.676817°W EFF-001B At a point at the end of the discharge pipeline where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to commingling with other waste streams or being discharged into San Luis Obispo Creek: 35.244307°N, 120.680618°W EFF-002 EFF-002 Location where a representative sample of title 22 recycled water can be collected prior to discharge to the recycled water storage tank. Receiving Water RSW-001 At Fox Canyon Road Receiving Water RSW-002 At Mission Receiving Water RSW-003 At Marsh Street Bridge Receiving Water RSW-004 50 feet upstream of effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-005 A location in San Luis Obispo Creek immediately upstream of the confluence with Prefumo Canyon Creek CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-5 Discharge Point Name Monitoring Location Name Monitoring Location Description Receiving Water RSW-006 A location in Prefumo Canyon Creek 50 feet upstream of the confluence with San Luis Obispo Creek Receiving Water RSW-007 Approximately 0.5 miles downstream from effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-008 At Higuera Street Bridge, near US 101 Biosolids BIO-001 Biosolids at the last point in the biosolids handling process where representative samples of residual solids from the treatment process can be obtained 3. INFLUENT MONITORING REQUIREMENTS 3.1. Monitoring Location INF-001 3.1.1. The Discharger shall monitor influent to the facility at INF-001 as below: Table E-2. Influent Monitoring Parameter Units Sample Type Minimum Sampling Frequency Flow Million gallons per day (MGD) Measured 1/Day Biochemical Oxygen Demand 5-day @ 20°C (BOD5)[2] Milligram per liter (mg/L) 24-hour Composite 1/Month[1] Total Suspended Solids (TSS)[2] mg/L 24-hour Composite 1/Month[1] [1] The Discharger shall report the average and maximum daily flows. [2] Collection of BOD5 and TSS samples shall occur on days that effluent samples are collected. BOD shall be monitored in the influent at the same time as it is monitored in the effluent. 4. EFFLUENT MONITORING REQUIREMENTS 4.1. Monitoring Location EFF-001 4.1.1. The Discharger shall monitor effluent discharged at Monitoring Location EFF -001 as specified in Table E-3. Except where specified, all monitoring will be performed at EFF-001A. If more than one analytical test method is listed for a given CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-6 parameter, the Discharger must select from the listed methods and corresponding Minimum Level: Table E-3. Effluent Monitoring at EFF-001 Parameter Units Sample Type Minimum Sampling Frequency Flow MGD Metered 1/Day Instantaneous Maximum Flow MGD Metered 1/Day Maximum Daily Flow Calculated 1/Month Mean Daily Flow MGD Calculated 1/Month Biochemical Oxygen Demand, 5- day (BOD5) mg/L 24-hour Composite 1/Month BOD Mass Emissions Rate pounds per day (lbs/day) Calculated 1/Month BOD5 Percent removal Calculated 1/Month pH[1] standard units Continuous or Grab 1/Day Chlorine, Total Residual[2] mg/L Continuous or Grab Grab samples shall be taken a minimum of twice per day, and within 30 minutes of any excursion above 0.1 mg/L Chlorine Used[2] lbs/day Calculated 1/Day Temperature[1] °C Continuous or Grab 5/Week Total Coliform MPN/100 mL Grab 5/Week Settleable Solids milliliter per liter (ml/L) Grab 1/Week Ammonia (as N) [3] mg/L Grab 1/Week Un-ionized Ammonia (as N) [1] mg/L Calculated 1/Week Total Suspended Solids (TSS) mg/L 24-hr. composite 1/Week TSS Percent removal Calculated 1/Week Turbidity Nephelo- metric Turbidity 24-hr. composite 1/10 days CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-7 Parameter Units Sample Type Minimum Sampling Frequency Units (NTU) Dissolved Oxygen mg/L Grab 1/Month Color Color units Grab 1/Month Oil and Grease mg/L Grab 1/Month Total Kjeldahl Nitrogen (TKN) (as N) mg/L Grab 1/Month Chlorodibromomethane (aka Dibromochloromethane) μg/L 24-hr. composite 1/Month[4] Chloroform μg/L 24-hr. composite 1/Month[4] Dichlorobromomethane μg/L 24-hr. composite 1/Month[4] Methylene Chloride μg/L 24-hr. composite 1/Month[4] Pentachlorophenol μg/L 24-hr. composite 1/Month[4] Nitrate (as N) mg/L Grab 1/Month Nitrite (as N) mg/L Grab 1/Month Methylene Blue Active Substances (MBAS) mg/L 24-hr. composite 1/Month[4] Molybdenum mg/L Grab 1/Month Dissolved Orthophosphate (as P) mg/L Grab 1/Month Total Phosphate (as P) mg/L Grab 1/Month Total Dissolved Solids (TDS) mg/L Grab 1/Month Sodium mg/L Grab 1/Month Chloride mg/L Grab 1/Month Sulfate mg/L Grab 1/Month Hardness (CaCO3)[5] mg/L 24-hr. composite 1/Quarter Boron mg/L Grab 1/Year (in October) Cobalt mg/L Grab 1/Year (in October) Iron mg/L Grab 1/Year (in October) Lithium mg/L Grab 1/Year (in October) Manganese mg/L Grab 1/Year (in October) Vanadium mg/L Grab 1/Year (in October) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-8 Parameter Units Sample Type Minimum Sampling Frequency Acute Toxicity[6] ”Pass/Fail” and % Effect Grab 1/Year Chronic Toxicity[6] “Pass/Fail and % Effect” Grab 1/Month[7] California Toxics Rule (CTR) Pollutants[8], [9] μg/L 24-Hour composite 1/Year (in October) Title 22 Pollutants[10], [11] μg/L 24-Hour composite 1/Year (in October) [1] Temperature and pH are to be measured at the same time the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] Sampling shall be concurrent with sampling of receiving water for ammonia. [4] If no exceedances of the effluent limitation occur for a minimum of 12 consecutive months of monitoring then the frequency of monitoring shall be reduced to quarterly. Subsequently, if an exceedance of the effluent limitation occurs during quarterly monitoring, the monitoring frequency shall return to monthly. The Discharger must notify the Central Coast Water Board of the change in monitoring frequency . [5] Hardness monitoring will occur on the same day and time as the California Toxics Rule (CTR) pollutants to allow for conversion from total recoverable to dissolved for hardness dependent metals. [6] Whole effluent acute and chronic toxicity monitoring shall be conducted according to the requirements established in sections 5.1 and 5.2, respectively, of this MRP. [7] Once per year, in October, chronic toxicity monitoring must be performed at EFF- 001B instead of at EFF-001A. [8] The California Toxics Rule (CTR) pollutants are those listed by the CTR at 40 C.F.R. 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). The Discharger shall instruct its analytical laboratory to establish calibration standards so that the Minimum Levels (MLs) presented in Appendix 4 of the SIP are the lowest calibration standards. The Discharger and its analytical laboratory shall select MLs which are below applicable water quality criteria of the CTR; and when applicable water quality criteria are below all MLs, the Discharger and its analytical laboratory shall select the lowest ML. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-9 [9] Monitoring for the CTR pollutants in effluent shall occur simultaneously with monitoring required for the CTR pollutants in receiving water. [10] The title 22 pollutants are those pollutants for which Maximum Contaminant Levels (MCLs) have been established at title 22, division 4, chapter 15, sections 64431 (inorganic chemicals) and 64444 (organic chemicals) of the California Code of Regulations. Where these pollutants are included in other groups of pollutants (CTR Priority Pollutants), monitoring does not need to be duplicated. Analytical methods shall adhere to the Detection Limits for Purposes of Reporting (DLRs) established by title 22 of the California Code of Regulations, division 4, chapter 15, sections 64432 and 64445.1. [11] Monitoring for the title 22 pollutants in effluent shall occur simultaneously with monitoring required for the title 22 pollutants in receiving water. 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS 5.1. Whole Effluent Acute Toxicity Testing 5.1.1. Routine Acute Toxicity Monitoring Frequency. The Discharger shall conduct at least one acute aquatic toxicity test using the most sensitive species every calendar year during which there is expected to be at least 15 days of discharge in at least one calendar quarter. For the purposes of acute toxicity, the calendar year starts from the initiation of routine monitoring. If the Discharger is unable to sample within the calendar year due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar year was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. 5.1.2. Discharge In-stream Waste Concentration (IWC) for Acute Toxicity. The IWC for this discharge is 100 percent effluent. 5.1.3. Most Sensitive Species. The test species used for acute toxicity testing shall be the most sensitive species. To be consistent with previous Order R3-2014-0033, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct acute toxicity testing from the effective date of this permit until the completion of the required acute species sensitivity screening detailed in section 5.1.6 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation, and the Central Coast Water Board determines that the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-10 Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.1.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.1.5. Acute Freshwater Species and Test Methods. The Discharger shall conduct acute toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136). Approved tests methods for acute toxicity are listed in Table E-4 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-4. Approved Test for Acute Toxicity – Fresh Water Species Effect Test Duration (hours) Test Method Fathead Minnow (Pimephales promelas) Survival 96 Survival Test Method 2000.0 Water Flea (Ceriodaphnia dubia) Survival 48 Survival Test Method 2002.0 5.1.6. Acute Species Sensitivity Screening. The Discharger shall conduct one species sensitivity screening test during the Order’s first required sample collection for acute toxicity. The Discharger shall collect a single effluent sample to initiate and concurrently conduct two toxicity tests using the fish and invertebrate species referenced in Table E-4 above. This sample shall also be analyzed for the parameter(s) required on a mon thly and quarterly frequency in Table E-3, during that given month. Samples for the species sensitivity screening shall be analyzed using the TST approach. The species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-11 than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. 5.1.7. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.1.7.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent Effect” for acute toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.80 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.1.7.2. If the effluent toxicity test does not meet all test acceptability criteria (TAC) specified in the referenced test method, Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136) then the Discharger must resample and re-test within 7 days. 5.1.7.3. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.1.7.4. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.1.8. Notification. The Discharger shall notify the Central Coast Water Board of an exceedance of the acute toxicity trigger of 90 percent survival as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-12 Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.1.9. Accelerated Monitoring Requirements. If the result of any acute toxicity test fails to meet the single test minimum trigger (70 percent survival), and the testing meets all TAC, the Discharger shall take two more samples, one within 14 days and one within 21 days following receipt of the initial sample result. If any one of the additional samples do not comply with the three -sample median minimum limitation (90 percent survival), the Discharger shall initiate a Toxicity Reduction Evaluation (TRE) in accordance with section 5.4 of the MRP. If the two additional samples are in compliance with the acute toxicity requirement and testing meets all TAC, then a TRE will not be required. 5.1.10. Reporting. The Self-Monitoring Report (SMR) shall include a full laboratory report for each toxicity test (WET report). The WET report shall be prepared using the format and content of section 12 (Report Preparation) of Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 5th edition or subsequent editions), including: 5.1.10.1. The toxicity test results in percent (%) survival for the 100 percent effluent sample. 5.1.10.2. The toxicity test results for the TST approach, reported as “Pass” or “Fail” and “Percent Effect” at the acute toxicity IWC for the discharge. 5.1.10.3. Water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.1.10.4. TRE/Toxicity Identification Evaluation (TIE) results. The Executive Officer shall be notified no later than 30 days from completion of each aspect of TRE/TIE analyses. 5.1.10.5. Statistical program (e.g., TST calculator, CETIS, etc.) output results for each toxicity test. 5.2. Chronic Toxicity Monitoring Requirements – Monitoring Location EFF-001 5.2.1. Routine Chronic Toxicity Monitoring Frequency. The Discharger shall conduct at least one chronic aquatic toxicity test every calendar month during which there is expected to be at least 15 days of discharge. Initiation of the routine monitoring test shall be at a time that would allow any required Med ian Monthly Effluent Limitation (MMEL) compliance tests to be initiated within the same calendar month as the routine monitoring test. For routine chronic toxicity monitoring, the Discharger shall conduct at least one chronic toxicity test using the most sensitive species each calendar month during which there is expected to be at least 15 days of discharge. For the purposes of chronic toxicity, the calendar month starts from the initiation of routine monitoring. The Discharger shall ensure there is sufficient time to perform the MMEL compliance testing within the defined calendar month, should the initial toxicity test result in a “Fail”. If the Discharger is unable to sample within the calendar CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-13 month due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar month was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. The Discharger may request to reduce the monitoring frequency from once per calendar month to once per calendar quarter if all of the following conditions are met: 1) the toxicity requirements in this permit have been followed; and 2) there were no violations of the MMEL or Maximum Daily Effluent Limitation (MDEL) for chronic toxicity within the last five years. If a chronic toxicity test results in a “Fail” at the IWC during reduced monitoring, the frequency is automatically increased back to once per month for a period of five years. 5.2.2. Discharge In-stream Waste Concentration (IWC). The IWC for this discharge is 100 percent effluent. 5.2.3. Most Sensitive Species. The test species used for chronic toxicity testing shall be the most sensitive species. To be consistent with Order No. R3 -2014-003, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct chronic toxicity testing from the effective date of this permit until the completion of the required chronic species sensitivity screening described in section 5.2.7 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation and the Central Coast Water Board determines that the Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.2.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.2.5. Chronic Freshwater Species and Test Methods. The Discharger shall conduct chronic toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002; Table IA, 40 C.F.R. part 136). Approved CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-14 tests methods for chronic toxicity are listed in Table E-5 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-5. Approved Tests for Chronic Toxicity – Freshwater Species Effect Test Duration (days) Test Method Fathead Minnow (Pimephales promelas) Larval Survival and Growth 7 Larval Survival and Growth Test Method 1000.0 Water Flea (Ceriodaphnia dubia) Survival and Reproduction 6 to 8 days Survival and Reproduction Test Method 1002.0 Green Alga (Selenastrum capricornutum) Growth 4 days Growth Test Method 1003.0 5.2.6. Median Monthly Effluent Limitation (MMEL) Compliance Monitoring. If a chronic toxicity test conducted during routine monitoring results in a “Fail” at the IWC, the Discharger shall conduct a maximum of two chronic toxicity MMEL compliance tests. The MMEL compliance tests shall be initiated within the same calendar month that the first routine chronic toxicity test was initiated that resulted in a “Fail” at the IWC. If the first chronic toxicity MMEL compliance test results in a “Fail” at the IWC, then the second chronic toxicity MMEL compliance test is not required. 5.2.7. Chronic Species Sensitivity Screening. The Discharger shall conduct four species sensitivity screening tests within 18 months of the effective date of this permit and four species sensitivity screening tests within one year of submitting the ROWD for the Facility, with one set of screenings conducted in each quarter for four consecutive quarters. For each set of species sensitivity screenings, the Discharger shall collect a single effluent sample to initiate and concurrently conduct three toxicity tests using the fish, invertebrate, and alga species referenced in Table E-5 above. This sample shall also be analyzed for the parameter(s) required on a monthly and quarterly frequency in Table E -3, during that given month. As allowed under the test method for the Ceriodaphnia dubia and the Pimephales promelas, a second and third sample shall be collected for use as test solution renewal water as the seven-day toxicity test progresses. Samples for the species sensitivity screening shall be analyzed using the TST approach. After the fourth set of species sensitivity screening, the species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-15 repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. During the calendar month, toxicity tests used to determine the most sensitive test species shall be reported as effluent compliance monitoring results for the MDEL and MMEL for chronic toxicity. 5.2.8. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.2.8.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent (%) Effect” for chronic toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.2.8.2. The MDEL for chronic toxicity is exceeded and a violation will be flagged when a toxicity test during routine monitoring results in “Fail” for the sub -lethal endpoint in accordance with the TST approach and the “Percent Effect” is greater than or equal to 50 percent for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. 5.2.8.3. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. 5.2.8.4. If the effluent toxicity test does not meet all TAC specified in the referenced test method, Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002) then the Discharger must resample and re-test within 14 days. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-16 5.2.8.5. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.2.8.6. Monthly reference toxicant testing is sufficient if in accordance with Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). All reference toxicant test results should be reviewed and reported using the effects concentration at 25 percent (EC25). 5.2.8.7. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.2.9. Notification. The Discharger shall notify the Central Coast Water Board of a violation of a toxicity MDEL or MMEL as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.2.10. Routine Reporting. The SMR shall include a full laboratory report for each chronic toxicity test. This report shall be prepared using the format and content of the test methods manual in section 10 of Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002), Report Preparation, and shall include: 5.2.10.1. The valid toxicity test results for the TST statistical approach, reported as “Pass” or “Fail” and “Percent Effect” at the chronic toxicity IWC for the discharge. All toxicity test results (whether identified as valid or otherwise) conducted during the calendar month shall be reported on the SMR due date specified in Table E-10. 5.2.10.2. Summary water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.2.10.3. The statistical analysis used in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10- 003, 2010) Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. 5.2.10.4. Statistical program (e.g., TST calculator, CETIS, etc.) output results, including graphical plots, for each toxicity test. 5.2.10.5. Tabular data and graphical plots clearly showing the laboratory’s performance for the reference toxicant for the previous 20 tests and the laboratory’s performance for the control mean, control standard deviation, and control coefficient of variation for the previous 12-month period. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-17 5.2.10.6. Any additional quality assurance/quality control (QA/QC) documentation or any additional chronic toxicity-related information, upon written request from the Central Coast Water Board. 5.3. Accelerated Monitoring Requirements 5.3.1. When acute toxicity is detected in the effluent, or when the chronic toxicity effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all TAC, the Discharger shall initiate accelerated monitoring to confirm the effluent toxicity. 5.3.2. The Discharger shall implement an accelerated monitoring frequency consisting of performing three toxicity tests in a six-week period following the first failed test results. 5.3.3. If implementation of the generic Toxicity Reduction Evaluation (TRE) Work Plan indicates the source of the exceedance of the effluent limitation or toxicity trigger (for instance, a temporary plant upset), then only one additional test is necessary. If exceedance of the effluent limitation or toxicity trigger is detected in this test, the Discharger will continue with accelerated monitoring requirements or implement the Toxicity Identification and Toxicity Reduction Evaluations. 5.3.4. If none of the three tests indicated exceedance of the effluent limitation or toxicity trigger, then the Discharger may return to the normal testing frequency. 5.4. Toxicity Identification Evaluations (TIE) and Toxicity Reduction Evaluation (TRE) Process 5.4.1. A TIE shall be triggered if testing from the accelerated monitoring frequency indicates any of the following: 5.4.1.1. Two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. 5.4.1.2. The TIE shall be initiated within 15 days following failure of the second accelerated monitoring test. 5.4.1.3. If a TIE is triggered prior to the completion of the accelerated testing, the accelerated testing schedule may be terminated, or used as necessary in performing the TIE. 5.4.2. The TIE shall be conducted to identify and evaluate toxicity in accordance with procedures recommended by the U.S. EPA, which include the following: 5.4.2.1. Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents, Phase I, (U.S. EPA, 1992a); 5.4.2.2. Methods for Aquatic Toxicity Identification Evaluations: Phase I Toxicity Characterization Procedures, Second Edition (U.S. EPA, 1991a); 5.4.2.3. Methods for Aquatic Toxicity Identification Evaluations: Phase II Toxicity Identification Procedures for Sampling Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993a); and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-18 5.4.2.4. Methods for Aquatic Toxicity Identification Evaluations: Phase III Toxicity Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993b). 5.4.3. As part of the TIE investigation, the Discharger shall be required to implement its TRE Work Plan. The Discharger shall take all reasonable steps to control toxicity once the source of the toxicity is identified. A failure to conduct required toxici ty tests or a TRE within a designated period shall result appropriate enforcement action. Recommended guidance in conducting a TRE includes the following: 5.4.3.1. Toxicity Reduction Evaluation Guidance for Municipal Wastewater Treatment Plants, August 1999, EPA/833B-99/002; and 5.4.3.2. Clarifications Regarding Toxicity Reduction and Identification Evaluations in the National Pollutant Discharge Elimination System Program dated March 27, 2001, U.S. EPA Office of Wastewater Management, Office of Regulatory Enforcement. 5.4.4. The Central Coast Water Board may also require the Discharger conduct a TRE if other information indicates toxicity (e.g., results of additional monitoring, results of monitoring at a higher concentration than the IWC, fish kills, intermittent recurring toxicity), or if there is no effluent available to complete routine monitoring, a MMET test or a MMEL Compliance Test. 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable 7. RECYCLING MONITORING REQUIREMENTS 7.1. Monitoring Location EFF-002 7.1.1. The Discharger shall monitor recycled water at Monitoring Location EFF-002 as described below: Table E-6. Recycled Water Monitoring Requirements at EFF-002 Parameter Units Sample Type Minimum Sampling Frequency[3] Daily Flow MGD Metered Continuous Total Coliform MPN/100 mL Grab 1/Day Turbidity[1] NTU Metered Continuous pH standard units Grab 1/Day Total Chlorine Residual[2] mg/L Metered Continuous [1] Turbidity to be sampled immediately downstream of the membrane bioreactors. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-19 the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] Monitoring is not required during periods recycled water is not being produced for use outside of the Facility. The Discharger shall specify within the SMR if production of recycled water took place during the monitoring period. 7.1.2. In the event the Producer is unable to comply with the conditions of the water recycling requirements and prohibitions, the Producer shall immediately notify the Central Coast Water Board by telephone and submit a written follow-up report with two weeks of the noncompliance. The written report shall include pertinent information explaining reasons for the noncompliance and shall indicate what steps are being taken to prevent the problems from recurring. 7.1.3. An annual self-monitoring report shall be submitted to the Central Coast Water Board by April 1 of the following year. The report shall include the following: 7.1.3.1. A letter transmitting self-monitoring reports shall accompany each report. The letter shall include a discussion of violations found during the reporting period and actions taken or planned for correcting noted violations, such as operation or facility modifications. If the Producer has previously submitted a report describing corrective actions or a time schedule for implementing corrective actions, reference to the previous correspondence will be satisfactory. The transmittal letter shall contain a statement by the Producer or the Producer’s authorized agent, under penalty of perjury, that to the best of the signer’s knowledge the report is true, accurate, and complete. 7.1.3.2. Tabulations of the results of each required analysis by the Producer specified in Table E-6 by date, time, type of sample, and station. 8. RECEIVING WATER MONITORING REQUIREMENTS 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW-008 8.1.1. The Discharger shall monitor the receiving water at Monitoring Locations RSW - 001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW- 008 as follows: Table E-7. Receiving Water Monitoring Requirements Parameter Units Sample Type Sampling Station [1] Minimum Sampling Frequency Flow[2] CFS Instantaneous 4, 5, 7, 8 1/Month Flow MGD Estimated 4, 5, 7, 8 1/Month Turbidity[2] NTU Grab 4, 5, 1/Month Color[2] Color units Grab 4, 5 1/Month CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-20 Parameter Units Sample Type Sampling Station [1] Minimum Sampling Frequency pH[2][4] standard units (s.u.) Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Temperature[4] °C Grab 4, 5 1/Month Un-ionized Ammonia (as N) [4] mg/L Calculated 4, 5 1/Month Nitrate (as N) mg/L Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Total Phosphate (as P) mg/L Grab 5, 7, 8 1/Month Ammonia, Total (as N) [3] mg/L Grab 5, 7, 8 1/Month Total Kjeldahl Nitrogen (as N) mg/L Grab 5, 7, 8 1/Month Total Dissolved Solids (TDS) mg/L Grab 4, 5, 7, 8 1/Month Chloride mg/L Grab 4, 5, 7, 8 1/Month Sulfate mg/L Grab 4, 5, 7, 8 1/Month Sodium mg/L Grab 4, 5, 7, 8 1/Quarter Boron mg/L Grab 4, 5, 7, 8 1/Quarter Hardness, as CaCO3 mg/L Grab 4, 5, 7, 8 1/Quarter Molybdenum mg/L Grab 4, 5, 7, 8 1/Year Methylene Blue Activated Substances mg/L Grab 4, 5, 7, 8 1/Year E. coli MPN/100 mL Grab 4, 5, 7, 8 1/Quarter CTR Pollutants[5], [6] µg/L Grab 4, 5 1/Year Title 22 Pollutants[7], [8] µg/L Grab 4, 5 1/Year [1] Samples shall be obtained only when safe to do so. [2] The San Luis Obispo Creek flow rate shall be used to determine the upstream and downstream stations where these constituents shall be monitored as follows: If the creek flows underground between Monitoring Location RSW-002 and the discharge point, samples shall be obtained from Monitoring Locations RSW-002. If the creek flows aboveground from Monitoring Location RSW-002 to the discharge point, samples shall be obtained from Monitoring Location RSW-004. In either case, Monitoring Location RSW-005 shall be the downstream location. [3] Sampling shall be concurrent with sampling of effluent for ammonia. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-21 [4] Temperature and pH are to be measured at the same time that the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [5] The CTR pollutants are those listed by the CTR at 40 CFR 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). [6] Monitoring of receiving water for the CTR pollutants shall occur simultaneously with effluent monitoring for the CTR pollutants. [7] The title 22 pollutants are those for which primary MCLs have been established and which are listed in sections 64431-A and 64444-A of the California Code of Regulations, title 22, division 4, chapter 15. Where these pollutants are also identified as CTR Priority Pollutants, monitoring does not need to be duplicated. [8] Monitoring of receiving water for the title 22 Pollutants shall occur simultaneously with effluent monitoring for title 22 pollutants. 9. OTHER MONITORING REQUIREMENTS 9.1. Biosolids, Monitoring, and Notification – BIO-001 9.1.1. A representative sample of biosolids shall be obtained from the last point in the handling process (i.e., in the drying beds just prior to removal or from a pond bottom). All constituents shall be analyzed annually for total concentrations for comparison with Total Threshold Limit Concentration (TTLC) criteria. The Waste Extraction Test shall be performed on any constituent when the total concentration of the waste exceeds ten times the Soluble Threshold Limit Concentration (STLC) for that substance. Twelve (12) discrete representative samples shall be collected at separate locations in the biosolids ready for disposal. These 12 samples shall be composited to form one (1) sample for constituent analysis. For accumulated, previously untested biosolids, the Discharger shall develop a representative sampling plan including number and location of sampling points and collect representative samples. The analysis shall test for the metals required in 40 C.F.R. 503.16 (for land application) or 503.26 (for surface disposal), using the methods in Test Methods for Evaluating Solid Waste, Physical/Chemical Methods (U.S. EPA Publication SW-846, all applicable editions and updates), as required in 503.8(b)(4), at the minimum frequencies established therein, provided in the table below. Table E-8. Amount of Biosolids and Frequency of Analysis Amount[1] (dry metric tons/365-day period) Minimum Sampling Frequency[2] Greater than zero, but less than 290 Once per year Equal to or greater than 290 but less than 1,500 Once per quarter (four times per year) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-22 Amount[1] (dry metric tons/365-day period) Minimum Sampling Frequency[2] Equal to or greater than 1,500 but less than 15,000 Once per sixty days (six times per year) Greater than 15,000 Once per month (twelve times per year) [1] For land application, either the amount of bulk biosolids applied to the land or the amount prepared for sale or give-away in a bag or other container for application to the land (dry weight basis). If the Discharger’s biosolids are directly land applied without further treatment by another preparer, biosolids shall also be tested for organic-N, ammonium-N, and nitrate-N at the frequencies required. For surface disposal, the amount of biosolids placed on an active sludge unit (dry weight basis). [2] Test results shall be expressed in mg pollutant per kg biosolids on a 100% dry weight basis. With U.S. EPA approval the amount of biosolids and minimum sampling frequency can coincide with the testing regiment implemented for Cal recycle. Biosolids shall be analyzed for the constituents in the table below. Table E-9. Biosolids Monitoring Requirements Parameter Units Sample Type Minimum Sampling Frequency Quantity Removed Tons or yd3 Measured During Removal Location of Reuse/Disposal General Public or Specific Site -- -- Moisture Content Percent Grab Per Table E-8 (above) pH standard units Grab Per Table E-8 (above) Total Kjeldahl Nitrogen mg/kg[1] Grab Per Table E-8 (above) Ammonia (as N) mg/kg[1] Grab Per Table E-8 (above) Nitrite (as N) mg/kg[1] Grab Per Table E-8 (above) Total Phosphorus mg/kg[1] Grab Per Table E-8 (above) Oil and Grease mg/kg[1] Grab Per Table E-8 (above) Arsenic mg/kg[1] Grab Per Table E-8 (above) Boron mg/kg[1] Grab Per Table E-8 (above) Cadmium mg/kg[1] Grab Per Table E-8 (above) Copper mg/kg[1] Grab Per Table E-8 (above) Chromium (Total) mg/kg[1] Grab Per Table E-8 (above) Lead mg/kg[1] Grab Per Table E-8 (above) Mercury mg/kg[1] Grab Per Table E-8 (above) Molybdenum mg/kg[1] Grab Per Table E-8 (above) Nickel mg/kg[1] Grab Per Table E-8 (above) Selenium mg/kg[1] Grab Per Table E-8 (above) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-23 Parameter Units Sample Type Minimum Sampling Frequency Zinc mg/kg[1] Grab Per Table E-8 (above) [1] Total sample (including solids and any liquid portion) to be analyzed and results reported as mg/kg based on the dry weight of the sample. 9.1.2. Prior to land application, the Discharger shall demonstrate that the biosolids meet Class A or Class B pathogen reduction levels by one of the methods listed in 40 C.F.R. 503.32 (unless transferred to another preparer who demonstrates pathogen reduction). Prior to disposal in a surface disposal site, the Discharger shall demonstrate that the biosolids meet Class B levels or shall ensure that the site is covered at the end of each operating day. If pathogen reduction is demonstrated using a “Process to Significantly/Further Reduce Pathogens “(PFRP), the Discharger shall maintain daily records of the operating parameters to achieve this reduction. The following applies when biosolids from the Discharger are directly land applied as Class B, without further treatment by a second preparer. If the Discharger demonstrates pathogen reduction by direct testing for fecal coliforms and/or pathogens, samples must be drawn at the frequency in the Amount/Frequency table above. If the Discharger demonstrates Class B pathogen reduction by testing for fecal coliform, at least seven grab samples must be drawn and analyzed during each monitoring event, and a geometr ic mean calculated from these seven samples. If the Discharger demonstrates Class A pathogen reduction by testing for fecal coliform and/or salmonella, plus one of the PFRP processes or testing for enteric viruses and helminth ova at least four samples of fecal coliform or salmonella must be drawn during each monitoring event. All four samples must meet the limits specified in 503.32(a). 9.1.3. For biosolids that are land applied or placed in a surface disposal site, the Discharger shall track and keep records of the operational parameters used to achieve Vector Attraction Reduction requirements in 40 C.F.R. 503.33(b). 9.1.4. Class 1 facilities (facilities with pretreatment programs or others designated as Class 1 by the Regional Administrator) and federal facilities with greater than five million gallons per day (MGD) influent flow shall sample biosolids for pollutants listed under CWA section 307(a), as required in the pretreatment section of the permit for Publicly Owned Treatment Works (POTWs) with pretreatment programs. Class 1 facilities and federal facilities greater than 5 MGD shall test dioxins/dibenzofurans using a detection limit of less than one pg/g at the time of their next priority pollutant scan if they have not done so within the past five years, and once per five years thereafter. 9.1.5. The biosolids shall be tested annually, or more frequently if necessary, to determine hazardousness. All constituents regulated under title 22 California Code or Regulations, division 5, chapter 11, article 3 shall be analyzed for comparison with TTLC criteria. The waste extraction test shall be performed on CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-24 any constituent when the total concentration of the waste exceeds ten times the STLC limit for that substance. 9.1.6. If biosolids are placed in a surface disposal site (dedicated land disposal site or monofill), a qualified groundwater scientist shall develop a groundwater monitoring program for the site, or shall certify that the placement of biosolids on the site will not contaminate an aquifer. 9.1.7. Biosolids placed in a municipal landfill shall be tested by the Paint Filter Liquids Test (U.S. EPA Method 9095) at the frequency determined by Table E-9, or more often if necessary, to demonstrate that there are no free liquids. 9.1.8. The Discharger, either directly or through contractual agreements with their biosolids management contractors, shall comply with the following notification requirements: 9.1.8.1. Notification of non-compliance. The Discharger shall notify U.S. EPA Region 9, the State Water Board, and the Regional Water Board located in the region where the biosolids are used or disposed, of any non-compliance within 24 hours if the noncompliance may seriously endanger health or the environment. For other instances of non-compliance, the Discharger shall notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance in writing within five working days of becoming aware of the non -compliance. The Discharger shall require their biosolids management contractors to notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance within the same time frames. 9.1.8.2. If biosolids are shipped to another state or Native American lands, the Discharger must send notice at least 60 days prior to the shipment to the permitting authorities in the receiving state or Native American land (the U.S. EPA Regional Office for that area and the State/Native American authorities). 9.1.8.3. For land application (in cases where Class B biosolids are directly applied without further treatment): Prior to reuse of any biosolids from the Discharger’s facility to a new or previously unreported site, the Discharger shall notify U.S. EPA, the Central Coast Water Board, and any other affected Regional Water Board. The notification shall include description of the crops or vegetation to be grown, proposed loading rates and determination of agronomic rates. If any biosolids within a given monitoring period do not meet 40 C.F.R. 503.13 metals concentrations limits, the Discharger (or its contractor) must pre-notify U.S. EPA, and determine the cumulative metals loading to that site to date, as required in 40 C.F.R. 503.12. The Discharger shall notify the applier of all the applier’s requirements under 40 C.F.R. part 503, including the requirement that the applier certify that the management practices, site restrictions, and any applicable vector attraction reduction requirements have been met. The Discharger shall require the applier to certify at the end of 38 months following application of Class B biosolids that the harvesting restrictions in effect for up to 38 months have been met. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-25 9.1.8.4. For surface disposal: Prior to disposal to a new or previously unreported site, the Discharger shall notify U.S. EPA and the Central Coast Water Board. The notice shall include a description and a topographic map of the proposed site, depth to ground water, whether the site is lined or unlined, site operator, site owner, and any State or local permits. The notice shall describe procedures for ensuring public access and grazing restrictions for three years following site closure. The notice shall include a ground water monitoring plan or description of why ground water monitoring is not required. 9.1.9. The Discharger shall submit an annual biosolids report to the U.S. EPA Region 9 Biosolids Coordinator and Central Coast Water Board by February 19th of each year (per U.S. EPA guidance and 40 C.F.R. part 503) for the period covering the previous calendar year. This report shall include: 9.1.9.1. Annual biosolids removed in dry tons and percent solids. 9.1.9.2. If appropriate, a narrative description of biosolids dewatering and other treatment processes, including process parameters, including a schematic diagram showing biosolids handling facilities. For example, if drying beds are used, report depth of application and drying time. If composting is used, report the temperature achieved and duration. 9.1.9.3. A description of disposal methods, including the following information as applicable related to the disposal methods used at the facility. If more than one method is used, include the percentage and tonnage of annual biosolids production disposed by each method. 9.1.9.3.1. For landfill disposal include: 1) the Regional Water Board waste discharge requirement (WDR) numbers that regulate the landfills used, 2) the present classifications of the landfills used, 3) the results of any ground water monitoring, 4) certifications of management practices, and 5) the names and locations of the facilities receiving biosolids. 9.1.9.3.2. For land application include: 1) the location of the site(s), 2) the Regional Water Board's WDR numbers that regulate the site(s), 3) the application rate in lbs/acre/year (specify wet or dry), 4) certifications of management practices and site restrictions, and 5) subsequent uses of the land. 9.1.9.3.3. For offsite application by a licensed hauler and composter include: 1) the name, address and U.S. EPA license number of the hauler and composter. 9.1.9.4. Copies of analytical data required by other agencies (i.e. U.S. EPA or County Health Department) and licensed disposal facilities (i.e. landfill, land application, or composting facility) for the previous year. 9.1.9.5. Descriptions of pathogen reduction methods and vector attraction reduction methods. Including supporting time and temperature data, and certifications, as required in 40 C.F.R. 503.17 and 503.27. 9.1.9.6. Names mailing address, and street addresses of persons who received biosolids for storage, further treatment, disposal in a municipal waste landfill, or CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-26 for other use or disposal methods not covered above, and amounts delivered to each. 9.1.9.7. For all biosolids used or disposed at the Discharger’s facility, the site and management practice information and certification required in 40 C.F.R. 503.17 and 503.27. 9.1.9.8. For all biosolids temporarily stored, the information required in 40 C.F.R. 503.20 is required to demonstrate temporary storage. 9.1.9.9. Reports shall be submitted in electronically using EPA’s Central Data Exchange website at CDX Home | Central Data Exchange | US EPA (cdx.epa.gov). A PDF copy can be printed and sent to: Executive Officer Central Coast Water Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 9.2. Pretreatment Monitoring By February 1 of each year, the Discharger shall submit an Annual Report to the State Water Board, Central Coast Water Board, and U.S. EPA describing the Discharger’s pretreatment activities over the previous 12 months. In the event that the Discharger is not in compliance with any pretreatment condition of this Order or resulting from pretreatment audits or compliance inspections, then the Discharger shall also include the reasons for noncompliance and state how and when the Discharger will comply with such conditions and requirements. This report shall contain, but not be limited to, the following information: 9.2.1. A summary of analytical results from representative, flow-proportioned, 24-hour composite sampling of the plant's effluent and sludge as provided in the relevant sections of this MRP. The Discharger shall also provide any influent, effluent, or sludge monitoring data for nonpriority pollutants which the Discharger believes may be causing or contributing to interference, pass-through, or adversely impacting sludge quality. Sampling and analysis shall be performed in accordance with the techniques prescribed in 40 C.F.R. part 136 and amendments thereto. 9.2.2. A discussion of upset, interference, or pass-through incidents, if any, at the POTW, which the Discharger knows or suspects were caused by industrial users of the POTW system. The discussion shall include the reasons why incidents occurred, corrective actions taken and, if known, the name and address of the industrial user(s), responsible. Discussions shall also include a review of applicable pollutant limitations to determine whether any additional limitations or changes to existing requirements may be necessary to prevent pass-through, interference, or noncompliance with sludge disposal requirements. 9.2.3. The cumulative number of industrial users that the Discharger has notified regarding Baseline Monitoring Reports and the cumulative number of industrial user responses. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-27 9.2.4. An updated list of the Discharger's industrial users, including their names and addresses, or a list of deletions and additions keyed to a previously submitted list. The Discharger shall provide a brief explanation for each deletion. The list shall identify the industrial users subject to Federal Categorical Standards by specifying which set(s) of standards are applicable. The list shall indicate which categorical industries, or specific pollutants from each industry, are subject to local limitations that are more stringent than the Federal Categorical Standards. The Discharger shall also list the non-categorical industrial users that are subject only to local discharge limitations. The Discharger shall characterize the compliance status of each industrial user by employing the following descriptions. 9.2.4.1. In compliance with Baseline Monitoring Report requirements (where applicable); 9.2.4.2. Consistently achieving compliance; 9.2.4.3. Inconsistently achieving compliance; 9.2.4.4. Significantly violated applicable pretreatment requirements defined by 40 C.F.R. 403.8 (f)(2)(vii); 9.2.4.5. On a schedule to achieve compliance (include the date final compliance is required); 9.2.4.6. Not achieving compliance and not on a compliance schedule; or 9.2.4.7. The Discharger does not know the industrial user's compliance status. A report describing the compliance status of any industrial user characterized by descriptions in Items 9.2.4.4.3. through 9.2.4.4.7., above, shall be submitted quarterly from the annual report date to the State Water Board, Central Coast Water Board, and U.S. EPA. The report shall identify the specific compliance status of each such industrial user. This quarterly reporting requirement shall commence upon issuance of this Order. Quarterly reports shall be submitted May 1, August 1, and November 1. The fourth quarter report shall be incorporated in the Annual Report (February 1). Quarterly reports shall briefly describe POTW compliance with audit/pretreatment compliance inspection requirements. If none of the aforementioned conditions exist, at a minimum, a letter indicating that all industries are in compliance and no violations or changes to the pretreatment program have occurred during the quarter must be submitted. 9.2.4.8. A summary of inspection and sampling activities conducted by the Discharger during the past year to gather information and data regarding industrial users. The summary shall include the following: 9.2.4.8.1. Names and addresses of the industrial users subject to surveillance by the Discharger and an explanation of whether they were inspected, sampled, or both and the frequency of these activities at each user; and 9.2.4.8.2. Conclusions or results from the inspection or sampling of each industrial user. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-28 9.2.4.9. A summary of compliance and enforcement activities during the past year. The summary shall include names and addresses of the industrial users affected by the following actions. 9.2.4.9.1. Warning letters or notices of violation regarding the industrial users' apparent noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the apparent violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.2. Administrative Orders regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.3. Civil actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.4. Criminal actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned Federal Categorical Standards or local discharge limitations; 9.2.4.9.5. Assessment of monetary penalties. For each industrial user, identify the amount of the penalties; 9.2.4.9.6. Restriction of flow to the POTW; and 9.2.4.9.7. Disconnection from discharge to the POTW. 9.2.4.10. Description of any significant changes in operating the pretreatment program, which differ from the information in the Discharger's approved POTW Pretreatment Program including, but not limited to, changes concerning: 9.2.4.10.1. The program's administrative structure; 9.2.4.10.2. Local industrial discharge limitations; 9.2.4.10.3. Monitoring program and monitoring frequencies; 9.2.4.10.4. Legal authority or enforcement policy; 9.2.4.10.5. Funding mechanisms; 9.2.4.10.6. Resource requirements; and 9.2.4.10.7. Staffing levels. 9.2.4.11. A summary of the annual pretreatment budget, including costs of pretreatment program functions and equipment purchases. 9.2.4.12. A summary of public participation activities to involve and inform the public. 9.2.4.13. A description of any changes in sludge disposal methods and a discussion of any concerns not described elsewhere in the report. The pretreatment quarterly and annual reports shall be signed by a principal executive officer, CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-29 ranking elected official, or other duly authorized employee who is responsible for the overall operation of the Discharger (POTW - 40 C.F.R. section 403.12(m)). The Discharger shall submit signed copies of the reports to the State Water Board and the Regional Water Board electronically through the SMR module of CIWQS. Signed copies of the reports shall also be submitted electronically to U.S. EPA at R9Pretreatment@epa.gov or as instructed otherwise. 9.3. Salt and Nutrient Management Plan Reporting The previous Order required the Discharger to develop and implement an ongoing salts management plan dedicated to minimize the discharge of salts to and attainment of applicable water quality objectives (WQOs) for salts in San Luis Obispo Creek sub- basin of the Estero Bay Drainage Basin. Additionally, the previous order required the Discharger to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable WQOs for nutrients in the same basin. Based on the annual reports supplied by the Discharger, over the previous period of the Order, the Discharger has demonstrated that the effluent has contributed to exceedances of 2019 Basin Plan WQOs for salts. By February 1 of each year, the Discharger shall submit an annual report (separate from the NPDES annual report) describing salt and nutrient reduction efforts. The report shall include, at a minimum: 9.3.1. Salt Component 9.3.1.1. Calculations of annual salt mass discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; 9.3.1.2. Analysis of wastewater evaporation/salt concentration effects; 9.3.1.3. Analysis of groundwater monitoring results for salts constituents and associated trends; 9.3.1.4. Analysis of potential impacts of salt loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.1.5. A summary of existing salt reduction measures; and, 9.3.1.6. Recommendations and time schedules for implementation of any additional salt reduction measures. 9.3.2. Nutrient Component 9.3.2.1. Calculations of annual nitrogen mass (for all identified species) discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; 9.3.2.2. Analysis of wastewater treatment facility ability to facilitate nitrification and denitrification, or other means of nitrogen removal; 9.3.2.3. Analysis of groundwater monitoring results for nitrogen constituents and trends; CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-30 9.3.2.4. Analysis of potential impacts of nitrogen loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.2.5. A summary of existing nitrogen loading reduction measures; and, 9.3.2.6. Recommendations and time schedules for implementation of any additional nitrogen loading reduction measures. 9.4. Volumetric Monitoring of Wastewater and Recycled Water 9.4.1. Monthly volume of wastewater collected and treated by the wastewater treatment plant. 9.4.2. Monthly volume of wastewater treated, specifying level of treatment, including treated wastewater discharged. 9.4.3. Monthly volume of treated wastewater discharged, monthly volume of recycled water distributed for reuse, and annual volume of treated wastewater distributed for beneficial use in compliance with California Code of Regulations, title 22 use categories. 9.5 Discharge to Evaporation Ponds 9.5.1. The Discharger shall provide written notification to the Central Coast Water Board when there is any discharge to or from the Facility’s evaporation ponds, which are described in section 2.1 of the Fact Sheet. If the discharge is anticipated, the Discharger shall provide notice within 10 days prior to the anticipated discharge. If the discharge is unanticipated, the Discharger sh all provide notice within 24 hours of the time the discharge occurs. Discharge from the evaporation ponds is not permitted in this Order, so standard provision 5.5 applies. The notification must include discharge dates, times, volumes, and reasons for discharge. The notification must be submitted electronically, consistent with standard provision 5.10. 10. REPORTING REQUIREMENTS 10.1. General Monitoring and Reporting Requirements The Discharger shall comply with all Standard Provisions (Attachment D) related to monitoring, reporting, and recordkeeping. 10.2. Self-Monitoring Reports (SMRs) 10.2.1. The Discharger shall electronically submit SMRs using the State Water Board’s California Integrated Water Quality System (CIWQS) Program website (http://www.waterboards.ca.gov/water_issues/programs/ciwqs). The CIWQS website will provide additional information for SMR submittal in the event there will be a planned service interruption for electronic submittal. 10.2.2. The Discharger shall report in the SMR the results for all monitoring specified in this MRP under sections 3 through 9. The Discharger shall submit SMRs including the results of all required monitoring using U.S. EPA -approved test CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-31 methods or other test methods specified in this Order. SMRs are to include all new monitoring results obtained since the last SMR was submitted. If the Discharger monitors any pollutant more frequently than required by this Order, the results of this monitoring shall be included in the calculations and reporting of the data submitted in the SMR. 10.2.3. Monitoring periods and reporting for all required monitoring shall be completed according to the following schedule: Table E-10. Monitoring Periods and Reporting Schedule SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date NPDES Monitoring Report – Continuous, Daily, Weekly, Monthly MRP Sections 3 (Influent), 4 (Effluent) and 5 (Whole Effluent Toxicity), 9.5 Monthly First day of second calendar month following period of sampling Updated Toxicity Reduction Evaluation Work Plan Permit Section 6.3.2.1.1 Once 90 days following permit NPDES Monitoring Report - Quarterly MRP Sections 4 (Effluent) and 8.1 (Receiving Water) Quarterly May 1st August 1st November 1st February 1st NPDES Monitoring Report – Annually MRP Sections 4 (Effluent) and 8.1 (Receiving Water), 9.5 Annually February 15th Recycled Water Monitoring Report MRP Section 7.1 (Recycled Water Monitoring) Annually April 1st, the year following Recycled Water Volumetric Monitoring MRP Section 9.4 (Volumetric Reporting of Wastewater and Recycled Water) Annually April 30th, the year following sampling Note: This report is submitted using CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-32 SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date the GeoTracker system, not CIWQS Biosolids Monitoring Report MRP Section 9.1 (Biosolids Monitoring) Annually February 19th, the year following sampling Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Quarterly May 1st August 1st November 1st February 1st Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Annually February 15th, the year following sampling Summary Report Attachment D, Standard Provision, 8.4.8 (page D-16) Annually February 15th, the year following Salt and Nutrient Management Plan Annual Report MRP Section 9.3 (Salt and Nutrient Management Plan Reporting) Annually February 15th, the following year Pollutant Minimization Program Annual Report Permit Section 6.3.3.2 (Pollutant Minimization Program) Annually February 15th, the following year Climate Change Implementation Progress Report Permit Section 6.3.6.2 (Climate Change Adaptation Implementation Progress Report) Every five years May 1st, every five years following permit effective date. ROWD Application Permit renewal application Once per permit term 180 days prior to permit expiration date 10.2.4. Reporting Protocols. The Discharger shall report with each sample result the applicable Reporting Level (RL) and the current Method Detection Limit (MDL), as determined by the procedure in 40 C.F.R. part 136. The Discharger shall report the results of analytical determinations for the presence of chemical constituents in a sample using the following reporting protocols: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-33 10.2.4.1. Sample results greater than or equal to the RL shall be reported as measured by the laboratory (i.e., the measured chemical concentration in the sample). 10.2.4.2. Sample results less than the RL, but greater than or equal to the laboratory’s MDL, shall be reported as “Detected, but Not Quantified,” or DNQ. The estimated chemical concentration of the sample shall also be reported. For the purposes of data collection, the laboratory shall write the estimated chemical concentration next to DNQ. The laboratory may, if such information is available, include numerical estimates of the data quality for the reported result. Numerical estimates of data quality may be percent accuracy (± a percentage of the reported value), numerical ranges (low to high), or any other means considered appropriate by the laboratory. 10.2.4.3. Sample results less than the laboratory’s MDL shall be reported as “Not Detected,” or ND. 10.2.4.4. Dischargers are to instruct laboratories to establish calibration standards so that the ML value (or its equivalent if there is differential treatment of samples relative to calibration standards) is the lowest calibration standard. At no time is the Discharger to use analytical data derived from extrapolation beyond the lowest point of the calibration curve. 10.2.5. Compliance Determination. Compliance with effluent limitations for priority pollutants shall be determined using sample reporting protocols defined above and Attachment A. For purposes of reporting and administrative enforcement by the Central Coast Water Board and State Water Board, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the priority pollutant in the monitoring sample is greater than the effluent limitation and greater than or equal to the reporting level (RL). 10.2.6. Multiple Sample Data. When determining compliance with an AMEL, AWEL, or MDEL for priority pollutants and more than one sample result is available, the Discharger shall compute the arithmetic mean unless the data set contains one or more reported determinations of “Detected, but Not Quantified” (DNQ) or “Not Detected” (ND). In those cases, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 10.2.6.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 10.2.6.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 10.2.7. The Discharger shall submit SMRs in accordance with the following requirements: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-34 10.2.7.1. The Discharger shall arrange all reported data in a tabular format. The data shall be summarized to clearly illustrate whether the facility is operating in compliance with interim and/or final effluent limitations. The Discharger is not required to duplicate the submittal of data that is entered in a tabular format within CIWQS. When electronic submittal of data is required and CIWQS does not provide for entry into a tabular format within the system, the Discharger shall electronically submit the data in a tabular format as an attachment. 10.2.7.2. The Discharger shall attach a cover letter to the SMR. The information contained in the cover letter shall clearly identify violations of the waste discharge requirements; discuss corrective actions taken or planned; and the proposed time schedule for corrective actions. Identified violations must include a description of the requirement that was violated and a description of the violation. 10.2.7.3. The Discharger shall electronically self-report all violations of the waste- discharge requirements using the CIWQS self-reported violations function. 10.3. Discharge Monitoring Reports (DMRs) 10.3.1. DMRs are U.S. EPA reporting requirements. The Discharger shall electronically certify and submit DMRs together with SMRs using Electronic Self-Monitoring Reports module eSMR 2.5 or any upgraded version. Electronic DMR submittal shall be in addition to electronic SMR submittal. Information about electronic DMR submittal is available at the DMR website at: (http://www.waterboards.ca.gov/water_issues/programs/discharge_monitoring). 10.4. Other Reports 10.4.1. The Discharger shall report the results of any special studies, acute and chronic toxicity testing, TRE/TIE, and PMP, required by Special Provisions – 6.3. The Discharger shall report the progress in satisfaction of compliance schedule dates specified in Special Provisions – 6.3.7. The Discharger shall submit reports with the first monthly SMR scheduled to be submitted on or immediately following the report due date. 10.4.2. The Discharger shall report the volumetric monitoring requirements as specified in Other Monitoring Requirements - 9.4 to the State Water Board by April 30 of each calendar year. The Discharger shall electronically certify and submit this annual report containing the required data via the State Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. Information about the volumetric reporting of wastewater and recycled water and the Recycled Water Policy is available at the Recycled Water Policy Volumetric Annual Reporting website at http://www.waterboards.ca.gov/recycledwaterpolicy. 10.4.3. Every five years, the Discharger shall submit a Climate Change Implementation Progress Report as specified in section 6.3.6.2 of this Order. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-1 F. ATTACHMENT F – FACT SHEET TABLE OF CONTENTS 1. PERMIT INFORMATION .......................................................................................... F-3 2. FACILITY DESCRIPTION ........................................................................................ F-5 2.1. Description of Wastewater and Biosolids Treatment and Controls ........................ F-5 2.2. Discharge Points and Receiving Waters ............................................................... F-6 2.3. Summary of Existing Requirements and Self Monitoring Report Data .................. F-6 2.4. Summary of Interim Effluent Limits and Time Schedule Orders ............................ F-8 2.5. Compliance Summary ........................................................................................... F-9 2.6. Planned Changes ................................................................................................ F-10 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS ...................................... F-10 3.1. Legal Authorities.................................................................................................. F-11 3.2. California Environmental Quality Act (CEQA) ..................................................... F-11 3.3. State and Federal Laws, Regulations, Policies, and Plans ................................. F-11 3.4. Impaired Waterbodies on the CWA section 303(d) List ....................................... F-15 3.5. Other Plans, Polices and Regulations ................................................................. F-15 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS ................................................................................................................................... F-17 4.1. Discharge Prohibitions ........................................................................................ F-17 4.2. Technology-Based Effluent Limitations ............................................................... F-18 4.3. Water Quality-Based Effluent Limitations (WQBELs) .......................................... F-20 4.4. Final Effluent Limitation Considerations .............................................................. F-42 4.5. Interim Effluent Limitations – Not Applicable ....................................................... F-47 4.6. Land Discharge Specifications – Not Applicable ................................................. F-47 4.7. Recycling Specifications ...................................................................................... F-47 4.8. Point of Compliance for Effluent Limitations ........................................................ F-47 5. RATIONALE FOR RECEIVING WATER LIMITATIONS ........................................ F-48 5.1. Surface Water ..................................................................................................... F-48 6. RATIONALE FOR PROVISIONS ........................................................................... F-48 6.1. Standard Provisions ............................................................................................ F-48 6.2. Special Provisions ............................................................................................... F-48 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS .............. F-52 7.1. Influent Monitoring ............................................................................................... F-53 7.2. Effluent Monitoring .............................................................................................. F-53 7.3. Whole Effluent Toxicity Testing Requirements .................................................... F-53 7.4. Recycled Water Monitoring ................................................................................. F-54 7.5. Receiving Water Monitoring ................................................................................ F-54 7.6. Other Monitoring Requirements .......................................................................... F-55 9. PUBLIC PARTICIPATION ...................................................................................... F-58 9.1. Notification of Interested Persons........................................................................ F-58 9.2. Written Comments ............................................................................................... F-59 9.4. Reconsideration of Waste Discharge Requirements ........................................... F-59 9.5. Information and Copying ..................................................................................... F-59 9.6. Register of Interested Persons ............................................................................ F-60 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-2 9.7. Additional Information .......................................................................................... F-60 TABLE OF TABLES Table F-1. Facility Information ...................................................................................... F-3 Table F-2. Historic Effluent Limitations and Monitoring Data ........................................ F-7 Table F-3. TSO R3-2014-0036 Interim Effluent Limits ................................................. F-9 Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 ...... F-9 Table F-5. Basin Plan Beneficial Uses ....................................................................... F-12 Table F-6. Secondary Treatment Requirements ........................................................ F-19 Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 ................. F-19 Table F-8. Summary of RPA Results ......................................................................... F-23 Table F-9. Summary of Acute and Chronic Toxicity Test Results .............................. F-39 Table F-10. Final Effluent Limitations – Discharge Point EFF-001 ............................. F-44 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-3 ATTACHMENT F – FACT SHEET As described in section 2.2 of this Order, the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) incorporates this Fact Sheet as findings of the Central Coast Water Board supporting the issuance of this Order. This Fact Sheet includes the legal requirements and technical rationale that serve as the basis for the requirements of this Order. This Order has been prepared under a standardized format to accommodate a broad range of discharge requirements for dischargers in California. Only those sections or subsections of this Order that are specifically identified as “not applicable” have been determined not to apply to this Discharger. Sections or subsections of this Order not specifically identified as “not applicable” are applicable to this Discharger. 1. PERMIT INFORMATION The following table summarizes administrative information related to the facility. Table F-1. Facility Information WDID 3 400107001 Discharger City of San Luis Obispo Name of Facility City of San Luis Obispo Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Facility Contact, Title and Phone Patrick McGrath, WRRF Supervisor 805-781-7240 Authorized Person to Sign and Submit Reports Patrick McGrath, WRRF Supervisor 805-781-7240 Mailing Address 35 Prado Road, San Luis Obispo, CA 93401 Billing Address 35 Prado Road, San Luis Obispo, CA 93401 Type of Facility Publicly Owned Treatment Works (POTW) Major or Minor Facility Major Threat to Water Quality 2 Complexity A Pretreatment Program Yes CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-4 Recycling Requirements Production: NPDES R3-2024-0001 Distribution and Use: WQ 2016-0068, DDW Water Reclamation Requirements for Recycled Water Facility Permitted Flow 5.4 million gallons per day (MGD) Facility Design Flow 5.4 MGD Watershed Estero Bay Hydrologic Unit Receiving Water San Luis Obispo Creek Receiving Water Type Inland surface water 1.1. The City of San Luis Obispo (hereinafter Discharger or the City) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (hereinafter Facility), a publicly owned treatment works (POTW). For the purposes of this Order, references to the “discharger” or “permittee” in applicable federal and state laws, regulations, plans, or policy are held to be equivalent to references to the Discharger herein. 1.2. The Facility discharges wastewater to San Luis Obispo Creek, a water of the United States. 1.3. When applicable, state law requires dischargers to file a petition with the State Water Resources Control Board (State Water Board), Division of Water Rights and receive approval for any change in the point of discharge, place of use, or purpose of use of treated wastewater that decreases the flow in any portion of a watercourse. The State Water Board retains separate jurisdictional a uthority to enforce any applicable requirements under California Water Code section 1211. This is not an NPDES permit requirement. 1.4. The Discharger was previously regulated by Order R3-2014-0033 and National Pollutant Discharge Elimination System (NPDES) Permit CA0049224 adopted on September 25, 2014, and effective on December 1, 2014. The Discharger was also regulated by Time Schedule Order R3-2014-0036 and Time Schedule Order R3- 2019-0124. The Discharger filed a Report of Waste Discharge (ROWD) and submitted an application for reissuance of its waste discharge requirements (WDRs) and NPDES permit on May 28, 2019. 1.5. The Discharger was previously regulated by Waste Discharge Requirements and Master Reclamation Requirements Order R3-2003-081, which authorized the production, distribution, and use of recycled water. 1.6. Federal regulations at 40 C.F.R. section 122.46 limit the duration of NPDES permits to a fixed term not to exceed five years. However, pursuant to California Code of Regulations, title 23, section 2235.4, the terms and conditions of an expired permit are automatically continued pending reissuance of the permit if the Discharger complies with all federal NPDES requirements for continuation of expired permits. Because the Discharger met the requirements of California Code of Regulations, title 23, section 2235.4, Order No. R3-2014-0033, NPDES Permit No. CA0049224 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-5 was administratively continued after the original expiration date of November 30, 2019. 2. FACILITY DESCRIPTION 2.1. Description of Wastewater and Biosolids Treatment and Controls The City of San Luis Obispo Resource Recovery Facility is a municipal wastewater collection, treatment, and disposal facility that discharges tertiary treated wastewater to San Luis Obispo Creek. First constructed in 1920 and located at the southwest corner of the City of San Luis Obispo and adjacent to San Luis Obispo Creek, the Facility provides sewerage service to approximately 47,328 municipal and industrial users from the City of San Luis Obispo, California Polytechnic State University, San Luis Obispo, and the San Luis Obispo County Regional Airport. The City also administers an approved pretreatment program that includes seven significant industrial users, as defined in federal regulations. The Discharger currently operates a collection system that is composed of over 148 miles of main line and 9 lift stations. The design flow capacity of the Facility is 5.4 MGD. During storm events, the estimated wet weather influent flow to the facility is 11.1 MGD due to inflow and infiltration into the collection system from aging or broken/cracked pipes. Ongoing capital improvement projects for sewer line replacement, flow metering, and main line repairs will continue to address areas of concern that result in inflow and infiltration into the Facility. The Discharger has been implementing a significant upgrade of the Facility’s biological, disinfection, and biosolids units since 2019. A focus of the facility upgrade was to improve removal of chorine disinfection byproducts (trihalomethanes, or THMs) and nitrate to meet effluent limits of the previous permit. Another focus of the upgrade was to increase the facility’s ability to treat high inflows from wet-weather events. Prior to the most recent upgrades, the facility’s treatment process consisted of an equalization basin, mechanical screening, grit removal, primary settling, biofiltration, secondary settling, nitrification with two activated sludge aeration basins, final settling, cooling using evaporative cooling towers, dual media filtration, and chlorination/dechlorination. During the upgrade, the discharger removed or abandoned the following components of the facility: bio filter and secondary clarifier, final clarifiers, tertiary dual media filtration, and chlorine disinfection and dechlorination. The two activated sludge basins were converted to Modified Ludzack-Ettinger (MLE) bioreactors for nutrient removal, the dissolved air floatation thickener (DAFT) was modified into a sludge blend tank, and a digester was modified into an odor control unit. The final upgraded treatment system currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four MLE bioreactors, hollowfiber membranes, and UV disinfection. Although chlorination and dechlorination of the effluent and recycled water has been terminated due to the use of UV disinfection, the recycled water sent to the storage tank will be dosed with chlorine to maintain a chlorine residual in the recycled water distribution line per best practices of the distribution system. The Discharger may use sodium hypochlorite (chlorine) for CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-6 maintenance purposes such as membrane cleaning in the MLE unit when hydrogen peroxide and/or citric acid is insufficient. If chlorine is used for membrane cleaning, dechlorination of the effluent with sodium bisulfite may be necessary remove the chlorine residual to protect beneficial uses of San Luis Obispo Creek. Biosolids were previously handled with a dissolved air floatation thickener (DAFT), three anaerobic digesters, a screw press, a belt filter press, and drying beds, with the final product shipped out for composting. The upgraded biosolids handling train now consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, a digested sludge storage tank, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. There are two lined evaporation ponds located at southwest corner of the Facility property. The Discharger has occasionally diverted wastewater to these ponds when it did not meet effluent limitations, rather than discharging the wastewater to the creek. This Order requires the Discharger to submit a written notification to the Central Coast Water Board when wastewater is sent to these ponds. This Order does not provide regulatory coverage for the discharge of wastewater from these ponds to land or surface water. In recent years with large, prolonged storm events, these ponds have filled with stormwater from overland flow (not from the facility). This Order does not provide coverage of stormwater discharge from these ponds. As discussed further in section 3.5.1 of this Fact Sheet, the Discharger is enrolled in the Industrial General Permit (State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001). The Discharger may incorporate these ponds into their Industrial General Permit enrollment to allow for the discharge of stormwater from the ponds, in compliance with all the requirements of the Industrial General Permit. 2.2. Discharge Points and Receiving Waters Tertiary treated wastewater is discharged from Discharge Point EFF-001 to San Luis Obispo Creek, a water of the United States, at latitude 35.244307° N and longitude 120.680618° W. Sampling location EFF-001A is located prior to discharge into the effluent pipeline that discharges to San Luis Obispo Creek. Sampling location EFF-001B is located at the most downstream end of the effluent pipeline that discharges to San Luis Obispo creek. The flowrate in San Luis Obispo Creek varies greatly between the wet and dry seasons. No dilution credit has been granted for this discharge. Tertiary treated wastewater is discharged from Discharge Point EFF-002 to the Discharger’s reclaimed water storage tank that is located just south of the UV disinfection system. The reclaimed water storage tank feeds the Discharger’s reclaimed water distribution lines located throughout the city. 2.3. Summary of Existing Requirements and Self Monitoring Report Data Effluent limitations contained in Order R3-2014-0033 for discharges from Discharge Point 001 (Monitoring Location EFF-001) and representative monitoring data from December 1, 2014, to December 1, 2022, are shown in Table F-2: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-7 Table F-2. Historic Effluent Limitations and Monitoring Data Parameter Units Averag e Monthl y Effluen t Limit Averag e Weekly Effluen t Limit Maximum Daily Effluent Limit Highest Average Monthly Discharge Reported Highest Average Weekly Discharge Reported Highest Daily Discharge Reported Flow (dry weather) MGD 5.1 --- --- 8.0 --- 12.9[1] Biochemical Oxygen Demand 5- day @ 20°C (BOD5) milligra ms per liter (mg/L) 10 30 50 8.84 14.3 12.6 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) pounds per day (lbs/day ) 425 1275 2125 382 382 382 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) percent removal ≥85 --- --- 91.6 – 100[2] Total Suspended Solids (TSS) mg/L 10 30 75 7.9 11 23.3 Total Suspended Solids (TSS) lbs/day 425 1275 3190 572 842 1556 Total Suspended Solids (TSS) percent removal ≥85 --- --- 97.3-99.7[2] --- --- Oil and Grease mg/L 5 --- 10 8 --- 8 Settleable Solids milliliter per liter per hour (mL/L/h r) 0.1 --- --- <0.1 --- --- pH standar d units 6.5– 8.3[3] 6.5 – 7.88[4] Nitrate, Total (as N) mg/L 10 --- --- 51.7 --- --- Chlorodibro momethane µg/L 0.4 --- 1.0 5 --- 5 Dichlorobro momethane µg/L 0.56 --- 1.0 22 --- 22 N- Nitrosodimet hylamine µg/L 0.0006 9 --- 0.0014 ND --- ND Dissolved Oxygen mg/L 4.0[5] 4.8 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-8 Chlorine Residual mg/L --- --- ND[6] --- --- 0.76 Chronic Toxicity Toxic Units Chronic (TUc) --- --- 1.0 --- --- 4.0 Fecal or Total Coliform Bacteria Most probabl e number (MPN)/ 100 mL [7] [8] [9] 79, 94[10] 1.8 350 [1] Reported as maximum daily. Flow occurred in February 2017 during a wet weather event. [2] The numbers represent the range of lowest to highest reported values. [3] Applied as an instantaneous minimum and maximum effluent limitation. [4] Representative values contain the lowest instantaneous minimum to the highest instantaneous maximum. [5] Applied as an instantaneous minimum effluent limitation. [6] ND = less than 0.1 mg/L. Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [7] No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 -day period. [8] The median number of fecal coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days for which analyses have been completed. [9] The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [10] Values occurred within a 30-day time period. 2.4. Summary of Interim Effluent Limits and Time Schedule Orders During the permit term for Order R3-2014-0036, the discharger could not immediately achieve compliance with the chlorodibromomethane, dichlorobromomethane, and nitrate effluent limitations. The Central Coast Water Board issued two time schedule orders (TSOs) to set interim effluent limits and compliance timelines: TSO R3-2014- 0036 and TSO R3-2019-0124. TSO R3-2014-0036 set interim limits for the three aforementioned effluent limits with full compliance with effluent limits by November 30, 2019. With the planned upgrades to the Facility’s biological and disinfection units, TSO R3-2019-0124 extended the deadlines to meet the interim effluent limits with a compliance deadline of March 31, 2020, for chlorodibromomethane and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-9 dichlorobromomethane and a compliance deadline of July 31, 2023 for nitrate. Table F- 3 summarizes the interim effluent limits that were established. The interim effluent limitations were established based on the Facility’s performance. When operating under a TSO, if effluent concentrations exceed the final effluent limitation but do not exceed the interim effluent limitation, an effluent violation has not occurred, and mandatory minimum penalties do not apply. If effluent concentrations exceed both the final and interim effluent limitation values, then an effluent violation has occurred, and mandatory minimum penalties do apply. Table F-3. TSO R3-2014-0036 Interim Effluent Limits Constituent Units Average Monthly Maximum Daily Chlorodibromomethane µg/L - 42 Dichlorobromomethane µg/L - 36 Nitrate (as Nitrogen) mg/L 42.6 - 2.5. Compliance Summary 2.5.1 Effluent Compliance Summary The following discussion is a summary of the violations that occurred during the term and administrative extension of Order No. R3-2014-0033. During the time period from December 1, 2014, to May 31, 2023, the Discharger incurred effluent violations related to nitrate, oil and grease, total coliform, chlorine residual, dichlorobromomethane, and chlorodibromomethane. The number of violations, violation type, and reported value range are provided in Table F-4. Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Nitrate (Total as N) December 2016- November 2022 Monthly Average (Mean) Limit 9 43.2-51.7 10 mg/L Oil and Grease March 2017 Monthly Average Limit 1 6 5 mg/L CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-10 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Total Coliform July 2018- October 2020 30-Day Specific Limit 3 33-1600 23 MPN/ 100m L Total Coliform December 2019- October 2020 Daily Maximum 3 540-1600 240 MPN/ 100m L Residual Chlorine February 2020- December 2022 Daily Maximum 2 0.35-0.75 ND mg/L Dichlorobro momethane April 2020- October 2022 Monthly Average Limit 4 2.5-17.8 0.56 µg/L Dichlorobro momethane April 2020- October 2022 Daily Maximum 4 2.5-17.8 1 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Monthly Average Limit 3 1.2-5 0.40 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Daily Maximum 3 1.2-5 1 µg/L 2.6. Planned Changes The Discharger will continue to implement planned upgrades through 2024. The Discharger has not indicated it plans any significant changes to the Facility beyond those during the term of the Order. 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS The requirements contained in this Order are based on the requirements and authorities described in this section. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-11 3.1. Legal Authorities This Order serves as WDRs pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA), implementing regulations promulgated by the U.S. Environmental Protection Agency (U.S. EPA), and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as an NPDES permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1, subject to the WDRs in this Order. 3.2. California Environmental Quality Act (CEQA) Under California Water Code section 13389, this action to adopt an NPDES permit for an existing facility is exempt from the California Environmental Quality Act (CEQA) provisions in Public Resources Code, division 13, chapter 3 (commencing with section 21100). With respect to the recycling specifications and groundwater limitations, this action is exempt from the provisions of CEQA pursuant to title 14, California Code of Regulations, section 15301, class 1 exemption for permitting of existing facilities with no expansion of existing use. 3.3. State and Federal Laws, Regulations, Policies, and Plans 3.3.1. Water Quality Control Plan. The Central Coast Water Board adopted the Water Quality Control Plan for the Central Coastal Basin (Basin Plan), which designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for all waters addressed through the plan. Requirements in this Order implement the Basin Plan. In addition, the Basin Plan implements State Water Board Resolution 88 -63, which established state policy that all waters, with certain exceptions, should be considered suitable or potentially suitable for municipal or domestic supply. Beneficial uses established by the 2019 Basin Plan for San Luis Obispo Creek (below W. Marsh Street) are presented below: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-12 Table F-5. Basin Plan Beneficial Uses Discharge Point Receiving Water Name Beneficial Use(s) 001 San Luis Obispo Creek (below W. Marsh Street) Existing: Municipal and Domestic Supply (MUN); Agricultural Supply (AGR); Ground Water Recharge (GWR); Water Contact Recreation (REC-1); Non-Contact Water Recreation (REC-2); Wildlife Habitat (WILD); Cold Freshwater Habitat (COLD); Warm Freshwater Habitat (WARM); Migration of Aquatic Organisms (MIGR) Spawning, Reproduction, and/or Early Development (SPWN); Fresh Water Replenishment (FRSH) Commercial and Sport Fishing (COMM). Intermittent: None. Potential: None. Groundwater throughout the Central Coast Region has designated beneficial uses of agricultural water supply, municipal and domestic water supply, and industrial use. Requirements of this Order implement the Basin Plan. 3.3.2. Thermal Plan. The State Water Board adopted the Water Quality Control Plan for Control of Temperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of California (Thermal Plan) January 7, 1971, and amended the plan on September 18, 1975. This plan contains temperature objectives for surface waters. Requirements of this Order implement the Thermal Plan. 3.3.3. Sediment Quality. The State Water Board adopted the Water Quality Control Plan for Enclosed Bays and Estuaries – Part 1, Sediment Quality on September 16, 2008, and it became effective on August 25, 2009. This plan supersedes other narrative sediment quality objectives and establishes new sediment quality objectives and related implementation provisions for specifically defined sediments in most bays and estuaries. Requirements of this Order implement sediment quality objectives of this plan. 3.3.4. National Toxics Rule (NTR) and California Toxics Rule (CTR). U.S. EPA adopted the NTR on December 22, 1992, and later amended it on May 4, 1995 , and November 9, 1999. About forty criteria in the NTR apply in California. On May 18, 2000, U.S. EPA adopted the CTR. The CTR promulgated new toxics criteria for California and, in addition, incorporated the previously adopted NTR criteria CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-13 that were applicable in the state. The CTR was amended on February 13, 2001. These rules contain federal water quality criteria for priority pollutants. 3.3.5. State Implementation Policy. On March 2, 2000, the State Water Board adopted Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (State Implementation Policy or SIP). The SIP became effective on April 28, 2000, with respect to the priority pollutant criteria promulgated for California by the U.S. EPA through the NTR and to the priority pollutant objectives established by the Central Coast Water Board in the Basin Plan. The SIP became effective on May 18, 2000, with respect to the priority pollutant criteria promulgated by the U.S. EPA through the CTR. The State Water Board adopted amendments to the SIP on February 24, 2005, that became effective on July 13, 2005. 3.3.6 Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (ISWEBE Plan). The ISWEBE Plan includes several parts and sections that have been adopted by the State Water Board over time. The applicable parts and sections are discussed below. On May 2, 2017, the State Water Board adopted and ISWEBE Plan Part 2: Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. With ISWEBE Plan Part 2’s approval, the State Water Board approved one new narrative and four new numeric mercury water quality objectives to apply to those inland surface waters, enclosed bays, and estuaries of the state that have any of the following beneficial use designations: COMM, CUL, T-SUB, WILD, MAR, RARE, WARM, COLD, EST, or SAL. The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On August 7, 2018, the State Water Board adopted ISWEBE Plan Part 3: Bacteria Provisions and a Water Quality Standards Variance Policy, which establishes water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On December 1, 2020, the State Water Board adopted the Aquatic Toxicity Provisions, which are incorporated into the ISWEBE Plan. On October 5, 2021, the State Water Board adopted a resolution to confirm that the Aquatic Toxicity Provisions were adopted as state policy for water quality control for all inland surface waters, enclosed bays, estuaries, and coastal lagoons of the state. The provisions were approved by the California Office of Administrative Law on April 25, 2022 and were approved by the U.S. EPA on May 1, 2023. The provisions include statewide numeric water quality objectives for both acute and chronic toxicity and a program of implementation to control toxicity. The provisions provide consistent protection of aquatic life beneficial uses in inland surface waters, enclosed bays, estuaries, and coastal lagoons throughout the state from the effects of known and unknown toxicants. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-14 This Order is consistent with the ISWEBE Plan and includes effluent limitations for mercury, bacteria, and chronic toxicity. 3.3.6. Domestic Water Quality. In compliance with California Water Code section 106.3, it is the policy of the State of California that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. This Order promotes that policy by requiring discharges to meet water quality objectives established in the Basin Plan that are based on drinking water maximum contaminant levels and designed to protect human health and ensure that water is safe for domestic use. 3.3.7. Antidegradation Policy. Federal regulation 40 C.F.R. section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal policy. The State Water Board established California’s antidegradation policy in State Water Board Resolution 68-16, Statement of Policy with Respect to Maintaining High Quality of Waters in California . Resolution 68-16 is deemed to incorporate the federal antidegradation policy where the federal policy applies under federal law. Resolution 68-16 requires that existing water quality be maintained unless degradation is justified by specific findings. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The permitted discharge must be consistent with the antidegradation provision of 40 C.F.R. section 131.12 and State Water Board Resolution 68-16. 3.3.8. Anti-Backsliding Requirements. Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. section 122.44(l) restrict backsliding in NPDES permits. These anti-backsliding provisions require that effluent limitations in a reissued permit must be as stringent as those in the previous permit, with some exceptions in which limitations may be relaxed. 3.3.9. Endangered Species Act Requirements. This Order does not authorize any act that results in the taking of a threatened or endangered species or any act that is now prohibited, or becomes prohibited in the future, under either the California Endangered Species Act (Fish and Game Code sections 2050 to 2097) or the Federal Endangered Species Act (16 U.S.C. sections 1531 to 1544). This Order requires compliance with effluent limits, receiving water limits, and other requirements to protect the beneficial uses of waters of the state. The Discharger is responsible for meeting all applicable requirements of the endangered species acts. 3.3.10. Sewage Sludge and Biosolids. This Order does not authorize any act that results in violation of requirements administered by U.S. EPA to implement 40 C.F.R. part 503, Standards for the Use or Disposal of Sewage Sludge. These standards regulate the final use or disposal of sewage sludge that is generated during the treatment of domestic sewage in a municipal wastewater treatment facility. The Discharger is responsible for meeting all applicable requirements of 40 C.F.R. part 503 that are under U.S. EPA’s enforcement authority. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-15 3.4. Impaired Waterbodies on the CWA section 303(d) List CWA section 303(d) requires states to identify and make a list of specific water bodies where water quality standards are not expected to be met after implementation of technology-based effluent limitations on point sources. For all CWA section 303(d) listed water bodies and pollutants, the Central Coast Water Board must develop and implement total maximum daily loads (TMDLs) that specify waste load allocations (WLAs) for point sources and load allocations (LAs) for non- point sources. The U.S. EPA approved the State’s 2020-2022 303(d) list of impaired water bodies on May 11, 2022. The 2020-2022 303(d) list identifies San Luis Obispo Creek, below Osos Street, as impaired for chloride, sodium, benthic community effects, Escherichia coli (E. coli), dissolved oxygen, nitrate, and toxicity. A TMDL for nitrate was adopted for San Luis Obispo Creek below West Marsh Street. Effluent limitations for nitrate in this Permit are based on Central Coast Water Board Resolution R3-2005-0106 (TMDL for nitrate). A TMDL for pathogens was adopted for San Luis Obispo Creek (R3-2004-0142) but the Facility was not identified as a source and was not assigned a wasteload allocation. However, the Discharger is implementing a Wasteload Allocation Attainment Plan (WAAP) to address pathogens from the sources identified in the TMDL. 3.5. Other Plans, Polices and Regulations 3.5.1. State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001, Waste Discharge Requirements for Stormwater Associated with Industrial Activities Excluding Construction Activities (Industrial General Permit). The Industrial General Permit, adopted April 1, 2014, amended August 4, 2015, and November 6, 2018, and effective July 1, 2015, is applicable to POTWs with a design capacity greater than 1.0 MGD. The purpose of the Industrial General Order is to regulate stormwater discharges associated with industrial activities. For the control of stormwater discharged from the Facility, the Discharger has enrolled in and is regulated by the Industrial General Permit. 3.5.2. State Water Board Order. 2022-0103-DWQ Statewide General Waste Discharge Requirements for Sanitary Sewer Systems. State Water Board Order No. 2022-0103-DWQ, adopted on December 6, 2022, is applicable to all "federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California." The purpose of Water Quality Order 2022-0103-DWQ is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled in Water Quality Order 2022-0103-DWQ and must comply with its requirements and any requirements in reissuances to Water Quality Order 2022-0103-DWQ. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-16 3.5.3. State Water Board Recycled Water Policy. The State Water Board adopted the Quality Control Policy for Recycled Water (Recycled Water Policy) on December 11, 2018, and it became effective on April 8, 2019. The purpose of the Recycled Water Policy is to encourage the safe use of recycled water in a manner that is protective of public health and the environment. This Order implements the Recycled Water Policy by supporting the production of recycled water and requiring volumetric reporting of wastewater and recycled water to the State Water Board. The Recycled Water Policy calls for the development of regional groundwater basin/sub-basin salt/nutrient management plans. This Order requires the Discharger to continue to commit funding and in-kind resources to facilitate development of a regional groundwater basin/sub-basin salt/nutrient management plan that implements the Recycled Water Policy. 3.5.4 Statewide General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW). State Water Board Order WQ 2016-0068-DDW, adopted on June 7, 2016, is applicable to recycled water projects where recycled water is used or transported for non -potable uses. The distribution and offsite reuse of recycled water produced by the Facility is subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. 3.5.5 Environmental Justice and Advancing Racial Equity. When issuing or reissuing individual waste discharge requirements or waivers of waste discharge requirements that regulate an activity or a facility that may impact a disadvantaged or tribal community, and that includes a time schedule in accordance with subdivision (c) of Section 13263 for achieving an applicable water quality objective, an alternative compliance path that allows time to come into compliance with water quality objectives, or a water quality variance, the Central Coast Water Board shall make a finding on potential environmental justice, tribal impact, and racial equity considerations. (Water Code § 13149.2, effective Jan. 1, 2023). Water Code section 189.7 requires the Central Coast Water Board to conduct outreach in disadvantaged and/or tribal communities when adopting individual waste discharge requirements. In accordance with the Water Boards’ efforts to advance racial equity, the Central Coast Water Board is also committed to developing and implementing policies and programs to advance racial equity and environmental justice so that race can no longer be used to predict life outcomes, and outcomes for all groups are improved. Upon review of readily available information, the Central Coast Water Board finds that this Order regulates a discharge that does not disproportionately impact the water quality of an economically disadvantaged community or a tribal community. Similarly, this Order does not include a time schedule, alternative compliance path, or variance. Therefore, Water Code section 13149.2 does not apply to this permit reissuance. Nevertheless, the Central Coast Water Board has conducted outreach consistent with Water Code section 189.7 by reaching out to surrounding communities and tribal communities about this Order. Additionally, the Board has considered any environmental justice concerns within the Board’s authority, in accordance with the Water Boards’ efforts to advance racial equity. The Order CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-17 requires the Permittee to meet water quality standards to protect public health and the environment, thereby benefiting all persons and communities within the Region. 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS The CWA requires point source dischargers to control the amount of conventional, non-conventional, and toxic pollutants that are discharged into the waters of the United States. The control of pollutants discharged is established through effluent limitations and other requirements in NPDES permits. There are two principal bases for effluent limitations in the Code of Federal Regulations: 40 C.F.R. section 122.44(a) requires that permits include applicable technology-based limitations and standards, and 40 C.F.R. section 122.44(d) requires that permits include water quality-based effluent limitations to attain and maintain applicable numeric and narrative water quality criteria to protect the beneficial uses of receiving waters. When numeric water quality objectives have not been established, but a discharge has the reasonable potential to cause or contribute to exceedances of water quality standards described at 40 C.F.R. section 122.44 (d), then 1) water quality based effluent limitations (WQBELS) may be established using a calculated water quality criterion derived from a proposed state criterion or an explicit State policy or regulation interpreting its narrative criterion, 2) WQBELs may be established on a case-by-case basis using U.S. EPA criteria guidance published under CWA Section 304 (a), or 3) WQBELs may be established using an indicator parameter for the pollutant of concern. Several specific factors affecting the development of limitations and requirements in this Order are discussed below. 4.1. Discharge Prohibitions 4.1.1. Discharge Prohibition 3.1. (No discharge at a location or in a manner except as described by the Order). The Order authorizes a single, specific point of discharge to surface waters, and the limitations and conditions established by the Order are based on specific information provided by the Discharger and gained by the Central Coast Water Board through site visits, review of monitoring reports, and other information. Discharges to surface waters at locations not contemplated by this Order or discharges of a character not contemplated by this Order are therefore viewed as inconsistent with CWA section 402’s prohibition against discharges of pollutants except in compliance with the CWA’s permit requirements, effluent limitations, and other enumerated provisions. This prohibition is retained from the previous permit. 4.1.2. Discharge Prohibition 3.2. (Discharge of any waste not specifically regulated by this Order is prohibited). Because limitations and conditions of the Order are based on specific information provided by the Discharger and specific wastes described by the Discharger, the limitations and conditions of the Order do not adequately address waste streams not contemplated during drafting of the Order. To prevent the discharge of such waste streams that may be inadequately CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-18 regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.1.3. Discharge Prohibition 3.3. (Overflow, bypass, or overspray of wastewater from the Discharger’s facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7. (Bypass), is prohibited). The discharge of untreated or partially treated wastewater from the Discharger’s collection, treatment, or disposal facilities represents an unauthorized bypass pursuant to 40 C.F.R. section 122.41(m) or an unauthorized discharge that poses a threat to human health and/or aquatic life, and, therefore, is explicitly prohibited by this Order. 4.1.4. Discharge Prohibition 3.4. (Creation of a condition of pollution, contamination, or nuisance, as defined by Section 13050 of the California Water Code, is prohibited). The Basin Plan requires that the disposal of wastewater to waterbodies be accomplished in a manner that safeguards public health and prevents nuisance conditions. 4.1.5. Discharge Prohibition 3.5. (Discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat). This prohibition is consistent with the requirements of the Basin Plan. 4.1.6. Discharge Prohibition 3.6. (Discharge of radioactive substances is prohibited). This prohibition is consistent with the requirements of the Basin Plan. 4.1.7. Discharge Prohibition 3.7. (Monthly average dry weather effluent flow shall not exceed 5.4 million gallons per day (MGD), aggregated at Discharge Point 001). To prevent the discharge of such waste streams that may be inadequately regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.2. Technology-Based Effluent Limitations 4.2.1. Scope and Authority Section 301(b) of the CWA and implementing U.S. EPA permit regulations at 40 C.F.R. § 122.44 require that permits include conditions meeting applicable technology-based requirements at a minimum, and any more stringent effluent limitations necessary to meet applicable water quality standards. Where the USEPA has not yet developed technology-based standards for a particular industry or a particular pollutant, CWA Section 402 (a) (1) and USEPA regulations at 40 C.F.R. § 125.3 authorize the use of best professional judgment (BPJ) to derive technology-based effluent limitations on a case-by-case basis. When BPJ is used, the permit writer must consider specific factors outlined at 40 C.F.R. § 125.3. Regulations promulgated in 40 C.F.R. § 125.3(a)(1) require technology- based effluent limitations for municipal dischargers to be placed in NPDES permits based on Secondary Treatment Standards or Equivalent to Secondary Treatment Standards. The Federal Water Pollution Control Act Amendments of 1972 (PL 92-500) established the minimum performance requirements for POTWs [defined in section 304(d)(1)]. Section 301(b)(1)(B) of that act requires CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-19 that such treatment works must, as a minimum, meet effluent limitations based on secondary treatment as defined by the U.S. EPA Administrator. Based on this statutory requirement, U.S. EPA developed secondary treatment regulations, which are specified in 40 C.F.R. part 133. These technology-based regulations apply to all municipal wastewater treatment plants and identify the minimum level of effluent quality attainable by secondary treatment in terms of biochemical oxygen demand (BOD5), total suspended solids (TSS), and pH. The discharge authorized by this Order must meet minimum federal technology-based requirements based on Secondary Treatment Standards at 40 C.F.R. part 133 , summarized below: Table F-6. Secondary Treatment Requirements Parameter Units 30-Day Average 7-Day Average BOD5 [1] mg/L 30 45 TSS[1] mg/L 30 45 pH standard units 6.0[2] 9.0[3] [1] The 30-day average percent removal shall not be less than 85 percent. [2] Instantaneous minimum value. [3] Instantaneous maximum value. 4.2.2. Applicable Technology-Based Effluent Limitations 40 C.F.R. section122.45(f)(1) requires effluent limitations be expressed in terms of mass, with some exceptions, and 40 C.F.R. section 122.45(f)(2) allows pollutants that are limited in terms of mass to additionally be limited in terms of other units of measurement. This Order includes effluent limitations expressed in terms of mass and concentration. In addition, pursuant to the exceptio ns to mass limitations provided in 40 C.F.R. section 122.45(f)(1), some effluent limitations are not expressed in terms of mass, such as pH and temperature, as well as when the applicable standards are expressed in terms of concentration and mass limitations are not necessary to protect the beneficial uses of the receiving waters. 4.2.2.1. The following table summarizes technology-based effluent limitations established by this Order at Discharge Point 001. Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 Parameter Units 30-Day Average 7-Day Average Maximum Daily BOD5[1] mg/L 10 30 50 BOD5 lbs/day [2] 450 1,351 2,252 Total Suspended Solids (TSS)[1] mg/L 10 30 75 TSS lbs/day[2] 450 1,351 3,378 [1] The average monthly percent removal of BOD5 and TSS, as measured at Monitoring Location EFF-001, shall not be less than 85 percent. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-20 [2] Mass loading limits were calculated using the following formulas: lbs/day = pollutant concentration (mg/L) * permitted flow (5.4 MGD) * conversion factor (8.34) [3] Instantaneous minimum value. [4] Instantaneous maximum value. 4.2.2.1.1. BOD5 and TSS. BOD and TSS. Federal regulations, 40 C.F.R. part 133, establish the minimum weekly and monthly average level of effluent quality attainable by secondary treatment for BOD5 and TSS. The Central Coast Water Board has determined that tertiary treatment is necessary to protect the beneficial uses of the receiving stream, thus the final effluent limitations for BOD5 and TSS are based on the technical capability of the tertiary process. The secondary and tertiary treatment standards for BOD5 and TSS are indicators of the effectiveness of the treatment processes. The principal design parameter for wastewater treatment plants is the daily BOD5 and TSS loading rates and the corresponding removal rate of the system. In applying 40 C.F.R. part 133 for weekly and monthly average BOD5 and TSS limitations, the application of tertiary treatment processes results in the ability to achieve lower levels for BOD5 and TSS than the secondary standards currently prescribed; the 30 -day average BOD5 and TSS limitations are 10 mg/L, the 7-day average BOD5 and TSS limitations are 30 mg/L. These effluent limitations are based on the capability of a tertiary system. In addition to the average weekly and average monthly effluent limitations, daily maximum effluent limitation of 50 mg/L and 75 mg/L for BOD5 and TSS, respectively, are included in the Order to ensure that the treatment works are not organically overloaded and operate in accordance with design capabilities. In addition, 40 C.F.R. § 133.102, in describing the minimum level of effluent quality attainable by secondary treatment, states that the 30-day average percent removal shall not be less than 85 percent. If 85 percent removal of BOD5 and TSS must be achieved by a secondary treatment plant, it must also be achieved by a tertiary (i.e., treatment beyond secondary level) treatment plant. This Order contains a limitation requiring an average of 85 percent removal of BOD5 and TSS over each calendar month. These effluent limitations are carried over from Order R3-2014-0033. 4.3. Water Quality-Based Effluent Limitations (WQBELs) 4.3.1. Scope and Authority CWA section 301(b) and 40 C.F.R. section 122.44(d) require that permits include limitations more stringent than applicable federal technology -based requirements where necessary to achieve applicable water quality standards. Section 122.44(d)(1)(i) of 40 C.F.R. requires that permits include effluent limitations for all pollutants that are or may be discharged at levels that have the reasonable potential to cause or contribute to an exceedance of a water quality standard, including numeric and narrative objectives within a standard. Where reasonable potential has been established for a pollutant, but there is no numeric criterion or objective for the pollutant, WQBELs must be established using: (1) U.S. EPA criteria guidance under CWA section 304(a), supplemented where CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-21 necessary by other relevant information; (2) an indicator parameter for the pollutant of concern; or (3) a calculated numeric water quality criterion, such as a proposed state criterion or policy interpreting the state’s narrative criterion, supplemented with other relevant information, as provided in section 122.44(d)(1)(vi). The process for determining reasonable potential and calculating WQBELs when necessary is intended to protect the designated uses of the receiving water as specified in the Basin Plan and to achieve applicable water quality objectives and criteria that are contained in other state plans and policies, or any applicable water quality criteria contained in the CTR and NTR. 4.3.2. Applicable Beneficial Uses and Water Quality Criteria and Objectives Beneficial uses described by the 2019 Basin Plan for San Luis Obispo Creek and they are presented in section 3.3.1 of this Fact Sheet. Water quality criteria applicable to this receiving water are established by the CTR, the NTR, and by the 2019 Basin Plan. 4.3.3. Determining the Need for WQBELs NPDES regulations at 40 CFR section 122.44(d) require effluent limitations to control all pollutants which are or may be discharged at a level which will cause, have the reasonable potential to cause, or contribute to an excursion above any State water quality standard. The SIP, the statewide policy that became effective on May 22, 2000, establishes procedures to implement water quality criteria from the NTR and CTR and for priority, toxic pollutant objectives established in the Basin Plan. The implementation procedures of the SIP include methods to determine reasonable potential (for pollutants to cause or contribute to excursions above State water quality standards) and to establish numeric effluent limitations, if necessary, for those pollutants which show reasonable potential. The SIP Section 1.3 requires the Central Coast Water Board to use all available valid, relevant, and representative receiving water and effluent data and information to conduct a reasonable potential analysis (RPA). The Central Coast Water Board analyzed the Discharger’s data for priority pollutants and the nature of the discharge to determine if the discharge has reasonable potential to exceed water quality standards. The RPA is based on effluent data retrieved from CIWQS from the period of December 2014 to December 2022. Some freshwater water quality criteria for metals are hardness dependent, i.e., as hardness decreases, the toxicity of certain metals increases, and the applicable water quality criteria become correspondingly more stringent. The Discharger has not specifically collected hardness data for the receiving water. However, the Central Coast Water Board’s Central Coast Ambient Monitoring Program has nearby monitoring stations on San Luis Obispo Creek that has collected this information. The Water Board used 330 mg/L as CaCO3 as a conservative estimate of the receiving water hardness to determine hardness-based criteria. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-22 To conduct the RPA, the Central Coast Water Board identified the maximum observed effluent (MEC) and background (B) concentrations for each priority, toxic pollutant from receiving water and effluent data provided by the Discharger and compared this data to the most stringent applicable water quality criterion (C) for each pollutant from the NTR, CTR, and the 2019 Basin Plan. The Discharger did not collect background data (B) for receiving water. Section 1.3 of the SIP establishes three triggers for a finding of reasonable potential. 4.3.3.1. Trigger 1. If the MEC is greater than C, there is reasonable potential, and an effluent limitation is required. 4.3.3.2. Trigger 2. If B is greater than C, and the pollutant is detected in effluent (MEC > ND), there is reasonable potential, and an effluent limitation is required. 4.3.3.3. Trigger 3. After reviewing other available and relevant information, a permit writer may decide that a WQBEL is required. Such additional information may include, but is not limited to: the facility type, the discharge type, solids loading analyses, lack of dilution, history of compliance problems, potential toxic impact of the discharge, fish tissue residue data, water quality and beneficial uses of the receiving water, CWA 303(d) listing for the pollutant, and the presence of endangered or threatened species or their critical habitat. For mercury in particular, Part 2 of the SIP revised the above methodology as follows, pursuant to State Water Board Resolution 2017-0027, Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California-Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions (Mercury Provisions). 4.3.3.4. Most stringent water quality objective. The RPA is to use a water column concentration from SIP Part 2’s Table 1 based on the receiving water body type and beneficial use(s) to identify the most stringent mercury water quality objective. For San Luis Obispo Creek, the applicable water column concentration is 0.012 ug/L total mercury. This water column concentration is to be used as the “C” value in the RPA for mercury. This change in methodology changes the water quality objective from 0.05 ug/L in the previous orders to 0.012 ug/L in this Order. 4.3.3.5. Maximum Effluent Concentration. Instead of using the highest observed mercury effluent concentration, the MEC is to be determined as an arithmetic mean of all mercury samples during a calendar year. For this RPA, the highest calendar year arithmetic mean based on the revised methodology for mercury in effluent was 0.03 ug/L. The Discharger collects effluent mercury samples on a yearly basis. 4.3.3.6. Maximum ambient background concentration. Instead of using the highest observed mercury concentration in the upstream receiving water (referred to as “B”), the value of B is to be determined as an arithmetic mean of all mercury samples during a calendar year. This Discharger did not sample for and does not have ambient background concentration data for mercury. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-23 4.3.3.7. Determination. A mercury WQBEL is not required unless the MEC is greater than C. However, if B is greater than C and mercury is detected in the effluent, effluent monitoring is required. A mercury WQBEL is required for this discharge because the MEC (i.e., the highest calendar year average concentration with using one half the mercury detection limits when non -detect) was greater than C and there was no B data available. Therefore, according to Part 2 of the SIP, a mercury effluent limitation is required. Annual monitoring for mercury will be retained from the previous Order. The following table summarizes the RPA for each priority, title 22, or Basin Plan pollutant for which data was available from December 2014 through December 2022 and sets forth the basis upon which WQBELs are included in this Order. Table F-8. Summary of RPA Results CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Priority Pollutants 1 Antimony, Total Recoverable µg/L 9 2.5 6 - No Primary MCL 2 Arsenic, Total Recoverable µg/L 9 <2.0 10 - No Primary MCL 3 Beryllium µg/L 9 <0.2 4 - No Primary MCL 4 Cadmium, Total Recoverable µg/L 9 <0.2 3 - No CA Prim. MCL 5a Chromium (III) µg/L 7 7.0 50 - No CA Prim. MCL for Chromium (Total) 5b Chromium (VI) µg/L 8 1.1 11 - No CTR - Chronic 6 Copper, Total Recoverable µg/L 9 24 26 - No CTR - Chronic 7 Lead, Total Recoverable µg/L 8 6.3 15 - No CA Prim. MCL 8 Mercury, Total Recoverable µg/L 9 0.03 0.012 - Yes Mercury Provisions 9 Nickel, Total Recoverable µg/L 9 7.0 100 - No CA Prim. MCL 10 Selenium, Total Recoverable µg/L 9 1.0 5 - No CTR - Chronic CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-24 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 11 Silver, Total Recoverable µg/L 8 <0.25 31.6 - No CTR - Acute 12 Thallium, Total Recoverable µg/L 9 <0.2 1.7 - No CTR 13 Zinc, Total Recoverable µg/L 9 100 330 - No CTR 14 Cyanide, Total (as CN) µg/L 9 <4.0 5.2 - No CTR 15 Asbestos Million Fibers/L 9 <0.2 7 - No CTR 16 2,3,7,8 TCDD µg/L 9 <0.00000 0251 0.00000001 3 - Ud CTR 17 Acrolein µg/L 8 <5.0 320 - No CTR 18 Acrylonitrile µg/L 8 <2.0 0.059 - Ud CTR 19 Benzene µg/L 9 <0.5 1 - No CA Prim. MCL 20 Bromoform µg/L 73 1.1 4.3 - No CTR 21 Carbon Tetrachloride µg/L 9 <0.5 0.25 - Ud CTR 22 Chlorobenzene µg/L 9 <0.5 70 - No CA Prim. MCL 23 Chlorodibromomethane (aka Dibromochloromethane) µg/L 73 5.4 0.401 - Yes CTR 24 Chloroethane µg/L 8 <0.5 No Criteria - Uc No criteria 25 2-Chloroethylvinyl ether µg/L 8 <1.0 No Criteria - Uc No criteria 26 Chloroform µg/L 8 95.7 60 - Yes NAWQC 27 Dichlorobromomethane µg/L 73 24.8 0.56 - Yes CTR 28 1,1-Dichloroethane µg/L 9 <0.5 5 - No Primary MCL 29 1,2-Dichloroethane µg/L 9 <0.5 0.38 - Ud CTR 30 1,1-Dichloroethylene µg/L 9 <0.5 0.057 - No CTR 31 1,2-Dichloropropane µg/L 9 <0.5 0.52 - No CTR 32 1,3-Dichloropropylene µg/L 1 <0.5 0.5 - No CA Prim. MCL 33 Ethylbenzene µg/L 9 <0.5 300 - No CA Prim. MCL 34 Methyl Bromide (aka Bromomethane) µg/L 8 <0.5 48 - No CTR 35 Methyl Chloride (aka chloromethane) µg/L 8 <0.5 No Criteria - Uc No criteria 36 Methylene Chloride µg/L 9 15 4.7 - Yes CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-25 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 37 1,1,2,2-Tetrachloroethane µg/L 9 <0.5 0.17 - Ud CTR Tetrachloroethylene (aka Tetrachloroethene) µg/L 7 <0.5 0.8 - No CTR 39 Toluene µg/L 9 <0.5 150 - No CA Prim. MCL 40 1,2-Trans-Dichloroethylene µg/L 7 <0.005 10 - No CA Prim. MCL 41 1,1,1-Trichloroethane µg/L 9 <0.5 200 - No CA Prim. MCL 42 1,1,2-Trichloroethane µg/L 9 <0.5 0.6 - No CTR 43 Trichloroethylene (aka Trichloroethene) µg/L 7 <0.5 2.7 - No CTR 44 Vinyl Chloride µg/L 9 <0.5 0.5 - No CA Prim. MCL 45 2-Chlorophenol µg/L 8 <2.0 120 - No CTR 46 2,4-Dichlorophenol µg/L 8 <2.0 93 - No CTR 47 2,4-Dimethylphenol µg/L 8 <1.0 540 - No CTR 48 4,6-dinitro-o-resol (aka 2-methyl-4,6- Dinitrophenol aka 4,6-Dinitro-2- methylphenol) µg/L 7 <1.0 13.4 - No CTR 49 2,4-Dinitrophenol µg/L 8 <5.0 70 - No CTR 50 2-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 51 4-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 52 3-Methyl-4-Chlorophenol (aka P-chloro-m-resol aka 4-Chloro-3- methylphenol) µg/L 8 <1.0 No Criteria - Uc No criteria 53 Pentachlorophenol µg/L 34 2 0.28 - Yes CTR 54 Phenol, Single Compound µg/L 1 <1.0 1 - No BP 55 2,4,6-Trichlorophenol µg/L 8 <1.0 2.1 - No CTR 56 Acenaphthene µg/L 8 <1.0 1200 - No CTR 57 Acenaphthylene µg/L 8 <1.0 No Criteria - Uc No criteria 58 Anthracene µg/L 8 <1.0 9600 - No CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-26 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 59 Benzidine µg/L 8 <1.0 0.00012 - Ud CTR 60 Benzo(a)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 61 Benzo(a)Pyrene µg/L 9 <0.1 0.0044 - Ud CTR 62 Benzo(b)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 63 Benzo(ghi)Perylene µg/L 8 <1.0 No Criteria - Uc No criteria 64 Benzo(k)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 65 Bis(2- Chloroethoxy)Methane µg/L 8 <1.0 No Criteria - Uc No criteria 66 Bis(2-Chloroethyl)Ether µg/L 8 <1.0 0.031 - Ud CTR 67 Bis(2-Chloroisopropyl)Ether µg/L 8 <1.0 1400 - No CTR 68 Bis(2-Ethylhexyl) Phthalate (aka Di(2-ethylhexyl) Phthalate) µg/L 9 <2.0 1.8 - Ud CTR 69 4-Bromophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 70 Butylbenzyl Phthalate µg/L 8 <1.0 3000 - No CTR 71 2-Chloronaphthalene µg/L 8 <1.0 1700 - No CTR 72 4-Chlorophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 73 Chrysene µg/L 8 <1.0 0.0044 - Ud CTR 74 Dibenzo(a,h)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 75 1,2-Dichlorobenzene µg/L 10 <0.5 600 - No CA Prim. MCL 76 1,3-Dichlorobenzene µg/L 9 <0.5 400 - No CTR 77 1,4-Dichlorobenzene µg/L 10 <0.5 5 - No CA Prim. MCL 78 3,3 Dichlorobenzidine µg/L 8 <1.0 0.04 - Ud CTR 79 Diethyl Phthalate µg/L 8 <1.0 23000 - Ud CTR 80 Dimethyl Phthalate µg/L 8 <1.0 313000 - No CTR 81 Di-n-Butyl Phthalate µg/L 8 <1.0 2700 - No CTR 82 2,4-Dinitrotoluene µg/L 8 <1.0 0.11 - Ud CTR 83 2,6-Dinitrotoluene µg/L 8 <1.0 No Criteria - Uc No criteria 84 Di-n-Octyl Phthalate µg/L 8 <1.0 No Criteria - Uc No criteria CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-27 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 85 1,2-Diphenylhydrazine µg/L 8 <1.0 0.04 - Ud CTR 86 Fluoranthene µg/L 8 <1.0 300 - No CTR 87 Fluorene µg/L 8 <1.0 1300 - No CTR 88 Hexachlorobenzene µg/L 8 <1.0 0.00075 - Ud CTR 89 Hexachlorobutadiene µg/L 8 <1.0 0.44 - Ud CTR 90 Hexachlorocyclopentadiene µg/L 8 <1.0 50 - No CA Prim. MCL 91 Hexachloroethane µg/L 8 <1.0 1.9 - No CTR 92 Indeno(1,2,3-cd)Pyrene µg/L 8 <1.0 0.0044 - Ud CTR 93 Isophorone µg/L 8 <1.0 8.4 - No CTR 94 Naphthalene µg/L 8 <1.0 No Criteria - Uc No criteria 95 Nitrobenzene µg/L 8 <1.0 17 - No CTR 96 N-Nitrosodimethylamine µg/L 35 <0.001 0.00069 - No CTR 97 N-Nitrosodi-n-Propylamine µg/L 8 <1.0 0.005 - Ud CTR 98 N-Nitrosodiphenylamine µg/L 8 <1.0 5 - No CTR 99 Phenanthrene µg/L 8 <1.0 No Criteria - Uc No criteria 100 Pyrene µg/L 8 <1.0 960 - No CTR 101 1,2,4-Trichlorobenzene µg/L 9 <0.5 5 - No CA Prim. MCL 102 Aldrin µg/L 9 <0.005 0.00013 - Ud CTR 103 alpha-BHC µg/L 8 <0.005 0.0039 - Ud CTR 104 beta-BHC µg/L 8 <0.005 0.014 - No CTR 105 gamma-BHC µg/L 10 <0.005 0.019 - No CTR 106 delta-BHC µg/L 8 <0.005 No Criteria - Uc No criteria 107 Chlordane µg/L 9 <0.047 0.00057 - Ud CTR 108 4,4'-DDT µg/L 8 <0.005 0.00059 - Ud CTR 109 4,4'-DDE µg/L 8 <0.005 0.00059 - Ud CTR 110 4,4'-DDD µg/L 8 <0.005 0.00083 - Ud CTR 111 Dieldrin µg/L 9 <0.005 0.00014 - Ud CTR 112 alpha-Endosulfan µg/L 8 <0.005 0.056 - No CTR 113 beta-Endolsulfan µg/L 8 <0.005 0.056 - No CTR 114 Endosulfan Sulfate µg/L 8 <0.005 110 - No CTR 115 Endrin µg/L 10 <0.005 0.036 - No CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-28 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 116 Endrin Aldehyde µg/L 7 <0.005 0.76 - No CTR 117 Heptachlor µg/L 10 <0.005 0.00021 - Ud CTR 118 Heptachlor Epoxide µg/L 10 <0.005 0.00011 - Ud CTR 119- 125 PCBs sum µg/L 2 <0.5 0.00017 - Ud CTR 126 Toxaphene µg/L 9 <0.24 0.0002 - Ud CTR Non-Priority Pollutants Drinking Water Quality Objectives Aluminum µg/L 9 150 200 - No CA Sec. MCL Barium µg/L 9 42.9 1000 - No CA Prim. MCL Fluoride mg/L 9 0.7 1 - No BP Nitrate, Total (as N) mg/L 151 51.7 10 8.1 Yes EPA Prim. MCL Nitrate + Nitrite (as N) mg/L 7 43.4 10 - Yes CA Prim. MCL Nitrite, Total (as N) mg/L 106 5.1 1 <0.1 Yes CA Prim. MCL Methyl-tert-butyl ether µg/L 9 <1.0 5 - No CA Sec. MCL Styrene µg/L 9 <0.5 100 - No CA Prim. MCL Alachlor µg/L 9 <0.1 2 - No CA Prim. MCL Atrazine µg/L 9 <0.1 1 - No CA Prim. MCL Bentazon µg/L 9 <2.0 18 - No CA Prim. MCL Carbofuran µg/L 9 <5.0 18 - No CA Prim. MCL 2,4-D µg/L 9 5 70 - No CA Prim. MCL Dalapon µg/L 9 <10.0 200 - No CA Prim. MCL Dibromochloropropane (aka 1,2-Dibromo-3- Chloropropane) µg/L 8 <0.01 0.2 - No CA Prim. MCL Di(2-ethylhexyl)adipate µg/L 9 <5.0 400 - No CA Prim. MCL Dinoseb µg/L 9 <1.0 7 - No CA Prim. MCL Diquat µg/L 9 <2.0 20 - No CA Prim. MCL Endothall µg/L 9 <40 100 - No CA Prim. MCL Ethylene Dibromide (aka 1,2-Dibromoethane) µg/L 8 <0.02 0.05 - No CA Prim. MCL CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-29 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Glyphosate µg/L 9 <20.0 700 - No CA Prim. MCL Methoxychlor µg/L 10 <0.1 30 - No CA Prim. MCL Molinate µg/L 9 <0.1 20 - No CA Prim. MCL Oxamyl µg/L 9 <5.0 50 - No CA Prim. MCL Picloram µg/L 9 <1.0 500 - No CA Prim. MCL Simazine µg/L 9 <0.1 4 - No CA Prim. MCL Thiobencarb µg/L 9 <0.1 70 - No CA Prim. MCL 2,4,5-TP (Silvex) µg/L 9 <1.0 50 - No CA Prim. MCL Trichlorofluoromethane µg/L 9 <0.5 150 - No CA Prim. MCL 1,1,2-Trichloro-1,2,2- Trifluoroethane µg/L 3 <0.5 1200 - No CA Prim. MCL Xylenes µg/L 9 <0.5 1750 - No CA Prim. MCL Methylene blue activated substances (MBAS) µg/L 8 800 200 - Yes BP Un-ionized Ammonia (as N) mg/L [5] [5] 0.025 - Yes[5] BP Board 3 Basin Plan Water Quality Objectives for Agricultural Water Use Boron, Total µg/L 7 260 750 - No BP Cobalt, Total µg/L 7 4.0 50 - No BP Iron, Total µg/L 8 520 5000 - No BP Lithium, Total µg/L 7 14 2500d - No BP Manganese, Total µg/L 8 42.8 200 - No BP Molybdenum, Total µg/L 7 17 10 - Yes BP Vanadium, Total µg/L 7 5 100 - No BP San Luis Obispo Creek Sub-Area Surface Water Quality Objectives Total Dissolved Solids mg/L 38 990 650 470- 750[6] Yes BP Chloride mg/L 39 209 100 31- 92[6] Yes BP Sulfate, Total, (as SO4) mg/L 6 142 100 - Yes BP Sodium mg/L 35 181 50 29- 72[6] Yes BP [1] Number of data points available for the RPA. [2] If there is a detected value, the highest reported value is summarized in the table. If there are no detected values, if available, the lowest MDL is summarized in the table. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-30 [3] RPA Results: = Yes, if MEC > WQO/WQC, or B > WQO/WQC and MEC is detected; = No, if MEC and B are < WQO/WQC or all effluent data are undetected; = (Uc) Undetermined, if no criteria have been promulgated; = (Ud) Undetermined, for lack of data. As described in section 1.3 in the SIP, if monitoring results show non-detect for all samples of a pollutant and if all reported detection limits of the pollutant in the effluent are greater than or equal to the C value, the RWQCB shall require additional monitoring for the pollutant in place of a water quality-based effluent limitation. For pollutants with a result of Ud, additional monitoring is established through this permit. [4] Basis of Most Stringent Criteria CTR - California Toxics Rule’ CA Prim. MCL - California Primary MCL CA Sec. MCL - California Secondary MCL EPA Prim. MCL - EPA Primary MCL EPA Sec. MCL - EPA Secondary MCL NAWQC - National Ambient Water Quality Criteria BP - Central Coast Regional Board 2019 Basin Plan SWRCB 2017-0027 - Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California—Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. [5] The reasonable potential for the effluent to exceed the 2019 Basin Plan water quality objective for San Luis Obispo Creek for un-ionized ammonia is based on 93 concurrent upstream (RSW-004) and downstream (RSW-005) monitoring data results from December 2014 through April 2020. [6] Range of measured values. The 2019 Basin Plan Water Quality Objective for this pollutant is an annual mean. 4.3.4. WQBEL Calculations As detailed in Table F-6, reasonable potential has been determined for mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, total nitrate (as N), nitrate + nitrite (as N), total nitrite (as N), un- ionized ammonia (as N), methylene blue activated substances (MBAS), total molybdenum, total dissolved solids (TDS), sulfate, sodium, and chloride. The following example demonstrates how WQBELs were established for this Order for chlorodibromomethane. Step 1: For each water quality criterion/objective, an effluent concentration allowance (ECA) is calculated from the following equation to account for dilution and background levels of each pollutant. ECA = C + D (C – B), when C > B, and ECA = C when C ≤ B, Where, C = the applicable water quality criterion (adjusted for receiving water hardness and expressed as total recoverable metal, if applicable). CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-31 D = the dilution credit (here D = 0, as the Central Coast Water Board has no information with which to justify credit for dilution). B = the background concentration As discussed above, for this Order, dilution was not allowed; therefore: ECA = C For chlorodibromomethane, the applicable water quality criteria are: ECAHuman Health = 0.401 μg/L Step 2: For each ECA based on an aquatic life criterion, the long -term average discharge condition (LTA) is determined by multiplying the ECA times a factor (multiplier), which adjusts the ECA to account for effluent variability. The multiplier varies depending on the coefficient of variation (CV) of the data set and whether it is an acute or chronic criterion/objective. Table 1 of the SIP provides pre-calculated values for the multipliers based on the value of the CV. When the data set contains less than 10 sample results, or 80 percent or more of the data are reported as non -detect (ND), the CV is set equal to 0.6. Derivation of the multipliers is presented in Section 1.4 of the SIP. LTAacute = ECAacute x Multiplieracute 99 LTAchronic= ECAchronic x Multiplierchronic 99 Typically, historic effluent data is used to develop the acute and chronic LTA using equations provided in Section 1.4, Step 3 of the SIP (Table 1 of the SIP also provides this data up to three decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the development of this permit and LTA for acute and chronic were unnecessary to calculate. Step 3: WQBELs, including an AMEL and a MDEL are calculated using the most limiting (the lowest) LTA. The LTA is multiplied times a factor that accounts for averaging periods and exceedance frequencies of the effluent limitations, and for the AMEL, the effluent monitoring frequency. Here, the sampling frequency is set equal to 1 (n = 1). The 99th percentile occurrence probability was used to determine the MDEL multiplier and a 95th percentile occurrence probability was used to determine the AMEL multiplier. Table 2 of the SIP presents the MDEL and AMEL multipliers as a function of the CV. When the data set contains less than 10 sample results, or when 80 percent or more of the data set is reported as non-detect (ND), the CV is set equal to 0.6. Otherwise, the CV is calculated as the standard deviation divided by the mean. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-32 No. of Samples No. of Samples Per Month (n) CV 73 1 0.6 Step 4: Calculate the WQBELs by multiplying the LTA by a factor (multiplier). WQBELs are expressed as AMEL and MDEL. The multiplier is a statistically based factor that adjusts the LTA for the averaging periods and exceedance frequencies of the criteria/objectives and the effluent limitations. The value of the multiplier varies depending on the probability basis, the coefficient of variation (CV) of the data set, the number of samples (for AMEL) and whether it is a monthly or daily limit. Table 2 of the SIP provides pre-calculated values for the multipliers based on the value of the CV and the number of samples. Equations to develop the multipliers in place of using values in the tables are provided in Section 1.4, Step 5 of the SIP and will not be repeated here. AMELaquatic life = LTA x AMELmultiplier 95 MDELaquatic life = LTA x MDELmultiplier 99 AMEL multipliers are based on a 95th percentile occurrence probability, and the MDEL multipliers are based on the 99th percentile occurrence probability. If the number of samples is less than four (4), the default number of samples to be used is four (4). Equations provided in Section 1.4, Step 5 of the SIP are used to develop the AMEL and MDEL for aquatic life using (Table 2 of the SIP also provides this data up to two decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the developmen t of this permit and AMEL and MDEL for aquatic life were unnecessary to calculate. Calculation of human health AMEL and MDEL: Step 5: For the ECA based on human health, set the AMEL equal to the ECAhuman health AMELhuman health = ECAhuman health For chlorodibromomethane: AMELhuman health = 0.401 μg/L Step 6: Calculate the MDEL for human health by multiplying the AMEL by the ratio of the MultiplierMDEL to the MultiplierAMEL. Table 2 of the SIP provides pre-calculated ratios to be used in this calculation based on the CV and the number of samples. MDELhuman health = AMELhuman health x (MultiplierMDEL / MultiplierAMEL) For chlorodibromomethane the following data were used to develop the MDELhuman health: No. of Samples Per Month CV MultiplierMDEL 99 MultiplierAMEL 95 Ratio CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-33 1 0.6 3.11 1.55 2.01 MDELhuman health = 0.401 μg/L x 2.01 = 0.806 μg/L Step 7: Select the lower of the AMEL and MDEL based on aquatic life and human health as the water-quality based effluent limit for the Order. For chlorodibromomethane, the AMELhuman health and MDELhuman health were 0.401 μg/L and 0.806 μg/L respectively. Thus, the human health criteria-based effluent limitations were more stringent and were considered in the Order. 4.3.4.1 Constituents with Reasonable Potential 4.3.4.1.1 Mercury. The RPA used effluent data from December 2014 through December 2022 and showed that there was a reasonable potential for the discharge to exceed the total recoverable mercury criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.012 µg/L and an MDEL of 0.024 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total recoverable mercury. 4.3.4.1.2 Chlorodibromomethane. The previous Order established an AMEL of 0.40 µg/L and an MDEL of 1.0 µg/L for chlorodibromomethane (dibromochloromethane). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chlorodibromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.4 µg/L and an MDEL of 0.81 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chlorodibromomethane. 4.3.4.1.3 Chloroform. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chloroform criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chloroform. 4.3.4.1.4 Dichlorobromomethane. The previous Order established an AMEL of 0.56 µg/L and an MDEL of 1.0 µg/L for dichlorobromomethane. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the dichlorobromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.56 µg/L and an MDEL of 0.96 µg/L have been established in this permit. Effluent and receiving water CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-34 monitoring and reporting requirements have also been established for dichlorobromomethane. 4.3.4.1.5. Methylene Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the methylene chloride criteria; therefore, effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 4.7 µg/L and an MDEL of 9.45 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for methylene chloride. 4.3.4.1.6. Pentachlorophenol. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the pentachlorophenol criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for pentachlorophenol. 4.3.4.1.8. Nitrate and Nitrate + Nitrite. As previously discussed, an effluent limitation for total nitrate (as N) was established through the TMDL for nitrate-nitrogen discharges to San Luis Obispo creek and was retained from the previous permit. Additionally, an effluent limitation for total nitrite (as nitrogen) is established in this order. A separate effluent limitation has not been established for nitrate+nitrite. Nitrate+nitrite is the sum of nitrate and nitrite, and therefore is duplicative of the two established effluent limitations. 4.3.4.1.9. Nitrite. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the total nitrite (as N) criteria, and therefore an effluent limitation is established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 1.0 mg/L has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total nitrite (as N). 4.3.4.1.10. Methylene blue activated substances (MBAS). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the MBAS criteria of 0.2 mg/L from the 2019 Basin Plan. The 0.2 mg/L effluent limitation established in this order is equivalent to the most stringent water quality objective in the 2019 Basin Plan . Effluent and receiving water monitoring and reporting requirements have also been established for MBAS. 4.3.4.1.11 Un-ionized Ammonia. The 2019 Basin Plan includes a water quality objective for un-ionized ammonia (NH3) of 0.025 mg/L. The previous Order did not establish an effluent limitation for un-ionized ammonia. The previous Order incorporated the Basin Plan objective as a receiving water limitation. From December 2014 through April 2020, the Discharger collected 93 concurrent upstream (RSW -004) and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-35 downstream (RSW-005) samples to determine un-ionized ammonia concentrations in the receiving water. The effluent caused the receiving water to exceed the Basin Plan objective on 29 occasions. Reasonable potential was found for un-ionized ammonia, and an effluent limitation and monitoring requirement were established for un -ionized ammonia. The effluent limitation of 0.025 mg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. 4.3.4.1.12. Molybdenum. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the molybdenum criteria of 10 µg/L from the 2019 Basin Plan. An effluent limitation of 10 µg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for molybdenum. 4.3.4.1.13. Total Dissolved Solids. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the total dissolved solids criteria of 650 mg/L in the Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for total dissolved solids. 4.3.4.1.14. Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the chloride criteria of 100 mg/L from the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek . Effluent and receiving water monitoring and reporting requirements have also been established for chloride. 4.3.4.1.15. Sulfate. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sulfate criteria of 100 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sulfate. 4.3.4.1.16. Sodium. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sodium criteria of 50 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sodium. 4.3.4.2 Constituents with No Reasonable Potential As detailed in Table F-8, constituents that were analyzed and received a “No” in the “RPA Result” column did not have a reasonable potential to cause or contribute to an excursion above the 126 U.S. EPA priority toxic pollutants, title 22 MCLs, or any CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-36 numeric water quality objectives included in any State Water Board plans or the 2019 Basin Plan. WQBEL’s are not included in this Order for constituents that do not demonstrate reasonable potential to cause or contribute to an instream excursion of an applicable water quality objective; however monitoring for priority toxic and title 22 pollutants is established in this Order. Most constituents with no reasonable potential are not discussed in this order. This section provides a discussion on the constituent with no reasonable potential for which an effluent limitation has not been retained from the previous order. 4.3.4.2.1 N-nitrosodimethylamine. The previous Order included an AMEL of 0.00069 µg/L and an MDEL of 0.0014 µg/L for n-nitrosodimethylamine. Several sample results analyzed during 2016 showed effluent limitation exceedances. However, in a letter dated February 9, 2017, the Discharger provided additional information to the Central Coast Water Board describing that the cause of the apparent exceedances was due to the test method used to analyze the samples. The Minimum Level (ML) established for n-nitrosodimethylamine in Appendix 4 of the SIP is 5 µg/L for samples analyzed by gas chromatography/ mass spectrometry. The Discharger was using EPA Method 1625M, an “ultra-low-level” method, which is not an approved method in 40 CFR part 136 and is not appropriate for compliance monitoring. The Discharger notified the Central Coast Water Board of its plan to return to using EPA Method 625 to measure n- nitrosodimethylamine in the effluent instead of the “ultra-low-level” the Discharger used in 2016 (i.e., EPA Method 1625M). On May 15, 2017, the Central Coast Water Board provided a written response that concurred with the Discharger regarding the return to EPA Method 625 and that the n-nitrosodimethylamine effluent concentrations reported in 2016 should not have been reported as effluent limitation exceedances because results below the ML of 5 µg/L are not considered violations according to the SIP. The RPA used effluent data from December 2014 through December 2022 that was analyzed using the correct test method and found that there was not reasonable potential for an exceedance of a water quality objective. An effluent limitation of n- nitrosodimethylamine has not been retained for this Order. Additional discussion is included in section 4.4.1 Ant-Backsliding Requirements and section 4.4.1 Antidegradation Policies of this fact sheet. 4.3.5. Whole Effluent Toxicity (WET) Aquatic toxicity is the adverse response of aquatic organisms from exposure to chemical or physical agents, or their synergistic effects in effluent or ambient water. Acute aquatic toxicity refers to adverse response (typically lethality) from a short -term exposure. Chronic aquatic toxicity generally refers to longer exposure duration and measures of both lethal and sub-lethal adverse response. WET testing protects receiving waters from the aggregate toxic effect of a mixture of pollutants that may be present in effluent. The Basin Plan establishes a narrative WQO which states that all waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-37 Survival of aquatic organisms in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge or for another control water. The WE T approach allows for protection of the narrative “no toxics in toxic amounts” criterion while implementing numeric criteria for toxicity. For compliance with the Basin Plan’s narrative toxicity objective and the 2022 Toxicity Provisions, this Order requires the Discharger to conduct WET testing for acute and chronic toxicity in accordance with the Test of Significant Toxicity (TST) statistical approach, as specified in section 5 of the MRP (Attachment E). 4.3.5.1. Test of Significant Toxicity (TST) In 2010, U.S. EPA endorsed the TST statistical hypothesis testing approach, described in the National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, as an improved hypothesis-testing tool to evaluate data from U.S EPA’s toxicity test methods. The TST hypothesis testing approach more reliably identifies toxicity —in relation to the chronic (0.25 or more) and acute (0.20 or more) mean responses of regulatory management concern—than the No Observed Effect Concentration (NOEC) hypothesis-testing approach previously used. On December 1, 2020, the State Water Board adopted Resolution No. 2020 -0044, establishing the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries (ISWEBE Plan), and adopting statewide numeric WQOs for both acute and chronic toxicity and a program of implementation to control toxicity, which are collectively known as the Toxicity Provisions. The Toxicity Provisions, which were revised on October 5, 2021, standardized the regulation of aquatic toxicity for all non- oceanic surface waters.3 U.S. EPA’s Test of Significant Toxicity Design, or TST, approach is an essential component of the Toxicity Provisions as it forms the basis for utilizing numeric WQOs and acts as the primary means of determining compliance with WET effluent limitations. This Order requires application of the TST approach for statistical analysis of WET data. 4.3.5.1.1. Test of Significant Toxicity Design The TST null hypothesis (Ho) for acute toxicity is: “mean discharge IWC response ≤0.80 × mean control response”, where 0.80 is the regulatory management decision (RMD). The TST null hypothesis (Ho) for chronic toxicity is: “mean discharge IWC response ≤0.75 × mean control response”, where 0.75 is the RMD. The null hypotheses for acute and chronic toxicity described in the TST are assigned as numeric WQOs for acute and chronic toxicity in sections II.C.1 and II.C.2 of the Toxicity Provisions. A test result t hat rejects the null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The TST approach is a t -test (formally Student’s t- 3 The Toxicity Provisions were approved by the Office of Administrative Law on April 25, 2022, and by U.S. EPA on May 1, 2023. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-38 test), a statistical analysis comparing two sets of replicate observations —in the case of WET tests, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”)). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month, or in consecutive calendar months, result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be re ported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). Compliance with the toxicity limitation is demonstrated by rejecting the null hypothesis and reporting “Pass”. When the toxicity test results in a “Fail” the Discharger must initiate accelerated monitoring as specified in section 5.3 of the MRP. After accelerated monitoring, if conditions of chronic toxicity are found to persist, the Discharger will be required to conduct a TRE, as described in section 5.4 of the MRP. See section III.B.3 of the Toxicity Provisions for a detailed step-by-step description of the TST statistical method. 4.3.5.2. WET Reasonable Potential Analysis To determine the need for acute and/or chronic toxicity effluent limitations, the Central Coast Water Board conducted a RPA using the TST approach. In conducting the RPA, the Central Coast Water Board considered and evaluated all acute and chronic toxicity data generated during the previous permit term since the data is representative of the actual effluent quality from the Facility. Reasonable potential exists if any of the acute or chronic toxicity tests result in a “Fail” or if the percent effect at the IWC is greater than 10 percent. The IWC for Discharge Point 001 is 100 percent effluent. The Discharger conducted eight acute and 26 chronic toxicity tests using the species Pimephales promelas between October 2015 and October 2022, as shown in Table F - 10 below. Analysis using the TST approach concluded that the Discharger failed zero acute toxicity tests, and 14 chronic toxicity tests, representing a fail rate of 54 percent. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-39 After extensive City staff and consultant review, summarized in the Toxicity Reduction Evaluation Workplan Conclusion report submitted to the Central Coast Regional Water Quality Control Board on May 22, 2019, all Effluent 001 sampling events from October 2016 to October 2018 exhibited at least one of the three qualifying data interpretations of sporadic mortality, suggesting biological interference was the cause of observed toxicity. The Central Coast Water Board reviewed the TRE Workplan and maintained that the failed chronic test results would remain on record. These chronic toxicity test results were used to conclude that the discharge has reasonable potential to cause or contribute to an exceedance of chronic toxicity WQOs and that the discharge is subject to chronic toxicity effluent limitations. In addition, section III.C.5.c. of the Toxicity Provisions requires establishment of chronic toxicity effluent limitations if a POTW is authorized to discharge at a rate equal to or greater than 5.0 MGD and is required to have a pretreatment program by the terms of 40 CFR section 403.8(a). The permitted flow rate for the Facility is 5.4 MGD, and the Discharger is required to have a pretreatment program. Therefore, based on the determination of the RPA, and requirements contained in the Toxicity Provisions, the Order establishes MDEL and MMEL effluent limitations for chronic toxicity. Table F-9. Summary of Acute and Chronic Toxicity Test Results Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 10/6/2015 Pass 2.50 Survival Acute 10/4/2016 Pass 0.00 Survival Acute 10/3/2017 Pass 10.00 Survival Acute 10/30/2018 Pass 0.00 Survival Acute 10/15/2019 Pass 7.50 Survival Acute 10/28/2020 Pass 0.00 Survival Acute 10/5/2021 Pass 0.00 Survival Acute 10/4/2022 Pass 0.00 Survival Acute 10/6/2015 Pass 8.68 Growth Chronic 10/6/2015 Pass 6.78 Survival Chronic 10/4/2016 Pass -13.56 Growth Chronic 10/4/2016 Pass 13.33 Survival Chronic 10/3/2017 Fail 31.69 Growth Chronic 10/3/2017 Fail 40.68 Survival Chronic 10/24/2017 Fail 49.63 Growth Chronic 10/24/2017 Fail 68.33 Survival Chronic 11/28/2017 Pass 17.20 Growth Chronic 11/28/2017 Pass 10.91 Survival Chronic 12/12/2017 Fail 43.78 Growth Chronic 12/12/2017 Fail 58.33 Survival Chronic 8/21/2018 Fail 19.95 Growth Chronic 8/21/2018 Fail 31.67 Survival Chronic 7/31/2018 Pass 14.48 Growth Chronic CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-40 Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 7/31/2018 Fail 34.48 Survival Chronic 10/30/2018 Pass 4.56 Growth Chronic 10/30/2018 Fail 18.33 Survival Chronic 10/15/2019 Pass -12.63 Growth Chronic 10/15/2019 Pass 1.75 Survival Chronic 10/28/2020 Pass -7.95 Growth Chronic 10/28/2020 Pass 0.00 Survival Chronic 10/5/2021 Pass -2.02 Growth Chronic 10/5/2021 Pass 0.00 Survival Chronic 10/4/2022 Pass 3.00 Growth Chronic 10/4/2022 Pass 0.00 Survival Chronic 4.3.5.3. Acute Aquatic Toxicity Although the Discharger reported no acute toxicity test failures from the eight acute toxicity tests conducted during the previous permit term, this permit retains annual effluent monitoring requirements for acute toxicity established in Order No. R3-2014- 0033 due to persistent failure of chronic toxicity tests during the previous permit term, which resulted in a required TRE being conducted. The Order implements federal guidelines (Regions 9 & 10 Guidance for Implementing Whole Effluent Toxicity Testing Programs) by requiring the Discharger to conduct acute species sensitivity testing as described in section 5 of the MRP (Attachment E). This Order requires the Discharger to conduct a screening test using a vertebrate and invertebrate species. After the screening test is completed, the Discharger is required to use the most sensitive species in future acute toxicity testing if the most sensitive species is found not to be Pimephales promelas. 4.3.6. Basin Plan and Bacteria Provisions 4.3.6.1. Bacteria Provisions. The Facility receives domestic wastewater and discharges to surface waters with the water contact recreation beneficial use (REC-1). Because of the nature of domestic wastewater, discharges from publicly owned treatment works with these discharge characteristics have the reasonable potential to cause or contribute to an exceedance of water quality criteria for bacteria. On August 7, 2018, the State Water Board adopted Part 3 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California – Bacteria Provisions and a Water Quality Standards Variance Policy (Bacteria Provisions), which establishes bacteria water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). Under the statewide Bacteria Provisions, the water quality objective protective of the REC-1 beneficial use is, in waters where the salinity is less than one part per thousand (ppth) 95 percent or more of the time: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-41 • The concentration of E. coli shall not exceed 100 colony forming units (cfu) per 100 milliliters (mL) as a six-week rolling geometric mean, calculated weekly. • A statistical threshold value (STV) of 320 cfu/100 mL for E. coli shall not be exceeded by more than 10 percent of the samples collected in a calendar month and calculated in a static manner. Order R3-2014-0033 established effluent limitations for coliform bacteria based on applicable water quality objectives in the Basin Plan for San Luis Obispo Creek. The bacteria water quality objectives in the Bacteria Provisions supersede numeric water quality objectives for bacteria for the REC-1 beneficial use contained in a water quality control plan prior to February 4, 2019. Because San Luis Obispo Creek salinity is less than one part per thousand (ppth) 95 percent or more of the time , this Order establishes E. coli effluent limitations for Discharge Point 001, based on the water quality objectives in the Bacteria Provisions, in place of the previous fecal coliform effluent limitations. 4.3.6.2. Dissolved Oxygen. In order to protect the beneficial uses of San Luis Obispo Creek, Order R3-2014-0033 retained an effluent limit for dissolved oxygen, prohibiting the discharge from containing a dissolved oxygen concentration of less than 4.0 mg/L or so low that it adversely affects beneficial uses. 4.3.6.3. Nitrate. San Luis Obispo Creek is included on the 303(d) List as impaired for nutrients. Central Coast Water Board Resolution R3-2005-0106 established TMDLs for nitrate for discharges to San Luis Obispo Creek. Due to federal and State anti- backsliding regulations, nitrate remains a pollutant of concern for this discharge and the monthly average effluent limitation of 10 mg/L as N is retained from the previous Order. 4.3.6.4. pH. Federal regulations, 40 CFR 133, establish technology-based effluent limitations for pH. The secondary treatment standards require the pH of the effluent to be no lower than 6.0 and no greater than 9.0 standard units. However, the Basin Plan establishes a WQO for pH of between 6.5 to 8.3 standard units for the protection of receiving waters with the beneficial use of Municipal and Domestic Supply (MUN), Agricultural Supply (AGR), and Water Recreation (REC1 and REC2). The Basin Plan establishes a WQO for pH between 7.0 to 8.5 standard units for the beneficial use of Freshwater Habitat (COLD and WARM) and Fish Spawning (SPWN). The previous Order established an effluent limitation of 6.5 to 8.3. However, since San Luis Obispo Creek has MUN, AGR, REC1, REC2, COLD, WARM, and SPWN beneficial uses, a pH effluent limitation of 7.0 to 8.3 is appropriate in order to protect all beneficial uses. This Order updates the previous effluent limitation of 6.5 to 8.3 from the previous Order, based on the water quality objective for the Municipal and Domestic Supply (MUN) beneficial use. For the protection of the COLD beneficial use, this Order applies a receiving water limitation of 7.0 to 8.3, with no change in normal ambient pH levels above 0.5. 4.3.6.5. Oil and Grease. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works has the reasonable potential to cause or contribute to an exceedance of water quality criteria for oil and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-42 grease. The Basin Plan establishes a narrative effluent limitation for oil and grease, which states, “Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. The previous Order contained an AMEL and MDEL of 5.0 mg/L and 10 mg/L, respectively. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.3.6.6. Floating Material. Discharge of treated wastewater through Discharge Point No. 001 shall not contain floating material, including solids, liquids, foams, and scum in concentrations that cause nuisance or adversely affect beneficial uses. This effluent limitation is consistent with the Basin Plan. 4.3.6.7. Settleable Solids. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works have the reasonable potential to cause or contribute to an exceedance of water quality criteria for settleable solids. The Basin Plan establishes a narrative effluent limitation for settleable solids, which states, “Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely aff ects beneficial uses. The previous Order contained an average monthly effluent limitation (AMEL) of 0.1 mL/L. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.4. Final Effluent Limitation Considerations 4.4.1. Anti-Backsliding Requirements Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. 122.44(l) prohibit backsliding in NPDES permits. These anti-backsliding provisions require effluent limitations in a reissued permit to be as stringent as those in the previous permit, with some exceptions where limitations may be relaxed. All effluent limitations in this Order are at least as stringent as the effluent limitations in the previous Order. An effluent limitation for n-nitrosodimethylamine has not been retained from the previous Order because current data analysis shows no reasonable potential. The elimination of this WQBEL is consistent with the exception to the CWA's anti-backsliding requirements expressed at §402 (0)(2)(B)(i) of the Act, which allows a reissued permit to include less stringent limitations when information is available that was not available at the time of permit issuance (other than revised regulations, guidance, or test methods), and that would have justified the application of a less stringent effluent limitation at the time of permit issuance. The removal of the limitation of n- nitrosodimethylamine is based on new data, which was generated during the term of previous Order, and which demonstrates no reasonable potential for discharges from the Facility to cause or contribute to exceedances of applicable WQOs for this pollutant. Therefore, effluent limitations for these pollutants from the previous Order are not retained in this Order. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-43 4.4.2. Antidegradation Policies 40 CFR section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal antidegradation policy. On October 28, 1968, the State Water Board established California’s antidegradation policy when it adopted Resolution Number 68-16, Statement of Policy with Respect to Maintaining the Quality of the Waters of the State. Resolution Number 68-16 requires that existing water quality be maintained unless degradation is justified based on specific findings. The State Water Board has, in State Water Board Order Number 86-17 and an October 7, 1987 guidance memorandum, interpreted Resolution Number 68-16 to be fully consistent with the federal antidegradation policy contained in 40 CFR section 131.12. Similarly, CWA section 303(d)(4)(B) and 40 CFR section 131.12 require that all permitting actions be consistent with the federal antidegradation policy. Together, the state and federal antidegradation policies are designed to ensure that a water body will not be degraded resulting from the permitted discharge. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The renewal of this NPDES permit is consistent with the anti-degradation policy because it is not expected to allow degradation of receiving water quality. No reduction in the existing level of wastewater treatment is anticipated. In addition, the renewal of the NPDES permit will not lower the surface water quality because the conditions in this Order are at least as stringent as the previous permit except for limits described in section 4.4.1 of the Fact Sheet. Specifically, the removal of the final effluent limitation for n-nitrosodimethylamine is consistent with the antidegradation policy because the discharge did not exhibit reasonable potential to exceed the water quality objective, and it is not expected to degrade the water quality of the receiving water. Effluent and receiving water monitoring for this pollutant continue to be required under this Order to ensure effluent and receiving water concentrations do not exceed the objective. 4.4.3. Stringency of Requirements for Individual Pollutants This Order contains both technology-based and water quality-based effluent limitations for individual pollutants. The technology-based effluent limitations consist of restrictions on BOD and TSS. This Order’s technology-based pollutant restrictions implement the minimum applicable federal technology-based requirements. In addition, this Order contains effluent limitations more stringent than the minimum federal technology-based requirements that are necessary to meet water quality standards. For pH, BOD, and TSS both technology-based effluent limitations and water quality-based effluent limitations are applicable. The more stringent of these effluent limitations are implemented by this Order. These limitations are not more stringent than required by the CWA. Water quality-based effluent limitations have been derived to implement water quality objectives that protect beneficial uses. Both the beneficial uses and the water quality objectives have been approved pursuant to federal law and are the applicable federal water quality standards. To the extent that toxic pollutant water CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-44 quality-based effluent limitations were derived from the CTR, the CTR is the applicable standard pursuant to 40 C.F.R. 131.38. The procedures for calculating the individual water quality-based effluent limitations for priority pollutants are based on the CTR implemented by the SIP, which was approved by U.S. EPA on May 18, 2000. Any water quality objectives and beneficial uses submitted to U.S. EPA prior to May 30, 2000, but not approved by U.S. EPA before that date, are nonetheless “applicable water quality standards for purposes of the CWA” pursuant to 40 C.F.R. 131.21(c)(1). Collectively, this Order’s restrictions on individual pollutants are no more stringent than required to implement the requirements of the CWA. 4.4.4. Summary of Final Effluent Limitations 4.4.4.1. Effluent Limitations. The following effluent limitations are applicable to the discharge of disinfected tertiary treated wastewater from the Facility at Discharge Point No. 001. Table F-10. Final Effluent Limitations – Discharge Point EFF-001 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1,351 2,252 - - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - - TSS lbs/day[1] 425 1,351 3,378 - - - - pH[2],[3] standard units - - - 7.0 8.3 - - Oil and Grease mg/L 5 - 10 - - - - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-45 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - - Dissolved Oxygen mg/L - - - 4.0 - - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.01 2 - 0.024 - - - - Chlorodibromom ethane (Dibromochlorom ethane) µg/L 0.40 - 0.81 - - - - Chloroform µg/L 60 - 120.6 - - - - Dichlorobromom ethane µg/L 0.56 - 0.96 - - - - Methylene Chloride µg/L 4.7 - 9.45 - - - - Pentachlorophen ol µg/L 0.28 - 0.56 - - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - - Nitrite, Total mg/L 1 - - - - - - Un-ionized Ammonia mg/L 0.02 5 - - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - - Molybdenum mg/L 0.01 - - - - - - Total Dissolved Solids mg/L - - - - - 650[10] CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-46 [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 6.5-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 6.5-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0-9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 6.5-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Chloride mg/L - - - - - 100[10] Sodium mg/L - - - - - 50[10] Sulfate mg/L -- - - - - 100[10] Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-47 with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 - day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in -stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP -Attachment E). [10] Based on a 12-month running mean. 4.5. Interim Effluent Limitations – Not Applicable 4.6. Land Discharge Specifications – Not Applicable 4.7. Recycling Specifications This Order allows the production and onsite use of disinfected tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements in the State Water Board’s Recycled Water Policy, and those established by DDW at title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. This Order includes water reclamation requirements for the Facility pursuant to the State Water Board’s Division of Drinking Water recommendations submitted to the Central Coast Water Board. This Order requires the Discharger to adhere to the requirements outlined in section 4.3 and any additional conditions pursuant to specifications in updated title 22 engineering reports approved by the State Water Board’s Division of Drinking Water. 4.8. Point of Compliance for Effluent Limitations 4.8.1. The Discharger must comply with the effluent limitations established in this order at location EFF-001. The facility includes a long concrete pipe that sends treated effluent from the facility to San Luis Obispo Creek. In previous permits, the discharge was monitored at the end of the pipe, just before it mixes with San Luis Obispo Creek. Due to safety and cost concerns, the Discharger requested to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-48 perform the majority of their compliance monitoring at the beginning of the pipe. The beginning of the pipe is referred to as EFF-001A and the end of the pipe is referred to as EFF-001B. 5. RATIONALE FOR RECEIVING WATER LIMITATIONS 5.1. Surface Water Receiving water quality is a result of many factors, some unrelated to the discharge. This Order considers these factors and is designed to minimize the influence of the discharge on the receiving water. Specific water quality objectives established by the Basin Plan to meet this goal for all inland surface waters are included as receiving water limitations in section 5.1. of this Order. 6. RATIONALE FOR PROVISIONS 6.1. Standard Provisions Standard Provisions, which apply to all NPDES permits in accordance with 40 C.F.R. section 122.41, and additional conditions applicable to specified categories of permits in accordance with 40 C.F.R. section 122.42, are provided in Attachment D. The Discharger must comply with all standard provisions and with those additional conditions that are applicable under section 122.42. Sections 122.41(a)(1) and (b) through (n) of 40 C.F.R. establish conditions that apply to all state-issued NPDES permits. These conditions must be incorporated into the permits either expressly or by reference. If incorporated by reference, a specific citation to the regulations must be included in the Order. Section 123.25(a)(12) of 40 C.F.R. allows the state to omit or modify conditions to impose more stringent requirements. In accordance with 40 C.F.R. section 123.25, this Order omits federal conditions that address enforcement authority specified in 40 C.F.R. section 122.41(j)(5) and (k)(2) because the enforcement authority under the California Water Code is more stringent. In lieu of these conditions, this Order incorporates by reference California Water Code section 13387(e). 6.2. Special Provisions 6.2.1. Reopener Provisions The Order may be modified in accordance with the requirements set forth at 40 C.F.R. parts 122 and 124, to include appropriate conditions or limits based on newly available information, or to implement any, new state water quality objectives that are approved by the U.S. EPA. As effluent is further characterized through additional monitoring, and if a need for additional effluent limitations becomes apparent after additional effluent characterization, the Order will be reopened to incorporate such limitations. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential to cause, or contributes to an excursion above a SIP water quality objective. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-49 6.2.2. Special Studies and Additional Monitoring Requirements 6.2.2.1. Whole Effluent Toxicity. The Basin Plan states, “All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board.” The Basin Plan further states, “Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality condition, shall not be less than that for the same waterbody in areas unaffected by the waste discharge…” and that effluent limitations based upon acute bioassays of effluent will be prescribed where appropriate. This permit establishes acute and chronic monitoring requirements, and chronic toxicity effluent limitations in accordance with the 2022 Toxicity Provisions, which incorporates the narrative objectives of the Basin Plan. The Order and MRP require the Discharger to conduct accelerated toxicity testing for exceedances of the acute toxicity WQOs, as described in the Toxicity Provisions, and/or chronic toxicity effluent limitations. If the accelerated testing demonstrates toxicity, the Discharger is required to submit a TRE Work Plan in accordance with U.S. EPA guidance, which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharge will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TIE process in accordance with the Work Plan if the results of toxicity testing exceed the effluent limitation or trigger for toxicity. 6.2.3. Best Management Practices and Pollution Prevention 6.2.3.1. Pollutant Minimization Program. The Discharger is required to minimize the discharge of pollutants consistent with the requirements of section 2.4.5.1 of the SIP. The goal of the Pollutant Minimization Program is to reduce all potential sources of a priority pollutant through pollutant minimization strategies to maintain the effluent concentration at or below water quality -based effluent limitations. 6.2.3.2. Salt and Nutrient Management Program. Section VI.C.3 of the previous Order required the Discharger to conduct a Salt Management Study to control levels of TDS, chloride, sodium, sulfate, and boron (collectively referred to as salts) in discharges from the Facility and attain applicable WQOs for salts in the San Luis Obispo Creek sub-basin of the Estero Bay Drainage Basin. Data from the term of the previous Order indicated the Facility has reasonable potential to cause or contribute to downstream impairment for salts loading. Therefore, in addition to effluent and receiving water monitoring for TDS, chloride, sulfate, boron and sodium, this Order requires the Discharger to continue to update and implement the Salt Management Program and provide CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-50 annual reports. Additionally, the Discharger shall develop and implement a Nutrient Management Program as part of the Salt and Nutrient Management Program, as discussed in section 6.3.3.1. of this Order, based on the Recycled Water Policy discussed in section 3.5.3. of this Fact Sheet. 6.2.4. Construction, Operation, and Maintenance Specifications 6.2.4.1 The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.2.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.2.5.1. Pretreatment. This Order contains pretreatment requirements consistent with applicable effluent limitations, national standards of performance, and toxic and performance effluent standards established pursuant to sections 208(b), 301, 302, 303(d), 304, 306, 307, 403, 404, 405, and 501 of the CWA, and amendments thereto. This permit contains requirements for the implementation of an effective pretreatment program pursuant to section 307 of the CWA; 40 CFR 35 and 403; and/or Title 23, CCR section 2233. 6.2.5.2. Collection System. The State Water Board issued General Waste Discharge Requirements for Sanitary Sewer Systems, Water Quality Order 2022-0103- DWQ (General Order) on December 6, 2022. The General Order requires public agencies that own or operate sanitary sewer systems with sewer lines one mile of pipe or greater to enroll for coverage and comply with the General Order. The General Order requires agencies to develop sanitary sewer management plans and report all sanitary sewer overflows, among othe r requirements and prohibitions. The General Order contains requirements for operation and maintenance of collection systems and for reporting and mitigating sanitary sewer overflows that are more extensive, and therefore, more stringent than the requirements under federal standard provisions. The Discharger obtained enrollment for regulation under the General Order 2022-0103-DWQ. 6.2.5.3. Resource Recovery from Anaerobically Digestible Material. Some POTWs choose to accept organic material such as food waste, fats, oils, and grease into their anaerobic digesters for co-digestion to increase production of methane and other biogases for energy production and to prevent such materials from being discharged into the collection system, which could cause sanitary sewer overflows. The California Department of Resources Recycling and Recovery has proposed an exemption from requiring Process Facility/Transfer Station permits where this activity is regulated under waste discharge requirements or NPDES permits. The proposed exemption is restricted to anaerobically digestible material that has been prescreened, slurried, and processed/conveyed in a closed system to be co-digested with regular POTW sludge. The proposed exemption requires that a POTW develop standard operating procedures for the proper handling, processing, tracking, and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-51 management of the anaerobically digestible material before it is received by the POTW. Standard operating procedures are required for POTWs that accept hauled food waste, fats, oil, and grease for injection into anaerobic digesters. The development and implementation of standard operating procedures for management of these materials is intended to allow the California Department of Resources Recycling and Recovery to exempt this activity from separate and redundant permitting programs. If the POTW does not accept food waste, fats, oil, or grease for resource recovery purposes, it is not required to develop and implement standard operating procedures. 6.2.5.4. Biosolids. Provisions regarding sludge handling and disposal ensure that such activities will comply with all applicable regulations. 40 C.F.R. part 503 sets forth U.S. EPA’s final rule for the use and disposal of biosolids, or sewage sludge, and governs the final use or disposal of biosolids. The intent of this federal program is to ensure that sewage sludge is used or disposed of in a way that protects both human health and the environment. U.S. EPA’s regulations require that producers of sewage sludge meet certain reporting, handling, and disposal requirements. As the U.S. EPA has not delegated the authority to implement the sludge program to the State of California, the enforcement of sludge requirements that apply to the Discharger remains under U.S. EPA's jurisdiction at this time. U.S. EPA, not the Central Coast Water Board, will oversee compliance with 40 C.F.R. part 503. 6.2.5.5. Discharges of Stormwater. Discharges of stormwater from POTWs with a design capacity greater than 1.0 MGD are applicable for coverage under General State Water Board Order No. 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Dischargers of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.2.6. Other Special Provisions 6.2.6.1. Recycled Water Policy Salt/Nutrient Management Plan. This Order requires the Discharger to develop and implement a Salt/Nutrient Management Plan. This requirement is based on the Recycled Water Policy. 6.2.6.2. Climate Change Adaptation Program. On March 7, 2017, the State Water Board adopted a resolution in recognition of the challenges posed by climate change that requires a proactive approach to climate change in all State Water Board actions, including drinking water regulation, water quality protection, and financial assistance (Resolution 2017- 0012). The resolution lays the foundation for a response to climate change that is integrated into all State Water Board actions, by giving direction to the State Water Board divisions and encouraging coordination with the regional water quality control boards. This Order requires the Discharger to implement and submit a Climate Change Adaptation Program. The Central Coast Water Board is addressing the threats of climate change and flooding by including provisions CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-52 in new and reissued orders that ensure climate change mitigation and adaptation strategies are implemented. There is widespread scientific consensus that climate change is occurring and will continue at an accelerating rate into the future. Extreme weather events, including drought, high-intensity precipitation, flooding, and extreme heat have occurred through much of California in recent years and are projected to increase in frequency, extent, or intensity due to climate change. Climate change has the potential to impact discharging facilities through inundation, storm impacts, and erosion, increasing the risk of accidental discharge that results in discharge permit violations. These events have significant implications for wastewater treatment and operations, such as increased corrosion, deposition of solids, infiltration, overflows, inundation of facilities, impairment of treatment processes, and disruption of power or electrical components. Due to the long-term nature of these risks, there is a need to avoid piecemeal or reactionary adaptation and instead undertake proactive, long-term planning with consideration of various adaptation strategies that both keep facilities safe, maintain safe discharging practices, and avoid impacts to resources. A description of the actions taken by the Discharger are described in section 2.5 – Response to Climate Change of this Order. These requirements are consistent with 40 CFR section 122.41(e), requiring permittees to ensure compliance through proper operation and maintenance of facilities, including installation and operation of appropriate auxiliary and backup facilities, and they are authorized pursuant to Water Code section 13383. (In re the City of Oceanside, Fallbrook Public Utilities Dist. And the Southern California Alliance of Publicly Owned Treatment Works, State Water Board Order WQ 2021- 0005, February 12, 2021 at p. 26.) The Los Angeles Water Board understands that the cost of preparing such a plan could be significant (estimated cost range of $25,000-$60,000), but "the costs of ensuring resilient infrastructure to protect water quality against the effects of climate change is warranted." (Fallbrook, at p. 27.) 6.2.7. Compliance Schedules – Not Applicable 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS CWA section 308 and 40 C.F.R. sections 122.41(h), (j)-(l), 122.44(i), and 122.48 require that all NPDES permits specify monitoring and reporting requirements. Sections 13267 and 13383 of the California Water Code also authorize the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements related to discharges to navigable waters or publicly owned treatment works, with section 13267 being the specific statute authorizing all such activities pertaining to the State Water Board’s Water Quality Control Policy for Recycled Water. The MRP, Attachment E of this Order, establishes monitoring, reporting, and recordkeeping requirements that implement federal and state requirements. The following provides the rationale for the inclusion of the monitoring and reporting requirements contained in the MRP for this facility to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-53 ensure compliance with Order requirements to ensure protection of water quality and beneficial uses. The Central Coast Water Board has considered the cost and need for monitoring and reporting generally in this NPDES permit. The discharger has provided the Central Coast Water Board with an estimation of its monitoring and reporting costs here, which are $226,860 for five years. Although the costs are significant, the costs are reasonable considering the nature of the wastewater discharge and because they result in critical data required under the Clean Water Act and which are needed to evaluate water quality generally, the impacts of the discharges on human and aquatic and benthic health, and water quality specifically, and to ensure that beneficial uses are protected. The requirements are generally comparable to other inland dischargers in the region. 7.1. Influent Monitoring In addition to influent flow monitoring, monitoring for BOD 5 and TSS is required to determine compliance with the Order’s percent removal requirement for these pollutants and to assess plant performance. Influent monitoring requirements have been retained from the previous Order. 7.2. Effluent Monitoring Effluent monitoring is necessary to determine compliance with effluent limitations and evaluate compliance with applicable water quality objectives and criteria. Effluent monitoring requirements have been retained from the previous Order for Discharge Point 001, with some exceptions. Effluent monitoring for fecal coliform has been removed and replaced with E. coli monitoring to be consistent with the updated Bacteria Provisions. Effluent monitoring frequency has been increased in this Order to monthly for those pollutants with a reasonable potential to cause or contribute to an exceedance of a water quality standards and for which effluent limitations were established: mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, nitrite (as N), un- ionized ammonia, MBAS, total dissolved solids, sulfate, chloride, and sodium. Chronic toxicity monitoring has increased to monthly to reflect the requirements of the updated Toxicity Provisions. A quarterly effluent monitoring requirement has been established for hardness to assist with the next permit’s reasonable potential analysis. An annual effluent monitoring frequency has been established for results of the reasonable potential analysis and the 2019 Basin Plan objectives . 7.3. Whole Effluent Toxicity Testing Requirements Acute and chronic toxicity monitoring requirements and chronic toxicity effluent limitations have been established in this Order in accordance with the 2020 Toxicity Provisions in the ISWEBE Plan. An acute toxicity test is conducted over a short time period and measures mortality. A chronic toxicity test is conducted over a longer period of time and may measure mortality, reproduction, and growth. For this permit, chronic toxicity in the discharge was evaluated using U.S. EPA’s 2010 TST hypothesis testing approach and is expressed as “Pass” or “Fail” for the median CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-54 monthly summary results and “Pass” or “Fail” and “Percent Effect” for each individual acute and chronic toxicity result. The chronic toxicity effluent limitations protect the narrative WQO in the Basin Plan and comply with the requirement in the Toxicity Provisions to establish chronic effluent limitations for Facilities with permitted discharges greater than 5.0 MGD and a pretreatment program. This Order requires the Discharger to submit an updated TRE Work Plan submitted pursuant to Order No. R3-2014-0033 within 90 days of the effective date of the Order. The TRE Work Plan must describe steps the Discharger intends to follow if the effluent limitation for chronic toxicity is exceeded. If a routine acute and/or chronic toxicity test results in a “Fail” at the IWC, this Order requires the Discharger to conduct accelerated monitoring to determine the cause of the toxicity. A TRE is required when the Discharger has any combination of two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. In addition, if other information indicates toxicity (e.g., results of additional monitoring, fish kills, intermittent recurring toxicity, etc.), then the Central Coast Water Board may require a TRE. If a TRE is required, the Discharger is required to submit a detailed TRE Work Plan in accordance with U.S. EPA guidance which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharger will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TRE/TlE process in accordance with the submitted work plan if the results of toxicity testing exceed the effluent limitations for chronic toxicity. This Order retains annual acute toxicity monitoring requirements and establishes monthly chronic toxicity monitoring requirements based on the RPA determination for toxicity using the TST approach and the Toxicity Provisions. Refer to section 5 of the MRP (Attachment E). 7.4. Recycled Water Monitoring Recycled water monitoring is necessary to evaluate compliance with recycling specifications detailed in section 4.3 of this Order. 7.5. Receiving Water Monitoring 7.5.1. Surface Water Surface water receiving water requirements are necessary to evaluate compliance with water quality objectives, WQBELs, and the protection of beneficial uses. Surface water monitoring requirements have been retained from Order R3-2014-0033 for Discharge Point 001, with some changes in sampling frequency and additional constituents to monitor. Annual monitoring for CTR and title 22 pollutants has been included in this Order because it had not been required historically and is necessary to obtain the background (B) concentration data that will be used for the next permit’s reasonable potential analysis. Quarterly sampling of E.coli has been included in this Order to be consistent with CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-55 the statewide Bacteria Provisions. Sampling frequency for flow, turbidity, color, pH, dissolved oxygen, and temperature have been decreased from weekly to monthly due to personnel safety concerns at sampling locations in the creek. Monthly monitoring of these parameters will provide sufficient data of the receiving water. Quarterly monitoring of boron and monthly monitoring of TDS, chloride, sodium, and sulfate have been included in this Order to provide an understanding of salts concentrations in the receiving water. The addition of quarterly monitoring of hardness in this Order will assist with the next permit’s reasonable potential analysis. 7.5.2. Groundwater Consistent with the previous permit, groundwater monitoring requirements have not been included. 7.6. Other Monitoring Requirements 7.6.1. Discharge Monitoring Report-Quality Assurance (DMR-QA) Study Program Under the authority of section 308 of the CWA (33 U.S.C. 1318), U.S. EPA requires major and selected minor dischargers under the NPDES Program to participate in the annual DMR-QA Study Program. The DMR-QA Study Program evaluates the analytical ability of laboratories that routinely perform or support self-monitoring analyses required by NPDES permits. There are two options to satisfy the requirements of the DMR-QA Study Program: (1) The Discharger can obtain and analyze a DMR-QA sample as part of the DMR-QA Study; or (2) Per the waiver issued by U.S. EPA to the State Water Board, the Discharger can submit the results of the most recent Water Pollution Performance Evaluation Study from its own laboratories or its contract laboratories. A Water Pollution Performance Evaluation Study is similar to the DMR-QA Study. Thus, it also evaluates a laboratory’s ability to analyze wastewater samples to produce quality data that ensure the integrity of the NPDES Program. The Discharger shall ensure that the results of the DMR-QA Study or the results of the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board. The State Water Board’s Quality Assurance Program Officer will send the DMR-QA Study results or the results of the most recent Water Pollution Performance Evaluation Study to U.S. EPA’s DMR-QA Coordinator and Quality Assurance Manager. 7.6.2. Annual Volumetric Reporting of Wastewater and Recycled Water To establish a realistic estimate of statewide recycled water use and potential for increased recycled water use statewide, the Recycled Water Policy requires Dischargers to report the volume of treated wastewater and recycled water. The annual report will meet implementation needs of the Recycled Water Policy and fill data gaps for additional statewide water planning efforts. The burden and cost of preparing the report is reasonable and consistent with the interest of the state in maintaining water quality and developing alternative water supplies to increase water resiliency. The Discharger shall ensure that all volumetric reporting requirements from this Order are submitted in electronic format via the State CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-56 Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. The State Water Board will evaluate progress towards the recycled water goals in the Recycled Water Policy and evaluate the need to update the recycled water goals in the future based on consistent statewide data. 7.6.3. Biosolids/Sludge Monitoring Biosolids monitoring shall be reported in the annual report in accordance with 40 C.F.R. 503. Biosolids monitoring requirements have been retained from the previous Order. 7.6.4. Pretreatment Monitoring Pretreatment monitoring shall be reported in the annual report in accordance with requirements in 40 C.F.R. 403.8. Pretreatment monitoring requirements have been retained from the previous Order. 7.6.5. Salt and Nutrient Management Plan Reporting Salt and Nutrient Management Plan reporting requirements have been retained in this Order to help identify and reduce salt and nutrient loading in effluent. This salt/nutrient management report shall be included as a separate report from the annual report. 7.6.6. Discharge to Evaporation Ponds Reports of discharge to and from the Facility’s evaporation ponds are required pursuant to California Water Code section 13383. Any costs incurred with this reporting are expected to be minimal. The reporting is necessary to ensure compliance with the provisions of this Order, inform follow-up actions in the event of noncompliance with the provisions of this Order, and to protect human health and water quality. 8. CONSIDERATION OF NEED TO PREVENT NUISANCE AND WATER CODE SECTION 13241 FACTORS The requirements set forth in subsections 2.4 and 4.3 of this Order are included to implement state law only. These requirements are not required or authorized under the federal CWA; consequently, violations of these requirements are not subject to the enforcement remedies that are available for NPDES violations. As required by Water Code section 13263, the Central Coast Water Board has considered the need to prevent nuisance and the factors listed in Water Code section 13241 in establishing the state law provisions/requirements. The Central Coast Water Board finds, on balance, that the state law requirements in this Order are reasonably necessary to prevent nuisance and to protect beneficial uses identified in the Basin Plan, and the section 13241 factors are not sufficient to justify failing to protect those beneficial uses. 8.1. Need to prevent pollution or nuisance In establishing effluent limitations in this Order, the Central Coast Water Board has considered state law requirements to prevent pollution or nuisance as defined in CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-57 section 13050, subdivisions (l) and (m), of the Water Code. The requirements in this Order, including those set forth in subsections 2.4 and 4.3, will prevent pollution and nuisance. 8.2. Past, present, and probable future beneficial uses of water Chapter 2 of the Basin Plan identifies designated beneficial uses for water bodies in the Central Coast Region. Beneficial uses of water relevant to this Order are also identified above in sections 3.3.1 of this Fact Sheet. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order, including those set forth in sections 2.4 and 4.3 of this Order. Accordingly, the requirements herein protect and augment the past, present and probable future beneficial uses of the water. 8.3. Environmental characteristics of the hydrographic unit under consideration, including the quality of water available thereto The environmental characteristics of this watershed are discussed in the Basin Plan, as well as available in State of the Watershed reports and the State’s CWA Section 303(d) List of impaired waters. The environmental characteristics of the hydrographic unit, including the quality of available recycled water that may be produced as a result of this Order will be improved by compliance with the requirements of this Order. 8.4. Water quality conditions that could reasonably be achieved through the coordinated control of all factors which affect water quality in the area The water quality standards necessary to protect beneficial uses of San Luis Obispo Creek Sub-Basin of the Estero Bay Drainage Basin can reasonably be achieved through the coordinated control of all factors that affect water quality in the area, including the conservation of water and/or the production of recycled water authorized by this Order. For example, the water quality in the watershed and/or groundwater basin could be improved through the addition or use of recycled water authorized by this Order, which meets title 22 standards. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order. 8.5 Economic Considerations The Permittee presented evidence regarding cost of monitoring but did not present additional evidence concerning other economic considerations related to this Order, such as the benefits of producing recycled water and benefits resulting from protection of beneficial uses of San Luis Obispo Creek. The Central Coast Water Board has considered the economic impact of requiring certain provisions pursuant to state law, including the costs of conducting feasibility studies for recycling, conservation, and climate change. Any additional costs associated with producing any study are reasonably necessary to prevent nuisance and protect beneficial uses identified in the Basin Plan and to improve the water supply resiliency. The failure to consider conservation or recycled water could result in the loss of, or impacts to, beneficial uses, which would have a detrimental economic impact, particularly given the effects on beneficial uses and supplies of water from the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-58 drought and climate change. Economic considerations related to costs of compliance are therefore not sufficient, in the Central Coast Water Board’s determination, to justify failing to prevent nuisance and protect beneficial uses. 8.6 The need for developing housing within the region The Central Coast Water Board does not anticipate that these state law requirements will adversely impact the need for housing in the area. To the contrary, this Order helps address the need for housing by controlling pollutants in discharges and by allowing the reuse and exportation of recycled water for use in the area. Both of these things will improve the quality of local surface and groundwater, as well as water supply generally. This may in turn increase the region’s capacity to support continued housing development. Therefore, the potential for developing housing in the area will be facilitated by the conservation of water, or reuse or the production of recycled water, under this permit. 8.7. Need to develop and use recycled water The State Water Board’s Recycled Water Policy requires the Central Coast Water Board to encourage the use of recycled water. In addition, as discussed immediately above, a need to develop and use recycled water exists within the region, especially during times of drought. To encourage recycling, the Permittee is required by this Order to continue to explore the feasibility of recycling to maximize the beneficial reuse of tertiary treated effluent and to report on its recycled water production and use. The Discharger shall submit an update to this feasibility investigation as part of the submittal of the Report of Waste Discharge (ROWD) for the next permit renewal. 9. PUBLIC PARTICIPATION The Central Coast Water Board is considering the issuance of WDRs that will serve as an NPDES permit for the City of San Luis Obispo Water Resource Recovery Facility. As a step in the WDR adoption process, Central Coast Water Board staff developed tentative WDRs and encourages public participation in the WDR adoption process. 9.1. Notification of Interested Persons The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provid ed an opportunity to submit written comments and recommendations. Notification was provided via the Central Coast Water Board’s website and e-mail subscription service. The public can access the agenda and any changes in dates and locations through the Central Coast Water Board’s website at http://www.waterboards.ca.gov/centralcoast/ CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-59 9.2. Written Comments Interested persons were invited to submit written comments on December 14, 2023, concerning these tentative WDRs. To be fully responded to by staff and considered by the Central Coast Water Board, the written comments were due at the Central Coast Water Board office by 5:00 p.m. on January 16, 2024. 9.3. Public Hearing The Central Coast Water Board held a public hearing on the tentative WDRs during its regular Board meeting on the following date and time and at the following location: Date: June 20-21, 2024 Time: 9:00 am-5:00 pm Location: Link to video and teleconference were provided at https://www.waterboards.ca.gov/centralcoast/board_info/age ndas/2024/2024_agendas.html Interested persons were invited to attend. At the public hearing, the Central Coast Water Board heard testimony pertinent to the discharge, WDRs, and permit. For accuracy of the record, important testimony was requested in writing. 9.4. Reconsideration of Waste Discharge Requirements Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Board must receive the petition by 5:00 p.m., within 30 calendar days of the date of adoption of this Order at the following address, except that if the thirtieth day following the date of this Order falls on a Saturday, Sunday, or state holiday, the petition must be received by the State Water Board by 5:00 p.m. on the next business day: State Water Resources Control Board Office of Chief Counsel P.O. Box 100, 1001 I Street Sacramento, CA 95812-0100 Or by email at waterqualitypetitions@waterboards.ca.gov For instructions on how to file a petition for review, see the State Water Board’s website on instructions for filing water quality petitions at: https://www.waterboards.ca.gov/public_notices/petitions/water_quality/wqpetition_i nstr.shtml. 9.5. Information and Copying The Report of Waste Discharge, other supporting documents, and comments received are on file and may be inspected at the address above at any time CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-60 between 8:00 a.m. and 5:00 p.m., Monday through Friday. Copying of documents may be arranged through the Central Coast Water Board by calling (805) 549- 3147. 9.6. Register of Interested Persons Any person interested in being placed on the mailing list for information regarding the WDRs and NPDES permit should contact the Central Coast Water Board, reference this facility, and provide a name, address, and phone number. 9.7. Additional Information Requests for additional information or questions regarding this order should be directed to Sarah Crable at (805) 549-3706 or Sarah.Crable@waterboards.ca.gov or Arwen Wyatt-Mair at (805) 542-4695 or Arwen.Wyattmair@waterboards.ca.gov. 33 From:Anderson, Matt Sent:Wednesday, October 1, 2025 8:38 AM To:Brant Jorgenson Subject:RE: Toxicity Update and Map Attachments:Order R3-2024-0001 (2).pdf Brant, Can we dig into the MDEL potential violation? I am still trying to figure out the nuances of this permit and the TST, thank you in advance for your guidance. Even though we had the fail result, we did not trigger the MDEL for the Cerio, due to the bullet point 8 listed below – which specifically lists the 50 percent or greater effect on survivability. But do to the single fail, if we reported and accepted the results, we would need to sample two more times (and pass) to achieve MMEL compliance. Chris and I are meeting at 9:30 this morning, I will email John before noon on our next steps. Matt 34 35 From: Brant Jorgenson <bjorgenson@pacificecorisk.com> Sent: Tuesday, September 30, 2025 4:04 PM To: Anderson, Matt <manderso@slocity.org>; John Richard <jrichard@pacificecorisk.com> Subject: Re: Toxicity Update and Map MaƩ Thanks for this. One point of clarificaƟon is that if the Cerio test were accepted, it would not trigger an MDEL viola Ɵon as there wasn’t a >50% effect to survival in that test. This would related to your bullet 3 below. Will wait to hear from you which route you would like to go. We won’t work on the report un Ɵl we know the direcƟon you plan on taking. Thanks. Brant Jorgenson, PhD Vice President/Special Projects Director Pacific EcoRisk 2250 Cordelia Road Fairfield, CA 94534 P: (707) 207-7760 P: (707) 207-7779 (Direct) C: (707) 639-6800 http://www.pacificecorisk.com Confidentiality Notice: This e-mail and document(s) accompanying this e-mail contain confidential information that is legally privileged. The information is intended only for the use of the intended recipient(s) named above. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution, or the taking of any action in reliance on the contents of this e-mail and its attachments, except its direct delivery to the intended recipient(s) named above, is strictly prohibited. If you have received this e-mail in error, please notify us immediately by telephone. Pacific EcoRisk is committed to providing professional quality services to its clients. As part of an ongoing improvement process, we would appreciate your feedback on our performance. Please click on the link below to complete a short survey. Click here From: "Anderson, Matt" <manderso@slocity.org> Date: Tuesday, September 30, 2025 at 3:59 PM To: John Richard <jrichard@pacificecorisk.com> Cc: Brant Jorgenson <bjorgenson@pacificecorisk.com> Subject: FW: Toxicity Update and Map John, I don’t have confirmation from Chris Lehman, but here was what we have tentatively put together at this time. I’ll keep you posted as I receive direction. Matt From: Anderson, Matt Sent: Tuesday, September 30, 2025 1:57 PM To: Lehman, Chris <clehman@slocity.org> 36 Cc: McGrath, Patrick <pmcgrath@slocity.org> Subject: Toxicity Update and Map Chris, Bad news – We had a shipping issue, the Saturday delivery didn’t show up until Monday. And, the Cerio daphnia (water flea) failed. The Green alga results were not impacted from the shipping issue. Here are the options: 1. Patrick and I approve this one but want your feedback – We would accept the results for the Fathead Minnow, report it with the monthly and invalidate the remainder of the sensitivity screening due to not achieving or following the routine testing procedure. Tyler and I would address this in the cover letter. We would resume the quarterly sensitivity screening in November. 2. We could invalidate the whole report/test, and report the result as insufficient monitoring. Brant has sent a follow-up email stating that we could go with the “toxicity provisions have a framework for a “replacement test”. “ We would have no result for September and identify the October sample as being the replacement. 3. We report all results from this screening resulting in a MDEL violation. We would need to begin accelerated monitoring for the Cerio daphnia, 2 more events for MMEL compliance. The scheduled listed below would be shortened to end in April 2026. We would risk one violation for September 2025 and would potentially set us up for Cerio daphnia becoming our most sensitive species, not our most desirable outcome. Long Term 1. Once we receive the final report from PER, we notify Sarah of the ‘failed’ screening with the updated schedule. The updated schedule will deviate from the Chronic Sensitivity Screening requirements outlined in Attachment E 5.2.7. We will miss the completion of the sensitivity screening in the prescribed 18 month period, but will ensure that our sensitivity screening is conducted during four consecutive quarters. a. Continuing with routine monitoring in October at Eff-001 B, Fathead Minnow only. b. Resume sensitivity screening in November. We will treat this sample as event 1, in quarter 1, and start the clock on “four sensitivity screening. With this test, we will request the Green Alga to be continuously mixed on the shaker fand for the Cerio daphnia to be run in duplicate with additional dilutions. This will cost some extra money, but it should lessen the potential for another failed test. c. December – routine monitoring with the Fathead Minnow d. January – Quarter 2 of the sensitivity screening. See the notes from b. e. February - routine monitoring with the Fathead Minnow f. April - Quarter 3 of the sensitivity screening. See the notes from b. g. May - routine monitoring with the Fathead Minnow h. June - routine monitoring with the Fathead Minnow i. July - Quarter 4 of the sensitivity screening. See the notes from b. Matt Anderson Laboratory Manager Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications 37 From:Anderson, Matt Sent:Thursday, September 4, 2025 2:30 PM To:Crable, Sarah@Waterboards Cc:Lehman, Chris; McGrath, Patrick; Parsons, Patrice; Chen, Bryan; Duncan, Tanner; Rose, Jill Subject:Change in Effluent Monitoring and Reporting and Toxicity Sensitivity Screening Update Attachments:Order R3-2024-0001 (1).pdf; EFF-001 Export 24-25.xlsx Good afternoon Sarah, I hope all is well this Tuesday. Per Order R3-2024-0001, Attachment E, page E-8, “If no exceedances of the effluent limitation occur for a minimum of 12 consecutive months of monitoring then the frequency of monitoring shall be reduced to quarterly. Subsequently, if an exceedance of the effluent limitation occurs during quarterly monitoring, the monitoring frequency shall return to monthly. The Discharger must notify the Central Coast Water Board of the change in monitoring frequency.” The City of San Luis Obispo’s Water Resource Recovery facility has had 12 consecutive months of compliance and has not exceeded effluent limits for MBAS, methylene chloride, chloroform, and pentachlorophenol. We will adjust our monitoring schedule this month, and will resume sampling MBAS, methylene chloride, chloroform, and pentachlorophenol on a quarterly basis beginning October 2025. The Water Resource Recovery Facility will resume toxicity sensitivity screening on Wednesday 9/17/2025. Please call or email me with any questions. 38 Matt Anderson Laboratory Manager Public Utilities 39 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101, San Luis Obispo, California 93401 Phone (805) 549-3147 Fax (805) 543-0397 Central Coast Regional Water Quality Control Board (http://www.waterboards.ca.gov/centralcoast) ORDER R3-2024-0001 NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT NUMBER CA0049224 WASTE DISCHARGE REQUIREMENTS FOR THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY The following Discharger is subject to waste discharge requirements set forth in this Order: Discharger City of San Luis Obispo Name of Facility Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Table 1. Discharge Location Discharge Point Effluent Description Discharge Point Latitude (North) Discharge Point Longitude (West) Receiving Water 001 Tertiary treated domestic wastewater 35.244307° 120.680618° San Luis Obispo Creek 002 Disinfected Tertiary Recycled Municipal Wastewater - - Reclamation Use This Order was adopted on: June 20, 2024 This Order shall become effective on: September 1, 2024 This Order shall expire on: August 31, 2029 The Discharger shall file a Report of Waste Discharge as an application for reissuance of waste discharge requirements in accordance with title 23, California Code of Regulations and an application for reissuance of a National Pollutant Discharge CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 2 Elimination System permit no later than 180 days prior to the Order expiration date. The U.S. Environmental Protection Agency and the California Regional Water Quality Control Board, Central Coast Region have classified this discharge as follows: Major discharge. I, Ryan E. Lodge, Executive Officer, do hereby certify that this Order with all attachments is a full, true, and correct copy of an order adopted by the California Regional Water Quality Control Board, Central Coast Region on the date indicated above. Ryan E. Lodge, Executive Officer CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 3 TABLE OF CONTENTS 1. FACILITY INFORMATION .......................................................................................... 4 2. FINDINGS ................................................................................................................... 4 3. DISCHARGE PROHIBITIONS .................................................................................... 7 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS ................................. 7 4.1. Effluent Limitations – Discharge Point 001 ........................................................ 7 4.2. Land Discharge Specifications – Not Applicable ............................................. 11 4.3. Recycling Specifications – Discharge Point 002 ............................................. 11 5. RECEIVING WATER LIMITATIONS ......................................................................... 12 5.1. Surface Water Limitations ............................................................................... 12 5.2. Groundwater Limitations ................................................................................. 16 6. PROVISIONS ............................................................................................................ 17 6.1. Standard Provisions ........................................................................................ 17 6.2. Monitoring and Reporting Program (MRP) Requirements ............................... 17 6.3. Special Provisions ........................................................................................... 17 7. COMPLIANCE DETERMINATION ............................................................................ 23 TABLE OF TABLES Table 1. Discharge Location ............................................................................................ 1 Table 2. Effluent Limitations at Discharge Point 001 ....................................................... 8 Table 3. Organic Substances Water Quality Criteria ..................................................... 14 Table 4. Hardness Dependent Metals Criteria .............................................................. 15 Table 5. Annual Mean Surface Water Quality Objectives .............................................. 15 Table 6. Groundwater Objectives .................................................................................. 17 TABLE OF ATTACHMENTS ATTACHMENT A – DEFINITIONS ...............................................................................A-1 ATTACHMENT B – MAP ..............................................................................................B-1 ATTACHMENT C – FLOW SCHEMATIC .................................................................... C-1 ATTACHMENT D – STANDARD PROVISIONS ......................................................... D-1 ATTACHMENT E – MONITORING AND REPORTING PROGRAM ............................E-1 ATTACHMENT F – FACT SHEET ............................................................................... F-1 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 4 1. FACILITY INFORMATION Information describing the City of San Luis Obispo (Discharger) Water Resource Recovery Facility (Facility) is summarized on the cover page and in sections 1 and 2 of the Fact Sheet (Attachment F). Section 1 of the Fact Sheet also includes information regarding the Facility’s permit application. 2. FINDINGS The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 2.1. Legal Authorities. This Order serves as waste discharge requirements (WDRs) pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA) and implementing regulations adopted by the United States Environmental Protection Agency (U.S. EPA) and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as a National Pollutant Discharge Elimination System (NPDES) permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1 subject to the WDRs in this Order. 2.2. Background and Rationale for Requirements. The Central Coast Water Board developed the requirements in this Order based on information submitted as part of the application, through monitoring and reporting programs, and other available information. The Fact Sheet (Attachment F), which contains background information and rationale for the requirements in this Order, is hereby incorporated into and constitutes Findings for this Order. Attachments A through E are also incorporated into this Order. 2.3. Provisions and Requirements Implementing State Law. Some provisions/requirements in this Order are included to implement state law only . These provisions/requirements are not required or authorized under the federal CWA; consequently, violations of these provisions/requirements are not subject to the enforcement remedies that are available for NPDES violations. 2.4. Water Reclamation Requirements for Recycled Water Production and Use. This Order allows the production and use of disinfected secondary and tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements established by the California Department of Public Health in title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. Additionally, this Order includes water reclamation requirements for the Facility pursuant to the State Water Resources Control Board’s (State Water Board’s) Division of Drinking Water (DDW) recommendations submitted to the Central Coast Water Board. The distribution and offsite reuse of recycled water produced by the Facility is subject to the State Water Board’s General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW), or other applicable permit, dependent on final use. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 5 2.5. Response to Climate Change. Climate change refers to observed changes in regional weather patterns such as temperature, precipitation, and storm frequency and size. At the local scale, within urbanized areas, climate change may directly impact groundwater and surface water supply; drainage, flooding, and erosion patterns; and ecosystems and habitat. This shift in climate, combined with California’s growing population, has increased reliance on pumping, conveying, treating, and heating water, increasing the water sector’s greenhouse gas emissions. The State Water Board’s Resolution 2017 -0012, Comprehensive Response to Climate Change, requires a proactive response to climate change in all California Water Board actions, with the intent to embed climate change consideration into all programs and activities. Aligning with Resolution 2017 -0012, this Order supports the beneficial reuse of the Facility’s treated effluent to offset potable water supplies for irrigation and dedicated in -stream flows to support critical creek habitat. This Order incorporates requirements for the Facility to beneficially reuse treated effluent, which serves to diversify the State’s water supply portfolio to prepare for uncertainties in water resources due to the changing climate through ongoing implementation, monitoring, and updating of the Discharger’s climate action planning efforts using the best available data and technology for wastewater treatment and operation. In 2019, the City participated in the development of the Multi-Jurisdictional San Luis Obispo Hazard Mitigation, a planning effort that identifies and prioritizes the City’s vulnerability to hazards and outlines mitigation goals and objectives. In August 2020, the City adopted its Climate Action Plan with goals for community -wide carbon neutrality by 2035. Most recently, on January 17, 202 3, The City adopted the Climate Adaptation and Safety Element as part of its general plan. According to Disaster Mitigation Act (DMA) requirement §201.6(d)(3), the City must review and revise this plan within five years for continued mitigation project grant funding. Additionally, the City is currently undergoing construction of the SLO Water Plus project, which includes Facility upgrades to improve the Facility’s energy efficiency, provide flood protection improvements, increase treatment capacity, and improve resource recovery. To incorporate proactive planning for the future, this Order requires the Discharger to report on implementation progress, monitoring, and planning updates at this Facility as it relates to flooding, wildfire, renewable energy generation and energy efficiency, temperature, water recycling, biosolid s reuse, and influent flow and loading fluctuations exacerbated by climate change. 2.6. Human Right to Water. California Water Code section 106.3 established the policy that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. On January 26, 2017, the Central Coast Water Board adopted Resolution R3 -2017- 0004, which adopts the human right to water as a core value and affirms the realization of the human right to water and protecting human health as the Central Coast Water Board's top priorities. Consistent with the human right to water stated in California Water Code section 106.3, subdivision (a), and the Central Coast Water Board’s Resolution R3-2017-0004, this Order promotes actions that advance the human right to water and discourages actions that delay or impede opportunities for communities to secure safe, clean, affordable, and accessible CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 6 water adequate for human consumption, cooking, and sanitary purposes. This Order implements recently updated mercury water quality objectives that are more stringent than previous objectives to more adequately protect beneficial uses related to water and fish consumption. 2.7. Disadvantaged Community Status. Environmental Justice principles call for the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income in the development, adoption, implementation, and enforcement of all environmental laws, regulations, and policies that affect every community’s natural resources and the places people live, work, play, and learn. The Central Coast Water Board implements regulatory activities and water quality projects in a manner that ensures the fair treatment of all people, including Underrepresented Communities. Underrepresented Communities include but are not limited to Disadvantaged Communities (DACs), Severely Disadvantaged Communities (SDACs), Economically Distressed Areas (EDAs), Tribes, Environmentally Disadvantaged Communities (EnvDACs), and members of Fringe Communities.1 Furthermore, the Central Coast Water Board is committed to providing all stakeholders the opportunity to participate in the public process and provide meaningful input to decisions that affect communities. To meet environmental justice principles, staff has evaluated the disadvantaged community status for the Discharger. Using 2020 census data, the California Department of Water Resources Disadvantaged Community (DAC) Mapping Tool1 identifies 16 block groups in the City of San Luis Obispo, representing approximately 54 percent of the population, as disadvantaged communities. The tool defines a DAC as a census block with a median household income between $50,458 and $67,278 and a severely disadvantaged community (SDAC) as a census block with a median household income below $50,458. The SDAC census blocks in the City of San Luis Obispo have median household incomes of $8,075, $9,596, $11,935, $28,173, $28,284, $35,774, $39,526, and $44,167. The DAC census blocks in the City of San Luis Obispo have median household income of $51,074, $52,961, $55,769, $56,866, $57,175, $57,803, $58,083, and $60,417. 2.8. Notification of Interested Persons. The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provided them with an opportunity to submit their written comments and recommendations. Details of the notification are provided in the Fact Sheet, Attachment F. 2.9. Consideration of Public Comment. The Central Coast Water Board, in a public meeting, heard and considered all comments pertaining to the discharge. Details of the public hearing are provided in the Fact Sheet, Attachment F. THEREFORE, IT IS HEREBY ORDERED that this Order supersedes Order R3-2014- 0033, except for enforcement purposes, that Waste Discharge/Master Reclamation 1 The DAC Mapping Tool is used to inform statewide Integrated Water Resources Management (IRWM), Sustainable Groundwater Monitoring Act (SGMA), and California Water Plan implementation efforts and can be found at the following website: https://gis.water.ca.gov/app/dacs/. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 7 Requirements Order R3-2003-081 is terminated upon Discharger’s enrollment in State Water Board Order WQ-2016-0068-DDW, except for enforcement purposes, and, in order to meet the provisions contained in division 7 of the California Water Code (commencing with section 13000) and regulations adopted thereunder and the provisions of the CWA and regulations and guidelines adopted thereunder, the Discharger shall comply with the requirements in this Order. This action in no way prevents the Central Coast Water Board from taking enforcement action for violations of the previous orders. 3. DISCHARGE PROHIBITIONS 3.1. Discharge of treated wastewater at a location or in a manner other than as described by this Order at Discharge Points 001 and 002, with compliance measured at EFF-001 and EFF-002 respectively as described in the Monitoring and Reporting Program (MRP) Attachment E, is prohibited. 3.2. The discharge of any waste not specifically regulated by this Order, excluding stormwater regulated by General Permit CAS000001 (Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities), is prohibited. 3.3. The overflow or bypass of wastewater from the Discharger’s collection, treatment, or disposal facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7 (Bypass), is prohibited. 3.4. Creation of a condition of pollution, contamination, or nuisance, as defined by section 13050 of the California Water Code, is prohibited. 3.5. The discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat. 3.6. The discharge of radioactive substances is prohibited. 3.7. The average dry weather daily discharge flow shall not exceed 5.4 million gallons per day (MGD). 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS 4.1. Effluent Limitations – Discharge Point 001 4.1.1. Final Effluent Limitations – Discharge Point 001 4.1.1.1. The Discharger shall maintain compliance with the following effluent limitations at Discharge Point 001, with compliance measured at Monitoring Location EFF- 001A or EFF-001B as described in the Monitoring and Reporting Program (MRP), Attachment E. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 8 Table 2. Effluent Limitations at Discharge Point 001 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1,351 2,252 - - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - - TSS lbs/day[1] 425 1,351 3,378 - - - - pH[2],[3] standard units - - - 7.0 8.3 - - Oil and Grease mg/L 5 - 10 - - - - Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - - Dissolved Oxygen mg/L - - - 4.0 - - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.01 2 - 0.024 - - - - Chlorodibromom ethane (Dibromochlorom ethane) µg/L 0.40 - 0.81 - - - - Chloroform µg/L 60 - 120.6 - - - - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 9 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Dichlorobromom ethane µg/L 0.56 - 0.96 - - - - Methylene Chloride µg/L 4.7 - 9.45 - - - - Pentachlorophen ol µg/L 0.28 - 0.56 - - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - - Nitrite, Total mg/L 1 - - - - - - Un-ionized Ammonia mg/L 0.02 5 - - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - - Molybdenum mg/L 0.01 - - - - - - Total Dissolved Solids mg/L - - - - - 650[10] Chloride mg/L - - - - - 100[10] Sodium mg/L - - - - - 50[10] Sulfate mg/L -- - - - - 100[10] Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail ” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 10 [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 7.0-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 7.0-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0 -9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 7.0-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 - day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in -stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP -Attachment E). [10] Based on a 12-month running mean. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 11 4.1.1.2. Percent Removal: The average monthly percent removal of BOD 5-day at 20°C and total suspended solids shall not be less than 85 percent. 4.1.1.3. Floating Material: Discharge of treated wastewater through Discharge Point 001 shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 4.1.2. Interim Effluent Limitations – Not Applicable 4.2. Land Discharge Specifications – Not Applicable 4.3. Recycling Specifications – Discharge Point 002 As specified below, this Order conditionally authorizes the Discharger to act as the producer of recycled (or reclaimed) water and to reuse recycled water onsite at the Facility and for other purposes. The Discharger is responsible for compliance with all applicable requirements associated with the production and onsite use of recycled water as specified within this Order. The Discharger filed a California Code of Regulations title 22 engineering report on August 14, 2020, that described recycled water quality produced at the Facility as "disinfected tertiary" (as defined in title 22, section 60301.230) and submitted a Notice of Intent (NOI) on August 14, 2020, to enroll under the State Water Board General Water Reclamation Requirements for Recycled Water Use (Order WQ 2016-0068-DDW). The distribution and offsite reuse of recycled water produced by the Facility are subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. Order WQ 2016-0068-DDW supersedes Waste Discharge/Master Reclamation Requirements Order R3-2003-081. 4.3.1. Reclamation and use of treated wastewater shall adhere to applicable requirements of California Water Code sections 13500-13577 (Water Reclamation) and California Code of Regulations, title 17 sections 7583-7586, title 17 sections 7601-7605, and title 22 sections 60301-60355 (Uniform Statewide Recycling Criteria). 4.3.2. Recycled water production shall comply with a title 22 engineering report approved by DDW that demonstrates or defines compliance with the Uniform Statewide Recycling Criteria. 4.3.3. Recycled water shall be disinfected tertiary recycled water, as defined by California Code of Regulations title 22, section 60301.230. 4.3.4. Recycled water shall be adequately filtered, and disinfected, as defined in title 22. 4.3.5. Turbidity in tertiary recycled water shall not exceed any of the following limits: 4.3.5.1. An average of 0.2 NTU within a 24-hour period; and 4.3.5.2. 0.5 NTU at any time. 4.3.6. Total coliform bacteria measured in the disinfected recycled water shall not exceed the following limits: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 12 4.3.6.1. An MPN of 2.2 per 100 mL calculated as a median concentration utilizing the bacteriological results of the last seven days for which analyses have been completed, 4.3.6.2. An MPN of 23 per 100 mL in more than one sample in any 30-day period, and 4.3.6.3. No sample shall exceed an MPN of 240 total coliform bacteria per 100 mL. 4.3.7. The Discharger shall discontinue delivery of recycled water to distributors and users during any period in which it has reason to believe that the limits established in this Order are not being met. The delivery of recycled water shall not be resumed until all conditions that caused the limits to be violated have been corrected. 4.3.8. Recycled water shall not exceed any maximum contaminant level established pursuant to sections 116275(c)(1) and (d) of the California Health and Safety Code or established by the U.S. EPA. 4.3.9. Recycled water disinfected with chlorine shall have a chlorine concentration time modal contact time (CT) value of not less than 450 mg-min/L at all times with a modal contact time of at least 90 minutes based on peak dry weather design flow. 4.3.10 If a disinfection method other than chlorine is used, the disinfection process shall be a process that, when combined with the filtration process, has been demonstrated to inactivate and/or remove 99.999 percent of the plaque forming units of F-specific bacteriophage MS2, or polio virus in the wastewater. A virus that is at least as resistant to disinfection as polio virus may be used for purposes of the demonstration. 4.3.11. The Discharger shall adhere to the manufacturer’s recommended operating conditions for the ultraviolet (UV) system. 4.3.12. Personnel involved in producing, transporting, or using recycled water shall be informed of possible health hazards that may result from contact and use of recycled water. 4.3.13. All areas where recycled water is in use and with public access shall be posted with signs in English and an international symbol to warn the public that recycled wastewater is being stored or used. 4.3.14. Recycled water systems at the Facility shall be properly labeled and regularly inspected to ensure proper operation, absence of leaks, and absence of illegal connections. 5. RECEIVING WATER LIMITATIONS 5.1. Surface Water Limitations Receiving water limitations are based on water quality objectives contained in the Water Quality Control Plan for the Central Coastal Basin (Basin Plan) and are a required part of this Order. The discharge shall not cause a violation of the following receiving water limitations in San Luis Obispo Creek. The discharge from the wastewater treatment facility shall comply with the following in the receiving waters: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 13 5.1.1. Waters shall be free of coloration that causes nuisance or adversely affects beneficial uses. Coloration attributable to materials of waste origin shall not be greater than 15 units or 10 percent above natural background color, whichever is greater. 5.1.2. Waters shall not contain taste or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, that cause nuisance, or that adversely affect beneficial uses. 5.1.3. Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.4. Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.5. Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. 5.1.6. Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. 5.1.7. Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses. 5.1.8. The suspended sediment load and suspended sediment discharge rate to surface waters shall not be altered in such a manner as to cause nuisance or adversely affect beneficial uses. 5.1.9 Concentrations of toxic metals and inorganic chemicals in waters shall not be increased in such a manner that may adversely affect beneficial uses. 5.1.10. Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Increase in turbidity attributable to controllable water quality factors shall not exceed the following limits. 5.1.10.1. Where natural turbidity is between 0 and 50 NTUs, increases shall not exceed 20 percent. 5.1.10.2. Where natural turbidity is between 50 and 100 NTUs, increases shall not exceed 10 NTU. 5.1.10.3. Where natural turbidity is greater than 100 NTUs, increases shall not exceed 10 percent. 5.1.11. The pH value shall not be depressed below 7.0 nor raised above 8.3. The change in normal ambient pH levels shall not exceed 0.5 units. 5.1.12. Dissolved oxygen concentrations in receiving waters shall not be reduced below 7.0 mg/L at any time. 5.1.13. Discharged effluent shall not cause the receiving water temperature to increase more than 5° Fahrenheit (F) above the receiving water temperature. If, due to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 14 the Creek’s low temperature as determined by early-morning monitoring, the discharge causes the Creek’s temperature to exceed the limit, the Discharger must ensure the discharge shall not cause the receiving water to exceed 72.5° F (22.5° C). The discharger shall monitor the Creek again four hours after discovering the exceedance and shall report both results to the Executive Officer in the monthly self-monitoring report. 5.1.14. All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge. 5.1.15. The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/L (as N) in the receiving water. 5.1.16. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect the beneficial uses of the receiving water. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life. For waters where existing concentrations are presently nondetectable or where beneficial uses would be impaired by concentrations in excess of nondetectable levels, total identifiable chlorinated hydrocarbon pesticides shall not be present at concentrations detectable within the accuracy of analytical methods as prescribed in Standard Methods for the Examination of Water and Wastewater, latest edition, or other equivalent methods approved by the Executive Officer. 5.1.17. Waters shall not contain organic substances in concentrations greater than those listed in the table below: Table 3. Organic Substances Water Quality Criteria Parameter Units Water Quality Objective Methylene Blue Activated Substances mg/L 0.2 Phenols ug/L 1.0 Polychlorinated Biphenyls (PCBs) [1] µg/L 0.3 Phthalate Esters µg/L 0.002 [1] PCBs refer to sum of PCB 1016, 1221, 1232, 1242, 1248, 1254, and 1260. 5.1.18. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstance shall receiving waters contain concentrations of radionuclides in excess of the maximum contaminant levels (MCLs) for radioactivity presented in title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.1.19. Receiving waters shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 15 Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.1.20. Receiving waters shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural beneficial use . Interpretation of adverse effects shall be derived from the University of California Agricultural Extension Service guidelines presented in section 3, Table 3-1 of the 2019 Basin Plan. 5.1.21. Receiving waters shall not contain concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in section 3, Table 3-2 of the Basin Plan. Salt concentrations for irrigations waters shall be controlled through implementation of the anti-degradation policy to the effect that mineral constituents of currently or potentially usable waters shall not be increased. 5.1.22. Receiving waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife in excess of the levels presented in section 3, Table 3-3 of the 2019 Basin Plan. The concentrations of metals listed in the table below shall not be exceeded for the protection of aquatic life. Table 4. Hardness Dependent Metals Criteria Parameter Units Receiving Water Hardness >100 mg/L calcium carbonate (CaCO3) Receiving Water Hardness <100 mg/L CaCO3 Cadmium mg/L 0.003 0.0004 Chromium mg/L 0.05 0.05 Copper mg/L 0.03 0.01 Lead mg/L 0.03 0.03 Mercury mg/L 0.0002 0.0002 Nickel mg/L 0.4 0.1 Zinc mg/L 0.2 0.004 5.1.23. E. coli concentrations shall not exceed 100 MPN/100 mL as a 6-week rolling geometric mean, calculated weekly. A statistical threshold value (STV) of 320 MPN/100 mL for E. coli shall not be exceeded by more than 10 percent of samples collected in a calendar month, calculated in a static manner. 5.1.24. Discharges shall not cause receiving water to exceed the water quality objectives for the Estero Bay Hydrologic Unit (San Luis Obispo Creek Sub-Area) specifically identified by Table 3-5 of the 2019 Basin Plan, as shown in the table below. Objectives shown are annual mean values. Objectives are based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 5. Annual Mean Surface Water Quality Objectives CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 16 Parameter Units Annual Mean Total Dissolved Solids mg/L 650 Chloride mg/L 100 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 5.2. Groundwater Limitations Activities at the Facility shall not cause exceedance/deviation from the following water quality objectives for groundwater established by the 2019 Basin Plan. The Central Coast Water Board may require the Discharger to investigate the cause of exceedances in the groundwater before determining whether the Discharger caused any water condition that exceeds the following groundwater limitations. 5.2.1. Groundwater shall not contain taste or odor-producing substances in concentrations that adversely affect beneficial uses. 5.2.2. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstances shall groundwater contain concentrations of radionuclides in excess of the MCLs for radioactivity presented in Title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.2.3. The Discharger shall not cause a statistically significant increase of mineral constituent concentrations in underlying groundwater as determined by comparison of samples collected from wells located up-gradient and down- gradient of the waters affected by the discharge. 5.2.4. The median concentration of coliform organisms in groundwater, over any seven - day period, shall be less than 2.2 organisms per 100 mL. 5.2.5. Groundwater shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431 -A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.2.6. Groundwater shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural supply beneficial use. Interpretation of adverse effects shall be as derived in University of California Agricultural Extension Service guidelines provided in Table 3-1 of the 2019 Basin Plan. 5.2.7. Groundwater used for irrigation and livestock watering shall not exceed concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in chapter 3, Table 3 -2 of the 2019 Basin Plan. 5.2.8. Groundwater shall not contain constituents greater than the following concentrations established in Table 3-6 of the 2019 Basin Plan for groundwaters within the San Luis Obispo Creek sub-area (Estero Bay sub-basin). Objectives CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 17 shown are annual median values. Objectives based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 6. Groundwater Objectives Parameter Units Annual Median TDS mg/L 900 Chloride mg/L 200 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 Nitrogen mg/L 5 6. PROVISIONS 6.1. Standard Provisions 6.1.1. The Discharger shall comply with all Standard Provisions included in Attachment D. 6.1.2. The Discharger shall comply with Central Coast Water Board Standard Provisions in Attachment D. In the event that there is any conflict, duplication, or overlap between provisions specified by this Order, the more stringent provision shall apply. 6.2. Monitoring and Reporting Program (MRP) Requirements The Discharger shall comply with the MRP, and future revisions thereto, in Attachment E. 6.3. Special Provisions 6.3.1. Reopener Provisions 6.3.1.1. This Order may be reopened for modification, or revocation and reissuance, as a result of the detection of a reportable priority pollutant generated by special conditions included in this Order. These special conditions may be, but are not limited to, fish tissue sampling, whole effluent toxicity, monitoring requirements on internal waste stream(s), monitoring for surrogate parameters, and other new information. Additional requirements may be included in this Order as a result of the special condition monitoring data. 6.3.1.2. This Order may be reopened and modified in accordance with NPDES regulations at 40 Code of Federal Regulations (CFR) parts 122 and 124, as necessary, to include additional conditions or limitations based on newly available information or to implement any U.S. EPA approved, new, state water quality objective. 6.3.1.3. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 18 to cause, or contributes to an excursion above a State Implementation Policy (SIP) water quality objective. 6.3.1.4. This Order may be reopened and modified to revise the most sensitive species to be used for acute and/or chronic aquatic toxicity testing once the required species sensitivity is completed in accordance with section 5 of the MRP (Attachment E). Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. 6.3.1.5 This Order may be reopened and modified to reevaluate reasonable potential for acute toxicity, and establish acute toxicity effluent limitations, if warranted, after the evaluation of new data and information. 6.3.2. Special Studies, Technical Papers and Additional Monitoring Requirements 6.3.2.1. Toxicity Reduction Requirements For compliance with the Basin Plan’s narrative toxicity objective, this Order requires the Discharger to conduct acute and chronic whole effluent toxicity (WET) testing, as specified in section 5 of the MRP. Furthermore, this Provision requires the Discharger to investigate the causes of and identify corrective actions to reduce or eliminate effluent toxicity. If the discharge exceeds the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring established in this Provision, the Discharger is required to initiate a Toxicity Reduction Evaluation (TRE) in accordance with an approved TRE Work Plan and take actions to mitigate the impact of the discharge and prevent recurrence of toxicity. A TRE is a site-specific study conducted in a stepwise process to identify the source(s) of toxicity and the effective control measures for effluent toxicity. TREs are designed to identify the causative agents and sources of whole effluent toxicity, evaluate the effectiveness of the toxicity control options, and confirm the reduction in effluent toxicity. This Provision includes requirements for the Discharger to update and submit their TRE Work Plan and includes procedures for accelerated toxicity monitoring and TRE initiation: 6.3.2.1.1. TRE Work Plan. Within 90 days of the effective date of this Order, the Discharger shall submit to the Central Coast Water Board an updated TRE Work Plan for approval by the Executive Officer. The TRE Work Plan shall outline the procedures for identifying the source(s) of and reducing or eliminating effluent toxicity. The TRE Work Plan must be developed in accordance with U.S. EPA guidance and be of adequate detail to allow the Discharger to immediately initiate a TRE as required in this Provision. 6.3.2.1.2. Accelerated Monitoring and TRE Initiation. When the numeric toxicity monitoring trigger or effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all test acceptability criteria (TAC), the Discharger shall initiate accelerated monitoring as required in the Accele rated Monitoring Specifications in section 5 of the MRP. The Discharger shall initiate a TRE to address effluent toxicity if any WET testing results exceed CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 19 the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring. 6.3.3. Best Management Practices and Pollution Prevention 6.3.3.1. Salt and Nutrient Management Program 6.3.3.1.1 The Discharger shall continue to update and implement an ongoing Salt Management Program, with the intent of reducing mass loading of salts in treated effluent and attainment of applicable water quality objectives for salts in the San Luis Obispo Creek Sub-Basin Area of the Estero Bay Drainage Basin. Additionally, the Discharger shall continue to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable water quality objectives for nutrients in the same basin. 6.3.3.1.2 Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. 6.3.3.1.3 Nutrient reduction measures shall focus on optimizing wastewater treatment processes for nitrification and denitrification, or other means of nitrogen removal. Reduction measures may also include source control (non-human waste from commercial and industrial sources) as appropriate. 6.3.3.1.4 As part of the Salt and Nutrient Management Program, the Discharger shall submit an annual report describing salt and nutrient reduction efforts as described in the section 9.3 of the MRP (Attachment E). 6.3.3.1.5 As an alternative to the Salt and Nutrient Management Program requirements described above, upon Executive Officer approval, the Discharger may submit documentation and summary of participation in a regional salt/nutrient management plan implemented under the provisions of State Water Board Resolution No. 2018-0057 (Recycled Water Policy). 6.3.3.2. Pollutant Minimization Program 6.3.3.2.1.The Discharger shall develop and conduct a Pollutant Minimization Program (PMP) as further described below when there is evidence (e.g., sample results reported as detected not quantifiable (DNQ) when the effluent limitation is less than the MDL, sample results from analytical methods more sensitive than those methods required by this Order, presence of whole effluent toxicity, health advisories for fish consumption, results of benthic or aquatic organism tissue sampling) that a priority pollutant is present in the effluent above an effluent limitation and either: 6.3.3.2.1.1. A sample result is reported as DNQ and the effluent limitation is less than the reporting limit (RL); or 6.3.3.2.1.2. A sample result is reported as non-detect (ND) and the effluent limitation is less than the MDL, using definitions described in Attachment A and reporting protocols described in MRP section 10.2.4. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 20 6.3.3.2.2. The PMP shall include, but not be limited to, the following actions and submittals acceptable to the Central Coast Water Board Executive Officer: 6.3.3.2.2.1. An annual review and semi-annual monitoring of potential sources of the reportable priority pollutant(s), which may include fish tissue monitoring and other bio-uptake sampling; 6.3.3.2.2.2. Quarterly monitoring for the reportable priority pollutant(s) in the influent to the wastewater treatment system; 6.3.3.2.2.3. Submittal of a control strategy designed to proceed toward the goal of maintaining concentrations of the reportable priority pollutant(s) in the effluent at or below the effluent limitation; 6.3.3.2.2.4. Implementation of appropriate cost-effective control measures for the reportable priority pollutant(s), consistent with the control strategy; and 6.3.3.1.2.5. An annual status report that shall be sent to the Central Coast Water Board including: 6.3.3.1.2.5.1. All PMP monitoring results for the previous year; 6.3.3.1.2.5.2. A list of potential sources of the reportable priority pollutant(s); 6.3.3.1.2.5.3. A summary of all actions undertaken pursuant to the control strategy; and 6.3.3.1.2.5.4. A description of actions to be taken in the following year. 6.3.4. Construction, Operation and Maintenance Specifications 6.3.4.1. The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.3.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.3.5.1. Biosolids. The handling, management, and disposal of sludge and solids derived from wastewater treatment must comply with applicable provisions of U.S. EPA regulations at 40 CFR sections 257, 258, 501, and 503, including all monitoring, record keeping, and reporting requirements. Solids and sludge treatment, storage, and disposal or reuse shall not create a nuisance, such as objectionable odors or flies, and shall not result in ground water contamination. Sites for solids and sludge treatment and storage shall have adequate facilities to divert surface water runoff from adjacent areas to protect the boundaries of such sites from erosion, and to prevent drainage from treatment and storage sites. The treatment, storage, disposal, or reuse of sewage sludge and solids shall not cause waste material to be in a position where it is, or can be, conveyed from the treatment and storage sites and deposited into waters of the State. The Discharger is responsible for assuring that all biosolids produced at its facility are used or disposed of in accordance with the above rules, regardless of whether the Discharger uses or disposes of the biosolids itself, or transfers them to another party for further treatment, use, or disposal. The Discharger is CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 21 responsible for informing subsequent preparers, appliers, and disposers of the requirements that they must adhere to these rules. 6.3.5.2. Pretreatment. The Discharger shall be responsible for the performance for all pretreatment requirements contained in 40 CFR part 403 and shall be subject to enforcement actions, penalties, fines, and other remedies by the U.S. EPA, or other appropriate parties, as provided in the CWA, as amended (33 USC 1351 et seq.). The Discharger shall implement and enforce its approved POTW Pretreatment Program. The Discharger’s approved POTW Pretreatment Program is hereby made an enforceable condition of this permit. U.S. EPA or the Central Coast Water Board may initiate enforcement action against an industrial user for noncompliance with applicable standards and requirements as provided in the CWA. The Discharger shall enforce the requirements promulgated under sections 307 (b), 307 (c), 307 (d), and 402 (b) of the CWA. The Discharger shall cause industrial users subject to Federal Categorical Standards to achieve compliance no later than the date specified in those requirements or, in the case of a new industrial user, upon commencement of the discharge. The Discharger shall perform the pretreatment functions as required in 40 CFR part 403, including, but not limited to the following: 6.3.5.2.1. Implement the necessary authorities as provided in 40 CFR section 403.8 (f) (1); 6.3.5.2.2. Enforce the pretreatment requirements under 40 CFR sections 403.5 and 403.6; 6.3.5.2.3. Implement the programmatic functions as provided in 40 CFR section 403.8 (f) (2); and 6.3.5.2.4. Provide the requisite funding and personnel to implement the pretreatment program as provided in 40 CFR section 403.8 (f) (3). 6.3.5.5. Resource Recovery from Anaerobically Digestible Material. If the Discharger will receive hauled-in anaerobically digestible material for injection into an anaerobic digester, the Discharger shall notify the Central Coast Water Board and develop and implement standard operating procedures for this activity. The standard operating procedures shall be developed prior to receiving hauled-in anaerobically digestible material. The standard operating procedures shall address material handling, including unloading, screening, or other processing prior to anaerobic digestion; transportation; spill prevention; and spill response. In addition, the standard operating procedures shall address avoidance of the introduction of materials that could cause interference, pass- through, or upset of the treatment processes; avoidance of prohibited material; vector control; odor control; operation and maintenance; and the disposit ion of any solid waste segregated from introduction to the digester. The Discharger shall train its staff on the standard operating procedures and shall maintain records for a minimum of five years for each load received, describing the hauler, waste type, and quantity received. In addition, the Discharger shall CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 22 maintain records for a minimum of five years for the disposition, location, and quantity of cumulative pre-digestion-segregated solid waste hauled offsite. 6.3.6. Other Special Provisions 6.3.6.1. Salt Management. Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. The Discharger shall assess additional pretreatment measures that may be taken to reduce influent salt concentrations and include a discussion of proposed and implemented measures in the annual report described below. The Discharger must also implement outreach to residential, commercial, and industrial salt contributors with the goal of reducing salts discharged to the collection system. 6.3.6.2. Discharges of Stormwater. For the control of stormwater discharged from the site of the wastewater treatment and disposal facilities, if applicable, the Discharger shall seek authorization to discharge under and meet the requirements of the State Water Board’s Water Quality Order 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.3.6.3. Statewide General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order No. 2022-0103-DWQ) The Discharger is subject to the requirements of and must separately comply with State Water Board Order 2022-0103-DWQ, Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems, including monitoring and reporting requirements, and any subsequent revision to that order. This General Permit, adopted on December 6, 2022, is applicable to all “federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California.” The purpose of the General Permit is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled under the General Permit. 6.3.6.4. Climate Change Adaptation Implementation Progress Report. On May 1, 2029, the Discharger shall submit a Climate Change Adaptation Implementation Progress Report2 to the Central Coast Water Board Executive Officer describing the Discharger’s progress in implementing, monitoring, and updating its long-term approach for identifying and addressing climate change hazards and vulnerabilities at the Facility, including all associated infrastructure (e.g., treatment facilities, conveyances to discharge points, discharge facilities). 2 In place of a static document, the Discharger may develop a living document and/or set of tools that fulfills the components outlined for the Climate Change Adaptation Program. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 23 The Climate Change Adaptation Implementation Report shall, at a minimum, include the following components: 6.3.6.4.1. Climate Change Adaptation Implementation Status – Provide a status update on any city or county-wide reports that address Facility and or collection system climate change adaptation planning and or implantation. Submit copies of document(s) to CIWQS as attachments. 6.3.6.4.2. Resiliency Actions – Report progress on actions that build facility and operational resilience to identified vulnerabilities, accounting for options that minimize resource impacts. For the anticipated life of the facility, include an analysis of: • Precipitation pattern changes o Drought – Decreased influent quantity and quality o Peak Events – Flooding and increased influent quantity • Temperature fluctuations and extremes • Increased wildfires • Energy resilience o Energy efficiency o Renewable energy generation o Increased power outages • Biosolid reuse • Water recycling 6.3.6.4.3. Adaptation Strategy – Report progress and adjustments made to strategy to complete Resiliency Actions, encompassing the following: 6.3.6.4.3.1. Prioritization – How resiliency actions were prioritized based on risks to water quality, but also accounting for costs and benefits. 6.3.6.4.3.2. Schedule and Milestones – Ongoing and changing timeframes to complete prioritized resiliency actions and/or climate change hazard triggers to inform when the Discharger shall implement actions. Milestones to complete critical steps for prioritized Resiliency Actions, designed to demonstrate measurable progress at a steady, or accelerated, completion pace over the established timeframes. 6.3.6.4.3.3. Financial Planning – Costs of reported implementation and monitoring measures, projected costs necessary to continue implementation and monitoring of resiliency actions, and strategy to procure funds. 6.3.7. Compliance Schedules – Not Applicable 7. COMPLIANCE DETERMINATION 7.1. General Compliance with effluent limitations for reportable pollutants shall be determined using sample reporting protocols defined in the MRP and Attachment A of this Order. For purposes of reporting and administrative enforcement by the Central Coast and State Water Boards, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the reportable pollutant in the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 24 monitoring sample is greater than the effluent limitation and greater than or equal to the reported Minimum Level (ML). 7.2. Chronic Toxicity The discharge is subject to determination of “Pass” or “Fail” from a chronic toxicity test using the Test of Significant Toxicity (TST) statistical t-test approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. The null hypothesis (Ho) for the TST statistical approach is: Mean discharge “in-stream” waste concentration (IWC) response ≤0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub -lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge (100 percent effluent) and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be reported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). 7.3. Multiple Sample Data When determining compliance with a measure of central tendency (arithmetic mean, geometric mean, median, etc.) of multiple samples analyses and the data set contains one or more reported determinations of DNQ, or ND, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 7.3.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 7.3.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 25 even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 7.4. Average Monthly Effluent Limitation (AMEL) If the average of daily discharges over a calendar month exceeds the AMEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that month for that parameter (e.g., resulting in 31 days of non-compliance in a 31-day month). The average of daily discharges over the calendar month that exceeds the AMEL for a parameter will be considered out of compliance for that month only. If only a single sample is taken during the calendar month and the analytical result for that sample exceeds the AMEL, the Discharger will be considered out of compliance for that calendar month. For any one calendar month during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar month. 7.5. Average Weekly Effluent Limitation (AWEL) If the average of daily discharges over a calendar week exceeds the AWEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that week for that parameter, resulting in seven days of non-compliance. The average of daily discharges over the calendar week that exceeds the AWEL for a parameter will be considered out of compliance for that week only. If only a single sample is taken during the calendar week and the analytical result for that sample exceeds the AWEL, the Discharger will be considered out of compliance for that calendar week. For any one calendar week during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar week. 7.6. Maximum Daily Effluent Limitation (MDEL) If a daily discharge exceeds the MDEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for that parameter for that one day only within the reporting period. For any one day during which no sample is taken, no compliance determination can be made for that day. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-1 A. ATTACHMENT A – DEFINITIONS Arithmetic Mean (μ) Also called the average, is the sum of measured values divided by the number of samples. For ambient water concentrations, the arithmetic mean is calculated as follows: where: Σx is the sum of the measured ambient water concentrations, and n is the number of samples. Average Monthly Effluent Limitation (AMEL) The highest allowable average of daily discharges over a calendar month, calculated as the sum of all daily discharges measured during a calendar month divided by the number of daily discharges measured during that month. Average Weekly Effluent Limitation (AWEL) The highest allowable average of daily discharges over a calendar week (Sunday through Saturday), calculated as the sum of all daily discharges measured during a calendar week divided by the number of daily discharges measured during that week. Bioaccumulative Those substances taken up by an organism from its surrounding medium through gill membranes, epithelial tissue, or from food and subsequently concentrated and retained in the body of the organism. Bioassay A test used to evaluate the relative potency of a chemical or a mixture of chemicals by comparing its effect on a living organism with the effect of a standard preparation on the same type of organism. Calendar Month(s) A period of time from a day of one month to the day before the corresponding day of the next month if the corresponding day exists, or if not to the last day of the next month (e.g., from January 1 to January 31, from June 15 to July 14, or from January 31 to February 28). Calendar Quarter A period of time defined as three consecutive calendar months. Calendar Year A period of time defined as twelve consecutive calendar months. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-2 Carcinogenic Pollutants are substances that are known to cause cancer in living organisms. Chronic Aquatic Toxicity Test A test to determine an adverse effect (sublethal or lethal) on a group of aquatic test organisms during an exposure of duration long enough to assess sub -lethal effects. Compliance with the effluent limitation for chronic toxicity in this Order is demonstr ated by conducting chronic toxicity tests for the effluent as described in section 7.15 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E), and in accordance with the TST statistical approach. Coefficient of Variation (CV) CV is a measure of the data variability and is calculated as the estimated standard deviation divided by the arithmetic mean of the observed values. Continuous Dischargers Facilities that discharge without interruption throughout its operating hours, except for infrequent shutdowns for maintenance, process changes, or other similar activities, and that discharge throughout the calendar year. Daily Discharge Daily Discharge is defined as either: (1) the total mass of the constituent discharged over the calendar day (12:00 am through 11:59 pm) or any 24 -hour period that reasonably represents a calendar day for purposes of sampling (as specified in the permit), for a constituent with limitations expressed in units of mass or; (2) the unweighted arithmetic mean measurement of the constituent over the day for a constituent with limitations expressed in other units of measurement (e.g., concentration). The daily discharge may be determined by the analytical results of a composite sample taken over the course of one day (a calendar day or other 24-hour period defined as a day) or by the arithmetic mean of analytical results from one or more grab samples taken over the course of the day. For composite sampling, if one day is defined as a 24-hour period other than a calendar day, the analytical result for the 24-hour period will be considered as the result for the calendar day in which the 24-hour period ends. Detected, but Not Quantified (DNQ) DNQ are those sample results less than the reporting limit (RL), but greater than or equal to the laboratory’s MDL. Sample results reported as DNQ are estimated concentrations. Dilution Credit Dilution Credit is the amount of dilution granted to a discharge in the calculation of a water quality-based effluent limitation, based on the allowance of a specified mixing zone. It is calculated from the dilution ratio or determined through conducting a mixing zone study or modeling of the discharge and receiving water. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-3 Dilution Ratio The critical low flow of the upstream receiving water divided by the flow of the effluent discharged. Effluent Concentration Allowance (ECA) ECA is a value derived from the water quality criterion/objective, dilution credit, and ambient background concentration that is used, in conjunction with the coefficient of variation for the effluent monitoring data, to calculate a long -term average (LTA) discharge concentration. The ECA has the same meaning as wasteload allocation (WLA) as used in United States Environmental Protection Agency (U.S. EPA) guidance (Technical Support Document for Water Quality-based Toxics Control, March 1991, second printing, EPA/505/2-90-001). Enclosed Bays Enclosed Bays means indentations along the coast that enclose an area of oceanic water within distinct headlands or harbor works. Enclosed bays include all bays where the narrowest distance between the headlands or outermost harbor works is less than 75 percent of the greatest dimension of the enclosed portion of the bay. Enclosed bays include, but are not limited to, Humboldt Bay, Bodega Harbor, Tomales Bay, Drake’s Estero, San Francisco Bay, Morro Bay, Los Angeles-Long Beach Harbor, Upper and Lower Newport Bay, Mission Bay, and San Diego Bay. Enclosed bays do not include inland surface waters or ocean waters. Estimated Chemical Concentration The estimated chemical concentration that results from the confirmed detection of the substance by the analytical method below the minimum level (ML) value. Estuaries and Coastal Lagoons Estuaries means waters, including coastal lagoons, located at the mouths of streams that serve as areas of mixing for fresh and ocean waters. Coastal lagoons and mouths of streams that are temporarily separated from the ocean by sandbars shall be considered estuaries. Estuarine waters shall be considered to extend from a bay or the open ocean to a point upstream where there is no significant mixing of fresh water and seawater. Estuarine waters included, but are not limited to, the Sacramento-San Joaquin Delta, as defined in California Water Code section 12220, Suisun Bay, Carquinez Strait downstream to the Carquinez Bridge, and appropriate areas of the Smith, Mad, Eel, Noyo, Russian, Klamath, San Diego, and Otay rivers. Estuaries do not include inland surface waters or ocean waters. Flow-Through Acute Toxicity Testing Systems A toxicity testing system where an effluent sample is either pumped continuously from the sampling point directly to a dilutor system, or collected and placed in a tank adjacent to the test laboratory and pumped continuously from the tank to a dilutor syst em. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-4 Inland Surface Waters All surface waters of the state that do not include the ocean, enclosed bays, or estuaries. Insignificant Dischargers National Pollutant Discharge Elimination System (NPDES) discharges that are determined to be a very low threat to water quality by the permitting authority. Instantaneous Maximum Effluent Limitation The highest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous maximum limitation). Instantaneous Minimum Effluent Limitation The lowest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous minimum limitation). In-stream Waste Concentration (IWC) The concentration of effluent in the receiving water after mixing as determined by the permitting authority. For purposes of aquatic toxicity testing for non-stormwater NPDES dischargers, the IWC shall be as described in section III.C.1 of the Toxicity Provisions. For assessing whether receiving waters meet the numeric water quality objectives (WQOs), the undiluted ambient water shall be used as the IWC in the TST as indicated in section III.B.3 of the Toxicity Provisions. Maximum Daily Effluent Limitation (MDEL) The highest allowable daily discharge of a pollutant, over a calendar day (or 24 -hour period). For pollutants with limitations expressed in units of mass, the daily discharge is calculated as the total mass of the pollutant discharged over the day. For pollutants with limitations expressed in other units of measurement, the daily discharge is calculated as the arithmetic mean measurement of the pollutant over the day. For the purposes of chronic and acute aquatic toxicity, an MDEL is an effluent limitation based on the outcome of the TST approach and the resulting percent effect at the IWC, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Maximum Daily Effluent Target (MDET) For the purposes of chronic and acute aquatic toxicity, an MDET is a target used to determine whether a Toxicity Reduction Evaluation (TRE) should be conducted. Not meeting the MDET is not a violation of an effluent limitation. Median The middle measurement in a set of data. The median of a set of data is found by first arranging the measurements in order of magnitude (either increasing or decreasing order) If the number of measurements (n) is odd, then: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-5 If n is even, then: (i.e., the midpoint between the (n/2 and ((n/2)+1))). Median Monthly Effluent Limitation (MMEL) For the purposes of chronic and acute aquatic toxicity, an MMEL is an effluent limitation based on a maximum of three independent toxicity tests, analyzed using the TST, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Median Monthly Effluent Target (MMET) For the purposes of chronic and acute aquatic toxicity, an MMET is a target based on a maximum of three independent toxicity tests used to determine whether a TRE should be conducted. Not meeting the MMET is not a violation of an effluent limitation. Method Detection Limit (MDL) MDL is the minimum concentration of a substance that can be reported with 99 percent confidence that the measured concentration is distinguishable from method blank results, as defined in 40 Code of Federal Regulations (CFR) part 136, Attachment B. Minimum Level (ML) ML is the concentration at which the entire analytical system must give a recognizable signal and acceptable calibration point. The ML is the concentration in a sample that is equivalent to the concentration of the lowest calibration standard analyzed by a specific analytical procedure, assuming that all the method specified sample weights, volumes, and processing steps have been followed. Mixing Zone Mixing Zone is a limited volume of receiving water that is allocated for mixing with a wastewater discharge where water quality criteria can be exceeded without causing adverse effects to the overall water body. MMEL Compliance Tests For the purposes of chronic and acute aquatic toxicity, MMEL compliance tests are a maximum of two tests that are used in addition to the routine monitoring test to determine compliance with the chronic and acute aquatic toxicity MMEL and MDEL. MMET Tests For the purposes of chronic and acute aquatic toxicity, for dischargers not required to comply with numeric chronic toxicity effluent limitations, MMET tests are a maximum of two tests that are used in addition to the routine monitoring test to determine w hether a TRE should be conducted. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-6 Most Sensitive Species The single species selected from an array of test species to be used in a single species laboratory test series to determine toxic effects of effluent or ambient water. Non-Continuous Dischargers Dischargers that do not discharge in a continuous manner or do not discharge throughout the calendar year (e.g., intermittent and seasonal dischargers). Non-NPDES Dischargers Dischargers of waste that could affect the quality of waters of the State that are not regulated by the NPDES program. Non-Stormwater NPDES Dischargers Dischargers that are regulated pursuant to one or more NPDES permit(s), but excluding any discharges subject to the United States Code title 33 section 1342(p). This includes dischargers that discharge a combination of treated municipal or industrial wastewater and stormwater. Nonpoint Source A source that does not meet the definition of a point source, as defined below. Not Detected (ND) Sample results which are less than the laboratory’s MDL. Null Hypothesis A statement used in statistical testing that has been put forward either because it is believed to be true or because it is to be used as a basis for argument, but has not been proved. Ocean Waters The territorial marine waters of the State, as defined by California law, to the extent these waters are outside of enclosed bays, estuaries, and coastal lagoons. Discharges to ocean waters are regulated in accordance with the State Water Board’s Californi a Ocean Plan. Percent Effect The value that denotes the difference in response between the test concentration and the control, divided by the mean control response, and multiplied by 100. Permitting Authority The State Water Board or a regional water board that issues a permit, waste discharge requirements, water quality certification, or other authorization for the discharge or proposed discharge of waste. To the extent that the action is delegable, the term “Permitting Authority” can include the Executive Officer or Executive Director. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-7 Persistent Pollutants Persistent pollutants are substances for which degradation or decomposition in the environment is nonexistent or very slow. Point Source Any discernible, confined and discrete conveyance including, but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from whic h pollutants are or may be discharged. This term does not include agricultural stormwater discharges and return flows from irrigated agriculture. Pollutant Defined in section 502(6) of the CWA as “dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt and industrial, municipal, and agricultural waste discharged into water.” Pollutant Minimization Program (PMP) PMP means waste minimization and pollution prevention actions that include, but are not limited to, product substitution, waste stream recycling, alternative waste management methods, and education of the public and businesses. The goal of the PMP shall be to reduce all potential sources of a priority pollutant(s) through pollutant minimization (control) strategies, including pollution prevention measures as appropriate, to maintain the effluent concentration at or below the water quality-based effluent limitation. Pollution prevention measures may be particularly appropriate for persistent bioaccumulative priority pollutants where there is evidence that beneficial uses are being impacted. The Central Coast Water Board may consider cost effectiveness when establishing the requirements of a PMP. The completion and implementation of a Pollution Prevention Plan, if required pursuant to California Water Code section 13263.3(d), shall be considered to fulfill the PMP requirements. Pollution Prevention Pollution Prevention means any action that causes a net reduction in the use or generation of a hazardous substance or other pollutant that is discharged into water and includes, but is not limited to, input change, operational improvement, production process change, and product reformulation (as defined in California Water Code section 13263.3). Pollution prevention does not include actions that merely shift a pollutant in wastewater from one environmental medium to another environmental medium, unless clear environmental benefits of such an approach are identified to the satisfaction of the State Water Resources Control Board (State Water Board) or California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board). Publicly Owned Treatment Works (POTW) Facilities owned by a state or municipality that store, treat, recycle, and reclaim municipal sewage or industrial wastes of a liquid nature. Similar facilities that are privately, instead of publicly owned, are included in this definition for purposes of section III of the Toxicity Provisions. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-8 Reasonable Potential A designation used for a waste discharge that is projected or calculated to cause or contribute to an instream excursion above a water quality standard. Regulatory Management Decision (RMD) The decision that represents the maximum allowable error rates and thresholds for toxicity and non-toxicity that would result in an acceptable risk to aquatic life. Replicates Two or more independent organism exposures of the same treatment (i.e., effluent concentration) within a toxicity test. Replicates are typically conducted with separate test chambers and test organisms, each having the same effluent concentration. Reporting Level (RL) The RL is the ML (and its associated analytical method) chosen by the Discharger for reporting and compliance determination from the MLs included in this Order, including an additional factor if applicable as discussed herein. The MLs included in this Orde r correspond to approved analytical methods for reporting a sample result that are selected by the Central Coast Water Board either from Appendix 4 of the State Implementation Policy (SIP) in accordance with section 2.4.2 of the SIP or established in accordance with section 2.4.3 of the SIP. The ML is based on the proper application of method-based analytical procedures for sample preparation and the absence of any matrix interferences. Other factors may be applied to the ML depending o n the specific sample preparation steps employed. For example, the treatment typically applied in cases where there are matrix-effects is to dilute the sample or sample aliquot by a factor of ten. In such cases, this additional factor must be applied to th e ML in the computation of the RL. Response A measured biological effect (e.g., survival, reproduction, growth) as a result of exposure to a stimulus. Routine Monitoring Required monitoring that occurs during a permit term. Source of Drinking Water Any water designated as municipal or domestic supply (MUN) in a Central Coast Water Board Water Quality Control Plan for the Central Coastal Basin (Basin Plan). Species Sensitivity Screening An analysis to determine the single most sensitive species from an array of test species to be used in a single species laboratory test series. Standard Deviation (σ) Standard Deviation is a measure of variability that is calculated as follows: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-9 where: x is the observed value; µ is the arithmetic mean of the observed values; and n is the number of samples. Stormwater As defined at 40 C.F.R. section 122.26(b)(13) (Nov. 16, 1990) which states, ‘Storm water means storm water runoff, snow melt runoff, and surface runoff and drainage.” Test of Significant Toxicity (TST) A statistical approach used to analyze aquatic toxicity test data, as described in section IV.B.1.c of the Toxicity Provisions. Toxicity Identification Evaluation (TIE) Techniques used to identity the unexplained cause(s) of toxic event. A TIE involves selectively removing classes of chemicals through a series of sample manipulations, effectively reducing complex mixtures of chemicals in natural waters to simple components for analysis. Following each manipulation, the toxicity sample is assessed to see whether the toxicant class removed was responsible for the toxicity. Toxicity Reduction Evaluation (TRE) TRE is a study conducted in a step-wise process designed to identify the causative agents of effluent or ambient toxicity, isolate the sources of toxicity, evaluate the effectiveness of toxicity control options, and then confirm the reduction in toxicity. The first steps of the TRE consist of the collection of data relevant to the toxicity, including additional toxicity testing, and an evaluation of facility operations and maintenance practices, and best management practices. A Toxicity Identification Evaluation (TIE) may be required as part of the TRE, if appropriate. (A TIE is a set of procedures to identify the specific chemical(s) responsible for toxicity. These procedures are performed in three phases (characterization, identification, and confirmation) using aquatic organism toxicity tests.) Toxicity Provisions Refers to State Policy for Water Quality Control: Toxicity Provisions (adopted in 2020 and revised in 2021) of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California . CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT B-MAP B-1 B. ATTACHMENT B – MAP CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-1 C. ATTACHMENT C – FLOW SCHEMATIC CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-2 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-1 D. ATTACHMENT D – STANDARD PROVISIONS 1. STANDARD PROVISIONS – PERMIT COMPLIANCE 1.1. Duty to Comply 1.1.1. The Discharger must comply with all terms, requirements, and conditions of this Order. Any noncompliance constitutes a violation of the Clean Water Act (CWA) and the California Water Code (Water Code) and is grounds for enforcement action; permit termination, revocation and reissuance, or modification; denial of a permit renewal application; or a combination thereof. (40 Code of Federal Regulations (C.F.R.) 122.41(a); Water Code sections 13261, 13263, 13265, 13268, 13000, 13001, 13304, 13350, 13385.) 1.1.2. The Discharger shall comply with effluent standards or prohibitions established under Section 307(a) of the CWA for toxic pollutants within the time provided in the regulations that establish these standards or prohibitions, even if this Order has not yet been modified to incorporate the requirement. (40 C.F.R. 122.41(a)(1).) 1.2. Need to Halt or Reduce Activity Not a Defense It shall not be a defense for a Discharger in an enforcement action that it would have been necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this Order. (40 C.F.R. 122.41(c).) 1.3. Duty to Mitigate The Discharger shall take all reasonable steps to minimize or prevent any discharge in violation of this Order that has a reasonable likelihood of adversely affecting human health or the environment. (40 C.F.R. 122.41(d).) 1.4. Proper Operation and Maintenance The Discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the Discharger to achieve compliance with the conditions of this Order. Proper operation and maintenance also include adequate laboratory controls and appropriate quality assurance procedures. This provision requires the operation of backup or auxiliary facilities or similar systems that are installed by a Discharger only when necessary to achieve compliance with the conditions of this Order. (40 C.F.R. 122.41(e).) 1.5. Property Rights 1.5.1. This Order does not convey any property rights of any sort or any exclusive privileges. (40 C.F.R. 122.41(g).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-2 1.5.2. The issuance of this Order does not authorize any injury to persons or property or invasion of other private rights, or any infringement of state or local law or regulations. (40 C.F.R. 122.5(c).) 1.6. Inspection and Entry The Discharger shall allow the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board), State Water Resources Control Board (State Water Board), United States Environmental Protection Agency (U.S. EPA), and/or their authorized representatives (including an authorized contractor acting as their representative), upon the presentation of credentials and other documents, as may be required by law, to (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i); Water Code sections 13267, 13383): 1.6.1. Enter upon the Discharger's premises where a regulated facility or activity is located or conducted, or where records are kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(i); 40 C.F.R. 122.41(i)(1); Water Code sections 13267, 13383); 1.6.2. Have access to and copy, at reasonable times, any records that must be kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(2); Water Code sections 13267, 13383); 1.6.3. Inspect and photograph, at reasonable times, any facilities, equipment (including monitoring and control equipment), practices, or operations regulated or required under this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(3); Water Code sections 13267, 13383); and 1.6.4. Sample or monitor, at reasonable times, for the purposes of assuring Order compliance or as otherwise authorized by the CWA or the Water Code, any substances or parameters at any location. (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i)(4); Water Code sections 13267, 13383.) 1.7. Bypass 1.7.1. Definitions 1.7.1.1. “Bypass” means the intentional diversion of waste streams from any portion of a treatment facility. (40 C.F.R. 122.41(m)(1)(i).) 1.7.1.2. “Severe property damage” means substantial physical damage to property, damage to the treatment facilities, which causes them to become inoperable, or substantial and permanent loss of natural resources that can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production. (40 C.F.R. 122.41(m)(1)(ii).) 1.7.2. Bypass not exceeding limitations. The Discharger may allow any bypass to occur which does not cause exceedances of effluent limitations, but only if it is for essential maintenance to assure efficient operation. These bypasses are not subject to the provisions listed in Standard Provisions – Permit Compliance 1.7.3, 1.7.4, and 1.7.5 below. (40 C.F.R. 122.41(m)(2).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-3 1.7.3. Prohibition of bypass. Bypass is prohibited, and the Central Coast Water Board may take enforcement action against a Discharger for bypass, unless (40 C.F.R. 122.41(m)(4)(i)): 1.7.3.1. Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage (40 C.F.R. 122.41(m)(4)(i)(A)); 1.7.3.2. There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass that occurred during normal periods of equipment downtime or preventive maintenance (40 C.F.R. 122.41(m)(4)(i)(B)); and 1.7.3.3. The Discharger submitted notice to the Central Coast Water Board as required under Standard Provisions – Permit Compliance 1.7.5 below. (40 C.F.R. 122.41(m)(4)(i)(C).) 1.7.4. The Central Coast Water Board may approve an anticipated bypass, after considering its adverse effects, if the Central Coast Water Board determines that it will meet the three conditions listed in Standard Provisions – Permit Compliance 1.7.3 above. (40 C.F.R. 122.41(m)(4)(ii).) 1.7.5. Notice 1.7.5.1. Anticipated bypass. If the Discharger knows in advance of the need for a bypass, it shall submit prior notice, if possible, at least 10 days before the date of the bypass. The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part127. (40 C.F.R. 122.41(m)(3)(i).) 1.7.5.2. Unanticipated bypass. The Discharger shall submit a notice of an unanticipated bypass as required in Standard Provisions - Reporting 5.5 below (24-hour notice). The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(m)(3)(ii).) 1.8. Upset Upset means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the Discharger. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. (40 C.F.R. 122.41(n)(1).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-4 1.8.1. Effect of an upset. An upset constitutes an affirmative defense to an action brought for noncompliance with such technology-based permit effluent limitations if the requirements of Standard Provisions – Permit Compliance 1.8.2 below are met. No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review. (40 C.F.R. 122.41(n)(2).) 1.8.2 Conditions necessary for a demonstration of upset. A Discharger who wishes to establish the affirmative defense of upset shall demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that (40 C.F.R. 122.41(n)(3)): 1.8.2.1. An upset occurred and that the Discharger can identify the cause(s) of the upset (40 C.F.R. 122.41(n)(3)(i)); 1.8.2.2. The permitted facility was, at the time, being properly operated (40 C.F.R. 122.41(n)(3)(ii)); 1.8.2.3. The Discharger submitted notice of the upset as required in Standard Provisions – Reporting 5.5.2.2 below (24-hour notice) (40 C.F.R. 122.41(n)(3)(iii)); and 1.8.2.4. The Discharger complied with any remedial measures required under Standard Provisions – Permit Compliance 1.3 above. (40 C.F.R. 122.41(n)(3)(iv).) 1.8.3. Burden of proof. In any enforcement proceeding, the Discharger seeking to establish the occurrence of an upset has the burden of proof. (40 C.F.R. 122.41(n)(4).) 2. STANDARD PROVISIONS – PERMIT ACTION 2.1. General This Order may be modified, revoked and reissued, or terminated for cause. The filing of a request by the Discharger for modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not stay any Order condition. (40 C.F.R. 122.41(f).) 2.2. Duty to Reapply If the Discharger wishes to continue an activity regulated by this Order after the expiration date of this Order, the Discharger must apply for and obtain a new permit. (40 C.F.R. 122.41(b).) 2.3. Transfers This Order is not transferable to any person except after notice to the Central Coast Water Board. The Central Coast Water Board may require modification or revocation and reissuance of the Order to change the name of the Discharger and incorporate such other requirements as may be necessary under the CWA and the Water Code. (40 C.F.R. 122.41(l)(3), 122.61.) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-5 3. STANDARD PROVISIONS – MONITORING 3.1. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. (40 C.F.R. 122.41(j)(1).) 3.2. Monitoring must be conducted according to test procedures approved under 40 C.F.R. part 136 for the analyses of pollutants unless another method is required under 40 C.F.R. chapter 1, subchapter N. Monitoring must be conducted according to sufficiently sensitive test methods approved under 40 C.F.R. part 136 for the analysis of pollutants or pollutant parameters or as required under 40 C.F.R. chapter 1, subchapter N. For the purposes of this paragraph, a method is sufficiently sensitive when: 3.2.1. The method minimum level (ML) is at or below the level of the most stringent effluent limitation established in the permit for the measured pollutant or pollutant parameter, and either the method ML is at or below the level of the most stringent applicable water quality criterion for the measured pollutant or pollutant parameter or the method ML is above the applicable water quality criterion but the amount of the pollutant or pollutant parameter in the facility’s discharge is high enough that the method detects and quantifies the level of the pollutant or pollutant parameter in the discharge; or 3.2.2. The method has the lowest ML of the analytical methods approved under 40 C.F.R. part 136 or required under 40 C.F.R. chapter 1, subchapter N for the measured pollutant or pollutant parameter. In the case of pollutants or pollutant parameters for which there are no approved methods under 40 C.F.R. part 136 , or otherwise required under 40 C.F.R. chapter 1, subchapter N, monitoring must be conducted according to a test procedure specified in this Order for such pollutants or pollutant parameters. (40 C.F.R. 122.21(e)(3), 122.41(j)(4), 122.44(i)(1)(iv).) 4. STANDARD PROVISIONS – RECORDS 4.1. The Discharger shall retain records of all monitoring information , including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation, copies of all reports required by this Order, and records of all data used to complete the application for this Order, fo r a period of at least three (3) years from the date of the sample, measurement, report or application. This period may be extended by request of the Central Coast Water Board Executive Officer at any time. (40 C.F.R. 122.41(j)(2).) 4.2. Records of monitoring information shall include: 4.2.1. The date, exact place, and time of sampling or measurements (40 C.F.R. 122.41(j)(3)(i)); 4.2.2. The individual(s) who performed the sampling or measurements (40 C.F.R. 122.41(j)(3)(ii)); 4.2.3. The date(s) analyses were performed (40 C.F.R. 122.41(j)(3)(iii)); CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-6 4.2.4. The individual(s) who performed the analyses (40 C.F.R. 122.41(j)(3)(iv)); 4.2.5. The analytical techniques or methods used (40 C.F.R. 122.41(j)(3)(v)); and 4.2.6. The results of such analyses. (40 C.F.R. 122.41(j)(3)(vi).) 4.3. Claims of confidentiality for the following information will be denied (40 C.F.R. 122.7(b)): 4.3.1. The name and address of any permit applicant or Discharger (40 C.F.R. 122.7(b)(1)); and 4.3.2. Permit applications and included attachments, permits, and effluent data. (40 C.F.R. 122.7(b)(2).) 5. STANDARD PROVISIONS – REPORTING 5.1. Duty to Provide Information The Discharger shall furnish to the Central Coast Water Board, State Water Board, or U.S. EPA within a reasonable time, any information which the Central Coast Water Board, State Water Board, or U.S. EPA may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this Order or to determine compliance with this Order. Upon request, the Discharger shall also furnish to the Central Coast Water Board, State Water Board, or U.S. EPA copies of records required to be kept by this Order. (40 C.F.R. 122.41(h); Water Code sections 13267, 13383.) 5.2. Signatory and Certification Requirements 5.2.1. All applications, reports, or information submitted to the Central Coast Water Board, State Water Board, and/or U.S. EPA shall be signed and certified in accordance with Standard Provisions – Reporting 5.2.2, 5.2.3, 5.2.4, 5.2.5, and 5.2.6 below. (40 C.F.R. 122.41(k).) 5.2.2. All permit applications shall be signed by a responsible corporate officer. For the purpose of this section, a responsible corporate officer means: (i) A president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy- or decision- making functions for the corporation, or (ii) the manager of one or more manufacturing, production, or operating facilities, provided, the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmenta l compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures. (40 C.F.R. 122.22(a)(1).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-7 5.2.3. All reports required by this Order and other information requested by the Central Coast Water Board, State Water Board, or U.S. EPA shall be signed by a person described in Standard Provisions – Reporting 5.2.2 above, or by a duly authorized representative of that person. A person is a duly authorized representative only if: 5.2.3.1. The authorization is made in writing by a person described in Standard Provisions – Reporting 5.2.2 above (40 C.F.R. 122.22(b)(1)); 5.2.3.2. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the company. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.) (40 C.F.R. 122.22(b)(2)); and 5.2.3.3. The written authorization is submitted to the Central Coast Water Board and State Water Board. (40 C.F.R. 122.22(b)(3).) 5.2.4. If an authorization under Standard Provisions – Reporting 5.2.3 above is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of Standard Provisions – Reporting 5.2.3 above must be submitted to the Central Coast Water Board and State Water Board prior to or together with any reports, information, or applications, to be signed by an authorized representative. (40 C.F.R. 122.22(c).) 5.2.5. Any person signing a document under Standard Provisions – Reporting 5.2.2 or 5.2.3 above shall make the following certification: “I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.” (40 C.F.R. 122.22(d).) 5.2.6. Any person providing the electronic signature for documents described in Standard Provisions – 5.2.1, 5.2.2, or 5.2.3 that are submitted electronically shall meet all relevant requirements of Standard Provisions – Reporting 5.2, and shall ensure that all relevant requirements of 40 C.F.R. part 3 (Cross-Media Electronic Reporting) and 40 C.F.R. part 127 (NPDES Electronic Reporting Requirements) are met for that submission. (40 C.F.R 122.22(e).) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-8 5.3. Monitoring Reports 5.3.1. Monitoring results shall be reported at the intervals specified in the Monitoring and Reporting Program (Attachment E) in this Order. (40 C.F.R. 122.41(l)(4).) 5.3.2. Monitoring results must be reported on a Discharge Monitoring Report (DMR) form or forms provided or specified by the Central Coast Water Board or State Water Board. All reports and forms must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 and comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(l)(4)(i).) 5.3.3. If the Discharger monitors any pollutant more frequently than required by this Order using test procedures approved under 40 C.F.R. part 136, or another method required for an industry-specific waste stream under 40 C.F.R. chapter 1, subchapter N, the results of such monitoring shall be included in the calculation and reporting of the data submitted in the DMR or reporting form specified by the Central Coast Water Board or State Water Board. (40 C.F.R. 122.41(l)(4)(ii).) 5.3.4. Calculations for all limitations, which require averaging of measurements, shall utilize an arithmetic mean unless otherwise specified in this Order. (40 C.F.R. 122.41(l)(4)(iii).) 5.4. Compliance Schedules Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule of this Order, shall be submitted no later than 14 days following each schedule date. (40 C.F.R. 122.41(l)(5).) 5.5. Twenty-Four Hour Reporting 5.5.1. The Discharger shall report any noncompliance which may endanger health or the environment. Any information shall be provided orally within 24 hours from the time the Discharger becomes aware of the circumstances. A report shall also be provided within five (5) days of the time the Discharger becomes aware of the circumstances. The report shall contain a description of the noncompliance and its cause; the period of noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports must include the data described above (with the exception of time of discovery) as well as the type of event (i.e., combined sewer overflow, sanitary sewer overflow, or bypass event), type of overflow structure (e.g., manhole, combined sewer overflow outfall), discharge volume untreated by the treatment works treating domestic sewage, types of human health and environmental impacts of the event, and whether the noncompliance was related to wet weather. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-9 As of December 21, 2023, all reports related to combined sewer overflows, sanitary sewer overflows, or bypass events must be submitted to the Central Coast Water Board and must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 The reports shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(6)(i).) 5.5.2. The following shall be included as information that must be reported within 24 hours: 5.5.2.1. Any unanticipated bypass that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(A).) 5.5.2.2. Any upset that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.5.3. The Central Coast Water Board may waive the above required written report on a case-by-case basis if an oral report has been received within 24 hours. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.6. Planned Changes The Discharger shall give notice to the Central Coast Water Board as soon as possible of any planned physical alterations or additions to the permitted facility. Notice is required under this provision only when (40 C.F.R. 122.41(l)(1)): 5.6.1. The alteration or addition to a permitted facility may meet one of the criteria for determining whether a facility is a new source in section 122.29(b) (40 C.F.R. 122.41(l)(1)(i)); or 5.6.2. The alteration or addition could significantly change the nature or increase the quantity of pollutants discharged. This notification applies to pollutants that are not subject to effluent limitations in this Order. (40 C.F.R. 122.41(l)(1)(ii).); or 5.7. Anticipated Noncompliance The Discharger shall give advance notice to the Central Coast Water Board of any planned changes in the permitted facility or activity that may result in noncompliance with this Order’s requirements. (40 C.F.R. 122.41(l)(2).) 5.8. Other Noncompliance The Discharger shall report all instances of noncompliance not reported under Standard Provisions – Reporting 5.3, 5.4, and 5.5 above at the time monitoring reports are submitted. The reports shall contain the information listed in Standard Provision – Reporting 5.5 above. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports shall contain the information described in Standard Provision – Reporting 5.5 and the applicable required data in appendix A to 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-10 related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(7).) 5.9 Other Information When the Discharger becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or in any report to the Central Coast Water Board, State Water Board, or U.S. EPA, the Discharger shall promptly submit such facts or information. (40 C.F.R. 122.41(l)(8).) 5.10. Initial Recipient for Electronic Reporting Data The owner, operator, or the duly authorized representative is required to electronically submit NPDES information specified in appendix A to 40 C.F.R. part 127 to the initial recipient defined in 40 C.F.R. section 127.2(b). U.S. EPA will identify and publish the list of initial recipients on its website and in the Federal Register, by state and by NPDES data group [see 40 C.F.R. 127.2(c)]. U.S. EPA will update and maintain this listing. (40 C.F.R. 122.41(l)(9).) 6. STANDARD PROVISIONS – ENFORCEMENT 6.1. The Central Coast Water Board is authorized to enforce the terms of this permit under several provisions of the Water Code, including, but not limited to, sections 13268, 13350, 13385, 13386, and 13387. 7. ADDITIONAL PROVISIONS – NOTIFICATION LEVELS 7.1. Non-Municipal Facilities Existing manufacturing, commercial, mining, and silvicultural Dischargers shall notify the Central Coast Water Board as soon as they know or have reason to believe (40 C.F.R. 122.42(a)): 7.1.1. That any activity has occurred or will occur that would result in the discharge, on a routine or frequent basis, of any toxic pollutant that is not limited in this Order, if that discharge will exceed the highest of the following "notification levels" (40 C.F.R. 122.42(a)(1)): 7.1.1.1. 100 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(1)(i)); 7.1.1.2. 200 μg/L for acrolein and acrylonitrile; 500 μg/L for 2,4 dinitrophenol and 2-methyl 4,6 dinitrophenol; and 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(1)(ii)); 7.1.1.3. Five (5) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(1)(iii)); or 7.1.1.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(1)(iv).) 7.1.2. That any activity has occurred or will occur that would result in the discharge, on a non-routine or infrequent basis, of any toxic pollutant that is not limited in this CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-11 Order, if that discharge will exceed the highest of the following “notification levels" (40 C.F.R. 122.42(a)(2)): 7.1.2.1. 500 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(2)(i)); 7.1.2.2. 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(2)(ii)); 7.1.2.3. Ten (10) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(2)(iii)); or 7.1.2.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(2)(iv).) 7.2 Publicly Owned Treatment Works (POTWs) All POTWs shall provide adequate notice to the Central Coast Water Board of the following (40 C.F.R. 122.42(b)): 7.2.1. Any new introduction of pollutants into the POTW from an indirect discharger that would be subject to sections 301 or 306 of the CWA if it were directly discharging those pollutants (40 C.F.R. 122.42(b)(1)); and 7.2.2. Any substantial change in the volume or character of pollutants being introduced into that POTW by a source introducing pollutants into the POTW at the time of adoption of the Order. (40 C.F.R. 122.42(b)(2).) 7.2.3. Adequate notice shall include information on the quality and quantity of effluent introduced into the POTW as well as any anticipated impact of the change on the quantity or quality of effluent to be discharged from the POTW. (40 C.F.R. 122.42(b)(3).) 8. CENTRAL COAST WATER BOARD STANDARD PROVISIONS 8.1. Central Coast Standard Provision – Prohibitions 8.1.1. Introduction of “incompatible wastes” to the treatment system is prohibited. 8.1.2. Discharge of high-level radiological waste and of radiological, chemical, and biological warfare agents is prohibited. 8.1.3. Discharge of “toxic pollutants” in violation of effluent standards and prohibitions established under section 307(a) of the CWA is prohibited. 8.1.4. Discharge of sludge, sludge digester or thickener supernatant, and sludge drying bed leachate to drainageways, surface waters, or the ocean is prohibited. 8.1.5. Introduction of pollutants into the collection, treatment, or disposal system by and “indirect discharger” that: 8.1.5.1. Inhibit or disrupt the treatment process, system operation, or the eventual use or disposal of sludge; or, 8.1.5.2. Flow through the system to the receiving water untreated; and, 8.1.5.3. Cause or “significantly contribute” to a violation of any requirement of this Order, is prohibited. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-12 8.1.6. Introduction of “pollutant free” wastewater to the collection, treatment, and disposal system in amounts that threaten compliance with this order is prohibited. 8.2. Central Coast Standard Provisions 8.2.1. Collection, treatment, and discharge of waste shall not create a nuisance or pollution, as defined by Water Code section 13050. 8.2.2. All facilities used for transport or treatment of wastes shall be adequately protected from inundation and washout as the result of a 100-year frequency flood. 8.2.3. Operation of collection, treatment, and disposal systems shall be in a manner that precludes public contact with wastewater. 8.2.4. Collected screenings, sludges, and other solids removed from liquid wastes shall be disposed in a manner approved by the Executive Officer. 8.2.5. Publicly owned wastewater treatment plans shall be supervised and operated by persons possessing certificates of appropriate grade pursuant to title 23 of the California Administrative Code. 8.2.6. After notice and opportunity for a hearing, this order may be terminated for cause, including, but not limited to: 8.2.6.1. Violation of any term or condition contained in this order; 8.2.6.2. Obtaining this order by misrepresentation, or by failure to disclose fully all relevant facts; 8.2.6.3. A change in any condition or endangerment to human health or environment that requires a temporary or permanent reduction or elimination of the authorized discharge; and, 8.2.6.4. A substantial change in character, location, or volume of the discharge. 8.2.7. Provisions of this permit are severable. If any provision of the permit is found invalid, the remainder of the permit shall not be affected. 8.2.8. After notice and opportunity for hearing, this order may be modified or revoked and reissued for cause, including: 8.2.8.1. Promulgation of a new or revised effluent standard or limitation; 8.2.8.2. A material change in character, location, or volume of the discharge; 8.2.8.3. Access to new information that affects the germs of the permit, including applicable schedules; 8.2.8.4. Correction of technical mistakes or mistaken interpretations of law; and, 8.2.8.5. Other causes set forth under Sub -part D of 40 C.F.R. part 122. 8.2.9. Safeguards shall be provided to ensure maximal compliance with all terms and conditions of this permit. Safeguards shall include preventative and contingency plans and may also include alternative power sources, stand-by generators, retention capacity, operative procedures, or other precautions. Preventative and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-13 contingency plans for controlling and minimizing the effect of accidental discharges shall: 8.2.9.1. Identify possible situations that could cause “upset,” “overflow,” or “bypass,” or other noncompliance. (Loading and storage areas, power outage, waste treatment unit outage, and failure of process equipment, tanks and pipes should be considered). 8.2.9.2. Evaluate the effectiveness of present facilities and procedures and describe procedures and steps to minimize or correct any adverse environmental impact resulting from noncompliance with the permit. 8.2.10. Physical Facilities shall be designed and constructed according to accepted engineering practice and shall be capable of full compliance with this order when properly operated and maintained. Proper operation and maintenance shall be described in an Operation and Maintenance Manual. Facilities shall be accessible during the wet-weather season. 8.2.11. The discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) that are installed or used by the discharger to achieve compliance with the conditions of this order. Electrical and mechanical equipment shall be maintained in accordance with appropriate practices and standards, such as NFPA 70B, Recommended Practice for Electrical Equipment Maintenance; NFPA 70E, Standard for Electrical Safety in the Workplace; ANSI/NETA MTS Standard for Maintenance: Testing Specifications for Electrical Power Equipment and Systems, or procedures established by insurance companies or industry resources. 8.2.12. If the discharger’s facilities are equipped with SCADA or other systems that implement wireless, remote operation, the discharger should implement appropriate safeguards against unauthorized access to the wireless systems. Standards such as NIST SP 800-53, Recommended Security Controls for Federal Information Systems, can provide guidance. 8.2.13. Production and use of reclaimed water is subject to the approval of the Central Coast Water Board. Production and use of reclaimed water shall be in conformance with recycling criteria established in chapter 3, title 22, of the California Administrative Code and chapter 7, division 7, of the Water Code. An engineering report pursuant to section 60323, title 22, of the California Administrative Code is required and a waiver or water recycling requirements from the Central Coast Water Board is required before reclaimed water is supplied for any use, or to any user, not specifically identified and approved either in this Order or another order issued by the Central Coast Water Board. 8.3. Central Coast Standard Provisions – General Monitoring Requirements 8.3.1. If results of monitoring a pollutant appear to violate effluent limitations based on a weekly, monthly, 30-day, or six-month period, but compliance or non-compliance cannot be validated because sampling is too infrequent, the frequency of sampling shall be increased to validate the test within the next monitoring period. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-14 The increased frequency shall be maintained until the Executive Officer agrees the original monitoring frequency may be resumed. For example, if copper is monitored annually and results exceed the six -month median numerical effluent limitation in the permit, monitoring of copper must be increased to a frequency of at least once every two months (Central Coast Standard Provisions – Definitions 1.7.13.). If suspended solids are monitored weekly and results exceed the weekly average numerical limit in the permit, monitoring of suspended solids must be increased to at least four (4) samples every week (Central Coast Standard Provisions – Definitions 1.7.14.). 8.3.2. Water quality analyses performed in order to monitor compliance with this permit shall be by a laboratory certified by the Division of Drinking Water for the constituent(s) being analyzed. Bioassay(s) performed in order to monitor compliance with this permit shall be in accord with guidelines approved by the State Water Board and the California Department of Fish and Wildlife. If the laboratory used or proposed for use by the discharger is not certified by the Division of Drinking Water or, where appropriate, the Department of Fish and Wildlife due to restrictions in the State's laboratory certification program, the discharger shall be considered in compliance with this provision provided: 8.3.2.1. Data results remain consistent with results of samples analyzed by the Central Coast Water Board; 8.3.2.2. A quality assurance program is used at the laboratory, including a manual containing steps followed in this program that is available for inspections by the staff of the Central Coast Water Board; and, 8.3.2.3. Certification is pursued in good faith and obtained as soon as possible after the program is reinstated. 8.3.3. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. Samples shall be taken during periods of peak loading conditions. Influent samples shall be samples collected from the combined flows of all incoming wastes, excluding recycled wastes. Effluent samples shall be samples collected downstream of the last treatment unit and tributary flow and upstream of any mixing with receiving waters. 8.3.4. All monitoring instruments and devices used by the discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. 8.4. Central Coast Standard Provisions – General Reporting Requirements 8.4.1. Reports of marine monitoring surveys conducted to meet receiving water monitoring requirements of the Monitoring and Reporting Program shall include at least the following information: 8.4.1.1. A description of climatic and receiving water characteristics at the time of sampling (weather observations, floating debris, discoloration, wind speed and direction, swell or wave action, time of sampling, tide height, etc.). CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-15 8.4.1.2. A description of sampling stations, including differences unique to each station (e.g., station location, grain size, rocks, shell litter, calcareous worm tubes, evident life, etc.). 8.4.1.3. A description of the sampling procedures and preservation sequence used in the survey. 8.4.1.4. A description of the exact method used for laboratory analysis. In general, analysis shall be conducted according to Central Coast Standard Provisions – 8.3.1 above, and Federal Standard Provision – Monitoring 3.2. However, variations in procedure are acceptable to accommodate the special requirements of sediment analysis. All such variations must be reported with the test results. 8.4.1.5. A brief discussion of the results of the survey. The discussion shall compare data from the control station with data from the outfall stations. All tabulations and computations shall be explained. 8.4.2. Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule shall be submitted within 14 days following each scheduled date unless otherwise specified within the permit. If reporting noncompliance, the report shall include a description of the reason, a description and schedule of tasks necessary to achieve compliance, and an estimated date for achieving full compliance. A second report shall be submitted within 14 days of full compliance. 8.4.3. The Discharger shall file a Report of Waste Discharge or secure a waiver from the Executive Officer at least 180 days before making any material change or proposed change in the character, location, or plume of the discharge. 8.4.4. Within 120 days after the Discharger discovers, or is notified by the Central Coast Water Board, that monthly average daily flow will or may reach design capacity of waste treatment and/or disposal facilities within four (4) years, the Discharger shall file a written report with the Central Coast Water Board. The report shall include: 8.4.4.1. The best estimate of when the monthly average daily dry weather flow rate will equal or exceed design capacity; and, 8.4.4.2. A schedule for studies, design, and other steps needed to provide additional capacity for waste treatment and/or disposal facilities before the waste flow rate equals the capacity of present units. In addition to complying with Federal Standard Provision – Reporting 5.2, the required technical report shall be prepared with public participation and reviewed, approved and jointly submitted by all planning and building departments having jurisdiction in the area served by the waste collection, treatment, or disposal facilities. 8.4.5. All Dischargers shall submit reports electronically to the: California Regional Water Quality Control Board Central Coast Region CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-16 centralcoast@waterboards.ca.gov 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 In addition, Dischargers with designated major discharges shall submit a copy of each document to: Regional Administrator U.S. EPA, Region 9 Attention: CWA Standards and Permits Office (WTR-5) 75 Hawthorne Street San Francisco, California 94105 8.4.6. Transfer of control or ownership of a waste discharge facility must be preceded by a notice to the Central Coast Water Board at least 30 days in advance of the proposed transfer date. The notice must include a written agreement between the existing Discharger and proposed Discharger containing specific date for transfer of responsibility, coverage, and liability between them. Whether a permit may be transferred without modification or revocation and reissuance is at the discretion of the Board. If permit modification or revocation and reissuance is necessary, transfer may be delayed 180 days after the Central Coast Water Board's receipt of a complete permit application. Please also see Federal Standard Provision – Permit Action 2.3. 8.4.7. Except for data determined to be confidential under CWA section 308 (excludes effluent data and permit applications), all reports prepared in accordance with this permit shall be available for public inspection at the office of the Central Coast Water Board or Regional Administrator of U.S. EPA. Please also see Federal Standard Provision – Records 4.3. 8.4.8. By February 1st of each year, the discharger shall submit an annual report to the Central Coast Water Board. The report shall contain the following: 8.4.8.1. Both tabular and graphical summaries of the monitoring data obtained during the previous year. 8.4.8.2. A discussion of the previous year’s compliance record and corrective actions taken, or which may be needed, to bring the discharger into full compliance. 8.4.8.3. An evaluation of wastewater flows with projected flow rate increases over time and the estimated date when flows will reach facility capacity. 8.4.8.4. A discussion of operator certification and a list of current operating personnel and their grades of certification. 8.4.8.5. The date of the facility’s Operation and Maintenance Manual (including contingency plans as described in Provision 8.2.9), the date the manual was last reviewed, and whether the manual is complete and valid for the current facility. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-17 8.4.8.6. A discussion of the laboratories used by the discharger to monitor compliance with effluent limits and a summary of performance relative to section 8.3, General Monitoring Requirements. 8.4.8.7. If the facility treats industrial or domestic wastewater and there is no provision for periodic sludge monitoring in the Monitoring and Reporting Program, the report shall include a summary of sludge quantities, analyses of its chemical and moisture content, and its ultimate destination. 8.4.8.8. If appropriate, the report shall also evaluate the effectiveness of the local source control or pretreatment program using the State Water Board's "Guidelines for Determining the Effectiveness of Local Pretreatment Program." 8.5. Central Coast Standard Provisions – General Pretreatment Provisions 8.5.1. Discharge of pollutants by "indirect dischargers” in specific industrial sub- categories (appendix C, 40 C.F.R. part 403), where categorical pretreatment standards have been established, or are to be established, (according to 40 C.F.R. chapter 1, subchapter N), shall comply with the appropriate pretreatment standards: 8.5.1.1. By the date specified therein; 8.5.1.2. Within three (3) years of the effective date specified therein, but in no case later than July 1, 1984; or, 8.5.1.3. If a new indirect discharger, upon commencement of discharge. 8.6. Central Coast Standard Provision – Enforcement 8.6.1. Any person failing to file a Report of Waste Discharge or other report as required by this permit shall be subject to a civil penalty not to exceed $5,000 per day. 8.6.2. Upon reduction, loss, or failure of the treatment facility, the Discharger shall, to the extent necessary to maintain compliance with this permit, control production or all discharges, or both, until the facility is restored or an alternative method of treatment is provided. 8.7. Central Coast Standard Provisions – Definitions (Not otherwise included in Attachment A to this Order) 8.7.1. A “composite sample" is a combination of no fewer than eight (8) individual samples obtained at equal time intervals (usually hourly) over the specified sampling (composite) period. The volume of each individual sample is proportional to the flow rate at the time of sampling. The period shall be specified in the Monitoring and Reporting Program ordered by the Executive Officer. 8.7.2. “Daily Maximum” limit means the maximum acceptable concentration or mass emission rate of a pollutant measured during a calendar day or during any 24 - hour period reasonably representative of the calendar day for purposes of sampling. It is normally compared with results based on "composite samples” except for ammonia, total chlorine, phenolic compounds, and toxicity CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-18 concentration. For all exceptions, comparisons will be made with results from a “grab sample”. 8.7.3. “Discharger", as used herein, means, as appropriate: (1) the Discharger, (2) the local sewering entity (when the collection system is not owned and operated by the Discharger), or (3) "indirect discharger" (where "Discharger" appears in the same paragraph as "indirect discharger”, it refers to the discharger.) 8.7.4. “Duly Authorized Representative" is one where: 8.7.4.1. The authorization is made in writing by a person described in the signatory paragraph of Federal Standard Provision 5.2.; 8.7.4.2. The authorization specifies either an individual or the occupant of a position having either responsibility for the overall operation of the regulated facility, such as the plant manager, or overall responsibility for environmental matters of the company; and, 8.7.4.3. The written authorization was submitted to the Central Coast Water Board. 8.7.5. A "grab sample" is defined as any individual sample collected in less than 15 minutes. "Grab samples” shall be collected during peak loading conditions, which may or may not be during hydraulic peaks. It is used primarily in determining compliance with the daily maximum limits identified in Central Coast Standard Provision – Provision 8.7.2. and instantaneous maximum limits. 8.7.6. "Hazardous substance” means any substance designated under 40 C.F.R. part 116 pursuant to section 311 of the CWA. 8.7.7. "Incompatible wastes” are: 8.7.7.1. Wastes which create a fire or explosion hazard in the treatment works; 8.7.7.2. Wastes which will cause corrosive structural damage to treatment works, but in no case wastes with a pH lower than 5.0 unless the works is specifically designed to accommodate such wastes; 8.7.7.3. Solid or viscous wastes in amounts which cause obstruction to flow in sewers, or which cause other interference with proper operation of treatment works; 8.7.7.4. Any waste, including oxygen demanding pollutants (BOD, etc.), released in such volume or strength as to cause inhibition or disruption in the treatment works and subsequent treatment process upset and loss of treatment efficiency; and, 8.7.7.5. Heat in amounts that inhibit or disrupt biological activity in the treatment works or that raise influent temperatures above 40°C (104°F) unless the treatment works is designed to accommodate such heat. 8.7.8. "Indirect Discharger” means a non-domestic discharger introducing pollutants into a publicly owned treatment and disposal system. 8.7.9. "Log Mean” is the geometric mean. Used for determining compliance of fecal or total coliform populations, it is calculated with the following equation: Log Mean = (C1 x C2 x...x Cn)1/n, CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-19 in which “n" is the number of days samples were analyzed during the period and any "C" is the concentration of bacteria (MPN/100 mL) found on each day of sampling. "n” should be five or more. 8.7.10. “Mass emission rate" is a daily rate defined by the following equations: mass emission rate (lbs/day) = 8.34 x Q x C; and, mass emission rate (kg/day) = 3.79 x Q x C, where “C" (in mg/L) is the measured daily constituent concentration or the average of measured daily constituent concentrations and “Q” (in MGD) is the measured daily flowrate or the average of measured daily flow rates over the period of interest. 8.7.11. The "Maximum Allowable Mass Emission Rate," whether for a month, week, day, or six-month period, is a daily rate determined with the formulas in paragraph 8.7.10, above, using the effluent concentration limit specified in the permit for the period and the average of measured daily flows (up to the allowable flow) over the period. 8.7.12. “Maximum Allowable Six-Month Median Mass Emission Rate" is a daily rate determined with the formulas in Central Coast Standard Provision – Provision 8.7.10, above, using the "six-month Median" effluent limit specified in the permit, and the average of measured daily flows (up to the allowable flow) over a 180-day period. 8.7.13. "Median" is the value below which half the samples (ranked progressively by increasing value) fall. It may be considered the middle value, or the average of two middle values. 8.7.14. "Monthly Average" (or "Weekly Average”, as the case may be) is the arithmetic mean of daily concentrations or of daily mass emission rates over the specified 30-day (or 7-day) period. Average = (X1 + X2 + ... + Xn) / n in which “n" is the number of days samples were analyzed during the period and “X" is either the constituent concentration (mg/l) or mass emission rate (kg/day or lbs/day) for each sampled day. “n" should be four or greater. 8.7.15. "Municipality" means a city, town, borough, county, district, association, or other public body created by or under State law and having jurisdiction over disposal of sewage, industrial waste, or other waste. 8.7.16. "Overflow" means the intentional or unintentional diversion of flow from the collection and transport systems, including pumping facilities. 8.7.17. "Pollutant-free wastewater" means inflow and infiltration, stormwaters, and cooling waters and condensates which are essentially free of pollutants. 8.7.18. "Primary Industry Category" means any industry category listed in 40 C.F.R. part 122, Appendix A. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-20 8.7.19. "Removal Efficiency" is the ratio of pollutants removed by the treatment unit to pollutants entering the treatment unit. Removal efficiencies of a treatment plant shall be determined using “Monthly averages" of pollutant concentrations (C, in mg/l) of influent and effluent samples collected about the same time and the following equation (or its equivalent): 8.7.20. "Severe property damage" means substantial physical damage to property, damage to treatment facilities which causes them to become inoperable, or substantial and permanent loss to natural resources which can reasonably be expected to occur in the absence of a "bypass”. It does not mean economic loss caused by delays in production. 8.7.21. "Sludge" means the solids, residues, and precipitates separated from, or created in, wastewater by the unit processes of a treatment system. 8.7.22. To "significantly contribute" to a permit violation means an "indirect discharger" must: 8.7.22.1. Discharge a daily pollutant loading in excess of that allowed by contract with the Discharger or by Federal, State, or Local law; 8.7.22.2. Discharge wastewater which substantially differs in nature or constituents from its average discharge; 8.7.22.3. Discharge pollutants, either alone or in conjunction with discharges from other sources, which results in a permit violation or prevents sewage sludge use or disposal; or 8.7.22.4. Discharge pollutants, either alone or in conjunction with pollutants from other sources that increase the magnitude or duration of permit violations. 8.7.23. "Toxic Pollutant" means any pollutant listed as toxic under Section 307 (a) (1) of the CWA or under 40 C.F.R. part 122, Appendix D. Violation of maximum daily discharge limitations are subject to 24-hour reporting (Federal Standard Provisions 5.5.). 8.7.24. “Zone of Initial Dilution" means the region surrounding or adjacent to the end of an outfall pipe or diffuser ports whose boundaries are defined through calculation of a plume model verified by the State Water Board. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-1 E. ATTACHMENT E – MONITORING AND REPORTING PROGRAM TABLE OF CONTENTS 1. GENERAL MONITORING PROVISIONS .................................................................E-2 2. MONITORING LOCATIONS ....................................................................................E-3 3. INFLUENT MONITORING REQUIREMENTS ..........................................................E-5 3.1. Monitoring Location INF-001 .................................................................................E-5 4. EFFLUENT MONITORING REQUIREMENTS .........................................................E-5 4.1. Monitoring Location EFF-001 ................................................................................E-5 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS .................................E-9 5.1. Whole Effluent Acute Toxicity Testing ...................................................................E-9 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable .............. E-18 7. RECYCLING MONITORING REQUIREMENTS .................................................... E-18 7.1. Monitoring Location EFF-002 .............................................................................. E-18 8. RECEIVING WATER MONITORING REQUIREMENTS ........................................ E-19 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW- 006, RSW-007, and RSW-008 .............................................................................. E-19 9. OTHER MONITORING REQUIREMENTS ............................................................. E-21 9.1. Biosolids, Monitoring, and Notification – BIO-001 ............................................... E-21 9.2. Pretreatment Monitoring ...................................................................................... E-26 9.3. Salt and Nutrient Management Plan Reporting ................................................... E-29 9.4. Volumetric Monitoring of Wastewater and Recycled Water ................................. E-30 10. REPORTING REQUIREMENTS .......................................................................... E-30 10.1. General Monitoring and Reporting Requirements ............................................. E-30 10.2. Self-Monitoring Reports (SMRs)........................................................................ E-30 10.3. Discharge Monitoring Reports (DMRs) .............................................................. E-34 10.4. Other Reports .................................................................................................... E-34 TABLE OF TABLES Table E-1. Monitoring Station Locations .......................................................................E-3 Table E-2. Influent Monitoring ......................................................................................E-5 Table E-3. Effluent Monitoring at EFF-001 ...................................................................E-6 Table E-4. Approved Test for Acute Toxicity – Fresh Water ...................................... E-10 Table E-5. Approved Tests for Chronic Toxicity – Freshwater ................................... E-14 Table E-6. Recycled Water Monitoring Requirements at EFF-002 ............................. E-18 Table E-7. Receiving Water Monitoring Requirements............................................... E-19 Table E-8. Amount of Biosolids and Frequency of Analysis ....................................... E-21 Table E-9. Biosolids Monitoring Requirements .......................................................... E-22 Table E-10. Monitoring Periods and Reporting Schedule........................................... E-31 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-2 ATTACHMENT E – MONITORING AND REPORTING PROGRAM Section 308 of the federal Clean Water Act (CWA) and sections 122.41(h), (j)-(l), 122.44(i), and 122.48 of title 40 of the Code of Federal Regulations (40 C.F.R.) require that all NPDES permits specify monitoring and reporting requirements. California Water Code sections 13267 and 13383 also authorize the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) to establish monitoring, inspection, entry, reporting, and recordkeeping requirements. This Monitoring and Reporting Program (MRP) establishes monitoring, reporting, and recordkeeping requirements that implement the federal and California laws and/or regulations. 1. GENERAL MONITORING PROVISIONS 1.1. Laboratories analyzing monitoring samples shall be certified by the State Water Resources Control Board (State Water Board), in accordance with the provision of California Water Code section 13176, and must include quality assurance/quality control data with their reports. 1.2. Samples and measurements taken as required herein shall be representative of the volume and nature of the monitored discharge. All samples shall be taken at the monitoring locations specified in this MRP and, unless otherwise specified, before the monitored flow joins or is diluted by any other waste stream, body of water, or substance. Monitoring locations shall not be changed without notification to and approval of the Central Coast Water Board. 1.3. Appropriate flow measurement devices and methods consistent with accepted scientific practices shall be selected and used to ensure the accuracy and reliability of measurements of the volume of monitored discharges. The devices shall be installed, calibrated, and maintained to ensure that the accuracy of the measurements is consistent with the accepted capability of that type of device. Devices selected shall be capable of measuring flows with a maximum deviation of less than ±10 percent from true discharge rates throughout the range of expected discharge volumes. Guidance in selection, installation, calibration, and operation of acceptable flow measurement devices can be obtained from the following references. 1.3.1. A Guide to Methods and Standards for the Measurement of Water Flow, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 421, May 1975, 96 pp. http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication421.pdf 1.3.2. Water Measurement Manual, U.S. Department of Interior, Bureau of Reclamation, Second Edition, Revised Reprint, 1974, 327 pp. https://www.usbr.gov/tsc/techreferences/mands/wmm/index.htm1.3.3. Flow Measurement in Open Channels and Closed Conduits, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 484, October 1977, 982 pp. https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication484v2.pdf CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-3 1.3.3. NPDES Compliance Inspection Manual, Chapter 6 – Flow Measurement, U.S. Environmental Protection Agency (U.S. EPA), Office of Water Enforcement, Publication Number 305-K-17-001, January 2017, 918 pp. https://www.epa.gov/compliance/compliance-inspection-manual-national- pollutant-discharge-elimination-system 1.4. All monitoring instruments and devices used by the Discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. All flow measurement devices shall be calibrated at least once per year to ensure continued accuracy of the devices. 1.5. Monitoring results, including noncompliance, shall be reported at intervals and in a manner specified in this MRP. 1.6. Unless otherwise specified by this MRP, all monitoring shall be conducted according to test procedures established at 40 C.F.R. part 136, Guidelines Establishing Test Procedures for Analysis of Pollutants. All analyses shall be conducted using the lowest practical quantitation limit achievable using the specified methodology. Where effluent limitations are set below the lowest achievable quantitation limits, pollutants not detected at the lowest practical quantitation limits will be considered in compliance with effluent limitations. Analysis for toxic pollutants listed by the California Toxics Rule shall also adhere to guidance and requirements contained in the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (2005) (SIP). 1.7. The Discharger shall ensure that the results of the Discharge Monitoring Report- Quality Assurance (DMR-QA) Study or the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board at the following address: State Water Resources Control Board; Quality Assurance Program Officer; Office of Information Management and Analysis; 1001 I Street, Sacramento, CA 95814 2. MONITORING LOCATIONS The Discharger shall establish the following monitoring locations to demonstrate compliance with the effluent limitations, discharge specifications, and other requirements in this Order: Table E-1. Monitoring Station Locations Discharge Point Name Monitoring Location Name Monitoring Location Description INF-001 Influent wastewater prior to treatment and following all significant inputs to the collection system of untreated wastewater and inflow and infiltration, where representative samples of CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-4 Discharge Point Name Monitoring Location Name Monitoring Location Description wastewater influent can be obtained prior to any plant return flows or treatment processes EFF-001 EFF-001A At a point where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to entering the discharge pipeline to San Luis Obispo Creek: 35.251533°N, 120.676817°W EFF-001B At a point at the end of the discharge pipeline where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to commingling with other waste streams or being discharged into San Luis Obispo Creek: 35.244307°N, 120.680618°W EFF-002 EFF-002 Location where a representative sample of title 22 recycled water can be collected prior to discharge to the recycled water storage tank. Receiving Water RSW-001 At Fox Canyon Road Receiving Water RSW-002 At Mission Receiving Water RSW-003 At Marsh Street Bridge Receiving Water RSW-004 50 feet upstream of effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-005 A location in San Luis Obispo Creek immediately upstream of the confluence with Prefumo Canyon Creek CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-5 Discharge Point Name Monitoring Location Name Monitoring Location Description Receiving Water RSW-006 A location in Prefumo Canyon Creek 50 feet upstream of the confluence with San Luis Obispo Creek Receiving Water RSW-007 Approximately 0.5 miles downstream from effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-008 At Higuera Street Bridge, near US 101 Biosolids BIO-001 Biosolids at the last point in the biosolids handling process where representative samples of residual solids from the treatment process can be obtained 3. INFLUENT MONITORING REQUIREMENTS 3.1. Monitoring Location INF-001 3.1.1. The Discharger shall monitor influent to the facility at INF-001 as below: Table E-2. Influent Monitoring Parameter Units Sample Type Minimum Sampling Frequency Flow Million gallons per day (MGD) Measured 1/Day Biochemical Oxygen Demand 5-day @ 20°C (BOD5)[2] Milligram per liter (mg/L) 24-hour Composite 1/Month[1] Total Suspended Solids (TSS)[2] mg/L 24-hour Composite 1/Month[1] [1] The Discharger shall report the average and maximum daily flows. [2] Collection of BOD5 and TSS samples shall occur on days that effluent samples are collected. BOD shall be monitored in the influent at the same time as it is monitored in the effluent. 4. EFFLUENT MONITORING REQUIREMENTS 4.1. Monitoring Location EFF-001 4.1.1. The Discharger shall monitor effluent discharged at Monitoring Location EFF -001 as specified in Table E-3. Except where specified, all monitoring will be performed at EFF-001A. If more than one analytical test method is listed for a given CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-6 parameter, the Discharger must select from the listed methods and corresponding Minimum Level: Table E-3. Effluent Monitoring at EFF-001 Parameter Units Sample Type Minimum Sampling Frequency Flow MGD Metered 1/Day Instantaneous Maximum Flow MGD Metered 1/Day Maximum Daily Flow Calculated 1/Month Mean Daily Flow MGD Calculated 1/Month Biochemical Oxygen Demand, 5- day (BOD5) mg/L 24-hour Composite 1/Month BOD Mass Emissions Rate pounds per day (lbs/day) Calculated 1/Month BOD5 Percent removal Calculated 1/Month pH[1] standard units Continuous or Grab 1/Day Chlorine, Total Residual[2] mg/L Continuous or Grab Grab samples shall be taken a minimum of twice per day, and within 30 minutes of any excursion above 0.1 mg/L Chlorine Used[2] lbs/day Calculated 1/Day Temperature[1] °C Continuous or Grab 5/Week Total Coliform MPN/100 mL Grab 5/Week Settleable Solids milliliter per liter (ml/L) Grab 1/Week Ammonia (as N) [3] mg/L Grab 1/Week Un-ionized Ammonia (as N) [1] mg/L Calculated 1/Week Total Suspended Solids (TSS) mg/L 24-hr. composite 1/Week TSS Percent removal Calculated 1/Week Turbidity Nephelo- metric Turbidity 24-hr. composite 1/10 days CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-7 Parameter Units Sample Type Minimum Sampling Frequency Units (NTU) Dissolved Oxygen mg/L Grab 1/Month Color Color units Grab 1/Month Oil and Grease mg/L Grab 1/Month Total Kjeldahl Nitrogen (TKN) (as N) mg/L Grab 1/Month Chlorodibromomethane (aka Dibromochloromethane) μg/L 24-hr. composite 1/Month[4] Chloroform μg/L 24-hr. composite 1/Month[4] Dichlorobromomethane μg/L 24-hr. composite 1/Month[4] Methylene Chloride μg/L 24-hr. composite 1/Month[4] Pentachlorophenol μg/L 24-hr. composite 1/Month[4] Nitrate (as N) mg/L Grab 1/Month Nitrite (as N) mg/L Grab 1/Month Methylene Blue Active Substances (MBAS) mg/L 24-hr. composite 1/Month[4] Molybdenum mg/L Grab 1/Month Dissolved Orthophosphate (as P) mg/L Grab 1/Month Total Phosphate (as P) mg/L Grab 1/Month Total Dissolved Solids (TDS) mg/L Grab 1/Month Sodium mg/L Grab 1/Month Chloride mg/L Grab 1/Month Sulfate mg/L Grab 1/Month Hardness (CaCO3)[5] mg/L 24-hr. composite 1/Quarter Boron mg/L Grab 1/Year (in October) Cobalt mg/L Grab 1/Year (in October) Iron mg/L Grab 1/Year (in October) Lithium mg/L Grab 1/Year (in October) Manganese mg/L Grab 1/Year (in October) Vanadium mg/L Grab 1/Year (in October) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-8 Parameter Units Sample Type Minimum Sampling Frequency Acute Toxicity[6] ”Pass/Fail” and % Effect Grab 1/Year Chronic Toxicity[6] “Pass/Fail and % Effect” Grab 1/Month[7] California Toxics Rule (CTR) Pollutants[8], [9] μg/L 24-Hour composite 1/Year (in October) Title 22 Pollutants[10], [11] μg/L 24-Hour composite 1/Year (in October) [1] Temperature and pH are to be measured at the same time the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] Sampling shall be concurrent with sampling of receiving water for ammonia. [4] If no exceedances of the effluent limitation occur for a minimum of 12 consecutive months of monitoring then the frequency of monitoring shall be reduced to quarterly. Subsequently, if an exceedance of the effluent limitation occurs during quarterly monitoring, the monitoring frequency shall return to monthly. The Discharger must notify the Central Coast Water Board of the change in monitoring frequency . [5] Hardness monitoring will occur on the same day and time as the California Toxics Rule (CTR) pollutants to allow for conversion from total recoverable to dissolved for hardness dependent metals. [6] Whole effluent acute and chronic toxicity monitoring shall be conducted according to the requirements established in sections 5.1 and 5.2, respectively, of this MRP. [7] Once per year, in October, chronic toxicity monitoring must be performed at EFF- 001B instead of at EFF-001A. [8] The California Toxics Rule (CTR) pollutants are those listed by the CTR at 40 C.F.R. 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). The Discharger shall instruct its analytical laboratory to establish calibration standards so that the Minimum Levels (MLs) presented in Appendix 4 of the SIP are the lowest calibration standards. The Discharger and its analytical laboratory shall select MLs which are below applicable water quality criteria of the CTR; and when applicable water quality criteria are below all MLs, the Discharger and its analytical laboratory shall select the lowest ML. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-9 [9] Monitoring for the CTR pollutants in effluent shall occur simultaneously with monitoring required for the CTR pollutants in receiving water. [10] The title 22 pollutants are those pollutants for which Maximum Contaminant Levels (MCLs) have been established at title 22, division 4, chapter 15, sections 64431 (inorganic chemicals) and 64444 (organic chemicals) of the California Code of Regulations. Where these pollutants are included in other groups of pollutants (CTR Priority Pollutants), monitoring does not need to be duplicated. Analytical methods shall adhere to the Detection Limits for Purposes of Reporting (DLRs) established by title 22 of the California Code of Regulations, division 4, chapter 15, sections 64432 and 64445.1. [11] Monitoring for the title 22 pollutants in effluent shall occur simultaneously with monitoring required for the title 22 pollutants in receiving water. 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS 5.1. Whole Effluent Acute Toxicity Testing 5.1.1. Routine Acute Toxicity Monitoring Frequency. The Discharger shall conduct at least one acute aquatic toxicity test using the most sensitive species every calendar year during which there is expected to be at least 15 days of discharge in at least one calendar quarter. For the purposes of acute toxicity, the calendar year starts from the initiation of routine monitoring. If the Discharger is unable to sample within the calendar year due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar year was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. 5.1.2. Discharge In-stream Waste Concentration (IWC) for Acute Toxicity. The IWC for this discharge is 100 percent effluent. 5.1.3. Most Sensitive Species. The test species used for acute toxicity testing shall be the most sensitive species. To be consistent with previous Order R3-2014-0033, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct acute toxicity testing from the effective date of this permit until the completion of the required acute species sensitivity screening detailed in section 5.1.6 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation, and the Central Coast Water Board determines that the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-10 Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.1.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.1.5. Acute Freshwater Species and Test Methods. The Discharger shall conduct acute toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136). Approved tests methods for acute toxicity are listed in Table E-4 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-4. Approved Test for Acute Toxicity – Fresh Water Species Effect Test Duration (hours) Test Method Fathead Minnow (Pimephales promelas) Survival 96 Survival Test Method 2000.0 Water Flea (Ceriodaphnia dubia) Survival 48 Survival Test Method 2002.0 5.1.6. Acute Species Sensitivity Screening. The Discharger shall conduct one species sensitivity screening test during the Order’s first required sample collection for acute toxicity. The Discharger shall collect a single effluent sample to initiate and concurrently conduct two toxicity tests using the fish and invertebrate species referenced in Table E-4 above. This sample shall also be analyzed for the parameter(s) required on a mon thly and quarterly frequency in Table E-3, during that given month. Samples for the species sensitivity screening shall be analyzed using the TST approach. The species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-11 than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. 5.1.7. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.1.7.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent Effect” for acute toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.80 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.1.7.2. If the effluent toxicity test does not meet all test acceptability criteria (TAC) specified in the referenced test method, Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136) then the Discharger must resample and re-test within 7 days. 5.1.7.3. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.1.7.4. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.1.8. Notification. The Discharger shall notify the Central Coast Water Board of an exceedance of the acute toxicity trigger of 90 percent survival as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-12 Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.1.9. Accelerated Monitoring Requirements. If the result of any acute toxicity test fails to meet the single test minimum trigger (70 percent survival), and the testing meets all TAC, the Discharger shall take two more samples, one within 14 days and one within 21 days following receipt of the initial sample result. If any one of the additional samples do not comply with the three -sample median minimum limitation (90 percent survival), the Discharger shall initiate a Toxicity Reduction Evaluation (TRE) in accordance with section 5.4 of the MRP. If the two additional samples are in compliance with the acute toxicity requirement and testing meets all TAC, then a TRE will not be required. 5.1.10. Reporting. The Self-Monitoring Report (SMR) shall include a full laboratory report for each toxicity test (WET report). The WET report shall be prepared using the format and content of section 12 (Report Preparation) of Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 5th edition or subsequent editions), including: 5.1.10.1. The toxicity test results in percent (%) survival for the 100 percent effluent sample. 5.1.10.2. The toxicity test results for the TST approach, reported as “Pass” or “Fail” and “Percent Effect” at the acute toxicity IWC for the discharge. 5.1.10.3. Water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.1.10.4. TRE/Toxicity Identification Evaluation (TIE) results. The Executive Officer shall be notified no later than 30 days from completion of each aspect of TRE/TIE analyses. 5.1.10.5. Statistical program (e.g., TST calculator, CETIS, etc.) output results for each toxicity test. 5.2. Chronic Toxicity Monitoring Requirements – Monitoring Location EFF-001 5.2.1. Routine Chronic Toxicity Monitoring Frequency. The Discharger shall conduct at least one chronic aquatic toxicity test every calendar month during which there is expected to be at least 15 days of discharge. Initiation of the routine monitoring test shall be at a time that would allow any required Med ian Monthly Effluent Limitation (MMEL) compliance tests to be initiated within the same calendar month as the routine monitoring test. For routine chronic toxicity monitoring, the Discharger shall conduct at least one chronic toxicity test using the most sensitive species each calendar month during which there is expected to be at least 15 days of discharge. For the purposes of chronic toxicity, the calendar month starts from the initiation of routine monitoring. The Discharger shall ensure there is sufficient time to perform the MMEL compliance testing within the defined calendar month, should the initial toxicity test result in a “Fail”. If the Discharger is unable to sample within the calendar CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-13 month due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar month was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. The Discharger may request to reduce the monitoring frequency from once per calendar month to once per calendar quarter if all of the following conditions are met: 1) the toxicity requirements in this permit have been followed; and 2) there were no violations of the MMEL or Maximum Daily Effluent Limitation (MDEL) for chronic toxicity within the last five years. If a chronic toxicity test results in a “Fail” at the IWC during reduced monitoring, the frequency is automatically increased back to once per month for a period of five years. 5.2.2. Discharge In-stream Waste Concentration (IWC). The IWC for this discharge is 100 percent effluent. 5.2.3. Most Sensitive Species. The test species used for chronic toxicity testing shall be the most sensitive species. To be consistent with Order No. R3 -2014-003, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct chronic toxicity testing from the effective date of this permit until the completion of the required chronic species sensitivity screening described in section 5.2.7 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation and the Central Coast Water Board determines that the Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.2.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.2.5. Chronic Freshwater Species and Test Methods. The Discharger shall conduct chronic toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002; Table IA, 40 C.F.R. part 136). Approved CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-14 tests methods for chronic toxicity are listed in Table E-5 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-5. Approved Tests for Chronic Toxicity – Freshwater Species Effect Test Duration (days) Test Method Fathead Minnow (Pimephales promelas) Larval Survival and Growth 7 Larval Survival and Growth Test Method 1000.0 Water Flea (Ceriodaphnia dubia) Survival and Reproduction 6 to 8 days Survival and Reproduction Test Method 1002.0 Green Alga (Selenastrum capricornutum) Growth 4 days Growth Test Method 1003.0 5.2.6. Median Monthly Effluent Limitation (MMEL) Compliance Monitoring. If a chronic toxicity test conducted during routine monitoring results in a “Fail” at the IWC, the Discharger shall conduct a maximum of two chronic toxicity MMEL compliance tests. The MMEL compliance tests shall be initiated within the same calendar month that the first routine chronic toxicity test was initiated that resulted in a “Fail” at the IWC. If the first chronic toxicity MMEL compliance test results in a “Fail” at the IWC, then the second chronic toxicity MMEL compliance test is not required. 5.2.7. Chronic Species Sensitivity Screening. The Discharger shall conduct four species sensitivity screening tests within 18 months of the effective date of this permit and four species sensitivity screening tests within one year of submitting the ROWD for the Facility, with one set of screenings conducted in each quarter for four consecutive quarters. For each set of species sensitivity screenings, the Discharger shall collect a single effluent sample to initiate and concurrently conduct three toxicity tests using the fish, invertebrate, and alga species referenced in Table E-5 above. This sample shall also be analyzed for the parameter(s) required on a monthly and quarterly frequency in Table E -3, during that given month. As allowed under the test method for the Ceriodaphnia dubia and the Pimephales promelas, a second and third sample shall be collected for use as test solution renewal water as the seven-day toxicity test progresses. Samples for the species sensitivity screening shall be analyzed using the TST approach. After the fourth set of species sensitivity screening, the species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-15 repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. During the calendar month, toxicity tests used to determine the most sensitive test species shall be reported as effluent compliance monitoring results for the MDEL and MMEL for chronic toxicity. 5.2.8. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.2.8.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent (%) Effect” for chronic toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.2.8.2. The MDEL for chronic toxicity is exceeded and a violation will be flagged when a toxicity test during routine monitoring results in “Fail” for the sub -lethal endpoint in accordance with the TST approach and the “Percent Effect” is greater than or equal to 50 percent for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. 5.2.8.3. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. 5.2.8.4. If the effluent toxicity test does not meet all TAC specified in the referenced test method, Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002) then the Discharger must resample and re-test within 14 days. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-16 5.2.8.5. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.2.8.6. Monthly reference toxicant testing is sufficient if in accordance with Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). All reference toxicant test results should be reviewed and reported using the effects concentration at 25 percent (EC25). 5.2.8.7. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.2.9. Notification. The Discharger shall notify the Central Coast Water Board of a violation of a toxicity MDEL or MMEL as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.2.10. Routine Reporting. The SMR shall include a full laboratory report for each chronic toxicity test. This report shall be prepared using the format and content of the test methods manual in section 10 of Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002), Report Preparation, and shall include: 5.2.10.1. The valid toxicity test results for the TST statistical approach, reported as “Pass” or “Fail” and “Percent Effect” at the chronic toxicity IWC for the discharge. All toxicity test results (whether identified as valid or otherwise) conducted during the calendar month shall be reported on the SMR due date specified in Table E-10. 5.2.10.2. Summary water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.2.10.3. The statistical analysis used in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10- 003, 2010) Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. 5.2.10.4. Statistical program (e.g., TST calculator, CETIS, etc.) output results, including graphical plots, for each toxicity test. 5.2.10.5. Tabular data and graphical plots clearly showing the laboratory’s performance for the reference toxicant for the previous 20 tests and the laboratory’s performance for the control mean, control standard deviation, and control coefficient of variation for the previous 12-month period. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-17 5.2.10.6. Any additional quality assurance/quality control (QA/QC) documentation or any additional chronic toxicity-related information, upon written request from the Central Coast Water Board. 5.3. Accelerated Monitoring Requirements 5.3.1. When acute toxicity is detected in the effluent, or when the chronic toxicity effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all TAC, the Discharger shall initiate accelerated monitoring to confirm the effluent toxicity. 5.3.2. The Discharger shall implement an accelerated monitoring frequency consisting of performing three toxicity tests in a six-week period following the first failed test results. 5.3.3. If implementation of the generic Toxicity Reduction Evaluation (TRE) Work Plan indicates the source of the exceedance of the effluent limitation or toxicity trigger (for instance, a temporary plant upset), then only one additional test is necessary. If exceedance of the effluent limitation or toxicity trigger is detected in this test, the Discharger will continue with accelerated monitoring requirements or implement the Toxicity Identification and Toxicity Reduction Evaluations. 5.3.4. If none of the three tests indicated exceedance of the effluent limitation or toxicity trigger, then the Discharger may return to the normal testing frequency. 5.4. Toxicity Identification Evaluations (TIE) and Toxicity Reduction Evaluation (TRE) Process 5.4.1. A TIE shall be triggered if testing from the accelerated monitoring frequency indicates any of the following: 5.4.1.1. Two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. 5.4.1.2. The TIE shall be initiated within 15 days following failure of the second accelerated monitoring test. 5.4.1.3. If a TIE is triggered prior to the completion of the accelerated testing, the accelerated testing schedule may be terminated, or used as necessary in performing the TIE. 5.4.2. The TIE shall be conducted to identify and evaluate toxicity in accordance with procedures recommended by the U.S. EPA, which include the following: 5.4.2.1. Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents, Phase I, (U.S. EPA, 1992a); 5.4.2.2. Methods for Aquatic Toxicity Identification Evaluations: Phase I Toxicity Characterization Procedures, Second Edition (U.S. EPA, 1991a); 5.4.2.3. Methods for Aquatic Toxicity Identification Evaluations: Phase II Toxicity Identification Procedures for Sampling Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993a); and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-18 5.4.2.4. Methods for Aquatic Toxicity Identification Evaluations: Phase III Toxicity Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993b). 5.4.3. As part of the TIE investigation, the Discharger shall be required to implement its TRE Work Plan. The Discharger shall take all reasonable steps to control toxicity once the source of the toxicity is identified. A failure to conduct required toxici ty tests or a TRE within a designated period shall result appropriate enforcement action. Recommended guidance in conducting a TRE includes the following: 5.4.3.1. Toxicity Reduction Evaluation Guidance for Municipal Wastewater Treatment Plants, August 1999, EPA/833B-99/002; and 5.4.3.2. Clarifications Regarding Toxicity Reduction and Identification Evaluations in the National Pollutant Discharge Elimination System Program dated March 27, 2001, U.S. EPA Office of Wastewater Management, Office of Regulatory Enforcement. 5.4.4. The Central Coast Water Board may also require the Discharger conduct a TRE if other information indicates toxicity (e.g., results of additional monitoring, results of monitoring at a higher concentration than the IWC, fish kills, intermittent recurring toxicity), or if there is no effluent available to complete routine monitoring, a MMET test or a MMEL Compliance Test. 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable 7. RECYCLING MONITORING REQUIREMENTS 7.1. Monitoring Location EFF-002 7.1.1. The Discharger shall monitor recycled water at Monitoring Location EFF-002 as described below: Table E-6. Recycled Water Monitoring Requirements at EFF-002 Parameter Units Sample Type Minimum Sampling Frequency[3] Daily Flow MGD Metered Continuous Total Coliform MPN/100 mL Grab 1/Day Turbidity[1] NTU Metered Continuous pH standard units Grab 1/Day Total Chlorine Residual[2] mg/L Metered Continuous [1] Turbidity to be sampled immediately downstream of the membrane bioreactors. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-19 the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] Monitoring is not required during periods recycled water is not being produced for use outside of the Facility. The Discharger shall specify within the SMR if production of recycled water took place during the monitoring period. 7.1.2. In the event the Producer is unable to comply with the conditions of the water recycling requirements and prohibitions, the Producer shall immediately notify the Central Coast Water Board by telephone and submit a written follow-up report with two weeks of the noncompliance. The written report shall include pertinent information explaining reasons for the noncompliance and shall indicate what steps are being taken to prevent the problems from recurring. 7.1.3. An annual self-monitoring report shall be submitted to the Central Coast Water Board by April 1 of the following year. The report shall include the following: 7.1.3.1. A letter transmitting self-monitoring reports shall accompany each report. The letter shall include a discussion of violations found during the reporting period and actions taken or planned for correcting noted violations, such as operation or facility modifications. If the Producer has previously submitted a report describing corrective actions or a time schedule for implementing corrective actions, reference to the previous correspondence will be satisfactory. The transmittal letter shall contain a statement by the Producer or the Producer’s authorized agent, under penalty of perjury, that to the best of the signer’s knowledge the report is true, accurate, and complete. 7.1.3.2. Tabulations of the results of each required analysis by the Producer specified in Table E-6 by date, time, type of sample, and station. 8. RECEIVING WATER MONITORING REQUIREMENTS 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW-008 8.1.1. The Discharger shall monitor the receiving water at Monitoring Locations RSW - 001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW- 008 as follows: Table E-7. Receiving Water Monitoring Requirements Parameter Units Sample Type Sampling Station [1] Minimum Sampling Frequency Flow[2] CFS Instantaneous 4, 5, 7, 8 1/Month Flow MGD Estimated 4, 5, 7, 8 1/Month Turbidity[2] NTU Grab 4, 5, 1/Month Color[2] Color units Grab 4, 5 1/Month CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-20 Parameter Units Sample Type Sampling Station [1] Minimum Sampling Frequency pH[2][4] standard units (s.u.) Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Temperature[4] °C Grab 4, 5 1/Month Un-ionized Ammonia (as N) [4] mg/L Calculated 4, 5 1/Month Nitrate (as N) mg/L Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Total Phosphate (as P) mg/L Grab 5, 7, 8 1/Month Ammonia, Total (as N) [3] mg/L Grab 5, 7, 8 1/Month Total Kjeldahl Nitrogen (as N) mg/L Grab 5, 7, 8 1/Month Total Dissolved Solids (TDS) mg/L Grab 4, 5, 7, 8 1/Month Chloride mg/L Grab 4, 5, 7, 8 1/Month Sulfate mg/L Grab 4, 5, 7, 8 1/Month Sodium mg/L Grab 4, 5, 7, 8 1/Quarter Boron mg/L Grab 4, 5, 7, 8 1/Quarter Hardness, as CaCO3 mg/L Grab 4, 5, 7, 8 1/Quarter Molybdenum mg/L Grab 4, 5, 7, 8 1/Year Methylene Blue Activated Substances mg/L Grab 4, 5, 7, 8 1/Year E. coli MPN/100 mL Grab 4, 5, 7, 8 1/Quarter CTR Pollutants[5], [6] µg/L Grab 4, 5 1/Year Title 22 Pollutants[7], [8] µg/L Grab 4, 5 1/Year [1] Samples shall be obtained only when safe to do so. [2] The San Luis Obispo Creek flow rate shall be used to determine the upstream and downstream stations where these constituents shall be monitored as follows: If the creek flows underground between Monitoring Location RSW-002 and the discharge point, samples shall be obtained from Monitoring Locations RSW-002. If the creek flows aboveground from Monitoring Location RSW-002 to the discharge point, samples shall be obtained from Monitoring Location RSW-004. In either case, Monitoring Location RSW-005 shall be the downstream location. [3] Sampling shall be concurrent with sampling of effluent for ammonia. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-21 [4] Temperature and pH are to be measured at the same time that the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [5] The CTR pollutants are those listed by the CTR at 40 CFR 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). [6] Monitoring of receiving water for the CTR pollutants shall occur simultaneously with effluent monitoring for the CTR pollutants. [7] The title 22 pollutants are those for which primary MCLs have been established and which are listed in sections 64431-A and 64444-A of the California Code of Regulations, title 22, division 4, chapter 15. Where these pollutants are also identified as CTR Priority Pollutants, monitoring does not need to be duplicated. [8] Monitoring of receiving water for the title 22 Pollutants shall occur simultaneously with effluent monitoring for title 22 pollutants. 9. OTHER MONITORING REQUIREMENTS 9.1. Biosolids, Monitoring, and Notification – BIO-001 9.1.1. A representative sample of biosolids shall be obtained from the last point in the handling process (i.e., in the drying beds just prior to removal or from a pond bottom). All constituents shall be analyzed annually for total concentrations for comparison with Total Threshold Limit Concentration (TTLC) criteria. The Waste Extraction Test shall be performed on any constituent when the total concentration of the waste exceeds ten times the Soluble Threshold Limit Concentration (STLC) for that substance. Twelve (12) discrete representative samples shall be collected at separate locations in the biosolids ready for disposal. These 12 samples shall be composited to form one (1) sample for constituent analysis. For accumulated, previously untested biosolids, the Discharger shall develop a representative sampling plan including number and location of sampling points and collect representative samples. The analysis shall test for the metals required in 40 C.F.R. 503.16 (for land application) or 503.26 (for surface disposal), using the methods in Test Methods for Evaluating Solid Waste, Physical/Chemical Methods (U.S. EPA Publication SW-846, all applicable editions and updates), as required in 503.8(b)(4), at the minimum frequencies established therein, provided in the table below. Table E-8. Amount of Biosolids and Frequency of Analysis Amount[1] (dry metric tons/365-day period) Minimum Sampling Frequency[2] Greater than zero, but less than 290 Once per year Equal to or greater than 290 but less than 1,500 Once per quarter (four times per year) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-22 Amount[1] (dry metric tons/365-day period) Minimum Sampling Frequency[2] Equal to or greater than 1,500 but less than 15,000 Once per sixty days (six times per year) Greater than 15,000 Once per month (twelve times per year) [1] For land application, either the amount of bulk biosolids applied to the land or the amount prepared for sale or give-away in a bag or other container for application to the land (dry weight basis). If the Discharger’s biosolids are directly land applied without further treatment by another preparer, biosolids shall also be tested for organic-N, ammonium-N, and nitrate-N at the frequencies required. For surface disposal, the amount of biosolids placed on an active sludge unit (dry weight basis). [2] Test results shall be expressed in mg pollutant per kg biosolids on a 100% dry weight basis. With U.S. EPA approval the amount of biosolids and minimum sampling frequency can coincide with the testing regiment implemented for Cal recycle. Biosolids shall be analyzed for the constituents in the table below. Table E-9. Biosolids Monitoring Requirements Parameter Units Sample Type Minimum Sampling Frequency Quantity Removed Tons or yd3 Measured During Removal Location of Reuse/Disposal General Public or Specific Site -- -- Moisture Content Percent Grab Per Table E-8 (above) pH standard units Grab Per Table E-8 (above) Total Kjeldahl Nitrogen mg/kg[1] Grab Per Table E-8 (above) Ammonia (as N) mg/kg[1] Grab Per Table E-8 (above) Nitrite (as N) mg/kg[1] Grab Per Table E-8 (above) Total Phosphorus mg/kg[1] Grab Per Table E-8 (above) Oil and Grease mg/kg[1] Grab Per Table E-8 (above) Arsenic mg/kg[1] Grab Per Table E-8 (above) Boron mg/kg[1] Grab Per Table E-8 (above) Cadmium mg/kg[1] Grab Per Table E-8 (above) Copper mg/kg[1] Grab Per Table E-8 (above) Chromium (Total) mg/kg[1] Grab Per Table E-8 (above) Lead mg/kg[1] Grab Per Table E-8 (above) Mercury mg/kg[1] Grab Per Table E-8 (above) Molybdenum mg/kg[1] Grab Per Table E-8 (above) Nickel mg/kg[1] Grab Per Table E-8 (above) Selenium mg/kg[1] Grab Per Table E-8 (above) CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-23 Parameter Units Sample Type Minimum Sampling Frequency Zinc mg/kg[1] Grab Per Table E-8 (above) [1] Total sample (including solids and any liquid portion) to be analyzed and results reported as mg/kg based on the dry weight of the sample. 9.1.2. Prior to land application, the Discharger shall demonstrate that the biosolids meet Class A or Class B pathogen reduction levels by one of the methods listed in 40 C.F.R. 503.32 (unless transferred to another preparer who demonstrates pathogen reduction). Prior to disposal in a surface disposal site, the Discharger shall demonstrate that the biosolids meet Class B levels or shall ensure that the site is covered at the end of each operating day. If pathogen reduction is demonstrated using a “Process to Significantly/Further Reduce Pathogens “(PFRP), the Discharger shall maintain daily records of the operating parameters to achieve this reduction. The following applies when biosolids from the Discharger are directly land applied as Class B, without further treatment by a second preparer. If the Discharger demonstrates pathogen reduction by direct testing for fecal coliforms and/or pathogens, samples must be drawn at the frequency in the Amount/Frequency table above. If the Discharger demonstrates Class B pathogen reduction by testing for fecal coliform, at least seven grab samples must be drawn and analyzed during each monitoring event, and a geometr ic mean calculated from these seven samples. If the Discharger demonstrates Class A pathogen reduction by testing for fecal coliform and/or salmonella, plus one of the PFRP processes or testing for enteric viruses and helminth ova at least four samples of fecal coliform or salmonella must be drawn during each monitoring event. All four samples must meet the limits specified in 503.32(a). 9.1.3. For biosolids that are land applied or placed in a surface disposal site, the Discharger shall track and keep records of the operational parameters used to achieve Vector Attraction Reduction requirements in 40 C.F.R. 503.33(b). 9.1.4. Class 1 facilities (facilities with pretreatment programs or others designated as Class 1 by the Regional Administrator) and federal facilities with greater than five million gallons per day (MGD) influent flow shall sample biosolids for pollutants listed under CWA section 307(a), as required in the pretreatment section of the permit for Publicly Owned Treatment Works (POTWs) with pretreatment programs. Class 1 facilities and federal facilities greater than 5 MGD shall test dioxins/dibenzofurans using a detection limit of less than one pg/g at the time of their next priority pollutant scan if they have not done so within the past five years, and once per five years thereafter. 9.1.5. The biosolids shall be tested annually, or more frequently if necessary, to determine hazardousness. All constituents regulated under title 22 California Code or Regulations, division 5, chapter 11, article 3 shall be analyzed for comparison with TTLC criteria. The waste extraction test shall be performed on CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-24 any constituent when the total concentration of the waste exceeds ten times the STLC limit for that substance. 9.1.6. If biosolids are placed in a surface disposal site (dedicated land disposal site or monofill), a qualified groundwater scientist shall develop a groundwater monitoring program for the site, or shall certify that the placement of biosolids on the site will not contaminate an aquifer. 9.1.7. Biosolids placed in a municipal landfill shall be tested by the Paint Filter Liquids Test (U.S. EPA Method 9095) at the frequency determined by Table E-9, or more often if necessary, to demonstrate that there are no free liquids. 9.1.8. The Discharger, either directly or through contractual agreements with their biosolids management contractors, shall comply with the following notification requirements: 9.1.8.1. Notification of non-compliance. The Discharger shall notify U.S. EPA Region 9, the State Water Board, and the Regional Water Board located in the region where the biosolids are used or disposed, of any non-compliance within 24 hours if the noncompliance may seriously endanger health or the environment. For other instances of non-compliance, the Discharger shall notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance in writing within five working days of becoming aware of the non -compliance. The Discharger shall require their biosolids management contractors to notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance within the same time frames. 9.1.8.2. If biosolids are shipped to another state or Native American lands, the Discharger must send notice at least 60 days prior to the shipment to the permitting authorities in the receiving state or Native American land (the U.S. EPA Regional Office for that area and the State/Native American authorities). 9.1.8.3. For land application (in cases where Class B biosolids are directly applied without further treatment): Prior to reuse of any biosolids from the Discharger’s facility to a new or previously unreported site, the Discharger shall notify U.S. EPA, the Central Coast Water Board, and any other affected Regional Water Board. The notification shall include description of the crops or vegetation to be grown, proposed loading rates and determination of agronomic rates. If any biosolids within a given monitoring period do not meet 40 C.F.R. 503.13 metals concentrations limits, the Discharger (or its contractor) must pre-notify U.S. EPA, and determine the cumulative metals loading to that site to date, as required in 40 C.F.R. 503.12. The Discharger shall notify the applier of all the applier’s requirements under 40 C.F.R. part 503, including the requirement that the applier certify that the management practices, site restrictions, and any applicable vector attraction reduction requirements have been met. The Discharger shall require the applier to certify at the end of 38 months following application of Class B biosolids that the harvesting restrictions in effect for up to 38 months have been met. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-25 9.1.8.4. For surface disposal: Prior to disposal to a new or previously unreported site, the Discharger shall notify U.S. EPA and the Central Coast Water Board. The notice shall include a description and a topographic map of the proposed site, depth to ground water, whether the site is lined or unlined, site operator, site owner, and any State or local permits. The notice shall describe procedures for ensuring public access and grazing restrictions for three years following site closure. The notice shall include a ground water monitoring plan or description of why ground water monitoring is not required. 9.1.9. The Discharger shall submit an annual biosolids report to the U.S. EPA Region 9 Biosolids Coordinator and Central Coast Water Board by February 19th of each year (per U.S. EPA guidance and 40 C.F.R. part 503) for the period covering the previous calendar year. This report shall include: 9.1.9.1. Annual biosolids removed in dry tons and percent solids. 9.1.9.2. If appropriate, a narrative description of biosolids dewatering and other treatment processes, including process parameters, including a schematic diagram showing biosolids handling facilities. For example, if drying beds are used, report depth of application and drying time. If composting is used, report the temperature achieved and duration. 9.1.9.3. A description of disposal methods, including the following information as applicable related to the disposal methods used at the facility. If more than one method is used, include the percentage and tonnage of annual biosolids production disposed by each method. 9.1.9.3.1. For landfill disposal include: 1) the Regional Water Board waste discharge requirement (WDR) numbers that regulate the landfills used, 2) the present classifications of the landfills used, 3) the results of any ground water monitoring, 4) certifications of management practices, and 5) the names and locations of the facilities receiving biosolids. 9.1.9.3.2. For land application include: 1) the location of the site(s), 2) the Regional Water Board's WDR numbers that regulate the site(s), 3) the application rate in lbs/acre/year (specify wet or dry), 4) certifications of management practices and site restrictions, and 5) subsequent uses of the land. 9.1.9.3.3. For offsite application by a licensed hauler and composter include: 1) the name, address and U.S. EPA license number of the hauler and composter. 9.1.9.4. Copies of analytical data required by other agencies (i.e. U.S. EPA or County Health Department) and licensed disposal facilities (i.e. landfill, land application, or composting facility) for the previous year. 9.1.9.5. Descriptions of pathogen reduction methods and vector attraction reduction methods. Including supporting time and temperature data, and certifications, as required in 40 C.F.R. 503.17 and 503.27. 9.1.9.6. Names mailing address, and street addresses of persons who received biosolids for storage, further treatment, disposal in a municipal waste landfill, or CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-26 for other use or disposal methods not covered above, and amounts delivered to each. 9.1.9.7. For all biosolids used or disposed at the Discharger’s facility, the site and management practice information and certification required in 40 C.F.R. 503.17 and 503.27. 9.1.9.8. For all biosolids temporarily stored, the information required in 40 C.F.R. 503.20 is required to demonstrate temporary storage. 9.1.9.9. Reports shall be submitted in electronically using EPA’s Central Data Exchange website at CDX Home | Central Data Exchange | US EPA (cdx.epa.gov). A PDF copy can be printed and sent to: Executive Officer Central Coast Water Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 9.2. Pretreatment Monitoring By February 1 of each year, the Discharger shall submit an Annual Report to the State Water Board, Central Coast Water Board, and U.S. EPA describing the Discharger’s pretreatment activities over the previous 12 months. In the event that the Discharger is not in compliance with any pretreatment condition of this Order or resulting from pretreatment audits or compliance inspections, then the Discharger shall also include the reasons for noncompliance and state how and when the Discharger will comply with such conditions and requirements. This report shall contain, but not be limited to, the following information: 9.2.1. A summary of analytical results from representative, flow-proportioned, 24-hour composite sampling of the plant's effluent and sludge as provided in the relevant sections of this MRP. The Discharger shall also provide any influent, effluent, or sludge monitoring data for nonpriority pollutants which the Discharger believes may be causing or contributing to interference, pass-through, or adversely impacting sludge quality. Sampling and analysis shall be performed in accordance with the techniques prescribed in 40 C.F.R. part 136 and amendments thereto. 9.2.2. A discussion of upset, interference, or pass-through incidents, if any, at the POTW, which the Discharger knows or suspects were caused by industrial users of the POTW system. The discussion shall include the reasons why incidents occurred, corrective actions taken and, if known, the name and address of the industrial user(s), responsible. Discussions shall also include a review of applicable pollutant limitations to determine whether any additional limitations or changes to existing requirements may be necessary to prevent pass-through, interference, or noncompliance with sludge disposal requirements. 9.2.3. The cumulative number of industrial users that the Discharger has notified regarding Baseline Monitoring Reports and the cumulative number of industrial user responses. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-27 9.2.4. An updated list of the Discharger's industrial users, including their names and addresses, or a list of deletions and additions keyed to a previously submitted list. The Discharger shall provide a brief explanation for each deletion. The list shall identify the industrial users subject to Federal Categorical Standards by specifying which set(s) of standards are applicable. The list shall indicate which categorical industries, or specific pollutants from each industry, are subject to local limitations that are more stringent than the Federal Categorical Standards. The Discharger shall also list the non-categorical industrial users that are subject only to local discharge limitations. The Discharger shall characterize the compliance status of each industrial user by employing the following descriptions. 9.2.4.1. In compliance with Baseline Monitoring Report requirements (where applicable); 9.2.4.2. Consistently achieving compliance; 9.2.4.3. Inconsistently achieving compliance; 9.2.4.4. Significantly violated applicable pretreatment requirements defined by 40 C.F.R. 403.8 (f)(2)(vii); 9.2.4.5. On a schedule to achieve compliance (include the date final compliance is required); 9.2.4.6. Not achieving compliance and not on a compliance schedule; or 9.2.4.7. The Discharger does not know the industrial user's compliance status. A report describing the compliance status of any industrial user characterized by descriptions in Items 9.2.4.4.3. through 9.2.4.4.7., above, shall be submitted quarterly from the annual report date to the State Water Board, Central Coast Water Board, and U.S. EPA. The report shall identify the specific compliance status of each such industrial user. This quarterly reporting requirement shall commence upon issuance of this Order. Quarterly reports shall be submitted May 1, August 1, and November 1. The fourth quarter report shall be incorporated in the Annual Report (February 1). Quarterly reports shall briefly describe POTW compliance with audit/pretreatment compliance inspection requirements. If none of the aforementioned conditions exist, at a minimum, a letter indicating that all industries are in compliance and no violations or changes to the pretreatment program have occurred during the quarter must be submitted. 9.2.4.8. A summary of inspection and sampling activities conducted by the Discharger during the past year to gather information and data regarding industrial users. The summary shall include the following: 9.2.4.8.1. Names and addresses of the industrial users subject to surveillance by the Discharger and an explanation of whether they were inspected, sampled, or both and the frequency of these activities at each user; and 9.2.4.8.2. Conclusions or results from the inspection or sampling of each industrial user. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-28 9.2.4.9. A summary of compliance and enforcement activities during the past year. The summary shall include names and addresses of the industrial users affected by the following actions. 9.2.4.9.1. Warning letters or notices of violation regarding the industrial users' apparent noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the apparent violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.2. Administrative Orders regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.3. Civil actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.4. Criminal actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned Federal Categorical Standards or local discharge limitations; 9.2.4.9.5. Assessment of monetary penalties. For each industrial user, identify the amount of the penalties; 9.2.4.9.6. Restriction of flow to the POTW; and 9.2.4.9.7. Disconnection from discharge to the POTW. 9.2.4.10. Description of any significant changes in operating the pretreatment program, which differ from the information in the Discharger's approved POTW Pretreatment Program including, but not limited to, changes concerning: 9.2.4.10.1. The program's administrative structure; 9.2.4.10.2. Local industrial discharge limitations; 9.2.4.10.3. Monitoring program and monitoring frequencies; 9.2.4.10.4. Legal authority or enforcement policy; 9.2.4.10.5. Funding mechanisms; 9.2.4.10.6. Resource requirements; and 9.2.4.10.7. Staffing levels. 9.2.4.11. A summary of the annual pretreatment budget, including costs of pretreatment program functions and equipment purchases. 9.2.4.12. A summary of public participation activities to involve and inform the public. 9.2.4.13. A description of any changes in sludge disposal methods and a discussion of any concerns not described elsewhere in the report. The pretreatment quarterly and annual reports shall be signed by a principal executive officer, CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-29 ranking elected official, or other duly authorized employee who is responsible for the overall operation of the Discharger (POTW - 40 C.F.R. section 403.12(m)). The Discharger shall submit signed copies of the reports to the State Water Board and the Regional Water Board electronically through the SMR module of CIWQS. Signed copies of the reports shall also be submitted electronically to U.S. EPA at R9Pretreatment@epa.gov or as instructed otherwise. 9.3. Salt and Nutrient Management Plan Reporting The previous Order required the Discharger to develop and implement an ongoing salts management plan dedicated to minimize the discharge of salts to and attainment of applicable water quality objectives (WQOs) for salts in San Luis Obispo Creek sub- basin of the Estero Bay Drainage Basin. Additionally, the previous order required the Discharger to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable WQOs for nutrients in the same basin. Based on the annual reports supplied by the Discharger, over the previous period of the Order, the Discharger has demonstrated that the effluent has contributed to exceedances of 2019 Basin Plan WQOs for salts. By February 1 of each year, the Discharger shall submit an annual report (separate from the NPDES annual report) describing salt and nutrient reduction efforts. The report shall include, at a minimum: 9.3.1. Salt Component 9.3.1.1. Calculations of annual salt mass discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; 9.3.1.2. Analysis of wastewater evaporation/salt concentration effects; 9.3.1.3. Analysis of groundwater monitoring results for salts constituents and associated trends; 9.3.1.4. Analysis of potential impacts of salt loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.1.5. A summary of existing salt reduction measures; and, 9.3.1.6. Recommendations and time schedules for implementation of any additional salt reduction measures. 9.3.2. Nutrient Component 9.3.2.1. Calculations of annual nitrogen mass (for all identified species) discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; 9.3.2.2. Analysis of wastewater treatment facility ability to facilitate nitrification and denitrification, or other means of nitrogen removal; 9.3.2.3. Analysis of groundwater monitoring results for nitrogen constituents and trends; CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-30 9.3.2.4. Analysis of potential impacts of nitrogen loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.2.5. A summary of existing nitrogen loading reduction measures; and, 9.3.2.6. Recommendations and time schedules for implementation of any additional nitrogen loading reduction measures. 9.4. Volumetric Monitoring of Wastewater and Recycled Water 9.4.1. Monthly volume of wastewater collected and treated by the wastewater treatment plant. 9.4.2. Monthly volume of wastewater treated, specifying level of treatment, including treated wastewater discharged. 9.4.3. Monthly volume of treated wastewater discharged, monthly volume of recycled water distributed for reuse, and annual volume of treated wastewater distributed for beneficial use in compliance with California Code of Regulations, title 22 use categories. 9.5 Discharge to Evaporation Ponds 9.5.1. The Discharger shall provide written notification to the Central Coast Water Board when there is any discharge to or from the Facility’s evaporation ponds, which are described in section 2.1 of the Fact Sheet. If the discharge is anticipated, the Discharger shall provide notice within 10 days prior to the anticipated discharge. If the discharge is unanticipated, the Discharger sh all provide notice within 24 hours of the time the discharge occurs. Discharge from the evaporation ponds is not permitted in this Order, so standard provision 5.5 applies. The notification must include discharge dates, times, volumes, and reasons for discharge. The notification must be submitted electronically, consistent with standard provision 5.10. 10. REPORTING REQUIREMENTS 10.1. General Monitoring and Reporting Requirements The Discharger shall comply with all Standard Provisions (Attachment D) related to monitoring, reporting, and recordkeeping. 10.2. Self-Monitoring Reports (SMRs) 10.2.1. The Discharger shall electronically submit SMRs using the State Water Board’s California Integrated Water Quality System (CIWQS) Program website (http://www.waterboards.ca.gov/water_issues/programs/ciwqs). The CIWQS website will provide additional information for SMR submittal in the event there will be a planned service interruption for electronic submittal. 10.2.2. The Discharger shall report in the SMR the results for all monitoring specified in this MRP under sections 3 through 9. The Discharger shall submit SMRs including the results of all required monitoring using U.S. EPA -approved test CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-31 methods or other test methods specified in this Order. SMRs are to include all new monitoring results obtained since the last SMR was submitted. If the Discharger monitors any pollutant more frequently than required by this Order, the results of this monitoring shall be included in the calculations and reporting of the data submitted in the SMR. 10.2.3. Monitoring periods and reporting for all required monitoring shall be completed according to the following schedule: Table E-10. Monitoring Periods and Reporting Schedule SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date NPDES Monitoring Report – Continuous, Daily, Weekly, Monthly MRP Sections 3 (Influent), 4 (Effluent) and 5 (Whole Effluent Toxicity), 9.5 Monthly First day of second calendar month following period of sampling Updated Toxicity Reduction Evaluation Work Plan Permit Section 6.3.2.1.1 Once 90 days following permit NPDES Monitoring Report - Quarterly MRP Sections 4 (Effluent) and 8.1 (Receiving Water) Quarterly May 1st August 1st November 1st February 1st NPDES Monitoring Report – Annually MRP Sections 4 (Effluent) and 8.1 (Receiving Water), 9.5 Annually February 15th Recycled Water Monitoring Report MRP Section 7.1 (Recycled Water Monitoring) Annually April 1st, the year following Recycled Water Volumetric Monitoring MRP Section 9.4 (Volumetric Reporting of Wastewater and Recycled Water) Annually April 30th, the year following sampling Note: This report is submitted using CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-32 SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date the GeoTracker system, not CIWQS Biosolids Monitoring Report MRP Section 9.1 (Biosolids Monitoring) Annually February 19th, the year following sampling Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Quarterly May 1st August 1st November 1st February 1st Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Annually February 15th, the year following sampling Summary Report Attachment D, Standard Provision, 8.4.8 (page D-16) Annually February 15th, the year following Salt and Nutrient Management Plan Annual Report MRP Section 9.3 (Salt and Nutrient Management Plan Reporting) Annually February 15th, the following year Pollutant Minimization Program Annual Report Permit Section 6.3.3.2 (Pollutant Minimization Program) Annually February 15th, the following year Climate Change Implementation Progress Report Permit Section 6.3.6.2 (Climate Change Adaptation Implementation Progress Report) Every five years May 1st, every five years following permit effective date. ROWD Application Permit renewal application Once per permit term 180 days prior to permit expiration date 10.2.4. Reporting Protocols. The Discharger shall report with each sample result the applicable Reporting Level (RL) and the current Method Detection Limit (MDL), as determined by the procedure in 40 C.F.R. part 136. The Discharger shall report the results of analytical determinations for the presence of chemical constituents in a sample using the following reporting protocols: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-33 10.2.4.1. Sample results greater than or equal to the RL shall be reported as measured by the laboratory (i.e., the measured chemical concentration in the sample). 10.2.4.2. Sample results less than the RL, but greater than or equal to the laboratory’s MDL, shall be reported as “Detected, but Not Quantified,” or DNQ. The estimated chemical concentration of the sample shall also be reported. For the purposes of data collection, the laboratory shall write the estimated chemical concentration next to DNQ. The laboratory may, if such information is available, include numerical estimates of the data quality for the reported result. Numerical estimates of data quality may be percent accuracy (± a percentage of the reported value), numerical ranges (low to high), or any other means considered appropriate by the laboratory. 10.2.4.3. Sample results less than the laboratory’s MDL shall be reported as “Not Detected,” or ND. 10.2.4.4. Dischargers are to instruct laboratories to establish calibration standards so that the ML value (or its equivalent if there is differential treatment of samples relative to calibration standards) is the lowest calibration standard. At no time is the Discharger to use analytical data derived from extrapolation beyond the lowest point of the calibration curve. 10.2.5. Compliance Determination. Compliance with effluent limitations for priority pollutants shall be determined using sample reporting protocols defined above and Attachment A. For purposes of reporting and administrative enforcement by the Central Coast Water Board and State Water Board, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the priority pollutant in the monitoring sample is greater than the effluent limitation and greater than or equal to the reporting level (RL). 10.2.6. Multiple Sample Data. When determining compliance with an AMEL, AWEL, or MDEL for priority pollutants and more than one sample result is available, the Discharger shall compute the arithmetic mean unless the data set contains one or more reported determinations of “Detected, but Not Quantified” (DNQ) or “Not Detected” (ND). In those cases, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 10.2.6.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 10.2.6.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 10.2.7. The Discharger shall submit SMRs in accordance with the following requirements: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-34 10.2.7.1. The Discharger shall arrange all reported data in a tabular format. The data shall be summarized to clearly illustrate whether the facility is operating in compliance with interim and/or final effluent limitations. The Discharger is not required to duplicate the submittal of data that is entered in a tabular format within CIWQS. When electronic submittal of data is required and CIWQS does not provide for entry into a tabular format within the system, the Discharger shall electronically submit the data in a tabular format as an attachment. 10.2.7.2. The Discharger shall attach a cover letter to the SMR. The information contained in the cover letter shall clearly identify violations of the waste discharge requirements; discuss corrective actions taken or planned; and the proposed time schedule for corrective actions. Identified violations must include a description of the requirement that was violated and a description of the violation. 10.2.7.3. The Discharger shall electronically self-report all violations of the waste- discharge requirements using the CIWQS self-reported violations function. 10.3. Discharge Monitoring Reports (DMRs) 10.3.1. DMRs are U.S. EPA reporting requirements. The Discharger shall electronically certify and submit DMRs together with SMRs using Electronic Self-Monitoring Reports module eSMR 2.5 or any upgraded version. Electronic DMR submittal shall be in addition to electronic SMR submittal. Information about electronic DMR submittal is available at the DMR website at: (http://www.waterboards.ca.gov/water_issues/programs/discharge_monitoring). 10.4. Other Reports 10.4.1. The Discharger shall report the results of any special studies, acute and chronic toxicity testing, TRE/TIE, and PMP, required by Special Provisions – 6.3. The Discharger shall report the progress in satisfaction of compliance schedule dates specified in Special Provisions – 6.3.7. The Discharger shall submit reports with the first monthly SMR scheduled to be submitted on or immediately following the report due date. 10.4.2. The Discharger shall report the volumetric monitoring requirements as specified in Other Monitoring Requirements - 9.4 to the State Water Board by April 30 of each calendar year. The Discharger shall electronically certify and submit this annual report containing the required data via the State Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. Information about the volumetric reporting of wastewater and recycled water and the Recycled Water Policy is available at the Recycled Water Policy Volumetric Annual Reporting website at http://www.waterboards.ca.gov/recycledwaterpolicy. 10.4.3. Every five years, the Discharger shall submit a Climate Change Implementation Progress Report as specified in section 6.3.6.2 of this Order. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-1 F. ATTACHMENT F – FACT SHEET TABLE OF CONTENTS 1. PERMIT INFORMATION .......................................................................................... F-3 2. FACILITY DESCRIPTION ........................................................................................ F-5 2.1. Description of Wastewater and Biosolids Treatment and Controls ........................ F-5 2.2. Discharge Points and Receiving Waters ............................................................... F-6 2.3. Summary of Existing Requirements and Self Monitoring Report Data .................. F-6 2.4. Summary of Interim Effluent Limits and Time Schedule Orders ............................ F-8 2.5. Compliance Summary ........................................................................................... F-9 2.6. Planned Changes ................................................................................................ F-10 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS ...................................... F-10 3.1. Legal Authorities.................................................................................................. F-11 3.2. California Environmental Quality Act (CEQA) ..................................................... F-11 3.3. State and Federal Laws, Regulations, Policies, and Plans ................................. F-11 3.4. Impaired Waterbodies on the CWA section 303(d) List ....................................... F-15 3.5. Other Plans, Polices and Regulations ................................................................. F-15 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS ................................................................................................................................... F-17 4.1. Discharge Prohibitions ........................................................................................ F-17 4.2. Technology-Based Effluent Limitations ............................................................... F-18 4.3. Water Quality-Based Effluent Limitations (WQBELs) .......................................... F-20 4.4. Final Effluent Limitation Considerations .............................................................. F-42 4.5. Interim Effluent Limitations – Not Applicable ....................................................... F-47 4.6. Land Discharge Specifications – Not Applicable ................................................. F-47 4.7. Recycling Specifications ...................................................................................... F-47 4.8. Point of Compliance for Effluent Limitations ........................................................ F-47 5. RATIONALE FOR RECEIVING WATER LIMITATIONS ........................................ F-48 5.1. Surface Water ..................................................................................................... F-48 6. RATIONALE FOR PROVISIONS ........................................................................... F-48 6.1. Standard Provisions ............................................................................................ F-48 6.2. Special Provisions ............................................................................................... F-48 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS .............. F-52 7.1. Influent Monitoring ............................................................................................... F-53 7.2. Effluent Monitoring .............................................................................................. F-53 7.3. Whole Effluent Toxicity Testing Requirements .................................................... F-53 7.4. Recycled Water Monitoring ................................................................................. F-54 7.5. Receiving Water Monitoring ................................................................................ F-54 7.6. Other Monitoring Requirements .......................................................................... F-55 9. PUBLIC PARTICIPATION ...................................................................................... F-58 9.1. Notification of Interested Persons........................................................................ F-58 9.2. Written Comments ............................................................................................... F-59 9.4. Reconsideration of Waste Discharge Requirements ........................................... F-59 9.5. Information and Copying ..................................................................................... F-59 9.6. Register of Interested Persons ............................................................................ F-60 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-2 9.7. Additional Information .......................................................................................... F-60 TABLE OF TABLES Table F-1. Facility Information ...................................................................................... F-3 Table F-2. Historic Effluent Limitations and Monitoring Data ........................................ F-7 Table F-3. TSO R3-2014-0036 Interim Effluent Limits ................................................. F-9 Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 ...... F-9 Table F-5. Basin Plan Beneficial Uses ....................................................................... F-12 Table F-6. Secondary Treatment Requirements ........................................................ F-19 Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 ................. F-19 Table F-8. Summary of RPA Results ......................................................................... F-23 Table F-9. Summary of Acute and Chronic Toxicity Test Results .............................. F-39 Table F-10. Final Effluent Limitations – Discharge Point EFF-001 ............................. F-44 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-3 ATTACHMENT F – FACT SHEET As described in section 2.2 of this Order, the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) incorporates this Fact Sheet as findings of the Central Coast Water Board supporting the issuance of this Order. This Fact Sheet includes the legal requirements and technical rationale that serve as the basis for the requirements of this Order. This Order has been prepared under a standardized format to accommodate a broad range of discharge requirements for dischargers in California. Only those sections or subsections of this Order that are specifically identified as “not applicable” have been determined not to apply to this Discharger. Sections or subsections of this Order not specifically identified as “not applicable” are applicable to this Discharger. 1. PERMIT INFORMATION The following table summarizes administrative information related to the facility. Table F-1. Facility Information WDID 3 400107001 Discharger City of San Luis Obispo Name of Facility City of San Luis Obispo Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Facility Contact, Title and Phone Patrick McGrath, WRRF Supervisor 805-781-7240 Authorized Person to Sign and Submit Reports Patrick McGrath, WRRF Supervisor 805-781-7240 Mailing Address 35 Prado Road, San Luis Obispo, CA 93401 Billing Address 35 Prado Road, San Luis Obispo, CA 93401 Type of Facility Publicly Owned Treatment Works (POTW) Major or Minor Facility Major Threat to Water Quality 2 Complexity A Pretreatment Program Yes CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-4 Recycling Requirements Production: NPDES R3-2024-0001 Distribution and Use: WQ 2016-0068, DDW Water Reclamation Requirements for Recycled Water Facility Permitted Flow 5.4 million gallons per day (MGD) Facility Design Flow 5.4 MGD Watershed Estero Bay Hydrologic Unit Receiving Water San Luis Obispo Creek Receiving Water Type Inland surface water 1.1. The City of San Luis Obispo (hereinafter Discharger or the City) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (hereinafter Facility), a publicly owned treatment works (POTW). For the purposes of this Order, references to the “discharger” or “permittee” in applicable federal and state laws, regulations, plans, or policy are held to be equivalent to references to the Discharger herein. 1.2. The Facility discharges wastewater to San Luis Obispo Creek, a water of the United States. 1.3. When applicable, state law requires dischargers to file a petition with the State Water Resources Control Board (State Water Board), Division of Water Rights and receive approval for any change in the point of discharge, place of use, or purpose of use of treated wastewater that decreases the flow in any portion of a watercourse. The State Water Board retains separate jurisdictional a uthority to enforce any applicable requirements under California Water Code section 1211. This is not an NPDES permit requirement. 1.4. The Discharger was previously regulated by Order R3-2014-0033 and National Pollutant Discharge Elimination System (NPDES) Permit CA0049224 adopted on September 25, 2014, and effective on December 1, 2014. The Discharger was also regulated by Time Schedule Order R3-2014-0036 and Time Schedule Order R3- 2019-0124. The Discharger filed a Report of Waste Discharge (ROWD) and submitted an application for reissuance of its waste discharge requirements (WDRs) and NPDES permit on May 28, 2019. 1.5. The Discharger was previously regulated by Waste Discharge Requirements and Master Reclamation Requirements Order R3-2003-081, which authorized the production, distribution, and use of recycled water. 1.6. Federal regulations at 40 C.F.R. section 122.46 limit the duration of NPDES permits to a fixed term not to exceed five years. However, pursuant to California Code of Regulations, title 23, section 2235.4, the terms and conditions of an expired permit are automatically continued pending reissuance of the permit if the Discharger complies with all federal NPDES requirements for continuation of expired permits. Because the Discharger met the requirements of California Code of Regulations, title 23, section 2235.4, Order No. R3-2014-0033, NPDES Permit No. CA0049224 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-5 was administratively continued after the original expiration date of November 30, 2019. 2. FACILITY DESCRIPTION 2.1. Description of Wastewater and Biosolids Treatment and Controls The City of San Luis Obispo Resource Recovery Facility is a municipal wastewater collection, treatment, and disposal facility that discharges tertiary treated wastewater to San Luis Obispo Creek. First constructed in 1920 and located at the southwest corner of the City of San Luis Obispo and adjacent to San Luis Obispo Creek, the Facility provides sewerage service to approximately 47,328 municipal and industrial users from the City of San Luis Obispo, California Polytechnic State University, San Luis Obispo, and the San Luis Obispo County Regional Airport. The City also administers an approved pretreatment program that includes seven significant industrial users, as defined in federal regulations. The Discharger currently operates a collection system that is composed of over 148 miles of main line and 9 lift stations. The design flow capacity of the Facility is 5.4 MGD. During storm events, the estimated wet weather influent flow to the facility is 11.1 MGD due to inflow and infiltration into the collection system from aging or broken/cracked pipes. Ongoing capital improvement projects for sewer line replacement, flow metering, and main line repairs will continue to address areas of concern that result in inflow and infiltration into the Facility. The Discharger has been implementing a significant upgrade of the Facility’s biological, disinfection, and biosolids units since 2019. A focus of the facility upgrade was to improve removal of chorine disinfection byproducts (trihalomethanes, or THMs) and nitrate to meet effluent limits of the previous permit. Another focus of the upgrade was to increase the facility’s ability to treat high inflows from wet-weather events. Prior to the most recent upgrades, the facility’s treatment process consisted of an equalization basin, mechanical screening, grit removal, primary settling, biofiltration, secondary settling, nitrification with two activated sludge aeration basins, final settling, cooling using evaporative cooling towers, dual media filtration, and chlorination/dechlorination. During the upgrade, the discharger removed or abandoned the following components of the facility: bio filter and secondary clarifier, final clarifiers, tertiary dual media filtration, and chlorine disinfection and dechlorination. The two activated sludge basins were converted to Modified Ludzack-Ettinger (MLE) bioreactors for nutrient removal, the dissolved air floatation thickener (DAFT) was modified into a sludge blend tank, and a digester was modified into an odor control unit. The final upgraded treatment system currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four MLE bioreactors, hollowfiber membranes, and UV disinfection. Although chlorination and dechlorination of the effluent and recycled water has been terminated due to the use of UV disinfection, the recycled water sent to the storage tank will be dosed with chlorine to maintain a chlorine residual in the recycled water distribution line per best practices of the distribution system. The Discharger may use sodium hypochlorite (chlorine) for CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-6 maintenance purposes such as membrane cleaning in the MLE unit when hydrogen peroxide and/or citric acid is insufficient. If chlorine is used for membrane cleaning, dechlorination of the effluent with sodium bisulfite may be necessary remove the chlorine residual to protect beneficial uses of San Luis Obispo Creek. Biosolids were previously handled with a dissolved air floatation thickener (DAFT), three anaerobic digesters, a screw press, a belt filter press, and drying beds, with the final product shipped out for composting. The upgraded biosolids handling train now consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, a digested sludge storage tank, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. There are two lined evaporation ponds located at southwest corner of the Facility property. The Discharger has occasionally diverted wastewater to these ponds when it did not meet effluent limitations, rather than discharging the wastewater to the creek. This Order requires the Discharger to submit a written notification to the Central Coast Water Board when wastewater is sent to these ponds. This Order does not provide regulatory coverage for the discharge of wastewater from these ponds to land or surface water. In recent years with large, prolonged storm events, these ponds have filled with stormwater from overland flow (not from the facility). This Order does not provide coverage of stormwater discharge from these ponds. As discussed further in section 3.5.1 of this Fact Sheet, the Discharger is enrolled in the Industrial General Permit (State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001). The Discharger may incorporate these ponds into their Industrial General Permit enrollment to allow for the discharge of stormwater from the ponds, in compliance with all the requirements of the Industrial General Permit. 2.2. Discharge Points and Receiving Waters Tertiary treated wastewater is discharged from Discharge Point EFF-001 to San Luis Obispo Creek, a water of the United States, at latitude 35.244307° N and longitude 120.680618° W. Sampling location EFF-001A is located prior to discharge into the effluent pipeline that discharges to San Luis Obispo Creek. Sampling location EFF-001B is located at the most downstream end of the effluent pipeline that discharges to San Luis Obispo creek. The flowrate in San Luis Obispo Creek varies greatly between the wet and dry seasons. No dilution credit has been granted for this discharge. Tertiary treated wastewater is discharged from Discharge Point EFF-002 to the Discharger’s reclaimed water storage tank that is located just south of the UV disinfection system. The reclaimed water storage tank feeds the Discharger’s reclaimed water distribution lines located throughout the city. 2.3. Summary of Existing Requirements and Self Monitoring Report Data Effluent limitations contained in Order R3-2014-0033 for discharges from Discharge Point 001 (Monitoring Location EFF-001) and representative monitoring data from December 1, 2014, to December 1, 2022, are shown in Table F-2: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-7 Table F-2. Historic Effluent Limitations and Monitoring Data Parameter Units Averag e Monthl y Effluen t Limit Averag e Weekly Effluen t Limit Maximum Daily Effluent Limit Highest Average Monthly Discharge Reported Highest Average Weekly Discharge Reported Highest Daily Discharge Reported Flow (dry weather) MGD 5.1 --- --- 8.0 --- 12.9[1] Biochemical Oxygen Demand 5- day @ 20°C (BOD5) milligra ms per liter (mg/L) 10 30 50 8.84 14.3 12.6 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) pounds per day (lbs/day ) 425 1275 2125 382 382 382 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) percent removal ≥85 --- --- 91.6 – 100[2] Total Suspended Solids (TSS) mg/L 10 30 75 7.9 11 23.3 Total Suspended Solids (TSS) lbs/day 425 1275 3190 572 842 1556 Total Suspended Solids (TSS) percent removal ≥85 --- --- 97.3-99.7[2] --- --- Oil and Grease mg/L 5 --- 10 8 --- 8 Settleable Solids milliliter per liter per hour (mL/L/h r) 0.1 --- --- <0.1 --- --- pH standar d units 6.5– 8.3[3] 6.5 – 7.88[4] Nitrate, Total (as N) mg/L 10 --- --- 51.7 --- --- Chlorodibro momethane µg/L 0.4 --- 1.0 5 --- 5 Dichlorobro momethane µg/L 0.56 --- 1.0 22 --- 22 N- Nitrosodimet hylamine µg/L 0.0006 9 --- 0.0014 ND --- ND Dissolved Oxygen mg/L 4.0[5] 4.8 CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-8 Chlorine Residual mg/L --- --- ND[6] --- --- 0.76 Chronic Toxicity Toxic Units Chronic (TUc) --- --- 1.0 --- --- 4.0 Fecal or Total Coliform Bacteria Most probabl e number (MPN)/ 100 mL [7] [8] [9] 79, 94[10] 1.8 350 [1] Reported as maximum daily. Flow occurred in February 2017 during a wet weather event. [2] The numbers represent the range of lowest to highest reported values. [3] Applied as an instantaneous minimum and maximum effluent limitation. [4] Representative values contain the lowest instantaneous minimum to the highest instantaneous maximum. [5] Applied as an instantaneous minimum effluent limitation. [6] ND = less than 0.1 mg/L. Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [7] No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 -day period. [8] The median number of fecal coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days for which analyses have been completed. [9] The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [10] Values occurred within a 30-day time period. 2.4. Summary of Interim Effluent Limits and Time Schedule Orders During the permit term for Order R3-2014-0036, the discharger could not immediately achieve compliance with the chlorodibromomethane, dichlorobromomethane, and nitrate effluent limitations. The Central Coast Water Board issued two time schedule orders (TSOs) to set interim effluent limits and compliance timelines: TSO R3-2014- 0036 and TSO R3-2019-0124. TSO R3-2014-0036 set interim limits for the three aforementioned effluent limits with full compliance with effluent limits by November 30, 2019. With the planned upgrades to the Facility’s biological and disinfection units, TSO R3-2019-0124 extended the deadlines to meet the interim effluent limits with a compliance deadline of March 31, 2020, for chlorodibromomethane and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-9 dichlorobromomethane and a compliance deadline of July 31, 2023 for nitrate. Table F- 3 summarizes the interim effluent limits that were established. The interim effluent limitations were established based on the Facility’s performance. When operating under a TSO, if effluent concentrations exceed the final effluent limitation but do not exceed the interim effluent limitation, an effluent violation has not occurred, and mandatory minimum penalties do not apply. If effluent concentrations exceed both the final and interim effluent limitation values, then an effluent violation has occurred, and mandatory minimum penalties do apply. Table F-3. TSO R3-2014-0036 Interim Effluent Limits Constituent Units Average Monthly Maximum Daily Chlorodibromomethane µg/L - 42 Dichlorobromomethane µg/L - 36 Nitrate (as Nitrogen) mg/L 42.6 - 2.5. Compliance Summary 2.5.1 Effluent Compliance Summary The following discussion is a summary of the violations that occurred during the term and administrative extension of Order No. R3-2014-0033. During the time period from December 1, 2014, to May 31, 2023, the Discharger incurred effluent violations related to nitrate, oil and grease, total coliform, chlorine residual, dichlorobromomethane, and chlorodibromomethane. The number of violations, violation type, and reported value range are provided in Table F-4. Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Nitrate (Total as N) December 2016- November 2022 Monthly Average (Mean) Limit 9 43.2-51.7 10 mg/L Oil and Grease March 2017 Monthly Average Limit 1 6 5 mg/L CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-10 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Total Coliform July 2018- October 2020 30-Day Specific Limit 3 33-1600 23 MPN/ 100m L Total Coliform December 2019- October 2020 Daily Maximum 3 540-1600 240 MPN/ 100m L Residual Chlorine February 2020- December 2022 Daily Maximum 2 0.35-0.75 ND mg/L Dichlorobro momethane April 2020- October 2022 Monthly Average Limit 4 2.5-17.8 0.56 µg/L Dichlorobro momethane April 2020- October 2022 Daily Maximum 4 2.5-17.8 1 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Monthly Average Limit 3 1.2-5 0.40 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Daily Maximum 3 1.2-5 1 µg/L 2.6. Planned Changes The Discharger will continue to implement planned upgrades through 2024. The Discharger has not indicated it plans any significant changes to the Facility beyond those during the term of the Order. 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS The requirements contained in this Order are based on the requirements and authorities described in this section. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-11 3.1. Legal Authorities This Order serves as WDRs pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA), implementing regulations promulgated by the U.S. Environmental Protection Agency (U.S. EPA), and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as an NPDES permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1, subject to the WDRs in this Order. 3.2. California Environmental Quality Act (CEQA) Under California Water Code section 13389, this action to adopt an NPDES permit for an existing facility is exempt from the California Environmental Quality Act (CEQA) provisions in Public Resources Code, division 13, chapter 3 (commencing with section 21100). With respect to the recycling specifications and groundwater limitations, this action is exempt from the provisions of CEQA pursuant to title 14, California Code of Regulations, section 15301, class 1 exemption for permitting of existing facilities with no expansion of existing use. 3.3. State and Federal Laws, Regulations, Policies, and Plans 3.3.1. Water Quality Control Plan. The Central Coast Water Board adopted the Water Quality Control Plan for the Central Coastal Basin (Basin Plan), which designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for all waters addressed through the plan. Requirements in this Order implement the Basin Plan. In addition, the Basin Plan implements State Water Board Resolution 88 -63, which established state policy that all waters, with certain exceptions, should be considered suitable or potentially suitable for municipal or domestic supply. Beneficial uses established by the 2019 Basin Plan for San Luis Obispo Creek (below W. Marsh Street) are presented below: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-12 Table F-5. Basin Plan Beneficial Uses Discharge Point Receiving Water Name Beneficial Use(s) 001 San Luis Obispo Creek (below W. Marsh Street) Existing: Municipal and Domestic Supply (MUN); Agricultural Supply (AGR); Ground Water Recharge (GWR); Water Contact Recreation (REC-1); Non-Contact Water Recreation (REC-2); Wildlife Habitat (WILD); Cold Freshwater Habitat (COLD); Warm Freshwater Habitat (WARM); Migration of Aquatic Organisms (MIGR) Spawning, Reproduction, and/or Early Development (SPWN); Fresh Water Replenishment (FRSH) Commercial and Sport Fishing (COMM). Intermittent: None. Potential: None. Groundwater throughout the Central Coast Region has designated beneficial uses of agricultural water supply, municipal and domestic water supply, and industrial use. Requirements of this Order implement the Basin Plan. 3.3.2. Thermal Plan. The State Water Board adopted the Water Quality Control Plan for Control of Temperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of California (Thermal Plan) January 7, 1971, and amended the plan on September 18, 1975. This plan contains temperature objectives for surface waters. Requirements of this Order implement the Thermal Plan. 3.3.3. Sediment Quality. The State Water Board adopted the Water Quality Control Plan for Enclosed Bays and Estuaries – Part 1, Sediment Quality on September 16, 2008, and it became effective on August 25, 2009. This plan supersedes other narrative sediment quality objectives and establishes new sediment quality objectives and related implementation provisions for specifically defined sediments in most bays and estuaries. Requirements of this Order implement sediment quality objectives of this plan. 3.3.4. National Toxics Rule (NTR) and California Toxics Rule (CTR). U.S. EPA adopted the NTR on December 22, 1992, and later amended it on May 4, 1995 , and November 9, 1999. About forty criteria in the NTR apply in California. On May 18, 2000, U.S. EPA adopted the CTR. The CTR promulgated new toxics criteria for California and, in addition, incorporated the previously adopted NTR criteria CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-13 that were applicable in the state. The CTR was amended on February 13, 2001. These rules contain federal water quality criteria for priority pollutants. 3.3.5. State Implementation Policy. On March 2, 2000, the State Water Board adopted Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (State Implementation Policy or SIP). The SIP became effective on April 28, 2000, with respect to the priority pollutant criteria promulgated for California by the U.S. EPA through the NTR and to the priority pollutant objectives established by the Central Coast Water Board in the Basin Plan. The SIP became effective on May 18, 2000, with respect to the priority pollutant criteria promulgated by the U.S. EPA through the CTR. The State Water Board adopted amendments to the SIP on February 24, 2005, that became effective on July 13, 2005. 3.3.6 Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (ISWEBE Plan). The ISWEBE Plan includes several parts and sections that have been adopted by the State Water Board over time. The applicable parts and sections are discussed below. On May 2, 2017, the State Water Board adopted and ISWEBE Plan Part 2: Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. With ISWEBE Plan Part 2’s approval, the State Water Board approved one new narrative and four new numeric mercury water quality objectives to apply to those inland surface waters, enclosed bays, and estuaries of the state that have any of the following beneficial use designations: COMM, CUL, T-SUB, WILD, MAR, RARE, WARM, COLD, EST, or SAL. The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On August 7, 2018, the State Water Board adopted ISWEBE Plan Part 3: Bacteria Provisions and a Water Quality Standards Variance Policy, which establishes water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On December 1, 2020, the State Water Board adopted the Aquatic Toxicity Provisions, which are incorporated into the ISWEBE Plan. On October 5, 2021, the State Water Board adopted a resolution to confirm that the Aquatic Toxicity Provisions were adopted as state policy for water quality control for all inland surface waters, enclosed bays, estuaries, and coastal lagoons of the state. The provisions were approved by the California Office of Administrative Law on April 25, 2022 and were approved by the U.S. EPA on May 1, 2023. The provisions include statewide numeric water quality objectives for both acute and chronic toxicity and a program of implementation to control toxicity. The provisions provide consistent protection of aquatic life beneficial uses in inland surface waters, enclosed bays, estuaries, and coastal lagoons throughout the state from the effects of known and unknown toxicants. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-14 This Order is consistent with the ISWEBE Plan and includes effluent limitations for mercury, bacteria, and chronic toxicity. 3.3.6. Domestic Water Quality. In compliance with California Water Code section 106.3, it is the policy of the State of California that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. This Order promotes that policy by requiring discharges to meet water quality objectives established in the Basin Plan that are based on drinking water maximum contaminant levels and designed to protect human health and ensure that water is safe for domestic use. 3.3.7. Antidegradation Policy. Federal regulation 40 C.F.R. section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal policy. The State Water Board established California’s antidegradation policy in State Water Board Resolution 68-16, Statement of Policy with Respect to Maintaining High Quality of Waters in California . Resolution 68-16 is deemed to incorporate the federal antidegradation policy where the federal policy applies under federal law. Resolution 68-16 requires that existing water quality be maintained unless degradation is justified by specific findings. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The permitted discharge must be consistent with the antidegradation provision of 40 C.F.R. section 131.12 and State Water Board Resolution 68-16. 3.3.8. Anti-Backsliding Requirements. Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. section 122.44(l) restrict backsliding in NPDES permits. These anti-backsliding provisions require that effluent limitations in a reissued permit must be as stringent as those in the previous permit, with some exceptions in which limitations may be relaxed. 3.3.9. Endangered Species Act Requirements. This Order does not authorize any act that results in the taking of a threatened or endangered species or any act that is now prohibited, or becomes prohibited in the future, under either the California Endangered Species Act (Fish and Game Code sections 2050 to 2097) or the Federal Endangered Species Act (16 U.S.C. sections 1531 to 1544). This Order requires compliance with effluent limits, receiving water limits, and other requirements to protect the beneficial uses of waters of the state. The Discharger is responsible for meeting all applicable requirements of the endangered species acts. 3.3.10. Sewage Sludge and Biosolids. This Order does not authorize any act that results in violation of requirements administered by U.S. EPA to implement 40 C.F.R. part 503, Standards for the Use or Disposal of Sewage Sludge. These standards regulate the final use or disposal of sewage sludge that is generated during the treatment of domestic sewage in a municipal wastewater treatment facility. The Discharger is responsible for meeting all applicable requirements of 40 C.F.R. part 503 that are under U.S. EPA’s enforcement authority. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-15 3.4. Impaired Waterbodies on the CWA section 303(d) List CWA section 303(d) requires states to identify and make a list of specific water bodies where water quality standards are not expected to be met after implementation of technology-based effluent limitations on point sources. For all CWA section 303(d) listed water bodies and pollutants, the Central Coast Water Board must develop and implement total maximum daily loads (TMDLs) that specify waste load allocations (WLAs) for point sources and load allocations (LAs) for non- point sources. The U.S. EPA approved the State’s 2020-2022 303(d) list of impaired water bodies on May 11, 2022. The 2020-2022 303(d) list identifies San Luis Obispo Creek, below Osos Street, as impaired for chloride, sodium, benthic community effects, Escherichia coli (E. coli), dissolved oxygen, nitrate, and toxicity. A TMDL for nitrate was adopted for San Luis Obispo Creek below West Marsh Street. Effluent limitations for nitrate in this Permit are based on Central Coast Water Board Resolution R3-2005-0106 (TMDL for nitrate). A TMDL for pathogens was adopted for San Luis Obispo Creek (R3-2004-0142) but the Facility was not identified as a source and was not assigned a wasteload allocation. However, the Discharger is implementing a Wasteload Allocation Attainment Plan (WAAP) to address pathogens from the sources identified in the TMDL. 3.5. Other Plans, Polices and Regulations 3.5.1. State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001, Waste Discharge Requirements for Stormwater Associated with Industrial Activities Excluding Construction Activities (Industrial General Permit). The Industrial General Permit, adopted April 1, 2014, amended August 4, 2015, and November 6, 2018, and effective July 1, 2015, is applicable to POTWs with a design capacity greater than 1.0 MGD. The purpose of the Industrial General Order is to regulate stormwater discharges associated with industrial activities. For the control of stormwater discharged from the Facility, the Discharger has enrolled in and is regulated by the Industrial General Permit. 3.5.2. State Water Board Order. 2022-0103-DWQ Statewide General Waste Discharge Requirements for Sanitary Sewer Systems. State Water Board Order No. 2022-0103-DWQ, adopted on December 6, 2022, is applicable to all "federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California." The purpose of Water Quality Order 2022-0103-DWQ is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled in Water Quality Order 2022-0103-DWQ and must comply with its requirements and any requirements in reissuances to Water Quality Order 2022-0103-DWQ. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-16 3.5.3. State Water Board Recycled Water Policy. The State Water Board adopted the Quality Control Policy for Recycled Water (Recycled Water Policy) on December 11, 2018, and it became effective on April 8, 2019. The purpose of the Recycled Water Policy is to encourage the safe use of recycled water in a manner that is protective of public health and the environment. This Order implements the Recycled Water Policy by supporting the production of recycled water and requiring volumetric reporting of wastewater and recycled water to the State Water Board. The Recycled Water Policy calls for the development of regional groundwater basin/sub-basin salt/nutrient management plans. This Order requires the Discharger to continue to commit funding and in-kind resources to facilitate development of a regional groundwater basin/sub-basin salt/nutrient management plan that implements the Recycled Water Policy. 3.5.4 Statewide General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW). State Water Board Order WQ 2016-0068-DDW, adopted on June 7, 2016, is applicable to recycled water projects where recycled water is used or transported for non -potable uses. The distribution and offsite reuse of recycled water produced by the Facility is subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. 3.5.5 Environmental Justice and Advancing Racial Equity. When issuing or reissuing individual waste discharge requirements or waivers of waste discharge requirements that regulate an activity or a facility that may impact a disadvantaged or tribal community, and that includes a time schedule in accordance with subdivision (c) of Section 13263 for achieving an applicable water quality objective, an alternative compliance path that allows time to come into compliance with water quality objectives, or a water quality variance, the Central Coast Water Board shall make a finding on potential environmental justice, tribal impact, and racial equity considerations. (Water Code § 13149.2, effective Jan. 1, 2023). Water Code section 189.7 requires the Central Coast Water Board to conduct outreach in disadvantaged and/or tribal communities when adopting individual waste discharge requirements. In accordance with the Water Boards’ efforts to advance racial equity, the Central Coast Water Board is also committed to developing and implementing policies and programs to advance racial equity and environmental justice so that race can no longer be used to predict life outcomes, and outcomes for all groups are improved. Upon review of readily available information, the Central Coast Water Board finds that this Order regulates a discharge that does not disproportionately impact the water quality of an economically disadvantaged community or a tribal community. Similarly, this Order does not include a time schedule, alternative compliance path, or variance. Therefore, Water Code section 13149.2 does not apply to this permit reissuance. Nevertheless, the Central Coast Water Board has conducted outreach consistent with Water Code section 189.7 by reaching out to surrounding communities and tribal communities about this Order. Additionally, the Board has considered any environmental justice concerns within the Board’s authority, in accordance with the Water Boards’ efforts to advance racial equity. The Order CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-17 requires the Permittee to meet water quality standards to protect public health and the environment, thereby benefiting all persons and communities within the Region. 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS The CWA requires point source dischargers to control the amount of conventional, non-conventional, and toxic pollutants that are discharged into the waters of the United States. The control of pollutants discharged is established through effluent limitations and other requirements in NPDES permits. There are two principal bases for effluent limitations in the Code of Federal Regulations: 40 C.F.R. section 122.44(a) requires that permits include applicable technology-based limitations and standards, and 40 C.F.R. section 122.44(d) requires that permits include water quality-based effluent limitations to attain and maintain applicable numeric and narrative water quality criteria to protect the beneficial uses of receiving waters. When numeric water quality objectives have not been established, but a discharge has the reasonable potential to cause or contribute to exceedances of water quality standards described at 40 C.F.R. section 122.44 (d), then 1) water quality based effluent limitations (WQBELS) may be established using a calculated water quality criterion derived from a proposed state criterion or an explicit State policy or regulation interpreting its narrative criterion, 2) WQBELs may be established on a case-by-case basis using U.S. EPA criteria guidance published under CWA Section 304 (a), or 3) WQBELs may be established using an indicator parameter for the pollutant of concern. Several specific factors affecting the development of limitations and requirements in this Order are discussed below. 4.1. Discharge Prohibitions 4.1.1. Discharge Prohibition 3.1. (No discharge at a location or in a manner except as described by the Order). The Order authorizes a single, specific point of discharge to surface waters, and the limitations and conditions established by the Order are based on specific information provided by the Discharger and gained by the Central Coast Water Board through site visits, review of monitoring reports, and other information. Discharges to surface waters at locations not contemplated by this Order or discharges of a character not contemplated by this Order are therefore viewed as inconsistent with CWA section 402’s prohibition against discharges of pollutants except in compliance with the CWA’s permit requirements, effluent limitations, and other enumerated provisions. This prohibition is retained from the previous permit. 4.1.2. Discharge Prohibition 3.2. (Discharge of any waste not specifically regulated by this Order is prohibited). Because limitations and conditions of the Order are based on specific information provided by the Discharger and specific wastes described by the Discharger, the limitations and conditions of the Order do not adequately address waste streams not contemplated during drafting of the Order. To prevent the discharge of such waste streams that may be inadequately CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-18 regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.1.3. Discharge Prohibition 3.3. (Overflow, bypass, or overspray of wastewater from the Discharger’s facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7. (Bypass), is prohibited). The discharge of untreated or partially treated wastewater from the Discharger’s collection, treatment, or disposal facilities represents an unauthorized bypass pursuant to 40 C.F.R. section 122.41(m) or an unauthorized discharge that poses a threat to human health and/or aquatic life, and, therefore, is explicitly prohibited by this Order. 4.1.4. Discharge Prohibition 3.4. (Creation of a condition of pollution, contamination, or nuisance, as defined by Section 13050 of the California Water Code, is prohibited). The Basin Plan requires that the disposal of wastewater to waterbodies be accomplished in a manner that safeguards public health and prevents nuisance conditions. 4.1.5. Discharge Prohibition 3.5. (Discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat). This prohibition is consistent with the requirements of the Basin Plan. 4.1.6. Discharge Prohibition 3.6. (Discharge of radioactive substances is prohibited). This prohibition is consistent with the requirements of the Basin Plan. 4.1.7. Discharge Prohibition 3.7. (Monthly average dry weather effluent flow shall not exceed 5.4 million gallons per day (MGD), aggregated at Discharge Point 001). To prevent the discharge of such waste streams that may be inadequately regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.2. Technology-Based Effluent Limitations 4.2.1. Scope and Authority Section 301(b) of the CWA and implementing U.S. EPA permit regulations at 40 C.F.R. § 122.44 require that permits include conditions meeting applicable technology-based requirements at a minimum, and any more stringent effluent limitations necessary to meet applicable water quality standards. Where the USEPA has not yet developed technology-based standards for a particular industry or a particular pollutant, CWA Section 402 (a) (1) and USEPA regulations at 40 C.F.R. § 125.3 authorize the use of best professional judgment (BPJ) to derive technology-based effluent limitations on a case-by-case basis. When BPJ is used, the permit writer must consider specific factors outlined at 40 C.F.R. § 125.3. Regulations promulgated in 40 C.F.R. § 125.3(a)(1) require technology- based effluent limitations for municipal dischargers to be placed in NPDES permits based on Secondary Treatment Standards or Equivalent to Secondary Treatment Standards. The Federal Water Pollution Control Act Amendments of 1972 (PL 92-500) established the minimum performance requirements for POTWs [defined in section 304(d)(1)]. Section 301(b)(1)(B) of that act requires CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-19 that such treatment works must, as a minimum, meet effluent limitations based on secondary treatment as defined by the U.S. EPA Administrator. Based on this statutory requirement, U.S. EPA developed secondary treatment regulations, which are specified in 40 C.F.R. part 133. These technology-based regulations apply to all municipal wastewater treatment plants and identify the minimum level of effluent quality attainable by secondary treatment in terms of biochemical oxygen demand (BOD5), total suspended solids (TSS), and pH. The discharge authorized by this Order must meet minimum federal technology-based requirements based on Secondary Treatment Standards at 40 C.F.R. part 133 , summarized below: Table F-6. Secondary Treatment Requirements Parameter Units 30-Day Average 7-Day Average BOD5 [1] mg/L 30 45 TSS[1] mg/L 30 45 pH standard units 6.0[2] 9.0[3] [1] The 30-day average percent removal shall not be less than 85 percent. [2] Instantaneous minimum value. [3] Instantaneous maximum value. 4.2.2. Applicable Technology-Based Effluent Limitations 40 C.F.R. section122.45(f)(1) requires effluent limitations be expressed in terms of mass, with some exceptions, and 40 C.F.R. section 122.45(f)(2) allows pollutants that are limited in terms of mass to additionally be limited in terms of other units of measurement. This Order includes effluent limitations expressed in terms of mass and concentration. In addition, pursuant to the exceptio ns to mass limitations provided in 40 C.F.R. section 122.45(f)(1), some effluent limitations are not expressed in terms of mass, such as pH and temperature, as well as when the applicable standards are expressed in terms of concentration and mass limitations are not necessary to protect the beneficial uses of the receiving waters. 4.2.2.1. The following table summarizes technology-based effluent limitations established by this Order at Discharge Point 001. Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 Parameter Units 30-Day Average 7-Day Average Maximum Daily BOD5[1] mg/L 10 30 50 BOD5 lbs/day [2] 450 1,351 2,252 Total Suspended Solids (TSS)[1] mg/L 10 30 75 TSS lbs/day[2] 450 1,351 3,378 [1] The average monthly percent removal of BOD5 and TSS, as measured at Monitoring Location EFF-001, shall not be less than 85 percent. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-20 [2] Mass loading limits were calculated using the following formulas: lbs/day = pollutant concentration (mg/L) * permitted flow (5.4 MGD) * conversion factor (8.34) [3] Instantaneous minimum value. [4] Instantaneous maximum value. 4.2.2.1.1. BOD5 and TSS. BOD and TSS. Federal regulations, 40 C.F.R. part 133, establish the minimum weekly and monthly average level of effluent quality attainable by secondary treatment for BOD5 and TSS. The Central Coast Water Board has determined that tertiary treatment is necessary to protect the beneficial uses of the receiving stream, thus the final effluent limitations for BOD5 and TSS are based on the technical capability of the tertiary process. The secondary and tertiary treatment standards for BOD5 and TSS are indicators of the effectiveness of the treatment processes. The principal design parameter for wastewater treatment plants is the daily BOD5 and TSS loading rates and the corresponding removal rate of the system. In applying 40 C.F.R. part 133 for weekly and monthly average BOD5 and TSS limitations, the application of tertiary treatment processes results in the ability to achieve lower levels for BOD5 and TSS than the secondary standards currently prescribed; the 30 -day average BOD5 and TSS limitations are 10 mg/L, the 7-day average BOD5 and TSS limitations are 30 mg/L. These effluent limitations are based on the capability of a tertiary system. In addition to the average weekly and average monthly effluent limitations, daily maximum effluent limitation of 50 mg/L and 75 mg/L for BOD5 and TSS, respectively, are included in the Order to ensure that the treatment works are not organically overloaded and operate in accordance with design capabilities. In addition, 40 C.F.R. § 133.102, in describing the minimum level of effluent quality attainable by secondary treatment, states that the 30-day average percent removal shall not be less than 85 percent. If 85 percent removal of BOD5 and TSS must be achieved by a secondary treatment plant, it must also be achieved by a tertiary (i.e., treatment beyond secondary level) treatment plant. This Order contains a limitation requiring an average of 85 percent removal of BOD5 and TSS over each calendar month. These effluent limitations are carried over from Order R3-2014-0033. 4.3. Water Quality-Based Effluent Limitations (WQBELs) 4.3.1. Scope and Authority CWA section 301(b) and 40 C.F.R. section 122.44(d) require that permits include limitations more stringent than applicable federal technology -based requirements where necessary to achieve applicable water quality standards. Section 122.44(d)(1)(i) of 40 C.F.R. requires that permits include effluent limitations for all pollutants that are or may be discharged at levels that have the reasonable potential to cause or contribute to an exceedance of a water quality standard, including numeric and narrative objectives within a standard. Where reasonable potential has been established for a pollutant, but there is no numeric criterion or objective for the pollutant, WQBELs must be established using: (1) U.S. EPA criteria guidance under CWA section 304(a), supplemented where CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-21 necessary by other relevant information; (2) an indicator parameter for the pollutant of concern; or (3) a calculated numeric water quality criterion, such as a proposed state criterion or policy interpreting the state’s narrative criterion, supplemented with other relevant information, as provided in section 122.44(d)(1)(vi). The process for determining reasonable potential and calculating WQBELs when necessary is intended to protect the designated uses of the receiving water as specified in the Basin Plan and to achieve applicable water quality objectives and criteria that are contained in other state plans and policies, or any applicable water quality criteria contained in the CTR and NTR. 4.3.2. Applicable Beneficial Uses and Water Quality Criteria and Objectives Beneficial uses described by the 2019 Basin Plan for San Luis Obispo Creek and they are presented in section 3.3.1 of this Fact Sheet. Water quality criteria applicable to this receiving water are established by the CTR, the NTR, and by the 2019 Basin Plan. 4.3.3. Determining the Need for WQBELs NPDES regulations at 40 CFR section 122.44(d) require effluent limitations to control all pollutants which are or may be discharged at a level which will cause, have the reasonable potential to cause, or contribute to an excursion above any State water quality standard. The SIP, the statewide policy that became effective on May 22, 2000, establishes procedures to implement water quality criteria from the NTR and CTR and for priority, toxic pollutant objectives established in the Basin Plan. The implementation procedures of the SIP include methods to determine reasonable potential (for pollutants to cause or contribute to excursions above State water quality standards) and to establish numeric effluent limitations, if necessary, for those pollutants which show reasonable potential. The SIP Section 1.3 requires the Central Coast Water Board to use all available valid, relevant, and representative receiving water and effluent data and information to conduct a reasonable potential analysis (RPA). The Central Coast Water Board analyzed the Discharger’s data for priority pollutants and the nature of the discharge to determine if the discharge has reasonable potential to exceed water quality standards. The RPA is based on effluent data retrieved from CIWQS from the period of December 2014 to December 2022. Some freshwater water quality criteria for metals are hardness dependent, i.e., as hardness decreases, the toxicity of certain metals increases, and the applicable water quality criteria become correspondingly more stringent. The Discharger has not specifically collected hardness data for the receiving water. However, the Central Coast Water Board’s Central Coast Ambient Monitoring Program has nearby monitoring stations on San Luis Obispo Creek that has collected this information. The Water Board used 330 mg/L as CaCO3 as a conservative estimate of the receiving water hardness to determine hardness-based criteria. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-22 To conduct the RPA, the Central Coast Water Board identified the maximum observed effluent (MEC) and background (B) concentrations for each priority, toxic pollutant from receiving water and effluent data provided by the Discharger and compared this data to the most stringent applicable water quality criterion (C) for each pollutant from the NTR, CTR, and the 2019 Basin Plan. The Discharger did not collect background data (B) for receiving water. Section 1.3 of the SIP establishes three triggers for a finding of reasonable potential. 4.3.3.1. Trigger 1. If the MEC is greater than C, there is reasonable potential, and an effluent limitation is required. 4.3.3.2. Trigger 2. If B is greater than C, and the pollutant is detected in effluent (MEC > ND), there is reasonable potential, and an effluent limitation is required. 4.3.3.3. Trigger 3. After reviewing other available and relevant information, a permit writer may decide that a WQBEL is required. Such additional information may include, but is not limited to: the facility type, the discharge type, solids loading analyses, lack of dilution, history of compliance problems, potential toxic impact of the discharge, fish tissue residue data, water quality and beneficial uses of the receiving water, CWA 303(d) listing for the pollutant, and the presence of endangered or threatened species or their critical habitat. For mercury in particular, Part 2 of the SIP revised the above methodology as follows, pursuant to State Water Board Resolution 2017-0027, Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California-Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions (Mercury Provisions). 4.3.3.4. Most stringent water quality objective. The RPA is to use a water column concentration from SIP Part 2’s Table 1 based on the receiving water body type and beneficial use(s) to identify the most stringent mercury water quality objective. For San Luis Obispo Creek, the applicable water column concentration is 0.012 ug/L total mercury. This water column concentration is to be used as the “C” value in the RPA for mercury. This change in methodology changes the water quality objective from 0.05 ug/L in the previous orders to 0.012 ug/L in this Order. 4.3.3.5. Maximum Effluent Concentration. Instead of using the highest observed mercury effluent concentration, the MEC is to be determined as an arithmetic mean of all mercury samples during a calendar year. For this RPA, the highest calendar year arithmetic mean based on the revised methodology for mercury in effluent was 0.03 ug/L. The Discharger collects effluent mercury samples on a yearly basis. 4.3.3.6. Maximum ambient background concentration. Instead of using the highest observed mercury concentration in the upstream receiving water (referred to as “B”), the value of B is to be determined as an arithmetic mean of all mercury samples during a calendar year. This Discharger did not sample for and does not have ambient background concentration data for mercury. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-23 4.3.3.7. Determination. A mercury WQBEL is not required unless the MEC is greater than C. However, if B is greater than C and mercury is detected in the effluent, effluent monitoring is required. A mercury WQBEL is required for this discharge because the MEC (i.e., the highest calendar year average concentration with using one half the mercury detection limits when non -detect) was greater than C and there was no B data available. Therefore, according to Part 2 of the SIP, a mercury effluent limitation is required. Annual monitoring for mercury will be retained from the previous Order. The following table summarizes the RPA for each priority, title 22, or Basin Plan pollutant for which data was available from December 2014 through December 2022 and sets forth the basis upon which WQBELs are included in this Order. Table F-8. Summary of RPA Results CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Priority Pollutants 1 Antimony, Total Recoverable µg/L 9 2.5 6 - No Primary MCL 2 Arsenic, Total Recoverable µg/L 9 <2.0 10 - No Primary MCL 3 Beryllium µg/L 9 <0.2 4 - No Primary MCL 4 Cadmium, Total Recoverable µg/L 9 <0.2 3 - No CA Prim. MCL 5a Chromium (III) µg/L 7 7.0 50 - No CA Prim. MCL for Chromium (Total) 5b Chromium (VI) µg/L 8 1.1 11 - No CTR - Chronic 6 Copper, Total Recoverable µg/L 9 24 26 - No CTR - Chronic 7 Lead, Total Recoverable µg/L 8 6.3 15 - No CA Prim. MCL 8 Mercury, Total Recoverable µg/L 9 0.03 0.012 - Yes Mercury Provisions 9 Nickel, Total Recoverable µg/L 9 7.0 100 - No CA Prim. MCL 10 Selenium, Total Recoverable µg/L 9 1.0 5 - No CTR - Chronic CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-24 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 11 Silver, Total Recoverable µg/L 8 <0.25 31.6 - No CTR - Acute 12 Thallium, Total Recoverable µg/L 9 <0.2 1.7 - No CTR 13 Zinc, Total Recoverable µg/L 9 100 330 - No CTR 14 Cyanide, Total (as CN) µg/L 9 <4.0 5.2 - No CTR 15 Asbestos Million Fibers/L 9 <0.2 7 - No CTR 16 2,3,7,8 TCDD µg/L 9 <0.00000 0251 0.00000001 3 - Ud CTR 17 Acrolein µg/L 8 <5.0 320 - No CTR 18 Acrylonitrile µg/L 8 <2.0 0.059 - Ud CTR 19 Benzene µg/L 9 <0.5 1 - No CA Prim. MCL 20 Bromoform µg/L 73 1.1 4.3 - No CTR 21 Carbon Tetrachloride µg/L 9 <0.5 0.25 - Ud CTR 22 Chlorobenzene µg/L 9 <0.5 70 - No CA Prim. MCL 23 Chlorodibromomethane (aka Dibromochloromethane) µg/L 73 5.4 0.401 - Yes CTR 24 Chloroethane µg/L 8 <0.5 No Criteria - Uc No criteria 25 2-Chloroethylvinyl ether µg/L 8 <1.0 No Criteria - Uc No criteria 26 Chloroform µg/L 8 95.7 60 - Yes NAWQC 27 Dichlorobromomethane µg/L 73 24.8 0.56 - Yes CTR 28 1,1-Dichloroethane µg/L 9 <0.5 5 - No Primary MCL 29 1,2-Dichloroethane µg/L 9 <0.5 0.38 - Ud CTR 30 1,1-Dichloroethylene µg/L 9 <0.5 0.057 - No CTR 31 1,2-Dichloropropane µg/L 9 <0.5 0.52 - No CTR 32 1,3-Dichloropropylene µg/L 1 <0.5 0.5 - No CA Prim. MCL 33 Ethylbenzene µg/L 9 <0.5 300 - No CA Prim. MCL 34 Methyl Bromide (aka Bromomethane) µg/L 8 <0.5 48 - No CTR 35 Methyl Chloride (aka chloromethane) µg/L 8 <0.5 No Criteria - Uc No criteria 36 Methylene Chloride µg/L 9 15 4.7 - Yes CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-25 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 37 1,1,2,2-Tetrachloroethane µg/L 9 <0.5 0.17 - Ud CTR Tetrachloroethylene (aka Tetrachloroethene) µg/L 7 <0.5 0.8 - No CTR 39 Toluene µg/L 9 <0.5 150 - No CA Prim. MCL 40 1,2-Trans-Dichloroethylene µg/L 7 <0.005 10 - No CA Prim. MCL 41 1,1,1-Trichloroethane µg/L 9 <0.5 200 - No CA Prim. MCL 42 1,1,2-Trichloroethane µg/L 9 <0.5 0.6 - No CTR 43 Trichloroethylene (aka Trichloroethene) µg/L 7 <0.5 2.7 - No CTR 44 Vinyl Chloride µg/L 9 <0.5 0.5 - No CA Prim. MCL 45 2-Chlorophenol µg/L 8 <2.0 120 - No CTR 46 2,4-Dichlorophenol µg/L 8 <2.0 93 - No CTR 47 2,4-Dimethylphenol µg/L 8 <1.0 540 - No CTR 48 4,6-dinitro-o-resol (aka 2-methyl-4,6- Dinitrophenol aka 4,6-Dinitro-2- methylphenol) µg/L 7 <1.0 13.4 - No CTR 49 2,4-Dinitrophenol µg/L 8 <5.0 70 - No CTR 50 2-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 51 4-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 52 3-Methyl-4-Chlorophenol (aka P-chloro-m-resol aka 4-Chloro-3- methylphenol) µg/L 8 <1.0 No Criteria - Uc No criteria 53 Pentachlorophenol µg/L 34 2 0.28 - Yes CTR 54 Phenol, Single Compound µg/L 1 <1.0 1 - No BP 55 2,4,6-Trichlorophenol µg/L 8 <1.0 2.1 - No CTR 56 Acenaphthene µg/L 8 <1.0 1200 - No CTR 57 Acenaphthylene µg/L 8 <1.0 No Criteria - Uc No criteria 58 Anthracene µg/L 8 <1.0 9600 - No CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-26 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 59 Benzidine µg/L 8 <1.0 0.00012 - Ud CTR 60 Benzo(a)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 61 Benzo(a)Pyrene µg/L 9 <0.1 0.0044 - Ud CTR 62 Benzo(b)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 63 Benzo(ghi)Perylene µg/L 8 <1.0 No Criteria - Uc No criteria 64 Benzo(k)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 65 Bis(2- Chloroethoxy)Methane µg/L 8 <1.0 No Criteria - Uc No criteria 66 Bis(2-Chloroethyl)Ether µg/L 8 <1.0 0.031 - Ud CTR 67 Bis(2-Chloroisopropyl)Ether µg/L 8 <1.0 1400 - No CTR 68 Bis(2-Ethylhexyl) Phthalate (aka Di(2-ethylhexyl) Phthalate) µg/L 9 <2.0 1.8 - Ud CTR 69 4-Bromophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 70 Butylbenzyl Phthalate µg/L 8 <1.0 3000 - No CTR 71 2-Chloronaphthalene µg/L 8 <1.0 1700 - No CTR 72 4-Chlorophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 73 Chrysene µg/L 8 <1.0 0.0044 - Ud CTR 74 Dibenzo(a,h)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 75 1,2-Dichlorobenzene µg/L 10 <0.5 600 - No CA Prim. MCL 76 1,3-Dichlorobenzene µg/L 9 <0.5 400 - No CTR 77 1,4-Dichlorobenzene µg/L 10 <0.5 5 - No CA Prim. MCL 78 3,3 Dichlorobenzidine µg/L 8 <1.0 0.04 - Ud CTR 79 Diethyl Phthalate µg/L 8 <1.0 23000 - Ud CTR 80 Dimethyl Phthalate µg/L 8 <1.0 313000 - No CTR 81 Di-n-Butyl Phthalate µg/L 8 <1.0 2700 - No CTR 82 2,4-Dinitrotoluene µg/L 8 <1.0 0.11 - Ud CTR 83 2,6-Dinitrotoluene µg/L 8 <1.0 No Criteria - Uc No criteria 84 Di-n-Octyl Phthalate µg/L 8 <1.0 No Criteria - Uc No criteria CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-27 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 85 1,2-Diphenylhydrazine µg/L 8 <1.0 0.04 - Ud CTR 86 Fluoranthene µg/L 8 <1.0 300 - No CTR 87 Fluorene µg/L 8 <1.0 1300 - No CTR 88 Hexachlorobenzene µg/L 8 <1.0 0.00075 - Ud CTR 89 Hexachlorobutadiene µg/L 8 <1.0 0.44 - Ud CTR 90 Hexachlorocyclopentadiene µg/L 8 <1.0 50 - No CA Prim. MCL 91 Hexachloroethane µg/L 8 <1.0 1.9 - No CTR 92 Indeno(1,2,3-cd)Pyrene µg/L 8 <1.0 0.0044 - Ud CTR 93 Isophorone µg/L 8 <1.0 8.4 - No CTR 94 Naphthalene µg/L 8 <1.0 No Criteria - Uc No criteria 95 Nitrobenzene µg/L 8 <1.0 17 - No CTR 96 N-Nitrosodimethylamine µg/L 35 <0.001 0.00069 - No CTR 97 N-Nitrosodi-n-Propylamine µg/L 8 <1.0 0.005 - Ud CTR 98 N-Nitrosodiphenylamine µg/L 8 <1.0 5 - No CTR 99 Phenanthrene µg/L 8 <1.0 No Criteria - Uc No criteria 100 Pyrene µg/L 8 <1.0 960 - No CTR 101 1,2,4-Trichlorobenzene µg/L 9 <0.5 5 - No CA Prim. MCL 102 Aldrin µg/L 9 <0.005 0.00013 - Ud CTR 103 alpha-BHC µg/L 8 <0.005 0.0039 - Ud CTR 104 beta-BHC µg/L 8 <0.005 0.014 - No CTR 105 gamma-BHC µg/L 10 <0.005 0.019 - No CTR 106 delta-BHC µg/L 8 <0.005 No Criteria - Uc No criteria 107 Chlordane µg/L 9 <0.047 0.00057 - Ud CTR 108 4,4'-DDT µg/L 8 <0.005 0.00059 - Ud CTR 109 4,4'-DDE µg/L 8 <0.005 0.00059 - Ud CTR 110 4,4'-DDD µg/L 8 <0.005 0.00083 - Ud CTR 111 Dieldrin µg/L 9 <0.005 0.00014 - Ud CTR 112 alpha-Endosulfan µg/L 8 <0.005 0.056 - No CTR 113 beta-Endolsulfan µg/L 8 <0.005 0.056 - No CTR 114 Endosulfan Sulfate µg/L 8 <0.005 110 - No CTR 115 Endrin µg/L 10 <0.005 0.036 - No CTR CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-28 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 116 Endrin Aldehyde µg/L 7 <0.005 0.76 - No CTR 117 Heptachlor µg/L 10 <0.005 0.00021 - Ud CTR 118 Heptachlor Epoxide µg/L 10 <0.005 0.00011 - Ud CTR 119- 125 PCBs sum µg/L 2 <0.5 0.00017 - Ud CTR 126 Toxaphene µg/L 9 <0.24 0.0002 - Ud CTR Non-Priority Pollutants Drinking Water Quality Objectives Aluminum µg/L 9 150 200 - No CA Sec. MCL Barium µg/L 9 42.9 1000 - No CA Prim. MCL Fluoride mg/L 9 0.7 1 - No BP Nitrate, Total (as N) mg/L 151 51.7 10 8.1 Yes EPA Prim. MCL Nitrate + Nitrite (as N) mg/L 7 43.4 10 - Yes CA Prim. MCL Nitrite, Total (as N) mg/L 106 5.1 1 <0.1 Yes CA Prim. MCL Methyl-tert-butyl ether µg/L 9 <1.0 5 - No CA Sec. MCL Styrene µg/L 9 <0.5 100 - No CA Prim. MCL Alachlor µg/L 9 <0.1 2 - No CA Prim. MCL Atrazine µg/L 9 <0.1 1 - No CA Prim. MCL Bentazon µg/L 9 <2.0 18 - No CA Prim. MCL Carbofuran µg/L 9 <5.0 18 - No CA Prim. MCL 2,4-D µg/L 9 5 70 - No CA Prim. MCL Dalapon µg/L 9 <10.0 200 - No CA Prim. MCL Dibromochloropropane (aka 1,2-Dibromo-3- Chloropropane) µg/L 8 <0.01 0.2 - No CA Prim. MCL Di(2-ethylhexyl)adipate µg/L 9 <5.0 400 - No CA Prim. MCL Dinoseb µg/L 9 <1.0 7 - No CA Prim. MCL Diquat µg/L 9 <2.0 20 - No CA Prim. MCL Endothall µg/L 9 <40 100 - No CA Prim. MCL Ethylene Dibromide (aka 1,2-Dibromoethane) µg/L 8 <0.02 0.05 - No CA Prim. MCL CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-29 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Glyphosate µg/L 9 <20.0 700 - No CA Prim. MCL Methoxychlor µg/L 10 <0.1 30 - No CA Prim. MCL Molinate µg/L 9 <0.1 20 - No CA Prim. MCL Oxamyl µg/L 9 <5.0 50 - No CA Prim. MCL Picloram µg/L 9 <1.0 500 - No CA Prim. MCL Simazine µg/L 9 <0.1 4 - No CA Prim. MCL Thiobencarb µg/L 9 <0.1 70 - No CA Prim. MCL 2,4,5-TP (Silvex) µg/L 9 <1.0 50 - No CA Prim. MCL Trichlorofluoromethane µg/L 9 <0.5 150 - No CA Prim. MCL 1,1,2-Trichloro-1,2,2- Trifluoroethane µg/L 3 <0.5 1200 - No CA Prim. MCL Xylenes µg/L 9 <0.5 1750 - No CA Prim. MCL Methylene blue activated substances (MBAS) µg/L 8 800 200 - Yes BP Un-ionized Ammonia (as N) mg/L [5] [5] 0.025 - Yes[5] BP Board 3 Basin Plan Water Quality Objectives for Agricultural Water Use Boron, Total µg/L 7 260 750 - No BP Cobalt, Total µg/L 7 4.0 50 - No BP Iron, Total µg/L 8 520 5000 - No BP Lithium, Total µg/L 7 14 2500d - No BP Manganese, Total µg/L 8 42.8 200 - No BP Molybdenum, Total µg/L 7 17 10 - Yes BP Vanadium, Total µg/L 7 5 100 - No BP San Luis Obispo Creek Sub-Area Surface Water Quality Objectives Total Dissolved Solids mg/L 38 990 650 470- 750[6] Yes BP Chloride mg/L 39 209 100 31- 92[6] Yes BP Sulfate, Total, (as SO4) mg/L 6 142 100 - Yes BP Sodium mg/L 35 181 50 29- 72[6] Yes BP [1] Number of data points available for the RPA. [2] If there is a detected value, the highest reported value is summarized in the table. If there are no detected values, if available, the lowest MDL is summarized in the table. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-30 [3] RPA Results: = Yes, if MEC > WQO/WQC, or B > WQO/WQC and MEC is detected; = No, if MEC and B are < WQO/WQC or all effluent data are undetected; = (Uc) Undetermined, if no criteria have been promulgated; = (Ud) Undetermined, for lack of data. As described in section 1.3 in the SIP, if monitoring results show non-detect for all samples of a pollutant and if all reported detection limits of the pollutant in the effluent are greater than or equal to the C value, the RWQCB shall require additional monitoring for the pollutant in place of a water quality-based effluent limitation. For pollutants with a result of Ud, additional monitoring is established through this permit. [4] Basis of Most Stringent Criteria CTR - California Toxics Rule’ CA Prim. MCL - California Primary MCL CA Sec. MCL - California Secondary MCL EPA Prim. MCL - EPA Primary MCL EPA Sec. MCL - EPA Secondary MCL NAWQC - National Ambient Water Quality Criteria BP - Central Coast Regional Board 2019 Basin Plan SWRCB 2017-0027 - Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California—Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. [5] The reasonable potential for the effluent to exceed the 2019 Basin Plan water quality objective for San Luis Obispo Creek for un-ionized ammonia is based on 93 concurrent upstream (RSW-004) and downstream (RSW-005) monitoring data results from December 2014 through April 2020. [6] Range of measured values. The 2019 Basin Plan Water Quality Objective for this pollutant is an annual mean. 4.3.4. WQBEL Calculations As detailed in Table F-6, reasonable potential has been determined for mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, total nitrate (as N), nitrate + nitrite (as N), total nitrite (as N), un- ionized ammonia (as N), methylene blue activated substances (MBAS), total molybdenum, total dissolved solids (TDS), sulfate, sodium, and chloride. The following example demonstrates how WQBELs were established for this Order for chlorodibromomethane. Step 1: For each water quality criterion/objective, an effluent concentration allowance (ECA) is calculated from the following equation to account for dilution and background levels of each pollutant. ECA = C + D (C – B), when C > B, and ECA = C when C ≤ B, Where, C = the applicable water quality criterion (adjusted for receiving water hardness and expressed as total recoverable metal, if applicable). CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-31 D = the dilution credit (here D = 0, as the Central Coast Water Board has no information with which to justify credit for dilution). B = the background concentration As discussed above, for this Order, dilution was not allowed; therefore: ECA = C For chlorodibromomethane, the applicable water quality criteria are: ECAHuman Health = 0.401 μg/L Step 2: For each ECA based on an aquatic life criterion, the long -term average discharge condition (LTA) is determined by multiplying the ECA times a factor (multiplier), which adjusts the ECA to account for effluent variability. The multiplier varies depending on the coefficient of variation (CV) of the data set and whether it is an acute or chronic criterion/objective. Table 1 of the SIP provides pre-calculated values for the multipliers based on the value of the CV. When the data set contains less than 10 sample results, or 80 percent or more of the data are reported as non -detect (ND), the CV is set equal to 0.6. Derivation of the multipliers is presented in Section 1.4 of the SIP. LTAacute = ECAacute x Multiplieracute 99 LTAchronic= ECAchronic x Multiplierchronic 99 Typically, historic effluent data is used to develop the acute and chronic LTA using equations provided in Section 1.4, Step 3 of the SIP (Table 1 of the SIP also provides this data up to three decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the development of this permit and LTA for acute and chronic were unnecessary to calculate. Step 3: WQBELs, including an AMEL and a MDEL are calculated using the most limiting (the lowest) LTA. The LTA is multiplied times a factor that accounts for averaging periods and exceedance frequencies of the effluent limitations, and for the AMEL, the effluent monitoring frequency. Here, the sampling frequency is set equal to 1 (n = 1). The 99th percentile occurrence probability was used to determine the MDEL multiplier and a 95th percentile occurrence probability was used to determine the AMEL multiplier. Table 2 of the SIP presents the MDEL and AMEL multipliers as a function of the CV. When the data set contains less than 10 sample results, or when 80 percent or more of the data set is reported as non-detect (ND), the CV is set equal to 0.6. Otherwise, the CV is calculated as the standard deviation divided by the mean. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-32 No. of Samples No. of Samples Per Month (n) CV 73 1 0.6 Step 4: Calculate the WQBELs by multiplying the LTA by a factor (multiplier). WQBELs are expressed as AMEL and MDEL. The multiplier is a statistically based factor that adjusts the LTA for the averaging periods and exceedance frequencies of the criteria/objectives and the effluent limitations. The value of the multiplier varies depending on the probability basis, the coefficient of variation (CV) of the data set, the number of samples (for AMEL) and whether it is a monthly or daily limit. Table 2 of the SIP provides pre-calculated values for the multipliers based on the value of the CV and the number of samples. Equations to develop the multipliers in place of using values in the tables are provided in Section 1.4, Step 5 of the SIP and will not be repeated here. AMELaquatic life = LTA x AMELmultiplier 95 MDELaquatic life = LTA x MDELmultiplier 99 AMEL multipliers are based on a 95th percentile occurrence probability, and the MDEL multipliers are based on the 99th percentile occurrence probability. If the number of samples is less than four (4), the default number of samples to be used is four (4). Equations provided in Section 1.4, Step 5 of the SIP are used to develop the AMEL and MDEL for aquatic life using (Table 2 of the SIP also provides this data up to two decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the developmen t of this permit and AMEL and MDEL for aquatic life were unnecessary to calculate. Calculation of human health AMEL and MDEL: Step 5: For the ECA based on human health, set the AMEL equal to the ECAhuman health AMELhuman health = ECAhuman health For chlorodibromomethane: AMELhuman health = 0.401 μg/L Step 6: Calculate the MDEL for human health by multiplying the AMEL by the ratio of the MultiplierMDEL to the MultiplierAMEL. Table 2 of the SIP provides pre-calculated ratios to be used in this calculation based on the CV and the number of samples. MDELhuman health = AMELhuman health x (MultiplierMDEL / MultiplierAMEL) For chlorodibromomethane the following data were used to develop the MDELhuman health: No. of Samples Per Month CV MultiplierMDEL 99 MultiplierAMEL 95 Ratio CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-33 1 0.6 3.11 1.55 2.01 MDELhuman health = 0.401 μg/L x 2.01 = 0.806 μg/L Step 7: Select the lower of the AMEL and MDEL based on aquatic life and human health as the water-quality based effluent limit for the Order. For chlorodibromomethane, the AMELhuman health and MDELhuman health were 0.401 μg/L and 0.806 μg/L respectively. Thus, the human health criteria-based effluent limitations were more stringent and were considered in the Order. 4.3.4.1 Constituents with Reasonable Potential 4.3.4.1.1 Mercury. The RPA used effluent data from December 2014 through December 2022 and showed that there was a reasonable potential for the discharge to exceed the total recoverable mercury criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.012 µg/L and an MDEL of 0.024 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total recoverable mercury. 4.3.4.1.2 Chlorodibromomethane. The previous Order established an AMEL of 0.40 µg/L and an MDEL of 1.0 µg/L for chlorodibromomethane (dibromochloromethane). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chlorodibromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.4 µg/L and an MDEL of 0.81 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chlorodibromomethane. 4.3.4.1.3 Chloroform. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chloroform criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chloroform. 4.3.4.1.4 Dichlorobromomethane. The previous Order established an AMEL of 0.56 µg/L and an MDEL of 1.0 µg/L for dichlorobromomethane. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the dichlorobromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.56 µg/L and an MDEL of 0.96 µg/L have been established in this permit. Effluent and receiving water CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-34 monitoring and reporting requirements have also been established for dichlorobromomethane. 4.3.4.1.5. Methylene Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the methylene chloride criteria; therefore, effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 4.7 µg/L and an MDEL of 9.45 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for methylene chloride. 4.3.4.1.6. Pentachlorophenol. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the pentachlorophenol criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for pentachlorophenol. 4.3.4.1.8. Nitrate and Nitrate + Nitrite. As previously discussed, an effluent limitation for total nitrate (as N) was established through the TMDL for nitrate-nitrogen discharges to San Luis Obispo creek and was retained from the previous permit. Additionally, an effluent limitation for total nitrite (as nitrogen) is established in this order. A separate effluent limitation has not been established for nitrate+nitrite. Nitrate+nitrite is the sum of nitrate and nitrite, and therefore is duplicative of the two established effluent limitations. 4.3.4.1.9. Nitrite. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the total nitrite (as N) criteria, and therefore an effluent limitation is established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 1.0 mg/L has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total nitrite (as N). 4.3.4.1.10. Methylene blue activated substances (MBAS). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the MBAS criteria of 0.2 mg/L from the 2019 Basin Plan. The 0.2 mg/L effluent limitation established in this order is equivalent to the most stringent water quality objective in the 2019 Basin Plan . Effluent and receiving water monitoring and reporting requirements have also been established for MBAS. 4.3.4.1.11 Un-ionized Ammonia. The 2019 Basin Plan includes a water quality objective for un-ionized ammonia (NH3) of 0.025 mg/L. The previous Order did not establish an effluent limitation for un-ionized ammonia. The previous Order incorporated the Basin Plan objective as a receiving water limitation. From December 2014 through April 2020, the Discharger collected 93 concurrent upstream (RSW -004) and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-35 downstream (RSW-005) samples to determine un-ionized ammonia concentrations in the receiving water. The effluent caused the receiving water to exceed the Basin Plan objective on 29 occasions. Reasonable potential was found for un-ionized ammonia, and an effluent limitation and monitoring requirement were established for un -ionized ammonia. The effluent limitation of 0.025 mg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. 4.3.4.1.12. Molybdenum. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the molybdenum criteria of 10 µg/L from the 2019 Basin Plan. An effluent limitation of 10 µg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for molybdenum. 4.3.4.1.13. Total Dissolved Solids. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the total dissolved solids criteria of 650 mg/L in the Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for total dissolved solids. 4.3.4.1.14. Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the chloride criteria of 100 mg/L from the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek . Effluent and receiving water monitoring and reporting requirements have also been established for chloride. 4.3.4.1.15. Sulfate. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sulfate criteria of 100 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sulfate. 4.3.4.1.16. Sodium. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sodium criteria of 50 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sodium. 4.3.4.2 Constituents with No Reasonable Potential As detailed in Table F-8, constituents that were analyzed and received a “No” in the “RPA Result” column did not have a reasonable potential to cause or contribute to an excursion above the 126 U.S. EPA priority toxic pollutants, title 22 MCLs, or any CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-36 numeric water quality objectives included in any State Water Board plans or the 2019 Basin Plan. WQBEL’s are not included in this Order for constituents that do not demonstrate reasonable potential to cause or contribute to an instream excursion of an applicable water quality objective; however monitoring for priority toxic and title 22 pollutants is established in this Order. Most constituents with no reasonable potential are not discussed in this order. This section provides a discussion on the constituent with no reasonable potential for which an effluent limitation has not been retained from the previous order. 4.3.4.2.1 N-nitrosodimethylamine. The previous Order included an AMEL of 0.00069 µg/L and an MDEL of 0.0014 µg/L for n-nitrosodimethylamine. Several sample results analyzed during 2016 showed effluent limitation exceedances. However, in a letter dated February 9, 2017, the Discharger provided additional information to the Central Coast Water Board describing that the cause of the apparent exceedances was due to the test method used to analyze the samples. The Minimum Level (ML) established for n-nitrosodimethylamine in Appendix 4 of the SIP is 5 µg/L for samples analyzed by gas chromatography/ mass spectrometry. The Discharger was using EPA Method 1625M, an “ultra-low-level” method, which is not an approved method in 40 CFR part 136 and is not appropriate for compliance monitoring. The Discharger notified the Central Coast Water Board of its plan to return to using EPA Method 625 to measure n- nitrosodimethylamine in the effluent instead of the “ultra-low-level” the Discharger used in 2016 (i.e., EPA Method 1625M). On May 15, 2017, the Central Coast Water Board provided a written response that concurred with the Discharger regarding the return to EPA Method 625 and that the n-nitrosodimethylamine effluent concentrations reported in 2016 should not have been reported as effluent limitation exceedances because results below the ML of 5 µg/L are not considered violations according to the SIP. The RPA used effluent data from December 2014 through December 2022 that was analyzed using the correct test method and found that there was not reasonable potential for an exceedance of a water quality objective. An effluent limitation of n- nitrosodimethylamine has not been retained for this Order. Additional discussion is included in section 4.4.1 Ant-Backsliding Requirements and section 4.4.1 Antidegradation Policies of this fact sheet. 4.3.5. Whole Effluent Toxicity (WET) Aquatic toxicity is the adverse response of aquatic organisms from exposure to chemical or physical agents, or their synergistic effects in effluent or ambient water. Acute aquatic toxicity refers to adverse response (typically lethality) from a short -term exposure. Chronic aquatic toxicity generally refers to longer exposure duration and measures of both lethal and sub-lethal adverse response. WET testing protects receiving waters from the aggregate toxic effect of a mixture of pollutants that may be present in effluent. The Basin Plan establishes a narrative WQO which states that all waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-37 Survival of aquatic organisms in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge or for another control water. The WE T approach allows for protection of the narrative “no toxics in toxic amounts” criterion while implementing numeric criteria for toxicity. For compliance with the Basin Plan’s narrative toxicity objective and the 2022 Toxicity Provisions, this Order requires the Discharger to conduct WET testing for acute and chronic toxicity in accordance with the Test of Significant Toxicity (TST) statistical approach, as specified in section 5 of the MRP (Attachment E). 4.3.5.1. Test of Significant Toxicity (TST) In 2010, U.S. EPA endorsed the TST statistical hypothesis testing approach, described in the National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, as an improved hypothesis-testing tool to evaluate data from U.S EPA’s toxicity test methods. The TST hypothesis testing approach more reliably identifies toxicity —in relation to the chronic (0.25 or more) and acute (0.20 or more) mean responses of regulatory management concern—than the No Observed Effect Concentration (NOEC) hypothesis-testing approach previously used. On December 1, 2020, the State Water Board adopted Resolution No. 2020 -0044, establishing the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries (ISWEBE Plan), and adopting statewide numeric WQOs for both acute and chronic toxicity and a program of implementation to control toxicity, which are collectively known as the Toxicity Provisions. The Toxicity Provisions, which were revised on October 5, 2021, standardized the regulation of aquatic toxicity for all non- oceanic surface waters.3 U.S. EPA’s Test of Significant Toxicity Design, or TST, approach is an essential component of the Toxicity Provisions as it forms the basis for utilizing numeric WQOs and acts as the primary means of determining compliance with WET effluent limitations. This Order requires application of the TST approach for statistical analysis of WET data. 4.3.5.1.1. Test of Significant Toxicity Design The TST null hypothesis (Ho) for acute toxicity is: “mean discharge IWC response ≤0.80 × mean control response”, where 0.80 is the regulatory management decision (RMD). The TST null hypothesis (Ho) for chronic toxicity is: “mean discharge IWC response ≤0.75 × mean control response”, where 0.75 is the RMD. The null hypotheses for acute and chronic toxicity described in the TST are assigned as numeric WQOs for acute and chronic toxicity in sections II.C.1 and II.C.2 of the Toxicity Provisions. A test result t hat rejects the null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The TST approach is a t -test (formally Student’s t- 3 The Toxicity Provisions were approved by the Office of Administrative Law on April 25, 2022, and by U.S. EPA on May 1, 2023. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-38 test), a statistical analysis comparing two sets of replicate observations —in the case of WET tests, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”)). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month, or in consecutive calendar months, result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be re ported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). Compliance with the toxicity limitation is demonstrated by rejecting the null hypothesis and reporting “Pass”. When the toxicity test results in a “Fail” the Discharger must initiate accelerated monitoring as specified in section 5.3 of the MRP. After accelerated monitoring, if conditions of chronic toxicity are found to persist, the Discharger will be required to conduct a TRE, as described in section 5.4 of the MRP. See section III.B.3 of the Toxicity Provisions for a detailed step-by-step description of the TST statistical method. 4.3.5.2. WET Reasonable Potential Analysis To determine the need for acute and/or chronic toxicity effluent limitations, the Central Coast Water Board conducted a RPA using the TST approach. In conducting the RPA, the Central Coast Water Board considered and evaluated all acute and chronic toxicity data generated during the previous permit term since the data is representative of the actual effluent quality from the Facility. Reasonable potential exists if any of the acute or chronic toxicity tests result in a “Fail” or if the percent effect at the IWC is greater than 10 percent. The IWC for Discharge Point 001 is 100 percent effluent. The Discharger conducted eight acute and 26 chronic toxicity tests using the species Pimephales promelas between October 2015 and October 2022, as shown in Table F - 10 below. Analysis using the TST approach concluded that the Discharger failed zero acute toxicity tests, and 14 chronic toxicity tests, representing a fail rate of 54 percent. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-39 After extensive City staff and consultant review, summarized in the Toxicity Reduction Evaluation Workplan Conclusion report submitted to the Central Coast Regional Water Quality Control Board on May 22, 2019, all Effluent 001 sampling events from October 2016 to October 2018 exhibited at least one of the three qualifying data interpretations of sporadic mortality, suggesting biological interference was the cause of observed toxicity. The Central Coast Water Board reviewed the TRE Workplan and maintained that the failed chronic test results would remain on record. These chronic toxicity test results were used to conclude that the discharge has reasonable potential to cause or contribute to an exceedance of chronic toxicity WQOs and that the discharge is subject to chronic toxicity effluent limitations. In addition, section III.C.5.c. of the Toxicity Provisions requires establishment of chronic toxicity effluent limitations if a POTW is authorized to discharge at a rate equal to or greater than 5.0 MGD and is required to have a pretreatment program by the terms of 40 CFR section 403.8(a). The permitted flow rate for the Facility is 5.4 MGD, and the Discharger is required to have a pretreatment program. Therefore, based on the determination of the RPA, and requirements contained in the Toxicity Provisions, the Order establishes MDEL and MMEL effluent limitations for chronic toxicity. Table F-9. Summary of Acute and Chronic Toxicity Test Results Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 10/6/2015 Pass 2.50 Survival Acute 10/4/2016 Pass 0.00 Survival Acute 10/3/2017 Pass 10.00 Survival Acute 10/30/2018 Pass 0.00 Survival Acute 10/15/2019 Pass 7.50 Survival Acute 10/28/2020 Pass 0.00 Survival Acute 10/5/2021 Pass 0.00 Survival Acute 10/4/2022 Pass 0.00 Survival Acute 10/6/2015 Pass 8.68 Growth Chronic 10/6/2015 Pass 6.78 Survival Chronic 10/4/2016 Pass -13.56 Growth Chronic 10/4/2016 Pass 13.33 Survival Chronic 10/3/2017 Fail 31.69 Growth Chronic 10/3/2017 Fail 40.68 Survival Chronic 10/24/2017 Fail 49.63 Growth Chronic 10/24/2017 Fail 68.33 Survival Chronic 11/28/2017 Pass 17.20 Growth Chronic 11/28/2017 Pass 10.91 Survival Chronic 12/12/2017 Fail 43.78 Growth Chronic 12/12/2017 Fail 58.33 Survival Chronic 8/21/2018 Fail 19.95 Growth Chronic 8/21/2018 Fail 31.67 Survival Chronic 7/31/2018 Pass 14.48 Growth Chronic CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-40 Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 7/31/2018 Fail 34.48 Survival Chronic 10/30/2018 Pass 4.56 Growth Chronic 10/30/2018 Fail 18.33 Survival Chronic 10/15/2019 Pass -12.63 Growth Chronic 10/15/2019 Pass 1.75 Survival Chronic 10/28/2020 Pass -7.95 Growth Chronic 10/28/2020 Pass 0.00 Survival Chronic 10/5/2021 Pass -2.02 Growth Chronic 10/5/2021 Pass 0.00 Survival Chronic 10/4/2022 Pass 3.00 Growth Chronic 10/4/2022 Pass 0.00 Survival Chronic 4.3.5.3. Acute Aquatic Toxicity Although the Discharger reported no acute toxicity test failures from the eight acute toxicity tests conducted during the previous permit term, this permit retains annual effluent monitoring requirements for acute toxicity established in Order No. R3-2014- 0033 due to persistent failure of chronic toxicity tests during the previous permit term, which resulted in a required TRE being conducted. The Order implements federal guidelines (Regions 9 & 10 Guidance for Implementing Whole Effluent Toxicity Testing Programs) by requiring the Discharger to conduct acute species sensitivity testing as described in section 5 of the MRP (Attachment E). This Order requires the Discharger to conduct a screening test using a vertebrate and invertebrate species. After the screening test is completed, the Discharger is required to use the most sensitive species in future acute toxicity testing if the most sensitive species is found not to be Pimephales promelas. 4.3.6. Basin Plan and Bacteria Provisions 4.3.6.1. Bacteria Provisions. The Facility receives domestic wastewater and discharges to surface waters with the water contact recreation beneficial use (REC-1). Because of the nature of domestic wastewater, discharges from publicly owned treatment works with these discharge characteristics have the reasonable potential to cause or contribute to an exceedance of water quality criteria for bacteria. On August 7, 2018, the State Water Board adopted Part 3 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California – Bacteria Provisions and a Water Quality Standards Variance Policy (Bacteria Provisions), which establishes bacteria water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). Under the statewide Bacteria Provisions, the water quality objective protective of the REC-1 beneficial use is, in waters where the salinity is less than one part per thousand (ppth) 95 percent or more of the time: CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-41 • The concentration of E. coli shall not exceed 100 colony forming units (cfu) per 100 milliliters (mL) as a six-week rolling geometric mean, calculated weekly. • A statistical threshold value (STV) of 320 cfu/100 mL for E. coli shall not be exceeded by more than 10 percent of the samples collected in a calendar month and calculated in a static manner. Order R3-2014-0033 established effluent limitations for coliform bacteria based on applicable water quality objectives in the Basin Plan for San Luis Obispo Creek. The bacteria water quality objectives in the Bacteria Provisions supersede numeric water quality objectives for bacteria for the REC-1 beneficial use contained in a water quality control plan prior to February 4, 2019. Because San Luis Obispo Creek salinity is less than one part per thousand (ppth) 95 percent or more of the time , this Order establishes E. coli effluent limitations for Discharge Point 001, based on the water quality objectives in the Bacteria Provisions, in place of the previous fecal coliform effluent limitations. 4.3.6.2. Dissolved Oxygen. In order to protect the beneficial uses of San Luis Obispo Creek, Order R3-2014-0033 retained an effluent limit for dissolved oxygen, prohibiting the discharge from containing a dissolved oxygen concentration of less than 4.0 mg/L or so low that it adversely affects beneficial uses. 4.3.6.3. Nitrate. San Luis Obispo Creek is included on the 303(d) List as impaired for nutrients. Central Coast Water Board Resolution R3-2005-0106 established TMDLs for nitrate for discharges to San Luis Obispo Creek. Due to federal and State anti- backsliding regulations, nitrate remains a pollutant of concern for this discharge and the monthly average effluent limitation of 10 mg/L as N is retained from the previous Order. 4.3.6.4. pH. Federal regulations, 40 CFR 133, establish technology-based effluent limitations for pH. The secondary treatment standards require the pH of the effluent to be no lower than 6.0 and no greater than 9.0 standard units. However, the Basin Plan establishes a WQO for pH of between 6.5 to 8.3 standard units for the protection of receiving waters with the beneficial use of Municipal and Domestic Supply (MUN), Agricultural Supply (AGR), and Water Recreation (REC1 and REC2). The Basin Plan establishes a WQO for pH between 7.0 to 8.5 standard units for the beneficial use of Freshwater Habitat (COLD and WARM) and Fish Spawning (SPWN). The previous Order established an effluent limitation of 6.5 to 8.3. However, since San Luis Obispo Creek has MUN, AGR, REC1, REC2, COLD, WARM, and SPWN beneficial uses, a pH effluent limitation of 7.0 to 8.3 is appropriate in order to protect all beneficial uses. This Order updates the previous effluent limitation of 6.5 to 8.3 from the previous Order, based on the water quality objective for the Municipal and Domestic Supply (MUN) beneficial use. For the protection of the COLD beneficial use, this Order applies a receiving water limitation of 7.0 to 8.3, with no change in normal ambient pH levels above 0.5. 4.3.6.5. Oil and Grease. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works has the reasonable potential to cause or contribute to an exceedance of water quality criteria for oil and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-42 grease. The Basin Plan establishes a narrative effluent limitation for oil and grease, which states, “Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. The previous Order contained an AMEL and MDEL of 5.0 mg/L and 10 mg/L, respectively. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.3.6.6. Floating Material. Discharge of treated wastewater through Discharge Point No. 001 shall not contain floating material, including solids, liquids, foams, and scum in concentrations that cause nuisance or adversely affect beneficial uses. This effluent limitation is consistent with the Basin Plan. 4.3.6.7. Settleable Solids. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works have the reasonable potential to cause or contribute to an exceedance of water quality criteria for settleable solids. The Basin Plan establishes a narrative effluent limitation for settleable solids, which states, “Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely aff ects beneficial uses. The previous Order contained an average monthly effluent limitation (AMEL) of 0.1 mL/L. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.4. Final Effluent Limitation Considerations 4.4.1. Anti-Backsliding Requirements Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. 122.44(l) prohibit backsliding in NPDES permits. These anti-backsliding provisions require effluent limitations in a reissued permit to be as stringent as those in the previous permit, with some exceptions where limitations may be relaxed. All effluent limitations in this Order are at least as stringent as the effluent limitations in the previous Order. An effluent limitation for n-nitrosodimethylamine has not been retained from the previous Order because current data analysis shows no reasonable potential. The elimination of this WQBEL is consistent with the exception to the CWA's anti-backsliding requirements expressed at §402 (0)(2)(B)(i) of the Act, which allows a reissued permit to include less stringent limitations when information is available that was not available at the time of permit issuance (other than revised regulations, guidance, or test methods), and that would have justified the application of a less stringent effluent limitation at the time of permit issuance. The removal of the limitation of n- nitrosodimethylamine is based on new data, which was generated during the term of previous Order, and which demonstrates no reasonable potential for discharges from the Facility to cause or contribute to exceedances of applicable WQOs for this pollutant. Therefore, effluent limitations for these pollutants from the previous Order are not retained in this Order. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-43 4.4.2. Antidegradation Policies 40 CFR section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal antidegradation policy. On October 28, 1968, the State Water Board established California’s antidegradation policy when it adopted Resolution Number 68-16, Statement of Policy with Respect to Maintaining the Quality of the Waters of the State. Resolution Number 68-16 requires that existing water quality be maintained unless degradation is justified based on specific findings. The State Water Board has, in State Water Board Order Number 86-17 and an October 7, 1987 guidance memorandum, interpreted Resolution Number 68-16 to be fully consistent with the federal antidegradation policy contained in 40 CFR section 131.12. Similarly, CWA section 303(d)(4)(B) and 40 CFR section 131.12 require that all permitting actions be consistent with the federal antidegradation policy. Together, the state and federal antidegradation policies are designed to ensure that a water body will not be degraded resulting from the permitted discharge. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The renewal of this NPDES permit is consistent with the anti-degradation policy because it is not expected to allow degradation of receiving water quality. No reduction in the existing level of wastewater treatment is anticipated. In addition, the renewal of the NPDES permit will not lower the surface water quality because the conditions in this Order are at least as stringent as the previous permit except for limits described in section 4.4.1 of the Fact Sheet. Specifically, the removal of the final effluent limitation for n-nitrosodimethylamine is consistent with the antidegradation policy because the discharge did not exhibit reasonable potential to exceed the water quality objective, and it is not expected to degrade the water quality of the receiving water. Effluent and receiving water monitoring for this pollutant continue to be required under this Order to ensure effluent and receiving water concentrations do not exceed the objective. 4.4.3. Stringency of Requirements for Individual Pollutants This Order contains both technology-based and water quality-based effluent limitations for individual pollutants. The technology-based effluent limitations consist of restrictions on BOD and TSS. This Order’s technology-based pollutant restrictions implement the minimum applicable federal technology-based requirements. In addition, this Order contains effluent limitations more stringent than the minimum federal technology-based requirements that are necessary to meet water quality standards. For pH, BOD, and TSS both technology-based effluent limitations and water quality-based effluent limitations are applicable. The more stringent of these effluent limitations are implemented by this Order. These limitations are not more stringent than required by the CWA. Water quality-based effluent limitations have been derived to implement water quality objectives that protect beneficial uses. Both the beneficial uses and the water quality objectives have been approved pursuant to federal law and are the applicable federal water quality standards. To the extent that toxic pollutant water CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-44 quality-based effluent limitations were derived from the CTR, the CTR is the applicable standard pursuant to 40 C.F.R. 131.38. The procedures for calculating the individual water quality-based effluent limitations for priority pollutants are based on the CTR implemented by the SIP, which was approved by U.S. EPA on May 18, 2000. Any water quality objectives and beneficial uses submitted to U.S. EPA prior to May 30, 2000, but not approved by U.S. EPA before that date, are nonetheless “applicable water quality standards for purposes of the CWA” pursuant to 40 C.F.R. 131.21(c)(1). Collectively, this Order’s restrictions on individual pollutants are no more stringent than required to implement the requirements of the CWA. 4.4.4. Summary of Final Effluent Limitations 4.4.4.1. Effluent Limitations. The following effluent limitations are applicable to the discharge of disinfected tertiary treated wastewater from the Facility at Discharge Point No. 001. Table F-10. Final Effluent Limitations – Discharge Point EFF-001 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1,351 2,252 - - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - - TSS lbs/day[1] 425 1,351 3,378 - - - - pH[2],[3] standard units - - - 7.0 8.3 - - Oil and Grease mg/L 5 - 10 - - - - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-45 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - - Dissolved Oxygen mg/L - - - 4.0 - - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.01 2 - 0.024 - - - - Chlorodibromom ethane (Dibromochlorom ethane) µg/L 0.40 - 0.81 - - - - Chloroform µg/L 60 - 120.6 - - - - Dichlorobromom ethane µg/L 0.56 - 0.96 - - - - Methylene Chloride µg/L 4.7 - 9.45 - - - - Pentachlorophen ol µg/L 0.28 - 0.56 - - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - - Nitrite, Total mg/L 1 - - - - - - Un-ionized Ammonia mg/L 0.02 5 - - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - - Molybdenum mg/L 0.01 - - - - - - Total Dissolved Solids mg/L - - - - - 650[10] CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-46 [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 6.5-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 6.5-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0-9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 6.5-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Annual Average Chloride mg/L - - - - - 100[10] Sodium mg/L - - - - - 50[10] Sulfate mg/L -- - - - - 100[10] Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] - CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-47 with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30 - day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in -stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP -Attachment E). [10] Based on a 12-month running mean. 4.5. Interim Effluent Limitations – Not Applicable 4.6. Land Discharge Specifications – Not Applicable 4.7. Recycling Specifications This Order allows the production and onsite use of disinfected tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements in the State Water Board’s Recycled Water Policy, and those established by DDW at title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. This Order includes water reclamation requirements for the Facility pursuant to the State Water Board’s Division of Drinking Water recommendations submitted to the Central Coast Water Board. This Order requires the Discharger to adhere to the requirements outlined in section 4.3 and any additional conditions pursuant to specifications in updated title 22 engineering reports approved by the State Water Board’s Division of Drinking Water. 4.8. Point of Compliance for Effluent Limitations 4.8.1. The Discharger must comply with the effluent limitations established in this order at location EFF-001. The facility includes a long concrete pipe that sends treated effluent from the facility to San Luis Obispo Creek. In previous permits, the discharge was monitored at the end of the pipe, just before it mixes with San Luis Obispo Creek. Due to safety and cost concerns, the Discharger requested to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-48 perform the majority of their compliance monitoring at the beginning of the pipe. The beginning of the pipe is referred to as EFF-001A and the end of the pipe is referred to as EFF-001B. 5. RATIONALE FOR RECEIVING WATER LIMITATIONS 5.1. Surface Water Receiving water quality is a result of many factors, some unrelated to the discharge. This Order considers these factors and is designed to minimize the influence of the discharge on the receiving water. Specific water quality objectives established by the Basin Plan to meet this goal for all inland surface waters are included as receiving water limitations in section 5.1. of this Order. 6. RATIONALE FOR PROVISIONS 6.1. Standard Provisions Standard Provisions, which apply to all NPDES permits in accordance with 40 C.F.R. section 122.41, and additional conditions applicable to specified categories of permits in accordance with 40 C.F.R. section 122.42, are provided in Attachment D. The Discharger must comply with all standard provisions and with those additional conditions that are applicable under section 122.42. Sections 122.41(a)(1) and (b) through (n) of 40 C.F.R. establish conditions that apply to all state-issued NPDES permits. These conditions must be incorporated into the permits either expressly or by reference. If incorporated by reference, a specific citation to the regulations must be included in the Order. Section 123.25(a)(12) of 40 C.F.R. allows the state to omit or modify conditions to impose more stringent requirements. In accordance with 40 C.F.R. section 123.25, this Order omits federal conditions that address enforcement authority specified in 40 C.F.R. section 122.41(j)(5) and (k)(2) because the enforcement authority under the California Water Code is more stringent. In lieu of these conditions, this Order incorporates by reference California Water Code section 13387(e). 6.2. Special Provisions 6.2.1. Reopener Provisions The Order may be modified in accordance with the requirements set forth at 40 C.F.R. parts 122 and 124, to include appropriate conditions or limits based on newly available information, or to implement any, new state water quality objectives that are approved by the U.S. EPA. As effluent is further characterized through additional monitoring, and if a need for additional effluent limitations becomes apparent after additional effluent characterization, the Order will be reopened to incorporate such limitations. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential to cause, or contributes to an excursion above a SIP water quality objective. CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-49 6.2.2. Special Studies and Additional Monitoring Requirements 6.2.2.1. Whole Effluent Toxicity. The Basin Plan states, “All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board.” The Basin Plan further states, “Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality condition, shall not be less than that for the same waterbody in areas unaffected by the waste discharge…” and that effluent limitations based upon acute bioassays of effluent will be prescribed where appropriate. This permit establishes acute and chronic monitoring requirements, and chronic toxicity effluent limitations in accordance with the 2022 Toxicity Provisions, which incorporates the narrative objectives of the Basin Plan. The Order and MRP require the Discharger to conduct accelerated toxicity testing for exceedances of the acute toxicity WQOs, as described in the Toxicity Provisions, and/or chronic toxicity effluent limitations. If the accelerated testing demonstrates toxicity, the Discharger is required to submit a TRE Work Plan in accordance with U.S. EPA guidance, which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharge will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TIE process in accordance with the Work Plan if the results of toxicity testing exceed the effluent limitation or trigger for toxicity. 6.2.3. Best Management Practices and Pollution Prevention 6.2.3.1. Pollutant Minimization Program. The Discharger is required to minimize the discharge of pollutants consistent with the requirements of section 2.4.5.1 of the SIP. The goal of the Pollutant Minimization Program is to reduce all potential sources of a priority pollutant through pollutant minimization strategies to maintain the effluent concentration at or below water quality -based effluent limitations. 6.2.3.2. Salt and Nutrient Management Program. Section VI.C.3 of the previous Order required the Discharger to conduct a Salt Management Study to control levels of TDS, chloride, sodium, sulfate, and boron (collectively referred to as salts) in discharges from the Facility and attain applicable WQOs for salts in the San Luis Obispo Creek sub-basin of the Estero Bay Drainage Basin. Data from the term of the previous Order indicated the Facility has reasonable potential to cause or contribute to downstream impairment for salts loading. Therefore, in addition to effluent and receiving water monitoring for TDS, chloride, sulfate, boron and sodium, this Order requires the Discharger to continue to update and implement the Salt Management Program and provide CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-50 annual reports. Additionally, the Discharger shall develop and implement a Nutrient Management Program as part of the Salt and Nutrient Management Program, as discussed in section 6.3.3.1. of this Order, based on the Recycled Water Policy discussed in section 3.5.3. of this Fact Sheet. 6.2.4. Construction, Operation, and Maintenance Specifications 6.2.4.1 The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.2.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.2.5.1. Pretreatment. This Order contains pretreatment requirements consistent with applicable effluent limitations, national standards of performance, and toxic and performance effluent standards established pursuant to sections 208(b), 301, 302, 303(d), 304, 306, 307, 403, 404, 405, and 501 of the CWA, and amendments thereto. This permit contains requirements for the implementation of an effective pretreatment program pursuant to section 307 of the CWA; 40 CFR 35 and 403; and/or Title 23, CCR section 2233. 6.2.5.2. Collection System. The State Water Board issued General Waste Discharge Requirements for Sanitary Sewer Systems, Water Quality Order 2022-0103- DWQ (General Order) on December 6, 2022. The General Order requires public agencies that own or operate sanitary sewer systems with sewer lines one mile of pipe or greater to enroll for coverage and comply with the General Order. The General Order requires agencies to develop sanitary sewer management plans and report all sanitary sewer overflows, among othe r requirements and prohibitions. The General Order contains requirements for operation and maintenance of collection systems and for reporting and mitigating sanitary sewer overflows that are more extensive, and therefore, more stringent than the requirements under federal standard provisions. The Discharger obtained enrollment for regulation under the General Order 2022-0103-DWQ. 6.2.5.3. Resource Recovery from Anaerobically Digestible Material. Some POTWs choose to accept organic material such as food waste, fats, oils, and grease into their anaerobic digesters for co-digestion to increase production of methane and other biogases for energy production and to prevent such materials from being discharged into the collection system, which could cause sanitary sewer overflows. The California Department of Resources Recycling and Recovery has proposed an exemption from requiring Process Facility/Transfer Station permits where this activity is regulated under waste discharge requirements or NPDES permits. The proposed exemption is restricted to anaerobically digestible material that has been prescreened, slurried, and processed/conveyed in a closed system to be co-digested with regular POTW sludge. The proposed exemption requires that a POTW develop standard operating procedures for the proper handling, processing, tracking, and CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-51 management of the anaerobically digestible material before it is received by the POTW. Standard operating procedures are required for POTWs that accept hauled food waste, fats, oil, and grease for injection into anaerobic digesters. The development and implementation of standard operating procedures for management of these materials is intended to allow the California Department of Resources Recycling and Recovery to exempt this activity from separate and redundant permitting programs. If the POTW does not accept food waste, fats, oil, or grease for resource recovery purposes, it is not required to develop and implement standard operating procedures. 6.2.5.4. Biosolids. Provisions regarding sludge handling and disposal ensure that such activities will comply with all applicable regulations. 40 C.F.R. part 503 sets forth U.S. EPA’s final rule for the use and disposal of biosolids, or sewage sludge, and governs the final use or disposal of biosolids. The intent of this federal program is to ensure that sewage sludge is used or disposed of in a way that protects both human health and the environment. U.S. EPA’s regulations require that producers of sewage sludge meet certain reporting, handling, and disposal requirements. As the U.S. EPA has not delegated the authority to implement the sludge program to the State of California, the enforcement of sludge requirements that apply to the Discharger remains under U.S. EPA's jurisdiction at this time. U.S. EPA, not the Central Coast Water Board, will oversee compliance with 40 C.F.R. part 503. 6.2.5.5. Discharges of Stormwater. Discharges of stormwater from POTWs with a design capacity greater than 1.0 MGD are applicable for coverage under General State Water Board Order No. 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Dischargers of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.2.6. Other Special Provisions 6.2.6.1. Recycled Water Policy Salt/Nutrient Management Plan. This Order requires the Discharger to develop and implement a Salt/Nutrient Management Plan. This requirement is based on the Recycled Water Policy. 6.2.6.2. Climate Change Adaptation Program. On March 7, 2017, the State Water Board adopted a resolution in recognition of the challenges posed by climate change that requires a proactive approach to climate change in all State Water Board actions, including drinking water regulation, water quality protection, and financial assistance (Resolution 2017- 0012). The resolution lays the foundation for a response to climate change that is integrated into all State Water Board actions, by giving direction to the State Water Board divisions and encouraging coordination with the regional water quality control boards. This Order requires the Discharger to implement and submit a Climate Change Adaptation Program. The Central Coast Water Board is addressing the threats of climate change and flooding by including provisions CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-52 in new and reissued orders that ensure climate change mitigation and adaptation strategies are implemented. There is widespread scientific consensus that climate change is occurring and will continue at an accelerating rate into the future. Extreme weather events, including drought, high-intensity precipitation, flooding, and extreme heat have occurred through much of California in recent years and are projected to increase in frequency, extent, or intensity due to climate change. Climate change has the potential to impact discharging facilities through inundation, storm impacts, and erosion, increasing the risk of accidental discharge that results in discharge permit violations. These events have significant implications for wastewater treatment and operations, such as increased corrosion, deposition of solids, infiltration, overflows, inundation of facilities, impairment of treatment processes, and disruption of power or electrical components. Due to the long-term nature of these risks, there is a need to avoid piecemeal or reactionary adaptation and instead undertake proactive, long-term planning with consideration of various adaptation strategies that both keep facilities safe, maintain safe discharging practices, and avoid impacts to resources. A description of the actions taken by the Discharger are described in section 2.5 – Response to Climate Change of this Order. These requirements are consistent with 40 CFR section 122.41(e), requiring permittees to ensure compliance through proper operation and maintenance of facilities, including installation and operation of appropriate auxiliary and backup facilities, and they are authorized pursuant to Water Code section 13383. (In re the City of Oceanside, Fallbrook Public Utilities Dist. And the Southern California Alliance of Publicly Owned Treatment Works, State Water Board Order WQ 2021- 0005, February 12, 2021 at p. 26.) The Los Angeles Water Board understands that the cost of preparing such a plan could be significant (estimated cost range of $25,000-$60,000), but "the costs of ensuring resilient infrastructure to protect water quality against the effects of climate change is warranted." (Fallbrook, at p. 27.) 6.2.7. Compliance Schedules – Not Applicable 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS CWA section 308 and 40 C.F.R. sections 122.41(h), (j)-(l), 122.44(i), and 122.48 require that all NPDES permits specify monitoring and reporting requirements. Sections 13267 and 13383 of the California Water Code also authorize the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements related to discharges to navigable waters or publicly owned treatment works, with section 13267 being the specific statute authorizing all such activities pertaining to the State Water Board’s Water Quality Control Policy for Recycled Water. The MRP, Attachment E of this Order, establishes monitoring, reporting, and recordkeeping requirements that implement federal and state requirements. The following provides the rationale for the inclusion of the monitoring and reporting requirements contained in the MRP for this facility to CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-53 ensure compliance with Order requirements to ensure protection of water quality and beneficial uses. The Central Coast Water Board has considered the cost and need for monitoring and reporting generally in this NPDES permit. The discharger has provided the Central Coast Water Board with an estimation of its monitoring and reporting costs here, which are $226,860 for five years. Although the costs are significant, the costs are reasonable considering the nature of the wastewater discharge and because they result in critical data required under the Clean Water Act and which are needed to evaluate water quality generally, the impacts of the discharges on human and aquatic and benthic health, and water quality specifically, and to ensure that beneficial uses are protected. The requirements are generally comparable to other inland dischargers in the region. 7.1. Influent Monitoring In addition to influent flow monitoring, monitoring for BOD 5 and TSS is required to determine compliance with the Order’s percent removal requirement for these pollutants and to assess plant performance. Influent monitoring requirements have been retained from the previous Order. 7.2. Effluent Monitoring Effluent monitoring is necessary to determine compliance with effluent limitations and evaluate compliance with applicable water quality objectives and criteria. Effluent monitoring requirements have been retained from the previous Order for Discharge Point 001, with some exceptions. Effluent monitoring for fecal coliform has been removed and replaced with E. coli monitoring to be consistent with the updated Bacteria Provisions. Effluent monitoring frequency has been increased in this Order to monthly for those pollutants with a reasonable potential to cause or contribute to an exceedance of a water quality standards and for which effluent limitations were established: mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, nitrite (as N), un- ionized ammonia, MBAS, total dissolved solids, sulfate, chloride, and sodium. Chronic toxicity monitoring has increased to monthly to reflect the requirements of the updated Toxicity Provisions. A quarterly effluent monitoring requirement has been established for hardness to assist with the next permit’s reasonable potential analysis. An annual effluent monitoring frequency has been established for results of the reasonable potential analysis and the 2019 Basin Plan objectives . 7.3. Whole Effluent Toxicity Testing Requirements Acute and chronic toxicity monitoring requirements and chronic toxicity effluent limitations have been established in this Order in accordance with the 2020 Toxicity Provisions in the ISWEBE Plan. An acute toxicity test is conducted over a short time period and measures mortality. A chronic toxicity test is conducted over a longer period of time and may measure mortality, reproduction, and growth. For this permit, chronic toxicity in the discharge was evaluated using U.S. EPA’s 2010 TST hypothesis testing approach and is expressed as “Pass” or “Fail” for the median CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-54 monthly summary results and “Pass” or “Fail” and “Percent Effect” for each individual acute and chronic toxicity result. The chronic toxicity effluent limitations protect the narrative WQO in the Basin Plan and comply with the requirement in the Toxicity Provisions to establish chronic effluent limitations for Facilities with permitted discharges greater than 5.0 MGD and a pretreatment program. This Order requires the Discharger to submit an updated TRE Work Plan submitted pursuant to Order No. R3-2014-0033 within 90 days of the effective date of the Order. The TRE Work Plan must describe steps the Discharger intends to follow if the effluent limitation for chronic toxicity is exceeded. If a routine acute and/or chronic toxicity test results in a “Fail” at the IWC, this Order requires the Discharger to conduct accelerated monitoring to determine the cause of the toxicity. A TRE is required when the Discharger has any combination of two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. In addition, if other information indicates toxicity (e.g., results of additional monitoring, fish kills, intermittent recurring toxicity, etc.), then the Central Coast Water Board may require a TRE. If a TRE is required, the Discharger is required to submit a detailed TRE Work Plan in accordance with U.S. EPA guidance which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharger will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TRE/TlE process in accordance with the submitted work plan if the results of toxicity testing exceed the effluent limitations for chronic toxicity. This Order retains annual acute toxicity monitoring requirements and establishes monthly chronic toxicity monitoring requirements based on the RPA determination for toxicity using the TST approach and the Toxicity Provisions. Refer to section 5 of the MRP (Attachment E). 7.4. Recycled Water Monitoring Recycled water monitoring is necessary to evaluate compliance with recycling specifications detailed in section 4.3 of this Order. 7.5. Receiving Water Monitoring 7.5.1. Surface Water Surface water receiving water requirements are necessary to evaluate compliance with water quality objectives, WQBELs, and the protection of beneficial uses. Surface water monitoring requirements have been retained from Order R3-2014-0033 for Discharge Point 001, with some changes in sampling frequency and additional constituents to monitor. Annual monitoring for CTR and title 22 pollutants has been included in this Order because it had not been required historically and is necessary to obtain the background (B) concentration data that will be used for the next permit’s reasonable potential analysis. Quarterly sampling of E.coli has been included in this Order to be consistent with CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-55 the statewide Bacteria Provisions. Sampling frequency for flow, turbidity, color, pH, dissolved oxygen, and temperature have been decreased from weekly to monthly due to personnel safety concerns at sampling locations in the creek. Monthly monitoring of these parameters will provide sufficient data of the receiving water. Quarterly monitoring of boron and monthly monitoring of TDS, chloride, sodium, and sulfate have been included in this Order to provide an understanding of salts concentrations in the receiving water. The addition of quarterly monitoring of hardness in this Order will assist with the next permit’s reasonable potential analysis. 7.5.2. Groundwater Consistent with the previous permit, groundwater monitoring requirements have not been included. 7.6. Other Monitoring Requirements 7.6.1. Discharge Monitoring Report-Quality Assurance (DMR-QA) Study Program Under the authority of section 308 of the CWA (33 U.S.C. 1318), U.S. EPA requires major and selected minor dischargers under the NPDES Program to participate in the annual DMR-QA Study Program. The DMR-QA Study Program evaluates the analytical ability of laboratories that routinely perform or support self-monitoring analyses required by NPDES permits. There are two options to satisfy the requirements of the DMR-QA Study Program: (1) The Discharger can obtain and analyze a DMR-QA sample as part of the DMR-QA Study; or (2) Per the waiver issued by U.S. EPA to the State Water Board, the Discharger can submit the results of the most recent Water Pollution Performance Evaluation Study from its own laboratories or its contract laboratories. A Water Pollution Performance Evaluation Study is similar to the DMR-QA Study. Thus, it also evaluates a laboratory’s ability to analyze wastewater samples to produce quality data that ensure the integrity of the NPDES Program. The Discharger shall ensure that the results of the DMR-QA Study or the results of the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board. The State Water Board’s Quality Assurance Program Officer will send the DMR-QA Study results or the results of the most recent Water Pollution Performance Evaluation Study to U.S. EPA’s DMR-QA Coordinator and Quality Assurance Manager. 7.6.2. Annual Volumetric Reporting of Wastewater and Recycled Water To establish a realistic estimate of statewide recycled water use and potential for increased recycled water use statewide, the Recycled Water Policy requires Dischargers to report the volume of treated wastewater and recycled water. The annual report will meet implementation needs of the Recycled Water Policy and fill data gaps for additional statewide water planning efforts. The burden and cost of preparing the report is reasonable and consistent with the interest of the state in maintaining water quality and developing alternative water supplies to increase water resiliency. The Discharger shall ensure that all volumetric reporting requirements from this Order are submitted in electronic format via the State CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-56 Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. The State Water Board will evaluate progress towards the recycled water goals in the Recycled Water Policy and evaluate the need to update the recycled water goals in the future based on consistent statewide data. 7.6.3. Biosolids/Sludge Monitoring Biosolids monitoring shall be reported in the annual report in accordance with 40 C.F.R. 503. Biosolids monitoring requirements have been retained from the previous Order. 7.6.4. Pretreatment Monitoring Pretreatment monitoring shall be reported in the annual report in accordance with requirements in 40 C.F.R. 403.8. Pretreatment monitoring requirements have been retained from the previous Order. 7.6.5. Salt and Nutrient Management Plan Reporting Salt and Nutrient Management Plan reporting requirements have been retained in this Order to help identify and reduce salt and nutrient loading in effluent. This salt/nutrient management report shall be included as a separate report from the annual report. 7.6.6. Discharge to Evaporation Ponds Reports of discharge to and from the Facility’s evaporation ponds are required pursuant to California Water Code section 13383. Any costs incurred with this reporting are expected to be minimal. The reporting is necessary to ensure compliance with the provisions of this Order, inform follow-up actions in the event of noncompliance with the provisions of this Order, and to protect human health and water quality. 8. CONSIDERATION OF NEED TO PREVENT NUISANCE AND WATER CODE SECTION 13241 FACTORS The requirements set forth in subsections 2.4 and 4.3 of this Order are included to implement state law only. These requirements are not required or authorized under the federal CWA; consequently, violations of these requirements are not subject to the enforcement remedies that are available for NPDES violations. As required by Water Code section 13263, the Central Coast Water Board has considered the need to prevent nuisance and the factors listed in Water Code section 13241 in establishing the state law provisions/requirements. The Central Coast Water Board finds, on balance, that the state law requirements in this Order are reasonably necessary to prevent nuisance and to protect beneficial uses identified in the Basin Plan, and the section 13241 factors are not sufficient to justify failing to protect those beneficial uses. 8.1. Need to prevent pollution or nuisance In establishing effluent limitations in this Order, the Central Coast Water Board has considered state law requirements to prevent pollution or nuisance as defined in CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-57 section 13050, subdivisions (l) and (m), of the Water Code. The requirements in this Order, including those set forth in subsections 2.4 and 4.3, will prevent pollution and nuisance. 8.2. Past, present, and probable future beneficial uses of water Chapter 2 of the Basin Plan identifies designated beneficial uses for water bodies in the Central Coast Region. Beneficial uses of water relevant to this Order are also identified above in sections 3.3.1 of this Fact Sheet. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order, including those set forth in sections 2.4 and 4.3 of this Order. Accordingly, the requirements herein protect and augment the past, present and probable future beneficial uses of the water. 8.3. Environmental characteristics of the hydrographic unit under consideration, including the quality of water available thereto The environmental characteristics of this watershed are discussed in the Basin Plan, as well as available in State of the Watershed reports and the State’s CWA Section 303(d) List of impaired waters. The environmental characteristics of the hydrographic unit, including the quality of available recycled water that may be produced as a result of this Order will be improved by compliance with the requirements of this Order. 8.4. Water quality conditions that could reasonably be achieved through the coordinated control of all factors which affect water quality in the area The water quality standards necessary to protect beneficial uses of San Luis Obispo Creek Sub-Basin of the Estero Bay Drainage Basin can reasonably be achieved through the coordinated control of all factors that affect water quality in the area, including the conservation of water and/or the production of recycled water authorized by this Order. For example, the water quality in the watershed and/or groundwater basin could be improved through the addition or use of recycled water authorized by this Order, which meets title 22 standards. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order. 8.5 Economic Considerations The Permittee presented evidence regarding cost of monitoring but did not present additional evidence concerning other economic considerations related to this Order, such as the benefits of producing recycled water and benefits resulting from protection of beneficial uses of San Luis Obispo Creek. The Central Coast Water Board has considered the economic impact of requiring certain provisions pursuant to state law, including the costs of conducting feasibility studies for recycling, conservation, and climate change. Any additional costs associated with producing any study are reasonably necessary to prevent nuisance and protect beneficial uses identified in the Basin Plan and to improve the water supply resiliency. The failure to consider conservation or recycled water could result in the loss of, or impacts to, beneficial uses, which would have a detrimental economic impact, particularly given the effects on beneficial uses and supplies of water from the CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-58 drought and climate change. Economic considerations related to costs of compliance are therefore not sufficient, in the Central Coast Water Board’s determination, to justify failing to prevent nuisance and protect beneficial uses. 8.6 The need for developing housing within the region The Central Coast Water Board does not anticipate that these state law requirements will adversely impact the need for housing in the area. To the contrary, this Order helps address the need for housing by controlling pollutants in discharges and by allowing the reuse and exportation of recycled water for use in the area. Both of these things will improve the quality of local surface and groundwater, as well as water supply generally. This may in turn increase the region’s capacity to support continued housing development. Therefore, the potential for developing housing in the area will be facilitated by the conservation of water, or reuse or the production of recycled water, under this permit. 8.7. Need to develop and use recycled water The State Water Board’s Recycled Water Policy requires the Central Coast Water Board to encourage the use of recycled water. In addition, as discussed immediately above, a need to develop and use recycled water exists within the region, especially during times of drought. To encourage recycling, the Permittee is required by this Order to continue to explore the feasibility of recycling to maximize the beneficial reuse of tertiary treated effluent and to report on its recycled water production and use. The Discharger shall submit an update to this feasibility investigation as part of the submittal of the Report of Waste Discharge (ROWD) for the next permit renewal. 9. PUBLIC PARTICIPATION The Central Coast Water Board is considering the issuance of WDRs that will serve as an NPDES permit for the City of San Luis Obispo Water Resource Recovery Facility. As a step in the WDR adoption process, Central Coast Water Board staff developed tentative WDRs and encourages public participation in the WDR adoption process. 9.1. Notification of Interested Persons The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provid ed an opportunity to submit written comments and recommendations. Notification was provided via the Central Coast Water Board’s website and e-mail subscription service. The public can access the agenda and any changes in dates and locations through the Central Coast Water Board’s website at http://www.waterboards.ca.gov/centralcoast/ CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-59 9.2. Written Comments Interested persons were invited to submit written comments on December 14, 2023, concerning these tentative WDRs. To be fully responded to by staff and considered by the Central Coast Water Board, the written comments were due at the Central Coast Water Board office by 5:00 p.m. on January 16, 2024. 9.3. Public Hearing The Central Coast Water Board held a public hearing on the tentative WDRs during its regular Board meeting on the following date and time and at the following location: Date: June 20-21, 2024 Time: 9:00 am-5:00 pm Location: Link to video and teleconference were provided at https://www.waterboards.ca.gov/centralcoast/board_info/age ndas/2024/2024_agendas.html Interested persons were invited to attend. At the public hearing, the Central Coast Water Board heard testimony pertinent to the discharge, WDRs, and permit. For accuracy of the record, important testimony was requested in writing. 9.4. Reconsideration of Waste Discharge Requirements Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Board must receive the petition by 5:00 p.m., within 30 calendar days of the date of adoption of this Order at the following address, except that if the thirtieth day following the date of this Order falls on a Saturday, Sunday, or state holiday, the petition must be received by the State Water Board by 5:00 p.m. on the next business day: State Water Resources Control Board Office of Chief Counsel P.O. Box 100, 1001 I Street Sacramento, CA 95812-0100 Or by email at waterqualitypetitions@waterboards.ca.gov For instructions on how to file a petition for review, see the State Water Board’s website on instructions for filing water quality petitions at: https://www.waterboards.ca.gov/public_notices/petitions/water_quality/wqpetition_i nstr.shtml. 9.5. Information and Copying The Report of Waste Discharge, other supporting documents, and comments received are on file and may be inspected at the address above at any time CITY OF SAN LUIS OBISPO ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-60 between 8:00 a.m. and 5:00 p.m., Monday through Friday. Copying of documents may be arranged through the Central Coast Water Board by calling (805) 549- 3147. 9.6. Register of Interested Persons Any person interested in being placed on the mailing list for information regarding the WDRs and NPDES permit should contact the Central Coast Water Board, reference this facility, and provide a name, address, and phone number. 9.7. Additional Information Requests for additional information or questions regarding this order should be directed to Sarah Crable at (805) 549-3706 or Sarah.Crable@waterboards.ca.gov or Arwen Wyatt-Mair at (805) 542-4695 or Arwen.Wyattmair@waterboards.ca.gov. 46 From:Regulatory <regulatory-bounces@lists.casaweb.org> on behalf of Maile Lono-Batura via Regulatory <regulatory@lists.casaweb.org> Sent:Tuesday, July 1, 2025 4:11 PM To:Maile Lono-Batura via Regulatory Cc:Maile Lono-Batura Subject:[Regulatory] Waterkeepers Report Points to WW & Biosolids Attachments:July 2025 Waterkeeper Alliance PFAS Phase II Report_FINAL_6.26.25.pdf; ATT00001.txt Hello everyone, Please find the aƩached reports and news link below. A recent report from the Waterkeepers Alliance surveyed waterways and PFAS spikes downstream from WWTPs and biosolids applicaƟon fields. While menƟon is made of common household products containing PFAS and careful selecƟon of specific sampling sites to avoid other PFAS sources, the focus of the st udy was on WWTPs and biosolids spikes downstream of their ouƞall or applicaƟon. “Currently, there is liƩle accountability for PFAS entering our environment and water through poorly regulated pathways. American communiƟes are exposed daily, oŌen unknowingly, and many face serious, disproporƟonate health risks. The tools to address this crisis exist, but the poliƟcal will is lacking. We cannot afford more watered-down regulaƟons and loopholes for industrial source polluters. The science is clear: EPA and lawmakers must act decisively, and with urgency, in the public’s interest.” – Mark Yaggi, CEO of Waterkeeper Alliance hƩps://www.chemicalprocessing.com/environmental-protecƟon/water-wastewater/news/55300475/passive-samplers- deployed-in-19-states-detected-pfas-at-nearly-all-tested-sites-with-significant-increases-downstream Please share with others that may be interested. Thank you. Maile Lono-Batura, BCES, MNPL Director of Renewable Resources CA Association of Sanitation Agencies 925 L Street, Suite 200, Sacramento, CA 95814 916.446.0388 (office) | 916.432.3551 (mobile) casaweb.org | @casa_cleanwater | casacleanwater Disclaimer 47 The information contained in this communication from the sender is confidential. It is intended solely for use by the recipient and others authorized to receive it. If you are not the recipient, you are hereby notified that any disclosure, copying, distribution or taking action in relation of the contents of this information is strictly prohibited and may be unlawful. This email has been scanned for viruses and malware, and may have been automatically archived by Mimecast, a leader in email security and cyber resilience. Mimecast integrates email defenses with brand protection, security awareness training, web security, compliance and other essential capabilities. Mimecast helps protect large and small organizations from malicious activity, human error and technology failure; and to lead the movement toward building a more resilient world. To find out more, visit our website. file:///C/...bispo/Documents/PRR26230%20Jorgensen%20-%20WRRF%20Biosolids/Emails/1001-End%20Folder/Attachments/ATT00001.txt[8/25/2026 2:00:23 PM] _______________________________________________ Regulatory mailing list Regulatory@lists.casaweb.org http://lists.casaweb.org/mailman/listinfo/regulatory_lists.casaweb.org PFAS Report Phase II UNCOVERING PFAS CONTAMINATION IN FRONTLINE COMMUNITIES 1 UNNATURALUNBREAKABLEUNSEEN 1 TABLE OF CONTENTS Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 Current Policy Landscape . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 Key Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 Analysis and Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 Method Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22 Overview of Results for WWTP and Biosolids Sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24 PFAS Surface Water Contamination from WWTPs and Biosolids Land Application Fields . . . . . . .24 Wastewater Treatment Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26 Biosolids Land Application Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28 Specific PFAS Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29 Total PFAS Concentrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 PFAS Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38 Evaluation of Facilities and Watersheds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 Watersheds with the Greatest Downstream Total PFAS Concentration Increases . . . . . . . . .52 Black-Sampit Riverkeeper, Pocotaligo River, South Carolina . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52 Haw Riverkeeper, Haw River and Haw Creek, North Carolina . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55 Detroit Riverkeeper, Rouge River, Michigan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59 Potomac Riverkeeper, Monocacy River, Maryland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62 Tualatin Riverkeepers, Tualatin River, Oregon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 Inland Empire Waterkeeper, Santa Ana River, California . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69 Milwaukee Riverkeeper, Root River and Spring Creek, Wisconsin . . . . . . . . . . . . . . . . . . . . . . . . . . .72 Spokane Riverkeeper, Spokane River and Dragoon Creek, Washington . . . . . . . . . . . . . . . . . . . . . .75 Cape Fear Riverkeeper, Cape Fear and South Rivers, North Carolina . . . . . . . . . . . . . . . . . . . . . . . .78 Cahaba Riverkeeper and Black Warrior Riverkeeper, Cahaba River and Cane Creek, Alabama . .81 Sampling Results by Waterkeeper Group Watershed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84 Bayou City Waterkeeper, Hunting Bayou, Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84 Chattahoochee Riverkeeper, Chattahoochee River, Georgia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85 Coosa Riverkeeper, Big Wills Creek and Whippoorwill Creek, Alabama . . . . . . . . . . . . . . . . . . . . . .86 Hackensack Riverkeeper, Ramapo River, New York/New Jersey . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88 James Riverkeeper, Appomattox River and Old Town Creek, Virginia . . . . . . . . . . . . . . . . . . . . . . . .89 Long Island Soundkeeper, Naugatuck River, Connecticut . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91 Los Angeles Waterkeeper, Los Angeles River, California . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92 Narragansett Bay Riverkeeper, Pawtuxet River, Rhode Island . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93 Pearl Riverkeeper, Pearl River, Mississippi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94 Tampa Bay Waterkeeper, East Canal, Florida . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96 Upper Potomac Riverkeeper, Opequon Creek and Back Creek, West Virginia . . . . . . . . . . . . . . . .97 West Virginia Headwaters Waterkeeper, Ohio River, West Virginia . . . . . . . . . . . . . . . . . . . . . . . . . . .99 Policy Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106 ACKOWLEDGMENTS This report was produced by Waterkeeper® Alliance, New York, N .Y ., in cooperation with Hispanic Access Foundation, Washington, D .C ., and participating Waterkeeper groups from across the United States . Data and technical findings were supplied for the sole purpose of this report by the contracted service provider, SiREM Lab, Guelph, Ontario and Eurofins Environmental Testing USA, Sacramento, Calif . The SiREM Lab report containing all sample results can be accessed at waterkeeper .org/pfas . Analysis for the report was provided by Dr . Elizabeth Southerland, Ph .D ., former Director of the U .S . Environmental Protection Agency (EPA) Office of Science and Technology in the Office of Water and Robert W . Bowcock, Founder and Managing Director of Integrated Resource Management . A third-party scientific review was provided by Dominique Lueckenhoff, Executive Vice-President, at Hugo Neu Corporation and a former water program official with EPA and Laura Orlando, Senior Scientist at Just Zero . The monitoring project that led to the creation of this report was designed and implemented by Kelly Hunter Foster, Senior Attorney for Waterkeeper Alliance and Christian Breen, Waterkeeper Membership Services Manager for Waterkeeper Alliance . Kelly Hunter Foster and Katie Horner, Legal Fellow for Waterkeeper Alliance, also contributed watershed, facility, and data evalua- tions for the report . Kate Mulligan and Veronica Navarro from Michigan Law School provided copyedit and feedback support . ABOUT WATERKEEPER ALLIANCE Waterkeeper Alliance is a global movement uniting more than 300 community-based Waterkeeper groups around the world, focusing citizen action on issues that affect our waterways, from pollution to climate change . The Waterkeeper movement patrols and protects nearly six million square miles of rivers, lakes, and coastlines in the Americas, Europe, Australia, Asia, and Africa . DISCLAIMER Waterkeeper Alliance is responsible for the opinions and recommendations expressed or implied in this report and for obtaining permission from organization(s) that own the copyright to previously published material referenced herein . The contracted service provider is responsible for the authenticity of their materials, methodologies, data, and analysis referenced herein . FUNDERS Broad Reach Foundation Liquid I .V . Roaring Brook Family Foundation Roy A . Hunt Foundation SweetWater Brewing Company CREDITS Report design by Jon Harrison . Appendices, Figures, and Tables created by Waterkeeper Alliance . COPYRIGHT Waterkeeper Alliance grants permission to reproduce material in this publication for research, media, and not-for-profit purposes . Permission is given with the understanding that none of the material will be used to imply endorsement of a particular product, method, or practice . It is expected that those reproducing the material in this document for research, media, and not-for-profit uses will give appropriate source acknowledgment . For other uses, submit a written permission request to media@waterkeeper .org . 180 Maiden Lane, Suite 603, New York, N .Y . 10038 © 2025 Waterkeeper Alliance 3 This report presents novel, targeted data from a mon- itoring project focused on locations near wastewater treatment plants (WWTPs) and permitted biosolids land application sites—suspected contributing sources of per- and polyfluoroalkyl substances (PFAS) to waterway contamination . The findings confirm that PFAS contami- nation is both widespread and persistent, reinforcing the urgent need for stronger regulations, expanded research, increased funding, and improved treatment technolo- gies . This work adds timely, critical insight to the growing understanding of PFAS pollution, especially in frontline communities already facing disproportionate environmen- tal and health burdens . PFAS are a class of manufactured organic chemicals pervasive in the environment and linked to harmful public health and ecosystem impacts . Often referred to as “for- ever chemicals” because they do not break down or do so very slowly,1 PFAS have been widely used in various indus- trial and consumer products since at least the 1950s . As a class of chemicals, there are approximately 15,000 different derivatives2 that share similar molecular structures, environ- mental characteristics, and biological hazards . These toxic compounds are biopersistent, bioaccumulative, and pose serious health risks, including cancer, reproductive and developmental effects, immune system dysfunction, and hormonal disruption .3 Largely unregulated by EPA and many state agencies, PFAS are widely released from sources such as industrial wastewater, landfill leachate, and effluent, sewage sludge, and biosolids from wastewater treatment processes . As a result, PFAS have contaminated the environment, including both groundwater and surface water used for drinking .4 When sewage sludge is treated to meet EPA regulatory standards and is intended to be land applied as a soil conditioner or fertilizer on agricultural, forested, and other lands, the agency typically refers to it as biosol- ids (Class A or B) . Untreated or partially treated sewage sludge may be incinerated or disposed of in landfills—in dedicated monofills or co-disposed with municipal solid waste sites .5 Biosolids often contain PFAS but the federal regulatory standards and treatment process are not suffi- cient to control these pollutants . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 5 EXECUTIVE SUMMARY The pervasiveness of this contamination intensifies the potential harm to the environment and human health when facilities do not adequately contain, treat, and dispose of PFAS-contaminated wastewater and sewage sludge . These facilities6 can receive PFAS in wastewater from residential, commercial, and industrial sources that produce, manufacture, or use products that contain PFAS .7 As centralized collectors, WWTPs face significant chal- lenges due to underfunding and the limitations of tradi- tional treatment technologies . These technologies are not designed to remove or destroy compounds characterized by strong carbon-fluorine bonds and resistance to degra- dation . As a result, these substances are discharged into receiving surface waters through effluent or transferred through contaminated sewage sludge and biosolids . While PFAS are found in waterways across the country, their impacts are not equally distributed . Communities of color, low-income, and rural areas, which are often closer to sources of industrial pollution and have limited resources for water testing and treatment, face higher exposure risks and greater health vulnerabilities . Despite decades of releasing PFAS into the environ- ment, “few industrial facilities have PFAS monitoring requirements, effluent limitations,8 or pretreatment stan- dards9 for wastewater discharges” because EPA has not adopted national requirements .10 Because industrial wastewater is not adequately reg- ulated for PFAS, these chemicals often end up in sewage sludge, which is then processed into biosolids used on land . In 2022, EPA estimated that 56% of biosolids were land-applied for agriculture, reclamation, or other uses .11 By 2023, that figure had risen to 60%, with 31% applied to U .S . agricultural land—an 11% increase from the previous year .12 As a result, PFAS that are often present in biosol- ids have contaminated, and continue to contaminate, lands, livestock, waterways, and agricultural products across the country .13 The extent of PFAS contamination in U .S . surface waters was exposed in Waterkeeper Alliance’s 2022 Phase I monitoring project, in which 113 Waterkeeper groups collected a total of 228 PFAS samples in waterways from 34 states and the District of Columbia (D .C .) .14 The results were striking: PFAS were present in 83% of the water- ways tested, with at least one compound found in 95 out of 114 sites sampled . Of the 55 compounds analyzed, 35 were detected in 63 .6% of the sites . Overall, mea- surable concentrations were found in waterways across 29 states and D .C ., often at levels far exceeding EPA drink- ing water health advisory limits .15 Waterkeeper Alliance developed this Phase II water quality monitoring project to test surface waters for the presence of PFAS upstream and downstream from 22 WWTP sites and 10 biosolids land application fields in partnership with Hispanic Access Foundation and Waterkeeper groups in 19 states .16 This project utilized cutting-edge SiREM PFASsive™ sampling techniques and state-of-the-art analytical methods at Eurofins Environment Testing Calscience laboratory in Sacramento, Calif . (EPA Method 163317) . The monitoring evaluated and quan- tified PFAS contamination from municipal wastewater and biosolids land application fields over time, with a focus on disproportionately impacted communities . To our knowledge, this is the first monitoring project that employed passive sampling devices at WWTP-associated sites in multiple states, producing more representative data on PFAS equilibrium concentrations .18 By quantify- ing only dissolved PFAS contaminants, it provides a more accurate basis for bioavailability, toxicity, and risk assess- ment than conventional grab samples, which reflect total concentrations at a single timepoint . The resulting data enhances our understanding of PFAS migration path- ways, bioavailability, and impacts in U .S . surface waters . It further demonstrates that treatment processes and land application methods play a critical role in the release of these contaminants into surface waters, highlighting both limitations in current practices and areas where contami- nation is occurring .19 This evaluation also helped identify sites across the country where stronger measures are needed to control source pollution from industrial dischargers as well as subsequent passthrough discharges from WWTPs and bio- solids land application fields . Our evaluation of the PFAS sampling results also makes clear that existing laws, regulations, and conventional wastewater treatment technologies are not adequately controlling, preventing, or remediating PFAS pollution in surface waters, exposing people and ecosystems to seri- ous health risks . PFAS are synthetic chemicals that have contaminated nearly every part of the environment and many aspects of daily life . These compounds were deliberately engineered to resist heat, water, and oil, making them extremely difficult to break down under natural conditions . As a result, they persist in the environment, bioaccumulate in humans and wildlife, and cycle through air, water, soil, and living organisms, threatening public health and ecosystems . Their widespread use and remarkable persistence have led to global contamination and an urgent need for regulatory action and cleanup . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 76 EXECUTIVE SUMMARY INDUSTRY & M A NUFA C T URI NGAGRICULT U R E & LA N D USECOMMER C I A L STRU C T URESRESIDEN T IA L STRU C T U RESWASTEW A T E R TREA T MENTPHAR M A C EUTIC A L S SOLID W A S T E & LA N D F I LLSHUM A N S & ANIM A L S A T M O S PHERE WILDFLIF E & LIVES T OCKLAKES, R IV E R S, & O C E ANS The core federal law designed to control discharges of PFAS to surface waters is the Clean Water Act (CWA) .20 However, EPA has not adopted adequate regulations under the CWA to implement the law effectively and prevent this pollution .21 For example, the agency has yet to adopt national PFAS water quality criteria to protect human health in surface waters22 or establish Effluent Limitation Guidelines (ELGs), including pretreatment standards for industrial dischargers to wastewater treat- ment systems .23 These regulations are central to placing limits on PFAS discharges through National Pollutant Discharge Elimination System (NPDES)24 and industrial pretreatment permits .25 In October 2021, EPA released its PFAS Strategic Roadmap, outlining a whole-of-agency approach to addressing the toxic contaminants .26 While progress on the development of federal PFAS actions and standards stalls, states across the country are grappling with this “contamination crisis,”27 but state policies to address PFAS contamination are also limited and vary widely . Currently, at least 23 states have taken steps to address the problem through regulations, funding, and public health initiatives, though these measures are not yet comprehensive and vary widely in scope .”28 In April 2024, EPA established legally enforceable Maximum Contaminant Levels (MCLs)—primary standards that apply to public water systems—for six PFAS com- pounds in drinking water under the Safe Drinking Water Act (SDWA) .29 In May 2024, the agency designated PFOA and PFOS as hazardous substances under CERCLA30 (the Superfund law), enabling it to take cleanup actions and hold polluters accountable for costs .31 The follow- ing December, EPA proposed draft human health water quality criteria (HHWQC) to limit PFOA, PFOS, and PFBS in surface waters .32 While not yet finalized, these criteria represent concentrations which, if not exceeded, will protect the general population from adverse health effects due to ingesting water, fish, and shellfish . There is currently no proposed human health water quality criteria for other PFAS compounds . In May 2025, EPA announced its intent to extend com- pliance deadlines for the PFOA and PFOS MCLs, establish a federal exemption framework, and rescind regulatory determinations for PFHxS, PFNA, HFPO-DA (GenX), as well as the Hazard Index mixture that includes PFBS .33 These proposed changes do not have immediate legal effect and would require formal rulemaking, which could take years and likely face legal challenges . Additionally, the agency has yet to establish numeric limits or monitoring requirements for PFAS in biosolids under Section 405(d) of the CWA,34 despite being alerted to biosolids contamination by a major PFAS manufacturer as early as 2003 .35 Instead of taking regulatory action to address PFAS, EPA encouraged the use of biosolids as fertilizer, resulting in the widespread dispersal of the contaminants over millions of acres . The fertilizer industry estimates that farmers currently hold permits authorizing biosolid applications on approximately 70 million acres— about one-fifth of all U .S . agricultural land .36 Federal, state, and tribal governments must urgently monitor waterways, adopt enforceable standards to elimi- nate PFAS pollution sources, mitigate existing contamina- tion, and, where authorized to regulate discharges, ensure compliance through permitting and enforcement . They must also prioritize funding for PFAS monitoring and the installation of advanced treatment technologies to protect impacted communities—especially those disproportionately affected by PFAS and other toxic pollutants . The scale of this contamination and its risks to public and environmental health demand strong and immediate regulatory action . Common household products containing PFAS . 9 WATERKEEPER ALLIANCE | PFAS REPORT PHASE II CURRENT POLICY LANDSCAPE D E N T A L FLOSS MAKEU P & N AIL P O L I S HSKIN C A R E PROD U C T SS H A M POO P E S T I CIDES CAN D Y W RAPPE R S STAIN RESISTAN T F U RNITU R E & CARPETSWATER RE S IS T A NT PR O DUCTSMICROW A V E P O PCO R N BAGSCLEAN IN G P ROD U C T SP A I NTNONSTICK C O O KING E Q UI PMENTFOOD CO N T A I NERS & WRAPSFIREF IG H T ING F O A M 1. The U.S. surface waters tested are widely contaminated by many different types of regulated and unregulated PFAS. a . 98% of all surface water sampling sites tested upstream and downstream from WWTPs and biosolids land application fields in 19 states had one or more PFAS type detected, except for a single site downstream from a biosolids land application field in Wisconsin . b . More than half of the 40 PFAS chemicals that can be identified by EPA Method 1633 were detected in surface water samples upstream or downstream from WWTPs and biosolids land application fields . 2. Wastewater treatment plants and biosolids land appli- cation field discharges can be significant contributors of multiple types of PFAS to U.S. surface waters. a . The overwhelming majority of WWTPs evaluated lack enforceable PFAS limits in their CWA NPDES and other permits—both for discharges to surface waters and for biosolids applied to land application fields—underscor- ing the urgent need for regulatory standards to control these releases . b . 95% of downstream WWTPs sampling sites and 80% of downstream biosolids land application sites had elevated concentrations of multiple types of PFAS . c . Out of 40 types of PFAS that can be detected by EPA Method 1633, in comparison to PFAS levels detected at upstream sampling sites,37 the sampling detected 19 types of PFAS at elevated levels downstream from WWTPs and 14 types of PFAS at elevated levels down- stream from biosolids land application sites . Elevated PFAS Levels Detections Downstream from: Wastewater Treatment Plants38 Biosolids Land Application Sites PFHxA 19 6 PFOA 18 4 PFBS 17 7 PFPeA 17 6 PFHpA 14 6 PFHxS 14 3 PFOS 14 4 PFBA 12 7 PFNA 10 4 d . Multiple types of PFAS were also frequently detected at high concentrations downstream from WWTPs located in areas with multiple indicators of environmental and health burdens on disproportionately impacted commu- nities . For example: i . PFOA and PFOS were detected at the following concentrations in U .S . surface waters: State Waterbody Concentration (ppt) PFOA PFOS California Santa Ana River 13 12 Florida East Canal 7 .1 11 Michigan Rouge River 44 – North Carolina Haw River 10 23 Cape Fear River 8 .3 13 South Carolina Pocotaligo River 28 30 Texas Hunting Bayou 4 12 ii . PFPeA was responsible for the greatest increases in PFAS concentrations downstream from nine WWTPs and five biosolids land application fields . iii . PFHxA was also responsible for the greatest increases in PFAS concentrations downstream from five WWTPs . 3. Widespread detection of multiple PFAS types at upstream and downstream sampling sites confirms the need to regulate PFAS as a class to effectively limit exposure and address cumulative risks in U.S. surface waters. a . Certain types of PFAS were frequently detected at multi- ple upstream and downstream sampling sites . i . The most commonly detected PFAS at sites asso- ciated with WWTPs were PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFBS, PFHxS, and PFOS, which were all detected in 40 or more samples . ii . Some types of PFAS were often found to co-occur at individual sampling sites near WWTPs leading to higher overall exposures to total PFAS at those locations . For example, PFOS, PFHxA, PFOA, PFHxS, PFBS, PFHpA, PFPeA, PFBA, and PFNA were found to co-occur in 32 samples near WWTPs (and additional types of PFAS were often found at these locations as well) . KEY FINDINGS iii . Similarly, the most commonly detected PFAS at sites associated with biosolids land application fields were PFOA, PFBA, PFHxA, PFOS, PFHpA, PFBS, and PFHxS, each of which were detected in 19 or more samples . iv . Some types of PFAS were often found to co-occur at individual sampling sites near biosolids land application sites leading to higher overall expo- sures to total PFAS at those locations . For example, PFOA, PFBA, PFHxA, PFOS, PFHpA, PFBS, and PFHxA were found to co-occur in 16 samples near biosolids land application fields (additional types of PFAS were often found at these loca- tions as well) . b . The total downstream PFAS concentrations exceeded Environmental Working Group’s (EWG) health-based criteria for protecting against human health harm caused by total concentrations of PFAS (1 ppt) at all 22 WWTP sites and at 9 of 10 biosolids land application sites .39 c . The total PFAS concentration downstream from 17 WWTP sites and six biosolids land application sites increased, sometimes significantly, above total upstream PFAS concentrations . For example: i . In Oregon’s Tualatin River, the total PFAS con- centration increased from 0 .97 ppt upstream to 30 .02 ppt immediately downstream from the Rock Creek Water Resource Recovery Facility (WRRF) — a 2,994 .85% increase . ii . In Washington’s Dragoon Creek, the total PFAS concentration increased from 0 .63 ppt upstream to 32 .89 ppt immediately downstream from Spokane Riverside Park WRF’s biosolids land application fields—a 5,120 .63% increase . 4. Current regulations fail to control PFAS pollution of U.S. surface waters, leaving communities at risk for toxic chemical exposure. There are currently no federal surface water quality criteria or wastewater discharge limits for PFAS, and very few industrial dischargers are required to moni- tor or limit PFAS discharges into wastewater treatment systems—even though many industries contributing wastewater are likely handling, manufacturing, or using PFAS . At the time of sampling, PFAS concentrations downstream from WWTPs and biosolids land applica- tion fields often exceeded the current federal stan- dards, including Safe Drinking Water Act (SDWA) MCLs, the draft HHWQC, and the EWG health-based standards referenced in this report . i . The elevated downstream samples were equal to or exceeded the PFOA MCLs at 12 downstream WWTP sites and two downstream biosolids land application sites . ii . The elevated downstream samples exceeded the PFOS MCL at nine downstream WWTP sites and two downstream biosolids land application sites . iii . An elevated downstream sample exceeded the PFHxS MCL at one downstream WWTP site . EPA has not developed MCLs for most PFAS . iv . The elevated downstream samples exceeded the draft HHWQC (Water + Organism) for PFOA at 18 downstream WWTP sites and four downstream biosolids land application sites and the draft HHWQC (Water + Organism) for PFOS at 14 down- stream WWTP sites and four downstream biosolids land application sites . EPA has not developed HHWQC for most PFAS . v . Numerous EWG health-based criteria were exceeded in elevated samples from 29 locations downstream from WWTP sites and biosolids land application sites . PFOA, PFOS, PFHxS, and PFNA exceeded the criteria at the largest number of sites . 5. SiREM PFASsive™ samplers provide an accurate method for conducting fresh surface water sampling for PFAS in locations that are impacted by discharges from wastewater treatment plants and biosolids land application fields. These passive samples provide time-integrated data, giving a clearer picture of long-term contamination and PFAS bioavailability, toxicity, and risk—without the high cost and variability of daily or weekly grab samples . Waterkeeper groups successfully utilized the samplers across 19 states—producing results that are consistent and scientifically valid using EPA Method 1633 . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II WATERKEEPER ALLIANCE | PFAS REPORT PHASE II In April 2024, Waterkeeper Alliance, in collaboration with the Hispanic Access Foundation, initiated an extensive evaluation of selected watersheds previously sampled in the 2022 Phase I report . The goal was to identify WWTPs and biosolids land application sites that discharge near communities disproportionately impacted by environmental burdens, for more in-depth study . To determine these sites, the team utilized EPA’s EJScreen—a publicly available tool that integrates demographic and environmental indicators to assess environmental justice concerns across communities nationwide .40 METHODOLOGY Watershed Selection We initially identified 25 watersheds as high priority for participation in the PFAS Phase II monitoring project based on evaluations of the following criteria: • Waterkeeper group participation in the Phase I project Reporting of a Phase I PFAS result greater than 10 ppt and reporting multiple PFAS detections greater than 3 ppt • The presence of wastewater treatment facilities in proximity to the Phase I sampling site(s) • The existence of a Phase I sampling site upstream or downstream from the WWTP • The existence of approved industrial pretreatment and biosolids programs at the WWTP • Multiple EPA EJScreen Indicators greater than the 80th percentile within 1 mile of the WWTP41 • The compliance history of the WWTP • The inclusion of the WWTP in EPA’s PFAS Influent Study42 Facility Selection We then worked with Waterkeeper groups and Hispanic Access Foundation to finalize our selection of WWTPs and biosolids land application fields for sampling . Ultimately, we sampled 22 WWTP sites (25 WWTPs total) and 10 bio- solids land application sites in 19 states . These sites were located in, or discharged upstream from, areas within the Waterkeeper group’s watershed that, with limited exceptions, had multiple industrial users and where EPA EJScreen indicators were at or above the 80th percentile . The WWTP also had to discharge into a waterbody that could be sampled both upstream and downstream from publicly accessible locations or locations where access permission could be obtained . The selected biosolids land application fields were those that were associated with one of the selected WWTPs and either bordered a surface water or had ditches, streams, or other surface flow path- ways to a nearby surface water that had accessible, repre- sentative upstream and downstream sampling locations . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 13 Sampling Site Selection Given the ubiquity of PFAS and the importance of isolating these compounds associated with the WWTP or biosolids land application field in the sample results for this project, particular attention was given to defining and locating upstream and downstream sample sites . For the purposes of this project: “Biosolids” are treated sewage sludge, the solid byproduct of the wastewater treatment process . They must meet EPA standards for land application or other bene- ficial uses, as outlined in 40 CFR Part 503 . EPA classifies biosolids into two categories: Class A and Class B . Class A biosolids undergo treatment to eliminate pathogens and vector attraction, making them eligible for unrestricted land use under EPA standards, including for agriculture and landscaping . Class B biosolids are treated to reduce pathogens but may still contain detectable levels and are subject to restrictions, such as limiting public access and getting a permit to land apply . Both classes must meet requirements to address certain pollutants, including heavy metals, before being applied to land . At the time of publication, EPA has no standards or regulations for PFAS in biosolids .43 “Upstream” means a location on a waterbody that was above and not impacted by a pollution discharge from a targeted WWTP outfall or that was above a targeted biosolids application field . Upstream locations were gen- erally placed at least 100 feet, but no more than one mile upstream above the outfall discharge point or biosolids application field . Waterkeeper Alliance and Waterkeeper groups conducted site-specific evaluations of sampling locations to identify representative locations and con- sider making modifications to the distance restrictions as necessary to ensure a sampling location was represen- tative of conditions upstream from a WWTP or biosolids application field . Reasonable efforts were made to select accessible locations close enough to the outfall discharge point or biosolids application field to avoid as many other potential sources of PFAS pollution as possible . “Downstream” means a location on a waterbody that was below a targeted WWTP outfall or below a targeted biosolids land application field and was designed to be representative of surface water quality downstream from the discharge, as opposed to directly capturing a sample of the WWTP effluent or biosolids application runoff . The downstream location was generally placed at least 100 feet, but no more than one mile below the outfall dis- charge point or biosolids application field . Waterkeeper Alliance and Waterkeeper groups conducted site-specific evaluations of sampling locations to identify representa- tive locations and consider making modifications to the distance restrictions as necessary to ensure a sampling location was representative of conditions downstream from a WWTP or biosolids application field . Reasonable efforts were made to select accessible locations close enough to the outfall discharge point or biosolids applica- tion field to avoid as many other potential sources of PFAS pollution as possible . The discharge point for WWTP sampling locations was determined based on the GPS coordinates for the location of the WWTP outfall . To select sampling site locations, Waterkeeper Alliance and Waterkeeper groups evaluated publicly available information to identify outfall discharge points to waterbodies . Using ArcGIS mapping and data analysis, field investigations, and other mapping tools, Waterkeeper Alliance and Waterkeeper groups then iden- tified potential sampling sites on the waterbody that were located upstream and downstream of the WWTP outfall that were representative of waterbody conditions above and below the discharge . The discharge point for biosolids application sites was the downstream boundary of the field or ditch, whichever was the furthest downstream, where it inter- sected the waterbody . To select sampling sites for biosolids application fields, Waterkeeper Alliance and Waterkeeper groups evaluated publicly available infor- mation to identify the field boundaries and any ditches, streams, or surface water flow paths on or near the field . Using ArcGIS, field investigations, and other mapping tools, Waterkeeper Alliance and Waterkeeper groups then identified potential sampling sites on the receiving waterbody that were located upstream and downstream of the biosolids application field, that were representative of waterbody conditions above and below the biosolids application field . Sampling Method Waterkeeper Alliance developed a Sampling and Analysis Plan for Phase II that includes a description of the project, criteria for selecting participating Waterkeepers and sam- pling sites, details for collecting and managing information and data, requirements for training personnel, details on project management, standards and protocols for the col- lection and analysis of surface water samples using SiREM PFASsive™ passive samplers, and a Quality Assurance Project Plan (QAPP) to ensure the collection of reliable and representative water quality data that meet the project’s overall objectives and goals . Every effort was made to pro- cure PFAS-free sampling equipment and supplies for the project and to avoid cross-contamination in the shipping and handling of passive sampling devices, equipment, and supplies . Waterkeeper groups also received training regarding best practices for avoiding cross-contamina- tion while handling sampling devices, equipment, and supplies and during deployment, retrieval, transfer, and shipment of samples . PFASsive™ passive samplers were used for quantifica- tion of the freely dissolved concentration (Cfree) of targeted PFAS analytes in sediment pore water, surface water, and stormwater . The PFASsive™ samplers are used to quantify the Cfree of dissolved PFAS in surface water via an in-situ deployment near WWTPs and biosolids land application fields . PFASsive™ samplers use a volume of laboratory-sup- plied clean water in a sampling device separated from water by a permeable membrane . Freely dissolved PFAS analytes in the water diffuse across the membrane until the concentration of PFAS inside equilibrates with concentra- tions of freely dissolved PFAS in the water . The sampling device is then removed from the deployment location . The water inside the PFASsive™ sampler is collected and ana- lyzed like any other water sample using EPA methods . Water Quality Data Collection Waterkeeper Alliance conducted two training sessions for participating Waterkeeper groups in June 2024 . The webinars included an overview of SiREM PFASsive™ tech- nology, instruction on PFASsive™ sampling methodology and procedures, and equipment handling and shipping protocols . Upon completion of site selection and train- ing, each Waterkeeper group received a box of sampling devices, equipment, and supplies from Waterkeeper Alliance via U .S . mail . Inside the box was a cooler with two or four sealed bags containing four PFASsive™ vials within each bag, two or four PFASsive™ frames, multiple WATERKEEPER ALLIANCE | PFAS REPORT PHASE II METHODOLOGY METHODOLOGY WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 1514 Eurofins 125 ml HDPE sample bottles, laboratory-provided labels, PFAS-free gloves, and PFAS-free storage bags . Waterkeeper groups designated to conduct duplicate or field blank sampling received additional vial bags and bot- tles . Sampling personnel conducting field blanks received two additional laboratory bottles . Sampling personnel conducting duplicates received two additional full sets of sampling supplies—vial bags, sample bottles, frames, ice packs, and other equipment . One sampler was placed upstream of a WWTP and another was placed downstream from the same facility to evaluate discharges into the waterways .44 In situations where the WWTP land-applied biosolids from its waste- water treatment process, and it was selected for sampling, the Waterkeeper group also placed one device upstream and another downstream from a biosolids land applica- tion field to evaluate PFAS discharged into the waterway as a result of this waste management practice .45 Some Waterkeeper groups were also selected to collect dupli- cate samples or field blanks for quality control purposes . At the end of a deployment period of at least 20 days,46 Waterkeeper groups were responsible for retrieving the device, completing field data sheets and chain of custody forms, and transferring the sample to Eurofins . Laboratory Analysis and Equilibrium Calculations Upon retrieval, samples, including laboratory, duplicates, and field blanks, were sent to Eurofins Sacramento for analysis using EPA Method 1633, including an M2PFOA tracer . Three sets of four vials (without frames) were also used as tracer blanks and sent directly to the analytical laboratory from SiREM for analysis . The tracer blanks are analyzed using EPA Method 1633 to confirm that the source PFASsive™ water is PFAS-free and to determine the initial tracer concentration for the samplers (required for equilibrium calculations) . Eurofins Sacramento’s analytical results were reported first to SiREM Lab, which then completed equilibrium cal- culations prior to reporting the final results to Waterkeeper Alliance for further analysis and development of this report . Quantification of Cfree is dependent on the site-specific conditions surrounding each sampler that affect the sampling rates for each analyte . PFASsive™ uses an inert 13-C labeled PFOA (M2PFOA) tracer to evaluate the diffusion kinetics of the samplers during the exposure period . Cfree estimates of analytes that do not reach at least 10% of steady state concentrations in the sampler during deployment are reported with a qualifier . PFAS analytes were not expected to be qualified . Table 1 | Sampled Watersheds and Wastewater Treatment Facility Sites State City or County Waterkeeper Facility Receiving Waterbody NPDES Permit No. NPDES PFAS Effluent Limit AL Hoover Cahaba Riverkeeper Cahaba River Water Reclamation Facility (WRF)Cahaba River AL0023027 None Rainbow City Coosa Riverkeeper Rainbow City WWTP Big Wills Creek AL0056839 None CA Los Angeles LA Waterkeeper LA-Glendale Water Reclamation Plant Los Angeles River CA0053953 None Riverside Inland Empire Waterkeeper Riverside Regional Water Quality Control Plant Santa Ana River CA0105350 None CT Waterbury Long Island Soundkeeper Waterbury Water Pollution Control Facility Naugatuck River CT0100625 None FL Plant City Tampa Bay Waterkeeper Plant City WRF East Canal FL0026557 None GA Atlanta, Smyrna Chattahoochee Riverkeeper City of Atlanta’s R .M Clayton WRC Chattahoochee River GA0039012 NoneCobb County’s R .L . Sutton WRF GA0026140 West Area Water Quality Control Facility (WQCF)GA0038644 MD Frederick Potomac Riverkeeper City of Frederick WWTP Lower Monocacy River MD0021610 None MI Detroit Detroit Riverkeeper Great Lakes Water Authority Water Resource Recovery Facility Rouge River MI0022802 GoalPFOS 11 ppt PFOA WQBEL 8,040 ppt MS Jackson, Richland Pearl Riverkeeper Jackson Publicly Owned Treatment Works (POTW), Savanna Street Pearl River MS0024295 NoneWest Rankin Utility Authority WWTF MS0061743 NY/ NJ Rockland County, Hillburn Hackensack Riverkeeper Western Ramapo Advanced WWTP Ramapo River NY0270598 None Suffern Suffern (V) Sewage Treatment Plant (STP)NY0022748 None NC Fayetteville Cape Fear Riverkeeper Cross Creek WRF Cape Fear River NC0023957 None Graham Haw Riverkeeper Graham WWTP Haw River NC0021211 None OR Hillsboro Tualatin Riverkeepers Rock Creek WRRF Tualatin River OR0029777 None RI Cranston Narragansett Bay Riverkeeper Cranston WPCF Pawtuxet River RI0100013 None SC Sumter Black-Sampit Riverkeeper Sumter Pocotaligo River WWTP Pocotaligo River, East Branch SC0027707 None TX Houston Bayou City Waterkeeper Homestead WWTP Hunting Bayou TX0063029 None VA Petersburg James Riverkeeper South Central Wastewater Treatment Facility Appomattox River VA0025437 None WA Spokane Spokane Riverkeeper Spokane Riverside Park WRF Spokane River WA0024473 None WI Waukesha Milwaukee Riverkeeper City Of Waukesha WWTP Root River WI0029971 None WV Parkersburg West Virginia Headwaters Waterkeeper Parkersburg Utility Board Ohio River WV0023213 None Inwood Area Upper Potomac Riverkeeper Berkeley County PSSD — Inwood WWTP Opequon Creek WV0082759 None Table 2 | Sampled Watersheds and Biosolids Land Application Fields State Waterkeeper Facility Biosolids Site Watershed PFAS Limit AL Cahaba Riverkeeper Cahaba River WRF (combined with Valley Creek WRF)Cane Creek None Coosa Riverkeeper Rainbow City WWTP Whippoorwill Creek None MD Potomac Riverkeeper Synagro Multi-WWTP Site (inc. City of Frederick WWTP) Monocacy River Recommended Limits MS Pearl Riverkeeper Jackson POTW, Savanna Street Big Creek and Pearl River None NC Cape Fear Riverkeeper Cross Creek WRF South River None Haw Riverkeeper Graham WWTP Haw Creek None VA James Riverkeeper Synagro Multi-WWTP Site (inc. South Central Wastewater Authority WWTF) Old Town Creek None WA Spokane Riverkeeper Spokane Riverside Park WRF Dragoon Creek None WI Milwaukee Riverkeeper City of Waukesha WWTP Spring Creek (Fox River Watershed) None — Statewide Interim Strategy WV Upper Potomac Riverkeeper Berkeley County PSSD Back Creek None Synagro obtains biosolids from multiple WWTPs and, as a result, land application events may contain biosolids from one or more of those facilities . Jackson POTW, Trahon and Big Creek WWTF also discharges to Big Creek above the confluence with Pearl River . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II METHODOLOGY METHODOLOGY WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 1716 Data Quality All of the data collected in this project were evaluated in accordance with a QAPP to evaluate whether the sampling produced quality data that is accurate, precise, complete, and representative, including: 1 . adherence to consistent and reliable methods, 2 . the analytical data meets data quality objectives (DQOs), and 3 . the analytical data generated was reviewed, validated, and verified . Although PFAS concentrations in surface water can be influenced by various factors—such as other discharges, atmospheric deposition, weather, and sampling timing— the upstream and downstream sites in this report were selected based on protocols designed to ensure repre- sentative sampling and minimize outside influences . Sites were placed near the discharge point or biosolids appli- cation area, and passive sampling over multiple days was used to reduce the impact of environmental variability . As a result, the findings are considered representative of PFAS impacts from wastewater treatment plant discharges and biosolids land application . While other influences cannot be entirely ruled out, there are no indications that they significantly affected the results given the study design . Other potential influences that we identified for a location, if any, are noted separately for each individual Waterkeeper group in the Evaluation of Facilities and Watersheds section of this report below . As part of the review process, a Ph .D . scientist from SiREM evaluated all submitted data before modeling was performed and no abnormalities or flags reflecting on the reliability of the data were observed . The data evalu- ation and usability determination required by the QAPP confirmed that the data collected during this project accurately measured PFAS levels associated with the wastewater treatment facility and biosolids application field discharges identified for assessment and are suit- able for use in the Project Report . The data evaluation, including any deviations from the Sampling and Analysis Plan, the assessment of Quality Control sample results, data assessment and laboratory qualifiers, and site con- dition impacts, is documented in the Data Evaluation and Usability Report . All Eurofins laboratory Result Qualifiers are shown in the Qualifier column next to the Results column in Appendix A; however, none of the qualifiers adversely impact the usability of the results for the pur- poses of this report . Third Party Review This report was submitted for third-party review with two experts to obtain an evaluation of the accuracy of the data and data analysis . Table 3 | EPA Method 1633 Target Analytes Analyte Description CAS Number ADONA 4,8-Dioxa-3H-perfluorononanoic acid 919005-14-4 FOSA perfluorooctanesulfonamide 754-91-6 HFPO-DA (GenX)Hexafluoropropylene oxide-dimer acid 13252-13-6 NEtFOSAA N-ethyl perfluorooctane sulfonamido acetic acid 2991-50-6 NEtFOSE N-ethyl perfluorooctane sulfonamido ethanol 1691-99-2 NEtFOSA N-ethylperfluorooctane-1-sulfonamide 4151-50-2 NFDHA perfluoro-3,6-dioxaheptanoic acid 151772-58-6 NMeFOSA N-methylperfluoro-1-octanesulfonamide 31506-32-8 NMeFOSAA N-methyl perfluorooctane sulfonamido acetic acid 2355-31-9 NMeFOSE N-methyl perfluorooctane sulfonamido ethanol 24448-09-7 PFBA perfluorobutanoic acid 375-22-4 PFBS perfluorobutanesulfonic acid 375-73-5 PFDA perfluorodecanoic acid 335-76-2 PFDoA perfluorododecanoic acid 307-55-1 PFDoS perfluorododecanesulfonic acid 79780-39-5 PFDS perfluorodecanesulfonic acid 335-77-3 PFEESA perfluoro(2-ethoxyethane)sulphonic acid 113507-82-7 PFHpA perfluoroheptanoic acid 375-85-9 PFHpS perfluoroheptanesulfonic acid 375-92-8 PFHxA perfluorohexanoic acid 307-24-4 PFHxS perfluorohexanesulfonic acid 355-46-4 PFMBA perfluoro-4-methoxybutanoic acid 863090-89-5 PFMPA perfluoro-3-methoxypropanoic acid 377-73-1 PFNA perfluorononanoic acid 375-95-1 PFNS perfluorononanesulfonic acid 68259-12-1 PFOA perfluorooctanoic acid 335-67-1 PFOS perfluorooctanesulfonic acid 1763-23-1 PFPeA perfluoropentanoic acid 2706-90-3 PFPeS perfluoropentanesulfonic acid 2706-91-4 PFTeA perfluorotetradecanoic acid 376-06-7 PFTriA perfluorotridecanoic acid 72629-94-8 PFUnA perfluoroundecanoic acid 2058-94-8 9Cl-PF3ONS 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (F-53B major)756426-58-1 11Cl-PF3OUdS 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (F-53B minor)763051-92-9 3:3 FTCA 3-perfluoropropyl propanoic acid 356-02-5 4:2 FTSA 4:2 fluorotelomer sulfonic acid 757124-72-4 5:3 FTCA 2H, 2H, 3H, 3H-perfluorooctanoic acid 914637-49-3 6:2 FTSA 6:2 fluorotelomer sulfonic acid 27619-97-2 7:3 FTCA 2H, 2H, 3H, 3H-perfluorodecanoic acid 812-70-4 8:2 FTSA 6:2 fluorotelomer sulfonic acid 39108-34-4 WATERKEEPER ALLIANCE | PFAS REPORT PHASE II METHODOLOGY METHODOLOGY WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 1918 we sampled at WWTP sites received influent from one or more identified industrial users and many likely had additional industrial dischargers that the EPA has identified as “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemi- cals,”53 but only one wastewater treatment system had a pretreatment program to place limits on the amount of certain PFAS that industrial users could discharge into its treatment plant .54 According to EPA, statewide surveys have found PFOS and PFOA in biosolids originating from industrial and non-industrial sources discharging to WWTPs across the country .55 To the best of our knowledge, none of the WWTPs identified in this report have installed treatment technologies to remove PFAS from either their waste- water discharged to surface waters or their biosolids . Furthermore, the majority of the facilities we evaluated are not required to monitor or limit PFAS levels in bio- solids prior to land application or other disposal meth- ods for treated or untreated sewage sludge . Traditional wastewater treatment technology does not remove or destroy PFOS and PFOA, and, as a result, a portion of the PFAS will accumulate in biosolids generated during the treatment process .56 Controlling PFAS at the source is essential . CWA permitting authorities and industrial pretreatment pro- grams must be utilized to require industrial dischargers to remove PFAS before releasing effluent into the envi- ronment or sending it to WWTPs .57 The data collected in this monitoring project and discussed below provide strong evidence of the immediate need for EPA, states, and tribes to take those actions . The data also highlight the urgent need to direct federal infrastructure funding to municipal wastewater treatment systems in areas with multiple indicators of environmental and health burdens on disproportionately impacted communities, to support treatment upgrades and safe biosolids management that protect human health and the environment . The Phase I PFAS monitoring project, undertaken with 113 U .S . Waterkeepers from across the country, was a first-of-its-kind nationwide survey of surface waters47 that unequivocally demonstrated that dangerous PFAS pol- lution is widespread in surface waters across the country . In some locations, PFAS concentrations were thousands to hundreds of thousands times higher than what EPA experts say is safe for drinking water . PFAS must be controlled and removed at their source in order to protect human health from these dangerous toxic chemicals, but this is not happening due to the lack of federal and state requirements for industrial dischargers and passive receivers like WWTPs and, particularly in dis- proportionately-impacted communities, the lack of fund- ing to install advanced treatment systems to remove PFAS . Additionally, there are no state, tribal, and federal surface water quality or drinking water standards for most PFAS . In 2024, EPA established legally enforceable limits for just six types of PFAS in drinking water, known as Maximum Contaminant Levels (MCLs) and proposed draft Human Health Water Quality Criteria (HHWQC) to limit three types of PFAS in surface waters .48 At the time of publication of this report, EPA has not proposed drinking water or surface water limits for any other types of PFAS or any regulatory standards to address PFAS in biosolids .49 Although EPA appears to have been aware of PFAS in biosolids since at least 2003, it has been reported that the agency actively encouraged the use of biosolids as fertil- izer and it is estimated that farmers have obtained permits authorizing biosolids application on nearly 70 million acres of farmland, or about a fifth of all agricultural land in the U .S .50 At the same time, states across the country are grappling with this “contamination crisis,”51 but state poli- cies to address PFAS contamination vary widely through- out the country .52 To address the urgent need for additional policy reform and scientifically sound data on PFAS sources and surface water contamination, Waterkeeper Alliance and Hispanic Access Foundation designed this Phase II PFAS monitoring project to work with U .S . Waterkeepers and partners . The project aims to evaluate and quantify PFAS contamination over time in surface waters using passive samplers placed near identified municipal wastewater treatment systems and biosolids application fields, with a focus on areas that appear to be disproportionately impacted based on the identification of EJScreen indicators above the 80th per- centile . SiREM PFASsive™ samplers were selected for the project to provide an accurate representation of PFAS con- tamination present in the sampled surface waters and to be more reflective of bioavailability, toxicity, and risk than the data that would have been obtained through collection of a traditional single-day grab sample at each location . Discharges from WWTPs and biosolids land applica- tion fields were indicated as a source of PFAS contami- nation in U .S . surface waters at nearly every downstream location we tested in 19 states, but we identified only one wastewater treatment system that has a limit on the amount of PFAS they could discharge into surface waters in their Clean Water Act NPDES permit, and we identi- fied only seven facilities had a requirement to monitor their discharges for PFAS . See Table 1 (p. 16) and Table 2 (p. 17) . At least 22 of the 25 WWTPs where ANALYSIS AND FINDINGS East Canal, FL Big Wills Creek, AL Root River, WI Ohio River, WV Ramapo River, NY Naugatuck River, CT Pawtuxet River, RI Appomattox River, VA Haw River, NC Chattahoochee River, GA Cape Fear River, NC Pocotaligo River, SC Opequon Creek, WV Lower Monocacy River, MD Rouge River, MI Cahaba River, AL Pearl River, MS Hunting Bayou, TX Santa Ana River, CA Los Angeles River, CA Spokane River, WA Tualatin River, OR Figure 1 | Phase II PFAS Sampling Sites Figure 2 | Phase I Sampling Sites WWTP Water Sampling Sites – Phase II Biosolids Land Application Sites – Phase II Phase I Sampling Sites Table 4 | PFAS Types Detected at One or More Sites Analyte Site Type 1 PFOS WWTP and Biosolids 2 PFHxA WWTP and Biosolids 3 PFHpS Biosolids Site 4 PFOA WWTP and Biosolids 5 PFHxS WWTP and Biosolids 6 PFBS WWTP and Biosolids 7 PFPeA WWTP and Biosolids 8 PFHpA WWTP and Biosolids 9 PFBA WWTP and Biosolids 10 PFNA WWTP and Biosolids 11 PFDA WWTP and Biosolids 12 PFPeS WWTP and Biosolids 13 6:2 FTS WWTP 14 FOSA WWTP and Biosolids 15 PFUnA WWTP 16 HFPO-DA (Gen-X)WWTP and Biosolids 17 PFMPA WWTP 18 PFDoA WWTP 19 8:2 FTS WWTP 20 NMeFOSAA WWTP 21 NEtFOSAA WWTP 22 PFTeA WWTP 23 PFMBA WWTP WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 2120 Method Evaluation SiREM PFASsive™ samplers provide an effective method for conducting fresh surface water PFAS sampling that pro- duce scientifically valid data in locations that are impacted by discharges from WWTPs and biosolids land applica- tion fields . With proper training provided by the SiREM PFASsive™ manufacturer, the devices were successfully deployed and retrieved by Waterkeeper groups in a wide variety of locations across the U .S . SiREM PFASsive™ devices produced water samples that were analyzed by Eurofins Sacramento using the current approved EPA Method 1633 without any limita- tions attributable to the passive sampling device . A com- parative analysis of the data demonstrated that SiREM PFASsive™ samplers produced reliable, consistent water quality data that was comparable between all sites despite the geographic, geomorphic, and hydrologic differ- ences in watersheds . The SiREM PFASsive™ passive sampling methodology captured time-integrated measurements of PFAS levels over periods of at least 20 days . Such measurements pro- vide a more accurate representation of PFAS contamination and risk than traditional grab sample methods, which reflect PFAS concentrations that represent the entire mass of PFAS present at a single point in time and may result in an over- estimation of the bioavailable PFAS exposure to human and ecological receptors . By collecting PFAS data over a longer period, understanding of PFAS migration, bioavailability, and impacts is enhanced, while also shedding light on the effectiveness of WWTP processes and land application methods in controlling or contributing to PFAS release into surface waters . The time-integrated measurements of PFAS concentrations over periods of at least 14 days is more practical and cost-effective than the alternative of collect- ing multiple samples on a daily or even weekly or monthly basis . This would require additional time and expendi- tures to collect multiple samples in the field, analyze those samples in a laboratory, and analyze multiple results for a single location . The equilibrium concentrations generated through the use of SiREM PFASsive™ samplers provide a more accurate representation of PFAS contamination present in the sampled surface waters, and are more reflective of bioavailability, toxicity, and risk, than traditional single-day grab sample methods that may capture higher or lower values depending on the time of collection . Because PFAS are persistent, bioaccumulative, and toxic, it is critical to understand their migration pathways and bioavailability for proper delineation and risk characterization . Passive sam- pling in surface water is an accepted approach to assess bioavailability and risk .58 The SiREM PFASsive™ passive sampler “is a diffusion-based equilibrium passive sam- pler that was developed and validated for relevant PFAS (EPA 537, EPA 1633) in porewater and surface water .”59 After retrieving the SiREM PFASsive™ device, the water col- lected in the sampler is treated like any other water sample allowing the PFAS to be concentrated and measured using EPA analysis methods “without the additional extraction steps required for sorbents” and the “results are presented as concentrations in nanograms per liter (ng/L) .”60 A reverse tracer in the devices also “allows the extent of equilibrium to be determined during deployment and used to estimate the freely dissolved equilibrium concentration in the envi- ronment . The freely dissolved equilibrium concentration has been shown to relate better to bioavailability, toxicity, and risk assessment models than concentrations measured from conventional grab samples .”61 ELEVATED DOWNSTREAM WWTP SITE RESULTS as shown in Table 5 (p. 23): PFOA DETECTION 44 ppt Rouge River, MI 28 ppt Pocotaligo River, SC 13 ppt Santa Ana River, CA 10 ppt Haw River, NC PFPeA DETECTION 43 ppt Santa Ana River, CA 38 ppt Pocotaligo River, SC 36 ppt Haw River, NC 22 ppt Monocacy River, MD 20 ppt Los Angeles River, CA 18 ppt Root River, WI PFHxA DETECTION 49 ppt Pocotaligo River, SC 27 ppt Santa Ana River, CA 27 ppt Haw River, NC 20 ppt Los Angeles River, CA PFOS DETECTION 30 ppt Pocotaligo River, SC 23 ppt Haw River, NC 13 ppt Cape Fear River, NC 12 ppt Santa Ana River, CA 12 ppt Hunting Bayou, TX 11 ppt East Canal, FL Table 5 | Elevated Sample Values Downstream from WWTPs (ppt) State Waterkeeper/ Waterbody Wastewater Treatment Plant PFAS Analyte (ppt)PFOAPFHxAPFBSPFPeAPFHpAPFHxSPFOSPFBAPFNAPFDAPFPeSFOSAPFUnAPFDoA6:2 FTSPFMPAPFTeA NMeFOSAAPFMBAAL Cahaba Riverkeeper Cahaba River Cahaba River WRF 4.9 6.4 6.4 10.0 1.9 1.5 Coosa Riverkeeper Big Wills Creek Rainbow City WWTP 2.2 0.6 1.9 1.6 CA Inland Empire Waterkeeper Santa Ana River Riverside RWQCP Nov.27.0 43.0 Aug. 13.0 20.0 21.0 24.0 3.6 12.0 2.1 6.1 LA Waterkeeper Los Angeles River LA-Glendale WRP 20.0 20.0 3.3 9.8 2.1 CT Long Island Soundkeeper Naugatuck River Waterbury WPCF 8.9 3.1 8.1 2.6 1.7 8.3 4.8 FL Tampa Bay Waterkeeper East Canal Plant City WRF 7.1 6.3 6.0 9.9 3.7 3.9 11.0 9.0 1.3 0.71 GA Chattahoochee Riverkeeper Chattahoochee River Clayton, Sutton, West Area 2.8 4.6 4.3 6.1 1.5 2.1 1.2 2.1 4.1 MD Potomac Riverkeeper Monocacy River City of Frederick WWTP 6.8 13.0 5.0 22.0 2.5 2.5 4.4 0.62 MI Detroit Riverkeeper Rouge River Great Lakes Water Authority Water Resource Recovery Facility (GLWA WRRF) 44.0 9.2 16.0 3.1 5.0 MS Pearl Riverkeeper Pearl River Jackson POTW, Savanna Street / West Rankin Utility Authority WWTF 2.9 4.4 3.0 1.3 1.3 3.5 3.6 0.71 NC Cape Fear Riverkeeper Cape Fear River Cross Creek WRF 8.3 6.7 4.7 8.6 3.7 5.3 13.0 5.4 0.94 Haw Riverkeeper Haw River Graham WWTP 10.0 27.0 17.0 36.0 8.8 4.5 23.0 9.2 2.2 2.6 0.87 0.59 1.1 0.88 NJ Hackensack Riverkeeper Ramapo River Western Ramapo Advanced WWTP / Suffern (V) STP Nov.6.7 10.0 2.5 3.5 4.7 OR Tualatin Riverkeepers Tualatin River Rock Creek WRRF 3.3 7.1 3.5 4.4 1.7 0.73 2.5 6.2 0.59 RI Narragansett Bay Riverkeeper Pawtuxet River Cranston WPCF ©5.7 4.9 2.3 2.1 SC Black-Sampit Riverkeeper Pocotaligo River Sumter Pocotaligo River WWTP 28.0 49.0 5.5 38.0 21.0 30.0 12.0 2.3 2.1 1.7 0.79 22.0 1.1 TX Bayou City Waterkeeper Hunting Bayou Homestead WWTP 4.0 11.0 11.0 9.3 12.0 1.3 0.64 VA James Riverkeeper Appomattox River South Central Wastewater Authority WWTF 2.6 2.3 4.4 2.6 0.75 WA Spokane Riverkeeper Spokane River Spokane Riverside Park WRF 1.1 2.0 0.8 2.1 WI Milwaukee Riverkeeper Root River City of Waukesha WWTP ©8.0 7.6 4.8 18.0 1.9 2.1 5.0 6.5 1.3 0.83 WV Upper Potomac Riverkeeper Opequon Creek Berkeley County PSSD — Inwood WWTP 4.1 7.2 9.3 9.3 West Virginia Headwaters Waterkeeper Ohio River Parkersburg Utility Board 1.6 Includes all downstream sample results where the downstream value exceeded the upstream value except where as noted with an did not have upstream samples . © Combined: The result represents the highest concentration in either the primary or duplicate sample . City of Atlanta’s R .M Clayton WRC, Cobb County’s R .L . Sutton WRF, and West Area Water Quality Control Facility (WQCF) WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 2322 Overview of Results for WWTPs and Biosolids Land Application Fields The sampling data collected through this project con- firmed, consistent with the results of our Phase I sampling, that U .S . surface waters are widely contaminated by many different types of PFAS . Although we sampled fewer waterways in this project than in the previous monitoring project, we found that one or more PFAS were detected at all surface water sampling sites tested both upstream and downstream from WWTPs and biosolids land application fields in 19 states, with the exception of a single site down- stream from a biosolids land application field in Wisconsin . See Appendix A. The sampling results also indicated the widespread presence of multiple types of PFAS in U .S . surface waters . Out of 40 types of PFAS detected by EPA Method 1633, 23 types of PFAS were detected in upstream or down- stream surface water sampling sites . PFAS Surface Water Contamination from WWTPs and Biosolids Land Application Fields The sampling data collected in the project clearly demonstrate that discharges of PFAS from multiple WWTPs and biosolids land application fields that we evaluated are contributing multiple types of PFAS to U .S . surface waters . By comparing upstream and down- stream results, we determined that elevated concentra- tions of multiple types of PFAS were detected at 21 of 22 downstream WWTP sampling sites62 and at 8 of the 10 downstream biosolids land application sampling sites . See Table 563 (p. 23) and Table 6 (below). Pearl River biosolids site sampling results reported and analyzed below include any PFAS contributed by Jackson POTW’s biosolids land application fields and the Trahon and Big Creek WWTF to Big Creek above its confluence with the Pearl River . Table 6 | Elevated Sample Values Downstream from Biosolids Land Application Fields64 State Waterbody PFAS Analyte (ppt)PFBAPFBSPFPeAPFHxAPFHpAPFOAPFNAPFOSPFHxSPFDAFOSAPFPeSPFHpSHFPO-DA (GenX)AL Cane Creek © 11.00 2.70 11.00 4.20 1.70 4.10 0.68 5.80 MD Monocacy River 6.20 3.90 4.90 2.20 0.77 MS Pearl River 13.00 3.60 0.73 NC Haw Creek 3.90 5.30 1.90 0.81 2.20 1.30 South River © 6.70 5.50 4.80 3.20 2.80 5.80 1.40 7.50 2.40 0.86 0.94 VA Old Town Creek 1.30 1.30 1.70 1.70 0.81 3.90 3.10 1.50 WA Dragoon Creek 3.10 5.80 12.00 7.40 1.50 1.50 0.71 0.88 WV Back Creek © 2.50 2.50 1.40 3.10 1.00 Includes all downstream sample results where the downstream value exceeded the upstream value except where as noted with an did not have upstream samples . © Combined: The result represents the highest concentration in either the primary or duplicate sample . Jackson POTW, Trahon, and Big Creek WWTF also discharges to the sampled waterway through Big Creek and could have contributed PFAS to the downstream sample results . Figure 3 | Number of Elevated Downstream PFAS Detections at WWTP Sites, by Analyte PFHxA PFOA PFBS PFPeA PFHpA PFHxS PFOS PFBA PFNA PFDA FOSA PFPeS PFUnA PFDoA 6:2 FTS PFMPA PFTeA NMeFOSAA PFMBA 19 18 17 17 14 14 14 12 10 6 3 2 2 2 2 2 1 1 1PFAS ANALYTENUMBER OF DETECTIONS 2 4 6 8 10 12 14 16 18 20 — — — — — — — — — — — — — — — — — — — — WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 2524 Wastewater Treatment Plants Out of 40 types of PFAS detected by EPA Method 1633, 19 types of PFAS at elevated levels were detected down- stream from WWTPs . The most frequently detected PFAS at elevated levels downstream from wastewater treatment plants include PFHxA (19 detections), PFOA (18 detec- tions), PFBS and PFPeA (17 detections), PFHpA, PFHxS, and PFOS (14 detections), PFBA (12 detections), and PFNA (10 detections) . See Figure 3 (p. 25). The highest elevated concentration of PFAS down- stream from a WWTP was PFHxA at 49 ppt in the Pocotaligo River below the Sumter Pocotaligo River WWTP in South Carolina . PFHxA was detected in 19 sam- ples downstream from WWTPs and the mean concentra- tion of all values combined was 13 .02 ppt . PFOA was also detected in 18 samples taken downstream from WWTPs, with a mean concentration of 8 .88 ppt for all sites and the highest elevated concentration, 44 ppt, was found in the Rouge River below the GLWA WRRF in Michigan . See Table 7 (below). Multiple types of PFAS were also frequently detected, often at high concentrations, at elevated levels at a single sampling site downstream from each WWTP, presenting unacceptable, cumulative risks to communities with multi- ple EJScreen Indexes that exceed the 80th percentile . For example, 14 types of PFAS were detected at the sampling site in the Haw River downstream from a Graham WWTP outfall in North Carolina, 13 types of PFAS were detected at the sampling site in the Pocotaligo River downstream from a Sumter Pocotaligo River WWTP outfall in South Carolina, and 10 types of PFAS were detected at the sam- pling site in the Root River downstream from a Waukesha WWTP outfall in Wisconsin . See Figure 4 (p. 27). Pocotaligo River | SC Haw River | NC Root River | WI Tualatin River | OR Chattahoochee River | GA Cape Fear River | NC Monocacy River | MD Hunting Bayou | TX Naugatuck River | CT Cahaba River | AL Rouge River | Ml Ramapo River | NJ Los Angeles River | CA Appomattox River | VA Spokane River | WA Opequon Creek | WV Pawtuxet River | RI Big Wills Creek | AL Santa Ana River | CA Ohio River | WV 14 13 10 9 9 9 8 7 7 6 5 5 [Nov.] 5 5 4 4 4 4 2 [Nov.] 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14SAMPLING SITENUMBER OF TYPES OF PFAS Figure 4 | Number of Different PFAS Types Elevated Downstream from WWTPs Comparing Upstream/Downstream Sample Results Table 7 | PFAS Concentrations and Watersheds with Highest Detection for Each Analyte Downstream from WWTPs Maximum, Minimum, and Mean Analyte Watershed with Highest Elevated Detection Elevated Downstream Detection (ppt) Number of Detections Mean Minimum Maximum PFHxA Pocotaligo River 19 13 .02 2 49 PFOA Rouge River 18 8 .88 1 .1 44 PFPeA Santa Ana River 17 16 .28 4 .4 43 PFOS Pocotaligo River 14 9 .49 2 .1 30 6:2 FTS Pocotaligo River 2 11 .55 1 .1 22 PFBS Santa Ana River 17 6 .53 1 .6 21 PFHpA Pocotaligo River 14 4 .46 1 .3 21 PFHxS Rouge River 14 0 .64 0 .64 16 PFBA Pocotaligo River 12 6 .24 1 .9 12 PFMBA Santa Ana River 1 6 .1 6 .1 6 .1 PFDA Rouge River 6 2 .21 0 .64 5 PFTeA Chattahoochee River 1 4 .1 4 .1 4 .1 PFNA Pocotaligo River 10 1 .47 0 .59 2 .3 PFMPA Chattahoochee River 2 1 .49 0 .88 2 .1 FOSA Pocotaligo River 3 1 .31 0 .62 1 .7 PFDoA Chattahoochee River 2 0 .9 0 .59 1 .2 PFPeS Cape Fear River 2 0 .83 0 .71 0 .94 NMeFOSAA Pocotaligo River 1 1 .1 1 .1 1 .1 PFUnA Haw River 2 0 .83 0 .79 0 .87 WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 2726 Specific PFAS Types As shown in Figure 7 [WWTP Sites] and Figure 8 [Biosolids Sites], PFPeA was responsible for the greatest increases in PFAS concentrations downstream from nine WWTPs and five biosolids land application fields . PFHxA was respon- sible for the greatest increases in PFAS concentrations downstream from five WWTPs . Notably, these types of PFAS are neither regulated by EPA nor included in the draft HHWQC .65 These two compounds are also not regu- lated as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)66 or the SDWA .67 As for the other PFAS respon- sible for the greatest increases at other WWTPs, EPA has only established MCLs for PFOA, PFOS, and PFHxS and a Hazard Index value for a mixture containing two or more of PFHxS, PFNA, HFPO-DA, and PFBS . EPA has also proposed draft HHWQC for PFOA, PFOS, and PFBS .68 Biosolids Land Application Fields Out of 40 types of PFAS detected by EPA Method 1633, in comparison to PFAS levels detected at upstream sampling sites, the sampling detected 14 types of PFAS at elevated levels downstream from biosolids land application sites . The most frequently detected PFAS at elevated levels downstream from biosolids land applica- tion sites include PFBA and PFBS (7 detections), PFPeA, PFHxA, and PFHpA (6 detections), and PFOA, PFNA, and PFOS (4 detections) . See Figure 5 (below). PFPeA was detected at elevated levels at six of the 10 biosolids land application sites, with a mean concentra- tion of 7 .32 ppt for all sites . PFBA was detected at elevated levels downstream from seven biosolids land application sites with a mean concentration of 4 .96 ppt for all sites and the highest elevated concentration, 11 ppt, was found in Cane Creek below the Beltona Mine Land Reclamation Site in Alabama . See Figure 6 (below). Figure 8 | PFAS Analytes with Greatest Downstream Increase in Concentration by Number of Watersheds Upstream and Downstream Comparison at Biosolids Land Application Fields Figure 7 | PFAS Analytes with Greatest Downstream Concentration Increase by Number of Watersheds Upstream and Downstream Comparison at Wastewater Treatment Plants PFPeA 45% PFHxA 25% PFBS 12 .5% PFNA 12 .5% PFOA 12 .5% PFPeA 62 .5% FOSA 5% PFBS 5% PFHxS 5% PFOA 5%PFOS 5% PFTeA 5% 9 5 1 1 1 111 1 1 15 Figure 6 | Biosolids Application Fields Maximum and Mean Concentrations of Elevated PFAS Downstream from All Sites Figure 5 | Number of Elevated Downstream PFAS Detections at Biosolid Sampling Sites by Analyte PFBA PFBS PFPeA PFHxA PFHpA PFOA PFNA PFOS PFHxS PFDA FOSA PFPeS PFHpS HFPO-DA (Gen X) 7 7 6 6 6 4 4 4 3 2 2 1 1 1 11.00 5.80 13.00 7.40 2.80 5.80 1.90 7.50 2.40 0.81 0.88 2.20 1.30 0.94 4.96 3.86 7.32 4.08 1.67 3.83 1.19 5.00 1.54 0.77 0.87 2.20 1.30 0.94 8 7 6 5 4 3 2 1 2 4 6 8 10 12 14 16 NUMBER OF DETECTIONS CONCENTRATION LEVELS (ppt) Maximum Elevated Downstream Detection (ppt) Mean Elevated Downstream Detections (ppt) EPA PFOA/PFOS MCL (ppt) — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 2928 As shown in Table 9 (left), downstream from biosolids land application fields: ALABAMA In Black Warrior Riverkeeper’s watershed, PFPeA increased by 11 ppt in the Cane Creek below the Jefferson County Commission WWTPs’ biosolids application site in Alabama . WASHINGTON In Spokane Riverkeeper’s watershed, PFPeA increased by 12 ppt in the Dragoon Creek below the Spokane Riverside Park WRF’s biosolids applica- tion fields in Washington . As shown in Table 8 (above), downstream from WWTPs: CALIFORNIA In Inland Empire Waterkeeper’s watershed, PFPeA increased by 31 ppt in the Santa Ana River below the Riverside RWQCP’s outfall in California . NORTH CAROLINA In Haw Riverkeeper’s watershed, PFPeA increased by 22 ppt in the Haw River below the City of Graham WWTP’s outfall in North Carolina . SOUTH CAROLINA In Black-Sampit Riverkeeper’s watershed, PFHxA increased by 39 .4 ppt in the Pocotaligo River below the Sumter Pocotaligo River Plant outfall in South Carolina . Total PFAS Concentrations The data collected in this project demonstrates that it is imperative for PFAS to be regulated as a class, as opposed to solely as individual chemicals, in order to effectively control widespread exposure and address the risks posed by combined exposures to multiple PFAS chemicals in U .S . surface waters .69 Regulating PFAS on a compound-by-compound basis has left thousands of PFAS chemicals completely unregulated . As our data demonstrate, multiple types of PFAS often co-occur at a single location and unregulated PFAS are often present at high concentrations . The presence of multiple types of PFAS heightens human exposure risk since PFAS mixtures may have additive and synergistic effects .”70 Moreover, the harmful effects of PFAS exposure may be “more related to total PFAS levels, rather than individual PFAS compounds .”71 In this project, the most frequently detected PFAS in upstream and downstream samples tended to co-occur at multiple locations leading to high overall exposure to total PFAS at those locations . For example, as shown in Figure 9 (p. 32), PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFBS, PFHxS, and PFOS were detected in 40 or more samples near WWTPs . In 32 samples, the sampling detected PFOS, PFHxA, PFOA, PFHxS, PFBS, PFPeA, PFHpA, PFBA, and PFNA (often as well as other PFAS) at that single location . See Appendix A. Table 9 | PFAS Analytes with Greatest Concentration Increase in Downstream Biosolids Site Samples State Waterbody Waterkeeper PFAS Analyte wth Greatest Increase Amount of Increase (ppt) AL Cane Creek ©Cahaba Riverkeeper and Black Warrior Riverkeeper PFPeA 11 Whippoorwill Creek Coosa Riverkeeper No Increase MD Monocacy River Potomac Riverkeeper PFNA 0 .77 MS Pearl River Pearl Riverkeeper PFPeA 1 NC South River ©Cape Fear Riverkeeper PFPeA 4 .8 Haw Creek Haw Riverkeeper PFBS 5 .3 VA Old Town Creek James Riverkeeper PFOA 3 .9 WA Dragoon Creek Spokane Riverkeeper PFPeA 12 WI Spring Creek Milwaukee Riverkeeper No Increase WV Back Creek ©Upper Potomac Riverkeeper PFPeA 1 .4 © Combined: The result represents the highest concentration in either the primary or duplicate sample . James Riverkeeper location has no upstream site . Table 8 | PFAS Analytes with Greatest Concentration Increase in Downstream WWTP Site Samples State Waterbody Waterkeeper PFAS Analyte with Greatest Increase Amount of Increase (ppt) Total # of PFAS Analytes Elevated AL Cahaba River Cahaba Riverkeeper PFPeA 2 .7 6 Big Wills Creek Coosa Riverkeeper FOSA 1 .6 4 CA Santa Ana River [Nov .]Inland Empire Waterkeeper PFPeA 31 2 Los Angeles River LA Waterkeeper PFPeA 8 5 CT Naugatuck River Long Island Soundkeeper PFHxA 1 .8 7 FL East Canal Tampa Bay Waterkeeper No Upstream Sample GA Chattahoochee River Chattahoochee Riverkeeper PFTeA 4 .1 9 MD Monocacy River Potomac Riverkeeper PFPeA 17 .8 8 MI Rouge River Detroit Riverkeeper PFOA 40 .2 5 MS Pearl River Pearl Riverkeeper No Upstream Sample NC Cape Fear River Cape Fear Riverkeeper PFOS 2 9 Haw River Haw Riverkeeper PFPeA 22 14 NJ Ramapo River [Nov .]Hackensack Riverkeeper PFHxS 3 .5 5 OR Tualatin River Tualatin Riverkeepers PFHxA 7 .1 9 RI Pawtuxet River ©Narragansett Bay Riverkeeper PFPeA 0 .2 4 SC Pocotaligo River Black-Sampit Riverkeeper PFHxA 39 .4 13 TX Hunting Bayou Bayou City Waterkeeper PFHxA 4 .2 7 VA Appomattox River James Riverkeeper PFPeA 0 .9 5 WA Spokane River Spokane Riverkeeper PFHxA 1 .46 4 WI Root River ©Milwaukee Riverkeeper PFPeA 12 .3 10 WV Opequon Creek Upper Potomac Riverkeeper PFPeA 1 .4 4 Ohio River West Virginia Headwaters Waterkeeper PFBS 0 .1 1 © Combined: The result represents the highest concentration in either the primary or duplicate sample . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 3130 Similarly, near biosolids land application sites, as shown in Figure 10 (above), the most frequently detected PFAS include PFOA, PFBA, PFHxA, PFOS, PFHpA, PFBS, and PFHxS, occurring in 19 or more samples . In 16 samples, the sampling detected PFOA, PFBA, PFHxA, PFOS, PFHpA, PFBS, and PFHxS (often as well as other PFAS) at that sin- gle location . See Appendix A. By contrast, PFUnA, PFDoA, PFTeA, 8:2 FTS, NMeFOSAA, NEtFOSAA, HFPO-DA (Gen-X), PFMBA, and PFMPA were detected at 3 or fewer sampling sites near WWTPs, and PFDA, PFPeS, PFHpS, and HFPO-DA (Gen-X) were detected in 3 or fewer samples near biosolids land application sites . Additionally, as shown in Tables 10 (p. 34) and Table 11 (p. 36), as a result of the presence of multiple PFAS chemicals, the total PFAS concentration down- stream from 17 WWTPs and six biosolids land application sites increased, sometimes very significantly, above total upstream PFAS concentrations . Significant total PFAS con- centrations were also detected at the downstream sites for two WWTPs and one biosolids land application field that did not have upstream sampling sites . Figure 10 | PFAS Types Detected Upstream and Downstream from Biosolids Land Application Fields NUMBER OF DETECTIONS PFOA PFBA PFHxA PFOS PFHpA PFBS PFHxS PFPeA PFNA FOSA PFDA HFPO-DA (GenX) PFPeS PFHpS — — — — — — — — — — — — — — — 21 20 20 20 19 19 19 11 8 4 3 3 1 1 5 10 15 20 25PFAS TYPEFigure 9 | PFAS Types Detected Upstream and Downstream from WWTPs NUMBER OF DETECTIONS PFOS PFHxA PFOA PFHxS PFBS PFPeA PFHpA PFBA PFNA PFDA PFPeS 6:2 FTS FOSA PFUnA HFPO-DA (GenX) PFMPA PFDoA 8:2 FTS NMeFOSAA NEtFOSAA PFTeA PFMBA 48 47 46 45 44 43 43 42 34 13 13 5 5 3 3 3 2 2 2 2 1 1 5 10 15 20 25 30 35 40 45 50PFAS TYPEWATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 3332 As shown in Table 10 (p. 34) and Figure 11 (above), at WWTPs: MICHIGAN The Rouge River's total PFAS concentration increased from 33 .71 ppt upstream to 83 .20 ppt downstream from the GLWA WRRF — an increase of 49 .49 ppt or 146 .81% . OREGON The Tualatin River's total PFAS concentration increased from 0 .97 ppt upstream to 30 .02 ppt immediately downstream from the Rock Creek WRRF — an increase of 29 .05 ppt or 2,994 .85% . SOUTH CAROLINA The Pocotaligo River's total PFAS concentration increased from 110 .38 ppt upstream to 228 .39 ppt downstream from the Sumter Pocotalio River Plant—an increase of 118 .01 ppt or 106 .91% . NORTH CAROLINA The Haw River's total PFAS concentration increased from 78 .07 ppt upstream to 144 .54 ppt down- stream from the Graham WWTP —an increase of 66 .47 ppt or 85 .14% . Figure 11 | Amount of Total PFAS Increase Downstream from WWTPs PFAS CONCENTRATION INCREASE (ppt) Pocotaligo River | SC Haw River | NC Rouge River | MI Monocacy River | MD Tualatin River | OR Santa Ana River | CA Root River | WI Chattahoochee River | GA Ramapo River | NJ Los Angeles River | CA Cape Fear River | NC Hunting Bayou | TX Naugatuck River | CT Spokane River | WA Cahaba River | AL Opequon Creek | WV Appomattox River | VA 118.01 66.47 49.49 33.64 29.05 27.43 [Nov.] 26.59 © 15.58 10.10 [Nov.] 6.01 5.81 5.70 4.90 4.76 3.46 1.80 0.50 10 20 30 40 50 60 70 80 90 100 110 120SAMPLING SITETable 10 | Total PFAS Concentrations Upstream and Downstream from WWTPs State Waterbody Waterkeeper Total PFAS (ppt)Increase or Decrease (ppt) Percent Increase or DecreaseUpstreamDownstream AL Cahaba River Cahaba Riverkeeper 38 .07 41 .53 3 .46 9 .09% Big Wills Creek Coosa Riverkeeper 15 .04 12 .71 -2 .33 -15 .49% CA Santa Ana River [Nov .]Inland Empire Waterkeeper 89 .70 117 .13 27 .43 30 .58% Los Angeles River LA Waterkeeper 69 .79 75 .80 6 .01 8 .61% CT Naugatuck River Long Island Soundkeeper 41 .60 46 .50 4 .90 11 .78% FL East Canal Tampa Bay Waterkeeper No Sample 58 .91 GA Chattahoochee River Chattahoochee Riverkeeper 17 .52 33 .10 15 .58 88 .93% MD Monocacy River Potomac Riverkeeper 26 .28 59 .92 33 .64 128 .01% MI Rouge River Detroit Riverkeeper 33 .71 83 .20 49 .49 146 .81% MS Pearl River Pearl Riverkeeper No Sample 20 .71 NC Haw River Haw Riverkeeper 78 .07 144 .54 66 .47 85 .14% Cape Fear River Cape Fear Riverkeeper 51 .93 57 .74 5 .81 11 .19% NY/NJ Ramapo River [Nov .]Hackensack Riverkeeper 22 .10 32 .20 10 .10 45 .70% OR Tualatin River Tualatin Riverkeepers 0 .97 30 .02 29 .05 2994 .85% RI Pawtuxet River ©Narragansett Bay Riverkeeper 39 .40 39 .00 -0 .40 -1 .02% SC Pocotaligo River Black-Sampit Riverkeeper 110 .38 228 .39 118 .01 106 .91% TX Hunting Bayou Bayou City Waterkeeper 57 .77 63 .47 5 .70 9 .87% VA Appomattox River James Riverkeeper 21 .11 21 .61 0 .50 2 .37% WA Spokane River Spokane Riverkeeper 1 .24 6 .00 4 .76 383 .87% WI Root River ©Milwaukee Riverkeeper 29 .44 56 .03 26 .59 90 .32% WV Opequon Creek Upper Potomac Riverkeeper 45 .10 46 .90 1 .80 3 .99% Ohio River West Virginia Headwaters Waterkeeper 21 .95 18 .86 -3 .09 -14 .08% © Combined: The result represents the highest concentration in either the primary or duplicate sample . ©Combined: The result represents the highest concentration in either the primary or duplicate sample. WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 3534 As shown in Figure 13 [WWTP] and Figure 14 [Biosolids] (p. 38): The total downstream PFAS con- centrations exceeded EWG’s health-based guideline for total PFAS of 1 ppt at all 22 WWTP sites and at 9 of 10 biosolids land application sites .72 As shown in Table 11 and Figure 12 (above), downstream from biosolids land application sites: ALABAMA Cane Creek’s total PFAS concen- tration increased from 15 .04 ppt upstream to 43 .18 ppt down- stream from Jefferson County Commission WWTPs’ biosolids application site — an increase of 28 .14 ppt or 187 .10% . NORTH CAROLINA South River’s total PFAS concen- tration increased from 20 .99 ppt upstream to 41 .9 ppt downstream from Fayetteville Cross Creek WRF’s biosolids application fields — an increase of 20 .91 ppt or 99 .62% . WASHINGTON Dragoon Creek’s total PFAS con- centration increased from 0 .63 ppt upstream to 32 .89 ppt immedi- ately downstream from Spokane Riverside Park WRF’s biosolids land application fields —an increase of 32 .26 ppt or 5,120 .63% . Figure 13 | Total PFAS Concentrations Upstream and Downstream from WWTPs PFAS CONCENTRATION (ppt) 25 50 75 100 125 150 175 200 225 250SAMPLING SITEPocotaligo River | SC Haw River | NC Santa Ana River | CA Rouge River | MI Los Angeles River | CA Hunting Bayou | TX Monocacy River | MD Cape Fear River | NC Root River | WI Opequon Creek | WV Naugatuck River | CT Cahaba River | AL Pawtuxet River | RI Chattahoochee River | GA Ramapo River | NY/NJ Tualatin River | OR Appomattox River | VA Ohio River | WV Big Wills Creek | AL Spokane River | WA Pearl River | MS East Canal | FL 110.38 78.07 89.70 [Nov.] 33.71 69.79 57.77 26.28 51.93 29.44 © 45.10 41.60 38.07 39.40 © 17.52 22.10 [Nov.] 0.97 21.11 21.95 15.04 1.24 No Upstream Sample No Upstream Sample 228.39 144.54 117.13 [Nov.] 83.20 75.80 63.47 59.92 57.74 56.03 © 46.90 46.50 41.53 39.00 © 33.10 32.20 [Nov.] 30.02 21.61 18.86 12.71 6.00 20.71 58.91 Table 11 | Total PFAS Concentrations Upstream and Downstream from Biosolids Land Application Fields State Waterbody Waterkeeper Total PFAS (ppt)Increase or Decrease (ppt) Percent Increase or DecreaseUpstreamDownstream AL Cane Creek ©Cahaba Riverkeeper 15 .04 43 .18 28 .14 187 .10% Whippoorwill Creek Coosa Riverkeeper 14 .02 2 .27 -11 .75 -83 .81% MD Monocacy River Potomac Riverkeeper 27 .27 28 .02 0 .75 2 .75% MS Pearl River Pearl Riverkeeper 32 .67 30 .78 -1 .89 -5 .79% NC South River ©Cape Fear Riverkeeper 20 .99 41 .90 20 .91 99 .62% Haw Creek Haw Riverkeeper 102 .60 106 .51 3 .91 3 .81% VA Old Town Creek James Riverkeeper No Sample 15 .31 WA Dragoon Creek Spokane Riverkeeper 0 .63 32 .89 32 .26 5120 .63% WI Spring Creek Milwaukee Riverkeeper 1 .10 0 -1 .10 -100 .00% WV Back Creek ©Upper Potomac Riverkeeper 15 .26 17 .60 2 .34 15 .33% © Combined: The result represents the highest concentration in either the primary or duplicate sample . Figure 12 | Amount of Total PFAS Increase Downstream from Biosolids Land Application Fields PFAS CONCENTRATION INCREASE (ppt) Dragoon Creek | WA Cane Creek | AL South River | NC Old Town Creek | VA Haw Creek | NC Back Creek | WV Monocacy River | MD 5 10 15 20 25 30 35SAMPLING SITE32.26 28.14 20.91 15.31 3.91 2.34 0.75 Upstream (ppt) Downstream (ppt) EWG Total PFAS Health-Based Criteria (1 ppt) ©Combined: The result represents the highest concentration in either the primary or duplicate sample. WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 3736 Table 12 | State, Federal, and EWG PFAS Criteria Applicable to Sampled Watersheds77 PFAS Analyte Value (ppt)Source 78 Type Note79 PFBA 1000 EWG Health Guideline 1800 CT DW Action Level PFPeA 1000 EWG Health Guideline 70 RI SW Quality Action Level => Sum of 8 PFAS PFHxA 1000 EWG Health Guideline 240 CT DW Action Level 400,000 MI MCL 70 RI SW Quality Action Level => Sum of 8 PFAS PFHpA 1000 EWG Health Guideline 70 RI SW Quality Action Level => Sum of 8 PFAS PFOA 0 .09 EWG Health Guideline 4 EPA MCL 0 .0009 EPA SW HH Water + Organism 0 .007 CA Public Health Goal 16 CT DW Action Level 500 FL HH SW Screening Level 8 MI MCL 66 MI SW Noncancer (DW) 10 NY MCL 6 .7 NY Ambient WQ for HH (DW) 30 OR DW Health Advisory Level => Sum of 4 PFAS 70 RI SW Quality Action Level => Sum of 8 PFAS 20 RI MCL 10 WA DW Action Level 70 WI MCL Alone or +PFOS 20 WI SW Quality (DW) PFNA 0 .006 EWG Health Guideline 10 EPA MCL n/a EPA Hazard Index of 1 (unitless)PFHxS, PFNA, HFPO-DA, and PFBS 12 CT DW Action Level 6 MI MCL 30 OR DW Health Advisory Level => Sum of 4 PFAS 70 RI SW Quality Action Level => Sum of 8 PFAS 9 WA DW Action Level PFDA 0 .006 EWG Health Guideline 70 RI SW Quality Action Level => Sum of 8 PFAS PFUnA 0 .006 EWG Health Guideline PFDoA 0 .006 EWG Health Guideline PFTrDA 0 .006 EWG Health Guideline PFTeA 0 .006 EWG Health Guideline PFAS Criteria While there is no safe level of PFAS in drinking water, there are a limited number of state and/or federal health- based criteria applicable to water for some PFAS . EWG has developed health-based criteria applicable to water for most PFAS73 that can also be utilized to evaluate the levels of PFAS we detected in this sampling project . See Ta ble 12 (p. 39). EPA has finalized MCLs under the federal SDWA74 for only five PFAS—PFOA, PFOS, PFNA, PFHxS, and HFPO-DA (Gen-X)—and a Hazard Index for mixtures containing two or more of PFHxS, PFNA, HFPO-DA, and PFBS .75 EPA has also published draft HHWQC under the Clean Water Act for PFOA, PFOS, and PFBS that apply to surface waters and “reflect the latest available scientific information including final human health toxicity values, draft bioaccumulation factors, draft relative source contributions, and updated drinking water ingestion rates .”76 Additionally, some states have adopted criteria for certain types of PFAS in surface waters . See Ta ble 12 (p. 39). The sampling data we collected detected elevated PFAS concentrations downstream from the WWTPs and biosolids land application sites that often exceeded SDWA MCLs for PFOA, PFOS, and/or PFHxS, and draft HHWQC (Water + Organism) for PFOA and PFOS and/ or EWG’s guidelines for multiple PFAS . See Tables 13 –15 (pp. 42 – 44). Haw Creek | NC Cane Creek | AL South River | NC Dragoon Creek | WA Pearl River | MS Monocacy River | MD Back Creek | WV Old Town Creek | VA Whippoorwill Creek | AL Spring Creek | WI Figure 14 | Total PFAS Upstream and Downstream from Biosolids Application Sites PFAS CONCENTRATION (ppt) 10 20 30 40 50 60 70 80 90 100 110 120 102.6 15.04 © 20.99 0.63 32.67 27.27 15.26 © n/a 14.02 1.1 106.51 43.18 © 41.9 © 32.89 30.78 28.02 17.6 © 15.31 2.27 0SAMPLING SITEUpstream (ppt) Downstream (ppt) EWG Total PFAS Health-Based Criteria (1 ppt) ©Combined: The result represents the highest concentration in either the primary or duplicate sample. WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 3938 Table 12 | State, Federal, and EWG PFAS Criteria Applicable to Sampled Watersheds77 PFAS Analyte Value (ppt)Source 78 Type Note79 PFNS 1 EWG Health Guideline PFDS 0 .001 EWG Health Guideline PFDoS 1 EWG Health Guideline FOSA 0 .3 EWG Health Guideline NMeFOSAA 1 EWG Health Guideline NEtFOSAA 1 EWG Health Guideline 4:2 FTS 1 EWG Health Guideline 6:2 FTS 1 EWG Health Guideline 8:2 FTS 1 EWG Health Guideline NEtFOSA 1 EWG Health Guideline NMeFOSA 1 EWG Health Guideline NMeFOSE 1 EWG Health Guideline NEtFOSE 1 EWG Health Guideline 9Cl-PF3ONS 1 EWG Health Guideline 2 CT DW Action Level GenX 9 EWG Health Guideline 10 EPA MCL n/a EPA Hazard Index of 1 (unitless)PFHxS, PFNA, HFPO-DA, and PFBS 19 CT DW Action Level 370 MI MCL 11Cl-PF3OUdS 1 EWG Health Guideline 5 CT DW Action Level ADONA 1 EWG Health Guideline 3:3 FTCA 5:3 FTCA 7:3 FTCA NFDHA PFMBA 1 EWG Health Guideline PFMPA 1 EWG Health Guideline PFEESA EWG Health Guideline Table 12 | State, Federal, and EWG PFAS Criteria Applicable to Sampled Watersheds77 PFAS Analyte Value (ppt)Source 78 Type Note79 PFBS 2000 EWG Health Guideline n/a EPA Hazard Index of 1 (unitless)PFHxS, PFNA, HFPO-DA, and PFBS 400 EPA SW HH Water + Organism 500 CA Health Notification Level 760 CT DW Action Level 420 MI MCL 345 WA DW Action Level PFPeS 1 EWG Health Guideline PFHxS 0 .001 EWG Health Guideline 10 EPA MCL n/a EPA Hazard Index of 1 (unitless)PFHxS, PFNA, HFPO-DA, and PFBS 3 CA Health Notification Level 49 CT DW Action Level 140 MD DW Health Advisory Level 51 MI MCL 59 MI SW Noncancer (DW) 30 OR DW Health Advisory Level => Sum of 4 PFAS 1 RI SW Quality Action Level => Sum of 8 PFAS 20 RI MCL 65 WA DW Action Level PFHpS 0 .001 EWG Health Guideline PFOS 0 .3 EWG Health Guideline 4 EPA MCL 0 .06 EPA SW HH Water + Organism 1 CA Public Health Goal 10 CT DW Action Level 10 FL HH SW Screening Level 16 MI MCL 11 MI SW Noncancer (DW) 10 NY MCL 2 .7 NY Ambient WQ for HH (DW) 30 OR DW Level => Sum of 4 PFAS 70 RI SW Quality Action Level => Sum of 8 PFAS 20 RI MCL 15 WA DW Action Level 70 WI MCL Alone or +PFOS 8 WI SW Quality (All Waters) WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 4140 Samples upstream from WWTPs and biosolids land appli- cation fields also frequently exceeded these criteria . For example, the concentration of PFOS (11 ppt) and PFHxS (15 ppt) exceeded the MCL upstream from the Riverside RWQCP in the Santa Ana River (CA) [Nov .] and the con- centration of PFOA (32 ppt) and PFOS (36 ppt) exceeded the MCL upstream from the Graham WWTP biosolids land application site in Haw Creek (NC) . See Appendix A. However, except where otherwise noted, the evaluation in Table 13 (above) and Table 14 (p. 43) only assesses downstream results where the downstream concentration exceeded the upstream concentration . These results are particularly concerning given the fact that the values are equilibrium concentrations that are more reflective of bio- availability, toxicity, and risk . Table 14 | Exceedances of EPA HHWQC (Water + Organism) in Elevated Samples Downstream from WWTP and Biosolids Sites State Waterbody Waterkeeper PFOA Amounts (ppt)PFOS Amounts (ppt) Sample Results EPA Criteria Excess Amount Sample Results EPA Criteria Excess Amount Wastewater Treatment Sites AL Cahaba River Cahaba Riverkeeper 4 .90 0 .0009 4 .8991 Big Wills Creek Coosa Riverkeeper 2 .20 0 .0009 2 .1991 CA Santa Ana River [Aug .] Inland Empire Waterkeeper 13 .00 0 .0009 12 .9991 12 .00 0 .06 11 .94 CT Naugatuck River Long Island Soundkeeper 8 .30 0 .06 8 .24 FL East CanalTampa Bay Waterkeeper 7 .10 0 .0009 7 .0991 11 .00 0 .06 10 .94 GA Chattahoochee River Chattahoochee Riverkeeper 2 .80 0 .0009 2 .7991 MD Monocacy River Potomac Riverkeeper 6 .80 0 .0009 6 .7991 MI Rouge River Detroit Riverkeeper 44 .00 0 .0009 43 .9991 3 .10 0 .06 3 .04 MS Pearl RiverPearl Riverkeeper 2 .90 0 .0009 2 .8991 3 .50 0 .06 3 .44 NC Cape Fear River Cape Fear Riverkeeper 8 .30 0 .0009 8 .2991 13 .00 0 .06 12 .94 Haw River Haw Riverkeeper 10 .00 0 .0009 9 .9991 23 .00 0 .06 22 .94 NJ Ramapo River [Nov .]Hackensack Riverkeeper 6 .70 0 .0009 6 .6991 4 .70 0 .06 4 .64 OR Tualatin River Tualatin Riverkeepers 3 .30 0 .0009 3 .2991 2 .50 0 .06 2 .44 SC Pocotaligo River Black-Sampit Riverkeeper 28 .00 0 .0009 27 .9991 30 .00 0 .06 29 .94 TX Hunting Bayou Bayou City Waterkeeper 4 .00 0 .0009 3 .9991 12 .00 0 .06 11 .94 VA Appomattox River James Riverkeeper 2 .60 0 .0009 2 .5991 2 .60 0 .06 2 .54 WA Spokane River Spokane Riverkeeper 1 .10 0 .0009 1 .0991 2 .10 0 .06 2 .04 WI Root River ©Milwaukee Riverkeeper 8 .00 0 .0009 7 .9991 5 .00 0 .06 4 .94 WV Opequon Creek Upper Potomac Riverkeeper 4 .10 0 .0009 4 .0991 Biosolids Application Sites AL Cane Creek ©Cahaba Riverkeeper/ Black Warrior Riverkeeper 4 .10 0 .0009 4 .0991 5 .80 0 .06 5 .74 MS Pearl River Pearl Riverkeeper 3 .60 0 .06 3 .54 NC South River ©Cape Fear Riverkeeper 5 .80 0 .0009 5 .7991 7 .50 0 .06 7 .44 VA Old Town CreekJames Riverkeeper 3 .90 0 .0009 3 .8991 3 .10 0 .06 3 .04 WA Dragoon Creek Spokane Riverkeeper 1 .50 0 .0009 1 .4991 Note: Only includes values that were elevated in comparison to upstream sites, except where as noted with an there was no upstream site . © Combined: The result represents the highest concentration in either the primary or duplicate sample . Table 13 | Exceedances of MCLs in Elevated Samples Downstream from WWTPs and Biosolids Land Application Sites State Waterbody Waterkeeper Analyte Amounts(ppt)EPA MCL PFOA PFOS PFHxS PFOA PFOS PFHxS Wastewater Treatment Sites AL Cahaba River Cahaba Riverkeeper 4 .90 4 4 10 CA Santa Ana River [Aug .] Inland Empire Waterkeeper 13 .00 12 .00 4 4 10 CT Naugatuck River Long Island Soundkeeper 8 .30 4 4 10 FL East Canal Tampa Bay Waterkeeper 7 .10 11 .00 4 4 10 MD Monocacy River Potomac Riverkeeper 6 .80 4 4 10 MI Rouge River Detroit Riverkeeper 44 .00 16 .00 4 4 10 NC Cape Fear River Cape Fear Riverkeeper 8 .30 13 .00 4 4 10 Haw River Haw Riverkeeper 10 .00 23 .00 4 4 10 NJ Ramapo River [Nov .]Hackensack Riverkeeper 6 .70 4 .70 4 4 10 SC Pocotaligo River Black-Sampit Riverkeeper 28 .00 30 .00 4 4 10 TX Hunting Bayou Bayou City Waterkeeper 4 .00 12 .00 4 4 10 WI Root River ©Milwaukee Riverkeeper 8 .00 5 .00 4 4 10 WV Opequon Creek Upper Potomac Riverkeeper 4 .10 4 4 10 Biosolids Application Sites AL Cane Creek © Cahaba Riverkeeper Black Warrior Riverkeeper 4 .10 5 .80 4 4 10 NC South River © Cape Fear Riverkeeper 5 .80 7 .50 4 4 10 Note: Only includes values that were elevated in comparison to upstream sites, except where as noted with an there was no upstream site . © Combined: The result represents the highest concentration in either the primary or duplicate sample . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 4342 As shown in Table 13 (p. 42) and Figure 15 [WWTPs] (p. 46): 1 . The MCL for PFOA was exceeded at 12 downstream WWTP sites and two downstream biosolids land application sites . In the Pocotaligo River downstream from the Sumter Pocotaligo River Plant in South Carolina, PFOA exceeded the MCL of 4 ppt by 24 ppt . In the Rouge River downstream from the GLWA WRRF in Michigan, PFOA exceeded the MCL of 4 ppt by 40 ppt . In the Santa Ana River [Aug .] downstream from the Riverside RWQCP in California, PFOA exceeded the MCL of 4 ppt by 9 ppt . 2 . The MCL for PFOS was exceeded at nine down- stream WWTP sites and two downstream biosolids land application sites . In the Pocotaligo River downstream from the Sumter Pocotaligo River Plant in South Carolina, PFOS exceeded the MCL of 4 ppt by 26 ppt . In the Haw River downstream from the Graham WWTP in North Carolina, PFOS exceeded the MCL of 4 ppt by 19 ppt . In the Cape Fear River downstream from the Fayetteville Cross Creek WRF, PFOS exceeded the MCL of 4 ppt by 9 ppt . 3 . The MCL for PFHxS was exceeded at one down- stream WWTP site . In the Rouge River downstream from the GLWA WRRF in Michigan, PFHxS exceeded the MCL of 10 ppt by 6 ppt . As shown in Table 14 (p. 43) and Figure 16 [WWTPs] (p. 47): 1 . The draft HHWQC (Water + Organism) for PFOA was exceeded at 18 downstream WWTP sites and 4 downstream biosolids land application sites . In the Pocotaligo River downstream from the Sumter Pocotaligo River Plant in South Carolina, PFOA exceeded the draft HHWQC of 0 .0009 ppt by 27 .9991 ppt . In the Rouge River downstream from the GLWA WRRF in Michigan, PFOA exceeded the draft HHWQC of 0 .0009 ppt by 43 .9991 ppt . In the South River downstream from Fayetteville Cross Creek’s biosolids land application fields in North Carolina, PFOA exceeded the draft HHWQC of 0 .0009 ppt by 5 .7991 ppt . 2 . The draft HHWQC (Water + Organism) for PFOS was exceeded at 14 downstream WWTP sites and 4 downstream biosolids land application sites . In the Pocotaligo River downstream from the Sumter Pocotaligo River Plant in South Carolina, PFOS exceeded the draft HHWQC of 0 .06 by 29 .94 ppt . In the Haw River downstream from the Graham WWTP in North Carolina, PFOS exceeded the draft HHWQC of 0 .06 by 22 .94 ppt . In the South River downstream from Fayetteville Cross Creek’s biosolids land application fields in North Carolina, PFOS exceeded the draft HHWQC of 0 .06 by 7 .44 ppt . Table 15 | Exceedances of EWG Criteria in Elevated Samples Downstream from WWTPs and Biosolids Land Application Sites State Waterbody Amounts by Analyte (ppt)PFOAPFOSPFHxSPFNAPFDAFOSAPFDoA6:2 FTSPFUnAPFTeAPFPeSNMeFOSAAPFMPAPFMBAPFHpSEWG Criteria Amount 0.09 0.3 0.001 0.006 0.006 0.3 0.006 1.00 0.006 0.006 1.00 1.00 1.00 1.00 0.001 Wastewater Treatment Sites AL Cahaba River 4.90 1.50 Big Wills Creek 2.20 0.64 1.60 CA Santa Ana River[Aug .] 13.00 12.00 2.10 6.10 Los Angeles River 2.10 CT Naugatuck River 8.30 1.70 FL East Canal 7.10 11.00 3.90 1.30 GA Chattahoochee River 2.80 1.20 4.10 2.10 MD Monocacy River 6.80 2.50 0.62 MI Rouge River 44.00 3.10 16.00 5.00 MS Pearl River 2.90 3.50 1.30 0.71 NC Haw River 10.00 23.00 4.50 2.20 2.60 0.59 1.10 0.87 Cape Fear River 8.30 13.00 5.30 NJ Ramapo River [Nov .]6.70 4.70 3.50 OR Tualatin River 3.30 2.50 0.73 0.59 RI Pawtuxet River ©2.30 2.10 SC Pocotaligo River 28.00 30.00 2.30 2.10 1.70 22.00 0.79 1.10 TX Hunting Bayou 4.00 12.00 1.30 0.64 VA Appomattox River 2.60 2.60 0.75 WA Spokane River 1.10 2.10 0.80 WI Root River ©8.00 5.00 2.10 1.30 0.83 WV Opequon Creek 4.10 Ohio River Biosolids Application Sites AL Cane Creek ©4.10 5.80 0.68 NC Haw Creek 1.90 0.81 2.20 1.30 South River ©5.80 7.50 2.40 1.40 0.86 MD Monocacy River 0.77 MS Pearl River 3.60 0.73 VA Old Town Creek 3.90 3.10 1.50 WA Dragoon Creek 1.50 0.71 0.88 Note: Only includes values that were elevated in comparison to upstream sites, except where as noted with an there was no upstream site . © Combined: The result represents the highest concentration in either the primary or duplicate sample . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 4544 EPA PFH xS MCL 28.00 10.00 44.00 6.80 13.00 [Aug.] 8.00 © 6.70 8.30 4.00 n/a 4.90 4.10 7.10 30.00 23.00 n/a n/a 12.00 [Aug.] 5.00 © 4.70 13.00 12.00 8.30 n/a n/a 11.00 Figure 15 | Exceedances of EPA PFAS MCLs Downstream from WWTP Outfalls Includes Only Sites Where Downstream PFAS Concentrations Exceeded Upstream PFAS Concentrations PFAS CONCENTRATION (ppt) Pocotaligo River | SC Haw River | NC Rouge River | MI Monocacy River | MD Santa Ana River | CA Root River | WI Ramapo River | NJ Cape Fear River | NC Hunting Bayou | TX Naugatuck River | CT Cahaba River | AL Opequon Creek | WV East Canal | FL 5 10 15 20 25 30 35 40 45 50SAMPLING SITEFigure 16 | Exceedances of Draft HHWQC (Water + Organism) Downstream from WWTPs Includes Only Sites Where Downstream Concentrations Exceeded Upstream PFAS Concentrations PFAS CONCENTRATION (ppt) Pocotaligo River | SC Haw River | NC Rouge River | MI Monocacy River | MD Tualatin River | OR Santa Ana River | CA Root River | WI Chattahoochee River | GA Ramapo River | NJ Cape Fear River | NC Hunting Bayou | TX Naugatuck River | CT Spokane River | WA Cahaba River | AL Opequon Creek | WV Appomatox River | VA Big Wills Creek | AL Pearl River | MS East Canal | FL 27.9991 9.9991 43.9991 6.7991 3.2991 12.9991 [Aug.] 7.9991 © 2.7991 6.6991 8.2991 3.9991 n/a 1.0991 4.8991 4.0991 2.5991 2.1991 2.8991 7.0991 5 10 15 20 25 30 35 40 45 50SAMPLING SITE29.94 22.94 3.04 n/a 2.44 11.94 [Aug.] 4.94 © n/a 4.64 12.94 11.94 8.24 2.04 n/a n/a n/a n/a 3.44 10.94 EPA PFOA & PFOS MCL n/a n/a 16.00 n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a PFOA PFOS PFHxS No upstream sample ©Combined: The result represents the highest concentration in either the primary or duplicate sample. PFOA PFOS No upstream sample ©Combined: The result represents the highest concentration in either the primary or duplicate sample. WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 4746 As shown in Table 15 (p. 44) and Figure 17 [WWTPs and Biosolids] (p. 49), EWG’s health-based criteria were exceeded at 29 locations downstream from WWTP sites and biosolids land application sites . The PFAS types that most frequently exceeded EWG’s criteria at the greatest number of elevated downstream sites were: • PFOA (22 sites) • PFOS (18 sites) • PFHxS (17 sites) • PFNA (14 sites) 1 . There are no federal standards for PFDA, which is a “[b]reakdown product of stain- and grease-proof coatings on food packaging, couches, carpets .”80 It was detected at higher concentrations in sampling sites downstream from six WWTPs and two biosolids land application fields at levels that exceed EWG’s health-based criteria . Based on “EPA’s toxicity value published in the Integrated Risk Information System’s toxicological review,” the EWG criteria for PFDA is 0 .006 ppt to protect against developmental and immune harm in humans .81 In the Rouge River downstream from the GLWA WRRF in Michigan, the PFDA concentration was 5 ppt . In the Haw River downstream from the Graham WWTP in North Carolina, the PFDA concentration was 2 .6 ppt . In the Los Angeles River downstream from the LA-Glendale WRP in California, the PFDA concen- tration was 2 .1 ppt . In Haw Creek downstream from the Graham WWTP biosolids land application field in North Carolina, the PFDA concentration was 0 .81 ppt . 2 . There are no federal standards for FOSA, which is widely used in industrial processes .82 It was detected at higher concentrations in sampling sites down- stream from three WWTPs and two biosolids land application fields at levels that exceed EWG’s health- based criteria . Based on “EPA’s final toxicity value for PFOS from the Office of Water’s Final Human Health Toxicity Assessment,” the EWG criteria for FOSA is 0 .3 ppt to protect against cardiovascular harm and harm to fetal growth in humans .83 In the Pocotaligo River downstream from the Sumter Pocotaligo River Plant in South Carolina, the FOSA concentration was 1 .7 ppt . In Big Wills Creek downstream from the Rainbow City WWTP in Alabama, the FOSA concentration was 1 .6 ppt . In the Monocacy River downstream from the City of Frederick WWTP in Maryland, the FOSA concen- tration was 0 .62 ppt . In Dragoon Creek downstream from the Spokane Riverside Park WRF’s biosolids land application fields in Washington, the FOSA concentration was 0 .88 ppt . In the South River downstream from Fayetteville Cross Creek’s biosolids land application fields in North Carolina, the FOSA concentration was 0 .86 ppt . Figure 17 | Number of Elevated Downstream Samples Exceeding EWG Criteria Downstream from Wastewater Treatment Plants and Biosolids Land Application Sites NUMBER OF SAMPLES EXCEEDING CRITERIA PFOA PFOS PFHxS PFNA PFDA FOSA PFDoA PFUnA 6:2 FTS PFPeS PFTeA NMeFOSAA PFMPA PFMBA PFHpS 2 4 6 8 10 12 14 16 18 20 22PFAS ANALYTE22 18 17 14 8 5 2 2 2 2 1 1 1 1 1 Note: Santa Ana, CA [Aug .] and East Canal, FL did not obtain upstream samples . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 4948 3 . There are no federal standards for 6:2 FTS, which is used as a replacement for PFOS in aqueous film-forming foam and in the chromium electroplat- ing industry .84 It was detected at higher concentra- tions in sampling sites downstream from two WWTPs at levels that exceed EWG’s health-based criteria . “[B]ased on studies by Phillipe Grandjean of Harvard University and many other independent research- ers,” the EWG criteria for 6:2 FTS is 1 ppt to protect against adverse human health effects .85 In the Pocotaligo River downstream from the Sumter Pocotaligo River Plant in South Carolina, the 6:2 FTS concentration was 22 ppt .86 In the Haw River downstream from the Graham WWTP in North Carolina, the 6:2 FTS concentra- tion was 1 .1 ppt . 4 . There are no federal standards for PFTeA, which is used in a wide variety of consumer products .87 It was detected at higher concentrations in sampling sites downstream from one WWTP at levels that exceed EWG’s health-based criteria . “[B]ased on EPA’s recommended application of the toxicity value for PFDA published in the Integrated Risk Information System’s toxicological review,” the EWG criteria for PFTeA is 0 .006 ppt to protect against harm to the immune system and harm to fetal growth and child development .88 In the Chattahoochee River downstream from the City of Atlanta’s R .M . Clayton WRC, Cobb County’s R .L . Sutton WRF, and the West Area WQCF in Georgia, the PFTeA concentration was 4 .1 ppt . 5 . There are no federal standards for PFHpS, which is used in many consumer products . It was detected at higher concentrations in sampling sites downstream from one biosolids land application site at levels that exceed EWG’s health-based criteria . Based on “EPA’s recommended application of the PFHxS toxicity value published in the Integrated Risk Information System’s toxicological review,” the EWG criteria for PFHpS is 0 .001 ppt to protect against cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes .89 In Haw Creek downstream from the Graham WWTP biosolids land application field in North Carolina, the PFHpS concentration was 1 .3 ppt . 6 . There are no federal standards for PFMBA, which is used in many consumer products . It was detected at higher concentrations in sampling sites down- stream from one WWTP at levels that exceed EWG’s health-based criteria . “[B]ased on studies by Phillipe Grandjean of Harvard University and many other independent researchers,” the EWG criteria for PFMBA is 1 ppt to protect against adverse human health effects .90 In the Santa Ana River [Aug .] downstream from the Riverside RWQCP in California, the concentration of PFMBA was 6 .1 ppt . EVALUATION OF FACILITIES AND WATERSHEDS To further evaluate the contribution of PFAS to the sam- pled watersheds, we conducted a comparative analysis of upstream and downstream results for each of the WWTPs and biosolids land application fields, and we assessed the results in relation to the available criteria for evaluating human health risks . Additionally, we reviewed information about the facilities from publicly available sources and EJScreen data to better understand the potential sources and environmental justice implications of PFAS contami- nation . This information was obtained from state agencies, EPA, the facilities’ webpages, public information requests, and other online resources . Statements made herein about the facilities and industrial users rely on the accuracy and completeness of these sources . While we undertook a thorough review of available, but often limited informa- tion, we make no independent representation of these facts . The results of our evaluation are set forth below . EPA EJScreen Enforcement and Compliance History Online (ECHO) and Community Reports discussed for each facility can be found in Appendix B . Nearly all of the WWTPs evaluated in this project accept discharges into their treatment systems from industrial users . Yet, based on our review of public records, it appears the overwhelming majority of the WWTPs do not place any PFAS limits on these users . This is con- cerning given the fact that a significant number of these industrial users operate in sectors known for producing and/or utilizing PFAS . Based on information taken from EPA’s PFAS Analytic Tools, which is a publicly available online repository of PFAS data collected by the agency, we determined that most WWTPs are likely receiving discharges from at least one permitted industrial user that is “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemicals .” Frequently, the data indicates that there may be additional unpermitted industrial users of these systems that have been identified in the database . To effectively stem the tide of PFAS contamination in U .S . waterways, federal and state governments must prior- itize regulation of the industrial sources from which it orig- inates . Industry, which profits from the use of these toxic chemicals, must also be required to share the financial bur- den of cleaning up its PFAS pollution . Otherwise, WWTPs, and the communities that rely on them, will be forced to shoulder that burden alone . This is not only a matter of fairness; it also makes financial sense given that controlling PFAS at the source is significantly less costly than trying to remove it at the wastewater or drinking water utility level .91 EPA’s own investigations have confirmed both the extent of PFAS contamination in industrial wastewater and the need for pretreatment solutions to sufficiently address the problem . In 2021, EPA studied industrial discharges of PFAS from five industrial categories, including: Organic Chemicals, Plastics, and Synthetic Fibers Manufacturing; Metal Finishing; Pulp, Paper and Paperboard Manufacturing; Textile Mills; and Commercial Airports . The Agency found that “[f]ew facilities in these industries cur- rently have monitoring requirements, effluent limitations, or pretreatment standards for PFAS in their wastewater discharge permits .”92 It then “identified available wastewa- ter treatment technologies, such as activated carbon, ion exchange, and membrane filtration, that may reduce PFAS in wastewater discharges from facilities in these industrial point source categories .”93 Pretreatment technologies such as these currently exist and have been found to be both cost-effective and successful in reducing concentrations of PFOA and PFOS .94 Given the apparent extent of industry’s contribution to PFAS pollution in WWTPs, it is imperative that federal and state governments incorporate pretreat- ment technologies into their strategies to protect public health in their communities . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 5150 Black-Sampit Riverkeeper, Pocotaligo River, South Carolina Wastewater Treatment Plant Site According to its 2017 NPDES permit application, the Sumter Pocotaligo River WWTP is a municipal waste- water treatment system that is owned and operated by the City of Sumter’s Wastewater Division of the Utilities Department and serves 51,000 people . In addition, the facility handles wastewater from numerous industrial dischargers, including four permitted Significant Industrial Users and 20 permitted Categorical Industrial Users . The WWTP discharges treated wastewater into the East Branch of the Pocotaligo River at an average design flow of 15 MGD . The Pocotaligo River Watershed makes up 171,780 acres of the Upper Coastal Plain region of South Carolina . According to ECHO, Sumter is located in an area with four State EJ Indexes and six Federal EJ Indexes greater than the state’s 80th percentile within one mile of the facility, including wastewater discharges at 87 (State) .95 According to the EPA EJScreen, of people living within one mile of Sumter WWTP, 65% are people of color and 42% are low income .96 The NPDES permit for Sumter WWTP does not include any limits on the amount of PFAS the facility discharges into the Pocotaligo River and there are no pretreatment limits to control PFAS discharges to the WWTP by indus- trial dischargers . Of the 24 permitted industrial users discharging wastewater to Sumter Pocotaligo River WWTP, EPA’s PFAS Analytic Tools97 lists the following 11 as facil- ities “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemicals”: • Apex Tools (Metal Coating) • Armoloy Southeast (Metal Coating) • Continental Tire (Consumer Products) • EMS — chemie (Plastics and Resins) • Enersys — Sumter Metals (Metal Machinery Mfg .) • GRR (Waste Management) • Interlake Mecalux (Metal Machinery Mfg .) • Metal Finishing Services, Inc . (Metal Coating) • Metokote Corporation (Metal Coating) • Phibro — Tech, Inc . (Chemical Mfg .) • Santee Print Works (Textiles and Leather) There are likely additional unpermitted industrial discharg- ers contributing PFAS to the WWTP given that EPA’s PFAS Analytic Tools identifies 40 facilities located within the City of Sumter that operate in PFAS-related sectors, including: • Airports • Chemical Mfg . • Consumer Products • Electronics Industry • Glass Products • Metal Coating • Metal Machinery Mfg . • National Defense • Paints and Coatings • Plastics and Resins • Textiles and Leathers • Waste Management WATERSHEDS WITH THE GREATEST DOWNSTREAM TOTAL PFAS CONCENTRATION INCREASES We generated more detailed evaluations for watersheds where the WWTPs and biosolids land application fields had the greatest increases in total PFAS concentrations between upstream and downstream sampling sites . These evaluations are presented below by Waterkeeper group watershed . From 2022 to 2023, as part of the state’s Ambient Surface Water PFAS Project,98 the South Carolina Department of Environmental Services tested for a series of 26 PFAS or precursor compounds in ambient sur- face water at locations upstream and downstream from Sumter Pocotaligo River WWTP’s outfall . The results show significant increases in the average concentrations of multiple types of PFAS between the upstream monitoring location and the closest downstream monitoring loca- tion, for example: • PFOS (12 .1 ppt to 62 .93 ppt) • PFHxA (5 .69 ppt to 84 .67 ppt) • PFPeA (5 .29 ppt to 69 .03 ppt) • 6:2 FTS (N .D . to 53 .95 ppt) Sampling conducted by Black-Sampit Riverkeeper in December 2023 also detected significant increases in PFAS downstream from the Sumter Pocotaligo River WWTP’s outfall, particularly PFPeA (<1 ppt to 110 .9 ppt) and PFHxA (2 ppt to 194 .7 ppt) . For Phase II, Black-Sampit Riverkeeper deployed PFASsive™ passive sampling devices upstream and downstream from the WWTP's outfall to the East Branch of the Pocotaligo River from August 23, 2024 to September 25, 2024 . Both upstream and downstream sampling sites detected multiple types of regulated and unregulated PFAS .99 However, the concentrations of multiple types of PFAS increased significantly at the downstream site, resulting in a total PFAS concentra- tion of 228 .39 ppt . With an increase of 118 .01 ppt (106 .91%), this site became the most contaminated location detected in this moni- toring project . For example, the concentration of PFHxA increased from 9 .6 ppt to 49 ppt (410 .42%), the concen- tration of PFPeA increased from 9 .7 ppt to 38 ppt (291 .75%), and the concentration of PFHpA increased from 4 ppt to 21 ppt (425%) . Multiple other types of PFAS increased in downstream samples at levels ranging from 21 .74% to 144 .9%, including 6:2 FTS, which increased from non-detect to 22 ppt . These results are consistent with the findings of previous sampling, and indicate that the Sumter Pocotaligo River WWTP’s outfall is likely a significant source of PFAS in the Pocotaligo River . Downstream concentrations of PFAS demonstrate that the surface water at this location is unsafe for drinking without advanced treatment . For example, the concen- tration of PFOA at the downstream location was 28 ppt, which is 24 ppt greater than the MCL of 4 ppt, and the concentration of PFOS was 30 ppt, which is 26 ppt greater than the MCL of 4 ppt . The concentrations of PFOA and PFOS in the down- stream samples were also greater than the draft HHWQC (Water + Organism) . Specifically, PFOA exceeded the criteria of 0 .0009 ppt by 27 .9991 ppt, and PFOS exceeded the 0 .06 criteria by 29 .94 ppt . Sumter Pocotaligo WWTP | Pocotaligo River PFAS Phase II Sampling Site WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 5352 There are no national or state Clean Water Act ambi- ent surface water quality criteria for most PFAS detected at elevated levels, such as PFHxA, PFPeA, 6:2 FTS, PFHpA, PFBA, FOSA, PFNA, and PFUnA . However, sev- eral PFAS without federal or state standards, including PFDA, PFUnA, PFPeS, 6:2 FTS, FOSA, and NMeFOSAA, exceeded EWG’s health-based criteria, as did PFNA . See Ta ble 16 (above). This evaluation indicates that Sumter Pocotaligo River WWTP is contributing a significant amount of PFAS to the Pocotaligo River and that multiple industrial dischargers are likely contributing to the WWTP’s discharge of PFAS to the river . This pollution will likely continue to pose signif- icant risks to human health until pretreatment limits are imposed on industrial sources discharging into the WWTP, and a PFAS limit is included in the Sumter Pocotaligo River WWTP’s NPDES permit . Implementing these measures will require the installation of advanced treatment technology and a plan to safely manage the contaminants removed during treatment . Table 16 | Pocotaligo River Upstream and Downstream from Sumter WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFHxA 9.60 49.00 39.40 410.42%1000 PFPeA 9.70 38.00 28.30 291.75%1000 6:2 FTS 0.00 22.00 22.00 n/a 1 21.000 PFHpA 4.00 21.00 17.00 425.00%1000 PFOS 22.00 30.00 8.00 36.36%4 26.00 0.06 29.94 0.3 29.700 PFBA 4.90 12.00 7.10 144.90%1000 PFOA 23.00 28.00 5.00 21.74%4 24.00 0.0009 27.9991 0.09 27.910 PFBS 3.10 5.50 2.40 77.42%400 2000 PFDA 0.00 2.10 2.10 n/a 0.006 2.094 FOSA 0.00 1.70 1.70 n/a 0.3 1.400 PFNA 1.50 2.30 0.80 53.33%10 0.006 2.294 PFUnA 0.00 0.79 0.79 n/a 0.006 0.784 NMeFOSAA 0.66 1.10 0.44 66.67%1 0.100 PFPeS 1.20 1.10 -0.10 -8.33%1 0.100 NEtFOSAA 0.72 0.00 -0.72 -100.00%1 PFHxS 14.00 6.60 -7.40 -52.86%10 0.001 6.599 HFPO-DA (GenX)16.00 7.20 -8.80 -55.00%10 9 Total PFAS 110.38 228.39 118.01 106.91% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Haw Riverkeeper, Haw River and Haw Creek, North Carolina Wastewater Treatment Plant and Biosolids Sites The Graham WWTP is a municipal wastewater treatment system that is owned and operated by the City of Graham that serves a population of close to 17,000 residents .100 In addition, the facility handles wastewater from multiple industrial dischargers, including five permitted Significant Industrial Users, of which three are categorical . The WWTP discharges treated wastewater into the Haw River at an average design flow of 3 .5 MGD . The Haw River, which flows 110 miles south to the Cape Fear River and joins the Jordan Lake Reservoir, spans a 1,700-square-mile water- shed . The Haw River and its watershed provide drinking water to nearly one million people and supports diverse wildlife, including the endangered Cape Fear shiner . According to ECHO, Graham WWTP is located in an area with eight State Supplemental EJ Indexes and seven Federal Supplemental EJ Indexes greater than the 80th percentile within one mile of the facility, includ- ing wastewater discharges at 97 (State) .101 According to the EPA EJScreen, of people living within one mile of Graham WWTP, 35% are people of color and 27% are low income .102 Although Graham WWTP’s NPDES permit103 requires that the facility monitor for PFAS chemicals listed in Table 1 of EPA Method 1633 twice a year, the permit does not include any limits on the amount of PFAS the facility discharges . EPA’s PFAS Analytic Tools104 identifies seven facilities in the City of Graham that are “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemicals .” Specifically, those industry sectors include Chemical Mfg ., Clean Product Mfg ., Metal Coating, Paper Mills and Products, Plastics and Resins, and Waste Management . EPA’s list of facilities does not include any of those that are permitted to discharge into Graham WWTP . In 2019, North Carolina’s Department of Environmental Quality (DEQ) determined that the Graham WWTP’s influent was contaminated with PFAS . DEQ’s sampling105 detected the presence of 13 PFAS; three of which were detected at concentra- tions greater than 10 ppt: PFHxA (max . 11 .8 ppt), PFPeA (max . 65 .6 ppt), and PFOS (max . 12 .8 ppt) . That same year, Haw Riverkeeper tested water samples collected upstream and downstream of WWTPs along the Haw, including the Graham WWTP . Water samples taken from upstream and downstream of the facility outfall detected total PFAS concentrations of 33 .14 ppt (upstream) and 44 .75 ppt (downstream) . For this project, Haw Riverkeeper deployed PFASsive™ passive sampling devices immediately upstream and downstream from a Graham WWTP’s outfall to the Haw River from August 12, 2024 to September 20, 2024 . Both upstream and downstream sampling sites detected mul- tiple types of PFAS . However, total PFAS concentrations increased significantly at the downstream site, rising by 66 .47 ppt or 85 .14% . For example, the concentration of PFPeA increased from 14 ppt to 36 ppt (157 .14%), the concentration of PFDA increased from 1 .2 ppt to 2 .6 ppt Graham WWTP | Haw River PFAS Phase II Sampling Site WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 5554 (116 .67%), and the concentration of PFHxA increased from 13 ppt to 27 ppt (107 .69%) . Multiple other types of PFAS increased in downstream samples at levels ranging from 7 .14% to 91 .01%, including PFBS which increased from 8 .9 ppt to 17 ppt . These results are consistent with the findings of previous sampling and indicate that the Graham WWTP’s outfall is likely a significant source of PFAS in the Haw River . Downstream concentrations of PFAS demonstrate that the surface water is unsafe for drinking without advanced treatment . For example, the concentration of PFOA at the downstream location was 10 ppt, which is 6 ppt greater than the MCL of 4 ppt, and the concentration of PFOS was 23 ppt, which is 19 ppt greater than the MCL of 4 ppt . The concentrations of PFOA and PFOS in the down- stream samples were also greater than the draft HHWQC (Water + Organism) . Specifically, PFOA exceeded the criteria of 0 .0009 ppt by 9 .9991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 22 .94 ppt . There are no national or state CWA surface water quality criteria for the protection of human health that apply to the majority of PFAS that were detected at elevated levels, including PFPeA, PFHxA, PFBA, PFHpA, PFDA, 6:2 FTS, PFMPA, PFUnA, PFNA, PFDoA, and PFHxS . Additionally, numerous PFAS that do not have any federal or state regulatory standards significantly exceeded EWG’s health-based criteria, including PFDA (also detected in 2019 NCDEQ Influent Sampling), PFUnA, PFDoA (also detected in 2019 NCDEQ Influent Sampling), and 6:2 FTS (also detected in 2019 NCDEQ Influent Sampling) . PFNA and PFHxS also significantly exceeded EWG’s health-based criteria . See Ta ble 17 (below). In addition to directly discharging wastewater into the Haw River, Graham WWTP is permitted106 to oper- ate a Residuals Land Application Program to land apply biosolids at nine fields owned by the City of Graham, all of which are located in the Haw River watershed . Graham WWTP produces Class B biosolids, and in 2023, Graham WWTP generated and land-applied 151 .296 dry tons of its biosolids to six of the nine land application fields—a total of 51 .6 acres .107 In 2024, Graham WWTP land-applied 217 .703 dry tons of its biosolids .108 For this project, Haw Riverkeeper also deployed PFASsive™ passive sampling devices in the Haw Creek immediately upstream and downstream from land appli- cation sites receiving biosolids from Graham WWTP . Those sampling devices were deployed from August 12, 2024 to September 20, 2024 . Both upstream and downstream sam- pling sites detected multiple types of regulated and unregu- lated PFAS . It is notable that the upstream location had very high concentrations of certain types of PFAS, including PFOA and PFOS, as well as elevated concentrations of other PFAS . The concentration of total PFAS increased at the downstream site by 3 .91 ppt—an increase of 3 .81% . For example, the con- centration of PFBS increased from a non-detect to 5 .3 ppt, and PFBA increased from a non-detect to 3 .9 ppt . Like the samples taken downstream from Graham WWTP’s outfall, the PFAS concentrations downstream from Graham’s land application site demonstrate that the surface water is unsafe for drinking without advanced treatment . For example, the concentration of PFOA at the downstream location was 29 ppt, which is 25 ppt greater than the MCL of 4 ppt, and the concentration of PFOS was 34 ppt, which is 30 ppt greater than the MCL of 4 ppt . The concentrations of PFOA and PFOS in the downstream samples also greatly exceeded draft HHWQC (Water + Organism), indicating that concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 28 .9991 ppt, and PFOS exceeded the Table 17 | Haw River Upstream and Downstream from Graham WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFPeA 14.00 36.00 22.00 157.14%1000 PFHxA 13.00 27.00 14.00 107.69%1000 PFBS 8.90 17.00 8.10 91.01%400 2000 PFOS 17.00 23.00 6.00 35.29%4 19.00 0.06 22.94 0.3 22.700 PFBA 5.10 9.20 4.10 80.39%1000 PFHpA 5.20 8.80 3.60 69.23%1000 PFOA 7.10 10.00 2.90 40.85%4 6.00 0.0009 9.9991 0.09 9.910 PFDA 1.20 2.60 1.40 116.67%0.006 2.594 6:2 FTS 0.00 1.10 1.10 n/a 1 0.100 PFMPA 0.00 0.88 0.88 n/a 1 PFUnA 0.00 0.87 0.87 n/a 0.006 0.864 PFNA 1.50 2.20 0.70 46.67%10 0.006 2.194 PFDoA 0.00 0.59 0.59 n/a 0.006 0.584 PFHxS 4.20 4.50 0.30 7.14%10 0.001 4.499 PFPeS 0.87 0.80 -0.07 -8.05%1 Total PFAS 78.07 144.54 66.47 85.14% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Graham WWTP Biosolids Fields | Haw Creek PFAS Phase II Sampling Site Biosolids Land Application Sites WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 5756 0 .06 ppt criteria by 33 .94 ppt . There are no national or state Clean Water Act surface water quality criteria for the protection of human health that apply to the majority of PFAS that were detected at elevated levels, including PFBA, PFPeS, PFNA, PFHpS, and PFDA . Additionally, numerous PFAS that do not have any fed- eral or state regulatory standards significantly exceeded EWG’s health-based criteria, including PFDA, PFPeS, and PFHpS . Elevated levels of PFNA also significantly exceeded EWG’s health-based criteria . See Ta ble 18 (above). This evaluation indicates that Graham WWTP and its biosolids land application site in Haw Creek are con- tributing PFAS to the Haw River and that multiple indus- trial dischargers are likely contributing to the WWTP’s discharge of PFAS to the river . This pollution will likely continue to create significant risks to human health until PFAS pretreatment limits are placed on industrial sources of PFAS discharging into the WWTP and PFAS limits are placed in the Graham WWTP’s NPDES permit, which will require installation of PFAS treatment technology, limits on biosolids land application, and a plan to safely manage PFAS removed during the treatment process . Detroit Riverkeeper, Rouge River, Michigan Wastewater Treatment Plant Site The Great Lakes Water Authority Water Resource Recovery Facility (GLWA WRRF) is a municipal wastewater treat- ment system that is owned and operated by the City of Detroit Board of Water Commissioners . This facility serves a population of approximately 2 .8 million residents and is considered “the largest single-site treatment facility in North America .”109 GLWA WRFF accepts discharges from 234 permitted industrial users . GLWA WRRF discharges wastewater into the Rouge River and other locations .110 The Rouge River is a tributary to the Detroit River and contributes to the Great Lakes Basin, one of the larg- est freshwater ecosystems, and the watershed is home to 1 .35 million people in Oakland, Washtenaw, and Wayne counties . The GLWA Wastewater Master Plan states that “[t]he permitted peak primary treatment capacity is 1,700 MGD (the largest in the nation) and the peak secondary treat- ment capacity is 930 MGD .”111 According to ECHO, GLWA WRRF is located in an area with 13 State Supplemental EJ Indexes and 13 Federal Supplement EJ Indexes greater than the 80th percentile within one mile of the facility, including wastewater discharges at 99 (State) .112 According to the EPA EJScreen, of people living within one mile of GLWA WRRF, 59% are people of color and 65% are low income .113 The NPDES permit for GLWA WRRF requires quar- terly monitoring and reporting of PFAS in the facility’s effluent . The permit also requires that GLWA WRRF submit a Pollutant Minimization and Source Evaluation Program for Perfluorooctane Sulfonate (PFOS) and/ or Perfluorooctanoic Acid (PFOA) that will “identify and address sources of [PFOS] and/or [PFOA] and to reduce and maintain the effluent concentrations of PFOS and/or PFOA at or below the water quality standards (WQS) and/ or the Water Quality-Based Effluent limit (WQBEL) .”114 The 2019 permit includes a goal of meeting the water qual- ity standard for PFOS of 11 ppt and a WQBEL for PFOA of 8,040 ppt . For comparison, the EPA and MI MCLs are 4 ppt and 8 ppt respectively for PFOA and the National Recommended Ambient Water Quality Criteria for the Protection of Human Health includes a EPA Water + Organism Human Health Criteria of 0 .0009 ppt for PFOA . Beyond these requirements, however, the permit does not include any limits on the amount of PFAS the facility discharges . In terms of the facilities’ industrial dischargers, GLWA WRRF has adopted a Local Limit for PFOS of 65 ppt (Daily Maximum) .115 GLWA WRRF conducted PFAS sampling of the influ- ent from these industrial users as part of its Pollutant Minimization and Source Evaluation Program .116 Based on its sampling, GLWA WRRF classified 48 of these facilities as “Significant Sources” and five as “Potential Sources” of PFOS and/or PFOA .117 There are likely additional unpermitted industrial dischargers contributing PFAS to the WRRF given that EPA’s PFAS Analytic Tools118 identifies 217 facilities located within the City of Detroit that are “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemicals,” including: • Airports • Cement Mfg . • Chemical Mfg . • Cleaning Product Mfg . • Consumer Products • Fire Training • Glass Products • Industrial Gas • Metal Coating • Metal Machinery Mfg . • Oil and Gas • Paints and Coatings • Paper Mills and Products • Petroleum • Plastics and Resins • Printing • Waste Management Michigan’s Department of Environment, Great Lakes, and Energy (EGLE) conducted PFAS sampling of GLWA WRRF’s influent and effluent from 2018 to 2020 . The results showed significant concentrations of PFOA (6 .4 ppt to 12 ppt) and PFOS (5 .7 ppt to 30 ppt) in the facility’s efflu- ent, and equally high concentrations in the facility’s influent, including PFOA concentrations ranging from 4 .64 ppt to 9 .10 ppt and PFOS concentrations ranging from 7 .54 ppt to 15 .60 ppt .119 Further, as part of its Pollutant Minimization and Source Evaluation Program, GLWA WRRF collected quarterly samples of its discharges during 2023 and tested Table 18 | Haw Creek Upstream and Downstream from Biosolids Site Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBS 0 5.3 5.3 n/a 400 2000 PFBA 0 3.9 3.9 n/a 1000 PFPeS 0 2.2 2.2 n/a 1 1.2 PFNA 0 1.9 1.9 n/a 10 0.006 1.894 PFHpS 0 1.3 1.3 n/a 0.001 1.299 PFDA 0 0.81 0.81 n/a 0.006 0.804 PFPeA 6.5 6.1 -0.4 -6.15%1000 PFHxA 9.5 8.8 -0.7 -7.37%1000 PFOS 36 34 -2 -5.56%4 30 0.06 33.94 0.3 33.7 PFHxS 7.6 5.5 -2.1 -27.63%10 0.001 5.499 PFOA 32 29 -3 -9.38%4 25 0.0009 28.9991 0.09 28.91 PFHpA 11 7.7 -3.3 -30.00%1000 Total PFAS 102.6 106.51 3.91 3.81%d criteria levels Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 5958 them for 28 PFAS chemicals . The results showed annual average concentrations of PFOA at 8 .5 ppt (max . 11 .5 ppt) and PFOS at 13 .8 ppt (max . 26 .5 ppt) .120 The testing also detected other PFAS chemicals in the facility’s effluent, including: • PFBA (max . 19 ppt) • PFPeA (max . 13 ppt) • PFHxA (max . 23 ppt) • PFBS (max . 26 ppt) • PFHpA (max . 4 .6 ppt) • 6:2 FTSA (max . 8 .5 ppt) • PFHxS (max . 8 .2 ppt)121 For this project, Detroit Riverkeeper deployed PFASsive™ passive sampling devices upstream and down- stream from one of the GLWA WRRF’s outfalls (Outfall 050) and the Oakwood Combined Sewer Overflow Retention Basin channel from August 8, 2024 to September 8, 2024 .122 Both upstream and downstream sampling sites detected multiple types of PFAS . However, the concen- trations of multiple types of PFAS increased significantly at the downstream site resulting in a total PFAS concen- tration increase of 49 .49 ppt—an increase of 146 .81% . For example, the concentration of PFOA increased from 3 .8 ppt to 44 ppt (1,057 .89%) and the concentration of PFHxS increased from 1 .8 ppt to 16 ppt (788 .89%) . Other types of PFAS increased in downstream samples at levels ranging from 19 .23% to 48 .39%, including PFHxA which increased from 6 .2 ppt to 9 .2 ppt . These results are con- sistent with the findings of previous sampling and indicate that the GLWA WRRF is likely a significant source of PFAS in the Rouge River . Downstream concentrations of PFAS demonstrate that the surface water as this location is likely unsafe for drink- ing without advanced treatment . For example, the concen- tration of PFOA at the downstream location was 44 ppt, which is 40 ppt greater than the MCL of 4 ppt, and the concentration of PFHxS was 16 ppt, which is 6 ppt greater than the MCL of 10 ppt . PFOA also exceeded Michigan’s MCL (16 ppt) by 36 ppt .123 The concentrations of PFOA and PFOS in the down- stream samples also greatly exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 43 .9991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 3 .04 ppt . There are no national or state Clean Water Act surface water quality criteria for the protection of human health that apply to the majority of PFAS that were detected at elevated levels, including PFHxS, PFDA, and PFHxA . Other PFAS that do not have any federal or state regulatory standards exceeded EWG’s health-based criteria, including PFDA and 6:2 FTS . PFOA, PFHxS, and PFOS also exceeded EWG’s health-based criteria . See Ta ble 19 (above). This evaluation indicates that GLWA WRRF appears to be contributing a significant amount of PFAS to the Rouge River and that multiple industrial dischargers are likely contributing to the WRRF’s discharge of PFAS to the river . This pollution will likely continue to create significant risks to human health until additional PFAS pretreatment limits are placed on industrial sources of PFAS discharging into the WRRF and more protective, mandatory permit limits are placed in the GLWA WRRF’s NPDES permit, which will require installation of PFAS treatment technology and a plan to safely manage PFAS removed during the treatment process . Assessment of the two outlets contributions of PFAS to the Rouge River is also warranted and may result in the need for additional controls in those areas . Table 19 — Rouge River Upstream and Downstream from GLWA WRRF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)MI MCL (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFOA 3.80 44.00 40.20 1057.89%4 40.00 0.0009 43.9991 0.09 43.910 8 36 PFHxS 1.80 16.00 14.20 788.89%10 6.00 0.001 15.999 51 PFDA 0.00 5.00 5.00 n/a 0.006 4.994 PFHxA 6.20 9.20 3.00 48.39%1000 400,000 PFOS 2.60 3.10 0.50 19.23%4 0.06 3.04 0.3 2.800 16 PFHpA 1.60 1.60 0.00 0.00%1000 6:2 FTS 1.50 1.30 -0.20 -13.33%1 0.300 PFNA 0.61 0.00 -0.61 -100.00%10 0.006 6 FOSA 1.30 0.00 -1.30 -100.00%0.3 PFPeA 4.30 1.70 -2.60 -60.47%1000 PFBS 4.50 1.30 -3.20 -71.11%400.00 2000 420 PFBA 5.50 0.00 -5.50 -100.00%1000 Total PFAS 33.71 83.20 49.49 146.81% Non-detect recorded as 0 Downstream Increase Exceed criteria levels GLWA WRRF | Rouge River PFAS Phase II Sampling Site WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 6160 Potomac Riverkeeper, Monocacy River, Maryland Wastewater Treatment Plant and Biosolids Sites The City of Frederick WWTP (Frederick WWTP) is a munic- ipal wastewater treatment system that is owned and operated by the City of Frederick and serves a population of 73,000 residents .124 In addition, the facility handles wastewater from two permitted Significant Industrial Users .125 The Frederick WWTP discharges wastewater into the Lower Monocacy River at an average design flow of 8 MGD .126 The Lower Monocacy Watershed covers 194,790 acres and is home to 7,626 residents . According to the EJScreen Community Report for this facility, Frederick WWTP is located in an area with two State Supplemental EJ Indexes greater than the 80th percentile within one mile of the facility, including wastewater discharges at 80 (State) . According to the EPA EJScreen, of people living within one mile of Frederick WWTP, 37% are people of color and 15% are low income .127 The NPDES permit for Frederick WWTP does not include any limits on the amount of PFAS the facility dis- charges into the Monocacy River and there are no pre- treatment limits to control PFAS discharges to the WWTP by industrial dischargers .128 Neither of Frederick WWTPs permitted industrial users are included in EPA’s PFAS Analytic Tools129 as facilities “operat[ing] in sectors that have been identified as possibly handling, using, or releas- ing PFAS chemicals .” There are likely additional unpermit- ted industrial dischargers contributing PFAS to the WWTP given that EPA’s PFAS Analytic Tools identifies 40 facilities located within the City of Frederick that operate in related sectors, including: • Airports • Cement Mfg . • Chemical Mfg . • Cleaning Product Mfg . • Electronics Industry • Furniture and Carpet • Metal Coating • Metal Machinery Mfg . • Mining and Refining • National Defense • Paints and Coatings • Petroleum • Printing • Textiles and Leather • Waste Management For this project, Potomac Riverkeeper deployed PFASsive™ passive sampling devices immedi- ately upstream and downstream from a Frederick WWTP outfall to the Monocacy River from August 13, 2024 to September 6, 2024 . Both upstream and downstream sampling sites detected multi- ple types of PFAS . However, the concentrations of eight types of PFAS increased at the down- stream site resulting in a total PFAS concentration increase of 33 .64 ppt—an increase of 128 .01% . For example, the concentration of PFPeA increased from 4 .2 ppt to 22 ppt (423 .81%), the concentra- tion of PFHxA increased from 3 .4 ppt to 13 ppt (282 .35%), and the concentration of PFHxS increased from 1 .1 ppt to 2 .5 ppt (127 .27%) . Multiple other types of PFAS increased in down- stream samples at levels ranging from 18 .92% to 83 .78%, including PFOA which increased from 3 .7 ppt to 6 .8 ppt . These results indicate that the Frederick WWTP’s outfall is likely a significant source of PFAS in the Monocacy River . Downstream concentrations of PFAS demonstrate that the surface water is unsafe at this location for drinking without advanced treatment . For example, the concen- tration of PFOA at the downstream location was 6 .8 ppt, which is 2 .8 ppt greater than the MCL of 4 ppt . The concentrations of PFOA and PFOS in the down- stream sample also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 6 .7991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 3 .04 ppt . There are no national or state Clean Water Act surface water quality criteria for the protection of human health that apply to the majority of PFAS that were detected at elevated levels, including PFPeA, PFHxA, PFHxS, PFHpA, PFBA, and FOSA . FOSA does not have any federal or state regulatory standards but exceeded EWG’s health-based criteria . PFOA, PFHxS, and PFOS also significantly exceeded EWG’s health-based criteria . See Ta ble 20 (below). Frederick WWTP contracts with Synagro Central, LLC to haul and land apply the facility’s biosolids . Potomac Riverkeeper conducted PFAS sampling upstream and downstream from the biosolids land application site at the Baumgartner & Zack Property, one of Synagro’s land application sites, which is located in the Monocacy River watershed that is approved for biosolids application from the Frederick WWTP and other WWTPs .130 Samples of the Monocacy River upstream and down- stream from the biosolids land application site contained PFAS .131 However, the concentrations of multiple types of PFAS increased at the downstream site resulting in a total PFAS concentration increase of 0 .75 ppt—an increase of 2 .75% . For example, the concentration of PFBS increased from 3 .5 ppt to 3 .9 ppt (11 .43%), and PFNA increased City of Frederick WWTP | Monocacy River PFAS Phase II Sampling Site Table 20 | Monocacy River Upstream and Downstream from Frederick WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFPeA 4.20 22.00 17.80 423.81%1000 PFHxA 3.40 13.00 9.60 282.35%1000 PFOA 3.70 6.80 3.10 83.78%4 2.80 0.0009 6.7991 0.09 6.710 PFBS 3.60 5.00 1.40 38.89%400 2000 PFHxS 1.10 2.50 1.40 127.27%10 0.001 2.499 PFHpA 1.70 2.50 0.80 47.06%1000 PFBA 3.70 4.40 0.70 18.92%1000 FOSA 0.00 0.62 0.62 n/a 0.3 0.320 PFNA 0.68 0.00 -0.68 -100.00%10 0.006 PFOS 4.20 3.10 -1.10 -26.19%4 0.06 3.0400 0.3 2.800 Total PFAS 26.28 59.92 33.64 128.01% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 6362 from a non-detect to 0 .77 ppt . Other types of PFAS increased in downstream samples at levels ranging from 5 .08% to 11 .36% . The concentration of PFOS at the downstream loca- tion was 5 .5 ppt, which is 1 .5 ppt greater than the MCL of 4 ppt, rendering the surface water at this location unsafe for drinking without advanced treatment . PFOA and PFOS concentrations also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 3 .6991 ppt, and PFOS exceeded the draft HHWQC (Water + Organism) of 0 .06 ppt by 5 .44 ppt . PFOA, PFNA, PFHxS, and PFOS also exceeded the EWG health-based criteria . See Ta ble 21 (above). This evaluation indicates that Frederick WWTP is contributing PFAS to the Monocacy River and that multiple industrial dischargers to the WWTP are likely contributing to the discharge of PFAS to the river . This pollution will likely continue to create significant risks to human health until PFAS pretreatment lim- its are placed on industrial sources of PFAS discharging into the WWTP and a PFAS limit is placed in the Frederick WWTP’s NPDES permit, which will require installation of PFAS treat- ment technology and a plan to safely manage PFAS removed during the treatment process . Tualatin Riverkeepers, Tualatin River, Oregon Wastewater Treatment Plant Site The Tualatin River Watershed spans 712 square miles and is home to over 600,000 Oregon residents . The Tualatin River flows approximately 83 miles from the Coast Mountain Range to the Willamette River . Fed by more than 900 miles of tributary streams, the river serves as a drinking water source for 400,000 people . The Rock Creek WRRF, which discharges into the Tualatin River, is a municipal wastewater treatment system that is owned and operated by Clean Water Services (CWS) and serves a population of approximately 326,488 residents .132 In addition, the facility handles wastewater from numerous industrial dischargers, including five permitted Significant Industrial Users (SIUs) and 15 permitted Categorical Industrial Users (CIUs) . Clean Water Services also owns and operates three other water resource recovery facilities that receive discharges from an additional seven SIUs and 12 CIUs . Rock Creek WRRF “is designed to treat an average dry season flow of 52 .7 MGD (projected for 2025 conditions and with no discharge from the Hillsboro and Forest Grove WRRFs) and a daily maximum wet weather flow of 126 MGD .”133 According to ECHO, Rock Creek WRRF is located in an area with 11 State Supplemental EJ Indexes and 11 Federal Supplemental EJ Indexes greater than the 80th percentile within one mile of the facility, includ- ing wastewater discharges at 99 (State) .134 According to the EPA EJScreen, of people living within one mile of Rock Creek WRRF, 45% are people of color and 17% are low income .135 Clean Water Services’ 2022 Annual Report states that CWS monitors for PFAS at its STPs .136 However, its NPDES permit137 does not include any limits on the amount of PFAS the Rock Creek WRRF discharges into the Tualatin River, and there are no pretreatment limits to control PFAS discharges to the facility by industrial dischargers . Of Clean Water Services’ 39 permitted industrial users, EPA’s PFAS Analytic Tools138 lists the following 11 as facilities “operat[ing] in sectors that have been identified as possi- bly handling, using, or releasing PFAS chemicals”: • Linde Inc . (Industrial Gas) • TOK America (Chemical Mfg .) • Analog Devices (formerly Maxim Integrated Products) (Electronics Industry) • BASF Corporation (Chemical Mfg .) • Hillsboro Landfill, Inc . (Waste Management) • Intel Corporation — Ronler Acres Campus (Electronics Industry) • Jireh Semiconductor, Inc . (Electronics Industry) • KoMiCo Hillsboro, LLC (Metal Coating) • Qorvo U .S . Inc . (Electronics Industry) • QuantumClean (Metal Coating) • Sumitomo Electric Semiconductor Materials, Inc . (Electronics Industry There are likely additional unpermitted industrial discharg- ers contributing PFAS to the Rock Creek WRRF given that EPA’s PFAS Analytic Tools identifies 51 facilities located within the City of Hillsboro that operate in related sec- tors, including: • Airports • Chemical Mfg . • Electronics Industry • Industrial Gas • Metal Coating • Metal Machinery Mfg . • Plastics and Resins • Printing • Waste Management Of the 20 permitted industrial users discharging wastewater specifically to Rock Creek WRRF, Clean Water Services has identified Intel Corporation — Ronler Acres Campus and Hillsboro Landfill as being the major indus- trial sources of PFAS to Rock Creek WRRF .139 The majority of Intel Corporation’s contribution appears to have signifi- cantly decreased after 2019, while Hillsboro Landfill con- tinues to contribute significant concentrations of multiple types of PFAS from landfill leachate to Rock Creek WRRF . Table 21 | Monocacy River Upstream and Downstream from Biosolids Land Application Fields Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)MD DW (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 5.9 6.2 0.30 5.08%1000 PFHxA 4.4 4.9 0.50 11.36%1000 PFHpA 2.0 2.2 0.20 10.00%1000 PFOA 4.6 3.7 -0.90 -19.57%4 0.0009 3.6991 0.09 3.61 PFNA 0.00 0.77 0.77 n/a 10 0.006 0.764 PFBS 3.5 3.9 0.40 11.43%400 2000 PFHxS 0.87 0.85 -0.02 -2.30%10 0.001 0.849 140 PFOS 6.0 5.5 -0.50 -8.33%4 1.50 0.06 5.44 0.3 5.20 Total PFAS 27.27 28.02 0.75 2.75% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Synagro Central, LLC Biosolids Application Field | Monocacy River Biosolids Application Field WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 6564 Figure 18 | Clean Water Services Advisory Commission 2024 Meeting140 Other than these two facilities, it is unclear how many of EPA’s other listed facilities discharge into Rock Creek WRRF, rather than one of CWS’ other three facilities . However, according to Clean Water Services’ NPDES per- mit renewal application, Rock Creek WRRF may receive and treat flows from Hillsboro and Forest Grove depend- ing on the season and whether the flows exceed the facilities’ capacities .141 Thus, Rock Creek is likely receiving, either directly or indirectly, discharges from at least some of these industrial users operating in PFAS-related sectors . Clean Water Services has identified Rock Creek WRRF’s summer discharges as a dominant source of PFAS pollution in the Tualatin River .142 In particular, Clean Water Services has reported that Rock Creek WRRF’s effluent contributes PFBS, PFHxA, PFOS, PFOA, and PFPeA to the river . Figure 19 | Clean Water Services Advisory Commission 2024 Meeting143 700 600 500 400 300 200 100 0 25,000 20,000 15,000 10,000 5,000 0PFAS Concentration (ng/L) PFAS Concentration (ng/L) Effects of Source Control Efforts PFBA PFBS PFDA PFHpA PFHpS PFHxA PFHxS PFNA PFOS PFOA PFPeA 6:2FTS NMeFOSAA NEtFOSAA 4/13/2022 4/13/2022 8/4/20228/15/2019 8/15/20191/26/2023 1/26/20234/7/2023 4/7/20239/11/2023 9/11/202312/6/2023 12/6/2023 Intel Corporation — Ronler Acres Campus Hillsboro Landfill @ Cherry Grove @ Fernhill @ Golf Course @ Rood Bridge @Farmington @ Jurgens @ Boones Ferry 60 50 40 30 20 10 0PFAS Concentration (ng/L) Upper Tributaries ConcentrationsLower Tributaries ConcentrationsScoggins Below Hagg Gales @ Stringtown Dairy @ Hwy 8 Rock @ Brookwood Rock Creek Effluent Chicken @ Sholls-Sherwood Durham Effluent Fanno @ Durham Rd 60 50 40 30 20 10 0 60 50 40 30 20 10 0 Sources of PFAS in the Watershed Measurements Taken Along the Tualatin River PFBS PFBA PFDA PFHpA PFHxA PFHxS PFNA FOSA PFOA PFOS PFPeA PFPeS TREATMENT / REUSE INSTALLED EXTERNAL LEACHATE DISALLOWED WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 6766 For this project, Tualatin Riverkeepers deployed PFASsive™ passive sampling devices upstream and downstream from two Rock Creek WRRF outfalls from August 9, 2024 to September 19, 2024 . The downstream sampling site detected multiple types of PFAS . However, the upstream sample only showed trace levels of PFOS at 0 .97 ppt . The concentrations of multiple types of PFAS increased significantly at the downstream site resulting in a total PFAS concentration increase of 29 .05 ppt—an increase of 2,994 .85% . For example, the concentration of PFHxA increased from a non-detect to 7 .1 ppt, the con- centration of PFBA increased from a non-detect to 6 .2 ppt, and the concentration of PFOS increased from 0 .97 ppt to 2 .5 ppt (157 .73%) . These results are consistent with the findings of previous sampling and indicate that the Rock Creek WRRF’s outfall is likely a significant source of PFAS in the Tualatin River . The concentrations of PFOA and PFOS in the down- stream samples greatly exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 3 .2991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 2 .44 ppt . There are no national or state Clean Water Act surface water quality criteria for the protection of human health that apply to the majority of PFAS that were detected at elevated levels, including PFHxA, PFBA, PFPeA, PFHpA, PFHxS, and PFNA . Additionally, PFOA, PFOS, PFNA and PFHxS exceeded EWG’s health guide- lines . See Ta ble 22 (below). This evaluation indicates that Rock Creek WRRF is contributing PFAS to the Tualatin River and that multiple industrial dischargers are likely contributing to the WRRF’s discharge of PFAS to the river . This pollution will likely con- tinue to create significant risks to human health until PFAS pretreatment limits are placed on industrial sources of PFAS discharging into the STP and a PFAS limit is placed in the Rock Creek WRRF’s NPDES permit, which will require instal- lation of PFAS treatment technology and a plan to safely manage PFAS removed during the treatment process . Rock Creek WRRF | Tualatin River PFAS Phase II Sampling Site Inland Empire Waterkeeper, Santa Ana River, California Wastewater Treatment Plant Site The Riverside RWQCP is a municipal wastewater treat- ment system that is owned and operated by the City of Riverside’s Department of Public Works and serves a population of more than 300,000 .144 In addition, the facility handles wastewater from numerous industrial dischargers, including 10 permitted Class I, Significant Industrial Users and two permitted Categorical Industrial Users . Riverside RWQCP discharges wastewater into the Santa Ana River at an average design flow of 46 MGD . The Santa Ana River Watershed covers 2,630 square miles across San Bernardino, Riverside, Orange, and Los Angeles Counties . According to ECHO, Riverside RWQCP is located in an area with 11 State Supplemental EJ Indexes and 13 Federal Supplement EJ Indexes greater than the 80th percentile within one mile of the facility, including wastewater dis- charges at 97 (Federal) .145 According to the EPA EJScreen, of people living within one mile of Riverside RWQCP, 80% are people of color and 34% are low income .146 The NPDES permit147 for Riverside RWQCP does not include any limits on the amount of PFAS the facility dis- charges into the Santa Ana River and there are no pretreat- ment limits to control PFAS discharges to the RWQCP by industrial dischargers . Of the 12 permitted industrial users discharging wastewater to Riverside RWQCP, EPA’s PFAS Analytic Tools148 lists one facility as “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemicals”: Von Zabern Surgical (Waste Management) . There are likely additional unpermitted industrial dischargers contributing PFAS to the RWQCP given that EPA’s PFAS Analytic Tools identifies 61 active facilities located within the City of Riverside that operate in PFAS-related sectors, including: • Airports • Cement Mfg . • Chemical Mfg . • Cleaning Product Mfg . • Electronics • Fire Protection • Industrial Gas • Metal Coating • Metal Machinery Mfg . • Mining and Refining • National Defense • Paints and coatings • Petroleum • Plastics and Resins • Printing • Textiles and Leather • Waste Management Based on 2021 sampling data collected by Riverside RWQCP, the facility’s influent,149 effluent,150 and biosol- ids151 contain significant concentrations of PFAS . The PFAS detected at the highest concentrations in the facility’s influent, effluent, and biosolids were PFPeS (46 ppt), PFPeA (63 ppt), and 5:3 FTCA (140 ug/kg), respectively . For this project, Inland Empire Waterkeeper conducted two rounds of sampling . It first deployed PFASsive™ passive sampling devices immediately downstream from a Riverside RWQCP’s outfall to the Santa Ana River from Riverside RWQCP | Santa Ana River PFAS Phase II Sampling Site Table 22 | Tualatin River Upstream and Downstream from Rock Creek WRRF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFHxA 0.00 7.10 7.10 N/A 1000 PFBA 0.00 6.20 6.20 N/A 1000 PFPeA 0.00 4.40 4.40 N/A 1000 PFBS 0.00 3.50 3.50 N/A 400 2000 PFOA 0.00 3.30 3.30 N/A 4 0.0009 3.2991 0.09 3.210 PFHpA 0.00 1.70 1.70 N/A 1000 PFOS 0.97 2.50 1.53 157.73%4 0.06 2.4400 0.3 2.200 PFHxS 0.00 0.73 0.73 N/A 10 0.001 0.729 PFNA 0.00 0.59 0.59 N/A 10 0.006 0.584 Total PFAS 0.97 30.02 29.05 2994.85% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 6968 August 14, 2024 to September 11, 2024 . Two months later, Inland Empire Waterkeeper conducted its second round of sampling by deploying sampling devices downstream as well as upstream of a facility outfall to the Santa Ana River from November 11, 2024 to December 18, 2024 . Both upstream and downstream sampling sites detected multiple types of PFAS .152 However, the sampling devices deployed in November detected two PFAS that increased in concentration significantly at the downstream site result- ing in a total PFAS concentration increase of 27 .43 ppt—an increase of 30 .58% . Specifically, the concentration of PFHxA increased from 11 ppt to 27 ppt (145 .45%) and the concentration of PFPeA increased from 12 ppt to 43 ppt (258 .33%) . Downstream concentrations of PFAS demonstrate that the surface water at this location is unsafe for drinking without advanced treatment . For example, the concen- tration of PFOA at the downstream location in November and August was 10 ppt and 13 ppt, respectively, which are 6 ppt and 9 ppt greater than the MCL, and the concentra- tion of PFOS was 6 .8 ppt and 12 ppt, respectively, which are 2 .8 ppt and 8 ppt greater than the MCL . The concentrations of PFOA and PFOS in the down- stream samples also greatly exceeded the draft HHWQC, indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general pop- ulation from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the November downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 9 .9991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 6 .74 ppt . In the August downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) by 12 .9991 ppt, and PFOS exceeded the criteria by 11 .94 ppt . There are no national or state Clean Water Act surface water quality criteria for the protec- tion of human health that apply to certain PFAS that were detected at elevated levels, including PFPeA and PFHxA . Additionally, PFOA and PFOS exceeded California’s Public Health Goal of 0 .007 ppt (PFOA) and 1 ppt (PFOS) .153 The November downstream sample detected PFOA and PFOS concentrations that exceeded the Public Health Goal by 9 .993 ppt and 5 .8 ppt, respectively, and the August downstream sample detected PFOA and PFOS concentrations that exceeded the Public Health Goal by 12 .993 ppt and 11 ppt, respectively . Further, both the November and August downstream samples exceeded California’s Notification Level of 3 ppt for PFHxS by 4 .7 ppt .154 Finally, numerous PFAS significantly exceeded EWG’s health-based criteria, including PFDA (Aug .), PFPeS (Nov . and Aug .), and PFMBA (Aug .) . PFOA (Nov . and Aug .), PFOS (Nov . and Aug .), PFNA (Nov . and Aug .) and PFHxS (Nov . and Aug .) also exceeded EWG’s health-based crite- ria . See Table 23 (p. 71). This evaluation indicates that Riverside RWQCP is contributing PFAS to the Santa Ana River and that multiple industrial dischargers to the RWQCP are likely contribut- ing to the RWQCP’s discharge of PFAS to the river . This pollution will likely continue to create significant risks to human health until PFAS pretreatment limits are placed on industrial sources of PFAS discharging into the RWQCP and a PFAS limit is placed in the Riverside RWQCP’s NPDES permit, which will require installation of PFAS treatment technology and a plan to safely manage PFAS removed during the treatment process . Table 23 | Santa Ana River Upstream and Downstream from Riverside RWQCP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)CA Public Health Goal (ppt) CA Notification Level (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance November PFPeA 12.00 43.00 31.00 258.33% PFHxA 11.00 27.00 16.00 145.45%1000 PFDA 0.00 0.00 0.00 0.00%0.006 PFMBA 0.00 0.00 0.00 0.00%1 PFNA 1.00 0.73 -0.27 -27.00%10 0.006 0.724 PFHpA 3.50 2.70 -0.80 -22.86%1000 PFOA 11.00 10.00 -1.00 -9.09%4 6.00 0.0009 9.9991 0.09 9.910 0.007 9.993 PFPeS 2.90 1.50 -1.40 -48.28%1 0.500 PFBA 13.00 11.00 -2.00 -15.38%1000 PFBS 9.30 6.70 -2.60 -27.96%400 2000 500 PFOS 11.00 6.80 -4.20 -38.18%4 2.80 0.06 6.7400 0.3 6.500 1 5.800 PFHxS 15.00 7.70 -7.30 -48.67%10 0.001 7.699 3 4.70 Total PFAS 89.70 117.13 27.43 30.58% August (no upstream sampling) PFPeA n/a 24.00 n/a n/a 1000 PFHxA n/a 20.00 n/a n/a 1000 PFDA n/a 2.20 n/a n/a 0.006 2.194 PFMBA n/a 6.10 n/a n/a 1 5.100 PFNA n/a 2.10 n/a n/a 10 0.006 2.094 PFHpA n/a 3.60 n/a n/a 1000 PFOA n/a 13.00 n/a n/a 4 9 0.0009 12.9991 0.09 12.910 0.007 12.993 PFPeS n/a 1.20 n/a n/a 1 0.200 PFBA n/a 12.00 n/a n/a 1000 PFBS n/a 21.00 n/a n/a 400 2000 500 PFOS n/a 12.00 n/a n/a 4 8 0.06 11.9400 0.3 11.700 1 11.000 PFHxS n/a 7.70 n/a n/a 10 0.001 7.699 3 4.7 Total PFAS —124.90 —— Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 7170 Milwaukee Riverkeeper, Root River and Spring Creek, Wisconsin Wastewater Treatment Plant and Biosolids Sites The Waukesha WWTP is a municipal wastewater treat- ment system that is owned and operated by the City of Waukesha that serves a population of 73,000 people .155 In addition, the facility handles wastewater from 30 permitted industrial dischargers, including six Significant Industrial Users and 18 Categorical Industrial Users . Waukesha WWTP’s permit was issued in 2019, at that time, Waukesha WWTP was discharging solely to the Fox River at an annual average design flow of 14 MGD . The permit, however, incorporates Waukesha WWTP’s plans to start discharging most of its effluent to the Root River sometime “[d]uring the 5-year permit term .”156 This new discharge is based on approval of the first proposed Great Lakes diversion (for a community in a straddling county) under the Great Lakes Compact . In 2023, the upgrades necessary to transfer the majority of its discharges to the Root River were com- pleted .157 According to the permit, these discharges are allowed an annual average design flow of 9 .3 MGD . The Root River Watershed covers 198 square miles across parts of Waukesha, Milwaukee, and Racine counties in Wisconsin . It includes 117 miles of rivers and streams, including the Root River, which originates in southern Milwaukee County, and flows southeast into Lake Michigan . According to ECHO, Waukesha WWTP is located in an area with 13 State Supplemental EJ Indexes and 10 Federal Supplemental EJ Indexes greater than the 80th percentile within one mile of the facility, including wastewater dis- charges at 98 (State) .158 According to the EPA EJScreen, of people living within one mile of Waukesha WWTP, 28% are people of color and 28% are low income .159 The NPDES permit160 for Waukesha WWTP does not include any limits on the amount of PFAS the facility discharges into the Root River and there are no pretreat- ment limits to control PFAS discharges to the WWTP by industrial dischargers . Of the 30 permitted industrial users discharging wastewater to Waukesha WWTP, EPA’s PFAS Analytic Tools161 lists the following five as facili- ties “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemicals”: Gascoigne Co . (Metal Coating), GE Medical Systems, LLC (Electronics Industry), H .O . Bostrom Co . (Metal Coating), Profile Finishing Systems, LLC (Metal Coating), and Waukesha Memorial Hospital Inc . (Airports) . There are likely additional unpermitted industrial discharg- ers contributing PFAS to the WWTP given that EPA’s PFAS Analytic Tools identifies 40 facilities located within the City of Waukesha that operate in related sec- tors, including: • Airports • Chemical Mfg . • Clean Product Mfg . • Electronics Industry • Industrial Gas • Metal Coating • Metal Machinery Mfg . • Paints and Coatings • Printing • Textiles and Leather • Waste Management For this project, Milwaukee Riverkeeper deployed PFASsive™ passive sampling devices and duplicate devices immediately upstream and downstream from the Waukesha WWTP’s outfall to the Root River from August 14, 2024 to September 18, 2024 . Both upstream and downstream sampling sites detected multiple types of PFAS . However, the concentrations of nine types of PFAS increased at the downstream site, in both the primary and duplicate samples, resulting in a total PFAS concentration increase of 25 .76 ppt—an increase of 90 .26%—in the primary downstream sam- ple, and 25 .63 ppt (91 .21% increase) in the duplicate downstream sample . For example, in the primary and duplicate down- stream samples, the concentration of PFPeA increased from 5 .7 ppt to 18 ppt (215 .79%) and 5 .6 ppt to 18 ppt (221 .43%), respectively . The concentration of PFOA increased in the primary and duplicate downstream samples from 4 .2 ppt to 8 ppt (90 .48%) and 3 .9 ppt to 6 .4 ppt (64 .10%), respectively . Multiple other types of PFAS increased in downstream samples at levels ranging from 25% to 74 .07% in the primary samples and 10 .53% to 100% in the duplicate samples . These results indicate that the Waukesha WWTP’s outfall is likely a significant source of PFAS in the Root River . Downstream concentrations of PFAS demonstrate that the surface water at this location is unsafe for drinking without advanced treatment . For example, the concentration of PFOA at the primary downstream location was 8 ppt, which is 4 ppt greater than the MCL, and the con- centration of PFOS was 4 .4 ppt, which is 0 .4 ppt greater than the MCL . The concentrations of PFOA and PFOS in the downstream samples also exceeded the draft HHWQC (Water + Organism), indicating the concen- trations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the primary downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) Human Health Criteria of 0 .0009 ppt by 7 .9991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 4 .34 ppt . There are no national or state Clean Water Act surface water quality criteria for the protection of human health that apply to certain PFAS that were detected at elevated levels, including PFPeA, PFHxA, PFBA, PFHpA, PFHxS, and PFNA . Additionally, PFDA (duplicate sample) does not have any federal or state regulatory standards but exceeded EWG’s health-based criteria . PFOA, PFOS, PFNA and PFHxS (primary sample) also exceeded EWG’s health- based criteria . See Tab le 24 (below). In addition to directly discharging wastewater into the Root River, Waukesha WWTP is permitted162 to operate a Land Application Program to land apply its wastewa- ter treatment biosolids . In its 2017 permit application,163 Waukesha WWTP estimated that it would generate and Waukesha WWTP Outfall | Root River PFAS Phase II Sampling Site Table 24 | Root River Upstream and Downstream from Waukesha WWTP Analyte Sample (ppt)Duplicate Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFPeA 5.70 18.00 12.30 215.79%5.60 18.00 12.40 221.43%1000 PFOA 4.20 8.00 3.80 90.48%3.90 6.40 2.50 64.10%4 4.00 0.0009 7.9991 0.09 7.910 PFHxA 4.50 7.60 3.10 68.89%4.70 7.10 2.40 51.06%1000 PFBS 2.70 4.70 2.00 74.07%2.80 4.80 2.00 71.43%400 2000 PFOS 2.70 4.40 1.70 62.96%2.50 5.00 2.50 100.00%4 0.40 0.06 4.3400 0.3 4.100 PFBA 5.20 6.50 1.30 25.00%5.70 6.30 0.60 10.53%1000 PFHpA 1.30 1.90 0.60 46.15%1.40 1.90 0.50 35.71%1000 PFHxS 1.60 2.10 0.50 31.25%1.50 2.10 0.60 40.00%10 0.001 2.099 PFNA 0.64 1.10 0.46 71.88%0.00 1.30 1.30 n/a 10 0.006 1.094 PFDA 0.00 0.00 0.00 0.00%0.00 0.83 0.83 n/a 0.006 0.824 Total PFAS 28.54 54.30 25.76 90.26%28.10 53.73 25.63 91.21% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 7372 land apply a total of 1,352 dry tons of Class B, anaerobi- cally digested biosolids annually . Milwaukee Riverkeeper conducted PFAS sampling in Spring Creek upstream and downstream from multiple land application sites near East Troy, Wisconsin, in the Fox River watershed . In 2024, these fields received roughly 374 metric tons of Waukesha WWTP’s biosolids . The only PFAS detected at the sampling sites was PFBA, and it was only detected upstream of the biosolids land application fields at a concentration of 1 .1 ppt . The concentration of PFBA decreased to a non-detect—a 100% decrease—at the downstream site . See Ta ble 25 (above). This evaluation indicates that Waukesha WWTP is contributing PFAS to the Root River and that multiple industrial dischargers are likely contributing to the WWTP’s discharge of PFAS to the river . This pollution will likely continue to create significant risks to human health until PFAS pretreatment limits are placed on industrial sources of PFAS discharging into the WWTP and a PFAS limit is placed in the Waukesha WWTP’s NPDES permit, which will require installation of PFAS treatment technology and a plan to safely manage PFAS removed during the treatment process . Spokane Riverkeeper, Spokane River and Dragoon Creek, Washington Wastewater Treatment Plant and Biosolids Sites The Spokane Riverside Park WRF is a municipal wastewa- ter treatment system that is owned and operated by the City of Spokane that serves a population of approximately 255,000 residents .164 In addition, the facility handles wastewater from numerous industrial dischargers, includ- ing six permitted Categorical Industrial Users and eight permitted Significant Industrial Users . Spokane Riverside Park WRF discharges wastewater into the Spokane River at a Maximum Month Average Design Flow of 68 .1 MGD during the months of March to October, and 56 .4 MGD from November to February . The Spokane River flows 111 miles west from Lake Coeur d’Alene in Idaho into Washington State, where it empties into the Franklin D . Roosevelt Lake impoundment of the Columbia River . The Spokane Valley-Rathdrum Prairie aquifer, which sits below the watershed, is a primary source of drinking water . According to ECHO, Spokane Riverside Park WRF is located in an area with 10 State EJ Supplemental Indexes and eight Federal Supplemental Indexes greater than the 80th percen- tile within one mile of the facility, including wastewa- ter discharges at 95 (State) .165 According to the EPA EJScreen, of people living within one mile of Spokane Riverside Park WRF, 14% are people of color and 20% are low income .166 The NPDES permit167 for Spokane Riverside Park WRF does not include any limits on the amount of PFAS the facility discharges into the Spokane River and there are no pretreatment limits to control PFAS discharges to the WRF by industrial dischargers . Of the 14 permitted indus- trial users discharging wastewater to Spokane Riverside Park WRF, EPA’s PFAS Analytic Tools168 lists two as facili- ties “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemicals .”: Spokane Metal Finishing (Metal Coating) and Fairchild Airforce Base (National Defense) . The federal government has identified Fairchild Airforce Base (AFB) as one of the facilities that used aqueous film forming foam (AFFF) containing PFAS for firefighter training .169 There are likely additional unpermitted industrial dischargers contribut- ing PFAS to the WRF given that EPA’s PFAS Analytic Tools identifies 100 facilities located within the City of Spokane that operate in related sectors, including: • Airports • Chemical Mfg . • Electronics Industry • Fire Training • Furniture and Carpet • Industrial Gas • Metal Coating • Metal Machinery Mfg . • Mining and Refining • National Defense • Paints and Coatings • Paper Mills and Products • Petroleum • Plastics and Resins • Printing • Textiles and Leathers • Waste Management Washington Department of Ecology’s 2016 sampling study of Spokane Riverside Park WRF’s effluent revealed significant concentrations of PFAS . Specifically, the Department’s study detected concentration levels of total Perfluoroalkyl acids of 91 .8 ppt in the spring samples and 71 .4 ppt in the fall samples .170 For this project, Spokane Riverkeeper deployed PFASsive™ passive sampling devices immediately upstream and downstream from Spokane Riverside Park WRF's outfall from August 7, 2024 to September 11, 2024 . Samples of the Spokane River upstream and downstream from a Spokane Riverside Park WRF outfall contained multiple types of PFAS . However, the concentrations of four types of PFAS increased at the downstream site resulting in a total PFAS concentration increase of 4 .76 ppt or 383 .87% . For example, the concentration of PFHxA increased from 0 .54 ppt to 2 ppt (270 .37% increase) . Additional PFAS were also detected downstream at increased levels, including PFOA (1 .1 ppt), PFOS (2 .1 ppt), and PFHxS (0 .8 ppt) . PFOA and PFOS exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFHxS, and PFOS also exceeded the EWG health-based criteria . See Table 26 (p. 76). Table 25 | Spring Creek Upstream and Downstream from Biosolids Land Application Site Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)WI MCL (ppt)WI SW Quality– DW (ppt) WI SW Quality— All Waters (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 1.10 0.00 -1.10 -100.00%1000 PFPeA 0.00 0.00 0.00 0.00%1000 PFHxA 0.00 0.00 0.00 0.00%1000 PFHpA 0.00 0.00 0.00 0.00%1000 PFOA 0.00 0.00 0.00 0.00%4 0.0009 0.09 70 20 PFNA 0.00 0.00 0.00 0.00%10 0.006 PFDA 0.00 0.00 0.00 0.00%0.006 PFBS 0.00 0.00 0.00 0.00%400 2000 PFPeS 0.00 0.00 0.00 0.00%1 PFHxS 0.00 0.00 0.00 0.00%10 0.001 PFHpS 0.00 0.00 0.00 0.00%0.001 PFOS 0.00 0.00 0.00 0.00%4 0.06 0.3 70 8 FOSA 0.00 0.00 0.00 0.00%0.3 HFPO-DA (GenX)0.00 0.00 0.00 0.00%9 Total PFAS 1.1 0 -1.1 -100.00% Non-detect recorded as 0 WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 7574 Spokane Riverside Park WRF land applies biosolids at various locations in the Spokane River watershed . According to Spokane Riverside Park WRF’s 2023 Biosolids Facility Report, the facility produced 7,168 dry tons of Class B biosolids, all of which were land-applied in-state at eight agricultural sites in amounts ranging from 1 .69 tons/acre to 4 .07 tons/acre . The total measured acre- age of these sites was 2,613 .171 For this project, Spokane Riverkeeper deployed PFASsive™ passive sampling devices immediately upstream and downstream from multiple Spokane Riverside Park WRF land application sites—Eichmeyer Fields 3 and 5, Ingwaldson Fields 1 and 2, and Eckhart Fields 17 and 18—all of which are located along Dragoon Creek . The devices were deployed on August 7, 2024, and retrieved on September 11, 2024 . The downstream sampling site detected multiple types of PFAS . However, the upstream location only detected one type of PFAS, FOSA at 0 .63 ppt . At the downstream location, the concentrations of multiple types of PFAS increased significantly resulting in a total PFAS concentration increase of 32 .26 ppt—an increase of 5,120 .63% . For example, the concentration of PFPeA increased from a non-detect to 12 ppt, and the concentration of PFHxA increased from a non-detect to 7 .4 ppt . These results indicate that the Spokane Riverside Park WRF’s biosolids land application fields are likely a significant source of PFAS in Dragoon Creek, a tributary to the Little Spokane River . Additionally, the concentration of PFOA in the down- stream sample exceeded the draft HHWQC (Water + Organism), indicating the concentration exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . Specifically, in the downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 1 .4991 ppt . There are no national or state Clean Water Act surface water quality criteria for the protection of human health that apply to certain PFAS that were detected at elevated levels, including PFPeA, PFHxA, PFBS, PFBA, PFHpA, and PFHxS . FOSA—a type of PFAS that does not have any federal or state regulatory standards—exceeded EWG’s health-based criteria by 0 .58 ppt . PFOA and PFHxS also exceeded EWG’s health-based criteria . See Ta ble 27 (below). This evaluation indicates that Spokane Riverside Park WRF biosolids sites are likely contributing a significant amount of PFAS to Dragoon Creek and that multiple industrial dischargers are likely contributing to the WRF’s discharge of PFAS to the waterway . This pollution will likely continue to create significant risks to human health until PFAS pretreatment limits are placed on industrial sources of PFAS discharging into the WRF and PFAS limits are placed in Spokane Riverside Park WRFF’s NPDES permit, which will require installation of PFAS treat- ment technology, limits on biosolids land application, and a plan to safely manage PFAS removed during the treatment process . Table 26 | Spokane River Upstream and Downstream from Spokane Riverside Park WRF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)WA DW Action Level (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFHxA 0.54 2.00 1.46 270.37%1000 PFOA 0.00 1.10 1.10 n/a 4 0.0009 1.0991 0.09 1.01 10 PFHxS 0.00 0.80 0.80 n/a 10 0.001 0.799 65 PFOS 0.70 2.10 1.40 200.00%4 0.06 2.04 0.3 1.80 15 Total PFAS 1.24 6.00 4.76 383.87% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Table 27 | Dragoon Creek Upstream and Downstream from Biosolids Sites Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFPeA 0 12 12.00 n/a 1000 PFHxA 0 7.4 7.40 n/a 1000 PFBS 0 5.8 5.80 n/a 400 2000 PFBA 0 3.1 3.10 n/a 1000 PFHpA 0 1.5 1.50 n/a 1000 PFOA 0 1.5 1.50 n/a 4 0.0009 1.4991 0.09 1.41 PFHxS 0 0.71 0.71 n/a 10 0.001 0.709 FOSA 0.63 0.88 0.25 39.68%0.3 0.58 Total PFAS 0.63 32.89 32.26 5120.63% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Spokane Riverside Park WRF Biosolids Fields | Dragoon Creek PFAS Phase II Sampling Site Biosolids Land Application Fields WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 7776 Cape Fear Riverkeeper, Cape Fear and South Rivers, North Carolina Wastewater Treatment Plant and Biosolids Sites The Cross Creek WRF is a municipal wastewater treatment system that is owned and operated by the Fayetteville Public Works Commission and serves a population of approximately 100,500 residents .172 In addition, the facility handles wastewater from numerous industrial dischargers, including eight permitted Significant Industrial Users, two of which are Categorical Industrial Users .173 Cross Creek WRF discharges wastewater into the Cape Fear River at a monthly average design flow of 25 MGD . The Cape Fear River Basin, the largest in North Carolina, spans approximately 9,164 square miles, or about 16 .5% of the state’s total land area . Nearly one-third of North Carolina’s population resides in the basin . According to ECHO, Cross Creek WRF is located in an area with 12 State Supplemental EJ Indexes and 12 Federal Supplemental EJ Indexes greater than the 80th percentile within one mile of the facility, including wastewater discharges at 99 (State and Federal) .174 According to the EPA EJScreen, of people living within one mile of Cross Creek WRF, 89% are people of color, 77% are low income, and 9 .78% of households are on public assistance .175 The NPDES permit176 for Cross Creek WRF does not include any limits on the amount of PFAS the facility discharges into the Cape Fear River and no pretreatment limits to limit PFAS discharges to the WRF by industrial dischargers . Of the permitted industrial users discharg- ing wastewater to Cross Creek WRF, EPA’s PFAS Analytic Tools177 lists the following three as facilities “operat[ing] in sectors that have been identified as possibly handling, using, or releasing PFAS chemicals”: • Hexion Inc . — Fayetteville Facility (Plastics and Resins) • Goodyear Tire and Rubber Co . (Consumer Products) • Cumberland County Landfill (Waste Management) There are likely additional unpermitted industrial dis- chargers contributing PFAS to the WRF given that EPA’s PFAS Analytic Tools identifies 31 facilities located within the City of Fayetteville that operate in PFAS-related sec- tors including: • Airports • Chemical Mfg . • Consumer Products • Industrial Gas • Metal Coating • National Defense • Petroleum • Plastics and Resins • Waste Management In 2019, DEQ sampled Cross Creek WRF’s influent for PFAS . The sampling results showed the presence of 13 PFAS; five of which were detected at concentrations greater than 20 ppt: PFBA (max . 21 .3 ppt), PFHxS (max . 20 .4 ppt), PFHxA (max . 35 .5 ppt), PFPeA (max . 30 ppt), and PFOS (max . 28 .3 ppt) .178 For this project, Cape Fear Riverkeeper deployed PFASsive™ passive sampling devices immediately upstream and downstream from Cross Creek WRF’s outfall from September 5, 2024 to November 8, 2024 . Samples of the Cape Fear River upstream and downstream from Cross Creek WRF were contaminated with ten types of PFAS, and nine types of PFAS were detected at increased levels at the downstream site .179 PFAS were detected downstream at increased levels, including PFOA, PFBS, PFHxS, and PFOS . PFOA (8 .3 ppt) and PFOS (13 ppt) exceeded the MCL, rendering the surface water unsafe for drinking with- out advanced treatment, and exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFOS, PFNA, and PFHxS also exceeded the EWG health-based criteria . See Table 28 (p. 79). In addition to directly discharging wastewater into the Cape Fear River, the Fayetteville Public Works Commission is permitted to operate a Residuals Land Application Program to land apply wastewater treatment Class B residuals at various locations in the Cape Fear and Lumber River Basins .180 According to its 2023 Annual Report, which includes annual land application data from Cross Creek and Rockfish Creek WWTPs, Fayetteville land-applied 3,651 .02 dry tons of Class B residuals on 58 fields totalling 1,443 .93 acres during 2023 .181 The permits for these facili- ties do not contain any monitoring or limits on the amount of PFAS that can be present in the land-applied residuals . Fayetteville’s 2023 Annual Report182 also identifies the locations where the city land-applied these 3,651 .02 dry tons of residuals—of which 1,940 .35 dry tons were gen- erated by Cross Creek WRF . Several of Fayetteville’s sites with the greatest volumes of land application (exceeding three tons/acre) in 2023183 are located directly adjacent to the South River, a tributary to the Cape Fear River, near Autryville, North Carolina . These fields are traversed by ditches that channel runoff, shallow groundwater, and any pollutants directly into the South River . For this project, Cape Fear Riverkeeper deployed PFASsive™ passive sampling devices immediately upstream and downstream of Cross Creek WRF’s land application sites along the South River . These fields received 672 .66 tons of residuals from Cross Creek WRF in 2023 in amounts ranging from 1 .10 tons/ acre to 5 .07 tons/acre . The devices were deployed on August 27, 2024 . The downstream device was retrieved on November 8, 2024, and the upstream device was retrieved on January 10, 2025 . Cape Fear Riverkeeper also deployed a duplicate sampling device downstream of the land application site from August 27, 2024 to November 8, 2024 . Both upstream and downstream sampling sites detected multiple types of PFAS . However, the concentra- tions of all detected PFAS increased at the downstream site resulting in a total PFAS concentration increase of 20 .21 ppt (96 .28%) . For example, the concentration of PFBS increased from 2 .7 ppt to 5 .5 ppt (103 .7%) . Multiple other types of PFAS increased in downstream samples at levels ranging from 31 .58% to 86 .67% . These results indicate that the Cross Creek WRF’s residuals land appli- cation fields in the South River watershed are likely a significant source of PFAS in the South River . Downstream concentrations of PFAS demonstrate that the surface water at this location is unsafe for drinking without advanced treatment . For example, the concen- tration of PFOA at the downstream location was 5 .8 ppt, which is 1 .8 ppt greater than the MCL of 4 ppt, and the concentration of PFOS was 7 .5 ppt, which is 3 .5 ppt greater than the MCL of 4 ppt . The concentrations of PFOA and PFOS in the down- stream sample also exceeded the draft HHWQC (Water + Table 28 | Cape Fear River Upstream and Downstream from Fayetteville Cross Creek WRF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 5.00 5.40 0.40 7.41%1000 PFPeA 7.30 8.60 1.30 15.12%1000 PFHxA 5.70 6.70 1.00 14.93%1000 PFHpA 3.50 3.70 0.20 5.41%1000 PFOA 8.10 8.30 0.20 2.41%4 4.30 0.0009 8.2991 0.09 8.21 PFNA 1.10 1.10 0.00 0.00 10 0.006 1.094 PFBS 4.20 4.70 0.50 10.64%400 2000 PFPeS 0.93 0.94 0.01 1.06%1 PFHxS 5.10 5.30 0.20 3.77%10 0.001 5.299 PFOS 11.00 13.00 2.00 15.38%4 9.00 0.06 12.94 0.3 12.70 Total PFAS 51.93 57.74 5.81 10.06% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 7978 Organism), indicating that concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 5 .7991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 7 .44 ppt . There are no national or state Clean Water Act surface water quality criteria for the protection of human health that apply to certain PFAS that were detected at elevated levels, including PFPeA, PFBA, PFHxS, PFHpA, PFHxA, FOSA, PFNA, and HFPO-DA (Gen-X) . Additionally, FOSA—a type of PFAS that does not have any federal or state regulatory standards—exceeded EWG’s health-based criteria by 0 .56 ppt . PFOA, PFOS, PFNA, and PFHxS also exceeded EWG’s health-based criteria . See Ta ble 29 (below). This evaluation indicates that Cross Creek WRF’s land application sites are likely contributing a significant amount of PFAS to the South River and that multiple industrial dischargers are likely contributing to the WWTP’s discharge of PFAS to the waterway . This pollution will likely continue to create significant risks to human health until PFAS pretreatment limits are placed on industrial sources of PFAS discharging into the WWTP and PFAS limits are placed in the Cross Creek WRF’s NPDES permit, which will require installation of advanced treatment technology, limits on residuals land application, and a plan to safely manage PFAS removed during the treatment process . Cahaba Riverkeeper and Black Warrior Riverkeeper, Cahaba River and Cane Creek, Alabama Wastewater Treatment Plant and Biosolids Sites The Cahaba River WWTP is a municipal wastewater treat- ment system that is owned and operated by the Jefferson County Commission Environmental Services Department . This facility serves a population of 95,000 people184 and discharges wastewater into the Cahaba River at an average design flow of 12 MGD .185 According to ECHO, Cahaba River WWTP is located in an area with 10 State Supplemental EJ Indexes and nine Federal Supplement EJ Indexes greater than the state’s 80th percentile within one mile of the facility .186 According to the EPA EJScreen, of people living within one mile of Cahaba WRF, 65% are people of color and 34% are low income .187 The Jefferson County Environmental Services Department is authorized to receive discharges from numerous industrial dischargers pursuant to its Industrial Pretreatment Program, including 53 industrial facilities, of which 25 are permitted under the State Indirect Discharge (SID) program, and nine landfills .188 Because Jefferson County Environmental Services Department’s wastewater treatment and collection system consists of nine wastewa- ter treatment plants, including Cahaba River WWTP, it is unclear whether the facility receives discharges from any of these industrial users and, if so, to what extent . Although Cahaba River WWTP’s 2017 NPDES renewal applica- tion states that it is subject to an approved pretreatment program, the facility also states that it receives discharges from zero industrial users .189 The NPDES permit190 for Cahaba River WWTP does not include any limits on the amount of PFAS the facil- ity discharges into the Cahaba River, and there are no pretreatment limits to control PFAS discharges to the facility by industrial users . Of the 25 permitted industrial users discharging wastewater to the Jefferson County Environmental Services Department facilities, EPA’s PFAS Analytic Tools191 identifies the following 11 facilities as “operat[ing] in sectors that have been identified as possi- bly handling, using, or releasing PFAS chemicals”: • Amerex Corporation (Metal Coating and Chemical Mfg .) • Chevron Bulk Terminal Birmingham (Petroleum) • CRB (Plastics and Resins, and Textiles and Leather) • Hanna Steel (Metal Coating) • Kaiser Industries (Airports) • Kent Corporation (Metal Machinery Mfg .) • Max Coating (Metal Coating) • Nutec Metal Finishing, LLC (Metal Coating) • Precoat Metals (Metal Coating) • Progressive Metal Finishers, Inc . (Metal Coating) • Scholar Craft Products, Inc . (Metal Coating) EPA also identifies these landfills (Waste Management) as handling, using, or releasing PFAS, including: • Cedar Hill • Big Sky Solid Waste Facility • Eastern Area Landfill • Green Mountain • New Georgia Landfill • Pine View Landfill • Star Ridge • Willow Ridge Landfill In addition, 11 facilities (8 of which have separate NPDES permits) located in the Cities of Hoover, Irondale, and Vestavia Hills, areas serviced by Cahaba River WWTP, are also included on EPA’s list as potential PFAS-discharging facilities including: • TV Alabama (Airport) • City of Hoover (Waste Management) • Scholar Craft Products, Inc . (Metal Coating) • United Chair Irondale Plant (Metal Coating) • International Oil Corp . (Paints and Coatings) • Creative Polymer Solutions, LLC (Plastics and Resins) • Eastwood Mobile Home Village (Waste Management) • EWTN WWTP (Waste Management) • Irondale WWTF (Waste Management) • Liberty Park WRRF (Waste Management) • Cahaba River WRF (Waste Management), the facility sampled for purposes of this report For this project, Cahaba Riverkeeper deployed PFASsive™ passive sampling devices immediately upstream and downstream from Cahaba River WWTP's outfall from August 22, 2024 to September 18, 2024 . Samples taken upstream and downstream from Cahaba Table 29 | South River Upstream and Downstream from Biosolids Site Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Downstream Duplicate Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFPeA 0 4.2 4.8 4.20 n/a 1000 PFBA 3.9 6.7 6.2 2.80 71.79%1000 PFBS 2.7 5.5 5.1 2.80 103.70%400 2000 PFOA 3.3 5.8 5.8 2.50 75.76%4 1.8 0.0009 5.7991 0.09 5.71 PFHxS 0 2.4 2.2 2.40 n/a 10 0.001 2.399 PFOS 5.7 7.5 6.7 1.80 31.58%4 3.5 0.06 7.44 0.3 7.2 PFHpA 1.5 2.8 2.8 1.30 86.67%1000 PFHxA 2.2 3.1 3.2 0.90 40.91%1000 FOSA 0 0.86 0.62 0.86 n/a 0.3 0.56 PFNA 1 1.4 1.3 0.40 40.00%10 0.006 1.394 HFPO-DA (GenX)0.69 0.94 0.84 0.25 36.23%10 9 Total PFAS 20.99 41.2 39.56 20.21 96.28% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Fayetteville Cross Creek Biosolids Fields | South River PFAS Phase II Sampling Site Biosolids Land Application Fields WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 8180 River WWTP outfalls were contaminated with multiple types of PFAS, and six types of PFAS were detected at increased concentrations at the downstream site .192 PFPeA increased most significantly at the downstream site from 7 .3 ppt to 10 ppt (36 .99%) . The total PFAS concentration increased by 3 .46 ppt or 9 .09% . At the downstream site, PFOA (4 .9 ppt) exceeded the MCL, rendering the surface water unsafe for drinking water without advanced treat- ment . PFOA and PFOS also exceeded the draft HHWQC (Water + Organism) at the downstream site, indicating the concentration exceeded the level EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . Additionally, numerous PFAS significantly exceeded EWG’s health-based criteria, includ- ing PFOA, PFNA, PFHxS, and PFOS . See Ta ble 30 (above). In 2024, Cahaba River WWTP generated 4,664 dry tons of biosolids . However, the facility has not produced biosolids for land application since October 2020 .193 Its current process for disposing of biosolids is to pump them, as waste activated biosolids, to the Al Seier Pump Station, where they are mixed with wastewater and sent to the Valley Creek WRF for full treatment . From Valley Creek,194 the biosolids are authorized to be land-applied at a 241-acre mine reclamation site, called the Flat Top Land Application Site, as well as a 1,000-acre agricultural land application site, called the Beltona Land Reclamation Site . The Beltona Land Reclamation Site, which is located in the Cane Creek watershed (in Black Warrior Riverkeeper’s watershed), is used to grow bermuda grass for erosion control . For this project, Cahaba Riverkeeper and Black Warrior Riverkeeper deployed PFASsive™ passive sampling devices and duplicate sampling devices immediately upstream and downstream of the Beltona Land Reclamation Site in Cane Creek to determine its contribution of PFAS contamination to that waterway . The devices were deployed from August 20, 2024 to September 17, 2024 . Both upstream and downstream sampling sites detected multiple types of PFAS . However, the concentrations of eight types of PFAS increased at the downstream sites, resulting in a total PFAS concentration increase of 28 .54 ppt—an increase of 201 .84%—in the pri- mary samples,195 and an increase of 18 .12 ppt (140 .47%) in the duplicate samples . PFPeA and PFBA were detected at the highest concentrations—both 11 ppt . In the primary and duplicate samples, the concentration of PFHpA increased from 0 .54 ppt to 1 .7 ppt (214 .81%) and a non-detect to 1 .4 ppt, respectively . The concentration of PFHxA in the primary and duplicate samples increased from 1 .2 ppt to 4 .2 ppt (250%) and 1 ppt to 3 .1 ppt (210%) . Also, the concentration of PFBA in the primary and dupli- cate samples increased from 3 .8 ppt to 11 ppt (189 .47%) and 2 .7 ppt to 6 .4 ppt (137 .04%) . Multiple other types of PFAS increased in downstream samples at levels rang- ing from 52 .63% to 127 .78% in the primary sample and 34 .15% to 126 .67% in the duplicate samples . These results indicate that the Cahaba River/Valley Creek WWTPs’ bio- solids land application site is likely a significant source of PFAS in Cane Creek, a tributary to the Locust Fork, which is a tributary to the Black Warrior River . The concentration of regulated PFAS increased down- stream from the biosolids land application field, including PFOS, PFOA, and PFNA . Downstream concentrations of PFAS demonstrate that the surface water at this loca- tion is unsafe for drinking without advanced treatment . For example, the downstream concentration of PFOA was 4 .1 ppt, which is 0 .1 ppt greater than the MCL, and the concentration of PFOS was 5 .8 ppt, which is 1 .8 ppt greater than the MCL . The concentrations of PFOA and PFOS in the down- stream sample also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 4 .0991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 5 .74 ppt . There are no national or state Clean Water Act surface water quality criteria for the protection of human health that apply to certain PFAS that were detected at elevated levels, including PFPeA, PFBA, PFHxA, PFHpA, and PFNA . However, PFOA, PFOS, PFNA, and PFHxS exceeded EWG’s health-based criteria . See Ta ble 31 (below). This evaluation indicates that Cahaba River WWTP’s land application site is likely contributing a significant amount of PFAS to Cane Creek and that multiple industrial dis- chargers to the facility are likely contributing to the WWTP’s discharge of PFAS to the waterway . This pollution will likely continue to create significant risks to human health until PFAS pretreatment limits are placed on industrial sources of PFAS discharging into the facility and PFAS limits are placed in the Cahaba River WWTP’s NPDES permit, which will require installation of PFAS treatment technology, limits on biosolids land application, and a plan to safely manage PFAS removed during the treatment process . Table 30 | Cahaba River Upstream and Downstream from Cahaba River WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 5.20 5.20 0.00 0.00 1000 PFPeA 7.30 10.00 2.70 36.99%1000 PFHxA 5.40 6.40 1.00 18.52%1000 PFHpA 1.70 1.90 0.20 11.76%1000 PFOA 4.60 4.90 0.30 6.52%4 0.90 0.0009 4.8991 0.09 4.81 PFNA 0.85 0.73 -0.12 0.14%10 0.006 0.724 PFDA 0.52 0.00 -0.52 -100.00%0.006 PFBS 6.00 6.40 0.40 6.67%400 2000 PFHxS 1.30 1.50 0.20 15.38%10 0.001 1.499 PFOS 5.20 4.50 -0.70 -13.46%4 0.50 0.06 4.44 0.3 4.20 Total PFAS 38.07 41.53 3.46 9.09% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Table 31 | Cane Creek Upstream and Downstream from Biosolids Site Analyte Sample (ppt)Duplicate Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFPeA 0 11 11 n/a 0 6.1 6.1 n/a 1000 PFBA 3.8 11 7.2 189.47%2.7 6.4 3.7 137.04%1000 PFHxA 1.2 4.2 3 250.00%1 3.1 2.1 210.00%1000 PFOA 1.8 4.1 2.3 127.78%1.5 3.4 1.9 126.67%4 0.1 0.0009 4.0991 0.09 4.01 PFOS 3.8 5.8 2 52.63%4.1 5.5 1.4 34.15%4 1.8 0.06 5.74 0.3 5.5 PFBS 1.4 2.7 1.3 92.86%1.4 2.5 1.1 78.57%400 2000 PFHpA 0.54 1.7 1.16 214.81%0 1.4 1.4 n/a 1000 PFNA 0 0.68 0.68 n/a 0 0.62 0.62 n/a 10 0.006 0.674 PFHxS 1.6 1.5 -0.1 -6.25%2.2 2 -0.2 -9.09%10 0.001 1.499 Total PFAS 14.14 42.68 28.54 201.84%12.9 31.02 18.12 140.47% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Beltona Land Reclamation Site | Cane Creek PFAS Phase II Sampling Site Biosolids Land Application Fields WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 8382 SAMPLING RESULTS BY WATERKEEPER GROUP WATERSHED196 Bayou City Waterkeeper, Hunting Bayou, Texas Wastewater Treatment Plant Site The Hunting Bayou watershed spans the city limits of Houston, Galena Park, and Jacinto City, with an estimated population of 75,627 . The Homestead WWTP, a munic- ipal wastewater treatment facility, serves 7,961 people and discharges treated wastewater to Hunting Bayou .197 Within one mile of the facility, 97% of residents are people of color, and 68% are low-income . EPA has identified approximately 1,405 potential PFAS-discharging facilities within Houston .198 Samples taken upstream and downstream from a WWTP outfall on Hunting Bayou were contaminated with multiple types of PFAS, and seven types of PFAS were detected at increased concentrations at the downstream site . Regulated PFAS were detected downstream from the WWTP, including PFOA, PFNA, PFHxS, and PFOS .199 While PFAS levels increased downstream from the WWTP, the difference between upstream and downstream concentrations was not significant for most PFAS with the exception of PFHxA, which increased by 4 .2 ppt (61 .76%) . However, the total PFAS concentration increased by 5 .7 ppt (9 .87%) . The PFAS contamination, both upstream and down- stream, has rendered the surface water unsafe for drinking without advanced treatment, with PFOS (4 ppt) at the level of the MCL and PFOS exceeding the MCL by 8 ppt . PFOS and PFOA also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . Multiple PFAS exceeded EWG’s health-based criteria . See Ta ble 32 (below). Chattahoochee Riverkeeper, Chattahoochee River, Georgia Wastewater Treatment Plant Site The Chattahoochee River Basin, also known as the Apalachicola-Chattahoochee-Flint basin, covers an area of 8,770 square miles . The Chattahoochee River flows south- west for 434 miles, starting in the southern Appalachian Mountains, passing through the Atlanta metropolitan area, and ending at Lake Seminole . The river provides 70 percent of Atlanta’s drinking water . The City of Atlanta’s R .M . Clayton WRC, Cobb County’s R .L . Sutton WRF, and the West Area WQCF discharge treated wastewater into the Chattahoochee River .200 Of the people living within one mile of these facilities, 42% are people of color and 17% are low-income . EPA has identified approximately 290 potential PFAS-discharging facilities within the City of Atlanta, which is served by multiple wastewater treatment plants .201 Samples taken upstream and downstream from the facilities’ outfalls to the Chattahoochee River were con- taminated with multiple types of PFAS . Nine types of PFAS were detected at elevated levels downstream from the discharge points, including PFPeA at 6 .1 ppt (74 .29% increase) and PFTeA at 4 .1 ppt (upstream sample was non-detect) . The total PFAS concentration increased by 15 .58 ppt (88 .93%) . Federally regulated PFAS were detected downstream at increased levels, including PFBS and PFOA . PFOA and PFOS exceeded the draft HHWQC (Water + Organism), indicating the concentra- tions exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFDoA, PFTeA, PFHxS, PFOS, and PFMPA also exceeded the EWG health-based criteria . See Ta ble 33 (below). Table 32 | Hunting Bayou Upstream and Downstream from Homestead WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 6.30 6.20 -0.10 -1.59%1000 PFPeA 8.70 9.30 0.60 6.90%1000 PFHxA 6.80 11.00 4.20 61.76%1000 PFHpA 3.70 3.40 -0.30 -8.11%1000 PFOA 3.70 4.00 0.30 8.11%4 0.0009 3.9991 0.09 3.91 PFNA 1.20 1.30 0.10 8.33%10 0.006 1.29 PFDA 0.55 0.64 0.09 16.36%0.006 0.63 PFBS 9.40 11.00 1.60 17.02%400 2000 PFPeS 0.72 0.63 -0.09 -12.50%1 PFHxS 4.70 4.00 -0.70 -14.89%10 0.001 4.00 PFOS 11.00 12.00 1.00 9.09%4 8.00 0.06 11.94 0.3 11.70 6:2 FTS 1.00 0.00 -1.00 -100.00%1 Total PFAS 57.77 63.47 5.70 9.87% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Table 33 | Chattahoochee River Upstream and Downstream from The City of Atlanta’s R .M Clayton WRC, Cobb County’s R .L . Sutton WRF, and the West Area WQCF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 1.6 2.1 0.5 31.25%1000 PFPeA 3.50 6.10 2.60 74.29%1000 PFHxA 3.20 4.60 1.40 43.75%1000 PFHpA 0.82 1.50 0.68 82.93%1000 PFOA 2.70 2.80 0.10 3.70%4 0.0009 2.7991 0.09 2.71 PFDoA 0.00 1.20 1.20 n/a 0.006 1.194 PFTeA 0.00 4.10 4.10 n/a 0.006 4.094 PFBS 1.30 4.30 3.00 230.77%400 2000 PFHxS 1.80 1.70 -0.10 -5.56%10 0.001 1.699 PFOS 2.60 2.60 0.00 0.00%4 0.06 2.54 0.3 2.30 PFMPA 0.00 2.10 2.10 n/a 1 1.10 Total PFAS 17.52 33.10 15.58 88.93% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 8584 Coosa Riverkeeper, Big Wills Creek and Whippoorwill Creek, Alabama Wastewater Treatment Plant and Biosolids Sites The Coosa River Basin spans more than 10,000 square miles and flows over 280 miles from northwestern Georgia to central Alabama . The Lower Coosa River Basin is home to up to 46 federally protected species, and is consid- ered one of the most biodiverse ecosystems in the world . Big Wills Creek is a tributary to the Coosa River and Whippoorwill Creek is a tributary to the Locust Fork River in the Black Warrior River watershed . The Rainbow City WWTP is a municipal facility that discharges treated waste- water to Big Wills Creek .202 The facility does not receive discharges from significant industrial users . Of the people living within one mile of the Rainbow City WWTP, 24% are people of color and 38% are low-income . The Rainbow City WWTP is a municipal facility that produces approximately 1,400 lbs/day of Class B bio- solids, which is stored in a biosolids lagoon . Since 2023, the plant has contracted with Denali Water Systems to transport biosolids to the Dennis Burton Farm in Altoona, Alabama, where it is land-applied as fertilizer for growing crops in the Whippoorwill Creek watershed .203 According to Denali’s nutrient management plan, about 125 acres of land receive the plant’s biosolids each year . Samples of Big Wills Creek upstream and downstream from a Rainbow City WWTP outfall contained multiple types of PFAS .204 No significant increases were observed between upstream and downstream samples, with the exception of FOSA (non-detect to 1 .6 ppt increase) . Numerous PFAS decreased in the downstream sample, as did the total PFAS concentration by 2 .33 ppt (15 .49%) . These results could have been influenced by factors such as backflow from the Coosa River, season, precipi- tation, discharge schedules, and leachate contributions . At the downstream site, PFOA and PFOS exceeded the draft HHWQC (Water + Organism), indicating the con- centrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFNA, PFHxS, PFOS, and FOSA also exceeded the EWG health-based criteria . See Ta ble 34 (below). The designated upstream and downstream sam- pling sites in Whippoorwill Creek near the Rainbow City WWTP’s biosolids land application site, which is located in the Black Warrior River watershed, also contained PFAS . Due to sampling location constraints, the upstream sam- pling site was adjacent to one of the biosolids application fields . PFAS decreased significantly between upstream and downstream samples, with many downstream sam- ples showing non-detect for multiple PFAS . The total PFAS concentration also decreased by 11 .75 ppt (83 .81%) . At the upstream site, PFOS (5 .6 ppt), exceeded the MCL, rendering the surface water at this location unsafe for drinking without advanced treatment . At the upstream and downstream sites, PFOA and PFOS exceeded the draft HHWQC (Water + Organism), indicating the concen- trations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA and PFOS also exceeded the EWG health-based criteria at the downstream site . See Ta ble 35 (below). Table 34 | Big Wills Creek Upstream and Downstream from Rainbow City WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 1.80 1.90 0.10 5.56%1000 PFPeA 2.70 0.00 -2.70 -100.00% PFHxA 2.70 2.60 -0.10 -3.70%1000 PFHpA 0.96 0.95 -0.01 -1.04%1000 PFOA 2.00 2.20 0.20 10.00%4 0.0009 2.1991 0.09 2.11 PFNA 0.58 0.54 -0.04 -6.90%10 0.006 0.534 PFDA 0.65 0.00 -0.65 -100.00%0.006 PFBS 0.82 0.58 -0.24 -29.27%400 2000 PFHxS 0.63 0.64 0.01 1.59%10 0.001 0.639 PFOS 2.20 1.70 -0.50 -22.73%4 0.06 1.64 0.3 1.40 FOSA 0.00 1.60 1.60 n/a 0.3 1.30 Total PFAS 15.04 12.71 -2.33 -15.49% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Table 35 | Whippoorwill Creek Upstream and Downstream from Biosolids Land Application Sites Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 1.8 0.00 -1.80 -100.00%1000 PFHxA 0.86 0.00 -0.86 -100.00%1000 PFHpA 0.72 0.00 -0.72 -100.00%1000 PFOA 2.4 0.77 -1.63 -67.92%4 0.0009 0.7691 0.09 0.68 PFBS 1.7 0.00 -1.70 -100.00%400 2000 PFHxS 0.94 0.00 -0.94 -100.00%10 0.001 PFOS 5.6 1.5 -4.10 -73.21%4 0.06 1.44 0.3 1.20 Total PFAS 14.02 2.27 -11.75 -83.81% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 8786 Hackensack Riverkeeper, Ramapo River, New York/New Jersey Wastewater Treatment Plant Site The Ramapo River Basin, located in southeastern New York State and northeastern New Jersey, covers approx- imately 935 square miles and is a major tributary of the Passaic River . Sampling was conducted on the Ramapo River upstream and downstream from two municipal WWTPs that discharge to the Ramapo River: the Suffern (V) STP and the Western Ramapo WWTP .205 The Suffern (V) STP serves a population of 13,000 people . Within one mile of the Western Ramapo WWTP, 56% of residents are people of color and 27% are low-income . New York State has also designated this area as a Disadvantaged Community .206 The EPA has identified eight poten- tial PFAS-discharging facilities within the Cities of Suffern and Hillburn .207 Samples of the Ramapo River upstream and down- stream from the WWTPs’ outfalls contained multiple types of PFAS .208 At the downstream site in Mahwah, New Jersey just across the border from Suffern, New York, five types of PFAS were detected at elevated levels, including PFHxA at 10 ppt (2 .5 ppt increase), PFHxS at 3 .5 ppt (non-de- tect at upstream site), and PFBS at 2 .5 ppt (non-detect at upstream site) . The total PFAS concentration increased by 10 .10 ppt (45 .7%) . Federally regulated PFAS were detected downstream at increased levels, including PFOA (6 .7 ppt), PFBS, PFOS (4 .7 ppt), and PFHxS . PFOA and PFOS exceeded the MCLs at the downstream site, rendering the surface water at this location unsafe for drinking without advanced treatment . PFOA and PFOS also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . The PFOS concentration in the downstream sample exceeded New York’s water quality guidance values for protection of human health in raw source water209 and PFOA, PFOS, and PFHxS also exceeded the EWG health-based criteria . See Ta ble 36 (below). James Riverkeeper, Appomattox River and Old Town Creek, Virginia Wastewater Treatment Plant and Biosolids Sites The James River, Virginia’s largest river, flows 340 miles and connects to 25,000 miles of tributaries, including the Appomattox River . Its watershed spans approxi- mately 10,000 square miles, making up nearly a quarter of the state . About one-third of Virginians live within this watershed . Within one mile of the South Central WWTP,210 a wastewater treatment system serving five localities and discharging effluent to the Appomattox River, 56% are people of color and 33% are low income . EPA has identified 29 potential PFAS-discharging facilities in Petersburg .211 Samples of the Appomattox River upstream and downstream from a South Central WWTP outfall contained multiple types of PFAS . However, the concentrations of several of PFAS increased slightly at the downstream site resulting in a total PFAS concentration increase of 0 .5 ppt—an increase of 2 .37% . PFOA (2 .6 ppt) and PFOS (2 .6 ppt) were detected in downstream samples at levels that exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general pop- ulation from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFOS, PFNA, and PFHxS also exceeded the EWG health-based criteria . See Ta ble 37 (below). South Central WWTP’s method for disposing of its biosolids is through land application .212 The facility pro- duces Class B biosolids, which it prepares for land appli- cation through dewatering followed by lime stabilization . According to South Central WWTP’s Biosolids Facility Report,213 the facility produced and land applied 3,426 dry metric tons of biosolids in 2023, however, the land appli- cation is handled by Synagro Central, LLC, which sources biosolids for land application from multiple WWTPs .214 For purposes of this project, James Riverkeeper conducted PFAS sampling downstream from a Synagro biosolids land application field, VA-CH-00004-0-0010, located in the Old Town Creek watershed .215 Table 36 | Ramapo River Upstream and Downstream from WWTP and STP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)NY MCL (ppt)State Ambient WQ for HH (DW) (ppt) Upstream Downstream Change % Change Upstream (August)Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 0.00 0.00 0.00 0.00%3.30 1000 PFPeA 5.40 4.80 -0.60 -11.11%9.10 1000 PFHxA 7.50 10.00 2.50 33.33%5.90 1000 PFHpA 0.00 0.00 0.00 0.00%2.20 1000 PFOA 6.10 6.70 0.60 9.84%5.20 4 2.70 0.0009 6.6991 0.09 6.61 10 6.7 PFNA 0.00 0.00 0.00 0.00%1.60 10 0.006 PFUnA 0.00 0.00 0.00 0.00%0.97 0.006 PFBS 0.00 2.50 2.50 n/a 1.30 400 2000 PFHxS 0.00 3.50 3.50 n/a 1.00 10 0.001 3.50 PFOS 3.10 4.70 1.60 51.61%3.90 4 0.70 0.06 4.64 0.3 4.40 10 2.7 2.00 FOSA 0.00 0.00 0.00 0.00%0.56 0.3 Total PFAS 22.10 32.20 10.10 45.70%35.03 Non-detect recorded as 0 Downstream Increase Exceed criteria levels Table 37 | Appomattox River Upstream and Downstream from South Central WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 5.80 4.50 -1.30 -22.41%1000 PFPeA 3.50 4.40 0.90 25.71%1000 PFHxA 2.90 2.80 -0.10 -3.45%1000 PFHpA 1.20 1.10 -0.10 -8.33%1000 PFOA 2.40 2.60 0.20 8.33%4 0.0009 2.5991 0.09 2.51 PFNA 0.00 0.75 0.75 n/a 10 0.006 0.744 PFBS 2.10 2.30 0.20 9.52%400 2000 PFHxS 0.57 0.56 -0.01 -1.75%10 0.001 0.559 PFOS 2.10 2.60 0.50 23.81%4 0.06 2.54 0.3 2.30 PFMPA 0.54 0.00 -0.54 -100.00%1 Total PFAS 21.11 21.61 0.50 2.37% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 8988 Samples of Old Town Creek taken downstream from the biosolids land application site detected multiple types of PFAS . The PFAS detected at the highest con- centrations were PFOA (3 .9 ppt) and PFOS (3 .1 ppt) . The concentrations of PFOA and PFOS in the sample taken downstream from the land application site also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . In the downstream sample, PFOA exceeded the draft HHWQC (Water + Organism) of 0 .0009 ppt by 3 .8991 ppt, and PFOS exceeded the 0 .06 ppt criteria by 3 .04 ppt . Additionally, PFHxS, PFOA, and PFOS exceeded EWG’s health-based criteria . See Ta ble 38 (below). Long Island Soundkeeper, Naugatuck River, Connecticut Wastewater Treatment Plant Site The Naugatuck River Watershed spans 311 square miles and drains into the Naugatuck River, the only major river entirely within Connecticut and the largest tributary of the Housatonic River . Waterbury WPCF is a wastewater treat- ment system that serves approximately 125,000 residents of Waterbury and three other communities and handles wastewater from industrial dischargers .216 Within one mile of the Waterbury WPCF, 44% of residents are people of color and 29% are low-income . The WWTP discharges treated wastewater to the Naugatuck River . EPA has identified 38 active PFAS-discharging facilities within the City of Waterbury .217 Samples of the Naugatuck River upstream and down- stream from Waterbury WPCF outfalls contained multiple types of PFAS . However, the concentrations of seven types of PFAS increased at the downstream site resulting in a total PFAS concentration increase of 4 .9 ppt—an increase of 11 .78% . For example, the concentration of PFHxA increased from 7 .1 ppt to 8 .9 ppt (25 .35%) . Federally regulated PFAS were also detected down- stream at increased levels, including PFOS (8 .3 ppt), PFBS (3 .1 ppt), and PFHxS (1 .7 ppt) . However, the concentration of PFOA decreased slightly from 8 .1 ppt to 7 .8 ppt (3 .7% decrease) . PFOA exceeded the MCL by 3 .8 ppt and PFOS exceeded the MCL by 4 .3 ppt, rendering the surface water at this location unsafe for drinking without advanced treat- ment . PFOA and PFOS also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFNA, PFHxS, and PFOS also exceeded the EWG health-based criteria . See Ta ble 39 (below). Table 38 | Old Town Creek Downstream from Biosolids Land Application Field Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Downstream Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 1.3 1000 PFPeA 1.7 1000 PFHxA 1.7 1000 PFHpA 0.81 1000 PFOA 3.9 4 0.0009 3.8991 0.09 3.81 PFBS 1.3 400 2000 PFHxS 1.5 10 0.001 1.499 PFOS 3.1 4 0.06 3.04 0.3 2.80 Total PFAS 15.31 Non-detect recorded as 0 Exceed criteria levels Table 39 | Naugatuck River Upstream and Downstream from Waterbury WPCF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)State DW Action Level (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 3.60 4.80 1.20 33.33%1000 1800 PFPeA 6.90 8.10 1.20 17.39%1000 PFHxA 7.10 8.90 1.80 25.35%1000 240 PFHpA 2.50 2.60 0.10 4.00%1000 PFOA 8.10 7.80 -0.30 -3.70%4 3.80 0.0009 7.7991 0.09 7.71 16 PFNA 1.50 1.20 -0.30 -20.00%10 0.006 1.194 12 PFBS 2.70 3.10 0.40 14.81%400 2000 760 PFHxS 1.60 1.70 0.10 6.25%10 0.001 1.699 49 PFOS 7.60 8.30 0.70 9.21%4 4.30 0.06 8.24 0.3 8.00 10 Total PFAS 41.60 46.50 4.90 11.78% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 9190 Los Angeles Waterkeeper, Los Angeles River, California Wastewater Treatment Plant Site The Los Angeles (LA) River Watershed spans 834 square miles, with the river stretching 51 miles from its headwaters in the Angeles National Forest to the Pacific Ocean in Long Beach . The LA-Glendale WRP is a municipal wastewater treatment system that is co-owned by the Cities of Los Angeles and Glendale, and operated by LA Sanitation, that serves a population of approximately 434,000 residents and handles wastewater from multiple industrial discharg- ers .218 Within one mile of the LA River, there are 17 cities, 23 City of LA neighborhoods, and four unincorporated communities, and nearly 1,000,000 residents .219 Within one mile of the LA-Glendale WRF, 54% of the population are people of color and 39% are low-income . Data for indus- trial discharges from the LA-Glendale WRF are aggregated with those from three other reclamation plants . In 2021, these four facilities received discharges from 166 permitted industrial users . EPA has identified 23 facilities in the City of Glendale alone as potential sources of PFAS discharges .220 Samples of the LA River upstream and downstream from the LA-Glendale WRF outfall contained multiple types of PFAS . However, the concentrations of five types of PFAS increased at the downstream site resulting in a total PFAS concentration increase of 6 .01 ppt—an increase of 8 .61% . For example, the concentration of PFPeA increased from 12 ppt to 20 ppt (66 .67% increase) and the concentration of PFBA increased from 7 .8 ppt to 9 .8 ppt (25 .64% increase) . Federally regulated PFAS were also detected down- stream but at decreased concentrations, including PFOA (1 .04% decrease) and PFOS (13 .24% decrease) . However, in the downstream sample, PFOA (9 .5 ppt) exceeded the MCL by 5 .5 ppt and PFOS (5 .9 ppt) exceeded the MCL by 1 .9 ppt, indicating the surface water at this loca- tion is unsafe for drinking without advanced treatment . Additionally, PFOA exceeded the California Public Health Goal of 0 .007 ppt by 9 .493 ppt and PFOS exceeded the California Public Health Goal of 1 ppt by 4 .9 ppt .221 PFOA and PFOS also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody, and PFOA, PFOS, PFDA, and PFHxS exceeded the EWG health- based criteria . See Ta ble 40 (below). Narragansett Bay Riverkeeper, Pawtuxet River, Rhode Island Wastewater Treatment Plant Site The Pawtuxet River Watershed is the second largest water- shed in Rhode Island, covering 231 square miles and it is home to approximately 235,000 residents . The Cranston WPCF is a municipal wastewater treatment system serving around 73,200 residents .222 Within one mile of the Cranston WPCF, 25% of residents are people of color and 18% are low-income . The facility discharges treated wastewater to the Pawtuxet River . EPA has identified 42 potential PFAS- discharging facilities within Cranston .223 Samples of the Pawtuxet River upstream and down- stream from WPCF outfalls contained multiple types of PFAS . The concentrations of five types of PFAS slightly increased at the downstream site . However, there was not a significant difference between the two sites, with the downstream site showing a total PFAS concentration increase of 0 .6 ppt—an increase of 1 .57% . The PFOS con- centration decreased slightly by 0 .2 ppt . Federally regulated PFAS were detected downstream, including PFOA (7 .7 ppt), PFBS (1 .5 ppt), PFOS (4 .3 ppt), PFNA (2 .1 ppt), and PFHxS (2 .3 ppt) . PFOA exceeded the MCL by 3 .7 ppt and PFOS exceeded the MCL 0 .3 ppt, rendering the surface water at this location unsafe for drinking without advanced treatment . However, the PFOA concentration decreased in the downstream duplicate sample and the upstream duplicate concentration was also higher than the downstream primary sample con- centration by 0 .1 ppt . PFOA and PFOS also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody, and PFOA, PFNA, PFHxS, and PFOS exceeded the EWG health-based criteria . See Ta ble 41 (below). Table 40 | Los Angeles River Upstream and Downstream from LA-Glendale WRF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)CA Public Health Goal (ppt) CA Notification Level (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 7.80 9.80 2.00 25.64%1000 PFPeA 12.00 20.00 8.00 66.67%1000 PFHxA 19.00 20.00 1.00 5.26%1000 PFHpA 3.10 3.30 0.20 6.45%1000 PFOA 9.60 9.50 -0.10 -1.04%4 5.50 0.0009 9.4991 0.09 9.41 0.007 9.493 PFNA 1.10 0.00 -1.10 -100.00%10 0.006 PFDA 2.00 2.10 0.10 5.00%0.006 2.094 PFBS 3.70 2.50 -1.20 -32.43%400 2000 500 PFPeS 0.57 0.00 -0.57 -100.00%1 PFHxS 3.50 2.70 -0.80 -22.86%10 0.001 2.699 3 PFOS 6.80 5.90 -0.90 -13.24%4 1.90 0.06 5.84 0.3 5.60 1 4.90 NEtFOSAA 0.62 0.00 -0.62 -100.00%1 Total PFAS 69.79 75.80 6.01 8.61% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Table 41 | Pawtuxet River Upstream and Downstream from Cranston WPCF Analyte Sample (ppt)Duplicate Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)RI MCL (ppt)RI SWQ Action Level (ppt) Upstream Downstream Change % Change Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 3.20 3.10 -0.10 -3.13%3.30 3.20 -0.10 -3.03%1000 Sum of 8 => 70 pptPFPeA 5.50 5.70 0.20 3.64%5.40 5.30 -0.10 -1.85%1000 PFHxA 7.40 7.20 -0.20 -2.70%6.70 7.30 0.60 8.96%1000 PFHpA 4.80 4.90 0.10 2.08%4.60 4.90 0.30 6.52%1000 PFOA 7.10 7.70 0.60 8.45%7.80 7.50 -0.30 -3.85%4 3.70 0.0009 7.6991 0.09 7.61 PFNA 2.00 2.10 0.10 5.00%2.00 1.90 -0.10 -5.00%10 0.006 2.094 PFBS 1.50 1.50 0.00 0.00%1.70 1.50 -0.20 -11.76%400 2000 PFHxS 2.20 2.30 0.10 4.55%2.20 2.30 0.10 4.55%10 0.001 2.299 PFOS 4.50 4.30 -0.20 -4.44%4.70 4.30 -0.40 -8.51%4 0.30 0.06 4.24 0.3 4.00 Total PFAS 38.20 38.80 0.60 1.57%38.40 38.20 -0.20 -0.52% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 9392 Pearl Riverkeeper, Pearl River, Mississippi Wastewater Treatment Plant and Biosolids Sites The Pearl River Basin spans 8,760 square miles in Central and Southern Mississippi and three Louisiana parishes, eventually draining in the Mississippi Sound, Lake Borgne, and the Gulf of Mexico . It is home to nearly one million people, more than one-third of Mississippi’s population . There are three WWTPs located near one or more of the locations selected for sampling by Pearl Riverkeeper— Jackson POTW, Savannah Street, West Rankin Utility Authority WWTF, and Jackson POTW, Trahon and Big Creek .224 Within one mile of the Jackson POTW, Savanna Street, 80% of residents are people of color and 60% are low-income . The EPA has identified 50 potential PFAS- discharging facilities within the City of Jackson .225 Pearl Riverkeeper sampled upstream and downstream from two separate outfalls into the Pearl River from Jackson POTW, Savannah Street and West Rankin Utility Authority WWTF . These two outfalls are approximately 1 .6 river miles apart . A tributary stream also flows into the Pearl River between the upstream and downstream sam- pling locations . The upstream sampler was not recovered so no results are available for that location . The sample from the downstream location contained eight types of PFAS . Overall, the total PFAS concentration at the down- stream location was 20 .71 ppt . PFHxA (4 .4 ppt) and PFBA (3 .6 ppt) were detected at the highest concentrations . The federally regulated PFAS detected downstream included PFOA (2 .9 ppt), PFBS (3 ppt), PFOS (3 .5 ppt), PFNA (0 .71 ppt), and PFHxS (1 .3 ppt) . PFOA and PFOS exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody, and PFOA, PFNA, PFHxS, and PFOS exceeded the EWG health-based criteria . See Table 42 (below) Pearl Riverkeeper also collected additional samples at two locations further downstream . One sampling site was located upstream and the other sampling site was located downstream from where Big Creek enters the Pearl River . One or more of Jackson POTW’s biosolids application fields are located in the Big Creek watershed roughly 1 .5 – 2 .0 miles from the confluence of Big Creek and the Pearl River . Jackson POTW, Trahon and Big Creek also discharges into Big Creek above the confluence of Big Creek and the Pearl River . Samples of the Pearl River upstream and downstream from the Big Creek confluence contained multiple types of PFAS . The concentrations total PFAS decreased at the downstream site to 30 .78 ppt, resulting in a total PFAS concentration decrease of 1 .89 ppt (5 .79%) . However, three types of PFAS increased slightly at the downstream site, including PFPeA at 13 ppt (8 .33% increase), PFDA at 0 .73 ppt (4 .29% increase), and PFOS at 3 .6 ppt (9 .09% increase) . PFOS (3 .6 ppt) was the only federally regulated PFAS detected downstream at a slightly increased concen- tration . However, PFOA and PFOS both exceeded the draft HHWQC (Water + Organism), indicating the con- centrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFDA, PFHxS, and PFOS also exceeded the EWG health-based criteria . See Ta ble 43 (below). Table 42 | Pearl River Downstream from Jackson POTW, Savanna Street and West Rankin WWTF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Downstream Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 3.60 1000 PFHxA 4.40 1000 PFHpA 1.30 1000 PFOA 2.90 4 0.0009 2.8991 0.09 2.81 PFNA 0.71 0.006 0.704 PFBS 3.00 400 2000 PFHxS 1.30 10 0.001 1.299 PFOS 3.50 4 0.06 3.44 0.3 3.20 Total PFAS 20.71 Non-detect recorded as 0 Exceed criteria levels Table 43 | Pearl River Upstream and Downstream from the Big Creek Confluence Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 4.2 3.8 -0.40 -9.52%1000 PFPeA 12 13 1.00 8.33%1000 PFHxA 3.2 3.2 0.00 0.00%1000 PFHpA 1.2 1.0 -0.20 -16.67%1000 PFOA 3.3 2.8 -0.50 -15.15%4 0.0009 2.7991 0.09 2.71 PFNA 0.67 0.00 -0.67 -100.00%10 0.006 PFDA 0.70 0.73 0.03 4.29%0.006 0.724 PFBS 3.1 1.7 -1.40 -45.16%400 2000 PFHxS 1.0 0.95 -0.05 -5.00%10 0.001 0.949 PFOS 3.3 3.6 0.30 9.09%4 0.06 3.54 0.3 3.30 Total PFAS 32.67 30.78 -1.89 -5.79% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 9594 Tampa Bay Waterkeeper, East Canal, Florida Wastewater Treatment Plant Site The Hillsborough River Watershed covers more than 675 square miles, including the City of Tampa . East Canal is a tributary to Itchepackesassa Creek, which flows into the Hillsborough River and, ultimately, into Hillsborough Bay . Plant City WRF, a municipal wastewater treatment system, owned and operated by the City of Plant City, serves a population of approximately 40,000 residents and discharges into the East Canal .226 EPA has identified 27 potential PFAS-discharging facilities within Plant City .227 Within one mile of the Plant City WRF, 58% of residents are people of color and 50% are low-income . Samples of the East Canal taken downstream from a Plant City WRF outfall detected ten types of PFAS . PFBA (9 ppt), PFPeA (9 .9 ppt), and PFOS (11 ppt) were detected at the highest concentrations . The down- stream site had a total PFAS concentration of 58 .91 ppt . Upstream samples were not collected . Federally regu- lated PFAS were detected at the downstream sampling site, including PFOA, PFNA, PFHxS, PFBS, and PFOS . PFOA (7 .1 ppt) exceeded the MCL by 3 .1 ppt, and PFOS exceeded the MCL by 7 ppt, rendering the sur- face water at this location unsafe for drinking without advanced treatment . PFOA and PFOS exceeded the draft HHWQC (Water + Organism), indicating the con- centrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFNA, PFHxS, and PFOS also exceeded the EWG health-based criteria . See Ta ble 44 (below). Upper Potomac Riverkeeper, Opequon Creek and Back Creek, West Virginia Wastewater Treatment Plant and Biosolids Sites The Opequon Creek Watershed spans approximately 341 square miles across West Virginia and Virginia, with more than half of its area located in West Virginia . Opequon Creek flows into the Potomac River near Martinsburg, West Virginia . The Back Creek Watershed covers 374 square miles in Virginia and West Virginia, before flowing into the Potomac River near Allensville ., West Virginia . Berkeley County operates four sewage treatment and collection systems pursuant to NPDES Permit WV0082759 . One of those systems, Berkeley County PSSD — Inwood WWTP (Outlet 002) serves a pop- ulation of 17,500 residents and discharges to Opequon Creek .228 Of those living within one mile of Inwood WWTP, 13% are people of color and 20% are low income . EPA has identified 2 potential PFAS-discharging facilities within Inwood involving Chemical Manufacturing, Paints and Coatings, and Cleaning Products Manufacturing industries, however, its appears from the NPDES permit that these facilities discharge into a different Berkeley County PSSD facility .229 Samples of Opequon Creek upstream and downstream from an Inwood WWTP outfall contained multiple types of PFAS . While PFPeA, PFHxA, PFOA, and PFBS increased slightly downstream from the WWTP, PFOS slightly decreased, resulting in a total PFAS concentration increase of 1 .8 ppt—an increase of 3 .99% . Only PFPeA and PFBS increased by more than 1 ppt . Regulated PFAS were detected in the downstream samples, including PFOA (4 .1 ppt), PFHxS (3 ppt), PFBS (9 .3 ppt), and PFOS (4 .9 ppt) . PFOA exceeded the MCL by 0 .1 ppt and PFOS exceeded the MCL by 0 .9 ppt, rendering the surface water at this location unsafe for drinking without advanced treatment . PFOA and PFOS also exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFHxS, PFOS, and 8:2 FTS also exceeded the EWG health-based criteria . See Ta ble 45 (below). Table 44 | East Canal Downstream from Plant City WRF Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt)State Surface WQ HH Screening (ppt) Downstream Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 9.00 1000 PFPeA 9.90 1000 PFHxA 6.30 1000 PFHpA 3.70 1000 PFOA 7.10 4 3.10 0.0009 7.0991 0.09 7.01 500 PFNA 1.30 10 0.006 1.294 PFBS 6.00 400 2000 PFPeS 0.71 1 PFHxS 3.90 10 0.001 3.899 PFOS 11.00 4 7.00 0.06 10.94 0.3 10.70 10 1.00 Total PFAS 58.91 Non-detect recorded as 0 Exceed criteria levels Table 45 | Opequon Creek Upstream and Downstream from Berkeley County PSSD — Inwood WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 3.50 3.40 -0.10 -2.86%1000 PFPeA 7.90 9.30 1.40 17.72%1000 PFHxA 6.50 7.20 0.70 10.77%1000 PFHpA 1.60 1.40 -0.20 -12.50%1000 PFOA 3.50 4.10 0.60 17.14%4 0.10 0.0009 4.0991 0.09 4.01 PFBS 8.00 9.30 1.30 16.25%400 2000 PFHxS 3.30 3.00 -0.30 -9.09%10 0.001 2.999 PFOS 5.30 4.90 -0.40 -7.55%4 0.90 0.06 4.84 0.3 4.60 8:2 FTS 5.50 4.30 -1.20 -21.82%1 3.30 Total PFAS 45.10 46.90 1.80 3.99% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 9796 Berkeley County PSSD is permitted to land-apply biosolids produced at its sewage collection and treatment systems .230 Specifically, it is permitted to apply biosolids on fields at 11 agricultural sites at a maximum annual load- ing rate of 1 .5 tons/acre . PFAS sampling was conducted upstream and downstream from the Dehaven Farm, one of Berkeley County PSSD’s land application sites, located in the Back Creek watershed . Samples of Back Creek upstream and downstream from the Dehaven biosolids land application site contained multiple types of PFAS . However, the concentrations of four types of PFAS increased slightly at the downstream site resulting in a total PFAS concentration increase of 0 .61 ppt—an increase of 4 .74% . For example, the concen- tration of PFPeA increased from a non-detect to 1 .4 ppt . Federally regulated PFAS were also detected in down- stream samples, including PFOA (2 ppt), PFBS (1 .7 ppt), PFHxS (1 .8 ppt), and PFOS (2 .1 ppt) . PFOS and PFBS concentrations decreased slightly at the downstream site . PFOA and PFOS exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFHxS, and PFOS also exceeded the EWG health- based criteria . See Ta ble 46 (below). West Virginia Headwaters Waterkeeper, Ohio River, West Virginia Wastewater Treatment Plant Site The Ohio River’s drainage basin covers 204,000 square miles, including most of West Virginia . The river flows 981 miles, providing drinking water to over five million people and handles wastewater from several industrial dischargers . The Parkersburg Utility Board WWTP serves approximately 100,000 residents .231 Within one mile of the Parkersburg WWTP, 8% of residents are peo- ple of color and 56% are low-income . The facility dis- charges treated wastewater to the Ohio River . The EPA has identified 22 potential PFAS-discharging facilities within Parkersburg .232 Samples of the Ohio River upstream and downstream from a Parkersburg WWTP outfall contained multiple types of PFAS . However, only the concentration of PFBS increased slightly in the downstream sample . Federally regulated PFAS were detected downstream, including PFOA (3 .4 ppt), PFNA (0 .67 ppt), PFBS (1 .6 ppt), PFHxS (0 .99 ppt), and PFOS (3 .1 ppt) . PFOA and PFOS exceeded the draft HHWQC (Water + Organism), indicating the concentrations exceeded the levels EPA has identified as being necessary to protect the general population from adverse health effects due to ingesting water, fish, and shellfish from the waterbody . PFOA, PFNA, PFHxS, and PFOS also exceeded the EWG health-based criteria . See Ta ble 47 (below).Table 46 | Back Creek Upstream and Downstream from Biosolids Land Application Fields Analyte Sample (ppt)Duplicate Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 2.3 1.9 -0.40 -17.39%1.9 2.5 0.60 31.58%1000 PFPeA 0.00 1.4 1.40 n/a 0.00 0.00 0.00 0.00%1000 PFHxA 1.8 1.7 -0.10 -5.56%1.5 3.1 1.60 106.67%1000 PFHpA 0.86 0.87 0.01 1.16%0.83 1.0 0.17 20.48%1000 PFOA 1.9 2.0 0.10 5.26%2.3 2.2 -0.10 -4.35%4 0.0009 1.9991 0.09 1.91 PFBS 2.3 1.7 -0.60 -26.09%2.0 2.5 0.50 25.00%400 2000 PFHxS 1.4 1.8 0.40 28.57%2.5 2.2 -0.30 -12.00%10 0.001 1.799 PFOS 2.3 2.1 -0.20 -8.70%3.2 2.7 -0.50 -15.63%4 0.06 2.04 0.3 1.80 Total PFAS 12.86 13.47 0.61 4.74%14.23 16.2 1.97 13.84% Non-detect recorded as 0 Downstream Increase Exceed criteria levels Table 47 | Ohio River Upstream and Downstream from Parkersburg WWTP Analyte Sample (ppt)MCL (ppt)EPA (ppt)EWG (ppt) Upstream Downstream Change % Change Criteria Downstream Exceedance Criteria Downstream Exceedance Criteria Downstream Exceedance PFBA 3.10 3.00 -0.10 -3.23%1000 PFPeA 2.70 2.60 -0.10 -3.70%1000 PFHxA 2.60 2.40 -0.20 -7.69%1000 PFHpA 1.10 1.10 0.00 0.00%1000 PFOA 4.10 3.40 -0.70 -17.07%4 0.0009 3.3991 0.09 3.31 PFNA 0.85 0.67 -0.18 -21.18%10 0.006 0.664 PFDA 0.55 0.00 -0.55 -100.00%0.006 PFBS 1.50 1.60 0.10 6.67%400 2000 PFHxS 1.10 0.99 -0.11 -10.00%10 0.001 0.989 PFOS 3.90 3.10 -0.80 -20.51%4 0.06 3.04 0.3 2.80 HFPO-DA (GenX)0.45 0.00 -0.45 -100.00%10 9 Total PFAS 21.95 18.86 -3.09 -14.08% Non-detect recorded as 0 Downstream Increase Exceed criteria levels WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ANALYSIS AND FINDINGS ANALYSIS AND FINDINGS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 9998 PFAS pose significant societal risks, including health issues, environmental contamination, and economic costs, particu- larly affecting disadvantaged communities . It is essential that PFAS is addressed by the government at both the federal, state, and tribal government levels . The following recommendations propose reforms that policymakers can adopt to prevent or mitigate PFAS pollution . Federal Administrative Policy Reforms Absent comprehensive reform, industry accountability, and substantial investment of federal funds to support affected communities, the short- and long-term harms of PFAS pollution will continue to grow . In May 2025, despite the urgent need for federal action, EPA announced plans to weaken existing national drinking water standards for PFAS . Specifically, the agency proposed rescinding stan- dards for PFHxS, PFNA, and GenX (HFPO-DA), as well as the hazard index that includes those chemicals and PFBS . It also signaled delays in compliance deadlines and new industry loopholes for PFOA and PFOS . Rather than weakening protections, EPA must finalize, adopt, and enforce pending reforms—including the draft HHWQC—to help stem the accumulation of PFAS in the nation’s waterways . Given the well-documented health risks, environmen- tal persistence, and widespread presence of PFAS in surface waters, EPA must regulate these substances as a class rather than individually . This will prevent industries from shifting to unregulated but equally harmful alter- natives . Production and use of PFAS should be phased out entirely . The federal government should also ban the land application of biosolids containing PFAS to stop their spread into the food chain . At a minimum, EPA should lead a coordinated federal response to help state, tribal, and local governments address the public health emergency posed by PFAS . This must include the adoption of effluent limitation guidelines and pretreatment standards for industrial dischargers; enforceable drinking water limits for all PFAS under the SDWA; and national water quality criteria to protect both people and aquatic life under the CWA . Where effluent guidelines are not yet in place, technol- ogy-based discharge limits must be developed using best professional judgment . Funding for wastewater treatment must increase to keep PFAS from being released into sur- face waters that are used for private and public drinking water, recreation, and fish/shellfish consumption . Finally, the federal government must expand monitor- ing of PFAS in surface water, groundwater, and drinking water; strengthen health surveillance; advance scientific research; restore essential monitoring programs; and pro- vide direct assistance to impacted communities—especially in rural areas with high levels of contamination . Congressional Policy Reforms Congress must take action to lessen PFAS’ current impact on the public and adopt policies that will create a last- ing difference . Several measures focused on funding, research, or regulatory oversight have already been intro- duced in Congress that, if passed, would improve public health outcomes related to PFAS . Congress must provide increased funding for wastewa- ter treatment facilities to update their systems to prevent PFAS from returning to the water supply . Congress also needs to provide funding for communities and individuals directly impacted by the failure to protect them from PFAS . As one example, H .R .1517, the Relief for Farmers Hit with PFAS Act, directs the Department of Agriculture to create a grant program to support financial assistance for farmers impacted by PFAS .233 Farmers are especially impacted by the land application of biosolids to their fields . Measures focused on regulatory improvements would lead to a more comprehensive governmental approach to PFAS . This includes reintroduction of the bipartisan, bicameral Clean Water Standards for PFAS Act, which requires EPA to develop water criteria for PFAS under the Clean Water Act, provides the agency with an achievable roadmap to establish ELGs and standards for eight priority industry categories for all measurable PFAS or classes of PFAS within three years, and includes significant federal support to assist communities in upgrading their munici- pal water infrastructure in order to safeguard public health and protect ratepayers .234 S .820, the Protecting Consumers from PFAS Act, which would add the Consumer Product Safety Commission to the list of agencies required to be represented on the PFAS interagency working group, or H .R .5356, the PFAS Act, which would require the Secretary of Transportation to establish a PFAS replacement pro- gram at certain airports . Congress must also fund and implement more strategic and coordinated monitoring of surface waters, ground- water, and drinking water supplies . H .R .5259, the PFAS Exposure Assessment and Documentation Act, shows how the government can invest in testing for PFAS in humans and working with individuals and healthcare systems to educate them and monitor for future risks . More funding is needed for all communities for this kind of health care . State Policy Reforms In 2023, at least 23 states passed 50 bills related to PFAS and, in 2024, at least 17 states passed more than 40 bills related to PFAS .235 Sixteen states have started phasing out or restricting PFAS in various products, including apparel, carpets, cleaning products, cookware, dental floss, fire- fighting foam, food packaging, menstrual products, and personal care items .236 Maine has enacted legislation to phase out the sale of products containing PFAS, and offers financial support to impacted farmers . Minnesota passed a measure prohibiting the use of PFAS in certain consumer products and food packaging . Michigan and New Jersey have established grants to provide financial assistance for addressing PFAS contamination in drinking water systems, and in 2020, New Jersey set drinking water standards for PFOA and PFOS . Additionally, California has banned the use of PFAS in food packaging and products intended for infants and children . In 2020, New Jersey set drinking water standards for PFOA and PFOS . Several states have recently adopted prohibitions, strategies, or standards for biosolids testing and/or land application, including, relevant to this report, Connecticut, Maryland, Michigan, New York, and Wisconsin .237 Numerous states have also adopted regulatory standards to control PFAS in surface waters . See Table 12 (p. 39) . For example, California has established Public Health Goals (PHGs) for certain classes of PFAS that are more stringent than EPA’s MCLs . While PHGs are nonregulatory, the State Water Resources Control Board uses them as a reference when determining the state’s primary drinking water standards and MCLs .238 New Jersey is conducting a study to assess the feasibility of establishing standards, such as MCLs, for the entire class or specific subclasses or mixtures of PFAS in drinking water, rather than for each substance individually .239 States should not wait for the federal government to act on PFAS; they can draw on existing solutions and take swift, decisive action on this critical issue . POLICY RECOMMENDATIONS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II POLICY RECOMENDATIONS WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 101100 1 Carol F . Kwiatkowski et al ., Scientific Basis for Managing PFAS as a Chemical Class, 7 Env’t Sci . & Tech . Letters 532, 533 (2020), doi .org/10 .1021/acs .estlett .0c00255 . 2 Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS), NIEHS, www .niehs .nih .gov/health/topics/agents/pfc (last visited Mar . 27, 2025) (“PFAS are a group of nearly 15,000 synthetic chemicals, according to a chemicals database (CompTox) maintained by the U .S . Environmental Protection Agency .”) . 3 See, e.g., Our Current Understanding of the Human Health and Environmental Risks of PFAS, EPA, www .epa .gov/pfas/our-current-understanding-human- health-and-environmental-risks-pfas (Nov . 26, 2024) . 4 See, e .g ., Kelly L . Smalling et al ., Per- and Polyfluoroalkyl Substances (PFAS) in United States Tapwater: Comparison of Underserved Private-Well and Public- Supply Exposures and Associated Health Implications, 178 Env’t Int’l 108033, 108034 (2023) www .sciencedirect .com/science/article/pii/S0160412023003069 . 5 Draft Sewage Sludge Risk Assessment for Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS), EPA, www .epa .gov/biosolids/draft- sewage-sludge-risk-assessment-perfluorooctanoic-acid-pfoa-and-perfluorooctane (Feb . 21, 2025) . 6 This project is focused on WWTPs that collect and treat wastewater from domestic sewage, commercial businesses, and industries . See Municipal Wastewater, EPA www .epa .gov/npdes/municipal-wastewater (Apr . 19, 2024) . These facilities are commonly referred to as municipal WWTPs (WWTPs), Sewage Treatment Plants (STPs), water resource recovery facilities (WRRF), publicly owned treatment works (POTWs), and similar names . 7 EPA, Information Collection Request 2799 .01, Supporting Statement B, Publicly Owned Treatment Works (POTW) Influent Per- and Polyfluoroalkyl Substances (PFAS) Study and National Sewage Sludge Survey (NSSS) 1-2 (“[t]here are over 50 industrial categories regulated by Effluent Limitations Guidelines and Standards (ELGs) that do not have any PFAS requirements and additional industries that the EPA has determined historically or currently use PFAS but for which insufficient PFAS monitoring data has been identified .”) (2024) www .epa .gov/system/files/documents/2024-10/pfas_potw-icr-supporting-statement-b .pdf . 8 In National Pollutant Discharge Elimination System (NPDES) permits under the Clean Water Act, 33 U .S .C . §§ 1251 et seq ., “[e]ffluent limitations serve as the primary mechanism… for controlling discharges of pollutants to receiving waters . When developing effluent limitations for an NPDES permit, a permit writer must consider limits based on both the technology available to control the pollutants (i .e ., technology-based effluent limits) and limits that are protective of the water quality standards of the receiving water (i .e ., water quality-based effluent limits) .” NPDES Permit Limits, EPA, www .epa .gov/npdes/npdes-permit- limits (Sept . 16, 2024) . 9 Under the Clean Water Act, “[p]retreatment standards are pollutant discharge limits which apply to industrial users [that discharge into municipal WWTPs]… [and] can be expressed as numeric limits, narrative prohibitions, and best management practices (BMPs) .” Pretreatment Standards and Requirements– Applicability, EPA, www .epa .gov/npdes/pretreatment-standards-and-requirements-applicability (Sept . 16, 2024) . 10 EPA, Information Collection Request 2799 .01, Supporting Statement A, POTW Influent Per- and Polyfluoroalkyl Substances (PFAS) Study and National Sewage Sludge Survey (NSSS) 2 (2024) www .epa .gov/system/files/documents/2024-10/pfas_potw-icr-supporting-statement-a .pdf . (“The EPA has not established national technology-based numeric standards for PFAS in wastewater discharges and few states have developed water quality standards for PFAS . Therefore, few industrial facilities have PFAS monitoring requirements, effluent limitations, or pretreatment standards for wastewater discharges .”) 11 EPA, Draft Sewage Sludge Risk Assessment for PFOA and PFOS, Public Webinar 4 (2025), www .epa .gov/system/files/documents/2025-01/draft-ra-public- webinar-slides .pdf . 12 U .S . Environmental Protection Agency (EPA), “Basic Information about Sewage Sludge and Biosolids,” www .epa .gov/biosolids/basic-information-about- sewage-sludge-and-biosolids#statistics (May 13, 2025) 13 See, e.g., EPA, Draft Sewage Sludge Risk Assessment for Perfluorooctanoic Acid (PFOA) CASRN 335-67-1 and Perfluorooctane Sulfonic Acid (PFOS) CASRN 1763-23-1, at 4 (2025), www .epa .gov/system/files/documents/2025-01/draft-sewage-sludge-risk-assessment-pfoa-pfos .pdf . 14 Kelly Hunter Foster & Daniel E . Estrin, Waterkeeper Alliance, Invisible Unbreakable Unnatural: PFAS Contamination of U .S . Surface Waters 7 (2022), waterkeeper .org/wp-content/uploads/2022/10/Waterkeeper-Alliance-PFAS-Report-FINAL-10 .14 .22 .pdf . 15 Id. at 9 . 16 We were able to obtain samples upstream and downstream from 20 WWTPs and 9 sludge land application fields . At two WWTPs and one sludge land application field, we were only able to obtain downstream samples . 17 EPA, Method 1633, Revision A, Analysis of Per- and Polyfluoroalkyl Substances (PFAS) in Aqueous, Solid, Biosolids, and Tissue Samples by LC-MS/MS (2024), www .epa .gov/system/files/documents/2024-12/method-1633a-december-5-2024-508-compliant .pdf (items previously posted in an errata table are addressed in the December 2024 version of EPA Method 1633A) . 18 An equilibrium concentration reflects the point where the amount of PFAS in the sampled medium (here, it is surface water) and the sampler are in balance . See Blessing Medon et . al ., A Field-Validated Equilibrium Passive Sampler for the Monitoring of Per- and Polyfluoroalkyl Substances (PFAS) in Sediment Pore Water and Surface Water, 25 Env’t Sci .: Processes & Impacts 980, 981 (2023) pubs .rsc .org/en/content/articlepdf/2023/em/d2em00483f (“In passive sampling, the amount of analyte accumulated in the sampler increases with time until a dynamic equilibrium is established between the receiving phase and the sampled environment .… [T]he concentration of the analyte in the sampled medium is calculated based on the equilibrium partitioning of the analyte between the receiving phase and the sampled medium .”); see also PFASsive™, Eurofins, www .eurofinsus .com/environment-testing/pfas-testing/services/ passive-sampling/ (last visited Mar . 27, 2025) (“PFASsive™ can be used to provide critical data for fate and risk assessments, toxicity identification and remediation design and/or monitoring that is more representative than conventional grab samples as it quantifies contaminants only in the dissolved form .”) . 19 All publicly available information from multiple sources was gathered from January 1, 2024, through June 18, 2025 . Information may have changed after the time of collection and may not be current at the time of publication . 20 33 U .S .C . §§ 1251 et seq . 21 See, e .g ., Laura Gatz, Regulating PFAS Under the Clean Water Act, Cong . Rsch . Serv ., www .congress .gov/crs_external_products/IF/PDF/IF12148/ IF12148 .5 .pdf (Jan . 15, 2025) . 22 National Recommended Water Quality Criteria - Human Health Criteria Table, EPA, www .epa .gov/wqc/national-recommended-water-quality-criteria-human- health-criteria-table (May 23, 2025) . 23 “Effluent Guidelines are national regulatory standards for wastewater discharged to surface waters and municipal sewage treatment plants . EPA issues these regulations for industrial categories, based on the performance of treatment and control technologies .” Effluent Guidelines, EPA, https://www .epa .gov/eg (Mar . 21, 2025) . 24 “The Clean Water Act prohibits anybody from discharging ‘pollutants’ through a ‘point source’ into a ‘water of the United States’ unless they have an NPDES permit . The permit will contain limits on what you can discharge, monitoring and reporting requirements, and other provisions to ensure that the discharge does not hurt water quality or people’s health,” NPDES Permit Basics, EPA www .epa .gov/npdes/npdes-permit-basics (May 23, 2025) . 25 “The national pretreatment program is designed to: protect POTW infrastructure, and reduce conventional and toxic pollutant levels discharged by industries and other nondomestic wastewater sources into municipal sewer systems and into the environment,” National Pretreatment Program, EPA www .epa .gov/npdes/national-pretreatment-program (May 23, 2025) . 26 PFAS Strategic Roadmap: EPA’s Commitments to Action 2021-2024, EPA, www .epa .gov/pfas/pfas-strategic-roadmap-epas-commitments-action-2021-2024 (May 23, 2025) . 27 Mapping the PFAS Contamination Crisis: New Data Show 9,323 Sites with PFAS in 50 States, the District of Columbia and Four Territories, EWG, www .ewg .org/interactive-maps/pfas_contamination/ (June 12, 2025); see also EPA, Multi-Industry Per- and Polyfluoroalkyl Substances (PFAS) Study – 2021 Preliminary Report 3-9 (2021), www .epa .gov/system/files/documents/2021-09/multi-industry-pfas-study_preliminary-2021-report_508_2021 .09 .08 .pdf (“EPA’s UCMR3 monitoring indicated that public water systems in 33 states serving 16 .5 million residents had detectable levels of long- and short-chain PFAS . Sixty-six public water systems serving more than 6 million people were found to have at least one sample above 70 ng/L, EPA’s lifetime health advisory (LHA) value for the sum of PFOA and PFOS in drinking water… .”) . 28 Per- and Polyfluoroalkyl Substances (PFAS) | State Legislation and Federal Action, Nat’l Conf . of State Legislatures, /www .ncsl .org/environment-and-natural- resources/per-and-polyfluoroalkyl-substances (Jan . 9, 2025) . 29 Per- and Polyfluoroalkyl Substances (PFAS): Final PFAS National Primary Drinking Water Regulation, EPA, www .epa .gov/sdwa/and-polyfluoroalkyl-substances-pfas (Feb . 19, 2025) 30 Designation of PFOA and PFOS as Hazardous Substances Under CERCLA Release Reporting Requirements Factsheet, EPA, www .epa .gov/epcra/designation- pfoa-and-pfos-hazardous-substances-under-cercla-release-reporting-requirements (Aug . 28, 2024) . 31 42 U .S .C . §§ 9601 et seq . 32 Human Health Water Quality Criteria for PFAS, EPA,www .epa .gov/wqc/human-health-water-quality-criteria-pfas (Feb . 21, 2025) . EPA also published final national recommended water quality criteria for the protection of aquatic life for PFOA and informational benchmarks for 8 types of PFAS (PFBA, PFHxA, PFNA, PFDA, PFBS, PFHxS, 8:2 FTUCA, and 7:3 FTCA) on October 7, 2024, see Final Recommended Aquatic Life Criteria and Benchmarks for Select PFAS, 89 Fed . Reg . 810777 (Oct 7, 2024) . 33 EPA Announces It Will Keep Maximum Contaminant Levels for PFOA, PFOS, www .epa .gov/newsreleases/epa-announces-it-will-keep-maximum-contaminant- levels-pfoa-pfos . (May 14, 2025) 34 33 U .S .C . § 1345(d); see also Gatz, supra note 21 (“Section 405(d) also requires EPA to review its biosolids regulations at least every two years to identify additional toxic pollutants that may be present in biosolids and promulgate regulations for those pollutants if sufficient scientific evidence shows they may adversely affect public health or the environment .”) . 35 Hiroko Tabuchi, The EPA Promotes Toxic Fertilizer . 3M told It of Risks Years Ago ., N .Y . Times www .nytimes .com/2024/12/27/climate/epa-pfas-fertilizer-3m- forever-chemicals .html?unlocked_article_code=1 .104 .iE0j .fBMcId1eDgGp&smid=nytcore-ios-share&referringSource=articleShare (Jan . 2, 2025) . 36 Id . 37 One sludge land application site, Virginia’s Old Town Creek, did not have an upstream sample but significant concentrations were detected in the downstream sample . Two WWTP sites did not have upstream samples, Florida’s East Canal and Mississippi’s Pearl River, but significant concentrations were detected in both of the downstream samples . 38 See “Table 3: U .S . EPA Method 1633 Target Analytes” (p. 19), for the unabbreviated scientific name for each type of PFAS discussed in this report . 39 EWG established a health-based guideline of 1 ppt for total PFAS based on the increased risk of cancer, reduced effectiveness of vaccines, and developmental harm . PFAS, Env’t Working Grp ., Tapwater Database (Feb . 2025), www .ewg .org/tapwater/reviewed-pfcs .php . According to EWG, the guideline was “based on studies by Phillipe Grandjean of Harvard University and many other independent researchers who found reduced effectiveness of vaccines and adverse impacts on mammary gland development from exposure to PFOA and PFOS, the two PFAS most widely detected in drinking water . This health guideline applies to the entire class of PFAS detected in water .” CONTAMINANT: Total Per- and Polyfluoroalkyl Substances, Env’t Working Grp ., Tapwater Database www .ewg .org/tapwater/contaminant .php?contamcode=PFAS (last visited Mar . 25, 2025) . 40 See EJSCREEN: Environmental Justice Screening and Mapping Tool, FEMA https://www .fema .gov/emergency-managers/practitioners/recovery-resilience- resource-library/ejscreen-environmental (Mar . 25, 2024) . EPA removed EJScreen from its website on February 5, 2025 . See EDGI_TEAM, EPA Removes EJScreen from Its Website, Env’t Data & Governance Initiative (Feb . 12, 2025), envirodatagov .org/epa-removes-ejscreen-from-its-website; EJScreen, EPA, (last visited Feb . 4, 2025) . However, Waterkeeper Alliance sourced and saved the project data . This data has also been preserved by Public Environmental Data Partners . See EJScreen Environmental Justice Screening and Mapping Tool (Version 2 .3), Public Environmental Data Partners, https://pedp-ejscreen . azurewebsites .net/ (last visited June 17, 2025) . 41 EJScreen includes socioeconomic data, including race and ethnicity, income, unemployment rate, English proficiency, education level, and age . EJScreen also includes data on environmental indicators, including particulate matter 2 .5, ozone, nitrogen dioxide, diesel particulate matter, toxic releases to air, traffic proximity, lead paint, superfund proximity, risk management plan facility proximity, hazardous waste proximity, underground storage tanks, wastewater discharge, and drinking water non-compliance . 42 POTW Influent PFAS Study, EPA, www .epa .gov/eg/potw-influent-pfas-study (Feb . 5, 2025) . 43 Under the Clean Water Act, EPA implements the sewage sludge regulations, 40 CFR Part 503, in 41 states and EPA has authorized nine states (Arizona, Idaho, Michigan, Ohio, Oklahoma, South Dakota, Texas, Utah, and Wisconsin) to administer the Part 503 regulations .” Compliance and Annual Biosolids Reporting, EPA www .epa .gov/biosolids/compliance-and-annual-biosolids-reporting#:~:text=The%20U .S .%20Environmental%20Protection%20Agency,NPDES%20 State%20Program%20Authorization%20Information (June 2, 2025) . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ENDNOTES WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 103102 REFERENCES 44 Devices upstream from the WWTPs located on Florida’s East Canal and Mississippi’s Pearl River were not retrieved . 45 An upstream device was not placed above one sludge land application site located on Virginia’s Old Town Creek . 46 The deployment period extended over 20 or more days for all samplers . The method requires a deployment date of at least 14 days to reach equilibrium . See supra note 18 . 47 See Invisible Unbreakable Unnatural, Waterkeeper All ., waterkeeper .org/pfas/ (last visited Mar . 28, 2025) . 48 See Per- and Polyfluoroalkyl Substances (PFAS), supra note 29; Human Health Water Quality Criteria for PFAS, supra note 32 . 49 See Gatz, supra note 21 . 50 See Tabuchi, supra note 35 . 51 See Mapping the PFAS Contamination Crisis, supra note 27 . 52 See State Legislation and Federal Action, supra note 28 . 53 PFAS Analytic Tools, EPA, awsedap .epa .gov/public/extensions/PFAS_Tools/PFAS_Tools .html (last visited Mar . 18, 2025) . 54 GLWA WRRF has adopted a Local Limit for PFOS of 65 ppt (Daily Maximum) . See Great Lakes Water Auth ., IPP Rules_2024, at 16 (2024), glwa . wpenginepowered .com/wp-content/uploads/2025/01/IPP-Rules_2024 .pdf . 55 See Public Webinar 4, supra note 11, at 6 (discussing findings in reference to PFOA and PFOS) . 56 Id. 57 Id. at 9 . 58 See PFASsive Eurofins, https://www .eurofinsus .com/environment-testing/pfas-testing/services/passive-sampling/ (last visited Mar . 25, 2025) . 59 PFASsive™: Passive Sampler for PFAS, SiREM, www .siremlab .com/PFASsive/ (last visited Mar . 25, 2025) . 60 Id. 61 Id. 62 Includes all downstream sample results where the downstream value exceeded the upstream value, with the exception of the Pearl Riverkeeper and Tampa Bay Waterkeeper sites that do not have upstream samples but whose downstream samples detected significant PFAS concentrations . Also includes a downstream sample from Inland Empire Waterkeeper from August 2024 where there was no upstream sample recovered . Only one type of PFAS, PFBS, was detected at an elevated level downstream from Parkersburg Utility Board . 63 Where a duplicate sample was obtained, the highest value for each analyte is reported . 64 Includes all downstream sample results where the downstream value exceeded the upstream value . No upstream sample was taken on Old Town Creek . Where a duplicate sample was obtained, the highest value for each analyte is reported . 65 See Human Health Water Quality Criteria for PFAS, EPA, supra note 32 66 See Designation of PFOA and PFOS as Hazardous Substances, supra note 30 67 See Per- and Polyfluoroalkyl Substances (PFAS), supra note 29 68 Id. 69 Anna Reade, The Scientific Basis for Managing PFAS as a Chemical Class, Nat . Res . Def . Council (June 30, 2020), www .nrdc .org/bio/anna-reade/scientific- basis-managing-pfas-chemical-class; see generally Kwiatkowski, supra note 1 . 70 See, e.g ., Human and Ecological Health Effects of Select PFAS, Interstate Tech . Regul . Council, § 7 .1 .5 .1, pfas-1 .itrcweb .org/7-human-and-ecological-health- effects-of-select-pfas/ (last visited Mar . 25, 2025); Jesse A . Goodrich et al ., Metabolic Signatures of Youth Exposure to Mixtures of Per- and Polyfluoroalkyl Substances: A Multi-Cohort Study, 131 Env’t Health Perspectives 027005-1, 027005-8 (2023), ehp .niehs .nih .gov/doi/epdf/10 .1289/EHP11372 . 71 Id. at 027005-9 . 72 PFAS, Env’t Working Grp ., Tapwater Database (Feb . 2025), www .ewg .org/tapwater/reviewed-pfcs .php . 73 EWG developed their health-based criteria for PFOA and PFOS based on EPA’s review of toxicity studies and, for numerous other PFAS, based on health assessments published by the EPA and its recommendations for use for similar compounds . See id. 74 42 U .S .C . §§ 300f to 300j–9 (1974). 75 See Per- and Polyfluoroalkyl Substances (PFAS), supra note 29 . 76 See Human Health Water Quality Criteria, supra note 32 . 77 See Per- and Polyfluoroalkyl Substances (PFAS), supra note 29; Surface Water Quality, Interstate Tech . Regul . Council, https://pfas-1 .itrcweb .org/16-surface- water-quality/ (current as of Nov ./Dec . 2024) . 78 In this column, the state, EPA, or EWG is identified as the source of the listed criteria . 79 As noted in this column, PFAS criteria for certain types of PFAS in Oregon, Rhode Island, and Wisconsin are based on the sum of concentrations for multiple PFAS . Additionally, as noted in this column, EPA has established a Hazard Index Value for mixtures containing two or more of PFHxS, PFNA, HFPO-DA, and PFBS . 80 PFDA (Perfluorodecanoic Acid), Env’t Working Grp . Human Toxome Project, www .ewg .org/sites/humantoxome/chemicals/chemical .php?chemid=100301 (last visited Mar . 21, 2025) . 81 Perfluorodecanoic acid (PFDA), Env’t Working Grp ., Tapwater Database, www .ewg .org/tapwater/contaminant .php?contamcode=E285 (Mar . 25, 2025); see also id. 82 See Columbia Env’t Rsch . Ctr ., Study Finds PFOSA Can Suppress Immune Function in Developing Zebrafish (Danio rerio), U .S . Geological Surv . (Aug . 28, 2024), www .usgs .gov/centers/columbia-environmental-research-center/science/study-finds-pfosa-can-suppress-immune . 83 Perfluorooctanesulfonamide (PFOSA), Env’t Working Grp ., Tapwater Database, www .ewg .org/tapwater/contaminant .php?contamcode=E314 (last visited Mar . 21, 2025) . 84 See EPA, ORD Human Health Toxicity Value for 6:2 Fluorotelomer Sulfonic Acid (CASRN 27619-97-2│DTXSID6067331) 3 (2024), cfpub .epa .gov/si/si_public_record_Report .cfm?dirEntryId=363720&Lab=CPHEA . 85 6:2 Fluorotelomer Sulfonate (6:2 FTS), Env’t Working Grp ., Tapwater Database, www .ewg .org/tapwater/contaminant .php?contamcode=E318 (last visited Mar . 21, 2025) . 86 It is notable that there are multiple permitted industrial dischargers to the Sumter Pocotaligo River WWTP that EPA has identified as possibly handling, using, or releasing PFAS chemicals in the metals-related industrial categories, including Armoloy Southeast (Metal Coating), Enersys — Sumter Metals (Metal Machinery Mfg .), Interlake Mecalux (Metal Machinery Mfg .), Metal Finishing Services, Inc . (Metal Coating), and Metokote Corporation (Metal Coating) . 87 Perfluorotetradecanoic Acid, NIH Nat’l Libr . of Med ., Nat’l Ctr . for Biotechnology Info ., pubchem .ncbi .nlm .nih .gov/compound/Perfluorotetradecanoic-acid (last visited Mar . 21, 2025) . 88 Perfluorotetradecanoic Acid (PFTA), Env’t Working Grp ., Tapwater Database, www .ewg .org/tapwater/system-contaminant . php?pws=NC6054001&contamcode=E303 (last visited Mar . 21, 2025) . 89 Perfluoroheptane Sulfonic Acid (PFHpS), Env’t Working Grp ., Tapwater Database, www .ewg .org/tapwater/contaminant .php?contamcode=E312 (last visited Mar . 21, 2025) . 90 Perfluoro-4-methoxybutanic Acid (PFMOBA), Env’t Working Grp ., Tapwater Database, www .ewg .org/tapwater/contaminant .php?contamcode=E331 (last visited Mar . 25, 2025) . 91 N .C . Dep’t Env’t Quality, Fiscal Note for Adoption Amendment of 15A NCAC 02B .0200 and 15A NCAC 02B .0400, at 57–58 (2024), www .deq .nc .gov/ key-issues/july-2b-pfas-ria/open; Minn . Pollution Control Agency, Evaluation of Current Alternatives and Estimated Cost Curves for PFAS Removal and Destruction from Municipal Wastewater, Biosolids, Landfill Leachate, and Compost Contact Water 157–58 (2023), www .pca .state .mn .us/sites/default/files/c- pfc1-26 .pdf . 92 EPA, Multi-Industry Per- and Polyfluoroalkyl Substances (PFAS) Study – 2021 Preliminary Report 1-1 (2021), supra note 27 93 Id. 94 See EPA, Draft Sewage Sludge Risk Assessment, Public Webinar, supra note 11, at 6 . 95 Detailed Facility Report: Sumter Pocataligo River WWTP, EPA ECHO, echo .epa .gov/detailed-facility-report?fid=110017123496 (last visited Jan . 3, 2025) . 96 Id. ECHO statistics last reviewed January 3, 2025 . 97 See PFAS Analytic Tools, supra note 53 . 98 Ambient Surface Water PFAS Monitoring Application, S .C . Dep’t of Env’t Servs ., gis .dhec .sc .gov/gisportal/apps/webappviewer/index . html?id=162b8d1e7fdf459db7ff6b251671651f (last visited Oct . 30, 2024) . 99 For purposes of this report, “regulated” in the section references federal regulations and does not address the range of state regulations of PFAS . 100 City of Graham, Fact Sheet NPDES Permit No . NC0021211 2 (2022), edocs .deq .nc .gov/WaterResources/DocView .aspx?id=2222173&dbid=0&repo=WaterRes ources&searchid=d0cb95d5-63ee-4dce-9a87-de8166e04e21 . 101 Detailed Facility Report: Graham WWTP City of, EPA ECHO, echo .epa .gov/detailed-facility-report?fid=110000761890 (last visited Jan . 3, 2025) . 102 Id. ECHO statistics last reviewed January 3, 2025 . 103 See generally N .C . Dep’t of Env’t Quality, Final NPDES Permit Renewal, Graham WWTP (2022), edocs .deq .nc .gov/WaterResources/DocView .aspx?id=222927 0&dbid=0&repo=WaterResources&searchid=9ad699aa-ee4a-4ae7-8bef-2aa5458fd591 . 104 See PFAS Analytic Tools, supra note 53 . 105 Emerging Compound Facility Sampling, N .C . Dep’t of Env’t Quality, ncdenr .maps .arcgis .com/apps/instant/attachmentviewer/index . html?appid=ed308373c97e4a23a29210fa53a3d404 (last visited Nov . 19, 2024) . 106 See generally City of Graham, City of Graham Land Application 2023 Annual Report (2023) edocs .deq .nc .gov/WaterResources/DocView .aspx?id=3175263&d bid=0&repo=WaterResources&searchid=68b0599d-be54-455f-82c7-0190f3f48ec0 . 107 Id. at § 1, at 1 . 108 Biosolids Facility Report: City Of Graham, EPA ECHO, echo .epa .gov/biosolids-facility-report?id=NCL021211 (last visited Jan . 3, 2025) . 109 See Our Wastewater System, Great Lakes Water Auth ., www .glwater .org/our-system/wastewater-system (last visited Nov . 15, 2024) . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ENDNOTES ENDNOTES WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 105104 110 GLWA WRRFdischarges from three outfalls, only one of which discharges to Rouge River (Outfall 050) . According to the facility’s NPDES permit, GLWA WRRF may not discharge from Outfall 050 “unless hydraulically or structurally necessary .” Mich . Dep’t of Env’t, Great Lakes, and Energy, NPDES Permit No . MI0022802, at 10 (2019), jeffersonchalmerswaterproject .org/323_m_NPDES%20Permit%20-%20FINAL-GLWA%20WRRF .pdf . 111 Great Lakes Water Auth ., Wastewater Master Plan 7-1 (2020), glwa .wpenginepowered .com/wp-content/uploads/2020/12/Full_WWMP_Report_Final_June- 2020 .pdf . 112 Detailed Facility Report: GLWA Water Resource Recovery Facility, EPA ECHO, echo .epa .gov/detailed-facility-report?fid=110000555435&ej_type=sup&ej_ compare=US (last visited Jan . 3, 2025) . 113 Id. ECHO statistics last reviewed January 3, 2025 . 114 Mich . Dep’t of Env’t, Great Lakes, and Energy, NPDES PERMIT NO . MI0022802, at 44 (2019), jeffersonchalmerswaterproject .org/323_m_NPDES%20 Permit%20-%20FINAL-GLWA%20WRRF .pdf . As of 2024, the State of Michigan has set a WQS for PFOS at 11 ppt and a WQBEL for PFOA at 8,040 ppt . See Great Lakes Water Auth ., Status Report — Pollutant Minimization and Source Evaluation Program for PFOS and PFOA 2 (2024), glwa .wpenginepowered .com/ wp-content/uploads/2024/09/PFOA_PFOS-Minimization-Program-May-2024 .pdf . 115 Great Lakes Water Auth ., IPP Rules_2024, supra note 54 at 16 116 See generally Great Lakes Water Auth ., Status Report — Pollutant Minimization and Source Evaluation Program for PFOS and PFOA, supra note 114 117 Id. at attach . 1 . GLWA WRRF defines a “Significant Source” as one where “PFAS-based compounds were identified or used in their processes, or PFOS and/or PFOA concentrations exceed EGLE’s Water Quality Standards (WQS) of 11 [ppt] (PFOS) or 420 [ppt] (PFOA) from one or more sampling events .” Id. at 5 . The facility classifies a facility as a “Potential Source” “where at least one sample result exceeds EGLE’s Water Quality Standards .” Id. at 6 . 118 See PFAS Analytic Tools, supra note 53 . 119 Evaluation of PFAS in Influent, Effluent, and Residuals of Wastewater Treatment Plants (WWTPs) in Michigan, EGLE, Project Number: 60588767 (Apr . 2021), https://www .michigan .gov/egle/-/media/Project/Websites/egle/Documents/Programs/WRD/IPP/pfas-initiatives-statewide-full-report . pdf?rev=90923004ae6448c9a17f0e1f4b3d90de&hash=AB84F5CFA197AC923AC4F51717F75085 . 120 See Status Report — Pollutant Minimization and Source Evaluation Program, supra note 114, at 7 . 121 See id. at attach . 2 . 122 A cement plant with an average facility flow of 0 .0031 MGD in 2024 (St . Marys Cement - Permit No . MI0004243) and a Combined Sewer Overflow outlet with no reported overflow events in 2024 (Wayne Country Rouge River CSO RTB - Permit No . MI0028819) also discharge to this part of the Rouge River . See Pollutant Loading Report (DMR), St . Marys Cement, EPA ECHO, https://echo .epa .gov/trends/loading-tool/reports/dmr-pollutant- loading?permit_id=MI0004243&year=2024 (last visited June 14, 2025); MiEnviro Portal CSO/SSO List, Mich . Env ., Great Lakes, and Energy, https://mienviro . michigan .gov/ncore/external/overflow/list (last visited June 14, 2025) . 123 MCLs, Mich . PFAS Action Response Team, www .michigan .gov/pfasresponse/drinking-water/mcl (last visited April 7, 2025) . 124 Permit Application for 23DP0801, NPDES Permit No . MD0021610, MD Dept . of Env ., https://mes-mde .mde .state .md .us/WastewaterPermitPortal/ (last visited June 17, 2025) . 125 Id. 126 Id. 127 Detailed Facility Report: Frederick WWTP, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110000557166 (last visited June 14, 2025) . ECHO statistics last reviewed June 14, 2025 . 128 Industrial Pretreatment Ordinance (Amended by Ordinance G-15-08), City of Frederick, MD, https://www .cityoffrederickmd .gov/DocumentCenter/ View/4901/G-15-08-Concerning-Industrial-Pretreatment?bidId= (last visited June 14, 2025) . 129 See PFAS Analytic Tools, supra note 53 . 130 Map of Land Application Permits for Biosolids in Maryland, Potomac Riverkeeper Network, https://www .potomacriverkeepernetwork .org/md-biosolids- permit-app-map/ (last visited June 17, 2025); Nutrient Management Plan Update, CA 37: Baungartner & Zack Property, Synagro Permit No . 2017-SAG-5979 (Sept . 17, 2021), https://mdedataviewer .mde .state .md .us/OpenDataDocuments?ID=2216012 . 131 For purposes of analysis, “regulated” in the section references federal regulations and does not address the range of state regulations of PFAS . 132 Or . Dep’t of Env’t Quality, NPDES Permit Renewal Fact Sheet Clean Water Services 10 (2022), ormswd2 .synergydcs .com/HPRMWebDrawer/ RecordView/6369437 . 133 Id. 134 Detailed Facility Report: Rock Creek WRRF, EPA ECHO, echo .epa .gov/detailed-facility-report?fid=110037740068&ej_type=sup&ej_compare=US (last visited Jan . 16, 2025) . 135 Id. ECHO statistics last reviewed January 16, 2025 . 136 Clean Water Servs ., 2022 Annual Report 2, 3 (2022), cleanwaterservices .org/wp-content/uploads/2023/05/2022-NPDES-Annual-Report-Pretreatment- Program .pdf . 137 See generally Or . Dep’t of Env’t Quality, Clean Water Services NPDES Permit (2022), www .oregon .gov/deq/FilterPermitsDocs/MS4CWSPermit .pdf . 138 See PFAS Analytic Tools, supra note 53 . 139 Clean Water Servs ., Introduction to PFAS Efforts at CWS, in Information for March 13, 2024, CWAC Meeting 8 (2024), cleanwaterservices .org/wp-content/ uploads/2024/03/CWAC-Agenda-Packet-03_13_2024 .pdf . 140 Id. at 9 . 141 See NPDES Permit Renewal Fact Sheet Clean Water Services, supra note 132, at 10 . 142 See Introduction to PFAS Efforts at CWS, supra note 139, at 6 . 143 See id. 144 Sewer, City of Riverside, https://riversideca .gov/publicworks/sewer (last visited Nov . 26, 2024) . 145 Detailed Facility Report: Riverside City, Water Quality Control, EPA ECHO, echo .epa .gov/detailed-facility-report?fid=110022399956 (last visited Jan . 3, 2025) . 146 Id. ECHO statistics last reviewed January 3, 2025 . 147 See generally Cal . Reg’l Water Quality Control Bd ., Renewal of Waste Discharge and Producer/User Reclamation Requirements for the Riverside RWQCP (2013), https://www .waterboards .ca .gov/santaana/board_decisions/adopted_orders/orders/2013_orders .html 148 See PFAS Analytic Tools, supra note 53 . 149 Riverside City WWRF (NPD100051476) Influent, CA .gov, geotracker .waterboards .ca .gov/profile_report?cmd=MWEDFResults&global_ id=NPD100051476&assigned_name=CIC (last visited Nov . 27, 2024) . 150 Riverside City WWRF (NPD100051476) Effluent, CA .gov, geotracker .waterboards .ca .gov/profile_report?cmd=MWEDFResults&global_ id=NPD100051476&assigned_name=FCE (last visited Nov . 27, 2024) . 151 Riverside City WWRF (NPD100051476) Biosolids, CA .gov, geotracker .waterboards .ca .gov/profile_report?cmd=MWEDFResults&global_ id=NPD100051476&assigned_name=BIOSOLIDS (last visited Nov . 27, 2024) . 152 The upstream device deployed in August was not recovered . 153 Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS) in Drinking Water, Cal . Off . of Env’t Health Hazard Assessment, oehha .ca .gov/water (last visited April 7, 2025) . 154 Notification Level Issuance, Cal . Water Bds ., www .waterboards .ca .gov/drinking_water/programs/documents/PFHxS-issuance .pdf (last visited April 7, 2025) . 155 City of Waukesha, Permit Fact Sheet 1 (2019), dnr .wisconsin .gov/sites/default/files/topic/WaterUse/Waukesha/WaukeshaWPDESPermitFactsheet .pdf . 156 Wis . Dep’t of Nat . Res ., WPDES Permit 14 (2019), dnr .wisconsin .gov/sites/default/files/topic/WaterUse/Waukesha/WaukeshaWPDESPermit .pdf . 157 City of Waukesha, Description of Process 2 (2023), webfile .waukesha-wi .gov/waukesha/Document_Center/Government/Clean%20Water/Description%20 of%20Water%20Treatment%20Process%20(PDF) .pdf . 158 Detailed Facility Report: Waukesha WWTP, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110000555097 (last visited Jan . 3, 2025) . 159 Id. ECHO statistics last reviewed January 3, 2025 . 160 See generally WPDES Permit, supra note 155 and 156 . 161 See PFAS Analytic Tools, supra note 53 . 162 See WPDES Permit, supra note 156, at 17 . 163 Waukesha City, WPDES Wastewater Discharge Individual Permit Application 34 (2017), https://dnr .wisconsin .gov/sites/default/files/topic/WaterUse/ Waukesha/WaukeshaWPDESpermitApplication .pdf 164 City of Spokane Pub . Works, Application for Renewal of NPDES Municipal Wastewater Discharge Permit 2 (2021), apps .ecology .wa .gov/paris/DownloadDocument .aspx?Id=357285 . Note: This is a Direct Download Link 165 Detailed Facility Report: Spokane City Adv Wastewater Treatment, EPA ECHO, echo .epa .gov/detailed-facility-report?fid=110000562347&ej_type=sup&ej_ compare=US (last visited Jan . 10, 2025) . 166 Id. ECHO statistics last reviewed January 10, 2025 . 167 See generally Wash . Dep’t of Ecology, National Pollutant Discharge Elimination System Waste Discharge Permit No . WA0024473 (2022), https://static .spokanecity .org/documents/publicworks/wastewater/treatmentplant/wa0024473-spokane-rpwrf-permit-2022-09-01 .pdf 168 See PFAS Analytic Tools, supra note 53 . 169 See PFAS Exposure Assessment: Spokane County, Washington, Agency for Toxic Substances and Disease Registry (Nov . 12, 2024), https://www .atsdr .cdc .gov/pfas/exposure-assessments/spokane-county-washington .html 170 Wash . Dep’t of Ecology, Survey of Per- and Poly-fluoroalkyl Substances (PFASs) in Rivers and Lakes, 2016, at 21 (2017), apps .ecology .wa .gov/publications/ documents/1703021 .pdf . 171 Biosolids Facility Report: Spokane Riverside Park AWTF AND CSOS, EPA ECHO, echo .epa .gov/biosolids-facility-report?id=WAL024473 (last visited Jan . 13, 2025) . 172 See Fayetteville Pub . Works Comm’n, Fact Sheet NPDES Permit No . NC0023957 1 (2023), edocs .deq .nc .gov/WaterResources/DocView .aspx?id=2909340&db id=0&repo=WaterResources&searchid=d5043036-153d-404e-bc66-81b60946f3e5&cr=1 . 173 Id. 174 Detailed Facility Report: Fayetteville-Cross Creek WRF, EPA ECHO, echo .epa .gov/detailed-facility-report?fid=110009717002&ej_type=sup&ej_compare=US (last visited Jan . 3, 2025) . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ENDNOTES ENDNOTES WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 107106 209 Emerging Contaminants in N.Y.’s Waters, N .Y . Dep’t of Env’t Conservation, dec .ny .gov/environmental-protection/water/emerging-contaminants (last visited April 7, 2025) . 210 South Central Financial Statements, Year Ended June 30, 2024, scwwa .org/wp-content/uploads/2024/11/South-Central-Wastewater-Authority-2024 .pdf; Detailed Facility Report: South Central Wastewater Authority WWTF, https://echo .epa .gov/detailed-facility-report?fid=110008192918 (last visited June 17, 2025) . 211 See PFAS Analytic Tools, supra note 53 . 212 See generally South Central Wastewater Authority, Request For Proposal, RFP #24-0812 – Biosolids Disposal (2024), govtribe .com/file/government-file/24-0812-scwwa-biosolids-rfp-dot-pdf . 213 Biosolids Facility Report: Petersburg STP, EPA ECHO, echo .epa .gov/biosolids-facility-report?id=VAL025437 (last visited Dec . 9, 2024) . 214 See, e .g, Petersburg Virgina, Sludge Management, http://www .petersburg-va .org/562/Public-Private-Education-Facilities (last visited June 11, 2025); Letter from Carolanne M . Whiteside, Synagro Technical Service Coordinator to Virginia Dept . of Env . Quality, (Mar . 14, 2023), https://www .goochlandva .us/ DocumentCenter/View/9390/Synagro---March-14-2023 (last visited June 11, 2025) . 215 See Permit No . VPA00836, VA Dept . of Env . Quality, https://www .deq .virginia .gov/permits/public-notices/water/land-application-virginia-pollution- abatement-vpa (last visited June 11, 2025) . 216 Detailed Facility Report: Waterbury WPCF, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110035779789 (last accessed June 17, 2025) . 217 See PFAS Analytic Tools, supra note 53 . 218 LA Sanitation City of Los Angeles, Los Angeles-Glendale Water Reclamation Plant, https://sanitation .lacity .gov/san/faces/home/portal/s-lsh-wwd/s-lsh-wwd- cw/s-lsh-wwd-cw-p?_adf .ctrl-state=vdlc0vvep_10&_afrLoop=1540858680529765#! (last visited June 11, 2025); Detailed Facility Report: LA-Glendale WRP, https://echo .epa .gov/detailed-facility-report?fid=110035779789 (last accessed June 17, 2025) . 219 See, LA River Master Plan, Existing Conditions Summary, https://larivermasterplan .org/about/existing-conditions-summary/ and Background, https://larivermasterplan .org/about/background/ (last visited June 11, 2025) . 220 See PFAS Analytic Tools, supra note 53 . 221 See Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS) in Drinking Water, supra note 153 . 222 Detailed Facility Report: Cranston WPCF, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110000735713&ej_type=sup&ej_compare=US (last visited June 17, 2025) . 223 See PFAS Analytic Tools, supra note 53 . 224 Detailed Facility Report: Jackson POTW, Savanna Street, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110000727394&ej_type=sup&ej_ compare=US (last visited June 17, 2025); Detailed Facility Report: West Rankin Utility Authority WWTF, EPA ECHO, https://echo .epa .gov/detailed-facility- report?fid=110064616535 (last visited June 17, 2025); Detailed Facility Report: Jackson POTW, Trahon and Big Creek WWTF, EPA ECHO, https://echo .epa . gov/detailed-facility-report?fid=110055990726 (last visited June 17, 2025) . 225 See PFAS Analytic Tools, supra note 53 . 226 Detailed Facility Report: Plant City WRF, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110035612539 (last visited June 17, 2025) . 227 See PFAS Analytic Tools, supra note 53 . 228 Berkeley Country PSSD - OH/ INW/ BH/ NE 001-004 (Inwood), EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110015983328 (last visited June 17, 2025) . 229 See PFAS Analytic Tools, supra note 53 . 230 Permit No .WV 0082759, West VA Dept . of Env . Protection, at 76, https://documents .dep .wv .gov/AppXtender/datasources/DEPAX16/applications/38/ document/863955?lqid=-1&lqrid=%7B4a55c8f5-63c0-4f64-a610-2d03bfefdc40%7D&lqaid=38&qrid=%7B4a55c8f5-63c0-4f64-a610- 2d03bfefdc40%7D&qridx=0 (last visited June 17, 2025) . 231 Detailed Facility Report: Parkersburg Utility Board, https://echo .epa .gov/detailed-facility-report?fid=110010868016&ej_type=sup&ej_compare=US (last visited June 17, 2025) . 232 See PFAS Analytic Tools, supra note 53 . 233 All bill numbers refer to introductions in the 118th Congress . 234 Pappas, Gillibrand, Fitzpatrick, Kildee Introduce Bipartisan Legislation to Address PFAS Contamination and Hold Polluters Accountable, Congressman Chris Pappas (Apr . 18, 2024), pappas .house .gov/media/press-releases/pappas-gillibrand-fitzpatrick-kildee-introduce-bipartisan-legislation-to-address-pfas- contamination-and-hold-polluters-accountable . 235 See State Legislation and Federal Action, supra note 28 . 236 Our Priorities: PFAS “Forever Chemicals”, Safer States, www .saferstates .org/priorities/pfas/ (last visited Mar . 7, 2025) . 237 See PFAS Land Application Regulations, Most Policy Initiative, https://mostpolicyinitiative .org/science-note/pfas-land-application- regulations/#:~:text=PFAS%20builds%20up%20in%20biosolids%20used%20in%20land%20application .&text=A%20biosolid%20is%20a%20treated,or%20 fertilizer%20(EPA%202025) . (last visited June 15, 2025) . 238 See Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS) in Drinking Water, supra note 153 . 239 Gov. Murphy Signs Nation-Leading PFAs Bill Into Law, More Needed for Strongest Protections, Sierra Club, NJ Chapter (Jan . 22, 2024), www .sierraclub .org/ new-jersey/blog/2024/01/gov-murphy-signs-nation-leading-pfas-bill-law-more-needed-strongest . 175 Id. ECHO statistics last reviewed January 3, 2025 . 176 See generally N .C . Dep’t of Env’t Quality, Final NPDES Permit Renewal, Permit NC0023957 (2023), edocs .deq .nc .gov/WaterResources/DocView .aspx?id=290 9339&dbid=0&repo=WaterResources&searchid=d5043036-153d-404e-bc66-81b60946f3e5 . 177 See PFAS Analytic Tools, supra note 53 . 178 See Emerging Compound Facility Sampling, supra note 105 . 179 For purposes of analysis, “regulated” in the section references federal regulations, and does not address the range of state regulations of PFAS . 180 See generally N .C . Dep’t of Env’t Quality, Land Application of Class B Residuals Permit (2019), edocs .deq .nc .gov/WaterResources/DocView .aspx?id=920822 &dbid=0&repo=WaterResources&searchid=d8fc9053-3116-4ce7-a37f-b09cedc5ea75 . 181 Fayetteville Pub . Works Comm’n, 2023 Residuals Annual Report § 1, at 1 (2023), edocs .deq .nc .gov/WaterResources/DocView .aspx?id=3175577&dbid=0&rep o=WaterResources&searchid=f5b0e17e-63c0-4c4f-a63e-f5f2174afe72 . 182 See generally id. 183 See id. at § 3 . 184 Based on data from 2017 . See Jefferson Cnty . Comm’n, NPDES Form 2A Application Overview, in NPDES Permit Application 2 (2017), lf .adem .alabama .gov/ WebLink/DocView .aspx?id=28528802&dbid=0&cr=1 . 185 See Ala . Dep’t of Env’t Mgmt ., Final Permit Modification 3 (2023),lf .adem .alabama .gov/WebLink/DocView .aspx?id=105201974&dbid=0 . 186 Detailed Facility Report: Cahaba River WWTP, EPA ECHO, echo .epa .gov/detailed-facility-report?fid=110000513249&ej_type=sup&ej_compare=US (last visited Jan . 3, 2025) . 187 Id. ECHO statistics last reviewed January 3, 2025 . 188 See Jefferson Cnty . Comm’n, Pretreatment Program Final, in Jefferson County Environmental Services Department Capacity, Management, Operations and Maintenance (CMOM) Program 2 (2022), www .jccal .org/Sites/Jefferson_County/Documents/Environmental%20Services/2022%20CMOM%20Program%20 Plan%20Combined-09152023 .pdf . 189 See generally Jefferson Cnty . Comm’n, NPDES Permit Application (2017), supra note 184 . 190 See generally Final Permit Modification, supra note 185; see also Ala . Dep’t of Env’t Mgmt ., Draft Permit, Valley Creek WRF (2023), lf .adem .alabama .gov/ WebLink/DocView .aspx?id=105000175&dbid=0&cr=1 . 191 See PFAS Analytic Tools, supra note 53 . 192 For purposes of analysis, “regulated” in the section references federal regulations and does not address the range of state regulations of PFAS . 193 See Jefferson Cnty . Comm’n, 2021 Beneficial Use of By-Product Material, Annual Reporting and Applications 2 (2022), lf .adem .alabama .gov/WebLink/DocView .aspx?id=104822881&dbid=0 . 194 See Ala. Dep’t of Env’t Mgmt., Final Permit Modification, supra note 185; Draft Permit, Valley Creek WRF (2023), supra note 190 . 195 Upon retrieval, the primary downstream sampling device was found to be buried below roughly 4 inches of sediment . The duplicate sample was not buried in sediment at the time of retrieval . This likely accounts for the differences in analytical results between the primary and duplicate downstream samples . 196 Demographic information in this section is sourced from data obtained through EPA EJScreen, see EJScreen supra note 40 . 197 Detailed Facility Report: Homestead WWTP, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110033926278 (last visited June 17, 2025) . 198 See PFAS Analytic Tools, supra note 53 . 199 For purposes of analysis, “regulated” in the section references federal regulations and does not address the range of state regulations of PFAS . 200 Detailed Facility Report: R .M . Clayton WRC, EPA, ECHO, https://echo .epa .gov/detailed-facility-report?fid=110011331022&ej_type=sup&ej_compare=US (last visited June 17, 2025) .; Detailed Facility Report: City of Atlanta CSO West Area, https://echo .epa .gov/detailed-facility-report?fid=110020834533 (last visited June 17, 2025); Detailed Facility Report: R .L . Sutton WRF, https://echo .epa .gov/detailed-facility-report?fid=110009358015 (last visited June 17, 2025) . The sampling sites were also upstream and downstream from two industrial stormwater outfalls associated with an asphalt plant . 201 See PFAS Analytic Tools, supra note 53 . 202 Detailed Facility Report: Rainbow City WWTP, https://echo .epa .gov/detailed-facility-report?fid=110055974147 (last visited June 17, 2025) . 203 Nutrient Managment Plan for the Land Application of Municipal Biosolids From: Utilities Board of Rainbow City, AL, Denali Water Solutions, (Aug . 2023), https://lf .adem .alabama .gov/WebLink/DocView .aspx?id=105181103&dbid=0&cr=1 204 A stormwater outfall (Outfall 003) for Gadsden West River WWTP, NPDES Permit No . AL0053201, is also located in the section of Big Wills Creek between the upstream and downstream sampling sites . 205 Detailed Facility Report: Suffern (V) STP, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110006621496 (last visited June 17, 2025); Detailed Facility Report: Western Ramapo Advanced WWTP, EPA ECHO, https://echo .epa .gov/detailed-facility-report?fid=110020151253 (last visited June 17, 2025) . 206 Disadvantaged Communites Criteria, N .Y . Dep’t of Env’t Conservation, https://climate .ny .gov/Resources/Disadvantaged-Communities-Criteria (last visited June 10, 2025) . 207 See PFAS Analytic Tools, supra note 53 . 208 Ramapo Valley Well Field, Permit No . NY0248258, also discharges untreated groundwater to augment river flow seasonally as needed . Env . Notice Bulletin, Ramapo Valley Well Field Discharge, N .Y . Dep’t of Env’t Conservation, https://dec .ny .gov/news/environmental-notice-bulletin/2023-03-01/completed- application/ramapo-valley-well-field-discharge (last visited June 14, 2025) . WATERKEEPER ALLIANCE | PFAS REPORT PHASE II ENDNOTES ENDNOTES WATERKEEPER ALLIANCE | PFAS REPORT PHASE II 109108 48 From:Biosolids <biosolids-bounces@lists.casaweb.org> on behalf of Maile Lono-Batura via Biosolids <biosolids@lists.casaweb.org> Sent:Tuesday, July 1, 2025 4:09 PM To:Maile Lono-Batura via Biosolids Subject:[CASA Biosolids] Waterkeepers Report Points to WW & Biosolids Attachments:July 2025 Waterkeeper Alliance PFAS Phase II Report_FINAL_6.26.25.pdf; 07-01-2025 Toxic PFAS contamination found in 98% of US waterways.pdf; ATT00001.txt Hello everyone, Please find the aƩached reports and news link below. A recent report from the Waterkeepers Alliance surveyed waterways and PFAS spikes downstream from WWTPs and biosolids applicaƟon fields. While menƟon is made of common household products containing PFAS and careful selecƟon of specific sampling sites to avoid other PFAS sources, the focus of the st udy was on WWTPs and biosolids spikes downstream of their ouƞall or applicaƟon. “Currently, there is liƩle accountability for PFAS entering our environment and water through poorly regulated pathways. American communiƟes are exposed daily, oŌen unknowingly, and many face serious, disproporƟonate health risks. The tools to address this crisis exist, but the poliƟcal will is lacking. We cannot afford more watered-down regulaƟons and loopholes for industrial source polluters. The science is clear: EPA and lawmakers must act decisively, and with urgency, in the public’s interest.” – Mark Yaggi, CEO of Waterkeeper Alliance hƩps://www.chemicalprocessing.com/environmental-protecƟon/water-wastewater/news/55300475/passive-samplers- deployed-in-19-states-detected-pfas-at-nearly-all-tested-sites-with-significant-increases-downstream Please share with others that may be interested. Thank you. Maile Lono-Batura, BCES, MNPL Director of Renewable Resources CA Association of Sanitation Agencies 925 L Street, Suite 200, Sacramento, CA 95814 916.446.0388 (office) | 916.432.3551 (mobile) casaweb.org | @casa_cleanwater | casacleanwater Disclaimer 49 The information contained in this communication from the sender is confidential. It is intended solely for use by the recipient and others authorized to receive it. If you are not the recipient, you are hereby notified that any disclosure, copying, distribution or taking action in relation of the contents of this information is strictly prohibited and may be unlawful. This email has been scanned for viruses and malware, and may have been automatically archived by Mimecast, a leader in email security and cyber resilience. Mimecast integrates email defenses with brand protection, security awareness training, web security, compliance and other essential capabilities. Mimecast helps protect large and small organizations from malicious activity, human error and technology failure; and to lead the movement toward building a more resilient world. To find out more, visit our website. Environment 30th June 2025 ©shutterstock/zimmytws A sweeping new report has uncovered disturbing levels of PFAS contamination in waterways across the United States, raising urgent questions about the safety of the nation’s water supply. Conducted by Waterkeeper Alliance in partnership with local Waterkeeper groups and the Hispanic Access Foundation, the study found that 98% of tested water sites contained per- and poly uoroalkyl substances (PFAS) – a group of toxic, long-lasting industrial chemicals linked to serious health risks. The repor t, par t of a national water monitoring initiative, highlights the per vasive nature of PFAS contamination, par ticularly in areas downstream from wastewater treatment plants (WWTPs) and agricultural elds treated with biosolids. With some sites showing chemical spikes of more than 5,000%, the ndings point to a growing environmental and public health crisis – one that advocates say is being dangerously overlooked at the federal level. A growing PFAS crisis This repor t builds on a 2022 Phase I initiative that found PFAS in 83% of sampled rivers, lakes, and streams across the country. The new ndings, par t of a continued multi-phase investigation, narrowed its focus to speci c high-risk areas – locations downstream of 22 WWTPs and 10 biosolid land application elds in 19 states, many of which serve communities already burdened by environmental inequities. Using PFASsive™ passive sampling technology developed by SiREM, researchers conducted an extended 20-day monitoring effor t that offered more reliable results than traditional spot-check methods. The results were staggering, revealing how deeply entrenched PFAS chemicals are in both urban and rural water systems. Contamination worsens downstream from treatment plants and elds The study showed a signi cant spike in PFAS levels in areas downstream from both WWTPs and biosolids application elds. Contaminant concentrations rose in 95% of sites located below wastewater treatment facilities and 80% of sites downstream from biosolid use. In some cases, the chemical levels surged by thousands of percentage points. One WWTP site recorded a nearly 3,000% increase in total PFAS downstream, reaching 228.29 parts per trillion (ppt ), while a biosolids site reported a 5,100% spike to 106.51 ppt. Among the most commonly detected PFAS were compounds such as PFOA and PFOS – both linked to serious health concerns – as well as unregulated chemicals like PFHxA and PFPeA, which also saw elevated levels downstream. Alarmingly, total PFAS concentrations at every WWTP site and 90% of biosolid sites surpassed the 1 ppt health-based threshold set by the Environmental Working Group, a benchmark widely used in public health assessments. Health and policy implications of the PFAS surge PFAS are known for their resistance to degradation, earning them the nickname ‘forever chemicals.’ Prolonged exposure has been linked to cancer, hormonal disruption, liver damage, and developmental issues. Despite these dangers, federal oversight has lagged behind. Several sampling sites even exceeded proposed national drinking water limits for PFOA and PFOS, compounds the EPA has acknowledged as especially hazardous. Yet, in a concerning turn, the Environmental Protection Agency is currently considering a rollback of proposed rules for several key PFAS chemicals, including PFHxS, PFNA, and GenX. Additionally, the agency has yet to establish any national standards for PFAS in biosolids, despite evidence of their presence in these materials dating back over two decades. According to EPA estimates from 2023, roughly 60% of treated biosolids are applied to land, with about a third spread over agricultural elds, creating a direct pathway for PFAS to enter ecosystems and food chains. Marc Yaggi, CEO of Waterkeeper Alliance, added: “Currently, there is little accountability for PFAS entering our environment and water through poorly regulated pathways. “American communities are exposed daily, often unknowingly, and many face serious, disproportionate health risks. The tools to address this crisis exist, but the political will is lacking. “We cannot afford more watered-down regulations and loopholes for industrial source polluters. The science is clear: EPA and lawmakers must act decisively, and with urgency, in the public’s interest.” A call for stronger protections and immediate action The Waterkeeper Alliance and its par tners are now urging swift and decisive government action to curb PFAS contamination. Their recommendations include setting and enforcing national PFAS limits in drinking water and sur face water discharges under the Safe Drinking Water Act and the Clean Water Act, banning the land application of PFAS-contaminated biosolids, and regulating PFAS as a chemical class to prevent harmful substitutions and streamline remediation effor ts. As PFAS contamination continues to dispropor tionately impact vulnerable communities, the need for federal leadership and funding has never been more urgent. With millions of Americans potentially exposed to these persistent toxins, advocates warn that delaying action risks turning a chemical crisis into a long-term public health disaster. file:///C/...bispo/Documents/PRR26230%20Jorgensen%20-%20WRRF%20Biosolids/Emails/1001-End%20Folder/Attachments/ATT00001.txt[8/25/2026 2:01:46 PM] _______________________________________________ Regulatory mailing list Regulatory@lists.casaweb.org http://lists.casaweb.org/mailman/listinfo/regulatory_lists.casaweb.org 50 From:Washbish, Ryley Sent:Tuesday, June 3, 2025 3:19 PM To:UT_Water_WATERDST Subject:Fw: PFAS Attachments:230123-PFAS Council Memo.pdf; ECOS PFAS Report_Executive Summary.docx See attached information from Chris Lehman regarding PFAS attached. Important to note there has been impact from these chemicals in our drinking water to date, but since you are all out in public daily you might receive questions about it at some point in time. Let me know if you have any questions. Thanks! Ryley Washbish Water Distribution Supervisor Public Utilities Utilities 25 Prado Road, San Luis Obispo, CA 93401-3934 E rwashbish@slocity.org T 805.781.7035 C 805.431.7166 slocity.org Stay connected with the City by signing up for e-notifications From: Lehman, Chris <clehman@slocity.org> Sent: Thursday, May 29, 2025 1:39 PM To: UT_Managers <UT_Managers@slocity.org> Subject: RE: PFAS Following up on the PFAS item from our agenda. Please find the following attached: 1. Utilities Department PFAS memo to City Council. A good introduction to PFAS, the actions the City has taken, and our current exposure. a. A version of this is summarized on the City’s website here: https://www.slocity.org/government/department-directory/utilities-department/water/water- treatment/water-quality b. Please direct any sewer questions from the public to Matt Anderson or myself and water questions to Jason Meeks. 2. Summary of Federal and State developments from the Environmental Council of the States (ECOS), published April 2025. a. I’ve summarized the key takeaways in the attached using ChatGPT. b. The full 250-page report is available here. Thanks, 51 Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications c. -----Original Appointment----- From: Utilities <utilities@slocity.org> Sent: Wednesday, July 6, 2022 8:34 AM To: Utilities; UT_Managers Cc: Schwanemann, Keith; Stuckenberg, Serenity; Claxton, Christina; Lehman, Chris; Anderson, Matt; Meeks, Jason; Whittington, Shane; Beech, Ryan; Floyd, Aaron; Anderson, Kyle; Evans, Noah; McGrath, Patrick; Scott, Shawna; Teague, Nick; Boerman, Mychal; Henderson, Marcus; Parsons, Jake; Buckingham, Meg; Barcenas, Miguel; Aiello, Antonio; Ridgeway, Julie; Washbish, Ryley Subject: Staff Meeting When: Thursday, May 29, 2025 8:00 AM-10:00 AM (UTC-08:00) Pacific Time (US & Canada). Where: 879 Morro, Conference Room Utilities Staff Meeting (Web view) This is the staff meeting that will occur on the third Thursday of every month. ________________________________________________________________________________ Microsoft Teams meeting Join on your computer or mobile app Click here to join the meeting Meeting Download Teams | Join on the web Or call in (audio only) +1 209-645-4165,,543877151# United States, Stockton Phone Conference ID: Find a local number | Reset PIN Learn More | Meeting options 52 ________________________________________________________________________________ City of San Luis Obispo, Council Memorandum DATE: January 23, 2023 TO: Mayor and City Council FROM: Aaron Floyd, Utilities Director VIA: Derek Johnson, City Manager DJJ PREPARED BY: Mychal Boerman, Utilities Deputy Director of Water Nick Teague, Water Resources Program Manager Chris Lehman, Utilities Deputy Director of Wastewater SUBJECT: PFAS IMPACTS TO CITY WATER AND WASTEWATER PURPOSE This memorandum is intended to provide an overview of the current status of a class of chemicals, known largely as PFAS that are gaining local, state, and national attention. Most importantly, to date, there has been NO impact from these chemicals to the City of San Luis Obispo’s drinking water. What follows is a summary of the background, regulatory next steps, and a local status update. Talking points related to this topic are located near the end of this memorandum. PFAS BACKGROUND Per- and poly-fluoroalkyl substances (PFAS) (pronounced P-fas”) have been manufactured and used in a variety of industries in the United States and around the world since the 1940s. In the United States, products containing PFAS continue to be manufactured, although there is a growing regulatory and advocacy movement to restrict or eliminate the use of PFAS. Sources of PFAS include non- stick coatings applied to cookware (Teflon), waterproof clothing such as traditionally manufactured Gore-Tex, and a variety of other commonly used houseful items (Figure 1). Because of the duration and breadth of use across the world, PFAS can be found in surface water, groundwater, soil, and air. Recent studies indicate that exposure to PFAS chemicals at specific levels can adversely impact human health. The Environmental Protection Agency (EPA) has not set actionable regulatory thresholds (maximum contaminant levels or MCLs) for PFAS in drinking water but have released interim Lifetime Health Advisories (LHAs) for some of these constituents1. LHAs are developed by the EPA and identify the maximum concentration of a contaminant in drinking water at which adverse health effects are not anticipated to occur over a lifetime of consumption/use. There are no primary drinking water standards 1 EPA Lifetime Drinking Water Health Advisories for Four Perfluoroalkyl Substances can be found at: https://www.govinfo.gov/content/pkg/FR-2022-06-21/pdf/2022-13158.pdf Figure 1 - Sources of PFAS PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 2 (MCLs) for PFAS in California; however, the Division of Drinking Water has issued Notification Levels (NLs) and Response Levels (RLs) for some PFAS chemicals 2. Notification levels are established as precautionary measures for contaminants that may be considered as potential candidates for establishment of Maximum Contaminant Levels but have not yet undergone or completed the regulatory standard setting process prescribed for the development of Maximum Contaminant Levels and are thus not yet adopted as drinking water standards. They represent the concentration level of a contaminant in drinking water that does not pose a significant health risk but warrants notification. A Response Level (RL) is stricter than a Notification Level and represents a recommended chemical concentration level at which water systems should consider taking a water source out of service or provide treatment to achieve lower concentrations. On October 18, 2021, EPA announced the Agency’s PFAS Strategic Roadmap 3—laying out an approach to address PFAS contamination. The roadmap sets timelines by which EPA plans to take specific actions and new policies to safeguard public health, protect the environment, and hold polluters accountable. The Strategic Roadmap focuses on three central directives: research, restriction, and remediation. Since the release of the Strategic Roadmap the EPA has4: 1. Proposed to designate two PFAS (PFOA and PFOS) as CERCLA (Comprehensive Environmental Response, Compensation and Liability Act 5) hazardous substances 2. Released drinking water health advisories 3. Laid the foundation for enhancing data on PFAS 4. Began distributing $10 billion in funding to address emerging contaminants under the Bipartisan Infrastructure Law (BIL) 5. Expanded the scientific understanding of PFAS 6. Translated the latest science into EPA’s cross-agency PFAS efforts Over the next year, the EPA plans to propose National Drinking Water Standards for PFOA and PFOS, complete CERCLA designations, restrict upstream discharges of PFAS, and address PFAS in wastewater biosolids. PFAS have been added to the list of contaminants to be monitored by public water systems under the Safe Drinking Water Act (SDWA) and the fifth Unregulated Contaminant Monitoring Rule (UCMR 5), published on December 27, 2021 6. UCMR 5 requires that water purveyors sample for 30 chemical contaminants between 2023 and 2025. This action provides EPA and other interested parties with scientifically valid data on the national occurrence of these contaminants in drinking water. Consistent with EPA’s PFAS Strategic Roadmap, UCMR 5 will provide new data that is needed to improve EPA’s 2 PFAS Notification and Response Levels issued by the California Division of Drinking Water can be found at: https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/pfas.html 3 The PFAS Strategic Roadmap: EPA’s Commitments to Action 2021-2024 can be found at: https://www.epa.gov/system/files/documents/2021-10/pfas-roadmap_final-508.pdf 4 EPA’s PFAS Strategic Roadmap: A Year of Progress can be found at: https://www.epa.gov/system/files/documents/2022- 11/PFAS%20Roadmap%20Progress%20Report_final_Nov%2017.pdf 5 42 USC Ch. 103: Comprehensive Environmental Response, Compensation, and Liability can be found at: https://uscode.house.gov/view.xhtml?path=/prelim@title42/chapter103&edition=prelim 6 The Fifth Unregulated Contaminant Monitoring Rule (UCMR 5); Program Overview Fact Sheet can be found at: https://www.epa.gov/system/files/documents/2022-02/ucmr5-factsheet.pdf PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 3 understanding of the frequency of 29 PFAS contaminants in the nation’s drinking water systems and at what concentrations they are found. LOCAL WATER SUPPLY IMPACTS FROM PFAS Currently, the City’s drinking water is not impacted by PFAS, largely because the City receives its drinking water from rural surface water sources, away from sources of contamination. PFAS contamination enters the environment at sites where PFAS are made, used, disposed of, or spilled. Studies have shown that PFAS contamination of groundwater increases with increasing urbanization. Once in groundwater, PFAS are easily transported large distances, tend to accumulate in groundwater, and can contaminate drinking water wells. Non-City wells within the Airport Area and adjacent areas around Buckley Road and Suburban Road have had positive detections of PFAS7. Groundwater sampling done as part of the City’s Prop 1 funded groundwater study showed levels of PFAS greater than the California Response Level in non-water-supply wells within City limits, adjacent to Highway 101 between Los Osos Valley Road and Madonna Road. The City’s only active water supply well, Pacific Beach Well, which has not been used since 2015, was tested and did not contain PFAS. As the City develops its groundwater program the Utilities Department will ensure that a groundwater sampling and monitoring program is developed to maximize the understanding of the local PFAS contamination, and that appropriate treatment technologies are implemented to ensure that PFAS contaminated drinking water is not delivered to the community. PFAS DETECTION IN WASTEWATER In 2020 and 2021, the City’s Water Resource Recovery Facility (WRRF) was required to complete four quarters of sampling for PFAS. Per the Statewide Investigative Order (WQ-2020-0015-DWQ), the WRRF’s influent, effluent, and biosolids were sampled and reported to the State Water Board’s Geotracker database. This statewide data collection study was completed for all wastewater treatment plants in California rated to treat flows above one million gallons per day. Results of the sampling indicated that the City had only trace concentrations of PFAS in biosolids material. Because PFAS are pervasive in consumer products, they can make their way into the wastewater stream via showering, dishwashing, clothes washing, and other activities, and are not always 7 The State Water Resources Control Board GeoTracker PFAS Map application can be found at: https://geotracker.waterboards.ca.gov/map/pfas_map Figure 2 - How PFAS collects in Sewage PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 4 attributable to drinking water contamination. In the City’s case, where PFAS is not present is drinking water, presence in biosolids is likely attributable to personal use of products containing PFAS. As drinking water standards for PFAS emerge, it is likely that PFAS standards for wastewater effluent and wastewater biosolids will also be developed. NEXT STEPS Utilities Department staff will remain proactive in communicating regarding local groundwater contamination and the work being done to ensure that drinking water provided to our community will not adversely impact public health. The talking points listed below reflect the current understanding of PFAS and will be updated as more information is available. TALKING POINTS: 1. The City’s drinking water is not currently impacted by PFAS, largely because the City receives its drinking water from rural surface water sources instead of groundwater wells underlying urban areas where PFAS generally accumulates. 2. The City will continue to monitor water, wastewater, and biosolids for PFAS, as required by EPA and State of California regulations. Figure 3 - Median California Biosolids Concentrations in Context PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 5 3. When the City’s groundwater program is expanded, sampling, monitoring, and treatment of any PFAS contamination will be conducted prior to delivery of groundwater to the community. 4. While the EPA and State of California have not set actionable regulatory thresholds for PFAS in drinking water, they are in the process of developing them. The department will communicate with the public as these standards are finalized. 5. PFAS has been detected in groundwater within City limits and is prevalent in groundwater regionally, statewide, and nationally and is not a source of drinking water. 6. The City is not currently delivering groundwater and all of the City’s surface water supplies are free of PFAS contamination. 7. When groundwater wells are used, they will include treatment systems to remove groundwater contamination, including PFAS. 8. PFAS vs PCE vs TCE a. PFAS are a group of manufactured substances that are found in many different consumer, commercial, and industrial products (Teflon, GORE-TEX, cosmetics, non-stick cookware, firefighting foam 8, etc.). This makes it challenging to study and assess the potential human health and environmental risks. PFAS has been detected in groundwater from the airport west to Highway 101. B. PCE is a chemical widely used in dry-cleaning fabrics and metal degreasing operations. This is the chemical that has been detected in groundwater in the San Luis Valley groundwater subarea adjacent to San Luis Obispo Creek between downtown and Los Osos Valley Road and was the subject of the City’s recent groundwater project9. PCE will be removed before any use of local groundwater for municipal drinking water purposes. C. TCE is a chemical used mostly in industrial and commercial processes such as cleaning and furniture care products, arts and crafts spray coatings, and automotive care products like brake cleaners. TCE has been detected in groundwater in the area around Buckley Road10; however, it is not present in groundwater underlying the City, nor is it present in our municipal drinking water supplies. If you have questions, please feel free to reach out to Aaron Floyd, Utilities Director 8 The San Luis Obispo Fire Department no longer uses firefighting foam that contains PFAS. Foams in use by the San Luis Obispo Fire Department include PHOS-CHEK® WD881 (https://www.perimeter-solutions.com/wp- content/uploads/2021/08/PHOS-CHEK-WD881-EN-OSHA-WHMIS-GHS-SDS-2020-06-18.pdf) and SOLBERG® RE- HEALING™ RF3 (https://www.perimeter-solutions.com/wp- content/uploads/2021/06/PERI_Rehealing_RF3_3_FoamConcentrate_Datasheet_v1.pdf) 9 Information on the City of San Luis Obispo Groundwater Enhancement Project can be found at: https://www.slocity.org/government/department-directory/utilities-department/water/water- sources/groundwater 10 Information on the Central Coast Regional Water Quality Control Board investigation of trichloroethylene (TCE) in groundwater in the Buckley Road area can be found at: https://www.waterboards.ca.gov/centralcoast/water_issues/hot_topics/tce_pce_info/tce_pce_index.html 53 From:Scott, Shawna Sent:Thursday, May 29, 2025 4:31 PM To:Gurney, Nico Subject:FW: PFAS Attachments:230123-PFAS Council Memo.pdf; ECOS PFAS Report_Executive Summary.docx From: Lehman, Chris <clehman@slocity.org> Sent: Thursday, May 29, 2025 1:40 PM To: UT_Managers <UT_Managers@slocity.org> Subject: RE: PFAS Following up on the PFAS item from our agenda. Please find the following attached: 1) Utilities Department PFAS memo to City Council. A good introduction to PFAS, the actions the City has taken, and our current exposure. a. A version of this is summarized on the City’s website here: https://www.slocity.org/government/department-directory/utilities-department/water/water- treatment/water-quality b. Please direct any sewer questions from the public to Matt Anderson or myself and water questions to Jason Meeks. 2) Summary of Federal and State developments from the Environmental Council of the States (ECOS), published April 2025. a. I’ve summarized the key takeaways in the attached using ChatGPT. b. The full 250-page report is available here. Thanks, Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications c. -----Original Appointment----- From: Utilities <utilities@slocity.org> Sent: Wednesday, July 6, 2022 8:34 AM To: Utilities; UT_Managers Cc: Schwanemann, Keith; Stuckenberg, Serenity; Claxton, Christina; Lehman, Chris; Anderson, Matt; Meeks, Jason; Whittington, Shane; Beech, Ryan; Floyd, Aaron; Anderson, Kyle; Evans, Noah; McGrath, Patrick; Scott, Shawna; Teague, Nick; Boerman, 54 Mychal; Henderson, Marcus; Parsons, Jake; Buckingham, Meg; Barcenas, Miguel; Aiello, Antonio; Ridgeway, Julie; Washbish, Ryley Subject: Staff Meeting When: Thursday, May 29, 2025 8:00 AM-10:00 AM (UTC-08:00) Pacific Time (US & Canada). Where: 879 Morro, Conference Room Utilities Staff Meeting (Web view) This is the staff meeting that will occur on the third Thursday of every month. ________________________________________________________________________________ Microsoft Teams meeting Join on your computer or mobile app Click here to join the meeting Meeting ID: Download Teams | Join on the web Or call in (audio only) +1 209-645-4165,,543877151# United States, Stockton Phone Conference ID: Find a local number | Reset PIN Learn More | Meeting options ________________________________________________________________________________ City of San Luis Obispo, Council Memorandum DATE: January 23, 2023 TO: Mayor and City Council FROM: Aaron Floyd, Utilities Director VIA: Derek Johnson, City Manager DJJ PREPARED BY: Mychal Boerman, Utilities Deputy Director of Water Nick Teague, Water Resources Program Manager Chris Lehman, Utilities Deputy Director of Wastewater SUBJECT: PFAS IMPACTS TO CITY WATER AND WASTEWATER PURPOSE This memorandum is intended to provide an overview of the current status of a class of chemicals, known largely as PFAS that are gaining local, state, and national attention. Most importantly, to date, there has been NO impact from these chemicals to the City of San Luis Obispo’s drinking water. What follows is a summary of the background, regulatory next steps, and a local status update. Talking points related to this topic are located near the end of this memorandum. PFAS BACKGROUND Per- and poly-fluoroalkyl substances (PFAS) (pronounced P-fas”) have been manufactured and used in a variety of industries in the United States and around the world since the 1940s. In the United States, products containing PFAS continue to be manufactured, although there is a growing regulatory and advocacy movement to restrict or eliminate the use of PFAS. Sources of PFAS include non- stick coatings applied to cookware (Teflon), waterproof clothing such as traditionally manufactured Gore-Tex, and a variety of other commonly used houseful items (Figure 1). Because of the duration and breadth of use across the world, PFAS can be found in surface water, groundwater, soil, and air. Recent studies indicate that exposure to PFAS chemicals at specific levels can adversely impact human health. The Environmental Protection Agency (EPA) has not set actionable regulatory thresholds (maximum contaminant levels or MCLs) for PFAS in drinking water but have released interim Lifetime Health Advisories (LHAs) for some of these constituents1. LHAs are developed by the EPA and identify the maximum concentration of a contaminant in drinking water at which adverse health effects are not anticipated to occur over a lifetime of consumption/use. There are no primary drinking water standards 1 EPA Lifetime Drinking Water Health Advisories for Four Perfluoroalkyl Substances can be found at: https://www.govinfo.gov/content/pkg/FR-2022-06-21/pdf/2022-13158.pdf Figure 1 - Sources of PFAS PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 2 (MCLs) for PFAS in California; however, the Division of Drinking Water has issued Notification Levels (NLs) and Response Levels (RLs) for some PFAS chemicals 2. Notification levels are established as precautionary measures for contaminants that may be considered as potential candidates for establishment of Maximum Contaminant Levels but have not yet undergone or completed the regulatory standard setting process prescribed for the development of Maximum Contaminant Levels and are thus not yet adopted as drinking water standards. They represent the concentration level of a contaminant in drinking water that does not pose a significant health risk but warrants notification. A Response Level (RL) is stricter than a Notification Level and represents a recommended chemical concentration level at which water systems should consider taking a water source out of service or provide treatment to achieve lower concentrations. On October 18, 2021, EPA announced the Agency’s PFAS Strategic Roadmap 3—laying out an approach to address PFAS contamination. The roadmap sets timelines by which EPA plans to take specific actions and new policies to safeguard public health, protect the environment, and hold polluters accountable. The Strategic Roadmap focuses on three central directives: research, restriction, and remediation. Since the release of the Strategic Roadmap the EPA has4: 1. Proposed to designate two PFAS (PFOA and PFOS) as CERCLA (Comprehensive Environmental Response, Compensation and Liability Act 5) hazardous substances 2. Released drinking water health advisories 3. Laid the foundation for enhancing data on PFAS 4. Began distributing $10 billion in funding to address emerging contaminants under the Bipartisan Infrastructure Law (BIL) 5. Expanded the scientific understanding of PFAS 6. Translated the latest science into EPA’s cross-agency PFAS efforts Over the next year, the EPA plans to propose National Drinking Water Standards for PFOA and PFOS, complete CERCLA designations, restrict upstream discharges of PFAS, and address PFAS in wastewater biosolids. PFAS have been added to the list of contaminants to be monitored by public water systems under the Safe Drinking Water Act (SDWA) and the fifth Unregulated Contaminant Monitoring Rule (UCMR 5), published on December 27, 2021 6. UCMR 5 requires that water purveyors sample for 30 chemical contaminants between 2023 and 2025. This action provides EPA and other interested parties with scientifically valid data on the national occurrence of these contaminants in drinking water. Consistent with EPA’s PFAS Strategic Roadmap, UCMR 5 will provide new data that is needed to improve EPA’s 2 PFAS Notification and Response Levels issued by the California Division of Drinking Water can be found at: https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/pfas.html 3 The PFAS Strategic Roadmap: EPA’s Commitments to Action 2021-2024 can be found at: https://www.epa.gov/system/files/documents/2021-10/pfas-roadmap_final-508.pdf 4 EPA’s PFAS Strategic Roadmap: A Year of Progress can be found at: https://www.epa.gov/system/files/documents/2022- 11/PFAS%20Roadmap%20Progress%20Report_final_Nov%2017.pdf 5 42 USC Ch. 103: Comprehensive Environmental Response, Compensation, and Liability can be found at: https://uscode.house.gov/view.xhtml?path=/prelim@title42/chapter103&edition=prelim 6 The Fifth Unregulated Contaminant Monitoring Rule (UCMR 5); Program Overview Fact Sheet can be found at: https://www.epa.gov/system/files/documents/2022-02/ucmr5-factsheet.pdf PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 3 understanding of the frequency of 29 PFAS contaminants in the nation’s drinking water systems and at what concentrations they are found. LOCAL WATER SUPPLY IMPACTS FROM PFAS Currently, the City’s drinking water is not impacted by PFAS, largely because the City receives its drinking water from rural surface water sources, away from sources of contamination. PFAS contamination enters the environment at sites where PFAS are made, used, disposed of, or spilled. Studies have shown that PFAS contamination of groundwater increases with increasing urbanization. Once in groundwater, PFAS are easily transported large distances, tend to accumulate in groundwater, and can contaminate drinking water wells. Non-City wells within the Airport Area and adjacent areas around Buckley Road and Suburban Road have had positive detections of PFAS7. Groundwater sampling done as part of the City’s Prop 1 funded groundwater study showed levels of PFAS greater than the California Response Level in non-water-supply wells within City limits, adjacent to Highway 101 between Los Osos Valley Road and Madonna Road. The City’s only active water supply well, Pacific Beach Well, which has not been used since 2015, was tested and did not contain PFAS. As the City develops its groundwater program the Utilities Department will ensure that a groundwater sampling and monitoring program is developed to maximize the understanding of the local PFAS contamination, and that appropriate treatment technologies are implemented to ensure that PFAS contaminated drinking water is not delivered to the community. PFAS DETECTION IN WASTEWATER In 2020 and 2021, the City’s Water Resource Recovery Facility (WRRF) was required to complete four quarters of sampling for PFAS. Per the Statewide Investigative Order (WQ-2020-0015-DWQ), the WRRF’s influent, effluent, and biosolids were sampled and reported to the State Water Board’s Geotracker database. This statewide data collection study was completed for all wastewater treatment plants in California rated to treat flows above one million gallons per day. Results of the sampling indicated that the City had only trace concentrations of PFAS in biosolids material. Because PFAS are pervasive in consumer products, they can make their way into the wastewater stream via showering, dishwashing, clothes washing, and other activities, and are not always 7 The State Water Resources Control Board GeoTracker PFAS Map application can be found at: https://geotracker.waterboards.ca.gov/map/pfas_map Figure 2 - How PFAS collects in Sewage PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 4 attributable to drinking water contamination. In the City’s case, where PFAS is not present is drinking water, presence in biosolids is likely attributable to personal use of products containing PFAS. As drinking water standards for PFAS emerge, it is likely that PFAS standards for wastewater effluent and wastewater biosolids will also be developed. NEXT STEPS Utilities Department staff will remain proactive in communicating regarding local groundwater contamination and the work being done to ensure that drinking water provided to our community will not adversely impact public health. The talking points listed below reflect the current understanding of PFAS and will be updated as more information is available. TALKING POINTS: 1. The City’s drinking water is not currently impacted by PFAS, largely because the City receives its drinking water from rural surface water sources instead of groundwater wells underlying urban areas where PFAS generally accumulates. 2. The City will continue to monitor water, wastewater, and biosolids for PFAS, as required by EPA and State of California regulations. Figure 3 - Median California Biosolids Concentrations in Context PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 5 3. When the City’s groundwater program is expanded, sampling, monitoring, and treatment of any PFAS contamination will be conducted prior to delivery of groundwater to the community. 4. While the EPA and State of California have not set actionable regulatory thresholds for PFAS in drinking water, they are in the process of developing them. The department will communicate with the public as these standards are finalized. 5. PFAS has been detected in groundwater within City limits and is prevalent in groundwater regionally, statewide, and nationally and is not a source of drinking water. 6. The City is not currently delivering groundwater and all of the City’s surface water supplies are free of PFAS contamination. 7. When groundwater wells are used, they will include treatment systems to remove groundwater contamination, including PFAS. 8. PFAS vs PCE vs TCE a. PFAS are a group of manufactured substances that are found in many different consumer, commercial, and industrial products (Teflon, GORE-TEX, cosmetics, non-stick cookware, firefighting foam 8, etc.). This makes it challenging to study and assess the potential human health and environmental risks. PFAS has been detected in groundwater from the airport west to Highway 101. B. PCE is a chemical widely used in dry-cleaning fabrics and metal degreasing operations. This is the chemical that has been detected in groundwater in the San Luis Valley groundwater subarea adjacent to San Luis Obispo Creek between downtown and Los Osos Valley Road and was the subject of the City’s recent groundwater project9. PCE will be removed before any use of local groundwater for municipal drinking water purposes. C. TCE is a chemical used mostly in industrial and commercial processes such as cleaning and furniture care products, arts and crafts spray coatings, and automotive care products like brake cleaners. TCE has been detected in groundwater in the area around Buckley Road10; however, it is not present in groundwater underlying the City, nor is it present in our municipal drinking water supplies. If you have questions, please feel free to reach out to Aaron Floyd, Utilities Director 8 The San Luis Obispo Fire Department no longer uses firefighting foam that contains PFAS. Foams in use by the San Luis Obispo Fire Department include PHOS-CHEK® WD881 (https://www.perimeter-solutions.com/wp- content/uploads/2021/08/PHOS-CHEK-WD881-EN-OSHA-WHMIS-GHS-SDS-2020-06-18.pdf) and SOLBERG® RE- HEALING™ RF3 (https://www.perimeter-solutions.com/wp- content/uploads/2021/06/PERI_Rehealing_RF3_3_FoamConcentrate_Datasheet_v1.pdf) 9 Information on the City of San Luis Obispo Groundwater Enhancement Project can be found at: https://www.slocity.org/government/department-directory/utilities-department/water/water- sources/groundwater 10 Information on the Central Coast Regional Water Quality Control Board investigation of trichloroethylene (TCE) in groundwater in the Buckley Road area can be found at: https://www.waterboards.ca.gov/centralcoast/water_issues/hot_topics/tce_pce_info/tce_pce_index.html 55 From:Anderson, Matt Sent:Thursday, May 29, 2025 1:47 PM To:Chen, Bryan; Parsons, Patrice; Rose, Jill; Rauh, Emory; Seng, Geraldine; Melby, Jordan Subject:FW: PFAS Attachments:230123-PFAS Council Memo.pdf; ECOS PFAS Report_Executive Summary.docx FYI – PFAS has been in the news with recent changes at the federal level. The city prepared a response and communication document, linked below. From: Lehman, Chris <clehman@slocity.org> Sent: Thursday, May 29, 2025 1:40 PM To: UT_Managers <UT_Managers@slocity.org> Subject: RE: PFAS Following up on the PFAS item from our agenda. Please find the following attached: 1) Utilities Department PFAS memo to City Council. A good introduction to PFAS, the actions the City has taken, and our current exposure. a. A version of this is summarized on the City’s website here: https://www.slocity.org/government/department-directory/utilities-department/water/water- treatment/water-quality b. Please direct any sewer questions from the public to Matt Anderson or myself and water questions to Jason Meeks. 2) Summary of Federal and State developments from the Environmental Council of the States (ECOS), published April 2025. a. I’ve summarized the key takeaways in the attached using ChatGPT. b. The full 250-page report is available here. Thanks, Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications c. -----Original Appointment----- From: Utilities <utilities@slocity.org> Sent: Wednesday, July 6, 2022 8:34 AM To: Utilities; UT_Managers Cc: Schwanemann, Keith; Stuckenberg, Serenity; Claxton, Christina; Lehman, Chris; Anderson, Matt; Meeks, Jason; Whittington, 56 Shane; Beech, Ryan; Floyd, Aaron; Anderson, Kyle; Evans, Noah; McGrath, Patrick; Scott, Shawna; Teague, Nick; Boerman, Mychal; Henderson, Marcus; Parsons, Jake; Buckingham, Meg; Barcenas, Miguel; Aiello, Antonio; Ridgeway, Julie; Washbish, Ryley Subject: Staff Meeting When: Thursday, May 29, 2025 8:00 AM-10:00 AM (UTC-08:00) Pacific Time (US & Canada). Where: 879 Morro, Conference Room Utilities Staff Meeting (Web view) This is the staff meeting that will occur on the third Thursday of every month. ________________________________________________________________________________ Microsoft Teams meeting Join on your computer or mobile app Click here to join the meeting Meeting Download Teams | Join on the web Or call in (audio only) +1 209-645-4165,,543877151# United States, Stockton Phone Conference ID: Find a local number | Reset PIN Learn More | Meeting options ________________________________________________________________________________ City of San Luis Obispo, Council Memorandum DATE: January 23, 2023 TO: Mayor and City Council FROM: Aaron Floyd, Utilities Director VIA: Derek Johnson, City Manager DJJ PREPARED BY: Mychal Boerman, Utilities Deputy Director of Water Nick Teague, Water Resources Program Manager Chris Lehman, Utilities Deputy Director of Wastewater SUBJECT: PFAS IMPACTS TO CITY WATER AND WASTEWATER PURPOSE This memorandum is intended to provide an overview of the current status of a class of chemicals, known largely as PFAS that are gaining local, state, and national attention. Most importantly, to date, there has been NO impact from these chemicals to the City of San Luis Obispo’s drinking water. What follows is a summary of the background, regulatory next steps, and a local status update. Talking points related to this topic are located near the end of this memorandum. PFAS BACKGROUND Per- and poly-fluoroalkyl substances (PFAS) (pronounced P-fas”) have been manufactured and used in a variety of industries in the United States and around the world since the 1940s. In the United States, products containing PFAS continue to be manufactured, although there is a growing regulatory and advocacy movement to restrict or eliminate the use of PFAS. Sources of PFAS include non- stick coatings applied to cookware (Teflon), waterproof clothing such as traditionally manufactured Gore-Tex, and a variety of other commonly used houseful items (Figure 1). Because of the duration and breadth of use across the world, PFAS can be found in surface water, groundwater, soil, and air. Recent studies indicate that exposure to PFAS chemicals at specific levels can adversely impact human health. The Environmental Protection Agency (EPA) has not set actionable regulatory thresholds (maximum contaminant levels or MCLs) for PFAS in drinking water but have released interim Lifetime Health Advisories (LHAs) for some of these constituents1. LHAs are developed by the EPA and identify the maximum concentration of a contaminant in drinking water at which adverse health effects are not anticipated to occur over a lifetime of consumption/use. There are no primary drinking water standards 1 EPA Lifetime Drinking Water Health Advisories for Four Perfluoroalkyl Substances can be found at: https://www.govinfo.gov/content/pkg/FR-2022-06-21/pdf/2022-13158.pdf Figure 1 - Sources of PFAS PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 2 (MCLs) for PFAS in California; however, the Division of Drinking Water has issued Notification Levels (NLs) and Response Levels (RLs) for some PFAS chemicals 2. Notification levels are established as precautionary measures for contaminants that may be considered as potential candidates for establishment of Maximum Contaminant Levels but have not yet undergone or completed the regulatory standard setting process prescribed for the development of Maximum Contaminant Levels and are thus not yet adopted as drinking water standards. They represent the concentration level of a contaminant in drinking water that does not pose a significant health risk but warrants notification. A Response Level (RL) is stricter than a Notification Level and represents a recommended chemical concentration level at which water systems should consider taking a water source out of service or provide treatment to achieve lower concentrations. On October 18, 2021, EPA announced the Agency’s PFAS Strategic Roadmap 3—laying out an approach to address PFAS contamination. The roadmap sets timelines by which EPA plans to take specific actions and new policies to safeguard public health, protect the environment, and hold polluters accountable. The Strategic Roadmap focuses on three central directives: research, restriction, and remediation. Since the release of the Strategic Roadmap the EPA has4: 1. Proposed to designate two PFAS (PFOA and PFOS) as CERCLA (Comprehensive Environmental Response, Compensation and Liability Act 5) hazardous substances 2. Released drinking water health advisories 3. Laid the foundation for enhancing data on PFAS 4. Began distributing $10 billion in funding to address emerging contaminants under the Bipartisan Infrastructure Law (BIL) 5. Expanded the scientific understanding of PFAS 6. Translated the latest science into EPA’s cross-agency PFAS efforts Over the next year, the EPA plans to propose National Drinking Water Standards for PFOA and PFOS, complete CERCLA designations, restrict upstream discharges of PFAS, and address PFAS in wastewater biosolids. PFAS have been added to the list of contaminants to be monitored by public water systems under the Safe Drinking Water Act (SDWA) and the fifth Unregulated Contaminant Monitoring Rule (UCMR 5), published on December 27, 2021 6. UCMR 5 requires that water purveyors sample for 30 chemical contaminants between 2023 and 2025. This action provides EPA and other interested parties with scientifically valid data on the national occurrence of these contaminants in drinking water. Consistent with EPA’s PFAS Strategic Roadmap, UCMR 5 will provide new data that is needed to improve EPA’s 2 PFAS Notification and Response Levels issued by the California Division of Drinking Water can be found at: https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/pfas.html 3 The PFAS Strategic Roadmap: EPA’s Commitments to Action 2021-2024 can be found at: https://www.epa.gov/system/files/documents/2021-10/pfas-roadmap_final-508.pdf 4 EPA’s PFAS Strategic Roadmap: A Year of Progress can be found at: https://www.epa.gov/system/files/documents/2022- 11/PFAS%20Roadmap%20Progress%20Report_final_Nov%2017.pdf 5 42 USC Ch. 103: Comprehensive Environmental Response, Compensation, and Liability can be found at: https://uscode.house.gov/view.xhtml?path=/prelim@title42/chapter103&edition=prelim 6 The Fifth Unregulated Contaminant Monitoring Rule (UCMR 5); Program Overview Fact Sheet can be found at: https://www.epa.gov/system/files/documents/2022-02/ucmr5-factsheet.pdf PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 3 understanding of the frequency of 29 PFAS contaminants in the nation’s drinking water systems and at what concentrations they are found. LOCAL WATER SUPPLY IMPACTS FROM PFAS Currently, the City’s drinking water is not impacted by PFAS, largely because the City receives its drinking water from rural surface water sources, away from sources of contamination. PFAS contamination enters the environment at sites where PFAS are made, used, disposed of, or spilled. Studies have shown that PFAS contamination of groundwater increases with increasing urbanization. Once in groundwater, PFAS are easily transported large distances, tend to accumulate in groundwater, and can contaminate drinking water wells. Non-City wells within the Airport Area and adjacent areas around Buckley Road and Suburban Road have had positive detections of PFAS7. Groundwater sampling done as part of the City’s Prop 1 funded groundwater study showed levels of PFAS greater than the California Response Level in non-water-supply wells within City limits, adjacent to Highway 101 between Los Osos Valley Road and Madonna Road. The City’s only active water supply well, Pacific Beach Well, which has not been used since 2015, was tested and did not contain PFAS. As the City develops its groundwater program the Utilities Department will ensure that a groundwater sampling and monitoring program is developed to maximize the understanding of the local PFAS contamination, and that appropriate treatment technologies are implemented to ensure that PFAS contaminated drinking water is not delivered to the community. PFAS DETECTION IN WASTEWATER In 2020 and 2021, the City’s Water Resource Recovery Facility (WRRF) was required to complete four quarters of sampling for PFAS. Per the Statewide Investigative Order (WQ-2020-0015-DWQ), the WRRF’s influent, effluent, and biosolids were sampled and reported to the State Water Board’s Geotracker database. This statewide data collection study was completed for all wastewater treatment plants in California rated to treat flows above one million gallons per day. Results of the sampling indicated that the City had only trace concentrations of PFAS in biosolids material. Because PFAS are pervasive in consumer products, they can make their way into the wastewater stream via showering, dishwashing, clothes washing, and other activities, and are not always 7 The State Water Resources Control Board GeoTracker PFAS Map application can be found at: https://geotracker.waterboards.ca.gov/map/pfas_map Figure 2 - How PFAS collects in Sewage PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 4 attributable to drinking water contamination. In the City’s case, where PFAS is not present is drinking water, presence in biosolids is likely attributable to personal use of products containing PFAS. As drinking water standards for PFAS emerge, it is likely that PFAS standards for wastewater effluent and wastewater biosolids will also be developed. NEXT STEPS Utilities Department staff will remain proactive in communicating regarding local groundwater contamination and the work being done to ensure that drinking water provided to our community will not adversely impact public health. The talking points listed below reflect the current understanding of PFAS and will be updated as more information is available. TALKING POINTS: 1. The City’s drinking water is not currently impacted by PFAS, largely because the City receives its drinking water from rural surface water sources instead of groundwater wells underlying urban areas where PFAS generally accumulates. 2. The City will continue to monitor water, wastewater, and biosolids for PFAS, as required by EPA and State of California regulations. Figure 3 - Median California Biosolids Concentrations in Context PFAS IMPACTS TO CITY WATER AND WASTEWATER Page 5 3. When the City’s groundwater program is expanded, sampling, monitoring, and treatment of any PFAS contamination will be conducted prior to delivery of groundwater to the community. 4. While the EPA and State of California have not set actionable regulatory thresholds for PFAS in drinking water, they are in the process of developing them. The department will communicate with the public as these standards are finalized. 5. PFAS has been detected in groundwater within City limits and is prevalent in groundwater regionally, statewide, and nationally and is not a source of drinking water. 6. The City is not currently delivering groundwater and all of the City’s surface water supplies are free of PFAS contamination. 7. When groundwater wells are used, they will include treatment systems to remove groundwater contamination, including PFAS. 8. PFAS vs PCE vs TCE a. PFAS are a group of manufactured substances that are found in many different consumer, commercial, and industrial products (Teflon, GORE-TEX, cosmetics, non-stick cookware, firefighting foam 8, etc.). This makes it challenging to study and assess the potential human health and environmental risks. PFAS has been detected in groundwater from the airport west to Highway 101. B. PCE is a chemical widely used in dry-cleaning fabrics and metal degreasing operations. This is the chemical that has been detected in groundwater in the San Luis Valley groundwater subarea adjacent to San Luis Obispo Creek between downtown and Los Osos Valley Road and was the subject of the City’s recent groundwater project9. PCE will be removed before any use of local groundwater for municipal drinking water purposes. C. TCE is a chemical used mostly in industrial and commercial processes such as cleaning and furniture care products, arts and crafts spray coatings, and automotive care products like brake cleaners. TCE has been detected in groundwater in the area around Buckley Road10; however, it is not present in groundwater underlying the City, nor is it present in our municipal drinking water supplies. If you have questions, please feel free to reach out to Aaron Floyd, Utilities Director 8 The San Luis Obispo Fire Department no longer uses firefighting foam that contains PFAS. Foams in use by the San Luis Obispo Fire Department include PHOS-CHEK® WD881 (https://www.perimeter-solutions.com/wp- content/uploads/2021/08/PHOS-CHEK-WD881-EN-OSHA-WHMIS-GHS-SDS-2020-06-18.pdf) and SOLBERG® RE- HEALING™ RF3 (https://www.perimeter-solutions.com/wp- content/uploads/2021/06/PERI_Rehealing_RF3_3_FoamConcentrate_Datasheet_v1.pdf) 9 Information on the City of San Luis Obispo Groundwater Enhancement Project can be found at: https://www.slocity.org/government/department-directory/utilities-department/water/water- sources/groundwater 10 Information on the Central Coast Regional Water Quality Control Board investigation of trichloroethylene (TCE) in groundwater in the Buckley Road area can be found at: https://www.waterboards.ca.gov/centralcoast/water_issues/hot_topics/tce_pce_info/tce_pce_index.html PFAS Regulatory Landscape: Summary for California Municipal Water and Wastewater Agencies Background Per- and polyfluoroalkyl substances (PFAS) are persistent synthetic chemicals found across environmental media, known for their resistance to degradation and potential health risks. While the U.S. EPA has ramped up efforts, individual states, including California, are taking the lead in regulating PFAS across drinking water, groundwater, surface water, soil, air, fish, wildlife, biosolids, and consumer products. 1. National and State-Level Regulatory Trends • EPA Action: In April 2024, the EPA finalized a National Primary Drinking Water Regulation (NPDWR) for six PFAS compounds with enforceable Maximum Contaminant Levels (MCLs). Compliance monitoring is required by 2027, with public notification and treatment mandates for exceedances. • State Action: 30 states have existing PFAS drinking water guidance; 18 of these have enforceable MCLs. Many states are also advancing their own regulations across groundwater, surface water, soil, and biosolids. • Hazardous Designation: 21 states regulate PFAS under CERCLA/RCRA equivalents. The EPA has designated PFOA and PFOS as hazardous substances under CERCLA. 2. California-Specific Initiatives • Action Plan: California has a PFAS action plan and engages in multi-agency coordination with the State Water Board, OEHHA, and CalRecycle. • Sampling and Monitoring: The State Water Board is sampling over 9,000 water systems and has issued orders for monitoring PFAS at landfills, airports, and industrial dischargers. • Wastewater and Biosolids: California has investigated potential PFAS pathways through wastewater and is working with POTWs and DoD to monitor and mitigate contamination. A major focus is land application of biosolids. • Consumer Products: California restricts PFAS in juvenile products, food packaging, and textiles. 3. Key Environmental Media Regulations • Drinking Water: California adopted notification and response levels for PFOA, PFOS, and PFBS. It is preparing to implement EPA’s MCLs. • Groundwater and Surface Water: Monitoring and cleanup levels have been established based on toxicity assessments. New regulatory frameworks are anticipated. • Soil and Air: California uses screening levels based on EPA’s Regional Screening Levels and restricts PFAS in chrome plating emissions. • Fish & Wildlife: Fish advisories issued for PFAS-contaminated water bodies. • Biosolids: California is reviewing biosolid land application practices in light of PFAS risks. 4. Planning and Funding Considerations • Monitoring Compliance: Municipal systems must prepare to sample for the six regulated PFAS by 2027 and assess treatment options. • Public Communication: Risk communication is essential. Public education on PFAS sources, exposure routes, and mitigation actions should be incorporated into local outreach. • Funding Opportunities: Federal Bipartisan Infrastructure Law (BIL) funds are available for PFAS monitoring and treatment, especially for disadvantaged communities and private wells. • Infrastructure Impacts: WWTPs, landfills, and airports may face increased scrutiny. Planning for pre-treatment and source control is advisable. 5. Key Takeaways for Municipal Staff • Anticipate Regulatory Pressure: Expect increased oversight across water, wastewater, stormwater, and solid waste operations. • Engage in Source Identification: Establish local inventories of PFAS sources (e.g., industrial users, airports, landfills). • Coordinate Regionally: Participate in state and regional PFAS workgroups for information sharing and consistent messaging. • Stay Informed on Methodologies: Analytical methods (e.g., EPA 537.1, 533, 1633) and definitions of PFAS vary. Alignment with state and federal protocols is critical. Conclusion PFAS regulation is rapidly evolving, and municipal agencies in California must take a proactive stance. With statewide and federal mandates expanding, strategic investment in sampling, treatment, source control, and public communication will be essential for compliance and community trust. 57 From:Lehman, Chris Sent:Thursday, May 29, 2025 1:40 PM To:UT_Managers Subject:RE: PFAS Attachments:230123-PFAS Council Memo.pdf; ECOS PFAS Report_Executive Summary.docx Following up on the PFAS item from our agenda. Please find the following attached: 1) Utilities Department PFAS memo to City Council. A good introduction to PFAS, the actions the City has taken, and our current exposure. a. A version of this is summarized on the City’s website here: https://www.slocity.org/government/department-directory/utilities-department/water/water- treatment/water-quality b. Please direct any sewer questions from the public to Matt Anderson or myself and water questions to Jason Meeks. 2) Summary of Federal and State developments from the Environmental Council of the States (ECOS), published April 2025. a. I’ve summarized the key takeaways in the attached using ChatGPT. b. The full 250-page report is available here. Thanks, Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications c. -----Original Appointment----- From: Utilities <utilities@slocity.org> Sent: Wednesday, July 6, 2022 8:34 AM To: Utilities; UT_Managers Cc: Schwanemann, Keith; Stuckenberg, Serenity; Claxton, Christina; Lehman, Chris; Anderson, Matt; Meeks, Jason; Whittington, Shane; Beech, Ryan; Floyd, Aaron; Anderson, Kyle; Evans, Noah; McGrath, Patrick; Scott, Shawna; Teague, Nick; Boerman, Mychal; Henderson, Marcus; Parsons, Jake; Buckingham, Meg; Barcenas, Miguel; Aiello, Antonio; Ridgeway, Julie; Washbish, Ryley Subject: Staff Meeting When: Thursday, May 29, 2025 8:00 AM-10:00 AM (UTC-08:00) Pacific Time (US & Canada). Where: 879 Morro, Conference Room Utilities Staff Meeting (Web view) 58 This is the staff meeting that will occur on the third Thursday of every month. ________________________________________________________________________________ Microsoft Teams meeting Join on your computer or mobile app Click here to join the meeting Meeting ID: Download Teams | Join on the web Or call in (audio only) +1 209-645-4165,,543877151# United States, Stockton Phone Conference ID: Find a local number | Reset PIN Learn More | Meeting options ________________________________________________________________________________ 59 From:Anderson, Matt Sent:Wednesday, April 9, 2025 4:04 PM To:Keeling, Shanta@Waterboards Cc:Lehman, Chris; Keeling, Shanta@Waterboards Subject:Requested Sampling Frequency and Monitoring Locations Attachments:NPDES PERMIT CA0049224 2014_WDR_R3-2014-0033_City_SLO.pdf; Order R3-2024-0001.pdf Shanta, Good afternoon and I hope all is well this Wednesday afternoon. For data collected from 9/25/2014 to 8/31/2024, we sampled at the locations and frequency identified on pages E-3 , E-9 and E-10 of R3-2014-0033. 60 61 62 For data collected between 9/1/2024 and today, we sampled at the locations and frequency identified on pages E-4., E-5, E-19 and E-20 of R3-2024-0001. 63 64 65 66 Please call me or email me with any questions or follow up requests. Thanks, Matt Anderson Laboratory Manager 67 Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications ORDER NO. R3-2014-0033 NPDES NO. CA0049224 The following Discharger is subject to waste discharge requirements (WDRs) set forth in this Order: Table 1. Discharger Information Table 2. Discharge Location Table 3. Administrative Information I, Kenneth A. Harris Jr., Executive Officer, do hereby certify that this Order with all attachments is a full, true, and correct copy of an order adopted by the California Regional Water Quality Control Board, Central Coast Region on September 25, 2014. ________________________________________ Kenneth A. Harris Jr., Executive Officer Discharger City of San Luis Obispo Name of Facility Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Discharge Point Effluent Description Discharge Point Latitude (North) Discharge Point Longitude (West) Receiving Water 001 Advanced tertiary treated effluent 35º 14ʹ 40ʺ N 120º 40ʹ 45ʺ W San Luis Obispo Creek This Order was adopted on: September 25, 2014 This Order shall become effective on: December 1, 2014 This Order shall expire on: November 30, 2019 The Discharger shall file a Report of Waste Discharge as an application for reissuance of WDRs in accordance with title 23, California Code of Regulations, and an application for reissuance of a National Pollutant Discharge Elimination System (NPDES) permit no later than: June 3, 2019 The U.S. Environmental Protection Agency (U.S. EPA) and the California Regional Water Quality Control Board, Central Coast Region have classified this discharge as follows: Major Discharge CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ORDER 2 Contents I. Facility Information ........................................................................................................................ 3 II. Findings ........................................................................................................................................ 3 III. Discharge Prohibitions .................................................................................................................. 3 IV. Effluent Limitations and Discharge Specifications ......................................................................... 4 A. Effluent Limitations – Discharge Point 001 ............................................................................. 4 1. Final Effluent Limitations – Discharge Point 001 ................................................................ 4 2. Interim Effluent Limitations – Not Applicable ...................................................................... 5 B. Land Discharge Specifications – Not Applicable .................................................................... 5 C. Recycling Specifications ........................................................................................................ 5 V. Receiving Water Limitations .......................................................................................................... 5 A. Surface Water Limitations ...................................................................................................... 5 B. Groundwater Limitations ........................................................................................................ 8 VI. Provisions ..................................................................................................................................... 9 A. Standard Provisions ............................................................................................................... 9 B. Monitoring and Reporting Program (MRP) Requirements ...................................................... 9 C. Special Provisions.................................................................................................................. 9 1. Reopener Provisions ......................................................................................................... 9 2. Special Studies, Technical Reports and Additional Monitoring Requirements .................... 9 3. Best Management Practices and Pollution Prevention ..................................................... 11 4. Construction, Operation and Maintenance Specifications ................................................ 13 5. Special Provisions for Municipal Facilities (POTWs Only) ................................................ 13 6. Other Special Provisions ................................................................................................. 15 7. Compliance Schedules – Not Applicable ......................................................................... 15 VII. Compliance Determination .......................................................................................................... 15 Tables Table 1. Discharger Information ............................................................................................................. 1 Table 2. Discharge Location .................................................................................................................. 1 Table 3. Administrative Information ........................................................................................................ 1 Table 4. Effluent Limitations ................................................................................................................... 4 Table 6. Organic Substances Water Quality Objectives ........................................................................ 7 Table 7. Surface Water Quality Objectives ............................................................................................ 7 Table 8. Groundwater Objectives .......................................................................................................... 8 Table 9. Toxicity Reduction Evaluation Schedule ................................................................................ 10 Attachments Attachment A – Definitions .................................................................................................................. A-1 Attachment B – Map ........................................................................................................................... B-1 Attachment C – Flow Schematic .........................................................................................................C-1 Attachment D – Standard Provisions ..................................................................................................D-1 Attachment E – Monitoring and Reporting Program ............................................................................ E-1 Attachment F – Fact Sheet ................................................................................................................. F-1 CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 3 I. FACILITY INFORMATION Information describing the City of San Luis Obispo Water Reclamation Facility (Facility) is summarized in Table 1 and in sections I and II of the Fact Sheet (Attachment F). Section I of the Fact Sheet also includes information regarding the Facility’s permit application. II. FINDINGS The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: A. Legal Authorities. This Order serves as WDRs pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA) and implementing regulations adopted by the U.S. EPA and chapter 5.5, division 7 of the Water Code (commencing with section 13370). It shall serve as an NPDES permit for point source discharges from this facility to surface waters. B. Background and Rationale for Requirements. The Central Coast Water Board developed the requirements in this Order based on information submitted as part of the application, through monitoring and reporting programs, and other available information. The Fact Sheet (Attachment F), which contains background information and rationale for the requirements in this Order, is hereby incorporated into and constitutes Findings for this Order. Attachments A through E are also incorporated into this Order. C. Provisions and Requirements Implementing State Law. The provisions/requirements in subsections IV.B, IV.C, V.B, and VI.C are included to implement state law only. These provisions/requirements are not required or authorized under the federal CWA; consequently, violations of these provisions/requirements are not subject to the enforcement remedies that are available for NPDES violations. D. Notification of Interested Parties. The Central Coast Water Board has notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and has provided them with an opportunity to submit their written comments and recommendations. Details of the notification are provided in the Fact Sheet. E. Consideration of Public Comment. The Central Coast Water Board, in a public meeting, heard and considered all comments pertaining to the discharge. Details of the public hearing are provided in the Fact Sheet. THEREFORE, IT IS HEREBY ORDERED that this Order supersedes Order No. R3-2002-0043, modified March 25, 2005, except for enforcement purposes, and, in order to meet the provisions contained in division 7 of the Water Code (commencing with section 13000) and regulations adopted thereunder and the provisions of the CWA and regulations and guidelines adopted thereunder, the Discharger shall comply with the requirements in this Order. This action in no way prevents the Central Coast Water Board from taking enforcement action for past violations of the previous Order. III. DISCHARGE PROHIBITIONS A. The discharge of treated wastewater at a location other than 35º 14' 40" N. Latitude, 120º 40' 45" W. Longitude, unless permitted by other waste discharge requirements or NPDES permit, is prohibited. B. Discharge to San Luis Obispo Creek of wastewaters containing bentazon, molinate, or thiobencarb is prohibited. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 4 IV. EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS A. Effluent Limitations – Discharge Point 001 1. Final Effluent Limitations – Discharge Point 001 a. The Discharger shall maintain compliance with the following effluent limitations at Discharge Point 001, with compliance measured at Monitoring Location EFF-001 as described in the Monitoring and Reporting Program (MRP) Attachment E: Table 4. Effluent Limitations Parameter Units Effluent Limitations Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Biochemical Oxygen Demand 5-day @ 20°C [1] mg/L 10 30 50 -- -- lbs/day 425 1,275 2,125 -- -- Total Suspended Solids [1] mg/L 10 30 75 -- -- lbs/day 425 1,275 3,190 -- -- Oil and Grease mg/L 5 -- 10 -- -- pH standard units -- -- -- 6.5 8.3 Chlorodibromomethane µg/L 0.40 -- 1.0 -- -- Dichlorobromomethane µg/L 0.56 -- 1.0 -- -- N-Nitrosodimethylamine µg/L 0.00069 -- 0.0014 -- -- Dissolved Oxygen mg/L -- -- -- 4.0 -- Nitrate (as N) mg/L 10 -- -- -- -- Settleable Solids mL/L 0.1 -- -- -- -- Chlorine Residual mg/L -- -- ND [3] -- -- [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 6.5 – 8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 6.5 – 8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0 – 9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 6.5 – 8.3 at all times, measured daily) [3] ND = less than 0.1 mg/L. Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. b. Toxicity: Discharges at Discharge Point 001, with compliance measured at Monitoring Location EFF-001 as described in the Monitoring and Reporting Program (Attachment E), shall not contain chronic toxicity at a level that would cause or contribute to toxicity in the receiving water. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, or any other relevant measure of the health of an organism population or community. Compliance with this limit shall be determined by analysis of indicator organisms and toxicity tests as described in the MRP. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 5 c. Coliform: i. The fecal colif orm concentrations shall not exceed a median of 2.2 MPN/100 mL as determined from the last 7 days of sampling results for which analyses have been completed; ii. No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30-day period; iii. No sample shall exceed 240 MPN/100 mL total coliform. d. Effluent flow: The average dry weather daily discharge flow shall not exceed 5.1 million gallons per day (MGD). 2. Interim Effluent Limitations – Not Applicable B. Land Discharge Specifications – Not Applicable C. Recycling Specifications The Discharger currently produces and distributes tertiary treated recycled water within the City of San Luis Obispo. Recycled water is regulated under the City’s existing Master Reclamation Permit Order No. R3-2003-081, and therefore no additional specifications are applicable under this permit. V. RECEIVING WATER LIMITATIONS A. Surface Water Limitations Receiving water limitations are based on water quality objectives contained in the Basin Plan, are consistent with the State Implementation Policy, and are a required part of this Order. The discharge shall not cause a violation of the following receiving water limitations in San Luis Obispo Creek. The Central Coast Water Board may require the Discharger to investigate the cause of exceedance(s) in the receiving water to determine whether the Discharger caused any water condition that exceeds the following receiving water limitations. 1. Waters shall be free of coloration that causes nuisance or adversely affects beneficial uses. Coloration attributable to materials of waste origin shall not be greater than 15 units or 10 percent above natural background color, whichever is greater. 2. Waters shall not contain taste or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, that cause nuisance, or that adversely affect beneficial uses. 3. Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 4. Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. 5. Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. 6. Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 6 7. Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses. 8. The suspended sediment load and suspended sediment discharge rate to surface waters shall not be altered in such a manner as to cause nuisance or adversely affect beneficial uses. 9. Concentrations of toxic metals and inorganic chemicals in waters shall not be increased in such a manner that may adversely affect beneficial uses. 10. Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Increase in turbidity attributable to controllable water quality factors shall not exceed the following limits: a. Where natural turbidity is between 0 and 50 Natural Turbidity Units (NTUs), increases shall not exceed 20 percent. b. Where natural turbidity is between 50 and 100 NTUs, increases shall not exceed 10 NTU. c. Where natural turbidity is greater than 100 NTUs, increases shall not exceed 10 percent. d. Turbidity to exceed 5 NTU when the Creek contains no natural flow. 11. The pH value shall not be depressed below 7.0 nor raised above 8.3. The change in normal ambient pH levels shall not exceed 0.5 units. 12. Dissolved oxygen concentrations in receiving waters shall not be reduced below 7.0 mg/L at any time. 13. Effluent discharged shall not cause the receiving water temperature to increase more than 5° F above receiving water temperature. If, due to the Creek’s low temperature as determined by early-morning monitoring, the discharge causes the Creek’s temperature increase to exceed the limit, the Discharger must ensure the discharge shall not cause the receiving water to exceed 72.5° F (22.5° C). The Discharger shall monitor the Creek again four hours after discovering the exceedance and shall report both results to the Executive Officer in the monthly self-monitoring report. 14. Waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same water body in areas unaffected by the waste discharge. 15. The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/L (as N) in the receiving water. 16. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect the beneficial uses of the receiving water. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life. For waters where existing concentrations are presently nondetectable or where beneficial uses would be impaired by concentrations in excess of nondetectable levels, total identifiable chlorinated hydrocarbon pesticides shall not be present at concentrations detectable within the accuracy of analytical methods as prescribed in Standard Methods for the Examination of Water and Wastewater, latest edition, or other equivalent methods approved by the Executive Officer. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 7 17. Waters shall not contain organic substances in concentrations greater than the following: Table 6. Organic Substances Water Quality Objectives Parameter Water Quality Objective Methylene Blue Activated Substances 0.2 mg/L Phenols 1.0 µg/L PCBs [1] 0.3 µg/L Phthalate Esters 0.002 µg/L [1] PCBs refer to the sum of PCB 1016, 1221, 1232, 1242, 1248, 1254, and 1260. 18. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or that result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstance shall receiving waters contain concentrations of radionuclides in excess of the maximum contaminant levels (MCLs) for radioactivity presented in Table 4 of Title 22 California Code of Regulations, Division 4, Chapter 15, Article 5. 19. Receiving waters shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for Organic Chemicals) of Title 22 California Code of Regulations, Division 4, Chapter 15. 20. Receiving waters shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural beneficial use. Interpretation of adverse effects shall be derived from guidelines of the University of California Agricultural Extension Service guidelines presented in Section III, Table 3-3 of the Basin Plan. 21. Receiving waters shall not contain concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in Section III, Table 3-4 of the Basin Plan. Salt concentrations for irrigation waters shall be controlled through implementation of the anti-degradation policy to the effect that mineral constituents of currently or potentially usable waters shall not be increased. 22. Receiving waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife in excess of the levels presented in Section III, Table 3- 5 of the Basin Plan. 23. Fecal coliform concentration, based on a minimum of not fewer than five samples for any 30-day period, shall not exceed a log mean of 200 organisms/100 mL, nor shall more than 10 percent of samples collected during any 30-day period exceed 400 organisms/100 mL. 24. Discharges shall not cause receiving water to exceed the following water quality objectives specifically identified for the San Luis Obispo Creek sub-area (Estero Bay sub- basin) by Table 3-7 of the Basin Plan, shown below in Table 7. Table 7. Surface Water Quality Objectives Constituent Annual Running Mean(1), mg/L Total Dissolved Solids 650 Chloride 100 Sulfate 100 Boron 0.2 Sodium 50 CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 8 (1) Compliance shall be measured by comparison to an annual running mean of the past four quarterly sampling events. B. Groundwater Limitations Activities at the Facility shall not cause exceedance/deviation from the following water quality objectives for groundwater established by the Basin Plan. The Central Coast Water Board may require the Discharger to investigate the cause of exceedances in the groundwater before determining whether the Discharger caused any water condition that exceeds the following groundwater limitations. 1. Groundwater shall not contain taste- or odor-producing substances in concentrations that adversely affect beneficial uses. 2. The Discharger shall not cause a statistically significant increase of mineral constituent concentrations in underlying groundwaters as determined by comparison of samples collected from wells located up-gradient and down-gradient of the waters affected by the discharge. 3. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or that result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstances shall groundwater contain concentrations of radionuclides in excess of the MCLs for radioactivity presented in Table 4 of Title 22 California Code of Regulations, Division 4, Chapter 15, Article 5. 4. The median concentration of coliform organisms in groundwater, over any seven-day period, shall be less than 2.2 organisms/100 mL. 5. Groundwater shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for Organic Chemicals) of Title 22 California Code of Regulations, Division 4, Chapter 15. 6. Groundwater shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural supply beneficial use. Interpretation of adverse effects shall be as described in University of California Agricultural Extension Service guidelines provided in Table 3-3 of the Basin Plan. 7. Groundwater used for irrigation and livestock watering shall not exceed concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in Section III, Table 3-4 of the Basin Plan. 8. Groundwater shall not contain pollutants at concentrations greater than the following established in Table 3-8 of the Basin Plan for groundwaters within the San Luis Obispo Creek sub-area (Estero Bay sub-basin). Table 8. Groundwater Objectives Constituent Median[1], mg/L Total Dissolved Solids 900 Chloride 200 Sulfate 100 Boron 0.2 Sodium 50 Nitrogen (as N) 5 [1] Objectives shown are median values based on data averages; objectives are based on preservation of existing water quality enhancement believed attainable following control of point sources. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 9 VI. PROVISIONS A. Standard Provisions 1. The Discharger shall comply with all Standard Provisions included in Attachment D of this Order. 2. The Discharger shall comply with the following provision: a. Before changing the point of discharge, place of use, or purpose of use of treated wastewater that results in a decrease of flow in any portion of an inland watercourse, in any way, the Discharger shall file a petition with the State Water Resources Control Board (State Water Board), Division of Water Rights, and receive approval for such a change. (Water Code section 1211.) B. Monitoring and Reporting Program (MRP) Requirements Pursuant to CWC sections 13267 and 13383, the Discharger shall comply with the Monitoring and Reporting Program (MRP), and future revisions thereto, in Attachment E of this Order, and all notification and general reporting requirements throughout this Order and Attachment D. Where notification or general reporting requirements conflict with those stated in the MRP (e.g., annual report due date), the Discharger shall comply with the MRP requirements. All monitoring shall be conducted according to 40 C.F.R. part 136, Guidelines Establishing Test Procedures for Analysis of Pollutants. The Discharger is required to provide these technical or monitoring reports because it is the owner and operator responsible for the waste discharge and compliance with this Order. The Central Coast Water Board needs the information to determine the Discharger’s compliance with this Order, assess the need for further investigation and/or enforcement action, and to protect public health and safety and the environment. C. Special Provisions 1. Reopener Provisions This permit may be reopened and modified in accordance with NPDES regulations at 40 C.F.R. parts 122 and 124, as necessary, to include additional conditions or limitations based on newly available information or to implement any USEPA approved, new, State WQO. 2. Special Studies, Technical Reports and Additional Monitoring Requirements a. Toxicity Reduction Requirements As indicated in section V.D of the MRP, when acute toxicity is detected in the effluent or chronic toxicity is detected greater than a chronic toxicity trigger of 1 TUc, and the discharge is continuing, the Discharger shall resample immediately, retest, and report the results to the Executive Officer, who will determine whether to initiate an enforcement action, require a Toxicity Reduction Evaluation (TRE) in accordance with the Discharger’s TRE Workplan, or implement other measures. A TRE is a study conducted in a step-wise process designed to identify the causative agents of effluent or ambient toxicity, isolate the sources of toxicity, evaluate the effectiveness of toxicity control options, and then confirm the reduction in toxicity. The first steps of the TRE consist of the collection of data relevant to the toxicity, including additional toxicity testing, an evaluation of facility operations and maintenance practices, and best management practices. A Toxicity Identification Evaluation (TIE) may be required as part of the TRE, if appropriate. A CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 10 TIE is a set of procedures to identify the specific chemical(s) responsible for toxicity. These procedures are performed in three phases - characterization, identification, and confirmation using aquatic organism toxicity tests. The TRE shall include all reasonable steps to identify the source of toxicity. The Discharger shall take all reasonable steps to reduce toxicity to the required level once the source of toxicity is identified. The Discharger shall maintain a TRE Workplan, which describes steps that the Discharger intends to follow in the event that a toxicity effluent limitation or toxicity trigger established by this Order is exceeded in the discharge. The workplan shall be prepared in accordance with current technical guidance and reference material, including EPA/600/2-88/062, and shall include, at a minimum: i. Actions that will be taken to investigate/identify the causes/sources of toxicity; ii. Actions that will be evaluated to mitigate the impact of the discharge, to correct the noncompliance, and/or to prevent the recurrence of acute or chronic toxicity (this list of action steps may be expanded, if a TRE is undertaken); and iii. A schedule under which these actions will be implemented. When monitoring measures toxicity in the effluent above a limitation or toxicity trigger established by this Order, if the discharge is continuing, the Discharger shall resample immediately, and retest for acute or chronic toxicity. Results of an initial failed test and results of subsequent monitoring shall be reported to the Executive Officer as soon as possible following receipt of monitoring results. The Executive Officer will determine whether to initiate enforcement action, whether to require the Discharger to implement a TRE, or to implement other measures. When the Executive Officer requires the Discharger to conduct a TRE, the TRE shall be conducted giving due consideration to guidance provided by the USEPA’s Toxicity Reduction Evaluation Procedures, Phases 1, 2, and 3 (USEPA document Nos. EPA 600/R-91/003, 600/R-92/080, and 600/R-92/081, respectively). A TRE, if necessary, shall be conducted in accordance with the following schedule. Table 9. Toxicity Reduction Evaluation Schedule Action Step When Required Take all reasonable measures necessary to immediately reduce toxicity, where the source is known. Within 24 hours of identification of noncompliance. Submit to the Executive Officer a TRE study plan describing the toxicity reduction procedures to be employed Within 60 days of identification of noncompliance. Initiate the TRE in accordance with the Workplan Within 7 days of notification by the Executive Officer. Conduct the TRE following the procedures in the Workplan. Within the period specified in the Workplan (not to exceed one year, without an approved Workplan). Submit the results of the TRE, including summary of findings, required corrective action, and all results and data. Within 60 days of the completion of the TRE. Implement corrective actions to meet Permit limits and conditions. To be determined by the Executive Officer. Return to regular monitoring after implementing corrective measures and approval by the Executive Officer. To be determined by the Executive Officer. b. Facilities Evaluation CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 11 Based on Discharger reports, the Facility is operating at 88% of its design capacity for flow. Based on that data, it appears that the monthly average daily flow will or may reach design capacity during the term of this permit. Pursuant to Central Coast Standard Provisions, the Discharger shall evaluate the need for future expansion of the Facility to accommodate future growth within the City of San Luis Obispo. The evaluation shall quantify future flows to the plant from indirect dischargers, California State Polytechnic University and San Luis Obispo County Airport, and future annexations to the City of San Luis Obispo. This evaluation shall be completed as part of the Facilities Plan during the term of this permit and submitted to the Central Coast Water Board. c. Effluent pH Evaluation The Discharger shall complete an Effluent pH Evaluation by February 1, 2016 to assess opportunities for effluent pH adjustments consistent with more stringent Basin Plan water quality objectives for receiving water (i.e., 7.0-8.3 standard units), impact on receiving water and environment, cost to pH adjust, and expected frequency and duration that effluent pH would drop below 7.0 s.u. under current operations. Central Coast Water Board staff will review the data to consider whether a more stringent pH effluent limit would indeed be more protective of water quality objectives, or if existing pH effluent limits are adequately protective of receiving water quality objectives. 3. Best Management Practices and Pollution Prevention a. Salt and Nutrient Management Program i. The Discharger shall develop and implement an ongoing Salts Management Program dedicated to minimizing the discharge of salts to and attainment of applicable WQOs for salts in San Luis Obispo Creek sub-basin of the Estero Bay Drainage Basin. Additionally, the Discharger shall develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable WQOs for nutrients in the same basin. ii. Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. iii. Nutrient reduction measures shall focus on optimizing wastewater treatment processes for nitrification and denitrification, or other means of nitrogen removal. Reduction measures may also include source control (non-human waste from commercial and industrial sources) as appropriate. iv. As part of the salts and nutrients management program, the Discharger shall submit an annual report of salts and nutrients reduction efforts. This salts and nutrients management report shall be included as part of the annual report described in the MRP (Attachment E). The report shall be submitted by February 15, and shall include, as appropriate: (a) Salt Component (1) Calculations of annual salt mass discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 12 (2) Analysis of wastewater evaporation/salt concentration effects; (3) Analysis of groundwater monitoring results for salts constituents and associated trends; (4) Analysis of potential impacts of salt loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); (5) A summary of existing salt reduction measures; and (6) Recommendations and time schedules for implementation of any additional salt reduction measures; (b) Nutrient Component (1) Calculations of annual nitrogen mass (for all identified species) discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; (2) Analysis of wastewater treatment facility ability to facilitate nitrification and denitrification, or other means of nitrogen removal; (3) Analysis of groundwater monitoring results for nitrogen constituents and trends; (4) Analysis of potential impacts of nitrogen loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); (5) A summary of existing nitrogen loading reduction measures; and (6) Recommendations and time schedules for implementation of any additional nitrogen loading reduction measures. v. As an alternative to the Salt and Nutrient Management Program requirements described above, upon Executive Officer approval, the Discharger may submit documentation and summary of participation in a regional salts and nutrients management plan implemented under the provisions of State Water Board Resolution No. 2009-0011 (Recycled Water Policy). b. Pollutant Minimization Program The Discharger shall develop and conduct a Pollutant Minimization Program (PMP) as further described below when there is evidence (e.g., sample results reported as DNQ when the effluent limitation is less than the MDL, sample results from analytical methods more sensitive than those methods required by this Order, presence of whole effluent toxicity, health advisories for fish consumption, results of benthic or aquatic organism tissue sampling) that a priority pollutant is present in the effluent above an effluent limitation and either: i. A sample result is reported as DNQ and the effluent limitation is less than the RL; or ii. A sample result is reported as ND and the effluent limitation is less than the MDL, using definitions described in Attachment A and reporting protocols described in MRP section X.B.4. The PMP shall include, but not be limited to, the following actions and submittals acceptable to the Central Coast Water Board: CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 13 iii. An annual review and semi-annual monitoring of potential sources of the reportable priority pollutant(s), which may include fish tissue monitoring and other bio-uptake sampling; iv. Quarterly monitoring for the reportable priority pollutant(s) in the influent to the wastewater treatment system; v. Submittal of a control strategy designed to proceed toward the goal of maintaining concentrations of the reportable priority pollutant(s) in the effluent at or below the effluent limitation; vi. Implementation of appropriate cost-effective control measures for the reportable priority pollutant(s), consistent with the control strategy; and vii. An annual status report that shall be sent to the Central Coast Water Board including: (a) All PMP monitoring results for the previous year; (b) A list of potential sources of the reportable priority pollutant(s); (c) A summary of all actions undertaken pursuant to the control strategy; and (d) A description of actions to be taken in the following year. 4. Construction, Operation and Maintenance Specifications The Facility shall be operated as specified under Standard Provision I.A.4 of Attachment D. 5. Special Provisions for Municipal Facilities (POTWs Only) a. Biosolids Management i. The handling, treatment, use, management, and disposal of sludge and solids derived from wastewater treatment must comply with applicable provisions of CWA Section 405 and USEPA regulations at 40 C.F.R. p arts 257, 258, 501, and 503, including all monitoring, record keeping, and reporting requirements. ii. Sludge and wastewater solids must be disposed of in a municipal solid waste landfill, reused by land application, or disposed of in a sludge-only landfill in accordance with 40 C.F.R. parts 258 and 503 and Title 23, Chapter 15 of the CCR. If the Discharger desires to dispose of solids and/or sludge in a different manner, a request for permit modification must be submitted to the USEPA and to the Central Coast Water Board at least 180 days prior to beginning the alternative means of disposal. iii. Sludge that is disposed of in a municipal solid waste landfill must meet the requirements of 40 C.F.R. part 258 pertaining to providing information to the public. In the annual self-monitoring report, the Discharger shall include the amount of sludge placed in the landfill as well as the landfill to which it was sent. iv. All requirements of 40 C.F.R. part 503 and 23 CCR Chapter 15 are enforceable whether or not the requirements of those regulations are stated in an NPDES permit or any other permit issued to the Discharger. v. The Discharger shall take all reasonable steps to prevent and minimize any sludge use or disposal in violation of this Order that has a likelihood of adversely affecting human health or the environment. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 14 vi. Solids and sludge treatment, storage, and disposal or reuse shall not create a nuisance, such as objectionable odors or flies, and shall not result in groundwater contamination. vii. The solids and sludge treatment and storage site shall have adequate facilities to divert surface water runoff from adjacent areas to protect the boundaries of the site from erosion, and to prevent drainage from the treatment and storage site. Adequate protection is defined as protection, at the minimum, from a 100-year storm and protection from the highest possible tidal stage that may occur. viii. The discharge of sewage sludge and solids shall not cause waste material to be in position where it is, or can be, conveyed from the treatment and storage sites and deposited in waters of the State. ix. The Discharger shall submit an annual report to the USEPA and the Central Coast Water Board containing monitoring results and pathogen and vector attraction reduction requirements, as specified by 40 C.F.R. part 503. The Discharger shall also report the quantity of sludge removed from the Facility and the disposal method. This self-monitoring report shall be postmarked by February 19th of each year and report for the period of the previous calendar year. b. Pretreatment The Discharger shall be responsible for the performance of all pretreatment requirements contained in 40 C.F.R. and shall be subject to enforcement actions, penalties, fines, and other remedies by the USEPA, or other appropriate parties, as provided in the CWA, as amended (33 USA 1351 et seq.). The Discharger shall implement and enforce its Approved Publicly Owned Treatment Works (POWT) Pretreatment Program. Implementation of the Discharger’s Approved POTW Pretreatment Program is hereby made an enforceable condition of this permit. USEPA may initiate enforcement action against an industrial user for non- compliance with applicable standards and requirements as provided in the CWA. The Discharger shall enforce the requirements promulgated under Sections 307 (b), (c), & (d) and 402 (b) of the CWA. The Discharger shall cause industrial users subject to Federal Categorical Standards to achieve compliance no later than the date specified in those requirements, or, in the case of a new industrial user, upon commencement of the discharge. The Discharger shall perform the pretreatment functions as required in 40 C.F.R. 403, including, but not limited to: i. Implement necessary legal authorities as provided in 40 C.F.R 403.8 (f)(1); ii. Enforcement of pretreatment requirements under 40 C.F.R. 403.5 and 403.6; iii. Implement the programmatic functions as provided in 40 C.F.R. 403.8 (f)(2); and iv. Provide the requisite funding and personnel to implement the pretreatment program as provided in 40 C.F.R. 403.8 (f)(3). The Discharger shall submit annually a report to the USEPA – Region 9, the Central Coast Water Board, and the State Water Board describing the Discharger’s pretreatment activities over the previous twelve months. If the Discharger violates this Order’s pretreatment conditions or requirements, it shall also include reasons CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 15 for noncompliance, and a statement how and when it shall comply. This annual report is due by February 1st of each year and shall contain, but not be limited to, the contents described in the “Pretreatment Reporting Requirements” contained in the Monitoring and Reporting Program (Attachment E). The Discharger shall comply, and ensure affected “indirect dischargers” comply with Paragraph II.D.1 of the “Standard Provisions and Reporting Requirements.” 6. Other Special Provisions a. Discharges of Storm Water. For the control of storm water discharged from the site of the wastewater treatment and disposal facilities, if applicable, the Discharger shall seek authorization to discharge under and meet the requirements of the State Water Board’s Water Quality Order 97-03-DWQ, NPDES General Permit No. CAS0000001, Waste Discharge Requirements for Discharges of Storm Water Associated with Industrial Activities Excluding Construction Activities. b. Statewide General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order 2006-0003-DWQ). This General Permit, adopted on May 2, 2006, is applicable to all “federal and State agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publically owned treatment facility in the State of California.” The purpose of the General Permit is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger has obtained coverage under the General Permit. 7. Compliance Schedules – Not Applicable VII. COMPLIANCE DETERMINATION Compliance with the effluent limitations contained in Section IV of this Order will be determined as specified below: A. General. Compliance with effluent limitations for reportable pollutants shall be determined using sample reporting protocols defined in the MRP and Attachment A of this Order. For purposes of reporting and administrative enforcement by the Central Coast Water Board and State Water Boards, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the reportable pollutant in the monitoring sample is greater than the effluent limitation and greater than or equal to the reported Minimum Level (ML). B. Multiple Sample Data. When determining compliance with an average monthly effluent limit and more than one sample result is available in a month, the Discharger shall compute the arithmetic mean unless the data set contains one or more reported determinations “Detected, but Not Quantified” (DNQ) or “Not Detected” (ND). In those cases, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ-determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an even number CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 LIMITATIONS AND DISCHARGE REQUIREMENTS 16 of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT A – DEFINITIONS A-1 A. ATTACHMENT A – DEFINITIONS Arithmetic Mean (µ) Also called the average, is the sum of measured values divided by the number of samples. For ambient water concentrations, the arithmetic mean is calculated as follows: Arithmetic mean = µ = Σx / n where: Σx is the sum of the measured ambient water concentrations, and n is the number of samples. Average Monthly Effluent Limitation (AMEL) The highest allowable average of daily discharges over a calendar month, calculated as the sum of all daily discharges measured during a calendar month divided by the number of daily discharges measured during that month. Average Weekly Effluent Limitation (AWEL) The highest allowable average of daily discharges over a calendar week (Sunday through Saturday), calculated as the sum of all daily discharges measured during a calendar week divided by the number of daily discharges measured during that week. Bioaccumulative Those substances taken up by an organism from its surrounding medium through gill membranes, epithelial tissue, or from food and subsequently concentrated and retained in the body of the organism. Carcinogenic Pollutants are substances that are known to cause cancer in living organisms. Coefficient of Variation (CV) CV is a measure of the data variability and is calculated as the estimated standard deviation divided by the arithmetic mean of the observed values. Daily Discharge Daily Discharge is defined as either: (1) the total mass of the constituent discharged over the calendar day (12:00 am through 11:59 pm) or any 24-hour period that reasonably represents a calendar day for purposes of sampling (as specified in the permit), for a constituent with limitations expressed in units of mass or; (2) the unweighted arithmetic mean measurement of the constituent over the day for a constituent with limitations expressed in other units of measurement (e.g., concentration). The daily discharge may be determined by the analytical results of a composite sample taken over the course of one day (a calendar day or other 24-hour period defined as a day) or by the arithmetic mean of analytical results from one or more grab samples taken over the course of the day. For composite sampling, if 1 day is defined as a 24-hour period other than a calendar day, the analytical result for the 24-hour period will be considered as the result for the calendar day in which the 24-hour period ends. Detected, but Not Quantified (DNQ) DNQ are those sample results less than the RL, but greater than or equal to the laboratory’s MDL. Sample results reported as DNQ are estimated concentrations. Dilution Credit Dilution Credit is the amount of dilution granted to a discharge in the calculation of a water quality- based effluent limitation, based on the allowance of a specified mixing zone. It is calculated from the CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT A – DEFINITIONS A-2 dilution ratio or determined through conducting a mixing zone study or modeling of the discharge and receiving water. Effluent Concentration Allowance (ECA) ECA is a value derived from the water quality criterion/objective, dilution credit, and ambient background concentration that is used, in conjunction with the coefficient of variation for the effluent monitoring data, to calculate a long-term average (LTA) discharge concentration. The ECA has the same meaning as waste load allocation (WLA) as used in U.S. EPA guidance (Technical Support Document For Water Quality-based Toxics Control, March 1991, second printing, EPA/505/2-90-001). Enclosed Bays Enclosed Bays means indentations along the coast that enclose an area of oceanic water within distinct headlands or harbor works. Enclosed bays include all bays where the narrowest distance between the headlands or outermost harbor works is less than 75 percent of the greatest dimension of the enclosed portion of the bay. Enclosed bays include, but are not limited to, Humboldt Bay, Bodega Harbor, Tomales Bay, Drake’s Estero, San Francisco Bay, Morro Bay, Los Angeles-Long Beach Harbor, Upper and Lower Newport Bay, Mission Bay, and San Diego Bay. Enclosed bays do not include inland surface waters or ocean waters. Estimated Chemical Concentration The estimated chemical concentration that results from the confirmed detection of the substance by the analytical method below the ML value. Estuaries Estuaries means waters, including coastal lagoons, located at the mouths of streams that serve as areas of mixing for fresh and ocean waters. Coastal lagoons and mouths of streams that are temporarily separated from the ocean by sandbars shall be considered estuaries. Estuarine waters shall be considered to extend from a bay or the open ocean to a point upstream where there is no significant mixing of fresh water and seawater. Estuarine waters included, but are not limited to, the Sacramento-San Joaquin Delta, as defined in Water Code section 12220, Suisun Bay, Carquinez Strait downstream to the Carquinez Bridge, and appropriate areas of the Smith, Mad, Eel, Noyo, Russian, Klamath, San Diego, and Otay rivers. Estuaries do not include inland surface waters or ocean waters. Inland Surface Waters All surface waters of the state that do not include the ocean, enclosed bays, or estuaries. Instantaneous Maximum Effluent Limitation The highest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous maximum limitation). Instantaneous Minimum Effluent Limitation The lowest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous minimum limitation). Maximum Daily Effluent Limitation (MDEL) The highest allowable daily discharge of a pollutant, over a calendar day (or 24-hour period). For pollutants with limitations expressed in units of mass, the daily discharge is calculated as the total mass of the pollutant discharged over the day. For pollutants with limitations expressed in other units of measurement, the daily discharge is calculated as the arithmetic mean measurement of the pollutant over the day. Median CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT A – DEFINITIONS A-3 The middle measurement in a set of data. The median of a set of data is found by first arranging the measurements in order of magnitude (either increasing or decreasing order). If the number of measurements (n) is odd, then the median = X(n+1)/2. If n is even, then the median = (Xn/2 + X(n/2)+1)/2 (i.e., the midpoint between the n/2 and n/2+1). Method Detection Limit (MDL) MDL is the minimum concentration of a substance that can be measured and reported with 99 percent confidence that the analyte concentration is greater than zero, as defined in in 40 C.F.R. part 136, Attachment B, revised as of July 3, 1999. Minimum Level (ML) ML is the concentration at which the entire analytical system must give a recognizable signal and acceptable calibration point. The ML is the concentration in a sample that is equivalent to the concentration of the lowest calibration standard analyzed by a specific analytical procedure, assuming that all the method specified sample weights, volumes, and processing steps have been followed. Mixing Zone Mixing Zone is a limited volume of receiving water that is allocated for mixing with a wastewater discharge where water quality criteria can be exceeded without causing adverse effects to the overall water body. Not Detected (ND) Sample results which are less than the laboratory’s MDL. Persistent Pollutants Persistent pollutants are substances for which degradation or decomposition in the environment is nonexistent or very slow. Pollutant Minimization Program (PMP) PMP means waste minimization and pollution prevention actions that include, but are not limited to, product substitution, waste stream recycling, alternative waste management methods, and education of the public and businesses. The goal of the PMP shall be to reduce all potential sources of a priority pollutant(s) through pollutant minimization (control) strategies, including pollution prevention measures as appropriate, to maintain the effluent concentration at or below the water quality-based effluent limitation. Pollution prevention measures may be particularly appropriate for persistent bioaccumulative priority pollutants where there is evidence that beneficial uses are being impacted. The Central Coast Water Board may consider cost effectiveness when establishing the requirements of a PMP. The completion and implementation of a Pollution Prevention Plan, if required pursuant to Water Code section 13263.3(d), shall be considered to fulfill the PMP requirements. Pollution Prevention Pollution Prevention means any action that causes a net reduction in the use or generation of a hazardous substance or other pollutant that is discharged into water and includes, but is not limited to, input change, operational improvement, production process change, and product reformulation (as defined in Water Code section 13263.3). Pollution prevention does not include actions that merely shift a pollutant in wastewater from one environmental medium to another environmental medium, unless clear environmental benefits of such an approach are identified to the satisfaction of the State Water Board or Central Coast Water Board. Reporting Level (RL) The RL is the ML (and it s associated analytical method) chosen by the Discharger for reporting and compliance determination from the MLs included in this Order, including an additional factor if CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT A – DEFINITIONS A-4 applicable as discussed herein. The MLs included in this Order correspond to approved analytical methods for reporting a sample result that are selected by the Central Coast Water Board either from Appendix 4 of the SIP in accordance with section 2.4.2 of the SIP or established in accordance with section 2.4.3 of the SIP. The ML is based on the proper application of method-based analytical procedures for sample preparation and the absence of any matrix interferences. Other factors may be applied to the ML depending on the specific sample preparation steps employed. For example, the treatment typically applied in cases where there are matrix-effects is to dilute the sample or sample aliquot by a factor of ten. In such cases, this additional factor must be applied to the ML in the computation of the RL. Source of Drinking Water Any water designated as municipal or domestic supply (MUN) in the Central Coast Water Board Basin Plan. Standard Deviation (σ) Standard Deviation is a measure of variability that is calculated as follows: σ = (∑[(x - µ)2]/(n – 1))0.5 where: x is the observed value; µ is the arithmetic mean of the observed values; and n is the number of samples. Toxicity Reduction Evaluation (TRE) TRE is a study conducted in a step-wise process designed to identify the causative agents of effluent or ambient toxicity, isolate the sources of toxicity, evaluate the effectiveness of toxicity control options, and then confirm the reduction in toxicity. The first steps of the TRE consist of the collection of data relevant to the toxicity, including additional toxicity testing, and an evaluation of facility operations and maintenance practices, and best management practices. A Toxicity Identification Evaluation (TIE) may be required as part of the TRE, if appropriate. (A TIE is a set of procedures to identify the specific chemical(s) responsible for toxicity. These procedures are performed in three phases (characterization, identification, and confirmation) using aquatic organism toxicity tests.) CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT B –MAP B-1 B. ATTACHMENT B – MAP Drawing Reference: SAN LUIS OBISPO (CA) U.S.G.S TOPOGRAPHIC MAP 7.5 MINUTE QUADRANGLE Date: 1981 SITE LOCATION MAP CITY OF SAN LUIS OBISPO WATER RECLAMATION FACILITY SAN LUIS OBISPO COUNTY Facility Location CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT C – WASTEWATER FLOW SCHEMATIC C-1 C. ATTACHMENT C – FLOW SCHEMATIC CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-1 D. ATTACHMENT D – STANDARD PROVISIONS I. FEDERAL STANDARD PROVISIONS – PERMIT COMPLIANCE A. Federal Standard Provisions – Permit Compliance 1. Duty to Comply a. The Discharger must comply with all of the conditions of this Order. Any noncompliance constitutes a violation of the Clean Water Act (CWA) and the California Water Code and is grounds for enforcement action, for permit termination, revocation and reissuance, or modification; or denial of a permit renewal application. (40 C.F.R. § 122.41(a).) b. The Discharger shall comply with effluent standards or prohibitions established under Section 307(a) of the CWA for toxic pollutants and with standards for sewage sludge use or disposal established under Section 405(d) of the CWA within the time provided in the regulations that establish these standards or prohibitions, even if this Order has not yet been modified to incorporate the requirement. (40 C.F.R. § 122.41(a)(1).) 2. Need to Halt or Reduce Activity Not a Defense. It shall not be a defense for a Discharger in an enforcement action that it would have been necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this Order. [40 C.F.R. § 122.41(c)]. 3. Duty to Mitigate. The Discharger shall take all reasonable steps to minimize or prevent any discharge or sludge use or disposal in violation of this Order that has a reasonable likelihood of adversely affecting human health or the environment. [40 C.F.R. § 122.41(d)]. 4. Proper Operation and Maintenance. The Discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the Discharger to achieve compliance with the conditions of this Order. Proper operation and maintenance also includes adequate laboratory controls and appropriate quality assurance procedures. This provision requires the operation of backup or auxiliary facilities or similar systems that are installed by a Discharger only when necessary to achieve compliance with the conditions of this Order [40 C.F.R. § 122.41(e)]. 5. Property Rights a. This Order does not convey any property rights of any sort or any exclusive privileges [40 C.F.R. § 122.41(g)]. b. The issuance of this Order does not authorize any injury to persons or property or invasion of other private rights, or any infringement of state or local law or regulations [40 C.F.R. § 122.5(c)]. 6. Inspection and Entry. The Discharger shall allow the Central Coast Water Board, State Water Board, United States Environmental Protection Agency (USEPA), and/or their authorized representatives (including an authorized contractor acting as their representative), upon the presentation of credentials and other documents, as may be required by law, to [40 C.F.R. § 122.41(i); Water Code §13383]: CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-2 a. Enter upon the Discharger's premises where a regulated facility or activity is located or conducted, or where records are kept under the conditions of this Order [40 C.F.R. § 122.41(i)(1)]; b. Have access to and copy, at reasonable times, any records that must be kept under the conditions of this Order [40 C.F.R. § 122.41(i)(2)]; c. Inspect and photograph, at reasonable times, any facilities, equipment (including monitoring and control equipment), practices, or operations regulated or required under this Order [40 C.F.R. § 122.41(i)(3)]; and d. Sample or monitor, at reasonable times, for the purposes of assuring Order compliance or as otherwise authorized by the CWA or the Water Code, any substances or parameters at any location [40 C.F.R. § 122.41(i)(4)]. 7. Bypass a. Definitions i. “Bypass” means the intentional diversion of waste streams from any portion of a treatment facility [40 C.F.R. § 122.41(m)(1)(i)]. ii. “Severe property damage” means substantial physical damage to property, damage to the treatment facilities, which causes them to become inoperable, or substantial and permanent loss of natural resources that can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production [40 C.F.R. § 122.41(m)(1)(ii)]. b. Bypass not exceeding limitations. The Discharger may allow any bypass to occur which does not cause exceedances of effluent limitations, but only if it is for essential maintenance to assure efficient operation. These bypasses are not subject to the provisions listed in Federal Standard Provisions – Permit Compliance I.A.7.c, I.A.7.d, and I.A.7.e below [40 C.F.R. § 122.41(m)(2)]. c. Prohibition of bypass. Bypass is prohibited, and the Central Coast Water Board may take enforcement action against a Discharger for bypass, unless [40 C.F.R. § 122.41(m)(4)(i)]: i. Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage [40 C.F.R. § 122.41(m)(4)(i)(A)]; ii. There were no feasible alternatives to the bypass, such as use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back-up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass that occurred during normal periods of equipment downtime or preventive maintenance [40 C.F.R. § 122.41(m)(4)(i)(B)]; and iii. The Discharger submitted notice to the Central Coast Water Board as required under Federal Standard Provisions – Permit Compliance I.A.7.e below [40 C.F.R. § 122.41(m)(4)(i)(C)]. d. The Central Coast Water Board may approve an anticipated bypass, after considering its adverse effects, if the Central Coast Water Board determines that it will meet the three conditions listed in Federal Standard Provisions – Permit Compliance I.A.7.c above [40 C.F.R. § 122.41(m)(4)(ii)]. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-3 e. Notice. i. Anticipated bypass. If the Discharger knows in advance of the need for a bypass, it shall submit a notice, if possible at least 10 days before the date of the bypass [40 C.F.R. § 122.41(m)(3)(i)]. ii. Unanticipated bypass. The Discharger shall submit notice of an unanticipated bypass as required in Federal Standard Provisions - Reporting I.E.5 below (24- hour notice) [40 C.F.R. § 122.41(m)(3)(ii)]. 8. Upset. Upset means an exceptional incident in which there is unintentional and temporary noncompliance with technology based permit effluent limitations because of factors beyond the reasonable control of the Discharger. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation [40 C.F.R. § 122.41(n)(1)]. a. Effect of an upset. An upset constitutes an affirmative defense to an action brought for noncompliance with such technology based permit effluent limitations if the requirements of Federal Standard Provisions – Permit Compliance I.A.8.b below are met. No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review [40 C.F.R. § 122.41(n)(2)]. b. Conditions necessary for a demonstration of upset. A Discharger who wishes to establish the affirmative defense of upset shall demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that [40 C.F.R. § 122.41(n)(3)]: c. Burden of proof. In any enforcement proceeding, the Discharger seeking to establish the occurrence of an upset has the burden of proof [40 C.F.R. § 122.41(n)(4)]. B. Federal Standard Provisions – Permit Action 1. General. This Order may be modified, revoked and reissued, or terminated for cause. The filing of a request by the Discharger for modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not stay any Order condition [40 C.F.R. § 122.41(f)]. 2. Duty to Reapply. If the Discharger wishes to continue an activity regulated by this Order after the expiration date of this Order, the Discharger must apply for and obtain a new permit [40 C.F.R. § 122.41(b)]. 3. Transfers. This Order is not transferable to any person except after notice to the Central Coast Water Board. The Central Coast Water Board may require modification or revocation and reissuance of the Order to change the name of the Discharger and incorporate such other requirements as may be necessary under the CWA and the Water Code [40 C.F.R. § 122.41(l)(3); §122.61]. C. Federal Standard Provisions – Monitoring 1. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity [40 C.F.R. § 122.41(j)(1)]. 2. Monitoring results must be conducted according to test procedures under 40 C.F.R. part 136 or, in the case of sludge use or disposal, approved under 40 C.F.R. part 136 unless otherwise specified in 40 C.F.R. part 503 unless other test procedures have been specified in this Order [40 C.F.R. § 122.41(j)(4); § 122.44(i)(1)(iv)]. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-4 D. Federal Standard Provisions – Records 1. Records Retention. Except for records of monitoring information required by this Order related to the Discharger's sewage sludge use and disposal activities, which shall be retained for a period of at least five years (or longer as required by 40 C.F.R. part 503), the Discharger shall retain records of all monitoring information, including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation, copies of all reports required by this Order, and records of all data used to complete the application for this Order, for a period of at least three (3) years from the date of the sample, measurement, report or application. This period may be extended by request of the Central Coast Water Board Executive Officer at any time. (40 C.F.R. § 122.41(j)(2).) 2. Records of monitoring information shall include: a. The date, exact place, and time of sampling or measurements [40 C.F.R. § 122.41(j)(3)(i)]; b. The individual(s) who performed the sampling or measurements [40 C.F.R. § 122.41(j)(3)(ii)]; c. The date(s) analyses were performed [40 CF.R. § 122.41(j)(3)(iii)]; d. The individual(s) who performed the analyses [40 C.F.R. § 122.41(j)(3)(iv)]; e. The analytical techniques or methods used [40 C.F.R. § 122.41(j)(3)(v)]; and f. The results of such analyses [40 C.F.R. § 122.41(j)(3)(vi)]. 3. Claims of confidentiality for the following information will be denied [40 C.F.R. § 122.7(b)]: a. The name and address of any permit applicant or Discharger [40 C.F.R. § 122.7(b)(1)]; and b. Permit applications and attachments, permits and effluent data [40 C.F.R. § 122.7(b)(2)]. E. Federal Standard Provisions – Reporting 1. Duty to Provide Information. The Discharger shall furnish to the Central Coast Water Board, State Water Board, or USEPA within a reasonable time, any information which the Central Coast Water Board, State Water Board, or USEPA may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this Order or to determine compliance with this Order. Upon request, the Discharger shall also furnish to the Central Coast Water Board, State Water Board, or USEPA copies of records required to be kept by this Order [40 C.F.R. § 122.41(h); Water Code §13267]. 2. Signatory and Certification Requirements a. All applications, reports, or information submitted to the Central Coast Water Board, State Water Board, and/or USEPA shall be signed and certified in accordance with Federal Standard Provisions – Reporting I.E.2.b, I.E.2.c, I.E.2.d and I.E.2.e below [40 C.F.R. § 122.41(k)]. b. All permit applications shall be signed by a responsible corporate officer. For the purpose of this section, a responsible corporate officer means: (i) A president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy- or decision- making functions for the corporation, or (ii) the manager of one or more CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-5 manufacturing, production, or operating facilities, provided, the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmental compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures [40 C.F.R. § 122.22(a)(1)]. c. All reports required by this Order and other information requested by the Central Coast Water Board, State Water Board, or USEPA shall be signed by a person described in Federal Standard Provisions – Reporting I.E.2.b above, or by a duly authorized representative of that person. A person is a duly authorized representative only if: i. The authorization is made in writing by a person described in Federal Standard Provisions – Reporting I.E.2.b above [40 C.F.R. § 122.22(b)(1)]; ii. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the company. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.) [40 C.F.R. § 122.22(b)(2)]; and iii. The written authorization is submitted to the Central Coast Water Board and State Water Board [40 C.F.R. § 122.22(b)(3)]. d. If an authorization under Federal Standard Provisions – Reporting I.E.2.c above is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of Standard Provisions – Reporting V.B.3 above must be submitted to the Central Coast Water Board and State Water Board prior to or together with any reports, information, or applications, to be signed by an authorized representative [40 C.F.R. § 122.22(c)]. e. Any person signing a document under Federal Standard Provisions – Reporting I.E.2.b or I.E.2.c above shall make the following certification: “I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.” [40 C.F.R. § 122.22(d)]. 3. Monitoring Reports a. Monitoring results shall be reported at the intervals specified in the Monitoring and Reporting Program (Attachment E) in this Order [40 C.F.R. § 122.41(l)(4)]. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-6 b. Monitoring results must be reported on a Discharge Monitoring Report (DMR) form or forms provided or specified by the Central Coast Water Board or State Water Board for reporting results of monitoring of sludge use or disposal practices [40 C.F.R. § 122.41(l)(4)(i)]. c. If the Discharger monitors any pollutant more frequently than required by this Order using test procedures approved under 40 C.F.R. part 136 or, in the case of sludge use or disposal, approved under 40 C.F.R. part 136 unless otherwise specified in 40 C.F.R. part 503, or as specified in this Order, the results of this monitoring shall be included in the calculation and reporting of the data submitted in the DMR or sludge reporting form specified by the Central Coast Water Board [40 C.F.R. § 122.41(l)(4)(ii)]. d. Calculations for all limitations, which require averaging of measurements, shall utilize an arithmetic mean unless otherwise specified in this Order [40 C.F.R. § 122.41(l)(4)(iii)]. 4. Compliance Schedules. Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule of this Order, shall be submitted no later than 14 days following each schedule date [40 C.F.R. § 122.41(l)(5)]. 5. Twenty-Four Hour Reporting a. The Discharger shall report any noncompliance that may endanger health or the environment. Any information shall be provided orally within 24 hours from the time the Discharger becomes aware of the circumstances. A written submission shall also be provided within five (5) days of the time the Discharger becomes aware of the circumstances. The written submission shall contain a description of the noncompliance and its cause; the period of noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance [40 C.F.R. § 122.41(l)(6)(i)]. b. The following shall be included as information that must be reported within 24 hours under this paragraph [40 C.F.R. § 122.41(l)(6)(ii)]: i. Any unanticipated bypass that exceeds any effluent limitation in this Order [40 C.F.R. § 122.41(l)(6)(ii)(A)]. ii. Any upset that exceeds any effluent limitation in this Order [40 C.F.R. § 122.41(l)(6)(ii)(B)]. c. The Central Coast Water Board may waive the above-required written report under this provision on a case-by-case basis if an oral report has been received within 24 hours [40 C.F.R. § 122.41(l)(6)(iii)]. 6. Planned Changes. The Discharger shall give notice to the Central Coast Water Board as soon as possible of any planned physical alterations or additions to the permitted facility. Notice is required under this provision only when [40 C.F.R. § 122.41(l)(1)]. a. The alteration or addition to a permitted facility may meet one of the criteria for determining whether a facility is a new source in § 122.29(b) [40 C.F.R. § 122.41(l)(1)(i)]; or b. The alteration or addition could significantly change the nature or increase the quantity of pollutants discharged. This notification applies to pollutants that are not subject to effluent limitations in this Order [40 C.F.R. § 122.41(l)(1)(ii)]. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-7 c. The alteration or addition results in a significant change in the Discharger's sludge use or disposal practices, and such alteration, addition, or change may justify the application of permit conditions that are different from or absent in the existing permit, including notification of additional use or disposal sites not reported during the permit application process or not reported pursuant to an approved land application plan [40 C.F.R. § 122.41(l)(1)(iii)]. 7. Anticipated Noncompliance. The Discharger shall give advance notice to the Central Coast Water Board or State Water Board of any planned changes in the permitted facility or activity that may result in noncompliance with General Order requirements. [40 C.F.R. § 122.41(l)(2)]. 8. Other Noncompliance. The Discharger shall report all instances of noncompliance not reported under Federal Standard Provisions – Reporting I.E.3, I.E.4, and I.E.5 above at the time monitoring reports are submitted. The reports shall contain the information listed in Federal Standard Provisions – Reporting I.E.5 above. [40 C.F.R. § 122.41(l)(7)]. 9. Other Information. When the Discharger becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or in any report to the Central Coast Water Board, State Water Board, or USEPA, the Discharger shall promptly submit such facts or information [40 C.F.R. § 122.41(l)(8)]. F. Federal Standard Provisions – Enforcement 1. The Central Coast Water Board is authorized to enforce the terms of this permit under several provisions of the Water Code, including, but not limited to, §§13385, 13386, and 13387. G. Additional Federal Provisions – Notification Levels 1. Non-Municipal Facilities. Existing manufacturing, commercial, mining, and silvicultural Dischargers shall notify the Central Coast Water Board as soon as they know or have reason to believe [40 C.F.R. § 122.42(a)]: a. That any activity has occurred or will occur that would result in the discharge, on a routine or frequent basis, of any toxic pollutant that is not limited in this Order, if that discharge will exceed the highest of the following "notification levels" [40 C.F.R. § 122.42(a)(1)]: i. 100 micrograms per liter (μg/L) [40 C.F.R. § 122.42(a)(1)(i)]; ii. 200 μg/L for acrolein and acrylonitrile; 500 μg/L for 2,4-dinitrophenol and 2-methyl-4, 6-dinitrophenol; and 1 milligram per liter (mg/L) for antimony [40 C.F.R. § 122.42(a)(1)(ii)]; iii. Five (5) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge [40 C.F.R. § 122.42(a)(1)(iii)]; or iv. The level established by the Central Coast Water Board in accordance with 40 C.F.R. § 122.44(f) [40 C.F.R. § 122.42(a)(1)(iv)]. b. That any activity has occurred or will occur that would result in the discharge, on a non-routine or infrequent basis, of any toxic pollutant that is not limited in this Order, if that discharge will exceed the highest of the following “notification levels" [40 C.F.R. § 122.42(a)(2)]: i. 500 micrograms per liter (μg/L) [40 C.F.R. § 122.42(a)(2)(i)]; ii. 1 milligram per liter (mg/L) for antimony [40 C.F.R. § 122.42(a)(2)(ii)]; CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-8 iii. Ten (10) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge [40 C.F.R. § 122.42(a)(2)(iii)]; or iv. The level established by the Central Coast Water Board in accordance with 40 C.F.R. § 122.44(f) [40 C.F.R. § 122.42(a)(2)(iv)]. 2. Publicly Owned Treatment Works (POTWs). All POTWs shall provide adequate notice to the Central Coast Water Board of the following [40 C.F.R. § 122.42(b)]: a. Any new introduction of pollutants into the POTW from an indirect discharger that would be subject to sections 301 or 306 of the CWA if it were directly discharging those pollutants [40 C.F.R. § 122.42(b)(1)]; and b. Any substantial change in the volume or character of pollutants being introduced into that POTW by a source introducing pollutants into the POTW at the time of adoption of the Order. [40 C.F.R. § 122.42(b)(2)] c. Adequate notice shall include information on the quality and quantity of effluent introduced into the POTW as well as any anticipated impact of the change on the quantity or quality of effluent to be discharged from the POTW. [40 C.F.R. § 122.42(b)(3)] CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-9 II. CENTRAL COAST REGION’S STANDARD PROVISIONS (JANUARY 2013) A. Central Coast General Permit Conditions 1. Introduction of "incompatible wastes" to the treatment system is prohibited. 2. Discharge of high-level radiological waste and of radiological, chemical, and biological warfare agents is prohibited. 3. Discharge of "toxic pollutants" in violation of effluent standards and prohibitions established under Section 307(a) of the Clean Water Act is prohibited. 4. Discharge of sludge, sludge digester or thickener supernatant, and sludge drying bed leachate to drainageways, surface waters, or the ocean is prohibited. 5. Introduction of pollutants into the collection, treatment, or disposal system by an "indirect discharger” that: a. Inhibit or disrupt the treatment process, system operation, or the eventual use or disposal of sludge; or, b. Flow through the system to the receiving water untreated; and, c. Cause or "significantly contribute" to a violation of any requirement of this Order, is prohibited. 6. Introduction of "pollutant free" wastewater to the collection, treatment, and disposal system in amounts that threaten compliance with this order is prohibited. B. Central Coast Standard Provisions – Provisions 1. Collection, treatment, and discharge of waste shall not create a nuisance or pollution, as defined by Section 13050 of the California Water Code. 2. All facilities used for transport or treatment of wastes shall be adequately protected from inundation and washout as the result of a 100-year frequency flood. 3. Operation of collection, treatment, and disposal systems shall be in a manner that precludes public contact with wastewater. 4. Collected screenings, sludges, and other solids removed from liquid wastes shall be disposed in a manner approved by the Executive Officer. 5. Wastewater treatment plants shall be supervised and operated by persons possessing certificates of appropriate grade pursuant to Title 23 of the California Code of Regulations. 6. After notice and opportunity for a hearing, this order may be terminated for cause, including, but not limited to: a. violation of any term or condition contained in this order; b. obtaining this order by misrepresentation, or by failure to disclose fully all relevant facts; c. a change in any condition or endangerment to human health or environment that requires a temporary or permanent reduction or elimination of the authorized discharge; and, d. a substantial change in character, location, or volume of the discharge. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-10 7. Provisions of this permit are severable. If any provision of the permit is found invalid, the remainder of the permit shall not be affected. 8. After notice and opportunity for hearing, this order may be modified or revoked and reissued for cause, including: a. Promulgation of a new or revised effluent standard or limitation; b. A material change in character, location, or volume of the discharge; c. Access to new information that affects the terms of the permit, including applicable schedules; d. Correction of technical mistakes or mistaken interpretations of law; and e. Other causes set forth under Subpart D of 40 C.F.R. 122. 9. Safeguards shall be provided to assure maximal compliance with all terms and conditions of this permit. Safeguards shall include preventative and contingency plans and may also include alternative power sources, stand-by generators, retention capacity, operating procedures, or other precautions. Preventative and contingency plans for controlling and minimizing the effect of accidental discharges shall: a. Identify possible situations that could cause "upset", "overflow" or "bypass”, or other noncompliance. (Loading and storage areas, power outage, waste treatment unit outage, and failure of process equipment, tanks and pipes should be considered.) b. Evaluate the effectiveness of present facilities and procedures and describe procedures and steps to minimize or correct any adverse environmental impact resulting from noncompliance with the permit. 10. Physical Facilities shall be designed and constructed according to accepted engineering practice and shall be capable of full compliance with this order when properly operated and maintained. Proper operation and maintenance shall be described in an Operation and Maintenance Manual. Facilities shall be accessible during the wet-weather season. 11. The discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) that are installed or used by the discharger to achieve compliance with the conditions of this order. Electrical and mechanical equipment shall be maintained in accordance with appropriate practices and standards, such as NFPA 70B, Recommended Practice for Electrical Equipment Maintenance; NFPA 70E, Standard for Electrical Safety in the Workplace; ANSI/NETA MTS Standard for Maintenance: Testing Specifications for Electrical Power Equipment and Systems, or procedures established by insurance companies or other industry resources. 12. If the discharger’s facilities are equipped with SCADA or other systems that implement wireless, remote operation, the discharger should implement appropriate safeguards against unauthorized access to the wireless systems. Standards such as NIST SP 800- 53, Recommended Security Controls for Federal Information Systems, can provide guidance. 13. Production and use of recycled water is subject to the approval of the Board. Production and use of recycled water shall be in conformance with reclamation criteria established in Chapter 3, Title 22, of the California Code of Regulations and Chapter 7, Division 7, of the California Water Code. An engineering report pursuant to section 60323, Title 22, of the California Code of Regulations is required and a waiver or water reclamation requirements from the Board is required before reclaimed water is supplied for any use, CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-11 or to any user, not specifically identified and approved either in this Order or another order issued by this Board. C. Central Coast Standard Provisions – General Monitoring Requirements 1. If results of monitoring a pollutant appear to violate effluent limitations based on a weekly, monthly, 30-day, or six-month period, but compliance or non-compliance cannot be validated because sampling is too infrequent, the frequency of sampling shall be increased to validate the test within the next monitoring period. The increased frequency shall be maintained until the Executive Officer agrees the original monitoring frequency may be resumed. For example, if copper is monitored annually and results exceed the six-month median numerical effluent limitation in the permit, monitoring of copper must be increased to a frequency of at least once every two months (Central Coast Standard Provisions – Definitions II.F.13.). If suspended solids are monitored weekly and results exceed the weekly average numerical limit in the permit, monitoring of suspended solids must be increased to at least four (4) samples every week (Central Coast Standard Provisions – Definitions II.F.14.). 2. Water quality analyses performed in order to monitor compliance with this permit shall be by a laboratory certified by the State Department of Public Health (DPH) for the constituent(s) being analyzed. Bioassay(s) performed in order to monitor compliance with this permit shall be in accord with guidelines approved by the State Water Resources Control Board and the State Department of Fish and Game. 3. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. Samples shall be taken during periods of peak loading conditions. Influent samples shall be samples collected from the combined flows of all incoming wastes, excluding recycled wastes. Effluent samples shall be samples collected downstream of the last treatment unit and tributary flow and upstream of any mixing with receiving waters. 4. All monitoring instruments and devices used by the discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. D. Central Coast Standard Provisions – General Reporting Requirements 1. Reports of marine monitoring surveys conducted to meet receiving water monitoring requirements of the Monitoring and Reporting Program shall include at least the following information: a. A description of climatic and receiving water characteristics at the time of sampling (weather observations, floating debris, discoloration, wind speed and direction, swell or wave action, time of sampling, tide height, etc.). b. A description of sampling stations, including differences unique to each station (e.g., station location, grain size, rocks, shell litter, calcareous worm tubes, evident life, etc.). c. A description of the sampling procedures and preservation sequence used in the survey. d. A description of the exact method used for laboratory analysis. In general, analysis shall be conducted according to (Central Coast Standard Provisions – Definitions II.B.1 above, and Federal Standard Provision – Monitoring I.C.1. However, CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-12 variations in procedure are acceptable to accommodate the special requirements of sediment analysis. All such variations must be reported with the test results. e. A brief discussion of the results of the survey. The discussion shall compare data from the control station with data from the outfall stations. All tabulations and computations shall be explained. 2. Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule shall be submitted within 14 days following each scheduled date unless otherwise specified within the permit. If reporting noncompliance, the report shall include a description of the reason, a description and schedule of tasks necessary to achieve compliance, and an estimated date for achieving full compliance. A second report shall be submitted within 14 days of full compliance. 3. The “Discharger” shall file a report of waste discharge at least 180 days before making any material change or proposed change in the character, location, or plume of the discharge. 4. Within 120 days after the discharger discovers, or is notified by the Central Coast Water Board, that monthly average daily flow will or may reach design capacity of waste treatment and/or disposal facilities within four (4) years, the discharger shall file a written report with the Central Coast Water Board. The report shall include: a. the best estimate of when the monthly average daily dry weather flow rate will equal or exceed design capacity; and, b. a schedule for studies, design, and other steps needed to provide additional capacity for waste treatment and/or disposal facilities before the waste flow rate equals the capacity of present units. In addition to complying with Federal Standard Provision – Reporting I.E.2, the required technical report shall be prepared with public participation and reviewed, approved and jointly submitted by all planning and building departments having jurisdiction in the area served by the waste collection, treatment, or disposal facilities. 5. All “Dischargers” shall submit reports electronically to the: California Regional Water Quality Control Board Central Coast Region centralcoast@waterboards.ca.gov 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 In addition, "Dischargers" with designated major discharges shall submit a copy of each document to: Regional Administrator USEPA, Region 9 Attention: CWA Standards and Permits Office (WTR-5) 75 Hawthorne Street San Francisco, California 94105 6. Transfer of control or ownership of a waste discharge facility must be preceded by a notice to the Central Coast Water Board at least 30 days in advance of the proposed transfer date. The notice must include a written agreement between the existing CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-13 “Discharger” and proposed “Discharger” containing specific date for transfer of responsibility, coverage, and liability between them. Whether a permit may be transferred without modification or revocation and reissuance is at the discretion of the Board. If permit modification or revocation and reissuance are necessary, transfer may be delayed 180 days after the Central Coast Water Board's receipt of a complete permit application. Please also see Federal Standard Provision – Permit Action IB.3. 7. Except for data determined to be confidential under Section 308 of the Clean Water Act (excludes effluent data and permit applications), all reports prepared in accordance with this permit shall be available for public inspection at the office of the Central Coast Water Board or Regional Administrator of EPA. Please also see Federal Standard Provision – Records I.D.3. 8. By February 1st of each year, the discharger shall submit an annual report to the Central Coast Water Board. The report shall contain the following: a. Both tabular and graphical summaries of the monitoring data obtained during the previous year. b. A discussion of the previous year’s compliance record and corrective actions taken, or which may be needed, to bring the discharger into full compliance. c. An evaluation of wastewater flows with projected flow rate increases over time and the estimated date when flows will reach facility capacity. d. A discussion of operator certification and a list of current operating personnel and their grades of certification. e. The date of the facility’s Operation and Maintenance Manual (including contingency plans as described in Provision B.9), the date the manual was last reviewed, and whether the manual is complete and valid for the current facility. f. A discussion of the laboratories used by the discharger to monitor compliance with effluent limits and a summary of performance relative to Section C, General Monitoring Requirements. g. If the facility treats industrial or domestic wastewater and there is no provision for periodic sludge monitoring in the Monitoring and Reporting Program, the report shall include a summary of sludge quantities, analyses of its chemical and moisture content, and its ultimate destination. h. If appropriate, the report shall also evaluate the effectiveness of the local source control or pretreatment program using the State Water Resources Control Board's "Guidelines for Determining the Effectiveness of Local Pretreatment Program." E. Central Coast Standard Provisions – General Pretreatment Provisions 1. Discharge of pollutants by "indirect dischargers” in specific industrial sub-categories (appendix C, 40 C.F.R. part 403), where categorical pretreatment standards have been established, or are to be established, (according to 40 C.F.R. Chapter 1, Subchapter N), shall comply with the appropriate pretreatment standards by the date specified therein or, if a new indirect discharger, upon commencement of discharge. F. Central Coast Standard Provisions – Enforcement CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-14 1. Any person failing to file a report of waste discharge or other report as required by this permit shall be subject to a civil penalty not to exceed $5,000 per day. 2. Upon reduction, loss, or failure of the treatment facility, the "Discharger" shall, to the extent necessary to maintain compliance with this permit, control production or all discharges, or both, until the facility is restored or an alternative method of treatment is provided. G. Central Coast Standard Provisions – Definitions (Not otherwise included in Attachment A to this Order) 1. A “composite sample" is a combination of no fewer than eight (8) individual samples obtained at equal time intervals (usually hourly) over the specified sampling (composite) period. The volume of each individual sample is proportional to the flow rate at the time of sampling. The period shall be specified in the Monitoring and Reporting Program ordered by the Executive Officer. 2. “Daily Maximum” limit means the maximum acceptable concentration or mass emission rate of a pollutant measured during a calendar day or during any 24-hour period reasonably representative of the calendar day for purposes of sampling. It is normally compared with results based on "composite samples” except for ammonia, total chlorine, phenolic compounds, and toxicity concentration. For all exceptions, comparisons will be made with results from a “grab sample”. 3. “Discharger", as used herein, means, as appropriate: (l) the Discharger, (2) the local sewering entity (when the collection system is not owned and operated by the Discharger), or (3) "indirect discharger" (where "Discharger" appears in the same paragraph as "indirect discharger”, it refers to the discharger.) 4. “Duly Authorized Representative" is one where: a. the authorization is made in writing by a person described in the signatory paragraph of Federal Standard Provision I.E.2; b. the authorization specifies either an individual or the occupant of a position having either responsibility for the overall operation of the regulated facility, such as the plant manager, or overall responsibility for environmental matters of the company; and, c. the written authorization was submitted to the Central Coast Water Board. 5. A "grab sample" is defined as any individual sample collected in less than 15 minutes. "Grab samples” shall be collected during peak loading conditions, which may or may not be during hydraulic peaks. It is used primarily in determining compliance with the daily maximum limits identified in Central Coast Standard Provision – Provision II.F.2 and instantaneous maximum limits. 6. "Hazardous substance” means any substance designated under 40 C.F.R. 116 pursuant to Section 311 of the Clean Water Act. 7. "Incompatible wastes” are: a. Wastes which create a fire or explosion hazard in the treatment works; b. Wastes which will cause corrosive structural damage to treatment works, or wastes with a pH lower than 5.0 unless the works is specifically designed to accommodate such wastes; CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-15 c. Solid or viscous wastes in amounts which cause obstruction to flow in sewers, or which cause other interference with proper operation of treatment works; d. Any waste, including oxygen demanding pollutants (BOD, etc), released in such volume or strength as to cause inhibition or disruption in the treatment works and subsequent treatment process upset and loss of treatment efficiency; and, e. Heat in amounts that inhibit or disrupt biological activity in the treatment works or that raise influent temperatures above 40°C (104°F) unless the treatment works is designed to accommodate such heat. 8. "Indirect Discharger” means a non-domestic discharger introducing pollutants into a publicly owned treatment and disposal system. 9. "Log Mean” is the geometric mean. Used for determining compliance of fecal or total coliform populations, it is calculated with the following equation: Log Mean = (C1 x C2 x...x Cn)1/n in which “n" is the number of days samples were analyzed during the period and any "C" is the concentration of bacteria (MPN/100 ml) found on each day of sampling. "n” should be five or more. 10. “Mass emission rate" is a daily rate defined by the following equations: mass emission rate (lbs/day) = 8.34 x Q x C; and, mass emission rate (kg/day) = 3.79 x Q x C, where “C" (in mg/l) is the measured daily constituent concentration or the average of measured daily constituent concentrations and “Q” (in MGD) is the measured daily flow rate or the average of measured daily flow rates over the period of interest. 11. The "Maximum Allowable Mass Emission Rate," whether for a month, week, day, or six- month period, is a daily rate determined with the formulas in paragraph F.10, above, using the effluent concentration limit specified in the permit for the period and the average of measured daily flows (up to the allowable flow) over the period. 12. “Maximum Allowable Six-Month Median Mass Emission Rate" is a daily rate determined with the formulas in Central Coast Standard Provision – Provision II.F.10, above, using the "six-month Median" effluent limit specified in the permit, and the average of measured daily flows (up to the allowable flow) over a 180-day period. 13. "Median" is the value below which half the samples (ranked progressively by increasing value) fall. It may be considered the middle value, or the average of two middle values. 14. "Monthly Average" (or "Weekly Average”, as the case may be) is the arithmetic mean of daily concentrations or of daily mass emission rates over the specified 30-day (or 7-day) period Average = (Xl + X2 + ... + Xn) / n in which “n" is the number of days samples were analyzed during the period and “X" is either the constituent concentration (mg/l) or mass emission rate (kg/day or lbs/day) for each sampled day. “n" should be four or greater. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT D – STANDARD PROVISIONS D-16 15. "Municipality" means a city, town, borough, county, district, association, or other public body created by or under state law and having jurisdiction over disposal of sewage, industrial waste, or other waste. 16. "Overflow" means the intentional or unintentional diversion of flow from the collection and transport systems, including pumping facilities. 17. "Pollutant-free wastewater" means inflow and infiltration, storm waters, and cooling waters and condensates which are essentially free of pollutants. 18. "Primary Industry Category" means any industry category listed in 40 C.F.R. 122, Appendix A. 19. "Removal Efficiency" is the ratio of pollutants removed by the treatment unit to pollutants entering the treatment unit. Removal efficiencies of a treatment plant shall be determined using “Monthly averages" of pollutant concentrations (C, in mg/l) of influent and effluent samples collected about the same time and the following equation (or its equivalent): CEffluent Removal Efficiency (%) = l00 x (l – Ceffluent / Cinfluent) 20. "Severe property damage" means substantial physical damage to property, damage to treatment facilities which causes them to become inoperable, or substantial and permanent loss to natural resources which can reasonably be expected to occur in the absence of a "bypass”. It does not mean economic loss caused by delays in production. 21. "Sludge" means the solids, residues, and precipitates separated from, or created in, wastewater by the unit processes of a treatment system. 22. To "significantly contribute" to a permit violation means an "indirect discharger" must: a. Discharge a daily pollutant loading in excess of that allowed by contract with the "Discharger" or by Federal, State, or Local law; b. Discharge wastewater which substantially differs in nature or constituents from its average discharge; c. Discharge pollutants, either alone or in conjunction with discharges from other sources, which results in a permit violation or prevents sewage sludge use or disposal; or d. Discharge pollutants, either alone or in conjunction with pollutants from other sources that increase the magnitude or duration of permit violations. 23. "Toxic Pollutant" means any pollutant listed as toxic under Section 307 (a) (1) of the Clean Water Act or under 40 C.F.R. 122, Appendix D. Violation of maximum daily discharge limitations are subject to 24-hour reporting (Federal Standard Provisions I.E.5.). 24. “Zone of Initial Dilution" means the region surrounding or adjacent to the end of an outfall pipe or diffuser ports whose boundaries are defined through calculation of a plume model verified by the State Water Resources Control Board. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-1 E. ATTACHMENT E – MONITORING AND REPORTING PROGRAM Contents I. General Monitoring Provisions ................................................................................................... E-2 II. Monitoring Locations .................................................................................................................. E-3 III. Influent Monitoring Requirements ............................................................................................... E-4 A. Monitoring Location INF-001 ............................................................................................... E-4 IV. Effluent Monitoring Requirements .............................................................................................. E-4 A. Monitoring Location EFF-001 .............................................................................................. E-4 V. Whole Effluent Toxicity Testing Requirements ........................................................................... E-6 A. Whole Effluent Acute Toxicity – Monitoring Location EFF-001 ............................................ E-6 B. Whole Effluent Chronic Toxicity – Monitoring Location EFF-001 ......................................... E-6 C. Quality Assurance ............................................................................................................... E-8 D. Accelerated Monitoring Requirements ................................................................................ E-8 E. Conducting Toxicity Identification Evaluation (TIE) and Toxicity Reduction Evaluation (TRE) ........................................................................................................................................... E-8 VI. Land Discharge Monitoring Requirements – Not Applicable ....................................................... E-9 VII. Recycling Monitoring Requirements – Not Applicable ................................................................ E-9 VIII. Receiving Water Monitoring Requirements ................................................................................ E-9 A. Monitoring Location RSW -001, RSW-002, RSW -003, RSW-004, RSW-005, RSW-006, RSW - 007, RSW-008 .................................................................................................................... E-9 IX. Other Monitoring Requirements ............................................................................................... E-10 A. Solids/Biosolids Monitoring, Notification, and Reporting .................................................... E-10 B. Pretreatment Monitoring.................................................................................................... E-13 X. Reporting Requirements .......................................................................................................... E-16 A. General Monitoring and Reporting Requirements ............................................................. E-16 B. Self-Monitoring Reports (SMRs) ....................................................................................... E-16 C. Discharge Monitoring Reports (DMRs) .............................................................................. E-18 D. Other Reports ................................................................................................................... E-19 Tables Table E-1. Monitoring Station Locations........................................................................................... E-3 Table E-2. Influent Monitoring .......................................................................................................... E-4 Table E-3. Effluent Monitoring .......................................................................................................... E-4 Table E-4. Short-Term Methods for Estimating Chronic Toxicity – Fresh Water ............................... E-7 Table E-5. Receiving Water Monitoring Requirements ..................................................................... E-9 Table E-6. Monitoring Periods and Reporting Schedule ................................................................. E-17 CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-2 ATTACHMENT E – MONITORING AND REPORTING PROGRAM (MRP) The Code of Federal Regulations (40 C.F.R. § 122.48) requires that all NPDES permits specify monitoring and reporting requirements. Water Code sections 13267 and 13383 also authorize the Central Coast Water Board to require technical and monitoring reports. This MRP establishes monitoring and reporting requirements that implement federal and California regulations. I. GENERAL MONITORING PROVISIONS A. Laboratories analyzing monitoring samples shall be certified by the California Department of Public Health (DPH), in accordance with Water Code section 13176, and must include quality assurance/quality control data with their reports. B. Samples and measurements taken as required herein shall be representative of the volume and nature of the monitored discharge. All samples shall be taken at the monitoring locations specified below and, unless otherwise specified, before the monitored flow joins or is diluted by any other waste stream, body of water, or substance. Monitoring locations shall not be changed without notification to and approval of the Central Coast Water Board. C. Appropriate flow measurement devices and methods consistent with accepted scientific practices shall be selected and used to ensure the accuracy and reliability of measurements of the volume of monitored discharges. The devices shall be installed, calibrated, and maintained to ensure that the accuracy of the measurements is consistent with the accepted capability of that type of device. Devices selected shall be capable of measuring flows with a maximum deviation of less than ±10 percent from true discharge rates throughout the range of expected discharge volumes. Guidance in selection, installation, calibration, and operation of acceptable flow measurement devices can be obtained from the following references. 1. A Guide to Methods and Standards for the Measurement of Water Flow, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 421, May 1975, 96 pp. (Available from the U.S. Government Printing Office, Washington, D.C. 20402. Order by SD Catalog No. C13.10:421.) 2. Water Measurement Manual, U.S. Department of Interior, Bureau of Reclamation, Second Edition, Revised Reprint, 1974, 327 pp. (Available from the U.S. Government Printing Office, Washington D.C. 20402. Order by Catalog No. 172.19/2:W29/2, Stock No. S/N 24003- 0027.) 3. Flow Measurement in Open Channels and Closed Conduits, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 484, October 1977, 982 pp. (Available in paper copy or microfiche from National Technical Information Services (NTIS) Springfield, VA 22151. Order by NTIS No. PB-273 535/5ST.) 4. NPDES Compliance Sampling Manual, U.S. Environmental Protection Agency, Office of Water Enforcement, Publication MCD-51, 1977, 140 pp. (Available from the General Services Administration (8FFS), Centralized Mailing Lists Services, Building 41, Denver Federal Center, CO 80225.) D. All monitoring instruments and devices used by the Discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. All flow measurement devise shall be calibrated at least once per year to ensure continued accuracy of the devices. E. Monitoring results, including noncompliance, shall be reported at intervals and in a manner specified in this MRP. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-3 F. Unless otherwise specified by this MRP, all monitoring shall be conducted according to test procedures established at 40 C.F.R. 136, Guidelines Establishing Test Procedures for Analysis of Pollutants. All analyses shall be conducted using the lowest practical quantitation limit achievable using the specified methodology. Where effluent limitations are set below the lowest achievable quantitation limits, pollutants not detected at the lowest practical quantitation limits will be considered in compliance with effluent limitations. Analysis for toxics listed by the California Toxics Rule (CTR) shall also adhere to guidance and requirements contained in the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (2005) (SIP). II. MONITORING LOCATIONS The Discharger shall establish the following monitoring locations to demonstrate compliance with the effluent limitations, discharge specifications, and other requirements in this Order: Table E-1. Monitoring Station Locations Type of Sampling Location Monitoring Location Name Monitoring Location Description Influent INF-001 A location where a representative sample of the influent into the facility can be collected prior to any plant return flows or treatment processes Effluent EFF-001 A location where a representative sample of the effluent from the facility can be collected after all treatment processes and prior to commingling with other waste streams or being discharged into San Luis Obispo Creek Receiving Water RSW -001 At Fox Canyon Road Receiving Water RSW -002 At Mission Receiving Water RSW -003 At Marsh Street Bridge Receiving Water RSW -004 50 feet upstream of effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW -005 A location in San Luis Obispo Creek immediately upstream of the confluence with Prefumo Canyon Creek Receiving Water RSW -006 A location in Prefumo Canyon Creek 50 feet upstream of the confluence with San Luis Obispo Creek Receiving Water RSW -007 Approximately 0.5 miles downstream from effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW -008 At Higuera Street Bridge, near US 101 Biosolids BIO-001 Representative sample location for biosolids at the last point in the biosolids handling process (i.e., the drying beds just before removal). CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-4 III. INFLUENT MONITORING REQUIREMENTS A. Monitoring Location INF-001 1. The Discharger shall monitor influent to the facility at INF-001 as follows: Table E-2. Influent Monitoring Parameter Units Sample Type Minimum Sampling Frequency Biochemical Oxygen Demand, 5-day @ 20°C (BOD5) mg/L 24-hr. composite 1/Month Total Suspended Solids (TSS) mg/L 24-hr. composite 1/Month IV. EFFLUENT MONITORING REQUIREMENTS A. Monitoring Location EFF-001 1. The Discharger shall monitor effluent at EFF-001 as follows. Table E-3. Effluent Monitoring Parameter Units Sample Type Minimum Sampling Frequency Daily Flow MG Metered 1/Day Instantaneous Maximum Flow Rate MGD Metered 1/Day Maximum Daily Flow MGD Calculated 1/Month Mean Daily Flow MGD Calculated 1/Month BOD Mass Emissions Rate lbs/day Calculated 1/Month pH s.u. Grab 1/Day [1], [2] Chlorine Residual mg/L Continuous or Grab [1] Grab samples shall be taken a minimum of twice per day, and within 30 minutes of any excursion above 0.1 mg/L Total Chlorine lbs/day Instantaneous 1/Day Temperature °C Grab [2] 5/Week Fecal Coliform Organisms MPN/100 mL Grab 5/Week Total Coliform Organisms MPN/100 mL Grab 5/Week Settleable Solids ml/L 24-hr. composite 5/Week Ammonia (as N) mg/L Grab 1/Week Total Suspended Solids mg/L 24-hr. composite 1/Week Turbidity NTU 24-hr. composite 1/10 days BOD, 5-day mg/L Grab 1/Month Dissolved Oxygen mg/L Grab 1/Month Color mg/L Grab 1/Month Oil and Grease mg/L Grab 1/Month Total Kjeldahl Nitrogen (TKN) (as N) mg/L Grab 1/Month CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-5 Parameter Units Sample Type Minimum Sampling Frequency Chlorodibromomethane µg/L 24-hr. composite 1/Month Dichlorobromomethane µg/L 24-hr. composite 1/Month Nitrite (as N) mg/L Grab 1/Month Nitrate (as N) mg/L Grab 1/Month Dissolved Orthophosphate (as P) mg/L Grab 1/Month Total Phosphate (as P) mg/L Grab 1/Month Total Dissolved Solids mg/L Grab 1/Quarter Pentachlorophenol µg/L 24-hr. composite 1/Quarter N-Nitrosodimethylamine µg/L 24-hr. composite 1/Quarter Sodium mg/L Grab 1/Quarter Chloride mg/L Grab 1/Quarter Chronic Toxicity [3] TUc Grab 1/Year (in October) Acute Toxicity [3] TUa Grab 1/Year (in October) MBAS mg/L Grab 1/Year (in October) Boron mg/L Grab 1/Year (in October) Cobalt mg/L Grab 1/Year (in October) Iron mg/L Grab 1/Year (in October) Lithium mg/L Grab 1/Year (in October) Manganese mg/L Grab 1/Year (in October) Molybdenum mg/L Grab 1/Year (in October) Vanadium mg/L Grab 1/Year (in October) CTR Pollutants [4], [5] µg/L 24-hr. composite 1/Year (in October) Title 22 Pollutants [6], [7] µg/L 24-hr. composite 1/Year (in October) [1] Report minimum and maximum pH values and maximum chlorine residual value. Also report if there is natural flow in San Luis Obispo Creek. [2] Temperature and pH shall be measured simultaneously with the sample taken for measurement of total ammonia. Results shall be used to calculate un-ionized ammonia concentration. [3] Whole effluent acute and chronic toxicity monitoring shall be conducted according to the requirements established in section V of this Monitoring and Reporting Program. [4] The CTR Priority Pollutants are those listed by the California Toxics Rule at 40 C.F.R. § 131.38(b)(1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). The Discharger shall instruct its analytical laboratory to establish calibration standards so that the Minimum Levels (MLs) presented in Appendix 4 of the SIP are the lowest calibrate standards. The Discharger and its analytical laboratory shall select MLs, which are below applicable water quality criteria of the CTR; and when applicable water quality criteria are below all MLs, the Discharger and is analytical laboratory shall select the lowest ML. [5] Monitoring for the CTR pollutant in the effluent shall occur simultaneously with monitoring required for the CTR pollutants in the receiving water. [6] The Title 22 Pollutants are those for which primary Maximum Contaminant Levels (MCLs) have been established by the Department of Public Health and which are listed in Tables 64431-A and 64444-A of the California Code of Regulations, Title 22, Division 4, Chapter 15. Where these pollutants are included in other groups of pollutants (CTR Priority Pollutants), monitoring does not need to be duplicated. Analytical methods shall adhere to the Detection Limits for Purposes of Reporting (DLRs) established by Title 22 of the California Code of Regulations, Division 4, Chapter 15, section 64432 and 64445.1. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-6 [7] Monitoring for the Title 22 pollutants in the effluent shall occur simultaneously with monitoring required for the Title 22 pollutants in the receiving water. V. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS A. Whole Effluent Acute Toxicity – Monitoring Location EFF-001 1. Acute toxicity shall be evaluated by measuring survival of test organisms exposed to 96-hour static renewal toxicity tests. 2. Test organisms shall be fathead minnow unless the Executive Officer specifies in writing otherwise. The Discharger may be required by the Executive Officer to retest sensitivity upon changes to the facility or operations which may affect effluent toxicity. 3. All bioassays shall be performed using the most sensitive species based on the most recent screening test results and in accordance with the most up-to-date protocols in 40 C.F.R. part 136, currently in Methods for Measuring the Acute Toxicity of Effluents and Receiving Water to Freshwater and Marine Organisms, 5th Edition. 4. If the Discharger can demonstrate that specific identifiable substances in the discharge are rapidly rendered harmless upon discharge to the receiving water, compliance with the acute toxicity limitation may be determined after the test samples are adjusted to remove the influence of those substances. The Discharger must obtain written approval from the Executive Officer to authorize such an adjustment. 5. The sample shall be taken from treated effluent after disinfection. Monitoring of the bioassay water shall include, on a daily basis, the following parameters: pH, dissolved oxygen, ammonia (if toxicity is observed), temperature, hardness, and alkalinity. These results shall be reported in the monthly SMRs or as specified by the Central Coast Water Board. 6. The presence of acute toxicity shall be determined as significantly reduced survival of test organisms at 100 percent effluent compared to a control using a statistical t-test. The Discharger shall include with the SMR the percent survival of the organisms for both the effluent and control, and the results of the t-test (“statistically different” or “not statistically different”). If the control fish survival rate is less than 90 percent, the bioassay test shall be restarted with new fish and shall continue as soon as practical until an acceptable test is completed (i.e., control fish survival rate is 90 percent or greater). B. Whole Effluent Chronic Toxicity – Monitoring Location EFF-001 1. Chronic Toxicity Monitoring Requirements a. Toxicity Trigger. A toxicity trigger of 1 TUc is established for the discharge of effluent through Discharge Point 001. b. Sampling. The Discharger shall collect grab samples of the effluent at EFF-001, as specified in Table E-3 above, for critical life stage toxicity testing as indicated below. c. Test Species. The test species for chronic toxicity screening shall include a vertebrate, invertebrate, and an aquatic plant as identified in Table E-4 below. The Executive Officer may change the test species if data suggest that another test species is more sensitive to the discharge. After a three-month screening period, monitoring may be reduced to the most sensitive species. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-7 Table E-4. Short-Term Methods for Estimating Chronic Toxicity – Fresh Water Species Scientific Name Effect Test Duration (days) Fathead Minnow Pimephales promelas Larval Survival and Growth 7 Water Flea Ceriodaphnia dubia Survival; number of young 6 to 8 days Green Alga Selenastrum capricornutum Growth Rate 4 days d. Methodology. Sample collection, handling, and preservation shall be in accordance with USEPA protocols. In addition, bioassays shall be conducted in compliance with the most recently promulgated test methods, as shown in Appendix E-1 and Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms, currently third edition (EPA-821-R-02- 014) and Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, currently fourth Edition (EPA-821-R- 02-013), with exceptions granted the Discharger by the Executive Officer and the Environmental Laboratory Accreditation Program (ELAP). e. Dilution Series. The Discharger shall conduct tests at 100%, 85%, 70%, 50%, and 25%. The “%” represents percent effluent as discharged. The Discharger may use the biological buffer MOPS (3-(N-Morpholino)propanesulfonic Acid) to control pH drift and ammonia toxicity caused by increasing pH during the test. 2. Chronic Toxicity Reporting Requirements a. Routine Reporting. Toxicity test results for the current reporting period shall include, at a minimum, for each test: i. Sample dates ii. Test initiation date iii. Test species iv. End point values for each dilution (e.g., number of young, growth rate, percent survival) v. NOEC values in percent effluent vi. IC15, IC25, IC40, and IC50 values (or EC15, EC25 ... etc.) in percent effluent vii. TUc values (100/NOEC, 100/IC25, or 100/EC25) viii. Mean percent mortality (±s.d.) after 96 hours in 100% effluent (if applicable) ix. NOEC and LOEC values for reference toxicant tests x. IC50 or EC50 values for reference toxicant test xi. Available water quality measurements for each test (pH, dissolved oxygen, temperature, conductivity, hardness, salinity, ammonia) b. Compliance Summary. The results of the chronic toxicity testing shall be provided in the next Self-Monitoring Report and shall include a summary table of chronic toxicity data from at least eleven of the most recent samples. The information in the table shall include the items listed above under 2.a. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-8 C. Quality Assurance 1. For the acute toxicity testing using a t-test, two dilutions shall be used, i.e., 100 percent effluent and a control (when a t-test is used instead of an LC50). 2. If organisms are not cultured in-house, concurrent testing with a referenced toxicant shall be conducted. Where organisms are cultured in-house, monthly reference toxicant testing is sufficient. Reference toxicant tests also shall be conducted using the same test conditions as the effluent toxicity tests (e.g., same test duration, etc.). 3. If either the reference toxicant test or effluent test does not meet all test acceptability criteria (TAC) as specified in the toxicity test references, then the Discharger must resample and retest within 15 working days or as soon as possible. The retesting period begins when the Discharger collects the first sample required to complete the retest. 4. The reference toxicant and effluent tests must meet the upper and lower bounds on test sensitivity as determined by calculating the percent minimum significant difference (PMSD) for each test result. The test sensitivity bound is specified for each test method in the respective methods manuals. D. Accelerated Monitoring Requirements 1. When acute toxicity is detected in the effluent or when the chronic toxicity trigger of 1 TUc is exceeded during regular toxicity monitoring, and the testing meets all test acceptability criteria, the Discharger shall initiate accelerated monitoring to confirm the effluent toxicity. 2. The Discharger shall implement an accelerated monitoring frequency consisting of performing three toxicity tests in a six-week period following the first failed test results. 3. If implementation of the Discharger’s Toxicity Reduction Evaluation (TRE) work plan indicates the source of the exceedance of the effluent limitation or toxicity trigger (for instance, a temporary plant upset), then only one additional test is necessary. If exceedance of the effluent limitation or toxicity trigger is detected in this test, the Discharger will continue with accelerated monitoring requirements or implement the Toxicity Identification and Toxicity Reduction Evaluations. 4. If none of the three tests indicated exceedance of the effluent limitation or toxicity trigger, then the Discharger may return to the normal bioassay testing frequency. E. Conducting Toxicity Identification Evaluation (TIE) and Toxicity Reduction Evaluation (TRE) 1. A Toxicity Identification Evaluation (TIE) shall be triggered if testing from the accelerated monitoring frequency indicates any of the following: a. Two of the three accelerated toxicity tests are reported as failed tests meeting any of the conditions specified in Attachment E, section V.D. b. The TIE shall be initiated within 15 days following failure of the second accelerated monitoring test. c. If a TIE is triggered prior to the completion of the accelerated testing, the accelerated testing schedule may be terminated, or used as necessary in performing the TIE. 2. The TIE shall be conducted to identify and evaluate toxicity in accordance with procedures recommended by the United States Environmental Protection Agency (USEPA) which include the following: CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-9 a. Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents, Phase I, (USEPA, 1992a); b. Methods for Aquatic Toxicity Identification Evaluations: Phase I Toxicity Characterization Procedures, Second Edition (USEPA, 1991a); c. Methods for Aquatic Toxicity Identification Evaluations: Phase II Toxicity Identification Procedures for Sampling Exhibiting Acute and Chronic Toxicity (USEPA, 1993a); and d. Methods for Aquatic Toxicity Identification Evaluations: Phase III Toxicity Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity (USEPA, 1993b). 3. As part of the TIE investigation, the Discharger shall be required to implement its TRE work plan. The Discharger shall take all reasonable steps to control toxicity once the source of the toxicity is identified. A failure to conduct required toxicity tests or a TRE within a designated period shall result in the establishment of numerical effluent limitations for chronic toxicity in a permit or appropriate enforcement action. Recommended guidance in conducting a TRE includes the following: a. Toxicity Reduction Evaluation Guidance for Municipal Wastewater Treatment Plants, August 1999, EPA/833B-99/002; and b. Clarifications Regarding Toxicity Reduction and Identification Evaluations in the National Pollutant Discharge Elimination System Program dated March 27, 2001, USEPA Office of Wastewater Management, Office of Regulatory Enforcement. VI. LAND DISCHARGE MONITORING REQUIREMENTS – NOT APPLICABLE VII. RECYCLING MONITORING REQUIREMENTS – NOT APPLICABLE VIII. RECEIVING WATER MONITORING REQUIREMENTS A. Monitoring Location RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, RSW-008 1. The Discharger shall monitor the receiving water at Monitoring Locations RSW -001, RSW -002, RSW -003, RSW -004, RSW -005, RSW -006, RSW -007, AND RSW -008 as follows: Table E-5. Receiving Water Monitoring Requirements Parameter Units Sample Type [1] Sampling Station Minimum Sampling Frequency Flow [2] cfs Instantaneous 4, 5, 7, 8 1/Week, Apr – Oct Flow MGD Instantaneous 4, 5, 7, 8 1/Week, Apr – Oct [3] Turbidity [2] NTU Grab 4, 5 1/Week Color [2] Units Grab 4, 5 1/Week pH [2] [4] s.u. Grab 4, 5 1/Week Dissolved Oxygen mg/L Grab 4, 5 1/Week Temperature [4] °C Grab 4, 5 1/Week Un-Ionized mg/L calculated 4, 5 1/Month CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-10 Ammonia [4] Total Dissolved Solids mg/L Grab 4, 5 1/Quarter Sodium mg/L Grab 4, 5 1/Quarter Chloride mg/L Grab 4, 5 1/Quarter pH [4] s.u. Grab 5, 7, 8 1/Month Nitrate as N mg/L Grab 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 5, 7, 8 1/Month Total Phosphate as P mg/L Grab 5, 7, 8 1/Month Algal description [5] Visual observation Grab 5, 7, 8 1/Month Nitrite as N mg/L Grab 5, 7, 8 1/Month Ammonia as N mg/L Grab 5, 7, 8 1/Month TKN as N mg/L Grab 5, 7, 8 1/Month Dissolved Orthophosphate as P mg/L Grab 5, 7, 8 1/Month [1] Samples shall be obtained only when safe to do so. [2] The San Luis Obispo Creek flow rate shall determine the upstream and downstream stations where these constituents shall be monitored, as follows. If the creek flows underground between Monitoring Location RSW-002 and the discharge point, samples shall be obtained from Monitoring Location RSW-002. If the creek flows aboveground from Monitoring Location RSW-002 to the discharge point, samples shall be obtained from Monitoring Location RSW-004. In either case, Monitoring Location RSW-005 shall be the downstream location. [3] Sampling shall be concurrent with sampling of effluent for ammonia. [4] Temperature and pH are to be measured at the same time the Total Ammonia sample is collected. Results shall be used to calculate and report Un-Ionized Ammonia concentrations. [5] Narrative description of algae present at the monitoring location shall include: algal color, location with respect to stream banks and depth of water, and appearance (filamentous, matting, attached, etc., percent coverage of water surface). IX. OTHER MONITORING REQUIREMENTS A. Solids/Biosolids Monitoring, Notification, and Reporting 1. Biosolids Monitoring a. Biosolids shall be tested for the metals required in 40 C.F.R. § 503.16 (for land application) or 40 C.F.R. § 503.26 (for surface disposal), using the methods in Test Methods for Evaluating Solid Waste, Physical/Chemical Methods (SW -846), as required in 40 C.F.R. § 503.8(b)(4), at the following minimum frequencies: Volume (dry metric tons) [1] Sampling and Analysis Frequency [2] 0-290 Once per year 290-1500 Once per quarter 1500-15000 Once per 60 days > 15000 Once per month [1] For accumulated, previously untested biosolids, the Discharger shall develop a representative sampling plan, including number and location of sampling points, and collect representative samples. [2] Test results shall be expressed in mg pollutant per kg biosolids on a 100% dry weight basis. Biosolids to be land applied shall be tested for organic-N, ammonium-N, and nitrate-N at the frequencies required above CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-11 b. Prior to land application, the Discharger shall demonstrate that the biosolids meet Class A or Class B pathogen reduction levels by one of the methods listed in 40 C.F.R. § 503.32. Prior to disposal in a surface disposal site, the Discharger shall demonstrate that the biosolids meet Class B levels or shall ensure that the site is covered at the end of each operating day. If pathogen reduction is demonstrated using a “Process to Significantly/Further Reduce Pathogens”, the Discharger shall maintain daily records of the operating parameters used to achieve this reduction. If pathogen reduction is demonstrated by testing for fecal coliforms and/or pathogens, samples must be drawn at the frequency in 11(a) above. For fecal coliform, at least seven grab samples must be drawn during each monitoring event and a geometric mean calculated from these seven samples. c. For biosolids that are land applied or placed in a surface disposal site, the Discharger shall track and keep records of the operational parameters used to achieve Vector Attraction Reduction requirements in 40 C.F.R. § 503.33(b). d. Class 1 facilities (facilities with pretreatment programs or others designated as Class 1 by the Regional Administrator) and Federal facilities with greater than five million gallons per day (MGD) influent flow shall sample biosolids for pollutants listed under Section 307(a) of the Clean Water Act (as required in the pretreatment section of the permit for POTW’s with pretreatment programs). Class 1 facilities and Federal facilities greater than five MGD shall test dioxins/dibenzofurans using a detection limit of less than one pg/g at the time of their next priority pollutant scan if they have not done so within the past five years, and once per five years thereafter. e. The biosolids shall be tested annually, or more frequently if necessary, to determine hazardousness in accordance 40 C.F.R. part 261. f. If biosolids are placed in a surface disposal site (dedicated land disposal site or monofill), a qualified groundwater scientist shall develop a groundwater monitoring program for the site, or shall certify that the placement of biosolids on the site will not contaminate an aquifer. g. Biosolids placed in a municipal landfill shall be tested by the Paint Filter Liquids Test (EPA Method 9095) at the frequency in 11 (a) above or more often if necessary to demonstrate that there are no free liquids. 2. Biosolids Notification The Discharger, either directly or through contractual arrangements with their biosolids management contractors, shall comply with the following notification requirements: a. Notification of non-compliance: The Discharger shall notify U.S. EPA Region 9, the Central Coast Regional Board, and the Regional Board located in the region where the biosolids are used or disposed, of any non-compliance within 24 hours if the non-compliance may seriously endanger health or the environment. For other instances of non-compliance, the Discharger shall notify U.S. EPA Region 9 and the affected Regional Boards of the non-compliance in writing within five working days of becoming aware of the non-compliance. The Discharger shall require their biosolids management contractors to notify U.S. EPA Region 9 and the affected Regional Boards of any non-compliance within the same timeframes. See Attachment D for Regional Board contact information. b. If biosolids are shipped to another State or to Indian Lands, the Discharger must send 60 days prior notice of the shipment to the permitting authorities in the CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-12 receiving State or Indian Land (the U.S. EPA Regional Office for that area and the State/Indian authorities). c. For land application: Prior to reuse of any biosolids from this facility to a new or previously unreported site, the Discharger shall notify U.S. EPA and Regional Board. The notification shall include a description and topographic map of the proposed site(s), names and addresses of the applier, and site owner and a listing of any state or local permits which must be obtained. The plan shall include a description of the crops or vegetation to be grown, proposed loading rates and determination of agronomic rates. If any biosolids within a given monitoring period do not meet 40 C.F.R. § 503.13 metals concentration limits, the Discharger (or its contractor) must pre-notify U.S. EPA, and determine the cumulative metals loading at that site to date, as required in 40 C.F.R. § 503.12. d. The Discharger shall notify the applier of all the applier's requirements under 40 C.F.R. part 503, including the requirement that the applier certify that the management practices, site restrictions, and any applicable vector attraction reduction requirements have been met. The Discharger shall require the applier to certify at the end of 38 months following application of Class B biosolids that the harvesting restrictions in effect for up to 38 months have been met. e. For surface disposal: Prior to disposal to a new or previously unreported site, the Discharger shall notify U.S. EPA and the Regional Board. The notice shall include description and topographic map of the proposed site, depth to groundwater, whether the site is lined or unlined, site operator, site owner, and any state or local permits. The notice shall describe procedures for ensuring public access and grazing restrictions for three years following site closure. The notice shall include a groundwater monitoring plan or description of why groundwater monitoring is not required. 3. Biosolids Reporting The Discharger shall submit an annual biosolids report to the U.S. EPA Region 9 Biosolids Coordinator and Regional Board by February 19th of each year for the period covering the previous calendar year. The report shall include: a. The amount of biosolids generated during the reporting period, in dry metric tons, and the amount accumulated from previous years; b. Results of all pollutant and pathogen monitoring required in Item 12 above and the Monitoring and Reporting Program of this Order. Results must be reported on a 100% dry weight basis for comparison with 40 C.F.R. part 503 limits; c. Descriptions of pathogen reduction methods and vector attraction reduction methods, including supporting time and temperature data, and certifications, as required in 40 C.F.R. §§ 503.17 and 503.27; d. Names, mailing addresses, and street addresses of persons who received biosolids for storage, further treatment, disposal in a municipal waste landfill, or for other use or disposal methods not covered above, and volumes delivered to each. e. For land application sites, the following information must be submitted by the Discharger, unless the Discharger requires its biosolids management contractors to report this information directly to the U.S. EPA Region 9 Biosolids Coordinator: CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-13 i. Locations of land application sites (with field names and numbers) used that calendar year, size of each field applied to, applier, and site owner. ii. Volumes applied to each filed (in wet tons and dry metric tons), nitrogen applied, calculated plant available nitrogen; iii. Crop planted, dates of planting and harvesting; iv. For any biosolids exceeding 40 C.F.R. § 503.13 Table 3 metals concentrations: the locations of sites where applied and cumulative metals loading at that site to date; v. Certifications of management practices in 40 C.F.R. § 503.14; and vi. Certifications of site restrictions in 40 C.F.R. § 503(b)(5). f. For surface disposal sites: i. Locations of sites, site operator, site owner, size of parcel on which disposed; ii. Results of any required groundwater monitoring; iii. Certifications of management practices in 40 C.F.R. § 503.24; and iv. For closed sites, date of site closure and certifications of management practices for the three years following site closure. g. For all biosolids used or disposed at the Permittee's facilities, the site and management practice information and certification required in 40 C.F.R. §§ 503.17 and 503.27; and h. For all biosolids temporarily stored, the information required in 40 C.F.R. § 503.20 required to demonstrate temporary storage. Reports shall be submitted to: Regional Biosolids Coordinator USEPA (WTR-7) 75 Hawthorne Street San Francisco, CA 94105-3901 Executive Officer Central Coast Regional Water Quality Control Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93455-5411 i. All the requirements of 40 C.F.R. part 503 and 23 CCR 15 are enforceable by the U.S. EPA and this Regional Board whether or not the requirements are stated in an NPDES permit or any other permit issued to the Discharger. B. Pretreatment Monitoring By February 1st of each year, the Discharger shall submit an annual report to the Central Coast Regional Board, State Board, and USEPA describing the Discharger's pretreatment activities over the previous calendar year. In the event that the Discharger is not in compliance with any conditions or requirements of this permit affected by the pretreatment program, including any noncompliance with pretreatment audit or compliance inspection requirements, then the Discharger shall also include the reasons for noncompliance and state CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-14 how and when the Discharger shall comply with such conditions and requirements. This report shall contain, but not be limited to, the following information: 1. A summary of analytical results from representative, flow-proportioned, 24-hour composite samples of the plant's influent and effluent for those pollutants USEPA has identified under Section 307(a) of the CWA which are known or suspected to be discharged by industrial users. The Discharger is not required to sample and analyze for asbestos until USEPA promulgates an applicable analytical technique under 40 C.F.R. part 136. 2. A discussion of upset, interference, or pass-through incidents, if any, at the POTW which the Discharger knows or suspects were caused by industrial users of the POTW system. The discussion shall include the reasons why the incidents occurred, corrective actions taken and, if known, the name and address of the industrial user(s) responsible. Discussions shall also include a review of applicable pollutant limitations to determine whether any additional limitations or changes to existing requirements may be necessary to prevent pass-through, interference, or noncompliance with sludge disposal requirements. 3. The cumulative number of industrial users that the Discharger has notified regarding Baseline Monitoring Reports, and the cumulative number of industrial user responses. 4. An updated list of the Discharger's industrial users, including their names and addresses, or a list of deletions and additions keyed to a previously submitted list. The Discharger shall provide a brief explanation for each deletion. The list shall identify the industrial users subject to Federal Categorical Standards by specifying which set(s) of standards are applicable. The list shall indicate which categorical industries, or specific pollutants from each industry, are subject to local limitations that are more stringent than the Federal Categorical Standards. The Discharger shall also list the non-categorical industrial users that are subject only to local discharge limitations. The Discharger shall characterize the compliance status of each industrial user by employing the following descriptions: a. In compliance with Baseline Monitoring Report requirements (where applicable); b. Consistently achieving compliance; c. Inconsistently achieving compliance; d. Significantly violated applicable pretreatment requirements as defined by 40 C.F.R. § 403.8(f)(2)(vii); e. On a schedule to achieve compliance (include the date final compliance is required); f. Not achieving compliance and not on a compliance schedule; or g. The Discharger does not know the industrial user’s compliance status. 5. A quarterly report describing the compliance status of any industrial user characterized by descriptions in Items 4(c) through (g) above shall be submitted to the Central Coast Water Board, State Board, and USEPA. The report shall identify the specific compliance status of each applicable industrial user. This quarterly reporting requirement shall commence upon issuance of this Order and Permit. Quarterly reports shall be submitted May 1, August 1, November 1, and February 1. Quarterly reports shall briefly describe POTW compliance with audit/pretreatment compliance inspection requirements. If none of the aforementioned conditions exist, at a minimum, a letter indicating that all industries CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-15 are in compliance and no violations or changes to the pretreatment program have occurred during the quarter must be submitted. 6. A summary of inspection and sampling activities conducted by the Discharger during the past year to gather information and data regarding industrial users. The summary shall include: a. Names and addresses of the industrial users subject to surveillance by the Discharger and an explanation of whether they were inspected, sampled, or both, and the frequency of these activities at each user; and b. Conclusions or results from the inspection or sampling of each industrial user. 7. A summary of compliance and enforcement activities during the past year. The summary shall include names and addresses of the industrial users affected by the following actions: a. Warning letters or notices of violation regarding the industrial users' apparent noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the apparent violation concerned the Federal Categorical Standards or local discharge limitations; b. Administrative Orders regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; c. Civil actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; d. Criminal actions regarding the industrial user's noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned Federal Categorical Standards or local discharge limitations; e. Assessment of monetary penalties. For each industrial user, identify the amount of the penalties; f. Restriction of flow to the POTW; or g. Disconnection from discharge to the POTW . 8. Description of any significant changes in operating the pretreatment program which differ from the information in the Discharger's Approved POTW Pretreatment Program, including but not limited to changes concerning: the program's administrative structure; local industrial discharge limitations; monitoring program or monitoring frequencies; legal authority or enforcement policy; funding mechanisms; resource requirements; or staffing levels. 9. A summary of the annual pretreatment budget, including the costs of pretreatment program functions and equipment purchases. 10. A summary of public participation activities to involve and inform the public. 11. Reports shall be signed by a principal executive officer, ranking elected official, or other duly authorized employee if such employee is responsible for overall operation of the CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-16 POTW. Signed copies of these reports shall be submitted to the USEPA and the State Board at the following addresses: State Water Resources Control Board Regulation Unit P.O. Box 100 Sacramento, CA 95812-0100 US EPA, Region 9 Clean Water Act Compliance Office 75 Hawthorne Street (WTR-7) San Francisco, CA 94105-3901 For reporting to the Central Coast Water Board, reports shall be uploaded using the State Water Board’s California Integrated Water Quality System (CIWQS) Program website (http://www.waterboards.ca.gov/ciwqs/index.html). X. REPORTING REQUIREMENTS A. General Monitoring and Reporting Requirements The Discharger shall comply with all Standard Provisions (Attachment D) related to monitoring, reporting, and recordkeeping. B. Self-Monitoring Reports (SMRs) 1. The Discharger shall electronically submit SMRs using the CIWQS Program website. The CIWQS website will provide additional information for SMR submittal in the event there will be a planned service interruption for electronic submittal. 2. The Discharger shall report in the SMR the results for all monitoring specified in this MRP under sections III through IX. The Discharger shall submit monthly and annual SMRs including the results of all required monitoring using U.S. EPA-approved test methods or other test methods specified in this Order. SMRs are to include all new monitoring results obtained since the last SMR was submitted. If the Discharger monitors any pollutant more frequently than required by this Order, the results of this monitoring shall be included in the calculations and reporting of the data submitted in the SMR. 3. Monitoring periods and reporting for all required monitoring shall be completed according to the following schedule: CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-17 Table E-6. Monitoring Periods and Reporting Schedule SMR Name Permit Section for Monitoring & Sampling Data Included in Report SMR Submittal Frequencies SMR Due Date NPDES Monitoring Report- Monthly MRP Sections III (Influent), IV (Effluent) and VIII (Receiving Water) Monthly First day of second calendar month following period of sampling (first report due February 1st 2015) NPDES Monitoring Report- Quarterly MRP Section IV (Effluent) and VIII (Receiving Water) Quarterly February 1, May 1, August 1, and November 1st (first report due Feb 1st 2015) NPDES Monitoring Report- Annual MRP Section IV (Effluent), V (Toxicity) and VIII (Receiving Water) Annually February 1st, (first report due Feb 1st 2015 following October 2014 sampling) Summary Report[1] Attachment D, Standard Provision VIII.D.8 and Salt and Nutrient Management Plan Order Section VI.C.3.a Annually February 15th Facilities Evaluation Order Section VI.C.2.b Special Provisions Once per permit March 1, 2017 Effluent pH Evaluation Order Section VI.C.2.c Special Provisions Once per permit February 1, 2016 Pretreatment- Quarterly Order Section IX.B (pretreatment) Quarterly February 1, May 1, August 1, and November 1st (first report due Feb 1st 2015) Pretreatment- Annual Order Section IX.B (pretreatment) Annually February 1st Biosolids (Sludge) Technical Report MRP Section IX.A (Biosolids) Annually February 19th [1] Based on Discharger’s request, the standard February 1st deadline for this Summary Report has been revised to February 15th to accommodate work on year-end sampling and pretreatment reporting. 4. Reporting Protocols. The Discharger shall report with each sample result the applicable Reporting Level (RL) and the current Method Detection Limit (MDL), as determined by the procedure in 40 C.F.R. part 136. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-18 The Discharger shall report the results of analytical determinations for the presence of chemical constituents in a sample using the following reporting protocols: a. Sample results greater than or equal to the RL shall be reported as measured by the laboratory (i.e., the measured chemical concentration in the sample). b. Sample results less than the RL, but greater than or equal to the laboratory’s MDL, shall be reported as “Detected, but Not Quantified,” or DNQ. The estimated chemical concentration of the sample shall also be reported. For the purposes of data collection, the laboratory shall write the estimated chemical concentration next to DNQ. The laboratory may, if such information is available, include numerical estimates of the data quality for the reported result. Numerical estimates of data quality may be percent accuracy (± a percentage of the reported value), numerical ranges (low to high), or any other means considered appropriate by the laboratory. c. Sample results less than the laboratory’s MDL shall be reported as “Not Detected,” or ND. d. Dischargers are to instruct laboratories to establish calibration standards so that the ML value (or its equivalent if there is differential treatment of samples relative to calibration standards) is the lowest calibration standard. At no time is the Discharger to use analytical data derived from extrapolation beyond the lowest point of the calibration curve. 5. The Discharger shall submit SMRs in accordance with the following requirements: a. The Discharger shall arrange all reported data in a tabular format. The data shall be summarized to clearly illustrate whether the facility is operating in compliance with interim and/or final effluent limitations. The Discharger is not required to duplicate the submittal of data that is entered in a tabular format within CIWQS. When electronic submittal of data is required and CIWQS does not provide for entry into a tabular format within the system, the Discharger shall electronically submit the data in a tabular format as an attachment. b. Discharger shall include electronic pdfs of all lab data sheets and chain of custodies for analytical data as attachments to the SMRs. Additionally, any calculations used to provide calculated values (e.g., removal efficiencies, coliform medians, average monthly values, average weekly values, intake credits, etc.) shall be attached such that the data and/or assumptions used can be validated. c. In the SMR, the Discharger shall clearly identify violations of the WDRs and discuss corrective actions taken or planned and the proposed time schedule for corrective actions. Identified violations must include a description of the requirement that was violated and a description of the violation. C. Discharge Monitoring Reports (DMRs) 1. At any time during the term of this permit, the State or Central Coast Water Board may notify the Discharger to electronically submit DMRs. Until such notification is given specifically for the submittal of DMRs, the Discharger shall submit DMRs in accordance with the requirements described below. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT E – MRP E-19 2. DMRs must be signed and certified as required by the standard provisions (Attachment D). The Discharger shall submit the original DMR and one copy of the DMR to the address listed below: 3. All discharge monitoring results must be reported on the official U.S. EPA pre-printed DMR forms (EPA Form 3320-1) or on self-generated forms that follow the exact same format of EPA Form 3320-1. D. Other Reports 1. Unless otherwise noted, with the next SMR, the Discharger shall report the results of any special monitoring, TREs, or other data or information that results from the Special Provisions, section V. C, of the Order. STANDARD MAIL FEDEX/UPS/ OTHER PRIVATE CARRIERS State Water Resources Control Board Division of Water Quality c/o DMR Processing Center PO Box 100 Sacramento, CA 95812-1000 State Water Resources Control Board Division of Water Quality c/o DMR Processing Center 1001 I Street, 15th Floor Sacramento, CA 95814 CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-1 F. ATTACHMENT F – FACT SHE ET Contents I. Permit Information ...................................................................................................................... F-3 II. Facility Description ..................................................................................................................... F-4 A. Description of Wastewater and Biosolids Treatment and Controls ...................................... F-4 B. Discharge Points and Receiving Waters ............................................................................. F-4 C. Summary of Existing Requirements and Self-Monitoring Report (SMR) Data ..................... F-5 D. Compliance Summary ......................................................................................................... F-7 E. Planned Changes ............................................................................................................... F-7 III. Applicable Plans, Policies, and Regulations ............................................................................... F-7 A. Legal Authorities ................................................................................................................. F-7 B. California Environmental Quality Act (CEQA) ...................................................................... F-7 C. State and Federal Laws, Regulations, Policies, and Plans .................................................. F-8 D. Impaired Water Bodies on CWA 303(d) List ........................................................................ F-9 E. Other Plans, Policies and Regulations ................................................................................ F-9 IV. Rationale For Effluent Limitations and Discharge Specifications .............................................. F-10 A. Discharge Prohibitions ...................................................................................................... F-10 B. Technology-Based Effluent Limitations ............................................................................. F-11 1. Scope and Authority ..................................................................................................... F-11 2. Applicable Technology-Based Effluent Limitations ........................................................ F-11 C. Water Quality-Based Effluent Limitations (WQBELs) ........................................................ F-13 1. Scope and Authority ..................................................................................................... F-13 2. Applicable Beneficial Uses and Water Quality Criteria and Objectives .......................... F-13 3. Determining the Need for WQBELs .............................................................................. F-14 4. WQBEL Calculations .................................................................................................... F-19 5. Whole Effluent Toxicity (WET) ...................................................................................... F-20 6. Basin Plan .................................................................................................................... F-22 D. Final Effluent Limitation Considerations ............................................................................ F-24 1. Anti-Backsliding Requirements ..................................................................................... F-24 2. Antidegradation Policies ............................................................................................... F-24 3. Stringency of Requirements for Individual Pollutants .................................................... F-25 4. Summary of Final Effluent Limitations – Discharge Point 001 ....................................... F-25 E. Interim Effluent Limitations ................................................................................................ F-27 F. Land Discharge Specifications – Not Applicable ............................................................... F-27 G. Recycling Specifications ................................................................................................... F-27 V. Rationale for Receiving Water Limitations ................................................................................ F-27 A. Surface Water ................................................................................................................... F-27 B. Groundwater ..................................................................................................................... F-27 VI. Rationale For Monitoring and Reporting Requirements ............................................................ F-27 VII. Rationale for Provisions ........................................................................................................... F-29 A. Standard Provisions .......................................................................................................... F-29 B. Special Provisions............................................................................................................. F-29 1. Reopener Provisions .................................................................................................... F-29 2. Special Studies and Additional Monitoring Requirements ............................................. F-29 3. Best Management Practices and Pollution Prevention .................................................. F-30 4. Construction, Operation, and Maintenance Specifications ............................................ F-30 5. Special Provisions for Municipal Facilities (POTWs Only) ............................................. F-30 CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-2 6. Other Special Provisions .............................................................................................. F-31 7. Compliance Schedules – Not Applicable ...................................................................... F-31 VIII. Public Participation ................................................................................................................... F-31 A. Notification of Interested Parties ....................................................................................... F-31 B. Written Comments ............................................................................................................ F-32 C. Public Hearing .................................................................................................................. F-34 D. Reconsideration of Waste Discharge Requirements ......................................................... F-34 E. Information and Copying ................................................................................................... F-34 F. Register of Interested Persons .......................................................................................... F-35 G. Additional Information ....................................................................................................... F-35 Tables Table F-1. Facility Information ......................................................................................................... F-3 Table F-2. Historic Effluent Limitations and Monitoring Data ............................................................ F-5 Table F-3. Compliance Summary .................................................................................................... F-7 Table F-4. Basin Plan Beneficial Uses ............................................................................................. F-8 Table F-5. Technology-Based Effluent Limitations ......................................................................... F-13 Table F-6. Summary of RPA Results ............................................................................................. F-15 Table F-9. Calculation of Human Health WQBELs ......................................................................... F-20 Table F-10. Summary of Final Effluent Limitations ........................................................................... F-26 CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-3 ATTACHMENT F – FACT SHEET As described in section I of this Order, the Central Coast Water Board incorporates this Fact Sheet as findings of the Central Coast Water Board supporting the issuance of this Order. This Fact Sheet includes the legal requirements and technical rationale that serve as the basis for the requirements of this Order. This Order has been prepared under a standardized format to accommodate a broad range of discharge requirements for dischargers in California. Only those sections or subsections of this Order that are specifically identified as “not applicable” have been determined not to apply to this Discharger. Sections or subsections of this Order not specifically identified as “not applicable” are fully applicable to this Discharger. I. PERMIT INFORMATION The following table summarizes administrative information related to the facility. Table F-1. Facility Information WDID 3 400107001 Discharger City of San Luis Obispo Name of Facility Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 David Hix Facility Contact, Title and Phone David Hix, Deputy Director, Utilities, Wastewater, (805) 781-7039 Authorized Person to Sign and Submit Reports David Hix, Deputy Director, Utilities, Wastewater, (805) 781-7039 Mailing Address 879 Morro Street, San Luis Obispo, CA 93401 Billing Address SAME Type of Facility POTW Major or Minor Facility Major Threat to Water Quality 2 Complexity A Pretreatment Program Y Recycling Requirements Master Permit for Reclamation Order No. R3-2003-0081 Facility Permitted Flow 5.1 million gallons per day (MGD) Facility Design Flow 5.1 million gallons per day (MGD) Watershed Estero Bay Hydrologic Unit Receiving Water San Luis Obispo Creek Receiving Water Type Inland surface water A. The City of San Luis Obispo (hereinafter Discharger) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (hereinafter Facility), a wastewater treatment facility. For the purposes of this Order, references to the “discharger” or “permittee” in applicable federal and state laws, regulations, plans, or policy are held to be equivalent to references to the Discharger herein. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-4 B. The Facility discharges wastewater to San Luis Obispo Creek, a water of the United States. The Discharger was previously regulated by Order No. R3-2002-0043, National Pollutant Discharge Elimination System (NPDES) Permit No. CA0049224, adopted on March 31, 2002, and modified on March 25, 2005, which has been administratively extended. Attachment B provides a map of the area around the Facility. Attachment C provides a flow schematic of the Facility. Prior to making any change in the point of discharge, place of use, or purpose of use of treated wastewater that results in a decrease of flow in any portion of a watercourse, the Discharger must file a petition with the State Water Board, Division of Water Rights, and receive approval for such a change. The State Water Board retains the jurisdictional authority to enforce such requirements under Water Code section 1211. C. The Discharger filed a report of waste discharge and submitted an application for reissuance of its WDRs and NPDES permit on November 29, 2006. II. FACILITY DESCRIPTION The Discharger owns and operates a wastewater collection, treatment, and disposal system for the City of San Luis Obispo, California Polytechnic State University, and the San Luis Obispo Airport, including a population of approximately 40,000 individuals. The WRF design daily average flow capacity is 5.1 million gallons per day (MGD). A. Description of Wastewater and Biosolids Treatment and Controls The Discharger owns and operates a publicly owned treatment works. The treatment system consists of mechanical screening, grit removal, primary settling, biofiltration, secondary settling, nitrification, final settling, cooling using evaporative cooling towers, dual media filtration, and chlorination/dechlorination. Solids are thickened in a dissolved air flotation thickener and stabilized in anaerobic digesters. During the drier parts of the year the sludge is placed in drying beds, dried and stockpiled to await disposal. A belt press is used for the remainder of the year. Biosolids are hauled off- site by a contractor for composting. Finished compost is sold to agricultural, horticultural, and/or landscape operations. California Polytechnic State University and the San Luis Obispo County Airport retain ownership and direct responsibility for wastewater collection and transport systems up to the point of discharge into the wastewater treatment plant and/or interceptors owned and operated by the City of San Luis Obispo. It is incumbent upon these local sewering entities to protect the environment to the greatest degree possible and ensure their local collection systems, as well as the receiving sewerage system, are protected and utilized properly. This responsibility includes preventing overflows and may include restricting or prohibiting the volume, type, or concentration of wastes that might be added to the system. B. Discharge Points and Receiving Waters The Facility is located in Section 10, T31S, R12E, MDB&M, as shown in Attachment B to this Order. Treated municipal wastewater is discharged at Discharge Point 001 to San Luis Obispo Creek, a water of the United States, at a latitude of 35° 14ʹ 10ʺ N and longitude 120° 40ʹ 45ʺ W. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-5 C. Summary of Existing Requirements and Self-Monitoring Report (SMR) Data Effluent limitations contained in the existing Order for discharges from Discharge Point 001 (Monitoring Location EFF-001) and representative monitoring data from the term of the previous Order (i.e., January 2008 through December 2012) are as follows: Table F-2. Historic Effluent Limitations and Monitoring Data Parameter Units Effluent Limitations Monitoring Data (January 2008- December 2012 Monthly Average Weekly Average Daily Maximum Instantaneous Maximum Highest Monthly Average Highest Weekly Average Highest Daily Discharge BOD5 mg/L 10 30 50 --- 13.6 13.7 NA lb/day [1] [2] [3] --- 374 804 NA % removal Not less than 85% removal rate 93.1[4] NA NA TSS mg/L 10 30 75 --- 19 24.9 NA lb/day [2] [3] [5] --- 673 2099 NA % removal Not less than 85% removal rate 95.6[6] NA NA Oil and Grease mg/L 5 --- 10 --- 6 NA 16 lb/day [7] --- [8] --- 405 NA 1372 Dissolved Oxygen mg/L --- --- --- 4.0 NA NA 0.3[9] pH s.u. Between 6.5 and 8.3 at all times 6.6 to 7.8 Fecal Coliform MPN/10 0 mL --- 2.2 --- --- --- 22 --- Total Coliform MPN/10 0 mL --- 23 --- 240 --- 7.9 130 Settleable Solids mL/L 0.1 --- --- --- NA NA < 0.1 Chlorodibro momethane [10] µg/L 0.4 --- 0.8 --- NA NA 13.8 Dichlorobro momethane [10] µg/L 0.6 --- 1.1 --- NA NA 30.8 Selenium µg/L 4.1 --- 8.2 --- 4.1 NA 4.1 Bromoform µg/L 4.3 --- 8.6 --- 1.9 NA 1.9 Cyanide µg/L 4.3 --- 8.6 --- 4.0 NA 4.0 Aluminum µg/L --- --- --- 1,000 NA NA 40 Barium µg/L --- --- --- 1,000 NA NA 36.2 Fluoride µg/L --- --- --- 2,000 NA NA 900 cis-1,2- Dichloroeth ylene µg/L --- --- --- 6 NA NA NA Methyl-tert- butyl ether µg/L --- --- --- 13 NA NA < 1 Styrene µg/L --- --- --- 100 NA NA < 0.5 Trichloroflu oromethan e µg/L --- --- --- 150 NA NA < 1 1,1,2-µg/L --- --- --- 1,200 NA NA < 0.5 CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-6 Parameter Units Effluent Limitations Monitoring Data (January 2008- December 2012 Monthly Average Weekly Average Daily Maximum Instantaneous Maximum Highest Monthly Average Highest Weekly Average Highest Daily Discharge Trichloro- 1,2,2- Trifluoroeth ane Xylenes µg/L --- --- --- 1,750 NA NA 0.5 Alachlor µg/L --- --- --- 2 NA NA < 0.2 Atrazine µg/L --- --- --- 3 NA NA < 0.5 Bentazon µg/L --- --- --- 18 NA NA < 2 Carbofuran µg/L --- --- --- 18 NA NA < 5 2,4-D µg/L --- --- --- 70 NA NA < 2 Dalapon µg/L --- --- --- 200 NA NA < 10 Dibromochl oropropane µg/L --- --- --- 0.2 NA NA NA Di (2- ethylhexyl) adipate µg/L --- --- --- 400 NA NA < 5 Di (2- ethylhexyl) phthalate µg/L --- --- --- 4 NA NA NA Dinoseb µg/L --- --- --- 7 NA NA < 1 Diquat µg/L --- --- --- 20 NA NA < 2 Endothall µg/L --- --- --- 100 NA NA < 40 Ethylene Dibromide µg/L --- --- --- 0.05 NA NA NA Glyphosate µg/L --- --- --- 700 NA NA < 20 Methoxychl or µg/L --- --- --- 40 NA NA < 0.1 Molinate µg/L --- --- --- 20 NA NA < 2 Oxamyl µg/L --- --- --- 200 NA NA < 5 Picloram µg/L --- --- --- 500 NA NA < 1 Simazine µg/L --- --- --- 4 NA NA < 1 Thiobencar b µg/L --- --- --- 70 NA NA < 1 2, 4, 5-TP (Silvex) µg/L --- --- --- 50 NA NA < 1 Footnotes to Table F-4: Source: San Luis Obispo Water Reclamation Facility Modified Order No. R3-2002-0043. Effluent data from January 2008 to December 2012 retrieved from CIWQS and ICIS. [1] Determined by multiplying 10 mg/L times the measured flow rate discharged to San Luis Obispo Creek. [2] Determined by multiplying 30 mg/L times the measured flow rate discharged to San Luis Obispo Creek. [3] Determined by multiplying 50 mg/L times the measured flow rate discharged to San Luis Obispo Creek. [4] This value represents the lowest reported value of the minimum percent removal of BOD. [5] Determined by multiplying 75 mg/L times the measured flow rate discharged to San Luis Obispo Creek. [6] This value represents the lowest reported value of the minimum percent removal of TSS. [7] Determined by multiplying 5 mg/L times the average monthly measured flow rate discharged to San Luis Obispo Creek. [8] Determined by multiplying 10 mg/L times the monthly average daily maximum measured flow rate discharged to San Luis Obispo Creek. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-7 [9] This value represents the lowest reported value of the minimum dissolved oxygen reported concentrations. [10] Final effluent limitations contained in Time Schedule Order R3-2010-0013. mg/L = milligrams per liter µg/L = micrograms per liter lb/day = pounds per day ND = non-detect NA = not available D. Compliance Summary A review of the available effluent monitoring data, submitted in the Discharger’s self- monitoring reports for the period from January 2008 through December 2012, indicate that the Discharger had effluent limitation violations for BOD, TSS, oil and grease, and fecal coliform. The values reported in exceedance of effluent limitations are summarized in the table below. Table F-3. Compliance Summary Monitoring Period Violation Type Pollutant Reported Value Permit Limitation Units March 2008 7-sample median Fecal Coliform 22 2.2 MPN/100 ml July 2008 Monthly Average BOD 13.6 10 mg/L December 2008 Monthly Average TSS 19 10 mg/L November 2009 Monthly Average Oil & Grease 6 5 mg/L January 2010 Daily Maximum Oil & Grease 16 10 mg/L December 2010 Monthly Average TSS 10.3 10 mg/L E. Planned Changes The Discharger will be upgrading the facility to address both nitrogen and trihalomethanes in order to meet the final effluent limitations in this permit. Nitrogen removal will address the new limitations incorporated as part of the implementation of the San Luis Obispo Creek Nutrient Total Maximum Daily Load (see discussion in Attachment F Section IV.C.3). Changes to the disinfection process will prevent the formation of trihalomethanes in the effluent. The City is in the process of studying and designing the upgrades. The City has adopted a rate structure in anticipation of facility upgrades. City staff will be working with the Central Coast Water Board during the duration of this permit term to implement those upgrades. III. APPLICABLE PLANS, POLICIES, AND REGULATIONS The requirements contained in this Order are based on the requirements and authorities described in this section. A. Legal Authorities This Order serves as WDRs pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA) and implementing regulations adopted by the U.S. EPA and chapter 5.5, division 7 of the Water Code (commencing with section 13370). It shall serve as an NPDES permit for point source discharges from this facility to surface waters. B. California Environmental Quality Act (CEQA) Under Water Code section 13389, this action to adopt an NPDES permit is exempt from the provisions of Chapter 3 of CEQA, (commencing with section 21100) of Division 13 of the Public Resources Code. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-8 C. State and Federal Laws, Regulations, Policies, and Plans 1. Water Quality Control Plan. The Central Coast Water Board has adopted the Water Quality Control Plan for the Central Coastal Basin (hereinafter Basin Plan), which designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for receiving waters within the Region. In addition, the Basin Plan implements State Water Board Resolution 88-63, which established state policy that all waters, with certain exceptions, should be considered suitable or potentially suitable for municipal or domestic supply. The Facility discharges to San Luis Obispo Creek. Beneficial uses applicable to San Luis Obispo Creek (below W. Marsh Street) are as follows: Table F-4. Basin Plan Beneficial Uses Discharge Point Receiving Water Name Beneficial Use(s) 001 San Luis Obispo Creek (below W. Marsh Street) Existing: Municipal and domestic (MUN); agricultural supply (AGR); ground water recharge (GWR); water contact recreation (REC1); non-contact water recreation (REC2); wildlife habitat (WILD); cold fresh water habitat (COLD); warm fresh water habitat (WARM); migration of aquatic organisms (MIGR); fish spawning, reproduction, and/or early development (SPWN); freshwater replenishment (FRESH); commercial and sport fishing (COMM). Intermittent: None. Potential: None. Groundwater throughout the Central Coast Region is suitable for agricultural water supply, municipal and domestic water supply, and industrial use. Requirements of this Order implement the Basin Plan. 2. Thermal Plan. The State Water Board adopted the Water Quality Control Plan for Control of Temperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of California (Thermal Plan) on January 7, 1971, and amended this plan on September 18, 1975. This plan contains temperature objectives for inland surface waters. 3. National Toxics Rule (NTR) and California Toxics Rule (CTR). U.S. EPA adopted the NTR on December 22, 1992, and later amended it on May 4, 1995 and November 9, 1999. About forty criteria in the NTR applied in California. On May 18, 2000, U.S. EPA adopted the CTR. The CTR promulgated new toxics criteria for California and, in addition, incorporated the previously adopted NTR criteria that were applicable in the state. The CTR was amended on February 13, 2001. These rules contain federal water quality criteria for priority pollutants. 4. State Implementation Policy. On March 2, 2000, the State Water Board adopted the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (State Implementation Policy or SIP). The SIP became effective on April 28, 2000, with respect to the priority pollutant criteria promulgated for California by the U.S. EPA through the NTR and to the priority pollutant objectives established by the Central Coast Water Board in the Basin Plan. The SIP became CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-9 effective on May 18, 2000, with respect to the priority pollutant criteria promulgated by the U.S. EPA through the CTR. The State Water Board adopted amendments to the SIP on February 24, 2005, that became effective on July 13, 2005. The SIP establishes implementation provisions for priority pollutant criteria and objectives and provisions for chronic toxicity control. Requirements of this Order implement the SIP. 5. Antidegradation Policy. Federal regulation 40 C.F.R. section 131.12 requires that the state water quality standards include an antidegradation policy consistent with the federal policy. The State Water Board established California’s antidegradation policy in State Water Board Resolution 68-16. Resolution 68-16 is deemed to incorporate the federal antidegradation policy where the federal policy applies under federal law. Resolution 68-16 requires that existing water quality be maintained unless degradation is justified based on specific findings. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the State and federal antidegradation policies. The permitted discharge must be consistent with the antidegradation provision of 40 C.F.R. section 131.12 and State Water Board Resolution 68-16. 6. Anti-Backsliding Requirements. Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. section 122.44(l) restrict backsliding in NPDES permits. These anti-backsliding provisions require that effluent limitations in a reissued permit must be as stringent as those in the previous permit, with some exceptions in which limitations may be relaxed. 7. Endangered Species Act Requirements. This Order does not authorize any act that results in the taking of a threatened or endangered species or any act that is now prohibited, or becomes prohibited in the future, under either the California Endangered Species Act (Fish and Game Code, §§ 2050 to 2097) or the Federal Endangered Species Act (16 U.S.C.A. §§ 1531 to 1544). This Order requires compliance with effluent limits, receiving water limits, and other requirements to protect the beneficial uses of waters of the state. The Discharger is responsible for meeting all requirements of the applicable Endangered Species Act. D. Impaired Water Bodies on CWA 303(d) List CWA section 303(d) requires states to identify specific water bodies where water quality standards are not expected to be met after implementation of technology-based effluent limitations on point sources. For all 303(d) listed water bodies and pollutants, the Regional Water Boards must develop and implement Total Maximum Daily Loads (TMDLs) that will specify Waste Load Allocations (WLAs) for point sources and Load Allocations (LAs) for non- point sources. The U.S. EPA approved the State’s 2010 303(d) list of impaired water bodies on November 12, 2010. The 2010 303(d) list identifies San Luis Obispo Creek, below West Osos Street is listed for chloride, chlorpyrifos, nitrate, nutrients, pathogens, and sodium. A TMDL for nitrate (reported analytically as nitrate-nitrogen) has been developed for the San Luis Obispo Creek, below West Marsh Street. Effluent limitations for nitrate-nitrogen are implemented in this Permit based on the Central Coast Water Board Resolution R3-2005- 0106 (TMDL for nitrate-nitrogen). E. Other Plans, Policies and Regulations 1. Storm Water Management. For the control of storm water discharged from the site of the wastewater treatment facilities, the Order requires the Discharger to seek authorization to discharge under and meet the requirements of the State Water Resource Control Board’s Water Quality Order No. 97-03-DWQ, NPDES General Permit No. CAS000001, CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-10 Waste Discharge Requirements for Discharges of Storm Water Associated with Industrial Activities Excluding Construction Activities, if applicable. 2. Statewide General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order No. 2006-0003-DWQ). The General Permit, adopted on May 2, 2006, is applicable to all “federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California.” The purpose of the General Permit is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger has obtained coverage under the General Permit. 3. Recycled Water Policy. The State Water Board’s Recycled Water Policy, which was adopted via Resolution 2009-0011, calls for the development of regional groundwater basin/sub-basin salt/nutrient management plans. Pursuant to the letter from statewide water and wastewater entities dated December 19, 2008, and attached to Resolution 2009-0011, the local water and wastewater entities, together with local salt/nutrient contributing stakeholders, will fund locally driven and controlled, collaborative processes open to all stakeholders that will prepare salt and nutrient management plans for each basin/sub-basin in California, including compliance with CEQA and participation by Central Coast Water Board staff. The policy was added to establish participation in development of a regional groundwater basin/sub-basin salt/nutrient management plan. IV. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS The CWA requires point source dischargers to control the amount of conventional, non- conventional, and toxic pollutants that are discharged into the waters of the United States. The control of pollutants discharged is established through effluent limitations and other requirements in NPDES permits. There are two principal bases for effluent limitations in the Code of Federal Regulations: 40 C.F.R. §122.44(a) requires that permits include applicable technology-based limitations and standards; and 40 C.F.R. §122.44(d) requires that permits include water quality- based effluent limitations to attain and maintain applicable numeric and narrative water quality criteria to protect the beneficial uses of the receiving water. When numeric water quality objectives have not been established, but a discharge has the reasonable potential to cause or contribute to an excursion above a narrative criterion, WQBELs may be established using one or more of three methods described at 40 C.F.R. §122.44 (d) - 1) WQBELs may be established using a calculated water quality criterion derived from a proposed State criterion or an explicit State policy or regulation interpreting its narrative criterion; 2) WQBELs may be established on a case-by-case basis using U.S. EPA criteria guidance published under CWA Section 304 (a); or 3) WQBELs may be established using an indicator parameter for the pollutant of concern. Several specific factors affecting the development of limitations and requirements in this Order are discussed below. A. Discharge Prohibitions 1. Discharge Prohibition III.A (No discharge at a location except as described by this Order): The Order authorizes a single, specific point of discharge to surface waters, and the limitations and conditions established by the Order are based on specific information provided by the Discharger and gained by the Central Coast Water Board through site visits, monitoring reports, and other information. Discharges to surface waters at CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-11 locations not contemplated by this Order or discharges of a character not contemplated by this Order are therefore viewed as inconsistent with CWA § 402’s prohibition against discharges of pollutants except in compliance with the Act’s permit requirements, effluent limitations, and other enumerated provisions. This prohibition has been retained from the previous Order. 2. Discharge Prohibition III.B (No discharge of wastewaters to San Luis Obispo Creek containing bentazon, molinate, or thiobencarb): This prohibition is the same as in the previous permit and is based on the requirements of the Basin Plan. B. Technology-Based Effluent Limitations 1. Scope and Authority Section 301(b) of the CWA and implementing U.S. EPA permit regulations at 40 C.F.R. § 122.44 require that permits include conditions meeting applicable technology-based requirements at a minimum, and any more stringent effluent limitations necessary to meet applicable water quality standards. Where the USEPA has not yet developed technology based standards for a particular industry or a particular pollutant, CWA Section 402 (a) (1) and USEPA regulations at 40 C.F.R. § 125.3 authorize the use of best professional judgment (BPJ) to derive technology-based effluent limitations on a case-by-case basis. When BPJ is used, the permit writer must consider specific factors outlined at 40 C.F.R. § 125.3. Regulations promulgated in 40 C.F.R. § 125.3(a)(1) require technology-based effluent limitations for municipal Dischargers to be placed in NPDES permits based on Secondary Treatment Standards or Equivalent to Secondary Treatment Standards. The Federal Water Pollution Control Act Amendments of 1972 (PL 92-500) established the minimum performance requirements for POTWs [defined in section 304(d)(1)]. Section 301(b)(1)(B) of that Act requires that such treatment works must, as a minimum, meet effluent limitations based on secondary treatment as defined by the U.S. EPA Administrator. Based on this statutory requirement, U.S. EPA developed secondary treatment regulations, which are specified in 40 C.F.R. part 133. These technology-based regulations apply to all municipal wastewater treatment plants and identify the minimum level of effluent quality attainable by secondary treatment in terms of biochemical oxygen demand (BOD5), total suspended solids (TSS), and pH. The discharge authorized by this Order must meet minimum federal technology-based requirements based on Secondary Treatment Standards at 40 C.F.R. part 133. 2. Applicable Technology-Based Effluent Limitations Title 40 C.F.R. § 122.45(f)(1) requires effluent limitations be expressed in terms of mass, with some exceptions, and 40 C.F.R. § 122.45(f)(2) allows pollutants that are limited in terms of mass to additionally be limited in terms of other units of measurement. This Order includes effluent limitations expressed in terms of mass and concentration. In addition, pursuant to the exceptions to mass limitations provided in 40 C.F.R. § 122.45(f)(1), some effluent limitations are not expressed in terms of mass, such as pH and temperature, and when the applicable standards are expressed in terms of concentration and mass limitations are not necessary to protect the beneficial uses of the receiving waters. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-12 a. BOD and TSS. Federal regulations, 40 C.F.R. part 133, establish the minimum weekly and monthly average level of effluent quality attainable by secondary treatment for BOD5 and TSS. Section 301(b) of the CWA and section 122.44(d) require that permits include limitations more stringent than applicable federal technology-based requirements where necessary to achieve applicable water quality standards. This Order contains requirements, expressed as a technology equivalence requirements, more stringent than secondary treatment requirements that are necessary to meet applicable water quality standards. The Central Coast Water Board has determined that tertiary treatment is necessary to protect the beneficial uses of the receiving stream, thus the final effluent limitations for BOD5 and TSS are based on the technical capability of the tertiary process. The secondary and tertiary treatment standards for BOD5 and TSS are indicators of the effectiveness of the treatment processes. The principal design parameter for wastewater treatment plants is the daily BOD5 and TSS loading rates and the corresponding removal rate of the system. In applying 40 C.F.R. part 133 for weekly and monthly average BOD5 and TSS limitations, the application of tertiary treatment processes results in the ability to achieve lower levels for BOD5 and TSS than the secondary standards currently prescribed; the 30-day average BOD5 and TSS limitations are 10 mg/L, the 7-day average BOD5 and TSS limitations are 30 mg/L. These effluent limitations are based on the capability of a tertiary system. In addition to the average weekly and average monthly effluent limitations, daily maximum effluent limitation of 50 mg/L and 75 mg/L for BOD5 and TSS, respectively, are included in the Order to ensure that the treatment works are not organically overloaded and operate in accordance with design capabilities. In addition, 40 C.F.R. § 133.102, in describing the minimum level of effluent quality attainable by secondary treatment, states that the 30-day average percent removal shall not be less than 85 percent. If 85 percent removal of BOD5 and TSS must be achieved by a secondary treatment plant, it must also be achieved by a tertiary (i.e., treatment beyond secondary level) treatment plant. This Order contains a limitation requiring an average of 85 percent removal of BOD5 and TSS over each calendar month. These effluent limitations are carried over from Order No. R3-2002-0043. b. pH. Federal Regulations, 40 C.F.R. part 133, establishes technology-based effluent limitations for pH. The secondary treatment standards require the pH of the effluent to be no lower than 6.0 and no greater than 9.0 standard units. This techonology-based effluent limitation is not as stringent as the WQBELs for pH as discussed in section IV.C of this Fact sheet; therefore, this Order establishes the more stringent WQBELs for pH. c. Flow. According to the Report of Waste Discharge, the Facility is designed to provide a tertiary level of treatment for up to a design flow of 5.1 MGD. Order No. R3-2002-0043 permitted a daily flow of 5.2 MGD. This Order has established a maximum flow based on the design capacity of the Facility, thus, this Order contains an average dry weather daily discharge flow effluent limit of 5.1 MGD. Further, in accordance with 40 C.F.R. § 122.45(b), mass-based effluent limitations are based on the facility design flow of 5.1 MGD. The following table summarizes technology-based effluent limitations established by this Order. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-13 Table F-5. Technology-Based Effluent Limitations [1] In addition to concentration-based limitations and mass-based limitations for BOD5 and TSS, the Discharger is required to meet an 85 percent removal discharge specification. [2] Mass -based effluent limitations are established using the following formula: Mass (lbs/day) = flow rate (MGD) x 8.34 x effluent limitation (mg/L) where: Mass = mass limitation for a pollutant (lbs/day) Effluent limitation = concentration limit for a pollutant (mg/L) Flow rate = discharge flow rate (5.1 MGD) C. Water Quality-Based Effluent Limitations (WQBELs) 1. Scope and Authority NPDES regulations at 40 C.F.R. 122.44 (d) require that permits include limitations more stringent than applicable federal technology-based requirements where necessary to achieve applicable water quality standards, including numeric and narrative objectives within a standard. The process for determining “reasonable potential” and calculating WQBELs, when necessary, is intended to protect the designated uses of receiving waters as specified in the Basin Plan, and achieve applicable WQOs and criteria that are contained in the Basin Plan and in other applicable State and federal rules, plans, and policies, including applicable water quality criteria from the CTR and the NTR. Where reasonable potential has been established for a pollutant, but there is no num eric criterion or objective for the pollutant, WQBELs must be established in accordance with the requirements of 40 C.F.R. 122.44(d)(1)(vi), using (1) USEPA criteria guidance under CWA section 304(a), supplemented where necessary by other relevant informat ion; (2) an indicator parameter for the pollutant of concern; or (3) a calculated numeric water quality criterion, such as a proposed State criterion or policy interpreting the State’s narrative criterion, supplemented with other relevant information. 2. Applicable Beneficial Uses and Water Quality Criteria and Objectives Beneficial uses described by the Basin Plan for San Luis Obispo Creek are presented in section III.C.1 of this Fact Sheet. Water quality criteria applicable to this receiving water are established by the CTR, the NTR, and by the Basin Plan. Reasonable potential for pollutants with applicable water quality criteria was evaluated for Discharge Point No. 001. Parameter Units Effluent Limitations Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Flow MGD -- -- 5.1 -- -- Biochemical Oxygen Demand (BOD5) (5-day @ 20 Deg. C) [1] mg/L 10 30 50 -- -- lbs/day [2] 425 1,275 2,125 -- -- Total Suspended Solids [1] mg/L 10 30 75 -- -- lbs/day [2] 425 1,275 3,188 -- -- pH standard units -- -- -- 6.0 9.0 CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-14 3. Determining the Need for WQBELs NPDES regulations at 40 C.F.R. §122.44(d) require effluent limitations to control all pollutants which are or may be discharged at a level which will cause, have the reasonable potential to cause, or contribute to an excursion above any State water quality standard. The SIP, statewide policy that became effective on May 22, 2000, establishes procedures to implement water quality criteria from the NTR and CTR and for priority, toxic pollutant objectives established in the Basin Plan. The implementation procedures of the SIP include methods to determine reasonable potential (for pollutants to cause or contribute to excursions above State water quality standards) and to establish numeric effluent limitations, if necessary, for those pollutants which show reasonable potential. The SIP Section 1.3 requires the Regional Water Board to use all available valid, relevant, and representative receiving water and effluent data and information to conduct a reasonable potential analysis. The Central Coast Water Board analyzed the Discharger’s data for priority pollutants and the nature of the discharge to determine if the discharge has Reasonable Potential. The RPA is based on effluent data retrieved from CIWQS and ICIS, as well as effluent data received from the Discharger for the period of January 2008 to October 2012. Some freshwater water quality criteria for metals are hardness dependent; i.e., as hardness decreases, the toxicity of certain metals increases and the applicable water quality criteria become correspondingly more stringent. The Discharger has not specifically collected hardness data for the receiving water. However, the Central Coast Water Board’s Central Coast Ambient Monitoring Program has a nearby monitoring stations on San Luis Obispo Creek. The median hardness values from those stations are 400 and 330 mg/L as CaCO3, respectively upgradient and downgradient from the discharge location. The Water Board used 330 mg/L as CaCO3 as a conservative estimate of the receiving water hardness to determine hardness-based criteria. To conduct the reasonable potential analysis, the Central Coast Water Board identified the maximum observed effluent (MEC) from effluent data provided by the Discharger and compared these data to the most stringent applicable water quality criterion (C) for each pollutant from the NTR, CTR, and the Basin Plan. The Discharger did not collect background data (B) from the receiving water. Section 1.3 of the SIP establishes three triggers for a finding of reasonable potential. Trigger 1. If the MEC is greater than C, there is reasonable potential, and an effluent limitation is required. Trigger 2. If B is greater than C, and the pollutant is detected in effluent (MEC > ND), there is reasonable potential, and an effluent limitation is required. In this case, the Discharger did not collect background (B) data, so reasonable potential cannot be found by Trigger 2. Trigger 3. After reviewing other available and relevant information, a permit writer may decide that a WQBEL is required. Such additional information may include, but is not limited to: the facility type, the discharge type, solids loading analyses, lack of dilution, history of compliance problems, potential toxic impact of the discharge, fish tissue residue data, water quality and beneficial uses of the receiving water, CWA section 303(d) listing for the pollutant, and the presence of endangered or threatened species or their critical habitat. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-15 The following table summarizes the RPA for each priority pollutant, toxic pollutant, or Title 22 pollutant that was measured in effluent collected for the period January 2008 to December 2012. Table F-6. Summary of RPA Results CTR# Priority Pollutant MEC or Minimum DL (1)(2) (µg/L) Governing WQO/WQC (µg/L) Maximum Background or Minimum (1)(2) DL (µg/L) RPA Results (3) 1 Antimony <1 6 --- No 2 Arsenic <2 10 --- No 3 Beryllium <0.2 4 --- No 4 Cadmium <0.2 5.0 --- No 5a Chromium (III) <1 550 --- No 5b Chromium (VI) <10 11 --- No 6 Copper 19 25.9 --- No 7 Lead 5 14.5 --- No 8 Mercury <0.02 0.05 --- No 9 Nickel 10 100 --- No 10 Selenium 4.1 5 --- No 11 Silver <1 31.6 --- No 12 Thallium <0.2 1.7 --- No 13 Zinc 50 200 --- No 14 Cyanide 4.0 5.2 --- No 15 Asbestos (Fibers/L) <0.3 7,000,000 --- No 16 2,3,7,8-TCDD <6.8x10-7 1.3x10-8 --- No 17 Acrolein <0.05 320 --- No 18 Acrylonitrile <0.05 0.059 --- No 19 Benzene <0.05 1 --- No 20 Bromoform 1.9 4.3 --- No 21 Carbon Tetrachloride <0.05 0.25 --- No 22 Chlorobenzene <0.05 70 --- No 23 Chlorodibromomethane 20 0.401 --- Yes 24 Chloroethane <0.05 No Criteria --- No 25 2-Chloroethylvinyl ether <0.05 No Criteria --- No 26 Chloroform 85.9 No Criteria --- No 27 Dichlorobromomethane 17.6 0.56 --- Yes 28 1,1-Dichloroethane <0.05 5 --- No 29 1,2-Dichloroethane <0.05 0.38 --- No 30 1,1-Dichloroethylene <0.05 0.057 --- No 31 1,2-Dichloropropane <0.05 0.52 --- No 32 1,3-Dichloropropylene <0.05 0.5 --- No 33 Ethylbenzene <0.05 300 --- No 34 Methyl Bromide <0.05 48 --- No 35 Methyl Chloride 0.9 No Criteria --- Ud 36 Methylene Chloride <0.05 4.7 --- No 37 1,1,2,2-Tetrachloroethane <0.05 0.17 --- No 38 Tetrachloroethylene <0.05 0.8 --- No 39 Toluene 1.0 150 --- No 40 1,2-Trans-Dichloroethylene <0.05 10 --- No 41 1,1,1-Trichloroethane <0.05 200 --- No 42 1,1,2-Trichloroethane <0.05 0.6 --- No 43 Trichloroethylene <0.05 2.7 --- No CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-16 CTR# Priority Pollutant MEC or Minimum DL (1)(2) (µg/L) Governing WQO/WQC (µg/L) Maximum Background or Minimum (1)(2) DL (µg/L) RPA Results (3) 44 Vinyl Chloride <0.05 0.5 --- No 45 2-Chlorophenol <0.05 120 --- No 46 2,4-Dichlorophenol <0.05 93 --- No 47 2,4-Dimethylphenol <0.05 540 --- No 48 2-Methyl- 4,6-Dinitrophenol <0.05 13.4 --- No 49 2,4-Dinitrophenol <0.05 70 --- No 50 2-Nitrophenol <0.05 No Criteria --- Ud 51 4-Nitrophenol <0.05 No Criteria --- Ud 52 3-Methyl 4-Chlorophenol <0.05 No Criteria --- Ud 53 Pentachlorophenol 1.2 0.28 --- Yes 54 Phenol <0.05 21,000 --- No 55 2,4,6-Trichlorophenol <0.05 2.1 --- No 56 Acenaphthene <0.05 1,200 --- No 57 Acenaphthylene <0.05 No Criteria --- Ud 58 Anthracene <0.05 9,600 --- No 59 Benzidine <0.05 0.00012 --- No 60 Benzo(a)Anthracene <0.05 0.0044 --- No 61 Benzo(a)Pyrene <0.05 0.0044 --- No 62 Benzo(b)Fluoranthene <0.05 0.0044 --- No 63 Benzo(ghi)Perylene <0.05 No Criteria --- Ud 64 Benzo(k)Fluoranthene <0.05 0.0044 --- No 65 Bis(2-Chloroethoxy)Methane <0.05 No Criteria --- Ud 66 Bis(2-Chloroethyl)Ether <0.05 0.031 --- No 67 Bis(2-Chloroisopropyl)Ether <0.05 1400 --- No 68 Bis(2-Ethylhexyl)Phthalate <0.05 1.8 --- No 69 4-Bromophenyl Phenyl Ether <0.05 No Criteria --- Ud 70 Butylbenzyl Phthalate <0.05 3000 --- No 71 2-Chloronaphthalene <0.05 1700 --- No 72 4-Chlorophenyl Phenyl Ether <0.05 No Criteria --- Ud 73 Chrysene <0.05 0.0044 --- No 74 Dibenzo(a,h)Anthracene <0.05 0.0044 --- No 75 1,2-Dichlorobenzene <0.05 600 --- No 76 1,3-Dichlorobenzene <0.05 400 --- No 77 1,4-Dichlorobenzene <0.05 5 --- No 78 3,3 Dichlorobenzidine <0.05 0.04 --- No 79 Diethyl Phthalate <0.05 23,000 --- No 80 Dimethyl Phthalate <0.05 313,000 --- No 81 Di-n-Butyl Phthalate <0.05 2,700 --- No 82 2,4-Dinitrotoluene <0.05 0.11 --- No 83 2,6-Dinitrotoluene <0.05 No Criteria --- Ud 84 Di-n-Octyl Phthalate <0.05 No Criteria --- Ud 85 1,2-Diphenylhydrazine <0.05 0.04 --- No 86 Fluoranthene <0.05 300 --- No 87 Fluorene <0.05 1,300 --- No 88 Hexachlorobenzene <0.05 0.00075 --- No 89 Hexachlorobutadiene <0.05 0.44 --- No 90 Hexachlorocyclopentadiene <0.05 50 --- No 91 Hexachloroethane <0.05 1.9 --- No 92 Indeno(1,2,3-cd)Pyrene <0.05 0.0044 --- No CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-17 CTR# Priority Pollutant MEC or Minimum DL (1)(2) (µg/L) Governing WQO/WQC (µg/L) Maximum Background or Minimum (1)(2) DL (µg/L) RPA Results (3) 93 Isophorone <0.05 8.4 --- No 94 Naphthalene <0.05 No Criteria --- Ud 95 Nitrobenzene <0.05 17 --- No 96 N-Nitrosodimethylamine 12 0.00069 --- Yes 97 N-Nitrosodi-n-Propylamine <0.05 0.005 --- No 98 N-Nitrosodiphenylamine <0.05 5 --- No 99 Phenanthrene <0.05 No Criteria --- Ud 100 Pyrene <0.05 960 --- No 101 1,2,4-Trichlorobenzene <0.05 5 --- No 102 Aldrin <0.05 0.00013 --- No 103 alpha-BHC <0.05 0.0039 --- No 104 beta-BHC <0.05 0.014 --- No 105 gamma-BHC <0.05 0.019 --- No 106 delta-BHC <0.05 No Criteria --- Ud 107 Chlordane <0.05 0.00057 --- No 108 4,4'-DDT <0.05 0.00059 --- No 109 4,4'-DDE <0.05 0.00059 --- No 110 4,4'-DDD <0.05 0.00083 --- No 111 Dieldrin <0.05 0.00014 --- No 112 alpha-Endosulfan <0.05 0.056 --- No 113 beta-Endolsulfan <0.05 0.056 --- No 114 Endosulfan Sulfate <0.05 110 --- No 115 Endrin <0.05 0.036 --- No 116 Endrin Aldehyde <0.05 0.76 --- No 117 Heptachlor <0.05 0.00021 --- No 118 Heptachlor Epoxide <0.05 0.0001 --- No 119- 125 PCBs sum <0.05 0.00017 --- No 126 Toxaphene <0.05 0.0002 --- No Drinking Water Quality Objectives Aluminum 40 1,000 --- No Barium 36.2 1,000 --- No Fluoride 900 1,000 --- No Nitrate (as NO3) (mg/L) (4) 260 45 --- Yes Nitrate+Nitrite (sum as N) (mg/L) 58.7 10 --- Yes Nitrite (as N) (mg/L) <0.1 1 --- No Methyl-tert-butyl-ether <1 13 --- No Styrene <0.5 100 --- No Alachlor <0.2 2 --- No Atrazine <0.5 1 --- No Bentazon <2 18 --- No Carbofuran <5 18 --- No 2,4-D <2 70 --- No Dalapon <10 200 --- No Dibromochloropropane --- 0.2 --- No Di (2-ethylhexyl) adipate <5 400 --- No Dinoseb <1 7 --- No Diquat <2 20 --- No CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-18 CTR# Priority Pollutant MEC or Minimum DL (1)(2) (µg/L) Governing WQO/WQC (µg/L) Maximum Background or Minimum (1)(2) DL (µg/L) RPA Results (3) Endothall <40 100 --- No Ethylene Dibromide --- 0.05 --- Ud Glyphosate <20 700 --- No Methoxychlor <0.1 30 --- No Molinate <2 20 --- No Oxamyl <5 50 --- No Picloram <1 500 --- No Simazine <1 4 --- No Thiobencarb <1 70 --- No 2, 4, 5-TP (Silvex) <1 50 --- No Trichlorofluoromethane <1 150 --- No 1,1,2-Trichloro-1,2,2- Trifluoroethane <0.5 1,200 --- No Xylenes 0.5 1,750 --- No Tributyltin --- No Criteria --- Ud Total PAHs --- No Criteria --- Ud Strontium-90 (pCi/L) --- 8 --- Ud Tritium (pCi/L) --- 20,000 --- Ud Ra-226/228 (pCi/L) --- 5 --- Ud Gross Alpha (pCi/L) --- 15 --- Ud Gross Beta (pCi/L) --- No Criteria --- Ud U (pCi/L) --- 20 --- Ud Board 3 Basin Plan WQOs for Agricultural Water Use Manganese 22.6 200 --- No Cobalt 0.5 50 --- No Iron 110 5000 --- No Lithium 17 2500 --- No Molybdenum --- 10 --- Ud Vanadium <1 100 --- No Boron 300 750 --- No Footnotes for Table F-5: (1) The MEC or maximum background concentration is the actual detected concentration. Where detection values were available and the pollutant was not detected, the detection value was provided with a “<” before it. Where the pollutant was non-detect and a detection value was not available, “ND” was entered. (2) Cells marked with “---“ indicate that no effluent data or background data are available for that constituent. (3) RPA Results = Yes, if MEC => WQO/WQC, or if B > WQO/WQC and constituent is detected; = No, if MEC and B are < WQO/WQC or all effluent data are undetected; = Undetermined (Ud), if no criteria have been promulgated or no effluent data available; (4) Converted from nitrate (as N). Reasonable potential has been determined for chlorodibromomethane, dichlorobromomethane, pentachlorophenol, N-nitrosdimethylamine, nitrate, and nitrate+nitrite. WQBELs have been established for chlorodibromomethane, dichlorobromomethane, and N-nitrosdimethylamine based on the procedures identified within Section 1.4 of the SIP, as discussed in section IV.C.4 below. Pentachlorophenol did not ultimately have WQBELs established due to data quality uncertainties. The Discharger provided comment on initial RPA results and noted that they erroneously reported the single detection of pentachlorophenol in October 2012 as CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-19 1.2 µg/L. The Discharger should have reported the results as detected, not quantified (DNQ). According to Section 2.4 of the SIP, when the analytical result is above the method detection limit but below the minimum level, the result shall be reported as DNQ and the estimated concentration reported. If pentachlorophenol had been reported as DNQ in this instance, the RPA would have yielded a “no reasonable potential” conclusion and an effluent limit would not be established. However, increased monitoring for pentachlorophenol has been added to the proposed Order to address the data uncertainty presented by the DNQ result. If future monitoring data indicate a reasonable potential to exceed the water quality objective for pentachlorophenol, an effluent limitation may be established. The Central Coast Water Board developed a WQBEL for nitrate-nitrogen, which has an available wasteload allocation under a Total Maximum Daily Loads (TMDL) in Resolution No. R3-2005-0106 on September 9, 2005. The effluent limitation for this pollutant was established regardless of whether there is reasonable potential for the pollutants to be present in the discharge at levels that would cause or contribute to a violation of water quality standards. The Central Coast Water Board developed a W QBEL for this pollutant pursuant to 40 C.F.R. § 122.44(d)(1)(vii), which does not require or contemplate a reasonable potential analysis. Similarly, the SIP at Section 1.3 recognizes that reasonable potential analysis is not appropriate if a TMDL has been developed. This Order contains a WQBEL for nitrate-nitrogen, established based on the available wasteload allocation of 10 mg/L-N for the Facility contained in Resolution No. R3-2005- 0106. As required by 40 C.F.R. § 122.44(d)(1)(vii), the Central Coast Water Board shall ensure there is a WQBEL for nitrate-nitrogen in the WDRs that is consistent with the assumptions and requirements of the available wasteload allocation. Based on the water quality monitoring done at the time of the TMDL adoption, which set the wasteload allocation at the level necessary to attain water quality standards, the Central Coast Water Board has determined that the WQBEL is consistent with the assumptions of the TMDL. Similarly, compliance with the effluent limitation will satisfy the requirements of the TMDL. A separate WQBEL has not been established for nitrate+nitrite. The Discharger has provided a consistent data set indicating nitrite is not detected in its effluent (and this is consistent with municipal wastewater secondary treatment facilities in general), and therefore establishing a WQBEL for nitrate+nitrite would be duplicative of the nitrate effluent limit discussed above. The Central Coast Water Board has determined the TMDL-based effluent limit is sufficiently protective of the water quality objectives for nitrate+nitrite. 4. WQBEL Calculations Final WQBELs for chlorodibromomethane, dichlorobromomethane, and N- nitrosdimethylamine have been determined using the methods described in Section 1.4 of the SIP. Step 1: For each water quality criterion/objective, an effluent concentration allowance (ECA) is calculated from the following equation to account for dilution and background levels of each pollutant. ECA = C + D (C - B), where C = the applicable water quality criterion (adjusted for receiving water hardness and expressed as total recoverable metal, if necessary) CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-20 D = the dilution credit (here D = 0, as the Central Coast Water Board has no information with which to justify credit for dilution) B = the background concentration Step 2: For each ECA based on an aquatic life criterion, the long-term average discharge condition (LTA) is determined by multiplying the ECA times a factor (multiplier), which adjusts the ECA to account for effluent variability. The multiplier varies depending on the coefficient of variation (CV) of the data set and whether it is an acute or chronic criterion/objective. Table 1 of the SIP provides pre-calculated values for the multipliers based on the value of the CV. When the data set contains less than 10 sample results, or 80 percent or more of the data are reported as non- detect (ND), the CV is set equal to 0.6. Derivation of the multipliers is presented in Section 1.4 of the SIP. Step 3: WQBELs, including an average monthly effluent limitation (AMEL) and a maximum daily effluent limitation (MDEL) are calculated using the most limiting (the lowest) LTA. The LTA is multiplied times a factor that accounts for averaging periods and exceedance frequencies of the effluent limitations, and for the AMEL, the effluent monitoring frequency. Here, the sampling frequency is set equal to 4 (n = 4). The 99th percentile occurrence probability was used to determine the MDEL multiplier and a 95th percentile occurrence probability was used to determine the AMEL multiplier. Table 2 of the SIP presents the MDEL and AMEL multipliers as a function of the CV. When the data set contains less than 10 sample results, or when 80 percent or more of the data set is reported as non-detect (ND), the CV is set equal to 0.6. Otherwise, the CV is calculated as the standard deviation divided by the mean. Step 4: When the most stringent water quality criterion is a human health criterion (i.e., chlorodibromomethane, dichlorobromomethane, and N-nitrosdimethylamine), the AMEL is set equal to the ECA, and the MDEL is calculated by multiplying the ECA times the ratio of the MDEL multiplier to the AMEL multiplier. Final WQBELs for chlorodibromomethane, dichlorobromomethane, and N-nitrosdimethylamine are determined as follows. Table F-9. Calculation of Human Health WQBELs Pollutant ECA MDEL/AMEL Multiplier MDEL (µg/L) AMEL (µg/L) Chlorodibromomethane 0.401 4.96/1.96 = 2.53 1.0 0.40 Dichlorobromomethane 0.56 2.43/1.39 = 1.74 1.0 0.56 N-nitrosdimethylamine 0.00069 3.11/1.55 = 2.01 0.0014 0.00069 5. Whole Effluent Toxicity (WET) WET limitations protect receiving water quality from the aggregated toxic effect of a mixture of pollutants in effluent. WET tests measure the degree of response of exposed aquatic test organisms to an effluent. The WET approach allows for protection of the narrative “no toxics in toxic amounts” criterion while implementing numeric criteria for toxicity. There are two types of WET tests - acute and chronic. An acute toxicity test is conducted over a short time period and measures mortality. A chronic toxicity test is conducted over a longer period of time and may measure mortality, reproduction, and growth. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-21 The Basin Plan requires that all waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Survival of aquatic organisms in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same water body in areas unaffected by the waste discharge or for another control water. The previous Order included narrative effluent limitations for toxicity to ensure compliance with the Basin Plan narrative objective. The effluent limitation has been retained from the previous Order. Numeric chronic WET effluent limitations have not been included in this Order. The SIP contains implementation gaps regarding the appropriate form and implementation of chronic toxicity limits. This has resulted in the petitioning of a NPDES permit in the Los Angeles Region 1 that contained numeric chronic toxicity effluent limitations. To address the petition, the State Water Board adopted WQO 2003-012 directing its staff to revise the toxicity control provisions in the SIP. The State Water Board states the following in WQO 2003-012, “In reviewing this petition and receiving comments from numerous interested persons on the propriety of including numeric effluent limitations for chronic toxicity in NPDES permits for publicly-owned treatment works that discharge to inland waters, we have determined that this issue should be considered in a regulatory setting, in order to allow for full public discussion and deliberation. We intend to modify the SIP to specifically address the issue. We anticipate that review will occur within the next year. We therefore decline to make a determination here regarding the propriety of the final numeric effluent limitations for chronic toxicity contained in these permits.” The process to revise the SIP is currently underway. Proposed changes include clarifying the appropriate form of effluent toxicity limits in NPDES permits and general expansion and standardization of toxicity control implementation related to the NPDES permitting process. Since the toxicity control provisions in the SIP are currently under revision, it is inappropriate to carry over numeric effluent limitations for chronic toxicity. Therefore, this Order establishes a narrative toxicity effluent limitation and a numeric toxicity triggers consistent with the previous chronic toxicity effluent limitation which will require that the Discharger meet best management practices for compliance with the Basin Plan’s narrative toxicity objective, as allowed under 40 C.F.R. § 122.44(k). To ensure compliance with the Basin Plan’s narrative toxicity objective, the Discharger is required to conduct acute and chronic WET testing, as specified in the Monitoring and Reporting Program (Attachment E, section V). Furthermore, the Special Provision contained at VI.C.2.a of this Order requires the Discharger to investigate the causes of, and identify and implement corrective actions to reduce or eliminate effluent toxicity. If the discharge demonstrates toxicity, the Discharger is required to initiate a Toxicity Reduction Evaluation (TRE) in accordance with an approved TRE workplan. The numeric chronic toxicity monitoring trigger is not an effluent limitation; it is the toxicity threshold at which the Discharger is required to perform accelerated chronic toxicity monitoring, as well as, the threshold to initiate a TRE if effluent toxicity has been demonstrated. 1 In the Matter of the Review of Own Motion of Waste Discharge Requirements Orders R4-2002-0121 [NPDES No. CA0054011] and R4-2002-0123 [NPDES No. CA0055119] and Time Schedule Orders R4- 2002- 0122 and R4-2002-0124 for Los Coyotes and Long Beach Wastewater Reclamation Plants Issued by the California Regional Water Quality Control Board, Los Angeles Region SWRCB/OCC FILES A-1496 and 1496(a). CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-22 6. Basin Plan a. Coliform. The beneficial uses of the receiving surface water include municipal and domestic supply and water contact recreation. The California Department of Public Health (DPH) has developed reclamation criteria, CCR, Division 4, Chapter 3 (Title 22), for the reuse of wastewater. Title 22 requires that for spray irrigation of food crops, parks, playgrounds, schoolyards, and other areas of similar public access, wastewater be adequately disinfected, oxidized, coagulated, clarified, and filtered, and that the effluent total coliform levels not exceed 2.2 MPN/100 mL as a 7-day median; 23 MPN/100 mL, not to be exceeded more than once in a 30-day period; and 240 MPN/100 mL, at any time. Title 22 also requires that recycled water used as a source of water supply for non- restricted recreational impoundments be disinfected tertiary recycled water that has been subjected to conventional treatment. A non-restricted recreational impoundment is defined as “…an impoundment of recycled water, in which no limitations are imposed on body-contact water recreational activities.” Title 22 is not directly applicable to surface waters; however, the Central Coast Water Board finds that it is appropriate to apply an equivalent level of treatment to that required by DPH’s reclamation criteria because the receiving water is used for irrigation of agricultural land and for contact recreation purposes. The stringent disinfection criteria of Title 22 are appropriate since the undiluted effluent may be used for the irrigation of food crops and/or for body-contact water recreation. Coliform organisms are intended as an indicator of the effectiveness of the entire treatment train and the effectiveness of removing other pathogens. The previous Order includes effluent limitations for fecal coliform organisms of 2.2 MPN/100 mL as a 7-day median (in contrast to the Title 22 requirement based on the more conservative total coliform organisms). The consideration for this deviation was based on studies at the Facility during rapid changes in influent wastewater strength and flowrate (e.g., when California Polytechnic State University (Cal Poly) begins sessions or when power supply is interrupted). Those studies showed that, during these events, the Facility can temporarily experience an increased growth of non-pathogenic Klebsiella species of coliform bacterium within the cooling towers. That growth would result in total coliform detections with low-to-no fecal coliform component. In other words, the Facility still maintained the desired effectiveness at removing pathogenic coliform species. According to 2013 monitoring data, these events occurred two times; once in June during a power outage and once in September when Cal Poly began sessions. Fecal coliforms in both instances were below a 2.2 MPN/100 mL 7-sample median. These infrequent, non-pathogenic total coliform exceedances of a 2.2 MPN/100 mL median do not represent a failure of the disinfection system. Based on these studies, the existing effluent limitations have been retained and are protective of the beneficial uses for San Luis Obispo Creek. These effluent limits are generally consistent with other inland surface water discharge permits within the region. b. Dissolved Oxygen. In order to protect the beneficial uses of San Luis Obispo Creek, Order No. R3-2002-0043 established an effluent limitation for dissolved oxygen, prohibiting the discharge from containing a dissolved oxygen concentration of less than 4.0 mg/L or so low that it adversely affects beneficial uses. Due to federal and State anti-backsliding regulations, dissolved oxygen remains a pollutant CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-23 of concern for this discharge and the effluent limitation from the previous Order is carried over. c. Nitrate-Nitrogen. San Luis Obispo Creek is included on the 303(d) List as impaired for nutrients. Central Coast Water Board Resolution R3-2005-0106 establishes TMDLs for nitrate-nitrogen for discharges to San Luis Obispo Creek. The TMDL specifies a wasteload allocation for the City of San Luis Obispo Water Reclamation Facility effluent of 9,740 lbs NO3 (as N)/month. This wasteload allocation will be accomplished by establishing a nitrate-nitrogen effluent monthly average limit of 10 mg/L. Further, the implementation section of the TMDL specifies that the Central Coast Water Board will incorporate an effluent limit for nitrate-nitrogen in the City of San Luis Obispo’s NPDES permit for the Water Reclamation Facility, consistent with the allocations described in the wasteload allocations section at the first permit renewal following TMDL approval by the Central Coast Water Board. Thus, this Order implements the wasteload allocation as specified in Central Coast Water Board Resolution No. R3-2005-0106. Based on 40 C.F.R. § 122.44 (d.1.vii.B.) effluent limitations developed to protect a narrative water quality criterion, a numeric water quality criterion, or both, are consistent with the assumptions and requirements of any available wasteload allocation for the discharge prepared by the State and approved by EPA pursuant to 40 C.F.R. § 130.7. pH. Federal regulations, 40 CFR 133, establish technology-based effluent limitations for pH. The secondary treatment standards require the pH of the effluent to be no lower than 6.0 and no greater than 9.0 standard units. However, the Basin Plan establishes a WQO for pH of between 6.5 to 8.3 standard units for the protection of receiving waters with the beneficial use of Municipal and Domestic Supply (MUN), Agricultural Supply (AGR), and Water Recreation (REC1 and REC2). The Basin Plan establishes a WQO for pH between 7.0 to 8.5 standard units for the beneficial use of Freshwater Habitat (COLD and WARM) and Fish Spawning (SPWN). The previous Order established an effluent limitation of 6.5 to 8.3. However, since San Luis Obispo Creek has MUN, AGR, REC1, REC2, COLD, WARM, and SPWN beneficial uses, a pH effluent limitation of 7.0 to 8.3 may be appropriate in order to protect all beneficial uses. The Discharger shall complete an Effluent pH Evaluation by February 1, 2016, to assess opportunities for effluent pH adjustments consistent with more stringent Basin Plan water quality objectives for receiving water (i.e., 7.0-8.3 standard units), impact on receiving water and environment, cost to pH adjust, and expected frequency and duration that effluent pH would drop below 7.0 s.u. under current operations. Central Coast Water Board staff will review the data to consider whether a more stringent pH effluent limit would indeed be more protective of water quality objectives or if existing pH effluent limits are adequately protective of receiving water quality objectives. d. Oil and Grease. The Basin Plan establishes a narrative effluent limitation for oil and grease, which states, “Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses.” The previous Order contained an AMEL and MDEL of 5.0 mg/L and 10 mg/L, and corresponding mass-based effluent limitations, respectively. These CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-24 effluent limitations are typical of similar facilities that discharge secondary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the concentration-based effluent limitations from the previous Order. Mass-based limitations have been removed from the proposed Order. This change does not represent backsliding as the Order contains a flow limitation, which when combined with a concentration-based effluent limitation, provides equivalent protection for this water quality objective. e. Settleable Solids. The Basin Plan establishes a narrative effluent limitation for settleable solids, which states, “Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses.” The previous Order contained an average monthly effluent limitation (AMEL) of 0.1 mL/L. This effluent limitation is typical of similar facilities that discharge secondary treated wastewater and is necessary to protect the narrative water quality objective. Therefore, this Order retains the effluent limitation for settleable solids from the previous Order. D. Final Effluent Limitation Considerations 1. Anti-Backsliding Requirements Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. section 122.44(l) prohibit backsliding in NPDES permits. These anti-backsliding provisions require effluent limitations in a reissued permit to be as stringent as those in the previous permit, with some exceptions where limitations may be relaxed. The effluent limitations in this Order are at least as stringent as the effluent limitations in the previous Order, with the exception of effluent limitations for selenium, cyanide, bromoform, aluminum, barium, fluoride, cis-1,2-Dichloroethylene, methyl-tertiary-butyl-ether, styrene, trichlorofluoromethane, 1,1,2-Trichloro-1,2,2-Trifluoroethane, xylenes, alachlor, atrazine, bentazon, carbofuran, 2,4-D, dalapon, dibromochloropropane, di(2-ethylhexyl)adipate, di(2-ethylhexyl)phthalate, dinoseb, diquat, endothall, ethylene dibromide, glyphosate, methoxychlor, molinate, oxamyl, picloram, simazine, thiobencarb, and 2,4,5-TP (Silvex). The existing Order (R3-2002-0043) final effluent limitations for selenium, cyanide, bromoform, aluminum, barium, fluoride, cis-1,2-Dichloroethylene, methyl-tertiary-butyl- ether, styrene, trichlorofluoromethane, 1,1,2-Trichloro-1,2,2-Trifluoroethane, xylenes, alachlor, atrazine, bentazon, carbofuran, 2,4-D, dalapon, dibromochloropropane, di(2- ethylhexyl)adipate, di(2-ethylhexyl)phthalate, dinoseb, diquat, endothall, ethylene dibromide, glyphosate, methoxychlor, molinate, oxamyl, picloram, simazine, thiobencarb, and 2,4,5-TP (Silvex). Effluent limitations for selenium, cyanide, bromoform, aluminum, barium, fluoride, cis-1,2-Dichloroethylene, methyl-tertiary-butyl-ether, styrene, trichlorofluoromethane, 1,1,2-Trichloro-1,2,2-Trifluoroethane, xylenes, alachlor, atrazine, bentazon, carbofuran, 2,4-D, dalapon, dibromochloropropane, di(2-ethylhexyl)adipate, di(2-ethylhexyl)phthalate, dinoseb, diquat, endothall, ethylene dibromide, glyphosate, methoxychlor, molinate, oxamyl, picloram, simazine, thiobencarb, and 2,4,5-TP (Silvex) are discontinued in this Order and chlorodibromomethane and dichlorobromomethane effluent limitations are revised in this Order based on the consideration of new information (i.e., current discharge monitoring data and reasonable potential analysis). This relaxation of effluent limitations is consistent with the anti-backsliding requirements of the CWA and federal regulations. 2. Antidegradation Policies CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-25 Provisions of the Order are consistent with applicable anti-degradation policy expressed by NPDES regulations at 40 C.F.R. § 131.12 and by State Water Board Resolution 68- 16. This Order does not authorize increases in discharge rates or pollutant loadings, and its limitations and conditions otherwise assure maintenance of the existing quality of receiving waters. 3. Stringency of Requirements for Individual Pollutants This Order contains both technology-based and water quality-based effluent limitations for individual pollutants. The technology-based effluent limitations consist of restrictions on flow, BOD, and TSS. Restrictions on flow, BOD, and TSS are discussed in section VI.B of the Fact Sheet. This Order’s technology-based pollutant restrictions implement the minimum, applicable federal technology-based requirements. In addition, this Order contains effluent limitations more stringent than the minimum, federal technology-based requirements that are necessary to meet water quality standards. These limitations are not more stringent than required by the CWA. Water quality-based effluent limitations have been derived to implement water quality objectives that protect beneficial uses. Both the beneficial uses and the water quality objectives have been approved pursuant to federal law and are the applicable federal water quality standards. To the extent that toxic pollutant water quality-based effluent limitations were derived from the CTR, the CTR is the applicable standard pursuant to 40 C.F.R. § 131.38. The procedures for calculating the individual water quality-based effluent limitations for priority pollutants are based on the CTR implemented by the SIP, which was approved by U.S. EPA on May 18, 2000. All beneficial uses and water quality objectives contained in the Basin Plan were approved under state law and submitted to and approved by U.S. EPA prior to May 30, 2000. Any water quality objectives and beneficial uses submitted to U.S. EPA prior to May 30, 2000, but not approved by U.S. EPA before that date, are nonetheless “applicable water quality standards for purposes of the CWA” pursuant to 40 C.F.R. § 131.21(c)(1). Collectively, this Order’s restrictions on individual pollutants are no more stringent than required to implement the requirements of the CWA. 4. Summary of Final Effluent Limitations – Discharge Point 001 Final effluent limitations were determined by comparing the technology-based effluent limitations (including the effluent limitations established in Order No. R3-2002-0043) and the WQBELs and applying the most stringent limitations for each individual parameter. Effluent limitations for BOD5 and TSS are technology based and are carried over from Order No. R3-2002-0043. Effluent limitations for chlorodibromomethane, dichlorobromomethane, N-Nitrosodimethylamine, dissolved oxygen, coliform, nitrate- nitrogen, total residual chlorine, settleable solids, oil and grease, and pH are based on applicable water quality criteria. Effluent limitations for selenium, cyanide, bromoform, aluminum, barium, fluoride, cis-1,2-Dichloroethylene, methyl-tertiary-butyl-ether, styrene, trichlorofluoromethane, 1,1,2-Trichloro-1,2,2-Trifluoroethane, xylenes, alachlor, atrazine, bentazon, carbofuran, 2,4-D, dalapon, dibromochloropropane, di(2-ethylhexyl)adipate, di(2-ethylhexyl)phthalate, dinoseb, diquat, endothall, ethylene dibromide, glyphosate, methoxychlor, molinate, oxamyl, picloram, simazine, thiobencarb, and 2,4,5-TP (Silvex) are discontinued in this Order because the discharge did not demonstrate reasonable potential to cause or contribute to an exceedance of a water quality standard. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-26 The effluent limitation established for flow is based on the design flow capacity of the Facility. Mass-based effluent limitations, as required, were calculated based upon the permitted design daily discharge flow of 5.1 MGD. a. The Discharger shall maintain compliance with the following effluent limitations at Discharge Point 001, with compliance measured at Monitoring Location EFF-001 as described in the attached Monitoring and Reporting Program (MRP) (Attachment E). Table F-10. Summary of Final Effluent Limitations Parameter Units Effluent Limitations Basis[1] Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum CONVENTIONALS Biochemical Oxygen Demand (BOD5) (5-day @ 20 Deg. C) [2] mg/L 10 30 50 -- -- C.F.R. lbs/day [3] 425 1,275 2,125 -- -- Oil and Grease mg/L 5 -- 10 -- -- PO pH s.u. -- -- -- 6.5 8.3 BP Total Suspended Solids [2] mg/L 10 30 75 -- -- C.F.R. lbs/day [3] 425 1,275 2,125 -- -- Chlorodibromomethane µg/L 0.40 -- 1.0 -- -- CTR Dichlorobromomethane µg/L 0.56 -- 1.0 -- -- CTR N- Nitrosodimethylamine µg/L 0.00069 -- 0.0014 -- -- CTR Dissolved Oxygen mg/L -- -- -- 4.0 [4] -- PO Flow MGD -- -- 5.1 -- -- DC Nitrate (as N) mg/L 10 -- -- -- -- TMDL Settleable Solids mL/L 0.1 -- -- -- -- PO Coliform MPN/100 mL [5] DPH Total Residual Chlorine µg/L [6] BP [1] C.F.R. – Based on federal regulations contained in 40 C.F.R. part 133. BP – Based on water quality objectives contained in the Basin Plan. CTR – Based on water quality criteria contained in the California Toxics Rule, and applied as specified in the SIP. DC – Based on the design capacity of the facility. PO – Based on the previous order (Order No. R3-2002-0043, modified 2005). TMDL – Based on applicable TMDL. DPH – Based on California Department of Public Health reclamation criteria for the reuse of wastewater. [2] In addition to concentration-based limitations and mass-based limitations for BOD5 and TSS, the Discharger is required to meet an 85 percent removal discharge specification. [3] Mass -based effluent limitations are established using the following formula: Mass (lbs/day) = flow rate (MGD) x 8.34 x effluent limitation (mg/L) where: Mass = mass limitation for a pollutant (lbs/day) Effluent limitation = concentration limit for a pollutant (mg/L) Flow rate = discharge flow rate (5.1 MGD) [4] The discharge shall not have a dissolved oxygen concentration less than 4.0 mg/L or so low that it adversely affects beneficial uses. [5] The median number of fecal coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by the results of bacteriological analyses for the last 7-days on which samples were taken. No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30-day period. The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [6] Compliance determinations for total chlorine residual shall be based on 99% compliance. To determine 99% compliance with effluent limitations for total chlorine residual, the following conditions shall be satisfied: 1) The total time during which the total chlorine residual values are above 0.01 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-27 2) No individual excursion from 0.01 mg/L shall exceed 30 minutes; and 3) No individual excursion shall exceed 2 mg/L. If grab sampling is used instead of continuous analysis: 1) The total number of excursions above 0.1 mg/L shall be no more than one individual excursion in any calendar month. 2) No individual excursion from 0.1 mg/L shall exceed 30 minutes, and must include results of no fewer than 2 grab samples. 3) No individual excursion shall exceed 2.0 mg/L. b. Toxicity. The discharge shall not contain substances in concentrations which are toxic to, or which produce detrimental physiological responses in human, plant, or animal (particularly fish or aquatic) life. E. Interim Effluent Limitations – Not Applicable F. Land Discharge Specifications – Not Applicable G. Recycling Specifications The Discharger currently produces and distributes tertiary treated recycled water within the City of San Luis Obispo. Recycled water is regulated under the City’s existing Master Reclamation Permit Order No. R3-2003-081, and therefore no additional specifications are applicable under this permit. V. RATIONALE FOR RECEIVING WATER LIMITATIONS A. Surface Water Receiving water quality is a result of many factors, some unrelated to the discharge. This Order considers these factors and is designed to minimize the influence of the discharge on the receiving water. Specific WQOs established by the Basin Plan to meet this goal for all inland surface waters are included as Receiving Water Limitations in section V.A of the Order. All receiving water limitations are retained from the previous Order. Dissolved oxygen limitation has been revised to be 7 mg/L year-round. The previous permit has seasonal dissolved oxygen limits of 5 and 7 mg/L. This was inconsistent with the Basin Plan water quality objectives, as the beneficial uses for San Luis Obispo Creek were not seasonally specified. The revision to 7 mg/L is consistent with the Basin Plan water quality objectives for spawning and cold water habitat. The revision is more restrictive than the previous seasonal limitation. The un-ionized ammonia limitation has been corrected as un-averaged limitation. The previous permit incorrectly associated a footnote indicating a running annual average limitation for unionized ammonia from Table 3.7 in the Basin Plan. However, that footnote only applies to total dissolved solids, boron, sulfate, sodium, and chloride. The revision is more restrictive than the previous limitation. B. Groundwater Groundwater limitations included in section V.B of the Order include general objectives as established in Chapter 3, Section II.A.4 of the Basin Plan and specific numeric WQOs for groundwater within the San Luis Obispo Creek sub area of the Estero Bay groundwater unit as established in Table 3-8 of the Basin Plan. VI. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS NPDES regulations at 40 C.F.R. § 122.48 require that all NPDES permits specify requirements for recording and reporting monitoring results. Water Code sections 13267 and 13383 also authorize the Central Coast Water Board to require technical and monitoring reports. Rationale for CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-28 the monitoring and reporting requirements contained in the Monitoring and Reporting Program (MRP), which is presented as Attachment E of this Order, is presented below. A. Influent Monitoring Influent monitoring is required to collect data on the characteristics of the wastewater and to assess compliance with effluent limitations (BOD5 and TSS percent reduction requirements). Monthly monitoring for BOD5 and TSS have been carried over from Order No. R3-2002-0043. Continuous flow monitoring has been established to monitor flow rates in relation to the design capacity of the Facility. B. Effluent Monitoring Effluent monitoring is required to determine compliance with effluent limitations contained in this Order and to determine contributions, if any, by the Discharger to receiving water exceedances above water quality objectives. In addition, annual effluent monitoring for priority toxic pollutants, Basin Plan pollutants, and Title 22 pollutants has been established to evaluate reasonable potential of the Discharger’s effluent to exceed water quality objectives/criteria during the next permit renewal process. Effluent monitoring requirements (i.e., sample type and frequency) have been carried over from Order No. R3-2002-0043, for the most part. Monitoring for selenium, cyanide, and bromoform has been reduced from monthly to annual, included with the annual monitoring requirement for all other priority pollutants. Monitoring for pentachlorophenol, and n-nitrosodimethylamine has been increased from annually to quarterly to resolve data quality uncertainties and determine compliance with the n-nitrosodimethylamine effluent limitation established in this Order. Monitoring for molybdenum has been established in this Order because it is a Basin Plan pollutant of concern and was not included in Order No. R3-2002-0043. An annual effluent monitoring requirement has been added to the Monitoring and Reporting Program (Attachment E). C. Whole Effluent Toxicity Testing Requirements Section 4 of the SIP requires a chronic toxicity effluent limitation in permits for all discharges that will cause, have reasonable potential to cause, or contribute to chronic toxicity in receiving waters. The SIP further requires that to determine compliance with the chronic aquatic life toxicity objective, the Central Coast Water Board shall require the use of short- term chronic toxicity tests. In addition, the Basin Plan establishes a narrative water quality objective for toxicity. Thus, to determine reasonable potential for toxicity and monitor compliance with water quality objectives for toxicity, annual monitoring of whole effluent toxicity (WET) (chronic and acute) has been carried over from Order No. R3-2002-0043. D. Receiving Water Monitoring 1. Surface Water The Basin Plan establishes water quality objectives for surface waters located within the Central Coast Region for the protection of beneficial uses. Receiving water monitoring is carried over from Monitoring and Reporting Program R3-2002-0043 to monitor compliance with the receiving water limitations contained in this Order. 2. Groundwater Consistent with the previous permit, groundwater monitoring requirements have not been included. E. Other Monitoring Requirements 1. Solids/Biosolids Monitoring CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-29 Biosolids monitoring is required to ensure compliance with the biosolids disposal requirements. Biosolids disposal requirements are imposed pursuant to 40 C.F.R. part 503 to protect public health and prevent groundwater degradation. Biosolids monitoring shall be reported in the annual report in accordance with 40 C.F.R. part 503. Biosolids monitoring requirements have been retained from the previous Order. 2. Pretreatment Monitoring Pretreatment monitoring shall be reported in the Annual Report in accordance with requirements of 40 C.F.R. § 403.8. Pretreatment monitoring requirements have been retained from the previous Order. 3. Salt and Nutrient Management Plan Reporting Salt and Nutrient Management Plan reporting requirements have been established in this Order to help identify and reduce salt and nutrient loading in the effluent. This salt/nutrient management report shall be included as part of the Annual Report. VII. RATIONALE FOR PROVISIONS A. Standard Provisions Standard Provisions, which apply to all NPDES permits in accordance with 40 C.F.R. §122.41, and additional conditions applicable to specified categories of permits in accordance with 40 C.F.R. §122.42, are provided in Attachment D. The discharger must comply with all standard provisions and with those additional conditions that are applicable under section 122.42. Sections 122.41(a)(1) and (b) through (n) of 40 C.F.R. establish conditions that apply to all state-issued NPDES permits. These conditions must be incorporated into the permits either expressly or by reference. If incorporated by reference, a specific citation to the regulations must be included in the Order. Section 123.25(a)(12) of 40 C.F.R. allows the state to omit or modify conditions to impose more stringent requirements. In accordance with 40 C.F.R. §123.25, this Order omits federal conditions that address enforcement authority specified in 40 C.F.R. §§122.41(j)(5) and (k)(2) because the enforcement authority under the Water Code is more stringent. In lieu of these conditions, this Order incorporates by reference Water Code section 13387(e). B. Special Provisions 1. Reopener Provisions The Order may be modified in accordance with the requirements set forth at 40 C.F.R. parts 122 and 124, to include appropriate conditions or limits based on newly available information, or to implement any, new State water quality objectives that are approved by the USEPA. As effluent is further characterized through additional monitoring, and if a need for additional effluent limitations becomes apparent after additional effluent characterization, the Order will be reopened to incorporate such limitations. 2. Special Studies and Additional Monitoring Requirements a. Toxicity Reduction Requirements The Order retains the requirement to perform a TRE, if the acute toxicity limitation is exceeded or if chronic toxicity is detected in the effluent above 1 TUc. When toxicity monitoring measures acute or chronic toxicity in the effluent above the limitations established by the Order, the Discharger is required to resample and retest. When all monitoring results are available, the Executive Officer can determine CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-30 whether to initiate enforcement action, whether to require the Discharger to implement TRE requirements, or whether other measures are warranted. b. Facilities Evaluation The report of waste discharge submitted states that the City’s average dry weather flow is approximately 4.5 MGD and that the facility has a design capacity of 5.1 MGD. The current average dry weather flow therefore represents 88% of the design capacity. Based on that data, it appears that the monthly average daily flow will or may reach design capacity during the term of this permit. Pursuant to Central Coast Standard Provisions, the Discharger shall evaluate the need for future expansion of the Facility to accommodate future growth within the City of San Luis Obispo. The evaluation shall quantify future flows to the plant from indirect dischargers, California State Polytechnic University and San Luis Obispo County Airport, and future annexations to the City of San Luis Obispo. This evaluation shall be completed with the planned Facility upgrades to be completed during the term of this permit and submitted to the Central Coast Water Board with the Engineering Report for the Facility upgrades. 3. Best Management Practices and Pollution Prevention a. Salt and Nutrient Management Program Section G of the previous Order (R3-2002-0043) required the Discharger to conduct a Salt Management Study to control levels of TDS, chloride, sodium, sulfate, and boron (collectively referred to as salts) in discharges from the Facility and attain applicable WQOs for salts in the San Luis Obispo Creek Sub-Basin of the Estero Bay Drainage Basin. The Discharger shall develop and implement a Nutrient Management Program as part of the Salt and Nutrient Management Program, as discussed in section VI.C.3.a of this Order, based on the Recycled Water Policy discussed in section III.E.3 of this Fact Sheet. 4. Construction, Operation, and Maintenance Specifications 5. Special Provisions for Municipal Facilities (POTWs Only) a. Biosolids Management The use and disposal of biosolids is regulated under federal and State laws and regulations, including permitting requirements and technical standards included in 40 C.F.R. part 503. The Discharger is required to comply with the standards and time schedules contained in 40 C.F.R. part 503. Title 27, CCR, Division 2, Subdivision 1, Section 20005 establishes approved methods for the disposal of collected screenings, residual sludge, biosolids, and other solids removed from liquid wastes. Requirements to ensure the Discharger disposes of solids in compliance with State and federal regulations have been included in this Order. These requirements have been retained from the previous Order. b. Pretreatment Requirements The federal CWA, Section 307(b), and federal regulations, 40 C.F.R. part 403, require publicly owned treatment works to develop and implement an acceptable industrial pretreatment program. A pretreatment program is required to prevent the introduction of pollutants, which will interfere with treatment plant operations or CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-31 sludge disposal, and prevent pass through of pollutants that exceed water quality objectives, standards or permit limitations. Pretreatment requirements are imposed pursuant to 40 C.F.R. part 403. 6. Other Special Provisions a. Discharges of Storm Water. Discharges of storm water from POTWs with a design capacity greater than 1.0 MGD are eligible for coverage under General State Water Board Order 97-03-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Dischargers of Storm Water Associated with Industrial Activities Excluding Construction Activities. The design capacity of the Facility is greater than 1.0 MGD. Therefore, the Discharger shall seek coverage under General Permit No. CAS000001 for all storm water discharges. This is retained from the previous Order. b. Statewide General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order 2006-0003-DWQ). The Order requires coverage by and compliance with applicable provisions of General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order 2006- 0003-DWQ). This General Permit, adopted on May 2, 2006, is applicable to all “federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California.” The purpose of the General Permit is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. Furthermore, the General Order contains requirements for operation and maintenance of collection systems and for reporting and mitigating sanitary sewer overflows. Inasmuch that the Discharger’s collection system is part of the system that is subject to this Order, certain standard provisions are applicable as specified in Provisions, section VI.C.5. For instance, the 24-hour reporting requirements in this Order are not included in the General Order. The Discharger must comply with both the General Order and this Order. The Discharger and public agencies that are discharging wastewater into the facility were required to obtain enrollment for regulation under the General Order by December 1, 2006. This provision is retained from the previous Order. 7. Compliance Schedules – Not Applicable VIII. PUBLIC PARTICIPATION The Central Coast Water Board is considering the issuance of WDRs that will serve as an NPDES permit for the City of San Luis Obispo Water Resource Recovery Facility. As a step in the adoption process, Central Coast Water Board staff has developed tentative WDRs and is encouraging public participation in the WDRs adoption process. A. Notification of Interested Parties The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provided an opportunity to submit written comments and recommendations. Notification was provided through written publication in the Tribune newspaper and posting on the Central Coast Water Board’s website. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-32 The public had access to the agenda and any changes in dates and locations through the Central Coast Water Board’s website at http://www.waterboards.ca.gov/centralcoast/ B. Written Comments Interested persons were invited to submit written comments concerning tentative WDRs as provided through the notification process. Comments were due either in person or by mail to the Executive Officer at the Central Coast Water Board at the address on the cover page or via electronic mail to centralcoast@waterboards.ca.gov. To be fully responded to by staff and considered by the Central Coast Water Board, the written comments were due at the Central Coast Water Board office by 5:00 p.m. on July 25, 2014. On July 24, 2014, the Discharger submitted written comments stating they were in agreement with the requirements of the proposed Order, but had a few remaining comments as described below: 1. N-Nitrosodimethylamine (NDMA)- The Discharger disputed the need for an effluent limit for NDMA. The effluent limit for NDMA is the result of detection in one of six samples in the RPA (see pages F-14 through F-20 for the rationale for NDMA effluent limit), at a relatively high concentration for municipal effluent. The Discharger quoted the SIP statement as follows: “The RWQCB shall have discretion to consider if any data are inappropriate or insufficient for use in implementing this Policy. Instances where such consideration is warranted include,…evidence that a sample…is not representative of the effluent or ambient receiving water quality…” The Discharger concluded that the detection of NDMA was not representative of the City’s effluent, and requested that an NDMA effluent limitation not be established. Staff response: The full text of the statement in the SIP the Discharger referred to includes “instances where such consideration is warranted include, but are not limited to, the following: evidence that a sample has been erroneously reported or is not representative of effluent or ambient receiving water quality, questionable quality control/quality assurance practices; and varying seasonal conditions.” The discretion at question here is the determination whether the sample is representative of the effluent. In this case, there is no compelling reason to consider the sample unrepresentative of the effluent. The laboratory data quality objectives for the detection were met, the sample was collected properly, and no other reason can be found to invalidate the detection. The relatively high concentration is not reason in and of itself to conclude the sample is unrepresentative. In fact, the SIP and RPA are written with methodologies to address these situations. Staff recommends establishing the proposed NDMA effluent limitation and the proposed increased NDMA sampling frequency, consistent with the SIP and RPA methodologies. 2. Mass Effluent Limitations – The Discharger stated, “during wet weather, due to higher flows, the concentration based limits in Table 4 would be met but the mass limitations may be exceeded and beneficial uses will not be impacted.” The Discharger has requested language be included that states effluent mass limitations will not apply in those instances. The Discharger cites specific language from City of Davis’s permit (Central Valley Region). Staff response: According to 40 CFR 122.45, design flow rate and mass-based limitations are fundamental in establishing effluent limitations: CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-33 (b) Production-based limitations. (1) In the case of POTWs, permit effluent limitations, standards, or prohibitions shall be calculated based on design flow. (f) Mass limitations. (1) All pollutants limited in permits shall have limitations, standards or prohibitions expressed in terms of mass except: (i) For pH, temperature, radiation, or other pollutants which cannot appropriately be expressed by mass; (ii) When applicable standards and limitations are expressed in terms of other units of measurement; or (iii) If in establishing permit limitations on a case-by-case basis under § 125.3, limitations expressed in terms of mass are infeasible because the mass of the pollutant discharged cannot be related to a measure of operation (for example, discharges of TSS from certain mining operations), and permit conditions ensure that dilution will not be used as a substitute for treatment. (2) Pollutants limited in terms of mass additionally may be limited in terms of other units of measurement, and the permit shall require the permittee to comply with both limitations. Effluent flow multiplied by pollutant concentration will equal mass-based discharge as described in the footnotes of Table F-5. Unlinking the concentration from the flow, as proposed by the Discharger’s comments, would be inappropriate and not consistent with 40 CFR 122.45(f)(2). Mass-based limitations are still to be enforced, even during times of high flow due to wet weather. On a practical basis, the wet weather flows are expected to decrease concentrations for pollutants entering the treatment works. The cited permit language is consistent with 40 CFR 122.45, and staff does not recommend including it in this proposed Order. 3. Chronic Toxicity Test Species – The Discharger has concerns that Selenastrum species required in the 3-month toxicity screening test may yield false positives. The Discharger requests (1) the toxicity testing procedure be limited to fathead minnows and water fleas, (2) the City’s concerns for false positives be added to Section VI.C of the Fact Sheet, and (3) the potential for false positives be considered when selecting the most sensitive species upon which to base testing following the screening period. Staff Response: The three test species required in this permit are consistent with and derived from U.S. EPA approved methods for chronic toxicity testing found in Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, 2002. The methods included in that publication are referenced in Table 1A, 40 CFR Part 136 regulations and, therefore, constitute approved methods for chronic toxicity tests. The use of any test specifies or test conditions other than those described in the methods shall be subject to application and approval of alternat ive test procedures under 40 CFR 136.4 and 40 CFR 136.5. The Discharger’s request is for a procedure not consistent with the methodology approved under 40 CFR 136; therefore, staff does not recommend any changes to the required test species. If the results of the screening result in suspected false positives according to the Discharger, Water Board CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-34 staff will consult with U.S. EPA regarding the reliability of the results in consideration of the data validation requirements in the approved methodology. 4. Annual Self-Monitoring Report Date – The Discharger has requested the reporting deadline in Section VIII.D.8 of Attachment D (page D-13) and Section VI.C.3.a.iv (page 11) be changed to February 15. Staff Response: Annual self-monitoring summary reports are typically due by February 1st, according to Standard Provisions adopted by the Central Coast Water Board in January 2013. The proposed Order grants the Discharger an exception to this date and extends the deadline to February 15th. This exception is noted on page E-17 (footnote to Table E- 6) of the proposed Order, and a correction has been made, as requested, to page 11 to be consistent. Staff does not recommend changing the language or dates in the adopted Standard Provisions (page D-13), as that language was specifically adopted by the Central Coast Water Board. The language on page E-17 and page 11 clearly indicates February 15th is a revision to the standard February 1st deadline and adequately addresses the Discharger’s concerns. C. Public Hearing The Central Coast Water Board held a public hearing on the tentative WDRs during its regular Board meeting on the following date and time and at the following location: Date: September 25-26, 2014 Time: 8:30 a.m. Location: Central Coast Water Board Offices 895 Aerovista Drive, Suite 101 San Luis Obispo Interested persons were invited to attend. At the public hearing, the Central Coast Water Board invited interested parties to provide testimony pertinent to the discharge, WDRs, and permit. For accuracy of the record, important testimony is requested in writing. D. Reconsideration of Waste Discharge Requirements Any aggrieved person may petition the State Water Board to review the decision of the Central Coast Water Board regarding the final WDRs. The petition must be received by the State Water Board at the following address within 30 calendar days of the Central Coast Water Board’s action: State Water Resources Control Board Office of Chief Counsel P.O. Box 100, 1001 I Street Sacramento, CA 95812-0100 For instructions on how to file a petition for review, see http://www.waterboards.ca.gov/public_notices/petitions/water_quality/wqpetition_instr.shtml E. Information and Copying The Report of Waste Discharge, other supporting documents, and comments received are on file and may be inspected at the address above at any time between 8:00 a.m. and 5:00 p.m., Monday through Friday. Copying of documents may be arranged through the Central Coast Water Board by calling (805) 549-3147. CITY OF SAN LUIS OBISPO ORDER NO. R3-2014-0033 WATER RESOURCE RECOVERY FACILITY NPDES NO. CA0049224 ATTACHMENT F – FACT SHEET F-35 F. Register of Interested Persons Any person interested in being placed on the mailing list for information regarding the WDRs and NPDES permit should contact the Central Coast Water Board, reference this facility, and provide a name, address, and phone number. G. Additional Information Requests for additional information or questions regarding this Order should be directed to Katie DiSimone at (805) 542-4638 or katie.disimone@waterboards.ca.gov or Sheila Soderberg at (905) 549-3592 or sheila.soderberg@waterboards.ca.gov. 68 From:Regulatory <regulatory-bounces@lists.casaweb.org> on behalf of Maile Lono-Batura via Regulatory <regulatory@lists.casaweb.org> Sent:Friday, March 21, 2025 2:31 PM To:Greg Kester via Regulatory Cc:Maile Lono-Batura Subject:[Regulatory] FW: Drying Reduces PFAS - Paper from WRF Project Attachments:Drying reduces PFAS in biosolids_2025.pdf; ATT00001.txt This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Hello everyone, Please find the attached and linked WRF project that focused on the viability of drying to reduce total PFAS concentrations in biosolids. This study looked at both lab and full-scale facility potential for removal with average PFAS removal being approximately 80%. Read the study report for additional details. Please feel free to share with those that may be interested. Thank you. Maile Lono-Batura, BCES, MNPL Director of Renewable Resources CA Association of Sanitation Agencies casaweb.org | @casa_cleanwater | casacleanwater From: McNamara, Patrick <McNamaraP@bv.com> Date: Friday, March 21, 2025 at 7:56 AM To: Magruder, Matt <MMagruder@mmsd.com>, Jordan Damerel <jdamerel@fairfieldsuisunsewer.ca.gov>, Peter Kistenmacher <pkistenmacher@cmsa.us>, Maltos, Rudy <RMaltos@MetroWaterRecovery.com>, Perez, Natalia <NPerez@dep.nyc.gov>, janine@nebiosolids.org <janine@nebiosolids.org>, Maile Lono-Batura <mlono-batura@casaweb.org>, Jacqueline Zipkin <JZipkin@ebda.org>, Mark Koekemoer <mkoekemoer@cmsa.us>, fieldingjk@trinityra.org <fieldingjk@trinityra.org>, Bailey, Erika <Erika.Bailey@raleighnc.gov> Cc: Enson, Jennifer T. <EnsonJT@bv.com>, Moss, Lynne H <MossLH@bv.com>, Downing, Leon <DowningL@bv.com>, Carr, Scott <CarrJS@bv.com>, Guven, Engin <GuvenE@bv.com> Subject: Drying Reduces PFAS - Paper from WRF Project Dear Partners of WRF Project 5211, I am pleased to attach our recent publication on the impacts of drying on PFAS in biosolids. This research stems from our WRF project. We thank you again for all of your support along the way. We are looking forward to future publications stemming from this work as well. 69 This is an open-access article. Please feel free to share with anyone who might be interested. The pdf is attached and a link is here: Drying reduces the total PFAS concentration in biosolids and alters the PFAS profile - Environmental Science: Water Research & Technology (RSC Publishing) DOI:10.1039/D4EW00890A Sincerely, Patrick Patrick J. McNamara, Ph.D., P.E.*, | Wastewater Process Engineer Black & Veatch|111 E. Wisconsin Avenue, Suite 1770, Milwaukee, WI 53202 +1 414-455-1579 P | McNamaraP@BV.com *Licensed in Wisconsin Building a World of Difference.® Please consider the environment before printing my email Please note that the information and attachments in this email are intended for the exclusive use of the addressee and may contain confidential or privileged information. If you are not the intended recipient, please do not forward, copy or print the message or its attachments. Notify me at the above address, and delete this message and any attachments. Thank you. Disclaimer The information contained in this communication from the sender is confidential. It is intended solely for use by the recipient and others authorized to receive it. If you are not the recipient, you are hereby notified that any disclosure, copying, distribution or taking action in relation of the contents of this information is strictly prohibited and may be unlawful. This email has been scanned for viruses and malware, and may have been automatically archived by Mimecast, a leader in email security and cyber resilience. Mimecast integrates email defenses with brand protection, security awareness training, web security, compliance and other essential capabilities. Mimecast helps protect large and small organizations from malicious activity, human error and technology failure; and to lead the movement toward building a more resilient world. To find out more, visit our website. file:///C/...bispo/Documents/PRR26230%20Jorgensen%20-%20WRRF%20Biosolids/Emails/1001-End%20Folder/Attachments/ATT00001.txt[8/25/2026 2:03:58 PM] _______________________________________________ Regulatory mailing list Regulatory@lists.casaweb.org http://lists.casaweb.org/mailman/listinfo/regulatory_lists.casaweb.org Environmental Science Water Research & Technology PAPER Cite this: DOI:10.1039/d4ew00890a Received 1st November 2024, Accepted 5th March 2025 DOI: 10.1039/d4ew00890a rsc.li/es-water Drying reduces the total PFAS concentration in biosolids and alters the PFAS profile† Patrick J. McNamara, *ab Jessica Calteux, b Eric Redman, c Taryn McKnight, c Lynne Moss, a Webster Hoener, a Scott Carr a and Zhongzhe Liu d While per- and polyfluoroalkyl substances (PFAS) are not actually generated at water resource recovery facili- ties (WRRFs), utilities are being forced to consider PFAS in biosolids management plans due to mounting polit- ical pressure and pending regulations.Emerging thermal technologies including pyrolysis, gasification, and su- per critical water oxidation have garnered recent attention for PFAS destruction. Drying, however, is a conventional technology that might also be a tool for utilities to manage PFAS in biosolids, but research on the impacts of drying on PFAS in biosolids is scarce. The objective of this research was to determine how dry- ing affected the fate of PFAS in biosolids. Full-scale sampling was paired with lab-scale oven drying experi- ments to understand the impact of drying on measurable PFAS in biosolids. Overall, drying substantially re- duced the total PFAS concentration in biosolids. PFAS removal during a full-scale facility's drying process matched the removal achieved when solids were taken from that facility and dried in a lab-scale oven instead, with average PFAS removal being approximately 80%. Precursors to perfluoroalkyl acids (PFAAs), primarily 5:3 fluorotelomer carboxylic acid (FTCA) and 6:2 FTCA, as well as perfluorooctane sulfonic acid (PFOS) were sub- stantially reduced between pre-drying and post-drying triplicate samples. Additional lab-scale oven drying ex- periments corroborated that measurable PFAS were removed from biosolids collected from three different utilities. Drying experiments at 30 °Cand105°C revealed that the PFAS profiles were similar, but PFAS con- centrations were lower in the 105 °C samples compared to 30 °C samples. While more research is necessary to determine and validate the removal mechanism, drying could be a viable technology to reduce measurable PFAS levels in biosolids to concentrations below guidelines forlandapplication. 1. Introduction Per- and polyfluoroalkyl substances (PFAS) have altered the biosolids management landscape. Though water resource re- covery facilities (WRRFs) are not actually a source of PFAS, they receive and convey PFAS because of the widespread use of PFAS in society and consumer products. 1 PFAS are abun- dant in a range of products including cosmetics, water-proof clothing, carpets, and fast-food wrappers. 2–5 PFAS are widely detected in people, including breastmilk, blood, and urine samples, and therefore municipal sewage also contains PFAS.6–8 Moreover, consumer products laden with PFAS are sent to landfills where products degrade over time, and PFAS are released into leachate that is often sent to the head of a WRRF.3,9,10 The concentration in biosolids depends on any nearby industrial sources of PFAS discharged to the WRRF as well as the unit operations used at the WRRF. 2,11–13 Some Eu- ropean countries, Australia, Canada, and states in the United States have set limits for PFAS concentrations in soil, and some states in the United States have set PFAS concentration limits for biosolids that can be land applied to minimize hu- man health impacts. 7,14–20 Biosolids management requires an understanding of how biosolids handling technologies impact the fate of PFAS. Emerging technologies, in particular thermal processes, have Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 a Black & Veatch, USA. E-mail: McNamaraP@bv.com b Marquette University, USA c Eurofins Environment Testing, USA d California State University, Bakersfield, USA †Electronic supplementary information (ESI) available. See DOI:https://doi.org/ 10.1039/d4ew00890a Water impact PFAS have substantially altered the biosolids management industry. Emerging technologies offer a means to reduce PFAS to non-detect levels in solid prod- ucts such as biochar. Drying, however, is a widely employed technology that could sufficiently reduce PFAS levels to meet guidelines for land application.Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online View Journal Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 garnered attention for their potential to reduce PFAS concen- trations in solids. 21,22 Indeed, pyrolysis has been shown to re- move and transform PFAS at the lab and pilot scale. 23–29 In- cineration, a more established technology, also removes the majority of PFAS from the solid phase. 30 Pyrolysis and gasifi- cation are still emerging technologies in the biosolids mar- ketplace, and both of these technologies require drying first.23,31 Drying, however, is already a widely used and estab- lished solids handling process. Aside from being useful when paired with emerging thermal technologies, drying offers the benefit of substantial mass reduction via removal of water. As numerous utilities already dry and land apply biosolids, it is important to understand the impacts of drying on the fate of PFAS in biosolids. Limited studies have been conducted thus far regarding the potential impacts of drying on PFAS fate, and results have been mixed. 32–34 Indeed, heat treatment of wastewater solids at 480–650 °C led to an increase in total perfluoroalkyl acids (PFAAs) by 53%, mainly due to perfluorohexanoic acid (PFHxA) increases. 12 In another study, heat drying at 90–120 °C was found to increase PFAS concentrations, in particular the concentration of fluorotelomer phosphate diesthers (diPAPs).32 A lab study on drying at 115 °C at 2 hours found that 6:2 diPAP approximately doubled; perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) were similar before and after heat treatment; and perfluoropenta- noic acid (PFPeA) decreased by approximately 50%. 32 One study on a full-scale dryer with a regenerative thermal oxi- dizer (RTO) found that 50–90% of PFAS were transferred from the biosolids to the gas phase, and 18 PFAS were detected in the gas phase headed for treatment in the RTO. 34 Despite widespread use of drying in the industry, limited studies are available that document the impacts of drying on the fate of PFAS in biosolids. The objective of this research was to determine the impact of drying on PFAS in biosolids. As some government regula- tory agencies move towards implementing concentration- based limits for PFAS in biosolids and soils, it is particularly important to know how drying processes impact measurable PFAS concentrations. This research combined sampling at a full-scale dryer with lab-scale oven drying experiments on the same full-scale pre-drying solids samples. Additionally, pre- drying solids samples provided by three different WRRFs were used for lab-scale oven drying experiments. Finally, lab- scale oven drying experiments were conducted on high mois- ture content (MC) samples at 30 °C and 105 °C. 2. Methods and materials 2.1. Comparison of full-scale drying to lab-scale oven drying on PFAS concentrations in biosolids A WRRF agreed to provide pre-drying and post-drying sam- ples from their full-scale dryer under conditions of anonym- ity. The average influent flow rate to this WRRF is over 50 million gallons per day (MGD). Liquid treatment steps in- clude grit removal, primary clarification, conventional acti- vated sludge, and chlorination. Solids undergo thickening and dewatering prior to drying. The total solids (TS) content for the pre-drying solids fed to the dryer was approximately 16% TS, and the TS content for the post-drying solids taken from the effluent of the dryer was approximately 90% TS. Triplicate pre-drying samples and triplicate post-drying sam- ples were collected on-site from the full-scale dryer. In addi- tion to full-scale sampling, pre-drying solids samples were dried in triplicate in a lab-scale oven at 105 °C for 5 hours to compare lab-scale oven drying to full-scale drying. All sam- ples were sent to Eurofins Environment Testing USA (Eurofins) for PFAS extraction and analysis as described in section 2.4. 2.2. Lab-scale oven drying of solids from three different WRRFs Solids from three different WRRFs were dried in a lab-scale oven to assess if PFAS removal was observed when drying dif- ferent solids. The three WRRFs tested for this experiment were from different states than the WRRF described in sec- tion 2.1. Each WRRF requested to be kept anonymous and provided the following general information to provide context on their biosolids without revealing their identity. WRRF A re- ceives less than 25 MGD of wastewater influent. Liquid pro- cesses include primary treatment and secondary treatment that has full nitrification and one train with anoxic zones for incidental denitrification. Primary sludge and thickened waste activated sludge (WAS) are sent to a mesophilic anaero- bic digester. A portion of digested solids are sent to a screw press, and effluent samples from the screw press were col- lected for this work. The TS content was 18.3%. WRRF B is over 50 MGD and utilizes a two-stage anaerobic digestion process. The first stage is fed a mixture of primary sludge and WAS and has a solids retention time (SRT) of 2 days or less. The second stage has an SRT of 15–20 days. The digestate is processed through a centrifuge. Effluent samples from the centrifuge were collected for this work. The TS con- tent was 20.8%. WRRF C is less than 10 MGD. The WRRF em- ploys primary clarification, and solids from the primary clari- fiers are pumped directly to anaerobic digesters. The WRRF employs activated sludge, and the WAS is thickened and then pumped directly to the anaerobic digesters as well. After an- aerobic digestion, centrifuges are used for dewatering. Efflu- ent samples from the centrifuges were collected for this work. The TS content was 24.2% TS. The collected pre-drying solids samples were shipped to a laboratory at California State University-Bakersfield (CSU-B) for lab-scale oven drying. Samples were stored at 4 °C until used for the experiment. Storage was less than 7 days.“Pre- drying”refers to solids that were received from the WRRFs before undergoing any drying.“Post-drying”refers to solids after they were dried in the lab-scale oven. Approximately 20 g of pre-drying solids were placed in a drying tin. The sam- ples were dried overnight (24 hours) at 105 °C in a conven- tional lab-scale oven with the fan mode on. After drying, Environmental Science: Water Research & TechnologyPaper Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 samples were transferred to containers that were provided by Eurofins for PFAS analysis. Dried samples were stored in the dark at room temperature until shipped to Eurofins. Pre- drying and post-drying samples were shipped to Eurofins for targeted analysis of PFAS as described in section 2.4. 2.3. Lab-scale oven drying experiments on high moisture content samples at 30 °C and 105 °C High moisture content samples (99.8% MC, 0.2% TS) were dried to assess PFAS profiles in biosolids dried at two different temperatures. Triplicate biosolids drying experiments were con- ducted at 105 °C at the CSU-B laboratory and at the lower tem- perature of 30 °C. The 105 °C test was conducted overnight and the 30 °C test lasted 5 days. The 30 °C test was conducted in a lab-scale oven with the temperature lowered to 30 °C. These ex- periments were also conducted to assess the possibility of PFAS sticking to the drying tins. After the first set of experiments con- ductedinsection2.1withresultsshowninsection3.1,it seemed feasible that PFAS previously associated with water could stick to the drying tin (and not the solids) as the water evaporated. This possibility was tested by employing a ‘wipe kit’ provided by Eurofins. This kit includes a methanol-soaked cloth that is used to wipe the tin after biosolids are completely re- moved for sampling following drying. 2.4. PFAS analysis Sixty targeted PFAS analytes were measured. They are all listed by chemical class in the ESI document (ESI†), Table S1. The associated Isotope Dilution Analytes (IDAs), also known as isotopically labeled analogs, used for each PFAS analyte are also listed in ESI†Table S1. PFAS analyses were per- formed on a SCIEC 5500+ triple quad LC/MS/MS system oper- ated in multiple reaction monitoring (MRM) mode. Biosolid samples were manually mixed in their collection containers and then subsampled (nominally 1 g for both pre-drying and post-drying samples). Each subsample was fortified with IDAs of the native target analytes, then extracted via sonication with basic methanol for one hour. The resulting extracts were re-constituted in water and then cleaned up via solid phase extraction (SPE) using a WAX SPE cartridge (Strata X-AW or equivalent), which retains the desired PFAS. The IDAs and target analytes were then eluted from the SPE cartridge with basic methanol and adjusted to a final extract volume of 10 ml in 80:20 methanol/water, after additional fortification with 13C2-PFOA as the internal standard (ISTD). Identical sample extraction procedures were applied to pre-drying and post-drying biosolid samples. Accuracy of measurements for the reported list of 60 target analytes is ensured via initial and ongoing assessment of accu- racy and precision via laboratory control sample aliquots, con- trol sample duplicates, laboratory method blanks, method de- tection limit (MDL) studies, MDL verification aliquots, and performance testing studies. Each of these is performed as de- scribed in the associated laboratory Standard Operating Proce- dures (SOPs), and the results are monitored and validated via 3rd party laboratory accreditation bodies for the corresponding regulatory programs including the National Environmental Lab- oratory Accreditation Program and the United States Depart- ment of Defense Environmental Laboratory Accreditation Program. Within each sample, additional measures of method per- formance are monitored, including IDA recovery, ISTD re- sponse, analyte retention times, analyte ion ratios, and ana- lyte signal-to-noise ratios. Each of these sample-specific quality controls or identification elements must meet the criteria specified in the corresponding laboratory SOPs. PFAS concentrations are reported on a dry weight basis whereby dry weight is determined when moisture has been removed at 105 °C and the sample has been cooled to room tempera- ture in a desiccator. 2.5. Analysis & Statistics To conduct conservative statistical analyses on the fate of PFAS during drying, the reporting limits (RLs) provided in the Eurofins PFAS analysis report were used to fill in the gaps of the non-detects in the triplicate data before percent re- moval or significance of species removal was determined,i.e., “zero”values were not used for statistics. Note that these RL data are not reflected in the figures; only species concentra- tions higher than the reporting limits are shown. Statistical analysis was conducted using GraphPad Prism v10.3.1 (GraphPad Software, La Jolla, CA). The tests con- ducted for each experiment are listed in the ESI†Tables S5, S8, & S16.P-values <0.05 were considered statistically signifi- cant. Concentrations of PFAS were normalized and reported in micromoles (μmol) of F per kg dry solids, where the F con- tent stemmed from the moles of F present in the species of PFAS that were measured through targeted analysis. These concentrations were used to calculate percent removals. 3. Results 3.1. Impacts of full-scale drying and lab-scale oven drying on PFAS in biosolids 3.1.1. Full-scale dryer results.Thefull-scaledryerreduced the mass of detectable PFAS and changed the measurable PFAS profiles between the pre-drying and post-drying samples (Fig. 1 and ESI†Tables S2 & S3). Ten PFAS were detected across all three pre-drying samples for the full-scale dryer. The most abun- dant species in the pre-drying samples was 5:3 fluorotelomer carboxylic acid (FTCA), and 6:2 FTCA was the third most abun- dant species. These FTCA compounds are common precursors to short-chain PFAAs;‘precursors’are chemical species known to degrade and transform into other species of PFAS. 35–37 PFOS was the second most abundant PFAS overall in the pre-drying samples, and the most abundant PFAA. Of the ten PFAS de- tected across all three pre-drying samples, seven were detected aboveRLinallthreepost-dryingsamples.7:3FTCAwasde- tected in two of the three post-drying samples, perfluorodecanoic acid (PFDA) was detected in one of the three post-drying samples, and 6:2 FTCA was not detected in any of Environmental Science: Water Research & Technology Paper Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 the post-drying samples (Fig. 1 and ESI†Tables S2 & S3). Two PFAAs, specifically perfluoropentanoic acid (PFPeA) and perfluorohexane sulfonic acid (PFHxS), were detected across all three post-drying samples, but not in any of the pre-drying sam- ples. These two PFAAs were present at concentrations in the post-drying samples that were below the RLs for the pre-drying samples (ESI†TablesS3&S4).Therefore,itisnotpossibleto know if these two PFAAs appeared during the drying process due to a reaction or if they were already present in the pre- drying samples but could not be detected. 12,38 In general though, the PFAS fraction attributed to precursor compounds, i.e., FTCA, fluorotelomer sulfonic acids (FTS), perfluorooctane sulfonamido acetic acids (FOSAA), and perfluorooctane sulfo- namido ethanols (FOSE), decreased significantly during drying (ESI†Fig. S1, Tables S7 & S8). 35–37 3.1.2. Lab-scale oven drying results.The solids samples collected before entering the full-scale dryer were also dried in a lab-scale oven at 105 °C to compare the impacts of lab- scale oven drying to full-scale drying on the PFAS profile in biosolids. The lab-scale oven data reflected similar trends as the full-scale dryer data. Total PFAS were reduced and the profile changed (Fig. 2). Of the ten PFAS detected across all three pre-drying samples, four were detected above RL in all three post-drying samples (ESI†Tables S3 & S4). One species, PFHxS, a terminal PFAA, appeared in all three lab-scale oven post-drying samples despite not being detected in the pre- drying samples. Similar to the full-scale dryer post-drying samples, PFOS was detected in all three lab-scale oven post- drying samples and was the second most abundant species detected after 5:3 FTCA. Together, 5:3 FTCA and PFOS ac- counted for, on average, more than half of the molar F as PFAS concentration in the lab-scale oven post-drying samples and full-scale dryer post-drying samples. There was no signif- icant difference between the concentrations of these two spe- cies from the two drying methods (ESI†Table S5). Lab-scale oven drying also decreased the ratio of precursor species to total PFAS in biosolids (ESI†Fig. S1, Tables S7 & S8), which is consistent with the full-scale dryer sample data. Overall, the full-scale dryer and lab-scale oven drying ex- periments revealed substantial reductions in measurable PFAS in the biosolids (Fig. 3). The average PFAS removal in the full-scale dryer was 84.9% and the average PFAS removal in the lab-scale oven was 81.9% (ESI†Table S9). Average re- moval of total PFAS was not significantly different between the full-scale dryer and the lab-scale oven (ESI†Table S8). These results indicate that drying biosolids could be a viable option to reduce the measurable PFAS concentration in bio- solids, and, for these particular systems, the lab-scale oven setup can be used to help estimate removal percentage for the majority of detectable PFAS in biosolids in a full-scale system. On a PFAS mass concentration basis, pre-drying total PFAS concentrations ranged from approximately 100–150 μgkg-1 (ESI†Table S3). The full-scale dryer post-drying samples had a wider range of concentrations than the lab-scale oven post- drying samples. The full-scale dryer post-drying samples total PFAS concentration ranged from 13–31 μgkg-1,andthelab- scale oven post-drying samples ranged from 16–23 μgkg-1. Some states have employed interim guidelines for land applica- tion of biosolids that set 20 μgkg-1 of PFOS and PFOA as a threshold wherein any concentrations below this level can be land applied. 40 The pre-drying biosolids samples had PFOS and PFOA concentrations already below this threshold. 3.2. Impact of lab-scale oven drying on PFAS in biosolids from three different utilities Biosolids samples were collected anonymously from three WRRFs that were unique from the WRRF that provided samples for the results presented in section 3.1 above. The biosolids samples were collected from different WRRFs with varying Fig. 1 Full-scale drying reduces measurable PFAS concentrations in biosolids. Samples were collected in triplicate (n = 3). Reprinted with permission.©The Water Research Foundation. 39 Fig. 2 Lab-scale oven drying at 105 °C reduces measurable PFAS concentrations in biosolids. Triplicate lab-scale oven drying experi- ments were conducted (n = 3). Reprinted with permission.©The Water Research Foundation. 39 Environmental Science: Water Research & TechnologyPaper Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 influent flow rates and unit operations as described in the methods section. Regardless of biosolids sample, the total sum of measurable PFAS decreased after drying (Fig. 4, ESI†Tables S10 & S11). For all three pre-drying samples, 5:3 FTCA was the first or second most abundant PFAS. PFOS was one of the three most abundant PFAS in each pre-drying sample as well. These two PFAS were still detected in post-drying samples, but their concentrations decreased. Average PFAS removal across the three samples was 76% (ESI†Table S13). These results indicate that drying can reduce measurable PFAS in biosolids, but drying does not completely remove PFAS from biosolids. 3.3. Impact of drying temperature on PFAS profiles in samples with high moisture content High moisture content samples (99.8%) were dried at 30 °C and 105 °C. Overall, the PFAS fingerprint and concentration profiles were similar for samples dried at 30 °C and samples dried at 105 °C (Fig. 5), but temperature did have some effect on PFAS profiles in the dried biosolids. Four of the eight PFAS detected in both post-drying samples across all tripli- cates (5:3 FTCA, 7:3 FTCA,N-methyl perfluorooctane sulfo- namido ethanol (NMeFOSE), and perfluorododecanoic acid (PFDoA)) were significantly lower in biosolids dried at 105 °C compared to biosolids dried at 30 °C (ESI†Tables S14–S16). Similar to the other data sets, 5:3 FTCA and PFOS were the first and second most abundant PFAS in every sample (Fig. 5 and ESI†Tables S14 & S15). Overall, the total PFAS concentra- tion was 16% lower in the 105 °C post-drying sample than the 30 °C post-drying sample, with a statistically significant p-value of 0.0058. A wipe kit was provided by Eurofins to wipe the drying tins and test for residual PFAS. The reporting limit was 1 ng PFAS per wipe. No PFAS detections were observed for any of the six wipes tested (three tins at each tempera- ture). Either there were no residual PFAS in the tins, or the wipes were not able to absorb residual PFAS that may have been left in the tins. This test was conducted to observe any major experimental artifacts of PFAS residual in tins that could be absorbed with a methanol wipe. 3.4. Impact of moisture content on PFAS removal Across the full-scale dryer and lab-scale oven data sets, mois- ture content was weakly correlated to total PFAS removal (Fig. 6, ESI†Table S18). The potential role of water in PFAS removal is discussed in more detail in the discussion section below. While certainly more data from a range of biosolids types and moisture contents are needed to validate this corre- lation, these data indicate that further study on the role of moisture content during drying of biosolids is warranted. Fig. 4 Lab-scale oven drying reduced measurable PFAS in samples from three different WRRFs. Reprinted with permission.©The Water Research Foundation. 39 Fig. 5 Drying at 105 °C decreased total PFAS concentration by 16% compared to drying at 30 °C. Water content of pre-drying solids was 99.8%. 30 °C and 105 °C drying of samples were conducted in tripli- cate (n = 3). Reprinted with permission.©The Water Research Foundation.39 Fig. 3 Average total PFAS concentration (normalized to μmol F kg -1) across pre-drying solids, lab-scale oven post-drying solids, and full- scale dryer post-drying solids. Samples taken in triplicate (n = 3) and error bars represent standard deviation. Reprinted with permission.© The Water Research Foundation. 39 Environmental Science: Water Research & Technology Paper Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 4. Discussion The effect of drying on the PFAS profile of biosolids has been largely overlooked in literature. 34 Due to the recognized ther- mal stability of PFAS and their high boiling points as pure substances, it has been posited that temperatures around 100 °C would be insufficient to remove them from biosolids. 33 The following three sections discuss possibilities to explain the observed PFAS removal with recognition that more re- search is required to determine the removal mechanism. 4.1. Potential role of water and removal with aerosols It has been established that PFAS readily partition to the air– water interface (AWI), and, in fact, a reduction in the aque- ous concentration of PFAS increases this tendency of PFAS to partition to the AWI. 41–43 In the case of water-bearing bio- solids, an accurate assessment of the AWI partitioning ten- dency of PFAS is complicated by the potential presence of air bubbles formed during the drying process as the temperature approaches 100 °C, at which point the water begins to boil. 44 As the boiling bubbles burst upon reaching the surrounding atmosphere of the biosolids, small water droplets may be flung into the air in what is referred to as the “bubble micro- tome effect”; these droplets, having existed as underwater pockets of air before bursting, may harbor significant quanti- ties of PFAS that partitioned to their surface. 44 Furthermore, Hoff et al.suggest that the organic solutes most apt to parti- tion to the interface of air bubbles have low vapor pressure and low solubility in water, and are typically polar; with polar functional groups and low Henry's constants, this characteri- zation may apply to some PFAS, including PFAAs. 44,45 In this way, the drying of biosolids may provide an avenue by which non-volatile PFAS may escape wet biosolids,i.e.,via attach- ment to bubbles that form during drying and subsequent re- lease (and removal from biosolids) attributed to the bubble microtome effect. Additionally, recent research by Nguyen et al.revealed that PFAS can be removed from wastewater aeration basins via at- tachment to aerosols. 46 Indeed, PFOS removal was over 75%, and the concentration of PFOS associated with aerosols was 100 to 1000-fold greater than the PFOS associated with the wastewater.46 PFOA also exhibited similar removal via associ- ation with aerosols. 46 This finding is important for two rea- sons. First, the removal of PFAS to aerosols occurred at 20 °C, a temperature well below the boiling point of water as well as lower than the temperatures reported for volatiliza- tion of PFAS, indicating that it is possible for PFAS to leave a water matrix without volatilizing. 46–50 Second, the PFAS that were removed via association to aerosols were not classically defined ‘volatile’PFAS,e.g., fluorotelomer alcohols (FTOH), that have been reported in landfill gas, for example. 45,51 Therefore, this aerosol removal mechanism does not require a phase change of PFAS. As the agitation of water due to aera- tion within aeration basins may catalyze the aerosolization of water, the tendency of PFAS to partition to the AWI may in- crease their susceptibility to removal with these water mole- cules.43,52 This phenomenon of aerosolization of PFAS could also likely occur during tumbling of biosolids in rotary dryers. In addition to these more nuanced potential mechanisms of removal, Hakeem et al.highlighted the need for more re- search to understand the impact of water vaporization on the fate of PFAS during the drying of biosolids; due to the com- plexity of interactions at the AWI, it may also be prudent to explore the impact of water content on removal. 33 As the PFAS concentration in the drying biosolids decreases, their tendency to partition to the AWI may increase, which may perpetuate the cycle of their removal during the above pro- cesses, despite the fact that they may occur at temperatures lower than the PFAS' boiling points. 43,47–50 In order to vali- date this claim, an analysis of the atmospheres of the drying environments (both lab-scale ovens and full-scale dryers), as well as of any water droplets generated and expelled during heating processes would be necessary. 45,53 Moreover, varia- tions in moisture content may affect the consistency of PFAS extraction methods from solid samples due to the complex partitioning behavior of PFAS in multi-phase media. Further investigation on extraction methods and experimental arti- facts is prudent for understanding the entire scope of the ob- served results. 4.2. Potential role of pure chemical volatilization While PFAS are used in non-stick pans and fire-fighting foams because of their resistance to degradation, they still can volatil- ize as temperatures increase. 49 Sasi et al.observed PFOA weight loss at 100 °C via thermal gravimetric analysis (TGA), raising the possibility that some PFOA could be lost during drying via vola- tilization.49 However,inthepurechemicalstudiesbySasiet al., PFOS weight loss was not observed until temperatures were Fig. 6 Moisture content correlated to PFAS removal across sample sets. Reprinted with permission.©The Water Research Foundation. 39 Environmental Science: Water Research & TechnologyPaper Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 above 400 °C.54 The drying temperatures in these studies were below 400 °C, yet PFOS removal was still observed, indicating that loss via volatilization was unlikely, or at the least not the major removal mechanism. 49,54 4.3. Potential role of biotransformation In addition to the concentration of PFAS changing during dry- ing, the fingerprint,i.e.the specific PFAS present in each sam- ple, changed after drying. FTCAs are a common class of precur- sors, and it is possible that biological enzymes converted FTCA precursors to terminal short-chain PFAAs such as perfluorobutanoic acid (PFBA), PFPeA, or PFHxA. 55 Research has been reported on the degradation of 5:3 FTCA to PFPeA and the more general theory that n :2 fluorotelomer carboxylic acids,N-alkyl perfluoroalkane sulfonamido acetic acids, and perfluoroalkane sulfonamido ethanols (i.e.6:2 FTCA, NEtFOSAA, NMeFOSAA, and NMeFOSE) transform into perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sul- fonic acids (PFSAs). 35–37 The fraction of total PFAS attributed to precursors decreased after drying for the majority of experi- ments (ESI†Fig. S2). To confirm biotransformation, microbial activity assays and microbial community analyses would need to be conducted. If transformation were the only mechanism oc- curring, then total targeted PFAS measurements would increase as undetectable precursors were converted to detectable termi- nal species. The total sum of PFAS went down, implying that other mechanisms are at play even if transformation partially explained a change in PFAS profiles. 5. Conclusions Biosolids management plans that incorporate PFAS manage- ment considerations are imperative while regulatory agencies weigh risk assessments for allowable PFAS concentrations that are safe for land application of biosolids. Source reduc- tion is still the most important and effective way to mitigate PFAS in wastewater solids. It is essential to recognize the im- pact that all treatment processes may have on altering the PFAS profile of biosolids. Current treatment technologies could be leveraged to achieve compliance. Drying of biosolids may serve as a method by which PFAS contaminated bio- solids are treated and made to achieve regulatory compliance for land-application. However, it is essential to recognize that the reduction in concentration of PFAS in biosolids during drying might result in air-borne PFAS associated with water droplets. Additional studies are needed to assess the fate of PFAS to assist the industry and regulators in establishing ap- propriate management and treatment protocols. Both lab- scale oven drying and full-scale drying processes had signifi- cant impacts on the measurable PFAS profile of biosolids, thereby suggesting that drying is indeed an effective process for altering the PFAS profile of biosolids. Drying is a technol- ogy already widely used in the industry. While drying does not completely remove PFAS to below reporting limits, it does substantially reduce measurable PFAS concentrations. Future research is needed to confirm if PFAS are emitted with the gas phase or if other mechanisms are responsible for these changes observed during drying. Data availability The data supporting this article have been included as part of the ESI.† Conflicts of interest There are no conflicts to declare. Acknowledgements This research was funded by the Water Research Foundation Project 5211 as well as the Black & Veatch Innovation Platform. References 1 C. E. Schaefer, J. L. Hooper and L. E. Strom,et al. Occurrence of quantifiable and semi-quantifiable poly- and perfluoroalkyl substances in united states wastewater treat- ment plants,Water Res., 2023,233,1–10, DOI:10.1016/j. watres.2023.119724. 2 J. L. Guelfo, S. Korzeniowski and M. A. Mills,et al. Environmental Sources, Chemistry, Fate, and Transport of Per- and Polyfluoroalkyl Substances: State of the Science, Key Knowledge Gaps, and Recommendations Presented at the August 2019 SETAC Focus Topic Meeting,Society of Environ- mental Toxicology and Chemistry, 2021,40(12), 3234–3260, DOI:10.1002/etc.5182. 3 H. N. P. Vo, H. H. Ngo and W. Guo,et al.Poly- and perfluoroalkyl substances in water and wastewater: A com- prehensive review from sources to remediation,J. Water Pro- cess Eng., 2020,36,1–21, DOI:10.1016/j.jwpe.2020.101393. 4 R. Mueller and K. E. Schlosser, History and Use of Per- and Polyfluoroalkyl Substances (PFAS) found in the Environment, PFAS Fact Sheets, 2020, 1–4,https://pfas-1.itrcweb.org/. 5 S. A. O. De, J. M. Armitage and T. A. Bruton,et al.PFAS Exposure Pathways for Humans and Wildlife: A Synthesis of Current Knowledge and Key Gaps in Understanding,Society of Environmental Toxicology and Chemistry, 2020,40(3), 631–657, DOI:10.1002/etc.4935. 6 H. Fromme, C. Mosch and M. Morovitz,et al.Pre- and Postna- tal Exposure to Perfluorinated Compounds (PFCs),Environ. Sci. Technol., 2010,44(18), 7123–7129, DOI:10.1021/es101184f. 7 T. Stahl, D. Mattern and H. Brunn, Toxicology of perfluorinated compounds,Environ. Sci. Eur., 2011,23(38), 1–52, DOI:10.1186/2190-4715-23-38. 8 R. R. Worley, S. M. A. Moore and B. C. Tierney,et al.Per- and polyfluoroalkyl substances in human serum and urine samples from a residentially exposed community,Environ. Int., 2017,106, 135–143, DOI:10.1016/j.envint.2017.06.007. 9 F.Sabba,C.Kassar,T.Zeng,S.P.Mallick,L.DowningandP. McNamara, PFAS in landfill leachate: Practical considerations for treatment and characterization,J. Hazard. Mater., 2025,481, 1–20, DOI:10.1016/j.jhazmat.2024.136685. Environmental Science: Water Research & Technology Paper Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 10 S. B. Gewurtz, A. S. Auyeung, A. O. De Silva, S. Teslic and S. A. Smyth, Per- and polyfluoroalkyl substances (PFAS) in Canadian municipal wastewater and biosolids: Recent patterns and time trends 2009 to 2021,Sci. Total Environ., 2024,912,1–11, DOI:10.1016/j.scitotenv.2023.168638. 11 X. C. Hu, D. Q. Andrews and A. B. Lindstrom,et al.Detection of Poly- and Perfluoroalkyl Substances (PFASs) in U.S. Drinking Water Linked to Industrial Sites, Military Fire Training Areas, and Wastewater Treatment Plants,Environ. Sci. Technol. Lett., 2016,3(10), 344–350, DOI:10.1021/acs.estlett.6b00260. 12 R.KimLazcano,C.dePerre,M.L.MashtareandL.S.Lee,Per- and polyfluoroalkyl substances in commercially available biosolid-based products: The effect of treatment processes,Water Environ. Res., 2019,91(12), 1669–1677, DOI:10.1002/wer.1174. 13 A. Garg, N. P. Shetti, S. Basu, M. N. Nadagouda and T. M. Aminabhavi, Treatment technologies for removal of per- and polyfluoroalkyl substances (PFAS) in biosolids,Chem. Eng. J., 2023,453(Part 2), 1–18, DOI:10.1016/j.cej.2022.139964. 14 H. Hall, D. Moodie and C. Vero, PFAS in biosolids: A review of international regulations,Water J., 2020,5(4), 41,https:// www.awa.asn.au/resources/latest-news/community/public- health/pfas-in-biosolids-a-review-of-international-regulations. 15 M. P. Vélez, T. E. Arbuckle and W. D. Fraser, Maternal exposure to perfluorinated chemicals and reduced fecundity: the MIREC study,Hum. Reprod., 2015,30(3), 701–709, DOI: 10.1093/humrep/deu350. 16 National Toxicology Program.NTP Monograph Immunotoxicity Associated with Exposure to Perfluorooctanoic Acid or Perfluorooctane Sulfonate;2016,https://ntp.niehs.nih.gov/go/ mgraph04. 17 M. Nannaware, N. Mayilswamy and B. Kandasubramanian, PFAS: exploration of neurotoxicity and environmental impact,Environ. Sci. Pollut. Res., 2024,31, 12815–12831, DOI: 10.1007/s11356-024-32082-x. 18 L. Anderko and E. Pennea, Exposures to per-and poly- fluoroalkyl substances (PFAS): Potential risks to reproduc- tive and children's health,Curr. Probl. Pediatr. Adolesc. Health Care, 2020,50(2), 1–4, DOI:10.1016/j. cppeds.2020.100760. 19 M. Mastrantonio, E. Bai, R. Uccelli, V. Cordiano, A. Screpanti and P. Crosignani, Drinking water contamination from perfluoroalkyl substances (PFAS): an ecological mortality study in the Veneto Region, Italy,Eur. J. Public Health, 2017,28(1), 180–185, DOI:10.1093/eurpub/ckx066. 20 T. D. Saliu and S. Sauvé, A review of per- and polyfluoroalkyl substances in biosolids: geographical distribution and regu- lations,Front. Environ. Chem., 2024,5,1–19, DOI:10.3389/ fenvc.2024.1383185. 21 L. J. Winchell, J. J. Ross, M. J. M. Wells, X. Fonoll, J. W. Norton and K. Y. Bell, Per- and polyfluoroalkyl substances thermal destruction at water resource recovery facilities: A state of the science review,Water Environ. Res., 2021,93(6), 826–843, DOI:10.1002/wer.1483. 22 A. Alinezhad, P. Challa Sasi and P. Zhang,et al.An Investigation of Thermal Air Degradation and Pyrolysis of Per- and Polyfluoroalkyl Substances and Aqueous Film- Forming Foams in Soil,ACS ES&T Eng., 2022,2(2), 198–209, DOI:10.1021/acsestengg.1c00335. 23 P. McNamara, Z. Liu, Y. Tong, H. Santha, L. Moss and D. Zitomer, Pyrolysis—A tool in the wastewater solids handling portfolio, not a silver bullet: Benefits, drawbacks, and future directions,Water Environ. Res., 2023,95(5), 1–14, DOI: 10.1002/wer.10863. 24 E. D. Thoma, R. S. Wright and I. George,et al.Pyrolysis processing of PFAS-impacted biosolids, a pilot study,J. Air Waste Manage. Assoc., 2022,72(4), 309–318, DOI:10.1080/ 10962247.2021.2009935. 25 L. J. Winchell, J. Cullen and J. J. Ross,et al.Fate of biosolids-bound PFAS through pyrolysis coupled with ther- mal oxidation for air emissions control,Water Environ. Res., 2024,96(11), 1–13, DOI:10.1002/wer.11149. 26 P. McNamara, M. S. Samuel and S. Sathyamoorthy,et al. Pyrolysis transports, and transforms, PFAS from biosolids to py-liquid,J. Environ. Sci., 2022,9(2), 386–395, DOI:10.1039/ d2ew00677d. 27 J. Wang, M. Song, I. Abusallout and D. Hanigan, Thermal Decomposition of Two Gaseous Perfluorocarboxylic Acids: Products and Mechanisms,Environ. Sci. Technol., 2023,57(15), 6179–6187, DOI:10.1021/acs.est.2c08210. 28 J. Wang, Z. Lin and X. He,et al.Critical Review of Thermal Decomposition of Per- and Polyfluoroalkyl Substances: Mechanisms and Implications for Thermal Treatment Pro- cesses,Environ. Sci. Technol., 2022,56(9), 5355–5370, DOI: 10.1021/acs.est.2c02251. 29 T. Williams, S. Grieco, B. Bani, A. Friedenthal and A. White, Residuals and Biosolids 2021, In:Removal and Transformation of PFAS from Biosolids in a High Temperature Pyrolysis System - A Bench Scale Evaluation, Water Environment Federation, 2021, DOI:10.2175/193864718825157943. 30 L. J. Winchell, M. J. M. Wells and J. J. Ross,et al.Fate of perfluoroalkyl and polyfluoroalkyl substances (PFAS) through two full-scale wastewater sludge incinerators, Water Environ. Res., 2024,96(3), 1–28, DOI:10.1002/ wer.11009. 31 L. J. Winchell, J. J. Ross and D. A. Brose,et al.High- temperature technology survey and comparison among in- cineration, pyrolysis, and gasification systems for water re- source recovery facilities,Water Environ. Res., 2022,94(4), 1–18, DOI:10.1002/wer.10715. 32 J. T. Thompson, N. M. Robey, T. M. Tolaymat, J. A. Bowden, H. M. Solo-Gabriele and T. G. Townsend, Underestimation of PFAS during conventional treatment,Environ. Sci. Technol., 2023,57(9), 3825–3832, DOI:10.1021/acs.est.2c06189. 33 I. G. Hakeem, P. Halder and S. Patel,et al.Current understanding on the transformation and fate of per- and polyfluoroalkyl substances before, during, and after thermal treatment of biosolids,Chem. Eng. J., 2024,493,1–28, DOI: 10.1016/j.cej.2024.152537. 34 J. Ross, A. Seidel, L. Winchell, M. Wells and D. Song, Residuals and Biosolids 2024, In:PFAS Assessment of a Rotary Drum Dryer, Water Environment Federation, 2024, DOI: 10.2175/193864718825159466. Environmental Science: Water Research & TechnologyPaper Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online Environ. Sci.: Water Res. Technol.This journal is © The Royal Society of Chemistry 2025 35 U. Eriksson, P. Haglund and A. Kärrman, Contribution of precursor compounds to the release of per- and poly- fluoroalkyl substances (PFASs) from waste water treatment plants (WWTPs),J. Environ. Sci., 2017,61,80–90, DOI: 10.1016/j.jes.2017.05.004. 36 Z. Wang, J. C. Dewitt, C. P. Higgins and I. T. Cousins, A Never-Ending Story of Per- and Polyfluoroalkyl Substances (PFASs)?,Environ. Sci. Technol., 2017,51(5), 2508–2518, DOI: 10.1021/acs.est.6b04806. 37 R. C. Buck, J. Franklin and U. Berger,et al. Perfluoroalkyl and polyfluoroalkyl substances in the environment: Terminology, classification, and origins, Integr. Environ. Assess. Manag., 2011,7(4), 513–541, DOI: 10.1002/ieam.258. 38 K. E. Miller and M. J. Strynar, Improved Tandem Mass Spectrometry Detection and Resolution of Low Molecular Weight Perfluoroalkyl Ether Carboxylic Acid Isomers, Environ. Sci. Technol. Lett., 2022,9(9), 747–751, DOI:10.1021/ acs.estlett.2c00509. 39 P. McNamara, G. Knight, T. McKnight and Z. Liu, Understanding the Value Proposition for Thermal Processes to Mitigate PFAS in Biosolids, The Water Research Foundation, Project 5211, Final Report Forthcoming (anticipated 2026). 40 Minnesota Pollution Control Agency,Minnesota Biosolids PFAS Strategy, 2025,https://www.pca.state.mn.us/sites/ default/files/wq-wwprm2-113a.pdf. 41 Y. Kim, K. A. Pike, R. Gray, J. W. Sprankle, J. A. Faust and P. L. Edmiston, Non-targeted identification and semi- quantitation of emerging per-and polyfluoroalkyl substances (PFAS) in US rainwater,Environ. Sci.: Process. Impacts, 2023,25(11), 1771–1787, DOI:10.1039/D2EM00349J. 42 C. E. Schaefer, M. C. S. Lemes, T. Schwichtenberg and J. A. Field, Enrichment of poly- and perfluoroalkyl substances (PFAS) in the surface microlayer and foam in synthetic and natural waters,J. Hazard. Mater., 2022,440,1–7, DOI: 10.1016/j.jhazmat.2022.129782. 43 C. E. Schaefer, V. Culina, D. Nguyen and J. Field, Uptake of Poly- And Perfluoroalkyl Substances at the Air-Water Inter- face,Environ. Sci. Technol., 2019,53(21), 12442–12448, DOI: 10.1021/acs.est.9b04008. 44 J. T. Hoff, D. Mackay, R. Gillham and W. Y. Shiu, Partitioning of Organic Chemicals at the Air-Water Interface in Environmental Systems,Environ. Sci. Technol., 1993,27(10), 2174–2180, DOI:10.1021/es00047a026. 45 I. Abusallout, C. Holton, J. Wang and D. Hanigan, Henry's Law constants of 15 per- and polyfluoroalkyl substances de- termined by static headspace analysis,J. Hazard. Mater. Lett., 2022,3,1–6, DOI:10.1016/j.hazl.2022.100070. 46 D. Nguyen, J. Stults and J. Devon,et al.Removal of per- and polyfluoroalkyl substances from wastewater via aerosol cap- ture,J. Hazard. Mater., 2024,465,1–9, DOI:10.1016/j. jhazmat.2024.133460. 47 F. Xiao, P. Challa Sasi, A. Alinezhad, R. Sun and A. M. Abdulmalik, Thermal Phase Transition and Rapid Degradation of Forever Chemicals (PFAS) in Spent Media Using Induction Heating,ACS ES&T Eng., 2023,3(9), 1370–1380, DOI:10.1021/acsestengg.3c00114. 48 E.Gagliano,M.Sgroi,P.P.Falciglia,F.G.A.VagliasindiandP. Roccaro, Removal of poly- and perfluoroalkyl substances (PFAS) from water by adsorption: Role of PFAS chain length, effect of organic matter and challenges in adsorbent regeneration,Water Res., 2020,171,1–31, DOI:10.1016/j.watres.2019.115381. 49 F. Xiao, P. C. Sasi and B. Yao,et al.Thermal Stability and Decomposition of Perfluoroalkyl Substances on Spent Granular Activated Carbon,Environ. Sci. Technol. Lett., 2020,7(5), 343–350, DOI:10.1021/acs.estlett.0c00114. 50 P. C. Sasi, A. Alinezhad and B. Yao,et al.Effect of granular activated carbon and other porous materials on thermal decomposition of per- and polyfluoroalkyl substances: Mech- anisms and implications for water purification,Water Res., 2021,200,1–10, DOI:10.1016/j.watres.2021.117271. 51 A. M. Lin, J. T. Thompson, J. P. Koelmel, Y. Liu, J. A. Bowden and T. G. Townsend, Landfill Gas: A Major Pathway for Neutral Per- and Polyfluoroalkyl Substance (PFAS) Release, Environ. Sci. Technol. Lett., 2024,11(7), 730–737, DOI: 10.1021/acs.estlett.4c00364. 52 Y. Han, T. Yang, X. Yan, L. Li and J. Liu, Effect of aeration mode on aerosol characteristics from the same wastewater treatment plant,Water Res., 2020,170,1–11, DOI:10.1016/j. watres.2019.115324. 53 H. Hayes, C. Lutes and N. Watson,et al.Laboratory development and validation of vapor phase PFAS methods for soil gas, sewer gas, and indoor air,Environ. Sci.: Atmos., 2024,5,94–109, DOI:10.1039/d4ea00084f. 54 P. C. Sasi, A. Alinezhad, B. Yao, A. Kubátová, S. A. Golovko, M. Y. Golovko and F. Xiao,et al.Effect of granular activated carbon and other porous materials on thermal decomposi- tion of per- and polyfluoroalkyl substances: Mechanisms and implications for water purification,Water Res., 2021,200, 117271, DOI:10.1016/j.watres.2021.117271. 55 F. Chi, J. Zhao and L. Yang,et al.Using regular and transcriptomic analyses to investigate the biotransformation mechanism and phytotoxic effects of 6:2 fluorotelomer carboxylic acid (6,2 FTCA) in pumpkin (Cucurbita maxima L.),Sci. Total Environ., 2024,906,1–9, DOI:10.1016/j. scitotenv.2023.167901. Environmental Science: Water Research & Technology Paper Open Access Article. Published on 07 March 2025. Downloaded on 3/18/2025 2:35:46 PM. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.View Article Online 70 From:Peter Hague <phague@co.slo.ca.us> Sent:Friday, February 28, 2025 8:42 AM To:agriffith@cityofsantamaria.org; Lehman, Chris; Mladen Bandov; Damaris Hanson; Casey Shepherd; Ryan Hayes Subject:Land Application of Biosolids Lit Review Attachments:Env Health Risks from Biosolids, Pozzebon and Siefert.pdf This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Hello all It was a pleasure to meet you all yesterday. Here is the literature review of land applicaƟon of biosolids prepared by the past directors of SLO and SB County Env Health. 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The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Pozzebon and Seifert Environmental Health (2023) 22:57 https://doi.org/10.1186/s12940-023-01008-4 Environmental Health *Correspondence: Lars Seifert LSeifert@sbcphd.org 1California Conference of Directors of Environmental Health, P.O. Box 2017, Cameron Park, CA 95682-2017, USA Abstract Background Over 40% of the six million dry metric tons of sewage sludge, often referred to as biosolids, produced annually in the United States is land applied. Biosolids serve as a sink for emerging pollutants which can be toxic and persist in the environment, yet their fate after land application and their impacts on human health have not been well studied. These gaps in our understanding are exacerbated by the absence of systematic monitoring programs and defined standards for human health protection. Methods The purpose of this paper is to call critical attention to the knowledge gaps that currently exist regarding emerging pollutants in biosolids and to underscore the need for evidence-based testing standards and regulatory frameworks for human health protection when biosolids are land applied. A scoping review methodology was used to identify research conducted within the last decade, current regulatory standards, and government publications regarding emerging pollutants in land applied biosolids. Results Current research indicates that persistent organic compounds, or emerging pollutants, found in pharmaceuticals and personal care products, microplastics, and per- and polyfluoroalkyl substances (PFAS) have the potential to contaminate ground and surface water, and the uptake of these substances from soil amended by the land application of biosolids can result in contamination of food sources. Advanced technologies to remove these contaminants from wastewater treatment plant influent, effluent, and biosolids destined for land application along with tools to detect and quantify emerging pollutants are critical for human health protection. Conclusions To address these current risks, there needs to be a significant investment in ongoing research and infrastructure support for advancements in wastewater treatment; expanded manufacture and use of sustainable products; increased public communication of the risks associated with overuse of pharmaceuticals and plastics; and development and implementation of regulations that are protective of health and the environment. Keywords Biosolids, Emerging pollutants, Land application, Microplastics, Organic contaminants, Per-and polyfluorinated alkyl substances (PFAS), Pharmaceutical and personal care products (PPCPs) Emerging environmental health risks associated with the land application of biosolids: a scoping review Elizabeth A. Pozzebon1 and Lars Seifert1* Page 2 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 Background During wastewater treatment, solids are separated from liquids and are then treated physically and chemically to produce a semisolid, nutrient-rich product known as biosolids or sewage sludge. Biosolids are typically dis- posed of through landfilling, incineration, or are used as a soil amendment (fertilizer) as they contain high con- centrations of nitrogen, phosphorous, organic carbon, and other essential elements which are beneficial for soil quality and crop production [1–3]. Although the benefit of recycling nutrients necessary for crop production and avoiding the use of energy-intensive synthetic fertiliz- ers is significant, biosolids also act as a sink for emerg- ing pollutants [3–21]. Preventing harmful exposures to these emerging pollutants when land applied remains a challenge [10, 20, 22]. The debate over safely using these human waste-derived biosolids as soil amendments is ongoing [23]. The US EPA standards for determining biosolids qual- ity are found in Title 40 of the Code of Federal Regula- tions, Part 503, but are limited in focus to the presence of ten inorganic metals (As, Cd, Cu, Hg, Mo, Ni, Pb, Cr, Se, and Zn), pathogens, and vector attractiveness. These standards do not currently contain regulatory standards or thresholds that pertain to the presence of synthetic organic contaminants [10]. And, while many organic compounds degrade easily and have minimal harmful effects on the environment, other more toxic organic contaminants meet the US EPA’s definition of being persistent and can accumulate in environment, causing harm to humans and wildlife when land applied [24]. In addition to the lack of standards for monitoring persis- tent and toxic organic contaminants in biosolids prior to land application, there are significant gaps in our under- standing of fate of these pollutants once land applied and the synergistic effects of multiple organic compounds on their distribution and transport within the environment. Moreover, the lack of efficient technologies to detect and measure these organic contaminants further reduces our ability to monitor their presence in the environment and evaluate potential impacts on human health. The volume of biosolids produced in the US is not inconsequential. The US EPA estimates that, in states where they are the permitting authority, 4.5 million dry metric tons were produced in 2021 with nearly half (43%) being land applied [25]. The remaining biosolids were landfilled, incinerated, or managed by other methods such as storage or deep well injection. The US EPA also notes that the actual amount produced could be as much as 6 million dry metric tons according to a 2018 survey conducted by the North East Biosolids and Residuals Association, because it additionally accounts for states where US EPA is not the permitting authority. The global market for biosolids was estimated at 7.5 billion USD in 2022 and is projected to reach 10.7 billion USD by 2030 [26]. This scoping review provides a landscape of the current research regarding emerging pollutants in biosolids and their fate in the environment when land applied. Poten- tial pathways of exposure, current detection methods, and possible impacts on human health and the environ- ment are discussed. The need for additional research on the fate of these pollutants and their synergistic effects in the environment along with the significant need for novel treatment methods and detection technologies for emerging pollutants is highlighted. The authors call criti- cal attention to the many knowledge gaps that currently exist to guide state and Federal regulatory frameworks for human health protection when biosolids are land applied. Methods We used an iterative process to select academic and governmental publications for inclusion in this scop- ing review. Initially, we searched databases and govern- mental websites to identify publications associated with risks to human health and the environment from the land application of biosolids using the following terms com- bined with “biosolids” or “land application of biosolids”: contaminants; organic contaminants; emerging pollut- ants; PFAS; microplastics; ground water; surface water; plant uptake; wildlife; agriculture; health risk; benefits of; pharmaceutical; personal care products; antibiotic; endo- crine disrupter; treatment technology; diagnostic tech- niques; regulations; and fate and transport. Publications were initially screened for relevance using the title and/ or abstract, and those relevant to biosolids land applica- tion were reviewed in their entirety. Authors identified through the literature search were contacted for further discussion regarding their study findings and were asked for suggestions on additional publications or resources for inclusion. References from identified publications’ citation lists were also reviewed to identify other appli- cable resources. A concerted effort was made to establish an exhaustive list of studies that were published in the last decade (between 2011 and 2022) pertaining to the land application of biosolids. Results A total of 172 scholarly research articles and governmen- tal reports were included in this scoping review (Supple- mental Fig. 1). Biosolids contain nutrients and energy which can be used in agriculture or waste-to-energy pro- cesses [11] or to replenish organic carbon in soils. How- ever, while they do contain valuable nutrients (mostly nitrogen and phosphorus), they also contain a range of synthetic organic compounds. These organic com- pounds are produced for a variety of purposes, including Page 3 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 healthcare, agriculture, and transportation, and are con- sidered indispensable for modern society [27–29]. While many organic compounds degrade easily and have mini- mal harmful effects on the environment, other more per- sistent synthetic organic contaminants have the potential to accumulate in biological matrices and can eventually cause harm to humans, wildlife, and the environment [24, 30]. Conventional wastewater treatment plants were not designed to remove these emerging pollutants and currently they are only partially effective in removing or degrading synthetic organic compounds [22, 31] result- ing in the accumulation of these pollutants in biosolids. While the risk of direct human exposure to emerging pollutants in biosolids is low and realistically may involve only those who work with biosolids such as farmers and biosolids workers [32], the risk of indirect exposure is significantly higher. Not only can the land application of biosolids result in ingestion of contaminated food-crops, animal up-take in meat or milk, and drinking water con- tamination, but it can also lead to pollutant exposure via inhalation [14, 19, 32–36]. Although exposure to indi- vidual synthetic organic pollutants in biosolids such as antimicrobials, pharmaceuticals, personal care products, surfactants and hormones would not accumulate in the food chain at concentrations that may pose a risk for human health, the sum of them could be of considerable concern [11, 37]. In this review we focus on three broad classes of emerging pollutants that pose the most significant risks to human and environmental health when biosolids are land applied to agricultural soils. Then, we explore the fate, transport, and synergistic effects of these emerging pollutants generally in the environment. Finally, we dis- cuss current diagnostic tools, treatment methods and the critical need for the development of standards to protect human and environmental health. Emerging pollutants Microplastics Microplastics, plastic pieces less than five millimeters in diameter, are typically the result of larger plastic debris degrading into smaller sizes; however some microplas- tics, such as microbeads, are manufactured at micro sizes and are often used in commercial health and beauty products [38]. Microplastics easily pass through waste- water treatment systems and approximately 70 to 98% of microplastics from liquid wastewater accumulate in bio- solids during the treatment process [20, 39–41]. Unsurprisingly, the land application of biosolids has led to agricultural soils being one of the largest natural res- ervoirs of microplastics [20]. Corradini et al. [13] evalu- ated 31 agricultural fields and found that concentration of microplastics in agricultural soils increased over time after successive land applications of biosolids. Soils with 1, 2, 3, 4, and 5 applications of biosolids had medians of 1.1, 1.6, 1.7, 2.3, and 3.5 particles g− 1 dry soil, respec- tively, demonstrating that microplastic concentrations were significantly correlated with biosolids applications. In addition, microplastics from land applied biosolids do not always remain in the soil but can also be released into the surrounding environment [3, 5]. Although the true scale of microplastic contamination has yet to be assessed, studies have repeatedly detected microplas- tics at significant distances from their source of origin and at higher elevations, indicating their susceptibility to becoming airborne [3, 42–46]. Inhalation of micro- plastics is associated with oxidative stress in lung tissues, along with general inflammatory responses in airways and bronchi and chronic exposure can lead to death [3, 47, 48]. Several other studies have also directly mea- sured microplastic concentrations suspended in air or dust, [49–52] deposited on land, [53, 54] or trapped on tree canopies [3, 55]. And because the impact of the hori- zontal and vertical intra- and inter-ecosystem spread of microplastics in the environment remains unquantified on the whole ecosystem [56], and ultimately on humans via the food chain, this area needs further investigation, particularly because microplastics are persistent in the environment and can accumulate in soil [3, 20, 57, 58]. Per- and polyfluorinated alkyl substances (PFAS) Per- and Polyfluorinated Alkyl Substances (PFAS) is a broad term for manmade aliphatic compounds with at least one carbon-fluorine (C-F) bond [14, 59]. PFAS have been mass produced since the 1940s [14, 59]; how- ever, due to environmental concerns, the production and use of long-chain (≥ 8 carbons) PFAS in North America, Europe, and Australia were voluntarily phased out in the early 2000s and replaced with shorter-chain PFAS [59, 60]. Short-chained PFAS have a lower tendency to be absorbed or leached into the soil and bioaccumulate, but are also more mobile in the environment than the lon- ger chain (C8) compounds [19, 59, 61] increasing risks of groundwater contamination and human exposure. Short- chain PFAS replacements also still persist in the environ- ment and can have adverse health and environmental effects [62–64]. A study measuring perfluoroalkyl carboxylic acid (PFCA), a subset of PFAS, in biosolids from multiple wastewater treatment plants in the US, Canada, Austra- lia, and Spain found that biosolids in the US have sig- nificantly higher amounts of PFCA compared to other countries [3]. This difference could be due to the con- tinued use of PFAS precursors in domestic and indus- trial products in the US or more sensitive methods used to detect PFAS in the reported study [3, 65]. Neverthe- less, PFAS concentrations in biosolids in the US have not Page 4 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 decreased even after long-chain PFAS use was phased out in the early 2000s [3, 10, 66]. The transformation of PFAS during wastewater treat- ment processing is of particular concern. A statewide assessment of PFAS in Michigan found that wastewa- ter industrial pretreatment programs were unable to break the C-F bond and instead transformed polyfluori- nated precursors to Perfluoroalkyl Acids (PFAAs) which are highly resistant to further degradation, effectively increasing effluent concentrations of total PFAS [14]. The stability of PFAAs, most notably perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), has earned PFAS the moniker “forever chemicals” [67, 68]. In addition to being considered a ‘forever chemical’ the fate of PFAS after being land applied is alarming. One of the earliest studies on PFAS in soil following the land application of biosolids found trace levels of perfluo- rochemicals in soil cores from biosolids-amended soils to depths of 120 cm, suggesting potential movement of these compounds within the soil profile over time [19]. A more recent study [17], investigating the impact of land applying biosolids on the occurrence, concentration, and distribution of PFAS in soils, the vadose zone, and groundwater detected PFAS in all near surface soil sam- ples (< 30 cm below ground surface), in more than 83% of soils between 30 and 90 cm below ground surface, and in the immediately underlying groundwater. PFAS, how- ever, were not detected in adjacent irrigation ditch soil samples where biosolids were not land applied. Like microplastics, PFAS have been detected in the remotest areas on earth [14, 67, 69] and high concen- trations of both microplastics and PFAS have even been detected in dust samples [52, 70]. The persistence of PFAS, with a half-life exceeding several decades, leads to complex cycling in the atmosphere, biosphere, geo- sphere, and hydrosphere (Fig. 1) further raising concerns regarding their ubiquitous distribution into human expo- sure pathways [3, 58, 71–73]. PFAS can cause adverse health impacts even at ultra- low concentrations, and have been found to bioaccumu- late in animals and humans in lung, kidney, liver, brain, and bone tissue [14, 74–82]. According to The California Department of Toxic Substances Control’s recently pub- lished chemical profile for PFAS, “Product – Chemical Profile for Treatments Containing Perfluoroalkyl or Poly- fluoroalkyl Substances for Use on Converted Textiles or Leathers” (February 2021 Final Version), PFAS exposure is associated with reproductive and developmental, liver and kidney, and immunological effects, as well as tumors in laboratory animals. In addition, inhalation of PFAS can cause acute lung toxicity and inhibit lung surfactant func- tion [3, 83, 84]. The most consistent finding from human epidemiology studies is the increase in serum cholesterol levels among exposed populations. Additionally, there are limited findings correlating exposure to infant birth weights, immune system dysfunction, cancer, and thyroid hormone disruption, and PFAS have also been linked to phytotoxicity, aquatic toxicity, and terrestrial ecotoxic- ity [84]. The Centers for Disease Control and Prevention (CDC), which monitors Americans’ exposure to PFAS as part of the National Health and Nutrition Examina- tion Survey, has detected PFAS in the blood of all people tested and notes that nearly all humans show evidence of exposure [85]. However, despite this universal exposure Fig. 1 PFAS cycle diagram depicting the movement of PFAS in natural and engineered systems [14] Page 5 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 and the potential adverse impacts to human health, there is a major data gap in our understanding of the relation- ship between exposure levels and toxicological outcomes, particularly for PFAS classes other than PFOA and PFOS [86]. The extent of environmental PFAS contamination is also not well quantified; however, based on the usage of biosolids reported by the US EPA and other study esti- mates, 1760 kg or more of PFAS could be annually depos- ited onto land directly via land application, from where they could spread into the environment via stormwater runoff, wind, and infiltration into ground water supplies [3, 10, 87]. Pharmaceuticals and personal care products Pharmaceutical and personal care products (PPCPs) are used by consumers for health and cosmetic purposes and by agroindustry to enhance the growth or health of livestock [88–90]. While not all PPCPs are persistent, many are considered “pseudo-persistent” because even though they have high transformation/removal rates this is offset by their continuous use and introduction into the environment [32, 91]. Traditional wastewater treatment plants are unable to effectively remove PPCPs [90, 92] and they can persist through wastewater treatment pro- cesses [12, 93–98]. Studies investigating the occurrence and distribution of pharmaceuticals in biosolids follow- ing wastewater treatment indicate that pharmaceuticals find their way into the environment mainly through the land spreading of biosolids [32, 99–102]. PPCPs contain chemicals that can disrupt endocrine functions and antibiotics that can lead to acquisition and spread of antibiotic resistance [12, 103]. The potential for reproductive failure caused by endocrine disrupting compounds in aquatic ecosystems (e.g., fathead min- nows, zebra fish and white sucker fish) has been exten- sively documented [12, 104–108]. However, the exposure, toxicity, and bioaccumulation of endocrine disruption compounds in terrestrial organisms has been less well studied. Preliminary evidence has suggested potential risks that are similar to those observed in aquatic species and these compounds have been implicated as potential contributors to diabetes, cancer, fertility decline, and a host of other environmental and public health issues [12]. Ultra-low nanogram per liter (ng/L) concentra- tions have exhibited impacts to both humans and aquatic organisms, including hormonal interference in fishes, genotoxicity, carcinogenicity in lab animals, endocrine disruption, and immune toxicity [29, 109, 110]. A recent nontargeted analysis using high-resolution mass spectrometry with predictive estrogenic activ- ity modeling was performed on biosolids samples from wastewater treatment plants in California to identify compounds in biosolids that present the most significant environmental barriers to its beneficial use as a soil amendment [23]. The study found that the combina- tion of predictive and in vitro estrogenicity with non- targeted analysis led to confirmation of estrogen-active contaminants in California biosolids and highlighted the importance of evaluating both agonistic and antagonis- tic responses when evaluating the bioactivity of complex samples. While these findings are compelling, it should be noted that the full spectrum of chemicals that have estrogenic activity and/or can affect the estrogen recep- tor signaling pathway and subsequent downstream physi- ological events remains largely unexplored [23]. According to the World Health Organization, the big- gest threat to global health, food security, and devel- opment is antibiotic resistance, of which PPCPs are a contributor. An increasing number of infections and diseases are becoming difficult to treat, as antibiotics used to treat them become less effective [29, 111, 112]. Our ability to effectively treat infections is hindered by the proliferation of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB), which encode various mechanisms conferring drug resistance [15]. A study by Law et al. (2021) found that the spread of ARGs among bacteria is largely driven by the horizontal trans- fer of mobile genetic elements (MGEs) such as plasmids (Fig. 2) [18]. And they indicate that plasmids are impor- tant vectors of horizontal gene transfer and are capable of transferring multiple ARGs simultaneously, provid- ing multidrug resistance to the recipient bacteria in one event. Enrichment of soils with ARGs following the appli- cation of biosolids has also been reported [8, 113–115] and given the frequent use of biosolids as fertilizer, their ability to actively transfer resistance genes to pathogens by means of these plasmids is concerning and needs to be further investigated [18]. Wolters et al. [116] also found that disinfectants, heavy metals (including Arsenic as a metalloid), and antibiotics can enhance horizontal gene transfer at sub-inhibitory concentrations. The authors of this study also indicate that use of biosolids as organic fertilizer is contentious – on the one hand, they pro- vide valuable fertilization while on the other they intro- duce pollutants that likely affect the soil resistome and increase transferability of ARGs, reinforcing the need for further investigation. A study by Sherburne et al. (2016) also found con- centrations of Triclocarban (TCC) and Triclosan (TCS) measured in each trophic level of a terrestrial food web at an agricultural field that had biosolids land applied over a seven-year period. The study investigated a terres- trial food web encompassing biosolids, soil, earthworms (primary consumer), deer mice (Peromyscus manicula- tus, secondary consumer), European starlings (Sturnus vulgaris, a secondary consumer of invertebrates), and American kestrels (Falco sparverius, a tertiary consumer Page 6 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 of rodents, small birds, and invertebrates) at the biosolids experimental site. The results were compared to the same type of sample results obtained from another agricultural reference site that did not have biosolids land applied and found that antimicrobials were detected in soil as well as in primary (earthworms), secondary (deer mice, star- lings), and tertiary (kestrels) consumers. Moreover, con- centrations were higher in biosolids (TCC − 1026 − 1472 ng/g wet weight (ww) and TCS − 1114 − 1350 ng/g ww), soil (TCC 14.8 − 27.3 ng/g ww and TCS − 2.7 − 4.4 ng/g ww), deer mice livers (TCC: 12.6 − 33.3 ng/g ww), and starling eggs (TCC: 15.4 − 31.4 ng/g ww) at the experi- mental site than at the reference site. Furthermore, a recent study by Hung et al. [15], found that the biosolid samples contained significantly higher levels of selected ARGs than the raw agricultural soils (p < 0.05). Average relative abundances of (intI1, sul1, blaSHV, and ermB) genes were significantly higher in biosolid-amended soils compared to nearby agricultural soils (p < 0.05). A spatial interpolation analysis of relative gene abundances (of intI1, sul1, sul2, and tetW) across the studied area indicated directional trends towards the northwest and southeast directions, highlighting possible airborne spread. Hung et al. concluded that this study brings attention to the need to redefine our antimicrobial standards in soils in terms of public health, in addition to highlighting the importance of considering relatively unstudied transmission routes, such as groundwater and air, when dealing with the current worldwide antibiotic resistance crisis [15]. Aging, degradation, and synergistic effects of emerging pollutants The actual fate of organic pollutants in soil is governed by many different factors including soil characteris- tics, compound properties, and environmental factors such as temperature, precipitation, and the ability of soil microbes to degrade the compound [32, 117]. Emerging Fig. 2 Biosolids from WWTPs used as agricultural soil fertilizer contain bacteria (green rectangles) with resistance plasmids (orange circles). These biosol- ids can spread the resistance plasmids further, and through direct or indirect routes transfer to human pathogen and commensal bacteria (red rectangles with black spikes) [18] Page 7 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 pollutants have now also been spread into areas where biosolids have not been land applied because of their per- sistence during long distance transport and bioaccumu- lation. For example, land applied biosolids enriched with longer chain PFAS can be adsorbed to microplastics or dust and become airborne [3]. Biosolids can also release fine particles or colloids when subjected to natural drying and freeze thaw cycles, which can carry PFAS to subsur- face and ground water [3, 118, 119]. The fate of emerging pollutants in biosolids after land application can vary based on physicochemical proper- ties of the organic compound, the treatment process used to generate the biosolids, and soil properties (e.g., pH and organic carbon), as well as climate [120–125]. Organic compounds present in biosolids, however, can be mobi- lized during rainfall events following land application, and have been detected in both the dissolved phase, as well as associated with suspended particulates [126, 127]. Gottschall et al. reported the presence of PPCPs in agri- cultural tile drainage and ground water after application of dewatered biosolids [128]. While Gottschall et al., indicate that the dissipation of many PPCPs in biosolids- amended soils occurs within the first few months after application, some PPCPs, including those in biosolid aggregates incorporated into soil, can still be detected for more than one year following biosolids land application. Emerging pollutants can also be transformed during degradation into products that have similar biological activity or can have greater toxicity than the parent com- pound [129, 130]. Macherius et al. reported the forma- tion of triclosan conjugates in carrot cell cultures such that the quantity of conjugates exceeded the amount of parent triclosan by a factor of five [131]. Mordechay et al., reported extensive epoxidation of carbamazepine in the leaves of multiple plant species exposed to the pharmaceutical [132]. More information is needed on the importance of the production of contaminant trans- formation products after environmental release of these compounds, and the potential for further transloca- tion of pollutants and transformation products beyond plants, especially among nontarget organisms consum- ing exposed plants [133]. In addition, further study of the role of environmental factors such as rhizosphere microorganisms may play in uptake and transformation of pharmaceuticals in the environment is required [133]. Another factor widely recognized as affecting the bio- availability of organic contaminants in soil is residence time. As soil pollutant contact time increases, pollutant bioavailability and extractability decrease [32, 117]. Dur- ing aging, pollutants slowly diffuse into the soil matrix via isomorphic dissolution reactions, thus becoming increas- ingly inaccessible for biodegradation and bioaccumula- tion [32]. Weathering and aging have been reported to result in decreased toxicity and bioavailability of many soil-applied chemicals [32, 134]. And since long-term aging reactions modify organic contaminants’ availabil- ity and toxicity over time, they are important in human and ecological risk assessments and the development of soil quality standards [32]. For instance, sediments can become potentially bioavailable to benthic organisms, and if the level of bioaccumulation is high, they can gen- erate acute and chronic exposure and spread to higher trophic levels [29, 135–137]. Recalcitrant organic con- taminants have been found to uptake into plant roots and vegetable crop plants [138–141] and earthworms that can in turn be consumed by other predators in the food chain [142, 143]. Vasilachi et al. further indicated that if emerging pol- lutants are in mixtures, the toxic effects can be cumula- tive and generate synergistic or antagonistic interactions, leading to the so-called “cocktail effect”, so that the diffi- culty of risk analysis increases [29, 144–146]. Microplas- tics, for instance, are characterized as being hydrophobic, which makes them inclined to attach to the solid matrix [20, 147]. Studies have also confirmed a high concen- tration of both and PFAS in dust samples [52, 70]. As a result of these characteristics, the application of biosol- ids as a fertilizer on agricultural fields may release pol- lutants such as microplastics and PFAS into the air and pose an inhalation risk because they are more susceptible to suspension by wind than natural soil particles [3]. In this context, the authors indicate that the precaution- ary principle needs to be applied consistently to ensure a clean and healthy environment for future generations, which is also why further studies on the risks induced by emerging pollutants, due to their specific environmental behavior, toxicity, and impacts on the environment and human health become essential [29]. Figure 3 illustrates the relationships between potential exposure pathways and potential ecological receptors after a source, such as biosolids, releases a stressor to soil. Evolution of diagnostic techniques Although some emerging pollutants and their transfor- mation by-products have existed in the environment for years, their qualitative and quantitative occurrence have been analyzed only recently [27, 29, 101, 149]. New ana- lytical techniques have made it possible to detect and quantify approximately 3000 biologically active chemi- cal compounds in the environment [29, 150–153]. How- ever, efficient and rapid methods for detection in biosolid matrices are lacking. Detection methods used to count microplastics in bio- solids may underestimate or even exclude many micro- plastics smaller than 10 μm - the fraction that could pose a greater risk for human and animal health [3, 5, 154– 156]. Thus, it is critical to develop a simple, rapid method Page 8 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 of isolating and quantifying microplastics from environ- mental samples. Hutchinson et al. demonstrated through improvements to the analytical method that levels of PFAS in biosolids are significantly higher than historically understood, indi- cating that the land application of biosolids could result in sensitive environments being exposed to PFAS at levels much higher than previously anticipated [16]. The total oxidizable precursor (TOP) assay, originally published by Houtz and Sedlak [157], has been widely used as an esti- mate of the total PFAA content of a sample, particularly in wastewater and biosolid matrices; however, it appears this method is failing to adequately digest all the PFAA precursors present in the sample [16]. Still, progress is being made in this arena. The US EPA and the Depart- ment of Defense are working to complete a multi-labo- ratory validation study of a new Method 1633 to test for 40 unique PFAS compounds in wastewater, surface water, ground water, soil, biosolids, sediment, landfill leachate, and fish tissue [158]. Future work is also needed to investigate additional compounds and transformation products that have estro- genic characteristics using non-targeted chemical analy- sis in conjunction with effects-directed analysis to gain a more comprehensive understanding of endocrine active consumer product chemicals that persist beyond their intended use in consumerism and enter the environment upon ultimate disposal [12]. Biosolids treatment to remove emerging pollutants Research and experiments into new technologies, or a combination of technologies are needed to reduce the risk wastewater and biosolids can have on the environment and human health as conventional waste- water treatment plants are, in principle, not designed to remove emerging pollutants [22, 31]. In April of 2020, the United States Environmental Protection Agency (US EPA) formed the PFAS Innovative Treatment Team to explore innovative tools and methods for destroying all the carbon fluorine (C-F) bonds in PFAS-containing waste [159]. The work resulted in improved understand- ing and advancement of four innovative non-combustion technologies to supplement ongoing EPA research into PFAS treatment. These technologies are electrochemical oxidation (EO), supercritical water oxidation (SCWO), mechanochemical degradation, and gasification and pyrolysis [160]. Berg et al. describes EO as being used to oxidize pol- lutants by means of passing an electrical current through a solution [159]. They describe that the electronegativity and electron affinity of fluorine allows the C-F bond to be broken and the fluorine atoms reduced when a high over- potential is applied to a solution. Their review of SCWO indicates that preliminary studies on biosolids treatment have shown strong reductions in PFOS and PFOA levels in the processed effluent. They also indicate that suffi- ciently dewatered sludge, or wet sludge dried by addition of co-milling agents, would be applicable to treatment in a mechanochemical degradation system. However, they indicate no such tests with PFAS have been identified in the literature. They further indicate that PFAS test- ing on a biosolids pyrolysis system was repeated in a test commissioned by the PFAS Innovative Treatment Team confirming high levels of degradation of the target PFAS compounds analyzed in the feed. Research to evaluate Fig. 3 The diagram illustrates relationships between potential exposure pathways and potential ecological receptors after a source releases a stressor to soil [148] Page 9 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 these promising technologies for PFAS destruction are ongoing. Chen et al. indicates that hydrothermal processing (HTP), including hydrothermal carbonization (HTC) and hydrothermal liquefaction (HTL), is a promising method to sustainably manage biosolids because it can convert it into useful products while mitigating the environmental risks of biosolids simultaneously [161]. They describe that products from HTP are normally biocrude oil, aqueous products (containing fertilizer precursors), and hydrochar. The authors also indicate that HTC has been extensively used for phosphorus recovery, while HTL can effectively remove constituents of emerging concern. They go on to indicate that energy analysis of HTP indi- cates that HTP has a 11-fold higher energy recovery than landfilling [162]. Low temperature mineralization of perfluorocarbox- ylic acids is also being experimented with. Trang et al. found that perfluoroalkyl carboxylic acids (PFCAs) could be mineralized through a sodium hydroxide-mediated defluorination pathway [163]. Their study found that PFCA decarboxylation in polar aprotic solvents produced reactive perfluoroalkyl ion intermediates that degraded to fluoride ions (78 to ~ 100%) within 24 h. The study also indicates that degradation was observed for branched perfluoroalkyl ether carboxylic acids. They surmised that this may then inform the development of engineered PFAS degradation processes and facilitate expanding this reactivity mode to PFAS with other polar head groups. For perspective, and as described by Vasilachi et al., source reduction and substitution of emerging pollutants with products having lower toxicity and easier removal from water have played an important role in reducing the impact of emerging pollutants on the environment and human health [29]. Amending biosolids with biochar or wood chips has been demonstrated to significantly enhance the degradation and/or retention (sorption) of target total and(or) leachable pharmaceuticals [164]. However, one should keep in mind that the solution to pollution should not always be dilution, so efforts to treat biosolids to remove contaminants of potential risk to health and the environment should continue to be pursued, particularly due to the demonstrated bioper- sistence of many of these synthetic organic chemicals. Related to PFAS, another study of commercial biosol- ids from the U.S. and Canada found that while thermal hydrolysis had no apparent effect on the PFAA concen- tration, heat treatment and composting increased PFAA concentrations (especially PFHxA) via the degradation of precursors [165]. Only blending with PFAS-free material decreased the concentration of PFAAs in the commercial biosolids, by diluting it. With millions of tons of biosol- ids being land applied annually, dilution cannot be a sus- tainable or a long-term treatment solution to removing contaminants that persist and bioaccumulate in the environment. The California Department of Toxic Substances Control chemical profile for PFAS, “Product – Chemical Profile for Treatments Containing Perfluoroalkyl or Polyfluoroal- kyl Substances for Use on Converted Textiles or Leathers” (February 2021 Final Version) indicates that intentional or accidental combustion of PFAS forms hazardous chemicals [84]. For instance, the combustion of various fluorinated polymers can result in emissions of C3-C14 PFCAs, ozone-depleting substances such as chlorofluo- rocarbons, and greenhouse gases such as fluorocarbons when fluoropolymers are combusted at temperatures representative of municipal incinerators [166]. During incineration at temperatures above 450 °C, Polytetrafluo- roethylene (PTFE) (aka Teflon) also forms additional haz- ardous substances including the ultra-short-chain PFAA tetrafluoroacetic acid and hydrofluoric acid (HF) [166, 167]. Moreover, an industry-sponsored study in a rotary kiln test facility simulating municipal incinerators found that PTFE polymer pellets begin to decompose at around 500˚C, and by approximately 650˚C they completely con- vert to HF gas and F-containing ash, with no significant PFAA emissions [168]. Other authors have reported that at lower temperatures, as could occur during acciden- tal landfill fires, fluoropolymers such as PTFE can break down into PFCAs, including PFOA [169, 170]. In this regard, future technologies need to be both effective and environmentally-friendly treatments, capa- ble of removing the widest possible spectrum of emerg- ing pollutants, with low energy consumption and capital expenditures. And the efficiency of the treatment must be adjustable to emerging pollutants concentrations in an aquatic environment to make it possible to recover the treated water [29]. Monitoring and regulations The lack of standards and regulations for the emerging pollutants discussed in this review are due, in part, to lack of available data on the effects of chronic exposure on human health. This underscores the need for complete epidemiological and toxicological studies, in addition to the development of better treatment technologies, and standardized diagnostic testing methods for monitoring emerging pollutants in biosolids. Additionally, systematic approaches are needed to identify and prioritize pollut- ants of emerging concern [10, 171]. A complete ban on land application would not only place a heavy burden on public municipalities but could also lead to unintended consequences [172]. Recently, two states in the US have adopted regula- tions relating to the presence of PFAS substances in biosolids. In 2021 under an interim strategy, Michigan began prohibiting the land application of industrially Page 10 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 impacted biosolids containing more than 150 parts per billion (ppb) of PFOS and requires testing of biosolids prior to land application. On April 15, 2022, the Maine state House and Senate both passed a bill (LD 1911) that would ban the use of biosolids that contain PFAS in land applications, unless it can be shown that the biosolids are PFAS free. On the national level, in a move toward regulation of PFAS, EPA Administrator Michael S. Regan announced the Agency’s PFAS Strategic Roadmap on October 18, 2021. The roadmap charts an approach to addressing PFAS with EPA’s Commitments to Action steps that take place between 2021 and 2024. In addition, the EPA’s Office of Water developed a Biosolids Chemical Risk Assessment and Biosolids Screening Tool (BST) with an accompanying User Guide to identify pollutants, path- ways, and receptors of greatest interest and to inform decisions regarding the need for refined risk assessment of land-applied biosolids. In late 2021, the US EPA also selected a Science Advisory Board to review and pro- vide input on the overall risk assessment approach and on the scientific credibility and usability of the BST. But these actions have not yet translated into protective stan- dards for public health with respect to biosolids land application. Discussion From a regulatory standpoint, there is an urgent and crit- ical need to modernize environmental health standards that pertain to the land application of biosolids. Current US EPA regulatory standards have not been updated since 1993 and do not take the emerging contaminants described in this review into account. The revision of these standards should be risk-based, prioritizing emerg- ing pollutants that are persistent and can bioaccumu- late. Support should be provided for the development of novel technologies to better treat biosolids to remove the contaminants of concern before they are land applied and novel methods for recycling or reuse of these pollut- ants should be explored. However, these changes require political will and collaboration among state and federal agencies to prioritize new policies and regulations. Ongoing development of analytical methodologies for identifying emerging contaminants in soil, water, waste, and other media should be a priority of relevant regula- tory agencies. Of note, Hutchinson et al. indicate that a standardized analytical methodology is needed to protect environmental assets from PFAS contamination from land-applied biosolids [16]. Inconsistencies between cur- rent testing methods used to detect and measure emerg- ing pollutants, likely underestimate concentrations of these pollutants in receiving matrices, especially where published quantification methods are adapted to bio- solids but not the receiving matrix. At the time of this writing, the US EPA is developing a new standardized testing methodology; however, the authors’ conclusions remain relevant as prior studies have not captured a com- plete picture of the extent and impact of contamination. More research is also needed to assess the long-term human health risks from exposure to emerging pollut- ants. The ecological risks of microplastics in agricultural soils urgently need to be assessed with respect to animals, plants, and microorganisms inhabiting soils and humans involved via the food web. Additionally, future studies should measure microplastics and associated PFAS in dust from biosolids and quantify exposure risks via inha- lation. Studies evaluating the factors that contribute to the fate of emerging pollutants must be conducted to bet- ter understand exposure routes and the risks of surface and ground water contamination with these pollutants. Lastly, effective communication to the public on the significance of pharmaceutical ingestion and personal care product use and the resulting environmental effects due to runoff from agricultural land may help to put pressure on decision-makers and create an awareness of unwarranted excessive use of these products [32]. This also presents an opportunity to promote use of more sus- tainable products to reduce the volume of contaminants that are released to the environment via wastewater infrastructure pathways. Conclusion Humans are being continuously exposed to the emerg- ing pollutants described in this review and a concerted effort should be made to mitigate these exposures and risks among the general public, policymakers, wastewa- ter treatment plant operators, and farmers, in terms of raising awareness, controlling the sources, and establish- ing a reasonable regulatory risk level for biosolids reuse. As a society we must also promote the use of more envi- ronmentally sustainable products that can be flushed into the environment. Research indicates that biosolids contain a complex mixture of contaminants, and investment in effective treatment and diagnostic technologies are essential for detecting and reducing the presence of contaminants so the benefits of biosolids related to carbon sequestra- tion and soil health can be fully realized. We should reconsider the continued land application of biosolids in this seemingly endless loop of spreading contaminants into our environment, and we should most certainly not continue to do it in the name of recycling, climate change, and soil health. Instead, efforts need to be pur- sued to work within the current system to better com- municate and act upon the human health risks in order to achieve desired public health outcomes. Significant funding and support for upgrading wastewater treatment Page 11 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 infrastructure are also needed to address these issues of today in order to better prepare for a safer tomorrow. A final note to ponder as we consider this issue. Biosol- ids, in their current form, have often been referred to as an organic waste to be recovered and recycled. But given the presence of contaminants that originate from both domestic and industrial wastewater sources, is that really the appropriate designation in law or regulation? As a society, if we fail to take definite policy actions to mod- ernize environmental standards that pertain to the land application of biosolids, and continue to land apply layer upon layer of these complex mixtures of pollutants to our soil without adequate public health protections in place, and without regard to the long-term environmental con- sequences, we may potentially cause irreversible damage to the very soils we use to grow our food and to our sur- face and ground water that sustain life. Supplementary Information The online version contains supplementary material available at https://doi. org/10.1186/s12940-023-01008-4. Supplemental Fig. 1. PRISMA Flow Diagram Acknowledgements This literature review was prepared with the support of the California Conference of Directors of Environmental Health (CCDEH) Executive Committee and Executive Director Justin Malan; the CCDEH Water and Land Policy Committee Chaired by Vicki Jones, REHS; and the CCDEH Solid Waste Resource and Recovery Committee co-chaired by Lars Seifert, REHS and Charles Genkel, REHS. CCDEH would also like to thank Chad A. Kinney, Ph.D. who assisted with peer review. Authors’ contributions E.P. provided conceptualization of the literature review; E.P. collected and reviewed the scientific literature and wrote the manuscript text; and L.S. contributed editorially to the structure of the manuscript and supported the implementation of the literature review. All authors reviewed the manuscript. Funding Not applicable. No funding was received to assist with the preparation of this manuscript. Data Availability Not applicable. All literature cited is available at the reference provided. Declarations Competing interests The authors have no conflicts of interest to declare that are relevant to the content of this article. All authors certify that they have no affiliations with or involvement in any organization or entity with any financial or non-financial interest in the subject matter or materials discussed in this manuscript. E.P. is a recently retired County of San Luis Obispo Environmental Health Director, and L.S. is employed as the Environmental Health Services Director for Santa Barbara County, California. Authors are both participating members in the California Conference of Directors of Environmental Health, a 501(3)c non- profit professional association. Ethics approval and consent to participate Not applicable. Consent for publication Not applicable. Received: 17 October 2022 / Accepted: 14 August 2023 References 1. Broderick SR, Evans WB. Biosolids promote similar plant growth and quality responses as conventional and slow-release fertilizers. HortTechnology hortte. 2017;27(6):794–804. 2. Shober AL, Stehouwer RC, Macneal KE. On-Farm Assessment of Biosolids Effects on Soil and Crop tissue quality. J Environ Qual. 2003;32(5):1873–80. 3. Borthakur A, Leonard J, Koutnik VS, Ravi S, Mohanty SK. Inhalation risks of wind-blown dust from biosolid-applied agricultural lands: are they enriched with microplastics and PFAS? Curr Opin Environ Sci Health. 2022;25:100309. 4. Crossman J, Hurley RR, Futter M, Nizzetto L. Transfer and transport of micro- plastics from biosolids to agricultural soils and the wider environment. Sci Total Environ. 2020;724:138334. 5. Koutnik VS, Alkidim S, Leonard J, DePrima F, Cao S, Hoek EMV, Mohanty SK. Unaccounted microplastics in Wastewater Sludge: where do they go? ACS ES&T Water. 2021;1(5):1086–97. 6. Mohajerani A, Karabatak B. Microplastics and pollutants in biosolids have contaminated agricultural soils: an analytical study and a proposal to cease the use of biosolids in farmlands and utilise them in sustainable bricks. Waste Manag. 2020;107:252–65. 7. Benítez E, Romero E, Gómez M, Gallardo-Lara F, Nogales R. Biosolids and Biosolids-ash as sources of Heavy Metals in a plant-soil system. Water Air Soil Pollut. 2001;132(1):75–87. 8. Munir M, Xagoraraki I. Levels of Antibiotic Resistance genes in Manure, Biosol- ids, and fertilized soil. J Environ Qual. 2011;40(1):248–55. 9. Harrison EZ, Oakes SR, Hysell M, Hay A. Organic chemicals in sewage sludges. Sci Total Environ. 2006;367(2):481–97. 10. Venkatesan AK, Halden RU. National inventory of perfluoroalkyl substances in archived U.S. biosolids from the 2001 EPA National Sewage Sludge Survey. J Hazard Mater. 2013;252–253:413–8. 11. Paz-Ferreiro J, Nieto A, Méndez A, Askeland MP, Gascó G. Biochar from Biosol- ids Pyrolysis: a review. In: Int J Environ Res Public Health vol. 15; 2018. 12. Black GP, Anumol T, Young Thomas M. Analyzing a broader spectrum of endocrine active organic contaminants in sewage sludge with high resolu- tion LC-QTOF-MS suspect screening and QSAR toxicity prediction. Environ Science: Processes Impacts. 2019;21(7):1099–114. 13. Corradini F, Meza P, Eguiluz R, Casado F, Huerta-Lwanga E, Geissen V. Evidence of microplastic accumulation in agricultural soils from sewage sludge dis- posal. Sci Total Environ. 2019;671:411–20. 14. Helmer RW, Reeves DM, Cassidy DP. Per- and Polyfluorinated Alkyl Substances (PFAS) cycling within Michigan: contaminated sites, landfills and wastewater treatment plants. Water Res. 2022;210:117983. 15. Hung W-C, Miao Y, Truong N, Jones A, Mahendra S, Jay J. Tracking antibiotic resistance through the environment near a biosolid spreading ground: resistome changes, distribution, and metal(loid) co-selection. Sci Total Envi- ron. 2022;823:153570. 16. Hutchinson S, Rieck T, Wu X. Advanced PFAS precursor digestion methods for biosolids. Environ Chem. 2020;17(8):558–67. 17. Johnson GR. PFAS in soil and groundwater following historical land applica- tion of biosolids. Water Res. 2022;211:118035. 18. Law A, Solano O, Brown CJ, Hunter SS, Fagnan M, Top EM, Stalder T. Biosolids as a source of antibiotic resistance plasmids for commensal and pathogenic Bacteria. Front Microbiol 2021, 12. 19. Sepulvado JG, Blaine AC, Hundal LS, Higgins CP. Occurrence and fate of Per- fluorochemicals in Soil following the Land Application of Municipal Biosolids. Environ Sci Technol. 2011;45(19):8106–12. 20. Liu H, Wang Z, Nghiem LD, Gao L, Zamyadi A, Zhang Z, Sun J, Wang Q. Solid- embedded microplastics from Sewage Sludge to Agricultural Soils: detection, occurrence, and impacts. ACS ES&T Water. 2021;1(6):1322–33. 21. Sherburne JJ, Anaya AM, Fernie KJ, Forbey JS, Furlong ET, Kolpin DW, Dufty AM, Kinney CA. Occurrence of Triclocarban and Triclosan in an agro-ecosystem following application of Biosolids. Environ Sci Technol. 2016;50(24):13206–14. Page 12 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 22. Koumaki E, Noutsopoulos C, Mamais D, Fragkiskatos G, Andreadakis A. Fate of emerging contaminants in high-rate activated Sludge Systems. In: Int J Environ Res Public Health vol. 18; 2021. 23. Black GP, He G, Denison MS, Young TM. Using estrogenic activity and Nontar- geted Chemical Analysis to identify contaminants in Sewage Sludge. Environ Sci Technol. 2021;55(10):6729–39. 24. Steele JC, Meng X-Z, Venkatesan AK, Halden RU. Comparative meta-analysis of organic contaminants in sewage sludge from the United States and China. Sci Total Environ. 2022;821:153423. 25. [https://www.epa.gov/biosolids/basic-information-about-biosolids]. 26. Biosolids. Global Strategic Business Report [https:// www.researchandmarkets.com/reports/5139451/ biosolids-global-strategic-business-report#rela0-5327510]. 27. Gavrilescu M, Demnerová K, Aamand J, Agathos S, Fava F. Emerging pollut- ants in the environment: present and future challenges in biomonitoring, ecological risks and bioremediation. New Biotechnol. 2015;32(1):147–56. 28. Petrie B, Barden R, Kasprzyk-Hordern B. A review on emerging contaminants in wastewaters and the environment: current knowledge, understudied areas and recommendations for future monitoring. Water Res. 2015;72:3–27. 29. Vasilachi IC, Asiminicesei DM, Fertu DI, Gavrilescu M. Occurrence and fate of emerging pollutants in Water Environment and Options for their removal. In: Water vol. 13; 2021. 30. United Nations Environment Programme. : An Assessment Report on Issues of Concern: Chemicals and Waste Issues Posing Risks to Human Health and the Environment. In.; 2020. 31. Richardson SD, Ternes TA. Water Analysis: emerging contaminants and cur- rent issues. Anal Chem. 2018;90(1):398–428. 32. Clarke RM, Cummins E. Evaluation of “Classic” and emerging contaminants resulting from the application of Biosolids to Agricultural Lands: a review. Hum Ecol Risk Assessment: Int J. 2015;21(2):492–513. 33. Lenka SP, Kah M, Padhye LP. A review of the occurrence, transformation, and removal of poly- and perfluoroalkyl substances (PFAS) in wastewater treat- ment plants. Water Res. 2021;199:117187. 34. Lindstrom AB, Strynar MJ, Delinsky AD, Nakayama SF, McMillan L, Libelo EL, Neill M, Thomas L. Application of WWTP Biosolids and resulting perfluo- rinated compound contamination of Surface and Well Water in Decatur, Alabama, USA. Environ Sci Technol. 2011;45(19):8015–21. 35. Lee H, Tevlin AG, Mabury SA, Mabury SA. Fate of polyfluoroalkyl phosphate diesters and their metabolites in Biosolids-Applied Soil: Biodegradation and Plant Uptake in Greenhouse and Field experiments. Environ Sci Technol. 2014;48(1):340–9. 36. Schowanek D, Carr R, David H, Douben P, Hall J, Kirchmann H, Patria L, Sequi P, Smith S, Webb S. A risk-based methodology for deriving quality standards for organic contaminants in sewage sludge for use in agriculture—conceptual Framework. Regul Toxicol Pharmacol. 2004;40(3):227–51. 37. Prosser RS, Sibley PK. Human health risk assessment of pharmaceuticals and personal care products in plant tissue due to biosolids and manure amend- ments, and wastewater irrigation. Environ Int. 2015;75:223–33. 38. What are Microplastics?. [https://oceanservice.noaa.gov/facts/microplastics. html]. 39. Murphy F, Ewins C, Carbonnier F, Quinn B. Wastewater Treatment Works (WwTW) as a source of Microplastics in the aquatic environment. Environ Sci Technol. 2016;50(11):5800–8. 40. Liu X, Yuan W, Di M, Li Z, Wang J. Transfer and fate of microplastics during the conventional activated sludge process in one wastewater treatment plant of China. Chem Eng J. 2019;362:176–82. 41. Hidayaturrahman H, Lee T-G. A study on characteristics of microplastic in wastewater of South Korea: identification, quantification, and fate of micro- plastics during treatment process. Mar Pollut Bull. 2019;146:696–702. 42. Allen S, Allen D, Phoenix VR, Le Roux G, Durántez Jiménez P, Simonneau A, Binet S, Galop D. Atmospheric transport and deposition of microplastics in a remote mountain catchment. Nat Geosci. 2019;12(5):339–44. 43. Brahney J, Hallerud M, Heim E, Hahnenberger M, Sukumaran S. Plastic rain in protected areas of the United States. Science. 2020;368(6496):1257–60. 44. Evangeliou N, Grythe H, Klimont Z, Heyes C, Eckhardt S, Lopez-Aparicio S, Stohl A. Atmospheric transport is a major pathway of microplastics to remote regions. Nat Commun. 2020;11(1):3381. 45. Feng S, Lu H, Tian P, Xue Y, Lu J, Tang M, Feng W. Analysis of microplastics in a remote region of the Tibetan Plateau: implications for natural environmental response to human activities. Sci Total Environ. 2020;739:140087. 46. Peeken I, Primpke S, Beyer B, Gütermann J, Katlein C, Krumpen T, Bergmann M, Hehemann L, Gerdts G. Arctic sea ice is an important temporal sink and means of transport for microplastic. Nat Commun. 2018;9(1):1505. 47. Prata JC, da Costa JP, Lopes I, Duarte AC, Rocha-Santos T. Environmental exposure to microplastics: an overview on possible human health effects. Sci Total Environ. 2020;702:134455. 48. Prata JC. Airborne microplastics: consequences to human health? Environ Pollut. 2018;234:115–26. 49. Dehghani S, Moore F, Akhbarizadeh R. Microplastic pollution in deposited urban dust, Tehran metropolis, Iran. Environ Sci Pollut Res. 2017;24(25):20360–71. 50. Gasperi J, Wright SL, Dris R, Collard F, Mandin C, Guerrouache M, Langlois V, Kelly FJ, Tassin B. Microplastics in air: are we breathing it in? Curr Opin Environ Sci Health. 2018;1:1–5. 51. Mbachu O, Jenkins G, Pratt C, Kaparaju P. A New Contaminant Superhighway? A review of sources, measurement techniques and Fate of Atmospheric Microplastics. Water Air Soil Pollut. 2020;231(2):85. 52. Pramanik BK, Roychand R, Monira S, Bhuiyan M, Jegatheesan V. Fate of road- dust associated microplastics and per- and polyfluorinated substances in stormwater. Process Saf Environ Prot. 2020;144:236–41. 53. Abbasi S, Keshavarzi B, Moore F, Turner A, Kelly FJ, Dominguez AO, Jaafar- zadeh N. Distribution and potential health impacts of microplastics and microrubbers in air and street dusts from Asaluyeh County, Iran. Environ Pollut. 2019;244:153–64. 54. Järlskog I, Strömvall A-M, Magnusson K, Gustafsson M, Polukarova M, Galfi H, Aronsson M, Andersson-Sköld Y. Occurrence of tire and bitumen wear micro- plastics on urban streets and in sweepsand and washwater. Sci Total Environ. 2020;729:138950. 55. Liu K, Wang X, Song Z, Wei N, Li D. Terrestrial plants as a potential tempo- rary sink of atmospheric microplastics during transport. Sci Total Environ. 2020;742:140523. 56. Rillig MC. Microplastic in Terrestrial Ecosystems and the Soil? Environ Sci Technol. 2012;46(12):6453–4. 57. Calderón-Preciado D, Matamoros V, Bayona JM. Occurrence and potential crop uptake of emerging contaminants and related compounds in an agri- cultural irrigation network. Sci Total Environ. 2011;412–413:14–9. 58. Krause S, Molari M, Gorb EV, Gorb SN, Kossel E, Haeckel M. Persistence of plas- tic debris and its colonization by bacterial communities after two decades on the abyssal seafloor. Sci Rep. 2020;10(1):9484. 59. Buck RC, Franklin J, Berger U, Conder JM, Cousins IT, de Voogt P, Jensen AA, Kannan K, Mabury SA, van Leeuwen SPJ. Perfluoroalkyl and polyfluoroalkyl substances in the environment: terminology, classification, and origins. Integr Environ Assess Manag. 2011;7(4):513–41. 60. Dean WS, Adejumo HA, Caiati A, Garay PM, Harmata AS, Li L, Rodriguez EE, Sundar S. A Framework for Regulation of New and existing PFAS by EPA. J Sci Policy Gov. 2020;16(1):1–14. 61. Chow SJ, Ojeda N, Jacangelo JG, Schwab KJ. Detection of ultrashort-chain and other per- and polyfluoroalkyl substances (PFAS) in U.S. bottled water. Water Res. 2021;201:117292. 62. Cousins IT, Vestergren R, Wang Z, Scheringer M, McLachlan MS. The precau- tionary principle and chemicals management: the example of perfluoroalkyl acids in groundwater. Environ Int. 2016;94:331–40. 63. Kotlarz N, McCord J, Collier D, Lea CS, Strynar M, Lindstrom AB, Wilkie AA, Islam JY, Matney K, Tarte P, et al. Measurement of Novel, drinking Water-Asso- ciated PFAS in blood from adults and children in Wilmington, North Carolina. Environ Health Perspect. 2020;128(7):077005. 64. Scheringer M, Trier X, Cousins IT, de Voogt P, Fletcher T, Wang Z, Webster TF. Helsingør Statement on poly- and perfluorinated alkyl substances (PFASs). Chemosphere. 2014;114:337–9. 65. Glüge J, Scheringer M, Cousins IT, DeWitt JC, Goldenman G, Herzke D, Lohmann R, Ng CA, Trier X, Wang Z. An overview of the uses of per- and polyfluoroalkyl substances (PFAS). Environ Science: Processes Impacts. 2020;22(12):2345–73. 66. Armstrong DL, Lozano N, Rice CP, Ramirez M, Torrents A. Temporal trends of perfluoroalkyl substances in limed biosolids from a large municipal water resource recovery facility. J Environ Manage. 2016;165:88–95. 67. Miner KR, Clifford H, Taruscio T, Potocki M, Solomon G, Ritari M, Napper IE, Gajurel AP, Mayewski PA. Deposition of PFAS ‘forever chemicals’ on Mt. Ever- est. Sci Total Environ. 2021;759:144421. 68. Prevedouros K, Cousins IT, Buck RC, Korzeniowski SH. Sources, fate and trans- port of Perfluorocarboxylates. Environ Sci Technol. 2006;40(1):32–44. Page 13 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 69. Butt CM, Berger U, Bossi R, Tomy GT. Levels and trends of poly- and perfluorinated compounds in the arctic environment. Sci Total Environ. 2010;408(15):2936–65. 70. Young AS, Sparer-Fine EH, Pickard HM, Sunderland EM, Peaslee GF, Allen JG. Per- and polyfluoroalkyl substances (PFAS) and total fluorine in fire station dust. J Expo Sci Environ Epidemiol. 2021;31(5):930–42. 71. Nicole W. Breaking it down: estimating short-chain PFAS half-lives in a Human Population. Environ Health Perspect. 2020;128(11):114002. 72. Sáez M, de Voogt P, Parsons JR. Persistence of perfluoroalkylated substances in closed bottle tests with municipal sewage sludge. Environ Sci Pollut Res. 2008;15(6):472–7. 73. Zareitalabad P, Siemens J, Hamer M, Amelung W. Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in surface waters, sediments, soils and wastewater – a review on concentrations and distribution coef- ficients. Chemosphere. 2013;91(6):725–32. 74. Shin H-M, Vieira VM, Ryan PB, Detwiler R, Sanders B, Steenland K, Bartell SM. Environmental fate and transport modeling for Perfluorooctanoic Acid emit- ted from the Washington Works Facility in West Virginia. Environ Sci Technol. 2011;45(4):1435–42. 75. De Silva AO, Armitage JM, Bruton TA, Dassuncao C, Heiger-Bernays W, Hu XC, Kärrman A, Kelly B, Ng C, Robuck A, et al. PFAS exposure pathways for humans and Wildlife: a synthesis of current knowledge and key gaps in understanding. Environ Toxicol Chem. 2021;40(3):631–57. 76. Kennedy GL, Butenhoff JL, Olsen GW, O’Connor JC, Seacat AM, Perkins RG, Biegel LB, Murphy SR, Farrar DG. The Toxicology of Perfluorooctanoate. Crit Rev Toxicol. 2004;34(4):351–84. 77. Sunderland EM, Hu XC, Dassuncao C, Tokranov AK, Wagner CC, Allen JG. A review of the pathways of human exposure to poly- and perfluoroalkyl substances (PFASs) and present understanding of health effects. J Expo Sci Environ Epidemiol. 2019;29(2):131–47. 78. Trudel D, Horowitz L, Wormuth M, Scheringer M, Cousins IT, Hunger- bühler K. Estimating consumer exposure to PFOS and PFOA. Risk Anal. 2008;28(2):251–69. 79. Conder JM, Hoke RA, Wolf Wd, Russell MH, Buck RC. Are PFCAs Bioaccumula- tive? A critical review and comparison with Regulatory Criteria and Persistent Lipophilic Compounds. Environ Sci Technol. 2008;42(4):995–1003. 80. Martin JW, Whittle DM, Muir DCG, Mabury SA. Perfluoroalkyl Contaminants in a Food web from Lake Ontario. Environ Sci Technol. 2004;38(20):5379–85. 81. Pérez F, Nadal M, Navarro-Ortega A, Fàbrega F, Domingo JL, Barceló D, Farré M. Accumulation of perfluoroalkyl substances in human tissues. Environ Int. 2013;59:354–62. 82. Agency for Toxic Substances and Disease Registry (US). Toxicological Profile for Perfluoroalkyls. Atlanta, GA: Agency for Toxic Substances and Disease Registry (US); 2021. 83. Sørli JB, Låg M, Ekeren L, Perez-Gil J, Haug LS, Da Silva E, Matrod MN, Gützkow KB, Lindeman B. Per- and polyfluoroalkyl substances (PFASs) modify lung surfactant function and pro-inflammatory responses in human bronchial epithelial cells. Toxicol In Vitro. 2020;62:104656. 84. Product. – Chemical Profile for Treatments Containing Perfluoroalkyl or Poly- fluoroalkyl Substances for Use on Converted Textiles or Leathers. In. Edited by Control DoTS; 2021. 85. Calafat AM, Kuklenyik Z, Reidy JA, Caudill SP, Tully JS, Needham LL. Serum concentrations of 11 Polyfluoroalkyl Compounds in the U.S. Population: data from the National Health and Nutrition Examination Survey (NHANES) 1999 – 2000. Environ Sci Technol. 2007;41(7):2237–42. 86. Toxicological Effects of Perfluoroalkyl and Polyfluoroalkyl Substances., 1 edn: Humana Cham; 2015. 87. Borthakur A, Wang M, He M, Ascencio K, Blotevogel J, Adamson DT, Mahen- dra S, Mohanty SK. Perfluoroalkyl acids on suspended particles: significant transport pathways in surface runoff, surface waters, and subsurface soils. J Hazard Mater. 2021;417:126159. 88. Wang Y, Huang H. Chap. 8 - Carbon nanotube composite membranes for microfiltration of pharmaceuticals and personal care products. In: Advanced Nanomaterials for Membrane Synthesis and its Applications Edited by Lau W-J, Ismail AF, Isloor A, Al-Ahmed A: Elsevier; 2019: 183–202. 89. Bishnoi MM, Verma A, Kushwaha A, Goswami S. Chap. 9 - Social factors influencing household waste management. In: Emerging Trends to Approach- ing Zero Waste Edited by Hussain CM, Singh S, Goswami L: Elsevier; 2022: 197–213. 90. Bayabil HK, Teshome FT, Li YC. Emerging contaminants in Soil and Water. Front Environ Sci 2022, 10. 91. Cooper ER, Siewicki TC, Phillips K. Preliminary risk assessment database and risk ranking of pharmaceuticals in the environment. Sci Total Environ. 2008;398(1):26–33. 92. Wang J, Wang S. Removal of pharmaceuticals and personal care products (PPCPs) from wastewater: a review. J Environ Manage. 2016;182:620–40. 93. Clarke BO, Smith SR. Review of ‘emerging’ organic contaminants in biosolids and assessment of international research priorities for the agricultural use of biosolids. Environ Int. 2011;37(1):226–47. 94. Körner W, Bolz U, Süßmuth W, Hiller G, Schuller W, Hanf V, Hagenmaier H. Input/output balance of estrogenic active compounds in a major municipal sewage plant in Germany. Chemosphere. 2000;40(9):1131–42. 95. Langdon KA, Warne MSJ, Smernik RJ, Shareef A, Kookana RS. Selected per- sonal care products and endocrine disruptors in biosolids: an Australia-wide survey. Sci Total Environ. 2011;409(6):1075–81. 96. Chen J, Pycke BFG, Brownawell BJ, Kinney CA, Furlong ET, Kolpin DW, Halden RU. Occurrence, temporal variation, and estrogenic burden of five parabens in sewage sludge collected across the United States. Sci Total Environ. 2017;593–594:368–74. 97. United States Environmental Protection Agency. : Targeted National Sewage Sludge Survey Sampling and Analysis Technical Report. In. Edited by Water Oo; 2009. 98. Guo J, Li J, Chen H, Bond PL, Yuan Z. Metagenomic analysis reveals wastewa- ter treatment plants as hotspots of antibiotic resistance genes and mobile genetic elements. Water Res. 2017;123:468–78. 99. Jelic A, Fatone F, Di Fabio S, Petrovic M, Cecchi F, Barcelo D. Tracing pharma- ceuticals in a municipal plant for integrated wastewater and organic solid waste treatment. Sci Total Environ. 2012;433:352–61. 100. Morais SA, Delerue-Matos C, Gabarrell X, Blánquez P. Multimedia fate model- ing and comparative impact on freshwater ecosystems of pharmaceuticals from biosolids-amended soils. Chemosphere. 2013;93(2):252–62. 101. Rivera-Utrilla J, Sánchez-Polo M, Ferro-García M, Prados-Joya G, Ocampo- Pérez R. Pharmaceuticals as emerging contaminants and their removal from water. A review. Chemosphere. 2013;93(7):1268–87. 102. Buta M, Hubeny J, Zieliński W, Harnisz M, Korzeniewska E. Sewage sludge in agriculture – the effects of selected chemical pollutants and emerging genetic resistance determinants on the quality of soil and crops – a review. Ecotoxicol Environ Saf. 2021;214:112070. 103. De Coster S, van Larebeke N. Endocrine-disrupting chemicals: Associated Dis- orders and Mechanisms of Action. J Environ Public Health. 2012;2012:713696. 104. Nash Jon P, Kime David E, Van der Ven Leo TM, Wester Piet W, Brion F, Maack G, Stahlschmidt-Allner P, Tyler Charles R. Long-term exposure to environmen- tal concentrations of the Pharmaceutical Ethynylestradiol causes Reproduc- tive failure in Fish. Environ Health Perspect. 2004;112(17):1725–33. 105. Kidd KA, Blanchfield PJ, Mills KH, Palace VP, Evans RE, Lazorchak JM, Flick RW. Collapse of a fish population after exposure to a synthetic estrogen. Proceed- ings of the National Academy of Sciences 2007, 104(21):8897–8901. 106. Barber LB, Vajda AM, Douville C, Norris DO, Writer JH. Fish Endocrine disrup- tion responses to a major Wastewater Treatment Facility Upgrade. Environ Sci Technol. 2012;46(4):2121–31. 107. Vajda AM, Barber LB, Gray JL, Lopez EM, Bolden AM, Schoenfuss HL, Norris DO. Demasculinization of male fish by wastewater treatment plant effluent. Aquat Toxicol. 2011;103(3):213–21. 108. OECD. : Pharmaceutical Residues in Freshwater; 2019. 109. Miraji H, Othman OC, Ngassapa FN, Mureithi EW. Research Trends in Emerg- ing Contaminants on the Aquatic Environments of Tanzania. Scientifica 2016, 2016:3769690. 110. Mortensen A, Granby K, Eriksen FD, Cederberg TL, Friis-Wandall S, Simonsen Y, Broesbøl-Jensen B, Bonnichsen R. Levels and risk assessment of chemical contaminants in byproducts for animal feed in Denmark. J Environ Sci Health Part B. 2014;49(11):797–810. 111. Cycoń M, Mrozik A, Piotrowska-Seget Z. Antibiotics in the Soil Environment— Degradation and their impact on Microbial Activity and Diversity. Front Microbiol 2019, 10. 112. Kraemer SA, Ramachandran A, Perron GG. Antibiotic Pollution in the Environ- ment: from Microbial Ecology to Public Policy. In: Microorganisms vol. 7; 2019. 113. Ross J, Topp E. Abundance of Antibiotic Resistance genes in bacterio- phage following Soil fertilization with dairy manure or municipal bio- solids, and evidence for potential transduction. Appl Environ Microbiol. 2015;81(22):7905–13. 114. Yang L, Liu W, Zhu D, Hou J, Ma T, Wu L, Zhu Y, Christie P. Application of biosolids drives the diversity of antibiotic resistance genes in soil and lettuce at harvest. Soil Biol Biochem. 2018;122:131–40. Page 14 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 115. Murray R, Tien Y-C, Scott A, Topp E. The impact of municipal sewage sludge stabilization processes on the abundance, field persistence, and transmission of antibiotic resistant bacteria and antibiotic resistance genes to vegetables at harvest. Sci Total Environ. 2019;651:1680–7. 116. Wolters B, Hauschild K, Blau K, Mulder I, Heyde BJ, Sørensen SJ, Siemens J, Jechalke S, Smalla K, Nesme J. Biosolids for safe land application: does waste- water treatment plant size matters when considering antibiotics, pollutants, microbiome, mobile genetic elements and associated resistance genes? Environ Microbiol. 2022;24(3):1573–89. 117. Reid BJ, Jones KC, Semple KT. Bioavailability of persistent organic pollutants in soils and sediments—a perspective on mechanisms, consequences and assessment. Environ Pollut. 2000;108(1):103–12. 118. Borthakur A, Cranmer BK, Dooley GP, Blotevogel J, Mahendra S, Mohanty SK. Release of soil colloids during flow interruption increases the pore-water PFAS concentration in saturated soil. Environ Pollut. 2021;286:117297. 119. Borthakur A, Olsen P, Dooley GP, Cranmer BK, Rao U, Hoek EMV, Blotevogel J, Mahendra S, Mohanty SK. Dry-wet and freeze-thaw cycles enhance PFOA leaching from subsurface soils. J Hazard Mater Lett. 2021;2:100029. 120. Tran NH, Reinhard M, Gin KY-H. Occurrence and fate of emerging contami- nants in municipal wastewater treatment plants from different geographical regions-a review. Water Res. 2018;133:182–207. 121. Chen W, Xu J, Lu S, Jiao W, Wu L, Chang AC. Fates and transport of PPCPs in soil receiving reclaimed water irrigation. Chemosphere. 2013;93(10):2621–30. 122. Al-Rajab AJ, Sabourin L, Lapen DR, Topp E. Dissipation of triclosan, triclocar- ban, carbamazepine and naproxen in agricultural soil following surface or sub-surface application of dewatered municipal biosolids. Sci Total Environ. 2015;512–513:480–8. 123. Cantarero R, Richter P, Brown S, Ascar L, Ahumada I. Effects of applying biosol- ids to soils on the adsorption and bioavailability of 17α-ethinylestradiol and triclosan in wheat plants. Environ Sci Pollut Res. 2017;24(14):12847–59. 124. Yager TJB, Furlong ET, Kolpin DW, Kinney CA, Zaugg SD, Burkhardt MR. Dis- sipation of contaminants of emerging concern in Biosolids Applied to Nonir- rigated Farmland in Eastern Colorado. JAWRA J Am Water Resour Association. 2014;50(2):343–57. 125. Wang K, Larkin T, Singhal N, Song Y. Mobility of pharmaceutical and personal care products in lime amended wastewater biosolids. Sci Total Environ. 2018;624:1263–73. 126. Yang Y-Y, Gray JL, Furlong ET, Davis JG, ReVello RC, Borch T. Steroid hormone runoff from Agricultural Test Plots Applied with Municipal Biosolids. Environ Sci Technol. 2012;46(5):2746–54. 127. Gray JL, Borch T, Furlong ET, Davis JG, Yager TJ, Yang Y-Y, Kolpin DW. Rainfall- runoff of anthropogenic waste indicators from agricultural fields applied with municipal biosolids. Sci Total Environ. 2017;580:83–9. 128. Gottschall N, Topp E, Metcalfe C, Edwards M, Payne M, Kleywegt S, Russell P, Lapen DR. Pharmaceutical and personal care products in groundwater, sub- surface drainage, soil, and wheat grain, following a high single application of municipal biosolids to a field. Chemosphere. 2012;87(2):194–203. 129. Shipkova M, Armstrong VW, Oellerich M, Wieland E. Acyl Glucuronide Drug Metabolites: Toxicological and Analytical Implications. Ther Drug Monit 2003, 25(1). 130. Walgren JL, Mitchell MD, Thompson DC. Role of metabolism in Drug-Induced Idiosyncratic Hepatotoxicity. Crit Rev Toxicol. 2005;35(4):325–61. 131. Macherius A, Eggen T, Lorenz W, Moeder M, Ondruschka J, Reemtsma T. Metabolization of the Bacteriostatic Agent Triclosan in Edible plants and its consequences for Plant Uptake Assessment. Environ Sci Technol. 2012;46(19):10797–804. 132. Ben Mordechay E, Tarchitzky J, Chen Y, Shenker M, Chefetz B. Composted biosolids and treated wastewater as sources of pharmaceuticals and personal care products for plant uptake: a case study with carbamazepine. Environ Pollut. 2018;232:164–72. 133. Kinney CA, Heuvel BV. Translocation of pharmaceuticals and personal care products after land application of biosolids. Curr Opin Environ Sci Health. 2020;14:23–30. 134. Kinney CA, Campbell BR, Thompson R, Furlong ET, Kolpin DW, Burkhardt MR, Zaugg SD, Werner SL, Hay AG. Earthworm bioassays and seedling emergence for monitoring toxicity, aging and bioaccumulation of anthropogenic waste indicator compounds in biosolids–amended soil. Sci Total Environ. 2012;433:507–15. 135. Dsikowitzky L, Crawford SE, Nordhaus I, Lindner F, Dwiyitno, Irianto HE, Ariyani F, Schwarzbauer J. Analysis and environmental risk assessment of priority and emerging organic pollutants in sediments from the tropical coastal megacity Jakarta, Indonesia. Reg Stud Mar Sci. 2020;34:101021. 136. Al Aukidy M, Verlicchi P, Jelic A, Petrovic M, Barcelò D. Monitoring release of pharmaceutical compounds: occurrence and environmental risk assessment of two WWTP effluents and their receiving bodies in the Po Valley, Italy. Sci Total Environ. 2012;438:15–25. 137. Stuart M, Lapworth D, Crane E, Hart A. Review of risk from potential emerging contaminants in UK groundwater. Sci Total Environ. 2012;416:1–21. 138. Engwall M, Hjelm K. Uptake of dioxin-like compounds from sewage sludge into various plant species–assessment of levels using a sensitive bioassay. Chemosphere. 2000;40(9–11):1189–95. 139. Wu C, Spongberg AL, Witter JD, Fang M, Czajkowski KP. Uptake of Pharma- ceutical and Personal Care products by soybean plants from Soils Applied with Biosolids and Irrigated with Contaminated Water. Environ Sci Technol. 2010;44(16):6157–61. 140. Wu C, Spongberg AL, Witter JD, Sridhar BBM. Transfer of wastewater associ- ated pharmaceuticals and personal care products to crop plants from biosolids treated soil. Ecotoxicol Environ Saf. 2012;85:104–9. 141. Wu X, Dodgen LK, Conkle JL, Gan J. Plant uptake of pharmaceutical and personal care products from recycled water and biosolids: a review. Sci Total Environ. 2015;536:655–66. 142. Gaylor MO, Harvey E, Hale RC. Polybrominated Diphenyl Ether (PBDE) Accu- mulation by earthworms (Eisenia fetida) exposed to Biosolids-, polyurethane foam Microparticle-, and Penta-BDE-Amended Soils. Environ Sci Technol. 2013;47(23):13831–9. 143. Rivier P-A, Havranek I, Coutris C, Norli HR, Joner EJ. Transfer of organic pollut- ants from sewage sludge to earthworms and barley under field conditions. Chemosphere. 2019;222:954–60. 144. Geissen V, Mol H, Klumpp E, Umlauf G, Nadal M, van der Ploeg M, van de Zee SEATM, Ritsema CJ. Emerging pollutants in the environment: a challenge for water resource management. Int Soil Water Conserv Res. 2015;3(1):57–65. 145. Tang Y, Yin M, Yang W, Li H, Zhong Y, Mo L, Liang Y, Ma X, Sun X. Emerging pollutants in water environment: occurrence, monitoring, fate, and risk assessment. Water Environ Res. 2019;91(10):984–91. 146. Naidu R, Arias Espana VA, Liu Y, Jit J. Emerging contaminants in the environment: risk-based analysis for better management. Chemosphere. 2016;154:350–7. 147. Horton AA, Walton A, Spurgeon DJ, Lahive E, Svendsen C. Microplastics in freshwater and terrestrial environments: evaluating the current understand- ing to identify the knowledge gaps and future research priorities. Sci Total Environ. 2017;586:127–41. 148. EPA EcoBox Tools by Exposure Pathways - Soil. [https://www.epa.gov/ ecobox/epa-ecobox-tools-exposure-pathways-soil]. 149. Bao L-J, Wei Y-L, Yao Y, Ruan Q-Q, Zeng EY. Global trends of research on emerging contaminants in the environment and humans: a literature assimi- lation. Environ Sci Pollut Res. 2015;22(3):1635–43. 150. Hernández F, Sancho JV, Ibáñez M, Guerrero C. Antibiotic residue deter- mination in environmental waters by LC-MS. TRAC Trends Anal Chem. 2007;26(6):466–85. 151. Boyd GR, Reemtsma H, Grimm DA, Mitra S. Pharmaceuticals and personal care products (PPCPs) in surface and treated waters of Louisiana, USA and Ontario, Canada. Sci Total Environ. 2003;311(1):135–49. 152. Petrović M, Hernando MD, Díaz-Cruz MS, Barceló D. Liquid chromatography– tandem mass spectrometry for the analysis of pharmaceutical residues in environmental samples: a review. J Chromatogr A. 2005;1067(1):1–14. 153. Richardson BJ, Lam PKS, Martin M. Emerging chemicals of concern: pharma- ceuticals and personal care products (PPCPs) in Asia, with particular reference to Southern China. Mar Pollut Bull. 2005;50(9):913–20. 154. Gray AD, Weinstein JE. Size- and shape-dependent effects of microplastic particles on adult daggerblade grass shrimp (Palaemonetes pugio). Environ Toxicol Chem. 2017;36(11):3074–80. 155. Hwang J, Choi D, Han S, Jung SY, Choi J, Hong J. Potential toxicity of polysty- rene microplastic particles. Sci Rep. 2020;10(1):7391. 156. Xing Y-F, Xu Y-H, Shi M-H, Lian Y-X. The impact of PM2.5 on the human respi- ratory system. J Thorac Disease. 2016;8(1):E69–E74. 157. Houtz EF, Sedlak DL. Oxidative Conversion as a Means of detecting precursors to perfluoroalkyl acids in Urban Runoff. Environ Sci Technol. 2012;46(17):9342–9. 158. United States Environmental Protection Agency Press Office. : EPA Announces First Validated Laboratory Method to Test for PFAS in Wastewater, Surface Water, Groundwater, Soils. In.; 2021. 159. Berg C, Crone B, Gullett B, Higuchi M, Krause MJ, Lemieux PM, Martin T, Shields EP, Struble E, Thoma E, et al. Developing innovative treatment Page 15 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 technologies for PFAS-containing wastes. J Air Waste Manag Assoc. 2022;72(6):540–55. 160. Winchell LJ, Ross JJ, Brose DA, Pluth TB, Fonoll X, Norton JW Jr, Bell KY. Pyroly- sis and gasification at water resource recovery facilities: Status of the industry. Water Environ Res. 2022;94(3):e10701. 161. Chen W-T, Haque MA, Lu T, Aierzhati A, Reimonn G. A perspective on hydrothermal processing of sewage sludge. Curr Opin Environ Sci Health. 2020;14:63–73. 162. Chen W-T, Zhang Y, Lee TH, Wu Z, Si B, Lee C-FF, Lin A, Sharma BK. Renewable diesel blendstocks produced by hydrothermal liquefaction of wet biowaste. Nat Sustain. 2018;1(11):702–10. 163. Trang B, Li Y, Xue X-S, Ateia M, Houk KN, Dichtel WR. Low-temperature miner- alization of perfluorocarboxylic acids. Science. 2022;377(6608):839–45. 164. Liu Y, Ptacek CJ, Beauchemin S, MacKinnon T, Blowes DW. Effect of compost- ing and amendment with biochar and woodchips on the fate and leach- ability of pharmaceuticals in biosolids destined for land application. Sci Total Environ. 2022;810:151193. 165. Kim Lazcano R, de Perre C, Mashtare ML, Lee LS. Per- and polyfluoroalkyl substances in commercially available biosolid-based products: the effect of treatment processes. Water Environ Res. 2019;91(12):1669–77. 166. Huber S, Moe MK, Schmidbauer JN, Hansen G, Herzke D. Emission from Incineration of Fluoropolymer materials: A literature survey. In: 2009; 2009. 167. Henry BJ, Carlin JP, Hammerschmidt JA, Buck RC, Buxton LW, Fiedler H, Seed J, Hernandez O. A critical review of the application of polymer of low concern and regulatory criteria to fluoropolymers. Integr Environ Assess Manag. 2018;14(3):316–34. 168. Aleksandrov K, Gehrmann H-J, Hauser M, Mätzing H, Pigeon D, Stapf D, Wexler M. Waste incineration of polytetrafluoroethylene (PTFE) to evaluate potential formation of per- and poly-fluorinated alkyl substances (PFAS) in flue gas. Chemosphere. 2019;226:898–906. 169. Feng M, Qu R, Wei Z, Wang L, Sun P, Wang Z. Characterization of the ther- molysis products of Nafion membrane: a potential source of perfluorinated compounds in the environment. Sci Rep. 2015;5(1):9859. 170. Schlummer M, Sölch C, Meisel T, Still M, Gruber L, Wolz G. Emission of perfluo- roalkyl carboxylic acids (PFCA) from heated surfaces made of polytetrafluo- roethylene (PTFE) applied in food contact materials and consumer products. Chemosphere. 2015;129:46–53. 171. Venkatesan AK, Done HY, Halden RU. United States National Sewage Sludge Repository at Arizona State University—a new resource and research tool for environmental scientists, engineers, and epidemiologists. Environ Sci Pollut Res. 2015;22(3):1577–86. 172. Kim Lazcano R, Choi YJ, Mashtare ML, Lee LS. Characterizing and com- paring per- and polyfluoroalkyl substances in commercially available Biosolid and Organic Non-Biosolid-Based Products. Environ Sci Technol. 2020;54(14):8640–8. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. 71 From:Anderson, Matt Sent:Tuesday, February 18, 2025 2:57 PM To:Barbara Orelo Cc:McGrath, Patrick; Lee, Tyler Subject:document Attachments:Order R3-2024-0001 (2) (1).pdf; TRE Work Plan V2 1.docx Matt Anderson Laboratory Manager Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications Toxicity Reduction Evaluation Work Plan Overview In the Waste Discharge Requirements for the City of San Luis Obispo’s Water Resource Recovery Facility (WRRF) (Order No. R3-2024-0001, NPDES No. CA0049224), the City is required to submit to the Regional Water Board a Toxicity Reduction Evaluation (TRE) Work Plan 90 days after the effective date of September 1, 2024. This document has been produced to fulfill the TRE Work Plan requirement. Prescribed Acute and Chronic Toxicity Testing The Order, in Attachment E, Section 5.1, contains acute toxicity testing requirements. These requirements specify that one acute aquatic toxicity test must be done each year, and an acute species sensitivity screening must be conducted in the first required sample collection. The acute species sensitivity screening species are identified as the Fathead Minnow (Pimephales promelas) and the Water Flea (Ceriodaphnia dubia). Acute toxicity testing is required to be performed using 100% effluent. Section 5.2, contains chronic toxicity testing requirements. These requirements specify that routine chronic toxicity is to occur monthly, and four chronic sensitivity screenings must be performed within 18 months of the effective date of the permit, with one set of screenings to be conducted in each quarter for four consecutive quarters. The discharge is subject to the determination of “Pass” or “Fail” and “Percent Effect” using the TST approach. The chronic species sensitivity screening species are identified as the Fathead Minnow (Pimephales promelas), the Water Flea (Ceriodaphnia dubia), and the Green Alga (Selenastrum capricornutum). Chronic toxicity testing is required to be performed using 100% effluent. Accelerated Monitoring and TRE Initiation As specified in Section 5.1.9, Accelerated Monitoring Requirements, “If the result of any acute toxicity tests fails to meet the single test minimum trigger (70 percent survival), and the testing meets all the TAC (Test AcceptabilityCriteria), the Discharger shall take more samples, one within 14 days and one within 21 days following receipt of the initial sample result. If any one of the additional samples do not comply with the three-sample median minimum limitation (90 percent survival), the Discharger shall initiate a Toxicity Reduction Evaluation (TRE) in accordance with section 5.4 of the MRP. If the two additional samples are in compliance with the acute toxicity requirement and testing meets all TAC, then a TRE will not be required.” As specified in Section 5.3.1, Accelerated Monitoring Requirements, “…when the chronic toxicity effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all TAC, the Discharger shall initiate accelerated monitoring to confirm the effluent toxicity. 5.3.2 The Discharger shall implement an accelerated monitoring frequency consisting of performing three toxicity tests in a six-week period following the first failed test results. 5.3.3 If implementation of the generic TRE Work Plan indicates the source of the exceedance of the effluent limitation or toxicity trigger, then only one additional test is necessary. If exceedance of the effluent limitation or toxicity trigger is detected in this test, the Discharger will continue with accelerated monitoring requirements or implement the Toxicity Identification and Toxicity Reduction Evaluations. 5.3.4 If none of the three tests indicated exceedance of the effluent limitation or toxicity trigger, then the Discharger may return to the normal testing frequency.” TRE Components The following phased TRE approach will be used to identify and reduce or eliminate the source or sources of effluent toxicity. The TRE components presented below are consistent with Toxicity Reduction Evaluation for Municipal Wastewater Treatment Plants, USEPA August 1999. 1. Information and Data Acquisition When the acute toxicity test trigger falls below 70 percent survival or chronic toxicity effluent maximum effluent limit of “Fail” is triggered, the first step will include a review of the laboratory report by the City’s Water Quality Manager, WRRF Supervisor, and contracted laboratory manager. The review will ensure that the test method requirements were met, that the coefficient of variation remains less than 40 percent, and that no other signs of sporadic mortality were observed. Following the verification of the laboratory report and bench sheets, sample collection and handling procedures will be reviewed to evaluate if the potential for sample contamination existed. If any sampling concerns are identified, appropriate corrections to sampling procedures will be implemented prior to the initiation of required accelerated monitoring. 2. Facility Performance Evaluation Operations and WRRF performance data will be reviewed from the timeframe of the toxicity sampling. Items to be reviewed will include data gathered from online instrumentation (flow, nutrient loading, nitrogen removal rates, UV disinfection trends, digester performance, and solids handling, chemical usage, polymer usage, and plant return flows). If toxicity is observed in the Water Flea, the polymer usage data from solids processing, will be closely evaluated as it has been a known toxicant to other facilities in the industry. Effluent water quality sampling for other NPDES permit constituents will be closely reviewed. If toxicity is found in the Fathead Minnow, the trending of effluent ammonia and un-ionized ammonia concentrations will be prioritized. Un-ionized ammonia is a known aquatic toxicant at 0.025 mg/L NH3-N. Total dissolved solids data will be closely reviewed with toxicity observed in the Green Alga, as elevated dissolved solids have been identified as a potential toxicant. If a treatment deficiency is causing noncompliance with an NPDES effluent limit, see note on un- ionized ammonia above, studies will be conducted to evaluate treatment modifications before proceeding further with the TRE. If the source of toxicity is not traced to the WRRF’s performance, the City will move forward with the Toxicity Identification Evaluation procedures. Additionally, a review of the operations of the wastewater collections system will be conducted. The review will include a summary of all significant industrial users or any other system anomalies that have been observed by the wastewater collections operators or Environmental Compliance Inspectors. 3. Toxicity Identification Evaluation If the City is required to move forward with the TIE, the three phases will be followed: toxicity characterization, toxicant identification, and toxicant confirmation. 4. Toxicity Source Evaluation Depending on the toxicant identified in the TIE, the wastewater collections system will be sampled and monitored using a source evaluation study. 5. Toxicity Control Evaluation Using the results from the elements one through four, the most feasible method for effluent toxicity reduction will be identified and selected for implementation. More than one control method may be required for toxicity reduction, such as implementing discharge restrictions in the collections system and additional WRRF treatment processes. 6. Toxicity Control Implementation The identified control method will be implemented, followed by continued monitoring, and ultimately ensuring the TRE objectives are met. Treatment Efficiency and Good Housekeeping Practices Good housekeeping practices are implemented to ensure efficient wastewater treatment and to meet NPDES discharge requirements. These methods are summarized below: • All hazardous chemical storage areas include secondary containment. • WRRF Operations and Maintenance track chemical usage to ensure only necessary quantities are stored on site. • The WRRF actively uses SCADA with alarms to monitor the performance of the facility. Additional process control data and NPDES regulatory analyses is performed by the City’s ELAP accredited laboratory onsite. • The City supports an Environmental Programs section that performs monitoring of Class I and Class II dischargers and complies with the Code of Federal Regulations. • The City of San Luis Obispo’s Wastewater Collections oversees the City’s Sanitary Sewer Management Plan. The responsibilities include inspections, collections system maintenance, and ongoing capital improvement projects. Chemicals Used in Facility Operation The following chemicals are used in the operation of the wastewater treatment facility. • Sodium Hydroxide • Citric Acid • Hydrogen Peroxide • Sodium Hypochlorite • Boost N Lock • Cationic and Anionic Polymers • Ferric Chloride • Carbon • Defoam 3000 72 From:forrest@stircor.com Sent:Tuesday, December 3, 2024 5:31 PM To:Lehman, Chris Subject:Stircor Biosolid Drying + Gasification Solutions Attachments:StircorOverview.pdf This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Dear Chris The rising costs of biosolid treatment and disposal is impacting municipalities across the country. Even with management of upstream sources, PFAS are expected to persist in WRRF effluent and biosolids into the foreseeable future due to legacy production. The EPA committed in their PFAS Strategic Roadmap to conduct a biosolids risk assessment for two PFAS compounds, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), in biosolids by the end of 2024. Compounding the emerging contaminant issue(s) are the evolution of land application regulations related to nutrient management with respect to both Class B and, in some instances, even Class A biosolids. Stircor presents a unique opportunity for municipal wastewater facilities to solve the consistent challenge of biosolids treatment & disposal via our comprehensive drying + gasification solution that remediates the presence of PFAS chemicals within biosolids and emissions and produces a biochar which has multiple beneficial reuse options. https://www.wwdmag.com/wastewater-treatment/press-release/55138301/company-effectively-removes-pfas-from-biosolids The Stircor solution reduces municipal operational and capital improvement budgets because Stircor owns the equipment and provides operations and maintenance (O&M) services. Our clients only pay a monthly “tip fee” for the service and there is no initial capital expense. Stircor employees take care of all operations and maintenance at no additional cost. Our Service can be up and running in as little as 12 months with the assistance of our in-house engineering team. Stircor can also be responsible for the removal of the biochar from the WWTP as part of the solution. Stircor’s exclusive partnership with Astec Industries, a U.S. based (Chattanooga TN) best in class manufacturer of thermal remediation systems, provides Stircor with the resources necessary to meet the demands of production, maintenance, and training. Municipalities spend significant operational assets on the hauling and disposal of biosolids. The potential for regulatory changes regarding emerging contaminants (PFAS/PFOA) and biosolids will only increase the complexity of biosolid management. Please let me know if there is a good time for a brief introductory discussion. 73 Regards, Forrest Forrest Porterfield, CEO 478 Craighead St. Suite 200 Nashville, TN 37204 Phone: 415-517-6265 Email: forrest@stircor.com stircor.com To help protect your privacy, Microsoft Office prevented automatic download of this picture from the Internet. Stircor was formed to address the pressing need for operators of wastewater treatment facilities to find an economically viable solution for the disposal of their biosolids that is safe from any regulatory, legal, and environmental concerns. Stircor offers drying and gasification systems that are designed specifically for the chemical makeup of biosolids. The direct drying systems can dry between 8 and 15 tons of material per hour and can be used to produce a Class A/Class A EQ product as defined by the EPA’s 40 CFR Part 503. Moreover, it produces the heat necessary to remove all hazardous materials thereby eliminating any adverse effects on crops, livestock, or water. The Stircor drying solution reduces the moisture content of the biosolid from 85% to approximately 5%-8% resulting in an 80% -90% reduction in volume. The gasification systems can process up to 8 tons per hour and remove the combustible portion of the biosolids, including PFAS/PFOAS compounds and other contaminants, leaving a biochar product which has many applications within the beneficial reuse market. The off-gases (syngas) from the gasification process are cooled, filtered for particulate, and treated in a thermal oxidizer or other applicable air pollution control equipment. The gasification process also provides the opportunity to use the off-gases for 1) supplementing energy for equipment within the drying and/or gasification process, and/or 2) generating combined heat and power. Municipalities that engage with Stircor only pay a “tipping fee” per wet ton of biosolid processed. Stircor is responsible for the installation, operation and maintenance of the dryer and gasification solution. Stircor has an exclusive partnership with Astec Industries (NASDAQ: ASTE); a recognized leader for manufacturing drying systems for industries such as concrete, soil remediation, oil fields, gasification, and biosolids. Astec (Headquartered in Chattanooga, TN), with a 50,000 square foot training facility and a parts and supply department that is second to none, gives Stircor the resources necessary to produce, operate, and service our proprietary systems. With an internal team comprised of experienced and award-winning energy efficiency professionals and engineers, Stircor was able to design a proprietary system to meet the needs of wastewater facilities. Not only does this system remove any associated risks, but it is scalable and easy to incorporate into a wide range of facility types. Stircor has a demonstration facility in Walker County, GA which can be visited by parties interested in observing our drying and gasification technology. We are capable of importing biosolids from outside municipalities for drying and gasification and subsequent testing of 1) the dried product to provide verification of Class A compliance as defined by the EPA’s 40 CFR part 503 and 2) the gasified product to confirm target contaminant destruction including PFAS/PFOAS compounds. www.stircor.com TRADITIONAL BIOSOLID PROCESSING Municipal Wastewater WASTEWATER TREATMENT PLANT Liquid Chlorine To surface water outletPrimary Treatment Secondary Treatment CORE MISSION Settling Biosolids NON-CORE: 45% OF OPERATING BUDGET Dewatering Transportation CLASS B BIOSOLID Landfill Land Application •tipping fee •transportation costs BIO S O L I D S www.stircor.com STIRCOR SOLUTION Municipal Wastewater WASTEWATER TREATMENT PLANT Liquid Chlorine To surface water outletPrimary Treatment Secondary Treatment CORE MISSION Settling Biosolids NON-CORE: 45% OF OPERATING BUDGET Dewatering CLASS A BIOSOLID/BIOCHAR Beneficial Reuse Application: revenue source Landfill at 90%reduced costs of transportation and Landfill costs STIRCOR DRYING AND GASIFICATION SOLUTION 74 From:Power, Justin Sent:Wednesday, October 23, 2024 1:22 PM To:Lee, Tyler Subject:RE: 1516 Dump Truck needed for PM90 Service Hey Tyler, While we’re doing the membrane feed testing and flows are irregular, it’s important we have the option to press from the belt press. We can’t really fill an extra bin like we discussed into today’s meeting because E&G will only pick up two bins per day. It wouldn’t be extra. Once biosolid production is back to normal it shouldn’t be an issue – the truck sat for months and months without any action. From: Lee, Tyler <tlee@slocity.org> Sent: Wednesday, October 23, 2024 12:18 PM To: WRRF_OPERATORS <WRRF_OPERATORS@slocity.org> Subject: FW: 1516 Dump Truck needed for PM90 Service Please see Chris’ request below. I know we’re using it now, but if we can have it cleaned and ready for fleet soon, that’d be great. When can I tell him we’ll have this over to them? From: Felt, Chris <cfelt@slocity.org> Sent: Wednesday, October 23, 2024 11:30 AM To: Lee, Tyler <tlee@slocity.org>; McGrath, Patrick <pmcgrath@slocity.org> Subject: 1516 Dump Truck needed for PM90 Service Hi Guys, Please let me know the soonest I can get this truck dropped off at Fleet – and extra please for it to be washed off / cleaned and safe to crawl under for a good chassis inspection and lube service!!!!! Thanks, Chris Felt Heavy Equipment Mechanic Public Works Fleet Services 25 Prado Road, San Luis Obispo, CA 93401-7314 E cfelt@slocity.org T 805.781.7046 C 805.431.0843 slocity.org Stay connected with the City by signing up for e-notifications 75 From:Anderson, Matt Sent:Thursday, October 10, 2024 7:34 AM To:Jayna K Cc:Vicki Jarvis; Prelog Requests Subject:RE: Emailing: SLO Monitoring chart.pdf page 2 Attachments:Order R3-2024-0001.pdf 76 From: Anderson, Matt Sent: Thursday, October 10, 2024 7:29 AM To: Jayna K <jaynak@fglinc.com> Cc: Vicki Jarvis <vickij@fglinc.com>; Prelog Requests <prelog@fglinc.com> Subject: RE: Emailing: SLO Monitoring chart.pdf page 2 Jayna, It looks like the column on the right was cut off. From: Jayna K <jaynak@fglinc.com> Sent: Wednesday, October 9, 2024 6:22 PM To: Anderson, Matt <manderso@slocity.org> Cc: Vicki Jarvis <vickij@fglinc.com>; Prelog Requests <prelog@fglinc.com> Subject: Emailing: SLO Monitoring chart.pdf page 2 This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Hello Matt, The second page of the list Tanner sent me says RSW (Grab) yet does not specify any locations (RSW 4,5,7,8). Was this just a generalized list based on your WDR? Thanks, Jayna -- 77 Jayna Kostura Laboratory Manager (805) 783-2940 FGL Website FGL Facebook Virus-free.www.avg.com 78 From:Anderson, Matt Sent:Tuesday, October 8, 2024 2:10 PM To:McGrath, Patrick Subject:Fw: TRANSMITTAL OF WASTE DISCHARGE REQUIREMENTS ORDER R3-2024-0001, NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT CA0049224 AND TIME SCHEDULE ORDER (TSO) R3-2024-0021 – CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY Attachments:SLO Final Order 2024-0001 and TSO 2024-0021 Transmittal Letter.pdf; Order R3-2024-0001.pdf; TSO R3-2024-0021.pdf Get Outlook for iOS From: Anderson, Matt Sent: Tuesday, October 8, 2024 7:58:10 AM To: WRRF_LAB <WRRF_LAB@slocity.org> Subject: FW: TRANSMITTAL OF WASTE DISCHARGE REQUIREMENTS ORDER R3-2024-0001, NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT CA0049224 AND TIME SCHEDULE ORDER (TSO) R3-2024-0021 – CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY From: Crable, Sarah@Waterboards <Sarah.Crable@Waterboards.ca.gov> Sent: Thursday, August 1, 2024 5:25 PM To: McGrath, Patrick <pmcgrath@slocity.org> Cc: Floyd, Aaron <afloyd@slocity.org>; Lehman, Chris <clehman@slocity.org>; Barcenas, Miguel <MBarcena@slocity.org>; Anderson, Matt <manderso@slocity.org>; alabarre@co.slo.ca.us; breely@co.slo.ca.us; Janet Parrish <Parrish.Janet@epa.gov>; Elizabeth Sablad <Sablad.Elizabeth@epa.gov>; Amelia Whitson <Whitson.Amelia@epa.gov>; Froelich, Sophie@Waterboards <Sophie.Froelich@Waterboards.ca.gov>; Waggoner, Claire@Waterboards <Claire.Waggoner@waterboards.ca.gov>; Chand, Gurgagn@Waterboards <Gurgagn.Chand@Waterboards.ca.gov>; Densmore, Jeff@Waterboards <jeff.densmore@waterboards.ca.gov>; Souza, Kurt@Waterboards <Kurt.Souza@waterboards.ca.gov>; Cunningham, Jason@Waterboards <Jason.Cunningham@Waterboards.ca.gov>; Barnard, Randy@Waterboards <Randy.Barnard@waterboards.ca.gov>; hagemann.associates@gmail.com; dchisam@smmwc.com; Steph Wald <steph@creeklands.org>; Packard, Harvey@Waterboards <Harvey.Packard@waterboards.ca.gov>; Wyatt-Mair, Arwen@Waterboards <Arwen.WyattMair@waterboards.ca.gov>; Crable, Sarah@Waterboards <Sarah.Crable@Waterboards.ca.gov>; Bishop, James@Waterboards <James.Bishop@Waterboards.ca.gov>; Lemoine, Leah@Waterboards <Leah.Lemoine@Waterboards.ca.gov>; Vance, Julie@Wildlife <Julie.Vance@wildlife.ca.gov>; Hickey, Teri@Wildlife <Teri.Hickey@wildlife.ca.gov>; thomas.coleman@noaa.gov; R9NPDES@epa.gov; WB-DIT-DMR <DMR@waterboards.ca.gov>; icis-npdes@pgenv.com; WB-DWQ-NPDES_Wastewater <NPDES_Wastewater@waterboards.ca.gov> Subject: TRANSMITTAL OF WASTE DISCHARGE REQUIREMENTS ORDER R3-2024-0001, NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT CA0049224 AND TIME SCHEDULE ORDER (TSO) R3-2024-0021 – CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Good afternoon Mr. McGrath, 79 Please see the attached transmittal letter and signed order for the recent adoption of Waste Discharge Requirements Order No. R3-2024-0001, NPDES Permit No. CA0049224, and signed time schedule order No. R3-2024-0021 for the City of San Luis Obispo Water Resource Recovery Please let me know if you have any questions. Thank you, Sarah Sarah E. Crable, P.E. Water Resource Control Engineer, NPDES Program Central Coast Regional Water Quality Control Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401 (805) 549-3706 | sarah.crable@waterboards.gov Central Coast Regional Water Quality Control Board July 30, 2024 Patrick McGrath Sent via electronic mail only City of San Luis Obispo WRRF Supervisor 35 Prado Road San Luis Obispo, CA 93401 Email: pmcgrath@slocity.org Dear Patrick McGrath: TRANSMITTAL OF WASTE DISCHARGE REQUIREMENTS ORDER R3-2024-0001, NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT CA0049224 AND TIME SCHEDULE ORDER (TSO) R3-2024-0021 – CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY, SAN LUIS OBISPO, SAN LUIS OBISPO COUNTY At its public meeting on June 20, 2024, the Central Coast Regional Water Quality Control Board (Central Coast Water Board) adopted Order R3-2024-0001, Waste Discharge Requirements for the City of San Luis Obispo Water Resource Recovery Facility, NPDES Permit CA0049224 (permit), attached. Please review the requirements carefully and note that some modifications to previous requirements are specified. Central Coast Water Board staff will also post the permit online at: http://www.waterboards.ca.gov/centralcoast/board_decisions/adopted_orders/index.sht ml Your renewed permit’s effective date is September 1, 2024. Central Coast Water Board staff will activate the permit within the California Integrated Water Quality System (CIWQS) on its effective date. Please be aware that your CIWQS permittee entry template (PET) tool may need to be updated when your new permit becomes effective. Please update the tool to reflect permit changes prior to the effective date to avoid potential late reporting violations. The following CIWQS webpage provides helpful information: https://www.waterboards.ca.gov/water_issues/programs/ciwqs/chc_npdes.html. If you need help with PET tool changes, please contact the CIWQS help desk using the contact information on the CIWQS webpage. As documented during the public process, the effective date of TSO R3-2024-0021, attached, is also September 1, 2024. The TSO provides a compliance schedule to implement changes to your pretreatment program to achieve compliance with some of the final effluent limitations contained in your permit. Patrick McGrath - 2 -July 30, 2024 Thank you for your time in assisting with the process of adopting the permit and TSO. If you have questions regarding the adopted permit or TSO, please contact Sarah Crable at (805) 549-3706 or sarah.crable@waterboards.ca.gov or Arwen Wyatt-Mair at (805) 542-4695 or arwen.wyattmair@waterboards.ca.gov. Sincerely, Ryan E. Lodge Executive Officer Attachments: Order R3-2024-0001 TSO R3-2024-0021 CC w/attachment: Aaron Floyd, Utilities Department Director afloyd@slocity.org Chris Lehman, Utilities Department Deputy Director - Wastewater clehman@slocity.org Miguel Barcenas, Utilities Department Deputy Director - Engineering mbarcenas@slocity.org Patrick McGrath, Water Resource Recovery Facility Supervisor, pmcgrath@slocity.org Matt Anderson, Water Resource Recovery Facility Lab Manager, marderso@slocity.org Aaron LaBarre, San Luis Obispo County Environmental Health, alabarre@co.slo.ca.us Blaine Reely, San Luis Obispo County Groundwater Sustainability Director, breely@co.slo.ca.us. Janet Parrish, EPA Region IX Parrish.Janet@epa.gov Elizabeth Sablad, U.S. Environmental Protection Agency, sablad.elizabeth@epa.gov Amelia Whitson, U.S. Environmental Protection Agency, whitson.amelia@epa.gov Sophie Froelich Sophie.Froelich@waterboards.ca.gov Claire Waggoner, State Water Board, Claire.Waggoner@waterboards.ca.gov Gurgagn Chand, Division of Water Quality, gurgagn.chand@waterboards.ca.gov Jeff Densmore, Division of Drinking Water, jeff.densmore@waterboards.ca.gov Kurt Souza, Division of Drinking Water, kurt.souza@waterboards.ca.gov Jason Cunningham, Division of Drinking Water, jason.cunningham@waterboards.ca.gov Randy Barnard, Division of Drinking Water, randy.barnard@waterboards.ca.gov Bradley Hagemann, General Manager, Avila Community Services District, Hagemann.associates@gmail.com Dwayne Chisam, General Manager, San Miguelito Mutual Water Company, dchisam@smmwc.com Steph Wald, Creek Lands Conservation, steph@creeklands.org Harvey Packard, Central Coast Regional Board, Harvey.Packard@waterboards.ca.gov Arwen Wyatt Mair, Central Coast Regional Board, Arwen.WyattMair@waterboards.ca.gov Sarah Crable, Central Coast Regional Board, Sarah.Crable@waterboards.ca.gov Patrick McGrath - 3 - July 30, 2024 Jennifer Epp, Central Coast Regional Board, Jennifer.Epp@waterboards.ca.gov James Bishop, Central Coast Regional Board, James.Bishop@waterboards.ca.gov Leah Lemoine, Central Coast Regional Board, Leah.Lemoine@waterboards.ca.gov Julie Vance, California Department of Fish and Wildlife, julie.vance@wildlife.ca.gov Teri Hickey California Department of Fish and Wildlife, teri.hickey@wildlife.ca.gov Thomas Coleman, National Marine Fisheries Service, thomas.coleman@noaa.gov R9NPDES@epa.gov dmr@waterboards.ca.gov icis-npdes@pgenv.com NPDES_wastewater@waterboards.ca.gov R:\RB3\Shared\NPDES\Facilities\San Luis Obispo\San Luis Obispo\2024 Order\Final Order\SLO Final Order 2024-0001 and TSO 2024-0021 Transmittal Letter.docx ECM CW-255380 STATE OF CALIFORNIA CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401 TIME SCHEDULE ORDER R3-2024-0021 REQUIRING THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY TO COMPLY WITH REQUIREMENTS PRESCRIBED IN NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT CA0049224, ORDER R3-2024-0001 The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 1.The City of San Luis Obispo (Discharger) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (Facility), a publicly owned treatment works (POTW). The Facility is located at 35 Prado Road, San Luis Obispo, San Luis Obispo County. 2.Treatment at the Facility currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four Modified Ludzack-Ettinger (MLE) bioreactors, hollowfiber membranes, and ultraviolet (UV) disinfection. The biosolids handling unit consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. 3.On June 20, 2024, the Central Coast Water Board adopted Waste Discharge Requirements Order R3-2024-0001, National Pollutant Discharge Elimination System (NPDES) Permit CA0049224. Order R3-2024-0001 regulates the discharge of tertiary treated effluent from the Facility to San Luis Obispo Creek, a water of the United States, located within the Estero Bay Hydrologic Unit. The effective date of Order R3- 2024-0001 is September 1, 2024. 4.Analysis of the Discharger’s effluent monitoring data from December 2014 through December 2022 found that the Discharger’s effluent had a reasonable potential to cause or contribute to exceedances of water quality objectives for total dissolved solids (TDS), chloride, sodium, sulfate, and molybdenum, and therefore warranted the establishment of effluent limitations for those parameters. 5.Order R3-2024-0001 prescribes the following new effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum. TSO R3-2024-0021 -2- September 1, 2024 Table 1: Final effluent limitations in Order R3-2024-0001 1Compliance is determined using a 12-month running mean. NEED FOR TIME SCHEDULE ORDER AND REGULATORY REQUIREMENTS 6.The Discharger is unable to consistently comply with the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum, which were not effluent limits in the prior permit and are new to Order R3-2024-0001. In its January 11, 2024 comment letter on draft Order R3-2024-0001, the Discharger asked the Central Coast Water Board to include an in-permit compliance schedule to allow the Discharger time to develop and implement improvements to comply with the new effluent limits. 7.State Water Resources Control Board Resolution 2008-0025, Policy for Compliance Schedules in National Pollutant Discharge Elimination System Permits (Compliance Schedule Policy), was adopted on April 15, 2008. The Policy provides that in-permit compliance schedules should only be granted when additional time is needed to complete significant compliance actions to comply with new permit limitations implementing new, revised, or newly interpreted water quality objectives or criteria in water quality standards. The Compliance Schedule Policy defines the term “new, revised or newly interpreted water quality standard” to be standards adopted by the Central Coast Water Board after September 25, 1995. (Compliance Schedule Policy, p. 3, paragraph 1 subd. (d).) The Compliance Schedule Policy defines the term “newly interpreted water quality objective or criterion in a water quality standard,” as meaning: a narrative water quality objective or criterion that, when interpreted during NPDES permit development (using appropriate scientific information and consistent with state and federal law) to determine the permit limitations necessary to implement the objective, results in a numeric permit limitation more stringent than the limit in the prior NPDES permit issued to the discharger. Newly interpreted water quality objective or criterion in a water quality standard also includes a numeric or narrative water quality objective or criterion that is implemented with a permit limitation with which the discharger cannot comply because the pollutant was newly detected in the discharger’s effluent due to new analytical techniques that were developed after the prior permit was issued. (Id., p. 3, paragraph 1 subd. (e).) 8.The Water Quality Control Plan for the Central Coastal Basin (Basin Plan) includes numeric water quality objectives for TDS, chloride, sodium, sulfate, and molybdenum. Basin Plan Table 3-5 includes numeric mean surface water quality objectives for TDS, chloride, sodium, and sulfate specific to San Luis Obispo Creek. Table 3-2 includes the numeric water quality objective for molybdenum for waters with the agricultural supply beneficial use, which applies to San Luis Obispo Creek. Parameter Units Average Annual1 Average Monthly TDS mg/L 650 Chloride mg/L 100 Sodium mg/L 50 Sulfate mg/L 100 Molybdenum mg/L 0.01 TSO R3-2024-0021 -3- September 1, 2024 These numeric water quality objectives were used in the analyses that found the Facility had reasonable potential to cause or contribute to exceedances of water quality objectives. These objectives have been part of the Basin Plan since at least 1994. 9.The Discharger is not eligible for an in-permit compliance schedule because the water quality objectives used to establish the new effluent limitations for TDS, chloride, sodium, and sulfate in Order R3-2024-0001 were not new, revised, or newly interpreted water quality standards as that term is defined in the Compliance Schedule Policy. Similarly, the Discharger is not eligible for an in-permit compliance schedule for molybdenum because the water quality objective used to establish the new effluent limitation for molybdenum in Order R3-2024-0001 was not a new, revised, or newly interpreted water quality standard as that term is defined in the Compliance Schedule Policy. Although molybdenum is newly detected in the Discharger’s effluent through monitoring requirements established in the Discharger’s previous NPDES permit, Order R3-2014-0033, the analytical techniques were developed long before the prior permit was issued. 10.Considering the foregoing analysis, a time schedule order, issued pursuant to California Water Code (Water Code) sections 13300 and 13385(j)(3), is the appropriate mechanism to allow the Discharger additional time to comply with its effluent limitations in Order R3-2024-0001. 11.Section 13300 of the Water Code states: “Whenever a regional board finds that a discharge of waste is taking place or threatening to take place that violates or will violate requirements prescribed by the regional board, or the state board, or that the waste collection, treatment, or disposal facilities of a permittee are approaching capacity, the board may require the permittee to submit for approval of the board, with such modifications as it may deem necessary, a detailed time schedule of specific actions the permittee shall take in order to correct or prevent a violation of requirements.” 12.Water Code section 13385, subdivisions (h) and (i), require the Central Coast Water Board to impose mandatory minimum penalties upon dischargers that violate certain effluent limitations. Section 13385(j)(3)(A) exempts violations of an effluent limitation from mandatory minimum penalties "where the waste discharge is in compliance with … a time schedule order issued pursuant to Section 13300, if all of the [specified] requirements are met." (emphasis added). 13.Pursuant to Water Code section 13385 subdivision (j)(3)(B)(i), the Central Coast Water Board finds that, based on effluent monitoring data, the Discharger is not able to consistently comply with the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum in Order R3-2024-0001 while new or modified control measures are implemented to increase pollutant removal efficiency or reduce the amount of these pollutants the facility receives. The effluent limitations for these pollutants are new requirements for the Discharger, and a time schedule order will allow the Discharger time to assess discharges to the collection system, collect data, perform studies, and develop additional pretreatment and control options for molybdenum and high-concentration TDS, chloride, sodium, and sulfate dischargers within the city. In addition, the new or modified control measures cannot be designed, installed, and put into operation within 30 calendar days. TSO R3-2024-0021 -4- September 1, 2024 14.The Discharger intends to carry out source control measures by implementing a pollution prevention plan, performing a source identification study, and performing a pretreatment program local limits study. During these efforts, the Discharger may be temporarily unable to comply with the Order R3-2024-0001 final effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum, and interim effluent limits are necessary. The period of this time schedule order is September 1, 2024, through August 31, 2029. 15.During the period of the time schedule order, the Discharger will continue to operate and discharge under all the limitations specified in Order R3-2024-0001 except for TDS, chloride, sodium, sulfate, and molybdenum. The Discharger will continue to report on all parameters as specified in Order R3-2024-0001. 16.Pursuant to Water Code section 13223, the Central Coast Water Board has delegated to its Executive Officer the authority to issue a time schedule order pursuant to Water Code section 13300. 17.Water Code section 13383 authorizes the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements for any person who owns or operates a publicly owned treatment works. In accordance with 40 C.F.R. sections 25.5 and 124.10 subd. (b)(1) and Water Code section 13378, the Central Coast Water Board publicly noticed this time schedule order from March 12, 2024 through April 11, 2024. No public comments were received. 18.Issuance of this time schedule order is exempt from provisions of the California Environmental Quality Act (Pub. Resources Code, section 21000 et seq.) (CEQA) pursuant to Water Code section 13389 because the adoption or modification of an NPDES permit for an existing source is statutorily exempt from CEQA, and this time schedule order only serves to implement an NPDES permit. (Pacific Water Conditioning Ass’n, Inc. v. City Council of City of Riverside (1977) 73 Cal. App. 3d 546, 555-556). Furthermore, this enforcement action is taken for the protection of the environment and as such is exempt from CEQA in accordance with section 15321, chapter 3, title 14, California Code of Regulations. MANDATORY MINIMUM PENALTIES 19.Pursuant to Water Code section 13385(j)(3), violations of the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum in Order R3-2024-0001 are not subject to Water Code section 13385 subdivisions (h) and (i) mandatory minimum penalties, provided the Discharger complies with all the requirements of this time schedule order and all the following conditions are met: a. The time schedule order specifies the actions that the Discharger is required to take in order to correct the violations that would otherwise be subject to subdivisions (h) and (i). b. The Central Coast Water Board finds that the Discharger is not able to consistently comply with one or more of the effluent limitations established in the waste discharge requirements applicable to the waste discharge for one of the reasons described in Water Code section 13385(j)(3)(B)(i)-(iv) (see Paragraph 12, supra). TSO R3-2024-0021 -5- September 1, 2024 c.The Central Coast Water Board establishes a time schedule for bringing the waste discharge into compliance with the final effluent limitation that is as short as possible and does not exceed five years in length. d.For time schedules that exceed one year from the effective date of the time schedule order, the schedule shall include interim requirements and the dates for their achievement. The interim requirements shall include both of the following: i.Effluent limitations for the pollutant or pollutants of concern. ii.Actions and milestones leading to compliance with the effluent limitation. e.The Discharger has prepared and is implementing in a timely and proper manner or is required by the Central Coast Water Board to prepare and implement a pollution prevention plan pursuant to CWC section 13263.3. This time schedule order requires the Discharger to prepare, implement, and submit a pollution prevention plan for TDS, chloride, sodium, sulfate, and molybdenum. This time schedule order satisfies the above conditions a-e. 20.This time schedule order requires the Discharger to comply with a time schedule by August 31, 2029, that will allow the Discharger to achieve full compliance with TDS, chloride, sodium, sulfate, and molybdenum final effluent limitations in Order R3-2024- 0001. 21.This time schedule order includes performance-based interim effluent limitations that are based on the 97.22 percentile for results measured from 2015 to 2023 for TDS, chloride, sodium sulfate, and molybdenum as shown in Table 3. 22.The Central Coast Water Board expects that the Discharger can maintain compliance with the interim effluent limitations included in this time schedule order. Interim effluent limitations are established when compliance with the final effluent limitations cannot be achieved by the existing Facility. Discharge of pollutants in concentrations in excess of the final limitations in the permit, but in compliance with the interim effluent limitations, can significantly degrade water quality and adversely affect the beneficial uses of the receiving stream on a long-term basis. The interim effluent limitations, however, establish an enforceable ceiling value until compliance with the final effluent limitations can be achieved. 23.If an interim effluent limit established in this time schedule order for TDS, chloride, sodium, sulfate, or molybdenum is exceeded, then the Discharger is subject to a mandatory minimum penalty for that particular exceedance as the Discharger will no longer meet the exemption in Water Code section 13385, subdivision (j)(3). IT IS HEREBY ORDERED, pursuant to California Water Code sections 13300 and 13383 and to ensure compliance with the requirements of adopted Waste Discharge Requirements Order R3-2024-0001, NPDES Permit CA0049224: 1.The Discharger shall comply with the following schedule of actions: TSO R3-2024-0021 -6- September 1, 2024 Table 2. Compliance Schedule for Total Dissolved Solids, Chloride, Sodium, Sulfate, Molybdenum (Starting September 1, 2024) Required Actions Compliance Due Dates Submit semi-annual progress and sampling results of TDS, chloride, sodium, sulfate, and molybdenum in Facility influent and effluent. Reports shall include but not be limited to: ·Discussion of overall progress in implementing the requirements of this TSO and achieving full compliance with Order R3-2024-0001 ·Results of source identification efforts and potential modifications to local limits or other pretreatment program actions ·Evaluation of compliance with final effluent limitations ·Update the Pollution Prevention Plan (PPP) section with descriptions of actions to be taken in the upcoming year beginning with the August 15, 2025 report and annually thereafter. 1st Semi-annual Report (Jul-Dec) – due by Feb 15 2nd Semi-annual Report (Jan-Jun) – due by Aug 15 Submit Pollution Prevention Plan (PPP) for TDS, chloride, sodium, sulfate, and molybdenum. Requirements for the PPP are set forth below. Submit an annual update to the PPP as a section in the semi-annual progress report describing planned actions for the upcoming year and discussing results from the previous year. PPP for calendar year 2025 due January 15, 2025 Updated PPP for 2026 due Aug 15, 2025 Updated PPP for 2027 due Aug 15, 2026 Updated PPP for 2028 due Aug 15, 2027 Updated PPP for 2029 due Aug 15, 2028 Submit Source Identification Study plan for review and approval by the Executive Officer. Requirements for the Source Identification Study are set forth below. January 15, 2025 Initiate Source Identification Study May 31, 2025 Submit Local Limits Study plan for review and approval by the Executive Officer. Requirements for the Local Limits Study are set forth below. May 1, 2026 Submit Source Identification Study results. Nov 1, 2026 Initiate Local Limits Study. Nov 1, 2026 TSO R3-2024-0021 -7- September 1, 2024 Required Actions Compliance Due Dates Submit draft Local Limits Study report, including proposed changes to local limits. Nov 1, 2027 Submit final Local Limits Study report.May 1, 2028 Achieve full compliance with final effluent limitations in Order R3-2024-0001. August 31, 2029 Pollution Prevention Plan (PPP): The PPP is an iterative plan that the Discharger will update and submit on an annual basis. The annual PPP must include the following deliverables: a.A description of new or modified methods that will be used to prevent or reduce the amount of TDS, chloride, sodium, sulfate, and molybdenum in the facility's influent and effluent during the upcoming year. Pollution prevention methods may include application and enforcement of local limits to industrial or commercial dischargers, public education and outreach, upgrades or changes to the Facility’s treatment system, or other innovative and alternative approaches to reduce discharges of TDS, chloride, sodium, sulfate, and molybdenum to and from the facility. b.An estimate of load reductions that may be attained through the methods identified above. c.A plan for monitoring and assessing the results of the pollution prevention plan. d.A discussion of the pollution prevention methods used during the previous year. e.An estimate of the load reductions that were attained during the previous year. f.Once completed, a summary of the findings of the Source Identification Study, including the monitoring results and all identified sources of TDS, chloride, sodium, sulfate, and molybdenum to and from the Facility. g.Once completed, a discussion of the findings of the Local Limits Study and a description of how the Facility’s pretreatment program will be modified. Source Identification Study: The Source Identification Study must, at a minimum, include a sampling plan consistent with the guidance in Chapter 4 of EPA’s Local Limits Development Guidance.1 The sampling must occur for a minimum of one year and must be carried out in such a manner that it is spatially and temporally representative. The Source Identification Study may include additional source identification or monitoring that the Discharger identifies as being useful in understanding and reducing all sources of pollutants in the Facility’s influent and effluent. Local Limits Study: The Local Limits Study must include a detailed re-evaluation of local limits, as described in EPA’s Local Limits Development Guidance. The Local Limits Study will use the results of the Source Identification Study to calculate or recalculate maximum allowable headworks loadings (MAHLs) for TDS, chloride, 1 https://www3.epa.gov/npdes/pubs/final_local_limits_guidance.pdf TSO R3-2024-0021 -8- September 1, 2024 sodium, sulfate, molybdenum, and any other pollutants identified as requiring further evaluation. The Discharger must use the MAHLs to develop or update local limits. 2.If the Discharger is unable to perform any activity or submit any documentation in compliance with the deadlines set forth in Table 2, the Discharger may request, in writing, an extension of the time. The extension request shall include justification for the delay and shall be submitted at least thirty days prior to the respective deadline to be considered complete and timely. 3.The following interim effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum shall be effective upon the effective date of this time schedule order and shall apply in lieu of all final effluent limitations for those pollutants in Order R3- 2024-0001. The Discharger shall maintain compliance with the following interim effluent limitations through August 31, 2029, or until the Discharger is able to come into compliance with the final effluent limitations, whichever is sooner. Table 3: Interim effluent limitations 1Compliance is determined using a 12-month running mean. 4.All reports shall be submitted under Discharger signed/certified cover letter to the California Integrated Water Quality System (CIWQS). The Executive Officer may require revisions to the form or types of data and information reported. 5.All reports required by this time schedule order shall be signed by either a principal executive officer or ranking elected official, or by a duly authorized representative of that person. A person is a duly authorized representative only if: a.The authorization is made in writing by a person described above; b.The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the owner of the regulated facility. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.); and c.The written authorization is submitted to the Central Coast Water Board. 6.Any person signing a report required by this time schedule order shall make the following certification: “I certify under penalty of perjury that this document and all attachments were prepared by me, or under my direction or supervision, following a system designed to ensure that qualified personnel properly gather and evaluate the information submitted. To the best of my knowledge and belief, this document and all attachments are true, accurate, and complete. I am aware that there are significant Parameter Units Average Annual1 Average Monthly TDS mg/L 988 Chloride mg/L 196 Sodium mg/L 196 Sulfate mg/L 157 Molybdenum mg/L 0.024 TSO R3-2024-0021 -9- September 1, 2024 penalties for submitting false information, including the possibility of fine and imprisonment.” 7.If, in the opinion of the Executive Officer, the Discharger fails to comply with any provisions of this time schedule order or fails to consistently demonstrate substantive progress towards achieving full compliance with effluent limitations in Order R3-2024- 0001, the Executive Officer may terminate this time schedule order. In that case, or if compliance with the final effluent limitations for TDS, chloride, sodium, sulfate, or molybdenum in Order R3-2024-0001 is not achieved by the full compliance dates shown above in Table 2 or the Discharger has not received an extension according to Provision 2 above, the Discharger will not be exempt from the mandatory minimum penalties for violation of those effluent limitations and may also be subject to issuance of a cease and desist order in accordance with Water Code section 13301. The Central Coast Water Board reserves its right to take any enforcement action authorized by law. 8.During the effective period of this time schedule order, the Discharger shall comply with all provisions of Order R3-2024-0001, as renewed or revised, that are not in conflict with this time schedule order. If, in the opinion of the Executive Officer, the Discharger fails to comply with the provisions of this order, the Executive Officer may refer this matter to the Attorney General for judicial enforcement, may issue a complaint for administrative civil liability, or may take other enforcement actions. Failure to comply with this order may result in the assessment of administrative civil liability of up to $10,000 per violation, per day, depending on the violation, pursuant to the Water Code, including sections 13350 and 13385. The Central Coast Water Board reserves its right to take any enforcement actions authorized by law. Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Resources Control Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Resources Control Board must receive the petition by 5:00 p.m., 30 days after the date of the order, except that if the thirtieth day following the date of the order falls on a Saturday, Sunday, or state holiday, the petition must be received by 5:00 p.m. on the next business day. Copies of the law and regulations applicable to filing petitions may be found on the internet at: http://www.waterboards.ca.gov/public_notices/petitions/water_quality, or will be provided upon request. This Order is effective on September 1, 2024. The Executive Officer may modify the time schedule in this order to permit a specified task or tasks to be completed at later dates if the Discharger demonstrates and the Executive Officer determines that the delay was beyond the reasonable control of the Discharger to avoid. ORDERED BY ___ Ryan E. Lodge, Executive Officer R:\RB3\Shared\NPDES\Facilities\San Luis Obispo\San Luis Obispo\TSO R3-2024- 0021\Draft TSO\tso_slo_R3-2024-0021.docx Place ID: 255380 80 From:Anderson, Matt Sent:Tuesday, October 8, 2024 7:58 AM To:WRRF_LAB Subject:FW: TRANSMITTAL OF WASTE DISCHARGE REQUIREMENTS ORDER R3-2024-0001, NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT CA0049224 AND TIME SCHEDULE ORDER (TSO) R3-2024-0021 – CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY Attachments:SLO Final Order 2024-0001 and TSO 2024-0021 Transmittal Letter.pdf; Order R3-2024-0001.pdf; TSO R3-2024-0021.pdf Follow Up Flag:Follow up Flag Status:Flagged From: Crable, Sarah@Waterboards <Sarah.Crable@Waterboards.ca.gov> Sent: Thursday, August 1, 2024 5:25 PM To: McGrath, Patrick <pmcgrath@slocity.org> Cc: Floyd, Aaron <afloyd@slocity.org>; Lehman, Chris <clehman@slocity.org>; Barcenas, Miguel <MBarcena@slocity.org>; Anderson, Matt <manderso@slocity.org>; alabarre@co.slo.ca.us; breely@co.slo.ca.us; Janet Parrish <Parrish.Janet@epa.gov>; Elizabeth Sablad <Sablad.Elizabeth@epa.gov>; Amelia Whitson <Whitson.Amelia@epa.gov>; Froelich, Sophie@Waterboards <Sophie.Froelich@Waterboards.ca.gov>; Waggoner, Claire@Waterboards <Claire.Waggoner@waterboards.ca.gov>; Chand, Gurgagn@Waterboards <Gurgagn.Chand@Waterboards.ca.gov>; Densmore, Jeff@Waterboards <jeff.densmore@waterboards.ca.gov>; Souza, Kurt@Waterboards <Kurt.Souza@waterboards.ca.gov>; Cunningham, Jason@Waterboards <Jason.Cunningham@Waterboards.ca.gov>; Barnard, Randy@Waterboards <Randy.Barnard@waterboards.ca.gov>; hagemann.associates@gmail.com; dchisam@smmwc.com; Steph Wald <steph@creeklands.org>; Packard, Harvey@Waterboards <Harvey.Packard@waterboards.ca.gov>; Wyatt-Mair, Arwen@Waterboards <Arwen.WyattMair@waterboards.ca.gov>; Crable, Sarah@Waterboards <Sarah.Crable@Waterboards.ca.gov>; Bishop, James@Waterboards <James.Bishop@Waterboards.ca.gov>; Lemoine, Leah@Waterboards <Leah.Lemoine@Waterboards.ca.gov>; Vance, Julie@Wildlife <Julie.Vance@wildlife.ca.gov>; Hickey, Teri@Wildlife <Teri.Hickey@wildlife.ca.gov>; thomas.coleman@noaa.gov; R9NPDES@epa.gov; WB-DIT-DMR <DMR@waterboards.ca.gov>; icis-npdes@pgenv.com; WB-DWQ-NPDES_Wastewater <NPDES_Wastewater@waterboards.ca.gov> Subject: TRANSMITTAL OF WASTE DISCHARGE REQUIREMENTS ORDER R3-2024-0001, NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT CA0049224 AND TIME SCHEDULE ORDER (TSO) R3-2024-0021 – CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Good afternoon Mr. McGrath, Please see the attached transmittal letter and signed order for the recent adoption of Waste Discharge Requirements Order No. R3-2024-0001, NPDES Permit No. CA0049224, and signed time schedule order No. R3-2024-0021 for the City of San Luis Obispo Water Resource Recovery Please let me know if you have any questions. Thank you, Sarah 81 Sarah E. Crable, P.E. Water Resource Control Engineer, NPDES Program Central Coast Regional Water Quality Control Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401 (805) 549-3706 | sarah.crable@waterboards.gov 82 From:McGrath, Patrick Sent:Friday, September 27, 2024 11:33 AM To:Jordan Lane Subject:RE: WWRF Tour Attachments:WRRF Admin.PNG 10/3 at 9am – sounds great. Looking forward to it! Patrick From: Jordan Lane <jlane@iwma.com> Sent: Wednesday, September 25, 2024 11:17 AM To: McGrath, Patrick <pmcgrath@slocity.org> Subject: Re: WWRF Tour Patrick, An on-site tour on October 3 would be fantastic - how does 9:00AM sound? We have a lot of flexibility that day so almost any time works for us if that does not. Thank you! Jordan Lane Deputy Director Office (805) 782-8530 Direct (805) 788-2796 iwma.com The Sort Report From: McGrath, Patrick <pmcgrath@slocity.org> Sent: Monday, September 16, 2024 3:34 PM 83 To: Jordan Lane <jlane@iwma.com> Subject: RE: WWRF Tour Good afternoon, Jordan, I am well, thank you! I hope you’re the same. I’d be very happy to discuss biosolids with you and your team. I’m free all afternoon on 10/1 and anytime on 10/3. I can host the tour or put together a brief presentation to come to you—you tell me what would work best. Patrick From: Jordan Lane <jlane@iwma.com> Sent: Monday, September 16, 2024 10:04 AM To: McGrath, Patrick <pmcgrath@slocity.org> Subject: WWRF Tour This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Good morning Patrick, Hope you're well! My team over here went down the deep dark hole of biosolid extraction and treatment processes at the wastewater level and I thought - who better to educate us than PM?! If you're up for a tour or even a brief presentation over here, please let me know. We'd have 5-7 staff in attendance and are shooting for some time 10/1 - 10/3 if you're available. Best, Jordan Lane Deputy Director Office (805) 782-8530 Direct (805) 788-2796 iwma.com The Sort Report 84 From:McGrath, Patrick Sent:Monday, September 16, 2024 3:35 PM To:Jordan Lane Subject:RE: WWRF Tour Good afternoon, Jordan, I am well, thank you! I hope you’re the same. I’d be very happy to discuss biosolids with you and your team. I’m free all afternoon on 10/1 and anytime on 10/3. I can host the tour or put together a brief presentation to come to you—you tell me what would work best. Patrick From: Jordan Lane <jlane@iwma.com> Sent: Monday, September 16, 2024 10:04 AM To: McGrath, Patrick <pmcgrath@slocity.org> Subject: WWRF Tour This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Good morning Patrick, Hope you're well! My team over here went down the deep dark hole of biosolid extraction and treatment processes at the wastewater level and I thought - who better to educate us than PM?! If you're up for a tour or even a brief presentation over here, please let me know. We'd have 5-7 staff in attendance and are shooting for some time 10/1 - 10/3 if you're available. Best, Jordan Lane Deputy Director Office (805) 782-8530 Direct (805) 788-2796 iwma.com The Sort Report 85 90 From:Lehman, Chris Sent:Tuesday, September 10, 2024 2:19 PM To:Bob Engel Subject:RE: E&G/SLO Contract Review Attachments:PFAS Report Short_Final_7.12.24.pdf Hi Bob, Thanks again for your time this morning. It was fun to talk shop. I am grateful for the service you’ve provided to the City and region over the past few decades. As promised, please find the PFAS study report that Greg Kester and CASA helped put together attached. Some follow ups: You were open to re-evaluating the base rate for diesel fuel surcharges. What information do you need to discuss this further? You were open to the idea of modifying the contract to include a performance discount if our facility maintains a bin-tonnage range (8-11 tons?). Would a five percent discount be reasonable? This would benefit you and give our staff something to strive towards to save us a bit of money. Looking forward to additional discussion as SLO leads regional planning meetings with 15-20 other agencies to discuss biosolids management. I am hopeful that we can all work together to maintain environmentally responsible solutions that are economical. Thanks, Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications -----Original Appointment----- From: Lehman, Chris Sent: Tuesday, August 27, 2024 4:23 PM To: Lehman, Chris; Bob Engel Subject: E&G/SLO Contract Review When: Tuesday, September 10, 2024 9:00 AM-9:50 AM (UTC-08:00) Pacific Time (US & Canada). Where: 745 Betteravia Rd, Santa Maria, CA 93455 91 Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications 1 PRELIMINARY REPORT ON THE NATIONAL COLLABORATIVE PFAS PROJECT JULY 2024 Ian Pepper, Mark Brusseau, Sarah Prasek, and Greg Kester SUMMARY The national US collaborative study has successfully resulted in the largest US data set on incidence and distribution of biosolid derived PFAS to date. Soil samples at land application sites and controls from 23 sites within 17 states have been collected at 1, 3, and 6 feet soil depths. PFAS analyses for 14 of the 23 sites have already been conducted and the remaining analyses will be concluded soon. Mean and median soil PFAS concentrations were comparatively low, and less than or equal to soil screening levels calculated for specific EPA regulated compounds in typical soils with modest soil organic carbon content of 1 to 5 percent. In addition, rapid attenuation of PFAS was shown to occur within the 0-3 feet soil depth, with additional attenuation from 3-6 feet. These data can be used for modeling the potential risk of groundwater contamination accruing to PFAS leaching through soil and the vadose zone. Wherever possible, predicted groundwater PFAS concentrations will be compared to actual groundwater concentrations at specific sites. It is anticipated that these data will be very useful to multiple states across the country by illustrating PFAS levels in soils within land application sites. This is important information that can aid in decision-making regarding potenital state bans of land application, as in Maine and most recently, in Connecticut. BACKGROUND The presence of PFAS in municipal biosolids has led to concern over the potential impacts of land application of biosolids to human health and the environment. Fear over PFAS in Maine began in 2016, following land application of industrially contaminated biosolids and paper mill sludge. The use of hay grown on impacted fields as fodder for cows resulted in milk with unacceptably high levels of PFAS. A furor concerning PFAS ensued, and on April 15, 2022, the Maine State House and Senate passed a bill that banned the use of biosolids for land application. In June 2024, Connecticut implemented a ban on land application with a simple sentence inserted into legislation (“No person shall use, sell, or offer for sale in this state as a soil amendment any biosolids or wastewater sludge that contain PFAS”) (State of Connecticut Substitute Senate Bill No. 292). This raises the question of whether a national ban could follow. In contrast, similar concerns in Michigan have led to proactive source control measures to mitigate the industrial contamination of biosolids and prevent the land application of industrially contaminated biosolids (EGLE, 2021). A critical factor limiting our ability to determine health risks from land application of biosolids is the lack of data. More sampling and monitoring data for PFAS in biosolids and soils are needed to better characterize the magnitude of PFAS originating from land application. In addition, more detailed investigations of PFAS distributions and leaching in soil are needed beyond the few that have been conducted to date. Several projects have recently started under the auspices of the EPA, USDA, and the Water Research Foundation. These studies are anticipated to add to our understanding of the impacts of land application on soil contamination, leaching potential, and uptake into plants. However, these studies are focused on a single or a select few sites. To address the limitation, a nationwide collaborative project has been initiated by the University of Arizona. This project comprises field studies conducted across broad geographic regions of the U.S. with differing 2 soils, climates, and depth to groundwater (Pepper, 2022). This project is currently in progress. In this report, we provide an update on the national collaborative project, documenting its status with respect to incidence and distribution of PFAS derived from land applied municipal biosolids. APPROACH The specific objectives of the national project in Phase 1 were: 1) To evaluate the incidence of PFAS in surface soil following long-term land application of municipal biosolids. 2) Assess the mobility (leaching) of PFAS analytes through soil. 3) Evaluate PFAS concentrations in groundwater in close proximity to land application sites to create paired datasets of soil and water PFAS concentrations. 4) To compare actual groundwater PFAS concentrations to predicted concentrations using a screening level model for PFAS leaching through soil and vadose zone. 5) Phase 2 of the project will evaluate the potential for crop uptake of PFAS following land application of biosolids. The National Collaborative PFAS Project is unique in several ways. The study is truly nationwide in scope including a variety of different soils, depths to groundwater and climates. Land application sites from across the United States have been identified, and soil samples collected from both irrigated and non-irrigated sites. Research methodology at each site is identical, allowing for direct comparison of data, and a national set of real-world field data. The study will allow for robust calibrated model development, and quantitative data will allow for risk assessments on specific land application sites. Importantly, only land application of municipal biosolids is being considered, precluding industrially contaminated biosolids. Of note, one of the sites tested turned out to be industrially impacted and therefore its data is not presented below. To ensure standardization of the research, a strict sampling and analysis protocol is being conducted at all sites. In addition, all samples are being sent to the University of Arizona Water and Energy Sustainable Technology Center (WEST) prior to being processed and sent on to the University of Arizona Laboratory for Emerging Contaminants (ALEC) for PFAS analysis. At each site, soil samples have been collected at 1, 3 and 6 feet depths from the surface. Wherever possible, groundwater in close proximity to each site has also been collected utilizing monitoring wells. Samples have been collected from across the U.S. (Figure 1) by farmers and academic researchers with land application sites with records of known biosolid loading rates. Three soil cores have been collected from control plots (no biosolids), and plots with two different loading rates of biosolids (“low” and “high”). Therefore, from each site, a total of 27 soil samples were collected: 3 plots per site x 3 cores per plot x 3 sample depths per core. Soils are being analyzed for 25 different Figure 1. States with a site(s) included in the PFAS National Collaborative Study 3 representative PFAS analytes (Table 1) utilizing USEPA Method 1633. CAS ID PFAS Analyte Acronym 375-22-4 Perfluorobutanoic acid PFBA 2706-90-3 Perfluoropentanoic acid PFPeA 307-24-4 Perfluorohexanoic cid PFHxA 375-85-9 Perfluoroheptanoic acid PFHpA 335-67-1 Perfluorooctanoic acid PFOA 375-95-1 Perfluorononanoic acid PFNA 335-76-2 Perfluorodecanoic acid PFDA 2058-94-8 Perfluoroundecanoic acid PFUnA 307-55-1 Perfluorododecanoic acid PFDoA 72629-94-8 Perfluorotridecanoic acid PFTriDA 376-06-7 Perfluorotetradecanoic acid PFTreA 375-73-5 Perfluorobutanesulfonic acid PFBS 2706-91-4 Perfluoropentanesulfonic acid PFPeS 355-46-4 Perfluorohexanesulfonic acid PFHxS 375-92-8 Perfluoroheptanesulfonic acid PFHpS 1763-23-1 Perfluorooctanesulfonic acid PFOS 68259-12-1 Perfluorononanesulfonic acid PFNS 335-77-3 Perfluorodecanesulfonic acid PFDS 757124-72-4 Fluorotelomer sulphonic acid 4:2 4:2 FTS 27619-97-2 Fluorotelomer sulphonic acid 6:2 6:2FTS 39108-34-4 Fluorotelomer sulphonic acid 8:2 8:2FTS 754-91-6 Perfluorooctanesulfonamide FOSA 31506-32-8 N-methylperfluorooctanesulfonamide N-MeFOSA 2355-31-9 2- (N-Methylperfluorooctanesulfonamido) acetic acid NMeFOSAA 2991-50-6 2-(N-Ethylperfluorooctanesulfonamido) acetic acid NEtFOSAA Table 1. PFAS Analytes for Analysis 4 RESULTS Datasets for each site will be sent individually to site personnel, and all data will be analyzed in detail in preparation for peer review publications. In this report, we present an overview of the data to date that illustrates incidence of biosolid-derived PFAS in land application plots across the US. Ultimately, data from 23 sites in 17 states will be presented. At the time of writing of this report, we provide data from 14 sites, pending analysis of soils from the other 9 sites, which should be available soon. Groundwater PFAS data will be presented along with modeling data in a subsequent report. Median soil concentrations of EPA regulated PFAS analytes are shown in Table 2. These median concentrations are derived from the analyses of Control Plots, and Low and High Biosolid Plots of the 14 sites analyzed to date. These median values are unlikely to change significantly when data from the other 9 sites are included following PFAS analyses. In contrast, minimum, maximum, and mean concentrations will almost certainly change when the remaining sites are included, and therefore we will not provide these data in this report. With respect to mobility of PFAS, substantial attenuation occurred within the 0 to 3foot soil depth range and additional attenuation by the 6foot depth. Examination of Table 2 shows that the median concentrations of PFAS analytes in the Low and High Biosolids Plots are remarkably low, and all less than 0.5ppb. Values for corresponding Control Plots are even lower. However, it is notable that these compounds are detected in Control Plots with no biosolids, and no obvious source of PFAS contamination. Compound Soil Median Concentration (ppb) EPA Drinking Water MLC (ppt) Control Low Biosolids High Biosolids PFOA 0.074 0.180 0.274 4.0 PFOS 0.023 0.419 0.470 4.0 PFHxS 0.040 0.072 0.125 10 PFNA 0.027 0.085 0.061 10 HFPO-DA (GenX) Not analyzed Not analyzed Not analyzed 10 Potential for Groundwater Contamination Evaluating the potential for PFAS in soil to impact groundwater requires characterization of the leaching potential of PFAS for the site of interest. The leaching potential in turn is a function of many factors including soil infiltration rates, evapotranspiration, soil properties including texture, the amount of precipitation or irrigation, and the specific PFAS in question (Guo et al., 2022). Overall, the risk of significant PFAS contamination of groundwater from land application of biosolids would most likely be in a scenario where biosolids contaminated with industrial inputs of PFAS are applied to a course textured soil with a shallow depth to groundwater and high rainfall or irrigation (Pepper et al., 2023). In contrast, risk of contamination would be less significant when municipal biosolids with lower PFAS content are applied to finer textured soils with large depth to groundwater. Finally note that there is greater risk of short chain PFAS leaching than longer chain PFAS. Table 2. Median Soil Concentrations of EPA Regulated Compounds Based on Analyses of 14 of the 23 National Sites 5 To quantify the risk of leaching, a modeling approach is needed. A suite of mathematical models has been developed at The University of Arizona to simulate the migration, retention, and leaching of PFAS in the vadose zone (Guo et al., 2020, 2022; Brusseau and Guo, 2023; Smith et al., 2024). The models range in complexity and associated data-input requirements. The simplest version is based on the widely used EPA dilution-attenuation factor (DAF) soil screening model (EPA, 1996). The EPA model is based on determining the maximum concentration of the target constituent in soil (the soil screening level, SSL) that would be determined to be protective of groundwater (not exceed a selected concentration such as an MCL). The standard EPA model considers retention of the constituent by sorption to soil solids as well as partitioning to the soil atmosphere. It does not consider adsorption at the air -water interface, which has been determined to be a critical source of retention for PFAS in certain conditions. Brusseau and Guo (2023) revised the EPA DAF model to incorporate adsorption at the air-water interface. The revised model can be used to calculate SSLs for any given PFAS at any land application site, provided soil characteristics at the site are known. Essentially, the SSL for a given PFAS at a given site identifies the maximum allowable soil PFAS concentration that would maintain groundwater concentrations to less than or equal to any target limit such as the new EPA drinking water MCLs of 4ppt for PFOS and PFOA. An example application of the revised DAF model is shown in Table 3. In this example, an SSL for PFOS is determined for a hypothetical soil with realistic estimates of soil characteristics such as 1.5g/cc for bulk density and 1% soil organic carbon. It is critical to note that the standard and revised DAF models have uncertainties and that the SSLs determined from the models are for screening purposes. The uncertainties and limitations are discussed in EPA (1996) and Brusseau and Guo (2023). It is als o critical to note that the calculated SSL values are for illustrative purposes only. Actual SSL values will be site specific and would need to be calculated using soil properties measured for the target site. For PFOS, calculated SSLs for the hypothetical example above can vary from 0.5ppb for a soil with 0.1% organic carbon to 6.9ppb for a soil with 5% organic carbon. From PFAS analyses conducted so far, median concentrations for Control, Low and High Biosolid Plot samples at 1 foot are lower than the corresponding theoretical SSL. Of all PFAS analytes, PFOS would appear to have the greatest incidence in soil, particularly when land application has been conducted since the 1980s when its use was more prevalent. 6 Table 3. Example Parameters and Calculated SSLs for PFOS Using the EPA Standard DAF model and the Brusseau and Guo Revised DAF model Parameter Standard Model Revised Model Notes Dilution Factor (DF) 20 20 Default, EPA 1996 Attenuation Factor (AF) 1 1 Default, EPA 1996 Dilution-Attenuation Factor (DAF) 20 20 Default, EPA 1996 Bulk density (ρb, g/cm3) 1.5 1.5 Assumed Water content (volumetric, θw, -) 0.24 0.24 Example Porosity (n, -) 0.4 0.4 Assumed Sorption coefficient (Kd, cm3/g)a 10 10 Estimated Air-water interfacial adsorption coefficient (Kaw, cm)b NA 0.12 Measured Air-water interfacial area (Aaw, cm-1)c NA 450 Estimated Distribution term (Rd, -) 63.5 288.5 Calculated Target groundwater concentration (Cgw, µg/L)d 0.004 0.004 Set value Soil Screening Level (SSL, µg/kg) 0.8 3.7 Calculated aRepresentative OC = 1%; log Koc from Brusseau, 2023a bMeasured value from Brusseau and Van Glubt, 2021 cEstimated value from Brusseau, 2023b dThe target groundwater concentration is based on EPA MCL FUTURE RESEARCH The project has already established a national network of land application plots where soil PFAS concentrations are now known. An attractive concept is to establish a similar national network of plant uptake data across the country by analyzing PFAS in crops grown on the land application plots already studied. By growing crops on these sites, plant uptake of PFAS can be evaluated on a variety of soil types under differing climate regimes. The undertaking of Phase 1 of the national study evaluating incidence of PFAS at land application sites was a massive undertaking. A Phase 2, plant uptake study nationally would also be a massive undertaking, and would require additional funding. To that end, we need to know how many entities would be willing to contribute some funding for a potential Phase 2. Could you please respond to this question so that we can determine the feasibility and scope of a Phase 2 study? Please respond regardless of whether you are or are not able to provide additional funding. Contact Information: ipepper@arizona.edu 7 REFERENCES Brusseau, M.L. (2023a ). Differential sorption of short-chain versus long-chain anionic per- and poly- fluoroalkyl substances by soils. Environments, 10, article 175. Brusseau, M.L. (2023b). Determining air-water interfacial areas for the retention and transport of PFAS and other interfacially active solutes in unsaturated porous media. Science of the Total Environment, 884, article 163730. Brusseau, M.L. and Van Glubt, S. (2021). The influence of molecular structure on PFAS adsorption at air- water interfaces in electrolyte solutions. Chemosphere 281, article 130829. Brusseau, M.L., Guo, B., 2023. Revising the EPA dilution-attenuation soil screening model for PFAS. J. Hazard. Mater. Lett. 4, 100077. EGLE 2021. https://www.michigan.gov/egle/about/organization/water-resources/biosolids/pfas-related. EPA 1996. Soil Screening Guidance: User’s Guide. Publication 9355.4-23. Guo, B., Zeng, J., Brusseau, M.L., 2020. A mathematical model for the release, transport, and retention of per-and polyfluoroalkyl substances (PFAS) in the vadose zone. Water Resour. Res. 56 (2), e2019WR026667. Guo, B., Zeng, J., Brusseau, M.L., Zhang, Y., 2022. A screening model for quantifying PFAS leaching in the vadose zone and mass discharge to groundwater. Adv. Water Resour. 160, 104102. Pepper, I.L. 2022. A national collaborative project. Personal Communication. Smith, J., Brusseau, M.L., and Guo, B. 2024. An integrated analytical modeling framework for determining site-specific soil screening levels for PFAS. Water Res., 252, 121236. State of Connecticut Substitute Senate Bill No. 292. 2024. Public Act No. 24 -59. 2024PA-00059-R00SB- 00292-PA.PDF (ct.gov) 92 From:Peter Hague <phague@co.slo.ca.us> Sent:Thursday, September 5, 2024 11:47 AM To:Lehman, Chris Subject:RE: [EXT]RE: SLO and County Chat Attachments:Env Health Risks from Biosolids, Pozzebon and Siefert.pdf This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Hey Chris, Likewise! Here’s the report. Regards, Peter Hague Director, Environmental Health Services County of San Luis Obispo 2156 Sierra Way, Suite B San Luis Obispo, CA, 93401 Office (805)781-5554 Fax (805) 781-4211 From: Lehman, Chris <clehman@slocity.org> Sent: Thursday, September 5, 2024 10:44 AM To: Peter Hague <phague@co.slo.ca.us> Subject: [EXT]RE: SLO and County Chat ATTENTION: This email DID NOT originate from County Staff. Please proceed with caution when interacting with any embedded links or attachments. Hi Peter, It was great chatting with you this morning. Congrats again on your promotion! I would be interested in reading the report you mentioned if you can share it. Regarding the attached report, shared prior, I can keep you posted as additional phases of the study progress. I’d love to be involved in the land application discussion with the County as you get that on the agenda. Best of luck with finalizing your software implimentation! Thanks, Chris Lehman Deputy Director - Wastewater Public Utilities 93 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications -----Original Appointment----- From: Lehman, Chris Sent: Thursday, July 25, 2024 4:47 PM To: Lehman, Chris; phague@co.slo.ca.us Subject: SLO and County Chat When: Thursday, September 5, 2024 8:30 AM-9:20 AM (UTC-08:00) Pacific Time (US & Canada). Where: Blackhorse Espresso & Bakery (1065 Higuera St, San Luis Obispo, CA 93401) Hi Peter, Looking forward to chatting on biosolids, and would love to chat about current issues (SSOs etc). Thanks, Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications This e-mail, and any files transmitted with it, are intended only for the person or entity to which it is addressed and may contain confidential, protected, and/or privileged material. Any review, re-transmission, dissemination or other use of, or taking of any action in reliance upon this information by persons or entities other than the intended recipient, is prohibited. If you received this in error, please contact the sender and delete the material from any computer. REVIEW Open Access © The Author(s) 2023. 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The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Pozzebon and Seifert Environmental Health (2023) 22:57 https://doi.org/10.1186/s12940-023-01008-4 Environmental Health *Correspondence: Lars Seifert LSeifert@sbcphd.org 1California Conference of Directors of Environmental Health, P.O. Box 2017, Cameron Park, CA 95682-2017, USA Abstract Background Over 40% of the six million dry metric tons of sewage sludge, often referred to as biosolids, produced annually in the United States is land applied. Biosolids serve as a sink for emerging pollutants which can be toxic and persist in the environment, yet their fate after land application and their impacts on human health have not been well studied. These gaps in our understanding are exacerbated by the absence of systematic monitoring programs and defined standards for human health protection. Methods The purpose of this paper is to call critical attention to the knowledge gaps that currently exist regarding emerging pollutants in biosolids and to underscore the need for evidence-based testing standards and regulatory frameworks for human health protection when biosolids are land applied. A scoping review methodology was used to identify research conducted within the last decade, current regulatory standards, and government publications regarding emerging pollutants in land applied biosolids. Results Current research indicates that persistent organic compounds, or emerging pollutants, found in pharmaceuticals and personal care products, microplastics, and per- and polyfluoroalkyl substances (PFAS) have the potential to contaminate ground and surface water, and the uptake of these substances from soil amended by the land application of biosolids can result in contamination of food sources. Advanced technologies to remove these contaminants from wastewater treatment plant influent, effluent, and biosolids destined for land application along with tools to detect and quantify emerging pollutants are critical for human health protection. Conclusions To address these current risks, there needs to be a significant investment in ongoing research and infrastructure support for advancements in wastewater treatment; expanded manufacture and use of sustainable products; increased public communication of the risks associated with overuse of pharmaceuticals and plastics; and development and implementation of regulations that are protective of health and the environment. Keywords Biosolids, Emerging pollutants, Land application, Microplastics, Organic contaminants, Per-and polyfluorinated alkyl substances (PFAS), Pharmaceutical and personal care products (PPCPs) Emerging environmental health risks associated with the land application of biosolids: a scoping review Elizabeth A. Pozzebon1 and Lars Seifert1* Page 2 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 Background During wastewater treatment, solids are separated from liquids and are then treated physically and chemically to produce a semisolid, nutrient-rich product known as biosolids or sewage sludge. Biosolids are typically dis- posed of through landfilling, incineration, or are used as a soil amendment (fertilizer) as they contain high con- centrations of nitrogen, phosphorous, organic carbon, and other essential elements which are beneficial for soil quality and crop production [1–3]. Although the benefit of recycling nutrients necessary for crop production and avoiding the use of energy-intensive synthetic fertiliz- ers is significant, biosolids also act as a sink for emerg- ing pollutants [3–21]. Preventing harmful exposures to these emerging pollutants when land applied remains a challenge [10, 20, 22]. The debate over safely using these human waste-derived biosolids as soil amendments is ongoing [23]. The US EPA standards for determining biosolids qual- ity are found in Title 40 of the Code of Federal Regula- tions, Part 503, but are limited in focus to the presence of ten inorganic metals (As, Cd, Cu, Hg, Mo, Ni, Pb, Cr, Se, and Zn), pathogens, and vector attractiveness. These standards do not currently contain regulatory standards or thresholds that pertain to the presence of synthetic organic contaminants [10]. And, while many organic compounds degrade easily and have minimal harmful effects on the environment, other more toxic organic contaminants meet the US EPA’s definition of being persistent and can accumulate in environment, causing harm to humans and wildlife when land applied [24]. In addition to the lack of standards for monitoring persis- tent and toxic organic contaminants in biosolids prior to land application, there are significant gaps in our under- standing of fate of these pollutants once land applied and the synergistic effects of multiple organic compounds on their distribution and transport within the environment. Moreover, the lack of efficient technologies to detect and measure these organic contaminants further reduces our ability to monitor their presence in the environment and evaluate potential impacts on human health. The volume of biosolids produced in the US is not inconsequential. The US EPA estimates that, in states where they are the permitting authority, 4.5 million dry metric tons were produced in 2021 with nearly half (43%) being land applied [25]. The remaining biosolids were landfilled, incinerated, or managed by other methods such as storage or deep well injection. The US EPA also notes that the actual amount produced could be as much as 6 million dry metric tons according to a 2018 survey conducted by the North East Biosolids and Residuals Association, because it additionally accounts for states where US EPA is not the permitting authority. The global market for biosolids was estimated at 7.5 billion USD in 2022 and is projected to reach 10.7 billion USD by 2030 [26]. This scoping review provides a landscape of the current research regarding emerging pollutants in biosolids and their fate in the environment when land applied. Poten- tial pathways of exposure, current detection methods, and possible impacts on human health and the environ- ment are discussed. The need for additional research on the fate of these pollutants and their synergistic effects in the environment along with the significant need for novel treatment methods and detection technologies for emerging pollutants is highlighted. The authors call criti- cal attention to the many knowledge gaps that currently exist to guide state and Federal regulatory frameworks for human health protection when biosolids are land applied. Methods We used an iterative process to select academic and governmental publications for inclusion in this scop- ing review. Initially, we searched databases and govern- mental websites to identify publications associated with risks to human health and the environment from the land application of biosolids using the following terms com- bined with “biosolids” or “land application of biosolids”: contaminants; organic contaminants; emerging pollut- ants; PFAS; microplastics; ground water; surface water; plant uptake; wildlife; agriculture; health risk; benefits of; pharmaceutical; personal care products; antibiotic; endo- crine disrupter; treatment technology; diagnostic tech- niques; regulations; and fate and transport. Publications were initially screened for relevance using the title and/ or abstract, and those relevant to biosolids land applica- tion were reviewed in their entirety. Authors identified through the literature search were contacted for further discussion regarding their study findings and were asked for suggestions on additional publications or resources for inclusion. References from identified publications’ citation lists were also reviewed to identify other appli- cable resources. A concerted effort was made to establish an exhaustive list of studies that were published in the last decade (between 2011 and 2022) pertaining to the land application of biosolids. Results A total of 172 scholarly research articles and governmen- tal reports were included in this scoping review (Supple- mental Fig. 1). Biosolids contain nutrients and energy which can be used in agriculture or waste-to-energy pro- cesses [11] or to replenish organic carbon in soils. How- ever, while they do contain valuable nutrients (mostly nitrogen and phosphorus), they also contain a range of synthetic organic compounds. These organic com- pounds are produced for a variety of purposes, including Page 3 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 healthcare, agriculture, and transportation, and are con- sidered indispensable for modern society [27–29]. While many organic compounds degrade easily and have mini- mal harmful effects on the environment, other more per- sistent synthetic organic contaminants have the potential to accumulate in biological matrices and can eventually cause harm to humans, wildlife, and the environment [24, 30]. Conventional wastewater treatment plants were not designed to remove these emerging pollutants and currently they are only partially effective in removing or degrading synthetic organic compounds [22, 31] result- ing in the accumulation of these pollutants in biosolids. While the risk of direct human exposure to emerging pollutants in biosolids is low and realistically may involve only those who work with biosolids such as farmers and biosolids workers [32], the risk of indirect exposure is significantly higher. Not only can the land application of biosolids result in ingestion of contaminated food-crops, animal up-take in meat or milk, and drinking water con- tamination, but it can also lead to pollutant exposure via inhalation [14, 19, 32–36]. Although exposure to indi- vidual synthetic organic pollutants in biosolids such as antimicrobials, pharmaceuticals, personal care products, surfactants and hormones would not accumulate in the food chain at concentrations that may pose a risk for human health, the sum of them could be of considerable concern [11, 37]. In this review we focus on three broad classes of emerging pollutants that pose the most significant risks to human and environmental health when biosolids are land applied to agricultural soils. Then, we explore the fate, transport, and synergistic effects of these emerging pollutants generally in the environment. Finally, we dis- cuss current diagnostic tools, treatment methods and the critical need for the development of standards to protect human and environmental health. Emerging pollutants Microplastics Microplastics, plastic pieces less than five millimeters in diameter, are typically the result of larger plastic debris degrading into smaller sizes; however some microplas- tics, such as microbeads, are manufactured at micro sizes and are often used in commercial health and beauty products [38]. Microplastics easily pass through waste- water treatment systems and approximately 70 to 98% of microplastics from liquid wastewater accumulate in bio- solids during the treatment process [20, 39–41]. Unsurprisingly, the land application of biosolids has led to agricultural soils being one of the largest natural res- ervoirs of microplastics [20]. Corradini et al. [13] evalu- ated 31 agricultural fields and found that concentration of microplastics in agricultural soils increased over time after successive land applications of biosolids. Soils with 1, 2, 3, 4, and 5 applications of biosolids had medians of 1.1, 1.6, 1.7, 2.3, and 3.5 particles g− 1 dry soil, respec- tively, demonstrating that microplastic concentrations were significantly correlated with biosolids applications. In addition, microplastics from land applied biosolids do not always remain in the soil but can also be released into the surrounding environment [3, 5]. Although the true scale of microplastic contamination has yet to be assessed, studies have repeatedly detected microplas- tics at significant distances from their source of origin and at higher elevations, indicating their susceptibility to becoming airborne [3, 42–46]. Inhalation of micro- plastics is associated with oxidative stress in lung tissues, along with general inflammatory responses in airways and bronchi and chronic exposure can lead to death [3, 47, 48]. Several other studies have also directly mea- sured microplastic concentrations suspended in air or dust, [49–52] deposited on land, [53, 54] or trapped on tree canopies [3, 55]. And because the impact of the hori- zontal and vertical intra- and inter-ecosystem spread of microplastics in the environment remains unquantified on the whole ecosystem [56], and ultimately on humans via the food chain, this area needs further investigation, particularly because microplastics are persistent in the environment and can accumulate in soil [3, 20, 57, 58]. Per- and polyfluorinated alkyl substances (PFAS) Per- and Polyfluorinated Alkyl Substances (PFAS) is a broad term for manmade aliphatic compounds with at least one carbon-fluorine (C-F) bond [14, 59]. PFAS have been mass produced since the 1940s [14, 59]; how- ever, due to environmental concerns, the production and use of long-chain (≥ 8 carbons) PFAS in North America, Europe, and Australia were voluntarily phased out in the early 2000s and replaced with shorter-chain PFAS [59, 60]. Short-chained PFAS have a lower tendency to be absorbed or leached into the soil and bioaccumulate, but are also more mobile in the environment than the lon- ger chain (C8) compounds [19, 59, 61] increasing risks of groundwater contamination and human exposure. Short- chain PFAS replacements also still persist in the environ- ment and can have adverse health and environmental effects [62–64]. A study measuring perfluoroalkyl carboxylic acid (PFCA), a subset of PFAS, in biosolids from multiple wastewater treatment plants in the US, Canada, Austra- lia, and Spain found that biosolids in the US have sig- nificantly higher amounts of PFCA compared to other countries [3]. This difference could be due to the con- tinued use of PFAS precursors in domestic and indus- trial products in the US or more sensitive methods used to detect PFAS in the reported study [3, 65]. Neverthe- less, PFAS concentrations in biosolids in the US have not Page 4 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 decreased even after long-chain PFAS use was phased out in the early 2000s [3, 10, 66]. The transformation of PFAS during wastewater treat- ment processing is of particular concern. A statewide assessment of PFAS in Michigan found that wastewa- ter industrial pretreatment programs were unable to break the C-F bond and instead transformed polyfluori- nated precursors to Perfluoroalkyl Acids (PFAAs) which are highly resistant to further degradation, effectively increasing effluent concentrations of total PFAS [14]. The stability of PFAAs, most notably perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), has earned PFAS the moniker “forever chemicals” [67, 68]. In addition to being considered a ‘forever chemical’ the fate of PFAS after being land applied is alarming. One of the earliest studies on PFAS in soil following the land application of biosolids found trace levels of perfluo- rochemicals in soil cores from biosolids-amended soils to depths of 120 cm, suggesting potential movement of these compounds within the soil profile over time [19]. A more recent study [17], investigating the impact of land applying biosolids on the occurrence, concentration, and distribution of PFAS in soils, the vadose zone, and groundwater detected PFAS in all near surface soil sam- ples (< 30 cm below ground surface), in more than 83% of soils between 30 and 90 cm below ground surface, and in the immediately underlying groundwater. PFAS, how- ever, were not detected in adjacent irrigation ditch soil samples where biosolids were not land applied. Like microplastics, PFAS have been detected in the remotest areas on earth [14, 67, 69] and high concen- trations of both microplastics and PFAS have even been detected in dust samples [52, 70]. The persistence of PFAS, with a half-life exceeding several decades, leads to complex cycling in the atmosphere, biosphere, geo- sphere, and hydrosphere (Fig. 1) further raising concerns regarding their ubiquitous distribution into human expo- sure pathways [3, 58, 71–73]. PFAS can cause adverse health impacts even at ultra- low concentrations, and have been found to bioaccumu- late in animals and humans in lung, kidney, liver, brain, and bone tissue [14, 74–82]. According to The California Department of Toxic Substances Control’s recently pub- lished chemical profile for PFAS, “Product – Chemical Profile for Treatments Containing Perfluoroalkyl or Poly- fluoroalkyl Substances for Use on Converted Textiles or Leathers” (February 2021 Final Version), PFAS exposure is associated with reproductive and developmental, liver and kidney, and immunological effects, as well as tumors in laboratory animals. In addition, inhalation of PFAS can cause acute lung toxicity and inhibit lung surfactant func- tion [3, 83, 84]. The most consistent finding from human epidemiology studies is the increase in serum cholesterol levels among exposed populations. Additionally, there are limited findings correlating exposure to infant birth weights, immune system dysfunction, cancer, and thyroid hormone disruption, and PFAS have also been linked to phytotoxicity, aquatic toxicity, and terrestrial ecotoxic- ity [84]. The Centers for Disease Control and Prevention (CDC), which monitors Americans’ exposure to PFAS as part of the National Health and Nutrition Examina- tion Survey, has detected PFAS in the blood of all people tested and notes that nearly all humans show evidence of exposure [85]. However, despite this universal exposure Fig. 1 PFAS cycle diagram depicting the movement of PFAS in natural and engineered systems [14] Page 5 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 and the potential adverse impacts to human health, there is a major data gap in our understanding of the relation- ship between exposure levels and toxicological outcomes, particularly for PFAS classes other than PFOA and PFOS [86]. The extent of environmental PFAS contamination is also not well quantified; however, based on the usage of biosolids reported by the US EPA and other study esti- mates, 1760 kg or more of PFAS could be annually depos- ited onto land directly via land application, from where they could spread into the environment via stormwater runoff, wind, and infiltration into ground water supplies [3, 10, 87]. Pharmaceuticals and personal care products Pharmaceutical and personal care products (PPCPs) are used by consumers for health and cosmetic purposes and by agroindustry to enhance the growth or health of livestock [88–90]. While not all PPCPs are persistent, many are considered “pseudo-persistent” because even though they have high transformation/removal rates this is offset by their continuous use and introduction into the environment [32, 91]. Traditional wastewater treatment plants are unable to effectively remove PPCPs [90, 92] and they can persist through wastewater treatment pro- cesses [12, 93–98]. Studies investigating the occurrence and distribution of pharmaceuticals in biosolids follow- ing wastewater treatment indicate that pharmaceuticals find their way into the environment mainly through the land spreading of biosolids [32, 99–102]. PPCPs contain chemicals that can disrupt endocrine functions and antibiotics that can lead to acquisition and spread of antibiotic resistance [12, 103]. The potential for reproductive failure caused by endocrine disrupting compounds in aquatic ecosystems (e.g., fathead min- nows, zebra fish and white sucker fish) has been exten- sively documented [12, 104–108]. However, the exposure, toxicity, and bioaccumulation of endocrine disruption compounds in terrestrial organisms has been less well studied. Preliminary evidence has suggested potential risks that are similar to those observed in aquatic species and these compounds have been implicated as potential contributors to diabetes, cancer, fertility decline, and a host of other environmental and public health issues [12]. Ultra-low nanogram per liter (ng/L) concentra- tions have exhibited impacts to both humans and aquatic organisms, including hormonal interference in fishes, genotoxicity, carcinogenicity in lab animals, endocrine disruption, and immune toxicity [29, 109, 110]. A recent nontargeted analysis using high-resolution mass spectrometry with predictive estrogenic activ- ity modeling was performed on biosolids samples from wastewater treatment plants in California to identify compounds in biosolids that present the most significant environmental barriers to its beneficial use as a soil amendment [23]. The study found that the combina- tion of predictive and in vitro estrogenicity with non- targeted analysis led to confirmation of estrogen-active contaminants in California biosolids and highlighted the importance of evaluating both agonistic and antagonis- tic responses when evaluating the bioactivity of complex samples. While these findings are compelling, it should be noted that the full spectrum of chemicals that have estrogenic activity and/or can affect the estrogen recep- tor signaling pathway and subsequent downstream physi- ological events remains largely unexplored [23]. According to the World Health Organization, the big- gest threat to global health, food security, and devel- opment is antibiotic resistance, of which PPCPs are a contributor. An increasing number of infections and diseases are becoming difficult to treat, as antibiotics used to treat them become less effective [29, 111, 112]. Our ability to effectively treat infections is hindered by the proliferation of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB), which encode various mechanisms conferring drug resistance [15]. A study by Law et al. (2021) found that the spread of ARGs among bacteria is largely driven by the horizontal trans- fer of mobile genetic elements (MGEs) such as plasmids (Fig. 2) [18]. And they indicate that plasmids are impor- tant vectors of horizontal gene transfer and are capable of transferring multiple ARGs simultaneously, provid- ing multidrug resistance to the recipient bacteria in one event. Enrichment of soils with ARGs following the appli- cation of biosolids has also been reported [8, 113–115] and given the frequent use of biosolids as fertilizer, their ability to actively transfer resistance genes to pathogens by means of these plasmids is concerning and needs to be further investigated [18]. Wolters et al. [116] also found that disinfectants, heavy metals (including Arsenic as a metalloid), and antibiotics can enhance horizontal gene transfer at sub-inhibitory concentrations. The authors of this study also indicate that use of biosolids as organic fertilizer is contentious – on the one hand, they pro- vide valuable fertilization while on the other they intro- duce pollutants that likely affect the soil resistome and increase transferability of ARGs, reinforcing the need for further investigation. A study by Sherburne et al. (2016) also found con- centrations of Triclocarban (TCC) and Triclosan (TCS) measured in each trophic level of a terrestrial food web at an agricultural field that had biosolids land applied over a seven-year period. The study investigated a terres- trial food web encompassing biosolids, soil, earthworms (primary consumer), deer mice (Peromyscus manicula- tus, secondary consumer), European starlings (Sturnus vulgaris, a secondary consumer of invertebrates), and American kestrels (Falco sparverius, a tertiary consumer Page 6 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 of rodents, small birds, and invertebrates) at the biosolids experimental site. The results were compared to the same type of sample results obtained from another agricultural reference site that did not have biosolids land applied and found that antimicrobials were detected in soil as well as in primary (earthworms), secondary (deer mice, star- lings), and tertiary (kestrels) consumers. Moreover, con- centrations were higher in biosolids (TCC − 1026 − 1472 ng/g wet weight (ww) and TCS − 1114 − 1350 ng/g ww), soil (TCC 14.8 − 27.3 ng/g ww and TCS − 2.7 − 4.4 ng/g ww), deer mice livers (TCC: 12.6 − 33.3 ng/g ww), and starling eggs (TCC: 15.4 − 31.4 ng/g ww) at the experi- mental site than at the reference site. Furthermore, a recent study by Hung et al. [15], found that the biosolid samples contained significantly higher levels of selected ARGs than the raw agricultural soils (p < 0.05). Average relative abundances of (intI1, sul1, blaSHV, and ermB) genes were significantly higher in biosolid-amended soils compared to nearby agricultural soils (p < 0.05). A spatial interpolation analysis of relative gene abundances (of intI1, sul1, sul2, and tetW) across the studied area indicated directional trends towards the northwest and southeast directions, highlighting possible airborne spread. Hung et al. concluded that this study brings attention to the need to redefine our antimicrobial standards in soils in terms of public health, in addition to highlighting the importance of considering relatively unstudied transmission routes, such as groundwater and air, when dealing with the current worldwide antibiotic resistance crisis [15]. Aging, degradation, and synergistic effects of emerging pollutants The actual fate of organic pollutants in soil is governed by many different factors including soil characteris- tics, compound properties, and environmental factors such as temperature, precipitation, and the ability of soil microbes to degrade the compound [32, 117]. Emerging Fig. 2 Biosolids from WWTPs used as agricultural soil fertilizer contain bacteria (green rectangles) with resistance plasmids (orange circles). These biosol- ids can spread the resistance plasmids further, and through direct or indirect routes transfer to human pathogen and commensal bacteria (red rectangles with black spikes) [18] Page 7 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 pollutants have now also been spread into areas where biosolids have not been land applied because of their per- sistence during long distance transport and bioaccumu- lation. For example, land applied biosolids enriched with longer chain PFAS can be adsorbed to microplastics or dust and become airborne [3]. Biosolids can also release fine particles or colloids when subjected to natural drying and freeze thaw cycles, which can carry PFAS to subsur- face and ground water [3, 118, 119]. The fate of emerging pollutants in biosolids after land application can vary based on physicochemical proper- ties of the organic compound, the treatment process used to generate the biosolids, and soil properties (e.g., pH and organic carbon), as well as climate [120–125]. Organic compounds present in biosolids, however, can be mobi- lized during rainfall events following land application, and have been detected in both the dissolved phase, as well as associated with suspended particulates [126, 127]. Gottschall et al. reported the presence of PPCPs in agri- cultural tile drainage and ground water after application of dewatered biosolids [128]. While Gottschall et al., indicate that the dissipation of many PPCPs in biosolids- amended soils occurs within the first few months after application, some PPCPs, including those in biosolid aggregates incorporated into soil, can still be detected for more than one year following biosolids land application. Emerging pollutants can also be transformed during degradation into products that have similar biological activity or can have greater toxicity than the parent com- pound [129, 130]. Macherius et al. reported the forma- tion of triclosan conjugates in carrot cell cultures such that the quantity of conjugates exceeded the amount of parent triclosan by a factor of five [131]. Mordechay et al., reported extensive epoxidation of carbamazepine in the leaves of multiple plant species exposed to the pharmaceutical [132]. More information is needed on the importance of the production of contaminant trans- formation products after environmental release of these compounds, and the potential for further transloca- tion of pollutants and transformation products beyond plants, especially among nontarget organisms consum- ing exposed plants [133]. In addition, further study of the role of environmental factors such as rhizosphere microorganisms may play in uptake and transformation of pharmaceuticals in the environment is required [133]. Another factor widely recognized as affecting the bio- availability of organic contaminants in soil is residence time. As soil pollutant contact time increases, pollutant bioavailability and extractability decrease [32, 117]. Dur- ing aging, pollutants slowly diffuse into the soil matrix via isomorphic dissolution reactions, thus becoming increas- ingly inaccessible for biodegradation and bioaccumula- tion [32]. Weathering and aging have been reported to result in decreased toxicity and bioavailability of many soil-applied chemicals [32, 134]. And since long-term aging reactions modify organic contaminants’ availabil- ity and toxicity over time, they are important in human and ecological risk assessments and the development of soil quality standards [32]. For instance, sediments can become potentially bioavailable to benthic organisms, and if the level of bioaccumulation is high, they can gen- erate acute and chronic exposure and spread to higher trophic levels [29, 135–137]. Recalcitrant organic con- taminants have been found to uptake into plant roots and vegetable crop plants [138–141] and earthworms that can in turn be consumed by other predators in the food chain [142, 143]. Vasilachi et al. further indicated that if emerging pol- lutants are in mixtures, the toxic effects can be cumula- tive and generate synergistic or antagonistic interactions, leading to the so-called “cocktail effect”, so that the diffi- culty of risk analysis increases [29, 144–146]. Microplas- tics, for instance, are characterized as being hydrophobic, which makes them inclined to attach to the solid matrix [20, 147]. Studies have also confirmed a high concen- tration of both and PFAS in dust samples [52, 70]. As a result of these characteristics, the application of biosol- ids as a fertilizer on agricultural fields may release pol- lutants such as microplastics and PFAS into the air and pose an inhalation risk because they are more susceptible to suspension by wind than natural soil particles [3]. In this context, the authors indicate that the precaution- ary principle needs to be applied consistently to ensure a clean and healthy environment for future generations, which is also why further studies on the risks induced by emerging pollutants, due to their specific environmental behavior, toxicity, and impacts on the environment and human health become essential [29]. Figure 3 illustrates the relationships between potential exposure pathways and potential ecological receptors after a source, such as biosolids, releases a stressor to soil. Evolution of diagnostic techniques Although some emerging pollutants and their transfor- mation by-products have existed in the environment for years, their qualitative and quantitative occurrence have been analyzed only recently [27, 29, 101, 149]. New ana- lytical techniques have made it possible to detect and quantify approximately 3000 biologically active chemi- cal compounds in the environment [29, 150–153]. How- ever, efficient and rapid methods for detection in biosolid matrices are lacking. Detection methods used to count microplastics in bio- solids may underestimate or even exclude many micro- plastics smaller than 10 μm - the fraction that could pose a greater risk for human and animal health [3, 5, 154– 156]. Thus, it is critical to develop a simple, rapid method Page 8 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 of isolating and quantifying microplastics from environ- mental samples. Hutchinson et al. demonstrated through improvements to the analytical method that levels of PFAS in biosolids are significantly higher than historically understood, indi- cating that the land application of biosolids could result in sensitive environments being exposed to PFAS at levels much higher than previously anticipated [16]. The total oxidizable precursor (TOP) assay, originally published by Houtz and Sedlak [157], has been widely used as an esti- mate of the total PFAA content of a sample, particularly in wastewater and biosolid matrices; however, it appears this method is failing to adequately digest all the PFAA precursors present in the sample [16]. Still, progress is being made in this arena. The US EPA and the Depart- ment of Defense are working to complete a multi-labo- ratory validation study of a new Method 1633 to test for 40 unique PFAS compounds in wastewater, surface water, ground water, soil, biosolids, sediment, landfill leachate, and fish tissue [158]. Future work is also needed to investigate additional compounds and transformation products that have estro- genic characteristics using non-targeted chemical analy- sis in conjunction with effects-directed analysis to gain a more comprehensive understanding of endocrine active consumer product chemicals that persist beyond their intended use in consumerism and enter the environment upon ultimate disposal [12]. Biosolids treatment to remove emerging pollutants Research and experiments into new technologies, or a combination of technologies are needed to reduce the risk wastewater and biosolids can have on the environment and human health as conventional waste- water treatment plants are, in principle, not designed to remove emerging pollutants [22, 31]. In April of 2020, the United States Environmental Protection Agency (US EPA) formed the PFAS Innovative Treatment Team to explore innovative tools and methods for destroying all the carbon fluorine (C-F) bonds in PFAS-containing waste [159]. The work resulted in improved understand- ing and advancement of four innovative non-combustion technologies to supplement ongoing EPA research into PFAS treatment. These technologies are electrochemical oxidation (EO), supercritical water oxidation (SCWO), mechanochemical degradation, and gasification and pyrolysis [160]. Berg et al. describes EO as being used to oxidize pol- lutants by means of passing an electrical current through a solution [159]. They describe that the electronegativity and electron affinity of fluorine allows the C-F bond to be broken and the fluorine atoms reduced when a high over- potential is applied to a solution. Their review of SCWO indicates that preliminary studies on biosolids treatment have shown strong reductions in PFOS and PFOA levels in the processed effluent. They also indicate that suffi- ciently dewatered sludge, or wet sludge dried by addition of co-milling agents, would be applicable to treatment in a mechanochemical degradation system. However, they indicate no such tests with PFAS have been identified in the literature. They further indicate that PFAS test- ing on a biosolids pyrolysis system was repeated in a test commissioned by the PFAS Innovative Treatment Team confirming high levels of degradation of the target PFAS compounds analyzed in the feed. Research to evaluate Fig. 3 The diagram illustrates relationships between potential exposure pathways and potential ecological receptors after a source releases a stressor to soil [148] Page 9 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 these promising technologies for PFAS destruction are ongoing. Chen et al. indicates that hydrothermal processing (HTP), including hydrothermal carbonization (HTC) and hydrothermal liquefaction (HTL), is a promising method to sustainably manage biosolids because it can convert it into useful products while mitigating the environmental risks of biosolids simultaneously [161]. They describe that products from HTP are normally biocrude oil, aqueous products (containing fertilizer precursors), and hydrochar. The authors also indicate that HTC has been extensively used for phosphorus recovery, while HTL can effectively remove constituents of emerging concern. They go on to indicate that energy analysis of HTP indi- cates that HTP has a 11-fold higher energy recovery than landfilling [162]. Low temperature mineralization of perfluorocarbox- ylic acids is also being experimented with. Trang et al. found that perfluoroalkyl carboxylic acids (PFCAs) could be mineralized through a sodium hydroxide-mediated defluorination pathway [163]. Their study found that PFCA decarboxylation in polar aprotic solvents produced reactive perfluoroalkyl ion intermediates that degraded to fluoride ions (78 to ~ 100%) within 24 h. The study also indicates that degradation was observed for branched perfluoroalkyl ether carboxylic acids. They surmised that this may then inform the development of engineered PFAS degradation processes and facilitate expanding this reactivity mode to PFAS with other polar head groups. For perspective, and as described by Vasilachi et al., source reduction and substitution of emerging pollutants with products having lower toxicity and easier removal from water have played an important role in reducing the impact of emerging pollutants on the environment and human health [29]. Amending biosolids with biochar or wood chips has been demonstrated to significantly enhance the degradation and/or retention (sorption) of target total and(or) leachable pharmaceuticals [164]. However, one should keep in mind that the solution to pollution should not always be dilution, so efforts to treat biosolids to remove contaminants of potential risk to health and the environment should continue to be pursued, particularly due to the demonstrated bioper- sistence of many of these synthetic organic chemicals. Related to PFAS, another study of commercial biosol- ids from the U.S. and Canada found that while thermal hydrolysis had no apparent effect on the PFAA concen- tration, heat treatment and composting increased PFAA concentrations (especially PFHxA) via the degradation of precursors [165]. Only blending with PFAS-free material decreased the concentration of PFAAs in the commercial biosolids, by diluting it. With millions of tons of biosol- ids being land applied annually, dilution cannot be a sus- tainable or a long-term treatment solution to removing contaminants that persist and bioaccumulate in the environment. The California Department of Toxic Substances Control chemical profile for PFAS, “Product – Chemical Profile for Treatments Containing Perfluoroalkyl or Polyfluoroal- kyl Substances for Use on Converted Textiles or Leathers” (February 2021 Final Version) indicates that intentional or accidental combustion of PFAS forms hazardous chemicals [84]. For instance, the combustion of various fluorinated polymers can result in emissions of C3-C14 PFCAs, ozone-depleting substances such as chlorofluo- rocarbons, and greenhouse gases such as fluorocarbons when fluoropolymers are combusted at temperatures representative of municipal incinerators [166]. During incineration at temperatures above 450 °C, Polytetrafluo- roethylene (PTFE) (aka Teflon) also forms additional haz- ardous substances including the ultra-short-chain PFAA tetrafluoroacetic acid and hydrofluoric acid (HF) [166, 167]. Moreover, an industry-sponsored study in a rotary kiln test facility simulating municipal incinerators found that PTFE polymer pellets begin to decompose at around 500˚C, and by approximately 650˚C they completely con- vert to HF gas and F-containing ash, with no significant PFAA emissions [168]. Other authors have reported that at lower temperatures, as could occur during acciden- tal landfill fires, fluoropolymers such as PTFE can break down into PFCAs, including PFOA [169, 170]. In this regard, future technologies need to be both effective and environmentally-friendly treatments, capa- ble of removing the widest possible spectrum of emerg- ing pollutants, with low energy consumption and capital expenditures. And the efficiency of the treatment must be adjustable to emerging pollutants concentrations in an aquatic environment to make it possible to recover the treated water [29]. Monitoring and regulations The lack of standards and regulations for the emerging pollutants discussed in this review are due, in part, to lack of available data on the effects of chronic exposure on human health. This underscores the need for complete epidemiological and toxicological studies, in addition to the development of better treatment technologies, and standardized diagnostic testing methods for monitoring emerging pollutants in biosolids. Additionally, systematic approaches are needed to identify and prioritize pollut- ants of emerging concern [10, 171]. A complete ban on land application would not only place a heavy burden on public municipalities but could also lead to unintended consequences [172]. Recently, two states in the US have adopted regula- tions relating to the presence of PFAS substances in biosolids. In 2021 under an interim strategy, Michigan began prohibiting the land application of industrially Page 10 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 impacted biosolids containing more than 150 parts per billion (ppb) of PFOS and requires testing of biosolids prior to land application. On April 15, 2022, the Maine state House and Senate both passed a bill (LD 1911) that would ban the use of biosolids that contain PFAS in land applications, unless it can be shown that the biosolids are PFAS free. On the national level, in a move toward regulation of PFAS, EPA Administrator Michael S. Regan announced the Agency’s PFAS Strategic Roadmap on October 18, 2021. The roadmap charts an approach to addressing PFAS with EPA’s Commitments to Action steps that take place between 2021 and 2024. In addition, the EPA’s Office of Water developed a Biosolids Chemical Risk Assessment and Biosolids Screening Tool (BST) with an accompanying User Guide to identify pollutants, path- ways, and receptors of greatest interest and to inform decisions regarding the need for refined risk assessment of land-applied biosolids. In late 2021, the US EPA also selected a Science Advisory Board to review and pro- vide input on the overall risk assessment approach and on the scientific credibility and usability of the BST. But these actions have not yet translated into protective stan- dards for public health with respect to biosolids land application. Discussion From a regulatory standpoint, there is an urgent and crit- ical need to modernize environmental health standards that pertain to the land application of biosolids. Current US EPA regulatory standards have not been updated since 1993 and do not take the emerging contaminants described in this review into account. The revision of these standards should be risk-based, prioritizing emerg- ing pollutants that are persistent and can bioaccumu- late. Support should be provided for the development of novel technologies to better treat biosolids to remove the contaminants of concern before they are land applied and novel methods for recycling or reuse of these pollut- ants should be explored. However, these changes require political will and collaboration among state and federal agencies to prioritize new policies and regulations. Ongoing development of analytical methodologies for identifying emerging contaminants in soil, water, waste, and other media should be a priority of relevant regula- tory agencies. Of note, Hutchinson et al. indicate that a standardized analytical methodology is needed to protect environmental assets from PFAS contamination from land-applied biosolids [16]. Inconsistencies between cur- rent testing methods used to detect and measure emerg- ing pollutants, likely underestimate concentrations of these pollutants in receiving matrices, especially where published quantification methods are adapted to bio- solids but not the receiving matrix. At the time of this writing, the US EPA is developing a new standardized testing methodology; however, the authors’ conclusions remain relevant as prior studies have not captured a com- plete picture of the extent and impact of contamination. More research is also needed to assess the long-term human health risks from exposure to emerging pollut- ants. The ecological risks of microplastics in agricultural soils urgently need to be assessed with respect to animals, plants, and microorganisms inhabiting soils and humans involved via the food web. Additionally, future studies should measure microplastics and associated PFAS in dust from biosolids and quantify exposure risks via inha- lation. Studies evaluating the factors that contribute to the fate of emerging pollutants must be conducted to bet- ter understand exposure routes and the risks of surface and ground water contamination with these pollutants. Lastly, effective communication to the public on the significance of pharmaceutical ingestion and personal care product use and the resulting environmental effects due to runoff from agricultural land may help to put pressure on decision-makers and create an awareness of unwarranted excessive use of these products [32]. This also presents an opportunity to promote use of more sus- tainable products to reduce the volume of contaminants that are released to the environment via wastewater infrastructure pathways. Conclusion Humans are being continuously exposed to the emerg- ing pollutants described in this review and a concerted effort should be made to mitigate these exposures and risks among the general public, policymakers, wastewa- ter treatment plant operators, and farmers, in terms of raising awareness, controlling the sources, and establish- ing a reasonable regulatory risk level for biosolids reuse. As a society we must also promote the use of more envi- ronmentally sustainable products that can be flushed into the environment. Research indicates that biosolids contain a complex mixture of contaminants, and investment in effective treatment and diagnostic technologies are essential for detecting and reducing the presence of contaminants so the benefits of biosolids related to carbon sequestra- tion and soil health can be fully realized. We should reconsider the continued land application of biosolids in this seemingly endless loop of spreading contaminants into our environment, and we should most certainly not continue to do it in the name of recycling, climate change, and soil health. Instead, efforts need to be pur- sued to work within the current system to better com- municate and act upon the human health risks in order to achieve desired public health outcomes. Significant funding and support for upgrading wastewater treatment Page 11 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 infrastructure are also needed to address these issues of today in order to better prepare for a safer tomorrow. A final note to ponder as we consider this issue. Biosol- ids, in their current form, have often been referred to as an organic waste to be recovered and recycled. But given the presence of contaminants that originate from both domestic and industrial wastewater sources, is that really the appropriate designation in law or regulation? As a society, if we fail to take definite policy actions to mod- ernize environmental standards that pertain to the land application of biosolids, and continue to land apply layer upon layer of these complex mixtures of pollutants to our soil without adequate public health protections in place, and without regard to the long-term environmental con- sequences, we may potentially cause irreversible damage to the very soils we use to grow our food and to our sur- face and ground water that sustain life. Supplementary Information The online version contains supplementary material available at https://doi. org/10.1186/s12940-023-01008-4. Supplemental Fig. 1. PRISMA Flow Diagram Acknowledgements This literature review was prepared with the support of the California Conference of Directors of Environmental Health (CCDEH) Executive Committee and Executive Director Justin Malan; the CCDEH Water and Land Policy Committee Chaired by Vicki Jones, REHS; and the CCDEH Solid Waste Resource and Recovery Committee co-chaired by Lars Seifert, REHS and Charles Genkel, REHS. CCDEH would also like to thank Chad A. Kinney, Ph.D. who assisted with peer review. Authors’ contributions E.P. provided conceptualization of the literature review; E.P. collected and reviewed the scientific literature and wrote the manuscript text; and L.S. contributed editorially to the structure of the manuscript and supported the implementation of the literature review. All authors reviewed the manuscript. Funding Not applicable. No funding was received to assist with the preparation of this manuscript. Data Availability Not applicable. All literature cited is available at the reference provided. Declarations Competing interests The authors have no conflicts of interest to declare that are relevant to the content of this article. All authors certify that they have no affiliations with or involvement in any organization or entity with any financial or non-financial interest in the subject matter or materials discussed in this manuscript. E.P. is a recently retired County of San Luis Obispo Environmental Health Director, and L.S. is employed as the Environmental Health Services Director for Santa Barbara County, California. Authors are both participating members in the California Conference of Directors of Environmental Health, a 501(3)c non- profit professional association. Ethics approval and consent to participate Not applicable. Consent for publication Not applicable. Received: 17 October 2022 / Accepted: 14 August 2023 References 1. Broderick SR, Evans WB. Biosolids promote similar plant growth and quality responses as conventional and slow-release fertilizers. HortTechnology hortte. 2017;27(6):794–804. 2. Shober AL, Stehouwer RC, Macneal KE. On-Farm Assessment of Biosolids Effects on Soil and Crop tissue quality. J Environ Qual. 2003;32(5):1873–80. 3. Borthakur A, Leonard J, Koutnik VS, Ravi S, Mohanty SK. Inhalation risks of wind-blown dust from biosolid-applied agricultural lands: are they enriched with microplastics and PFAS? Curr Opin Environ Sci Health. 2022;25:100309. 4. Crossman J, Hurley RR, Futter M, Nizzetto L. Transfer and transport of micro- plastics from biosolids to agricultural soils and the wider environment. Sci Total Environ. 2020;724:138334. 5. Koutnik VS, Alkidim S, Leonard J, DePrima F, Cao S, Hoek EMV, Mohanty SK. Unaccounted microplastics in Wastewater Sludge: where do they go? ACS ES&T Water. 2021;1(5):1086–97. 6. Mohajerani A, Karabatak B. Microplastics and pollutants in biosolids have contaminated agricultural soils: an analytical study and a proposal to cease the use of biosolids in farmlands and utilise them in sustainable bricks. Waste Manag. 2020;107:252–65. 7. Benítez E, Romero E, Gómez M, Gallardo-Lara F, Nogales R. Biosolids and Biosolids-ash as sources of Heavy Metals in a plant-soil system. Water Air Soil Pollut. 2001;132(1):75–87. 8. Munir M, Xagoraraki I. Levels of Antibiotic Resistance genes in Manure, Biosol- ids, and fertilized soil. J Environ Qual. 2011;40(1):248–55. 9. Harrison EZ, Oakes SR, Hysell M, Hay A. Organic chemicals in sewage sludges. Sci Total Environ. 2006;367(2):481–97. 10. Venkatesan AK, Halden RU. National inventory of perfluoroalkyl substances in archived U.S. biosolids from the 2001 EPA National Sewage Sludge Survey. J Hazard Mater. 2013;252–253:413–8. 11. Paz-Ferreiro J, Nieto A, Méndez A, Askeland MP, Gascó G. Biochar from Biosol- ids Pyrolysis: a review. In: Int J Environ Res Public Health vol. 15; 2018. 12. Black GP, Anumol T, Young Thomas M. Analyzing a broader spectrum of endocrine active organic contaminants in sewage sludge with high resolu- tion LC-QTOF-MS suspect screening and QSAR toxicity prediction. Environ Science: Processes Impacts. 2019;21(7):1099–114. 13. Corradini F, Meza P, Eguiluz R, Casado F, Huerta-Lwanga E, Geissen V. Evidence of microplastic accumulation in agricultural soils from sewage sludge dis- posal. Sci Total Environ. 2019;671:411–20. 14. Helmer RW, Reeves DM, Cassidy DP. Per- and Polyfluorinated Alkyl Substances (PFAS) cycling within Michigan: contaminated sites, landfills and wastewater treatment plants. Water Res. 2022;210:117983. 15. Hung W-C, Miao Y, Truong N, Jones A, Mahendra S, Jay J. Tracking antibiotic resistance through the environment near a biosolid spreading ground: resistome changes, distribution, and metal(loid) co-selection. Sci Total Envi- ron. 2022;823:153570. 16. Hutchinson S, Rieck T, Wu X. Advanced PFAS precursor digestion methods for biosolids. Environ Chem. 2020;17(8):558–67. 17. Johnson GR. PFAS in soil and groundwater following historical land applica- tion of biosolids. Water Res. 2022;211:118035. 18. Law A, Solano O, Brown CJ, Hunter SS, Fagnan M, Top EM, Stalder T. Biosolids as a source of antibiotic resistance plasmids for commensal and pathogenic Bacteria. Front Microbiol 2021, 12. 19. Sepulvado JG, Blaine AC, Hundal LS, Higgins CP. Occurrence and fate of Per- fluorochemicals in Soil following the Land Application of Municipal Biosolids. Environ Sci Technol. 2011;45(19):8106–12. 20. Liu H, Wang Z, Nghiem LD, Gao L, Zamyadi A, Zhang Z, Sun J, Wang Q. Solid- embedded microplastics from Sewage Sludge to Agricultural Soils: detection, occurrence, and impacts. ACS ES&T Water. 2021;1(6):1322–33. 21. Sherburne JJ, Anaya AM, Fernie KJ, Forbey JS, Furlong ET, Kolpin DW, Dufty AM, Kinney CA. Occurrence of Triclocarban and Triclosan in an agro-ecosystem following application of Biosolids. Environ Sci Technol. 2016;50(24):13206–14. Page 12 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 22. Koumaki E, Noutsopoulos C, Mamais D, Fragkiskatos G, Andreadakis A. Fate of emerging contaminants in high-rate activated Sludge Systems. In: Int J Environ Res Public Health vol. 18; 2021. 23. Black GP, He G, Denison MS, Young TM. Using estrogenic activity and Nontar- geted Chemical Analysis to identify contaminants in Sewage Sludge. Environ Sci Technol. 2021;55(10):6729–39. 24. Steele JC, Meng X-Z, Venkatesan AK, Halden RU. Comparative meta-analysis of organic contaminants in sewage sludge from the United States and China. Sci Total Environ. 2022;821:153423. 25. [https://www.epa.gov/biosolids/basic-information-about-biosolids]. 26. Biosolids. Global Strategic Business Report [https:// www.researchandmarkets.com/reports/5139451/ biosolids-global-strategic-business-report#rela0-5327510]. 27. Gavrilescu M, Demnerová K, Aamand J, Agathos S, Fava F. Emerging pollut- ants in the environment: present and future challenges in biomonitoring, ecological risks and bioremediation. New Biotechnol. 2015;32(1):147–56. 28. Petrie B, Barden R, Kasprzyk-Hordern B. A review on emerging contaminants in wastewaters and the environment: current knowledge, understudied areas and recommendations for future monitoring. Water Res. 2015;72:3–27. 29. Vasilachi IC, Asiminicesei DM, Fertu DI, Gavrilescu M. Occurrence and fate of emerging pollutants in Water Environment and Options for their removal. In: Water vol. 13; 2021. 30. United Nations Environment Programme. : An Assessment Report on Issues of Concern: Chemicals and Waste Issues Posing Risks to Human Health and the Environment. In.; 2020. 31. Richardson SD, Ternes TA. Water Analysis: emerging contaminants and cur- rent issues. Anal Chem. 2018;90(1):398–428. 32. Clarke RM, Cummins E. Evaluation of “Classic” and emerging contaminants resulting from the application of Biosolids to Agricultural Lands: a review. Hum Ecol Risk Assessment: Int J. 2015;21(2):492–513. 33. Lenka SP, Kah M, Padhye LP. A review of the occurrence, transformation, and removal of poly- and perfluoroalkyl substances (PFAS) in wastewater treat- ment plants. Water Res. 2021;199:117187. 34. Lindstrom AB, Strynar MJ, Delinsky AD, Nakayama SF, McMillan L, Libelo EL, Neill M, Thomas L. Application of WWTP Biosolids and resulting perfluo- rinated compound contamination of Surface and Well Water in Decatur, Alabama, USA. Environ Sci Technol. 2011;45(19):8015–21. 35. Lee H, Tevlin AG, Mabury SA, Mabury SA. Fate of polyfluoroalkyl phosphate diesters and their metabolites in Biosolids-Applied Soil: Biodegradation and Plant Uptake in Greenhouse and Field experiments. Environ Sci Technol. 2014;48(1):340–9. 36. Schowanek D, Carr R, David H, Douben P, Hall J, Kirchmann H, Patria L, Sequi P, Smith S, Webb S. A risk-based methodology for deriving quality standards for organic contaminants in sewage sludge for use in agriculture—conceptual Framework. Regul Toxicol Pharmacol. 2004;40(3):227–51. 37. Prosser RS, Sibley PK. Human health risk assessment of pharmaceuticals and personal care products in plant tissue due to biosolids and manure amend- ments, and wastewater irrigation. Environ Int. 2015;75:223–33. 38. What are Microplastics?. [https://oceanservice.noaa.gov/facts/microplastics. html]. 39. Murphy F, Ewins C, Carbonnier F, Quinn B. Wastewater Treatment Works (WwTW) as a source of Microplastics in the aquatic environment. Environ Sci Technol. 2016;50(11):5800–8. 40. Liu X, Yuan W, Di M, Li Z, Wang J. Transfer and fate of microplastics during the conventional activated sludge process in one wastewater treatment plant of China. Chem Eng J. 2019;362:176–82. 41. Hidayaturrahman H, Lee T-G. A study on characteristics of microplastic in wastewater of South Korea: identification, quantification, and fate of micro- plastics during treatment process. Mar Pollut Bull. 2019;146:696–702. 42. Allen S, Allen D, Phoenix VR, Le Roux G, Durántez Jiménez P, Simonneau A, Binet S, Galop D. Atmospheric transport and deposition of microplastics in a remote mountain catchment. Nat Geosci. 2019;12(5):339–44. 43. Brahney J, Hallerud M, Heim E, Hahnenberger M, Sukumaran S. Plastic rain in protected areas of the United States. Science. 2020;368(6496):1257–60. 44. Evangeliou N, Grythe H, Klimont Z, Heyes C, Eckhardt S, Lopez-Aparicio S, Stohl A. Atmospheric transport is a major pathway of microplastics to remote regions. Nat Commun. 2020;11(1):3381. 45. Feng S, Lu H, Tian P, Xue Y, Lu J, Tang M, Feng W. Analysis of microplastics in a remote region of the Tibetan Plateau: implications for natural environmental response to human activities. Sci Total Environ. 2020;739:140087. 46. Peeken I, Primpke S, Beyer B, Gütermann J, Katlein C, Krumpen T, Bergmann M, Hehemann L, Gerdts G. Arctic sea ice is an important temporal sink and means of transport for microplastic. Nat Commun. 2018;9(1):1505. 47. Prata JC, da Costa JP, Lopes I, Duarte AC, Rocha-Santos T. Environmental exposure to microplastics: an overview on possible human health effects. Sci Total Environ. 2020;702:134455. 48. Prata JC. Airborne microplastics: consequences to human health? Environ Pollut. 2018;234:115–26. 49. Dehghani S, Moore F, Akhbarizadeh R. Microplastic pollution in deposited urban dust, Tehran metropolis, Iran. Environ Sci Pollut Res. 2017;24(25):20360–71. 50. Gasperi J, Wright SL, Dris R, Collard F, Mandin C, Guerrouache M, Langlois V, Kelly FJ, Tassin B. Microplastics in air: are we breathing it in? Curr Opin Environ Sci Health. 2018;1:1–5. 51. Mbachu O, Jenkins G, Pratt C, Kaparaju P. A New Contaminant Superhighway? A review of sources, measurement techniques and Fate of Atmospheric Microplastics. Water Air Soil Pollut. 2020;231(2):85. 52. Pramanik BK, Roychand R, Monira S, Bhuiyan M, Jegatheesan V. Fate of road- dust associated microplastics and per- and polyfluorinated substances in stormwater. Process Saf Environ Prot. 2020;144:236–41. 53. Abbasi S, Keshavarzi B, Moore F, Turner A, Kelly FJ, Dominguez AO, Jaafar- zadeh N. Distribution and potential health impacts of microplastics and microrubbers in air and street dusts from Asaluyeh County, Iran. Environ Pollut. 2019;244:153–64. 54. Järlskog I, Strömvall A-M, Magnusson K, Gustafsson M, Polukarova M, Galfi H, Aronsson M, Andersson-Sköld Y. Occurrence of tire and bitumen wear micro- plastics on urban streets and in sweepsand and washwater. Sci Total Environ. 2020;729:138950. 55. Liu K, Wang X, Song Z, Wei N, Li D. Terrestrial plants as a potential tempo- rary sink of atmospheric microplastics during transport. Sci Total Environ. 2020;742:140523. 56. Rillig MC. Microplastic in Terrestrial Ecosystems and the Soil? Environ Sci Technol. 2012;46(12):6453–4. 57. Calderón-Preciado D, Matamoros V, Bayona JM. Occurrence and potential crop uptake of emerging contaminants and related compounds in an agri- cultural irrigation network. Sci Total Environ. 2011;412–413:14–9. 58. Krause S, Molari M, Gorb EV, Gorb SN, Kossel E, Haeckel M. Persistence of plas- tic debris and its colonization by bacterial communities after two decades on the abyssal seafloor. Sci Rep. 2020;10(1):9484. 59. Buck RC, Franklin J, Berger U, Conder JM, Cousins IT, de Voogt P, Jensen AA, Kannan K, Mabury SA, van Leeuwen SPJ. Perfluoroalkyl and polyfluoroalkyl substances in the environment: terminology, classification, and origins. Integr Environ Assess Manag. 2011;7(4):513–41. 60. Dean WS, Adejumo HA, Caiati A, Garay PM, Harmata AS, Li L, Rodriguez EE, Sundar S. A Framework for Regulation of New and existing PFAS by EPA. J Sci Policy Gov. 2020;16(1):1–14. 61. Chow SJ, Ojeda N, Jacangelo JG, Schwab KJ. Detection of ultrashort-chain and other per- and polyfluoroalkyl substances (PFAS) in U.S. bottled water. Water Res. 2021;201:117292. 62. Cousins IT, Vestergren R, Wang Z, Scheringer M, McLachlan MS. The precau- tionary principle and chemicals management: the example of perfluoroalkyl acids in groundwater. Environ Int. 2016;94:331–40. 63. Kotlarz N, McCord J, Collier D, Lea CS, Strynar M, Lindstrom AB, Wilkie AA, Islam JY, Matney K, Tarte P, et al. Measurement of Novel, drinking Water-Asso- ciated PFAS in blood from adults and children in Wilmington, North Carolina. Environ Health Perspect. 2020;128(7):077005. 64. Scheringer M, Trier X, Cousins IT, de Voogt P, Fletcher T, Wang Z, Webster TF. Helsingør Statement on poly- and perfluorinated alkyl substances (PFASs). Chemosphere. 2014;114:337–9. 65. Glüge J, Scheringer M, Cousins IT, DeWitt JC, Goldenman G, Herzke D, Lohmann R, Ng CA, Trier X, Wang Z. An overview of the uses of per- and polyfluoroalkyl substances (PFAS). Environ Science: Processes Impacts. 2020;22(12):2345–73. 66. Armstrong DL, Lozano N, Rice CP, Ramirez M, Torrents A. Temporal trends of perfluoroalkyl substances in limed biosolids from a large municipal water resource recovery facility. J Environ Manage. 2016;165:88–95. 67. Miner KR, Clifford H, Taruscio T, Potocki M, Solomon G, Ritari M, Napper IE, Gajurel AP, Mayewski PA. Deposition of PFAS ‘forever chemicals’ on Mt. Ever- est. Sci Total Environ. 2021;759:144421. 68. Prevedouros K, Cousins IT, Buck RC, Korzeniowski SH. Sources, fate and trans- port of Perfluorocarboxylates. Environ Sci Technol. 2006;40(1):32–44. Page 13 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 69. Butt CM, Berger U, Bossi R, Tomy GT. Levels and trends of poly- and perfluorinated compounds in the arctic environment. Sci Total Environ. 2010;408(15):2936–65. 70. Young AS, Sparer-Fine EH, Pickard HM, Sunderland EM, Peaslee GF, Allen JG. Per- and polyfluoroalkyl substances (PFAS) and total fluorine in fire station dust. J Expo Sci Environ Epidemiol. 2021;31(5):930–42. 71. Nicole W. Breaking it down: estimating short-chain PFAS half-lives in a Human Population. Environ Health Perspect. 2020;128(11):114002. 72. Sáez M, de Voogt P, Parsons JR. Persistence of perfluoroalkylated substances in closed bottle tests with municipal sewage sludge. Environ Sci Pollut Res. 2008;15(6):472–7. 73. Zareitalabad P, Siemens J, Hamer M, Amelung W. Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in surface waters, sediments, soils and wastewater – a review on concentrations and distribution coef- ficients. Chemosphere. 2013;91(6):725–32. 74. Shin H-M, Vieira VM, Ryan PB, Detwiler R, Sanders B, Steenland K, Bartell SM. Environmental fate and transport modeling for Perfluorooctanoic Acid emit- ted from the Washington Works Facility in West Virginia. Environ Sci Technol. 2011;45(4):1435–42. 75. De Silva AO, Armitage JM, Bruton TA, Dassuncao C, Heiger-Bernays W, Hu XC, Kärrman A, Kelly B, Ng C, Robuck A, et al. PFAS exposure pathways for humans and Wildlife: a synthesis of current knowledge and key gaps in understanding. Environ Toxicol Chem. 2021;40(3):631–57. 76. Kennedy GL, Butenhoff JL, Olsen GW, O’Connor JC, Seacat AM, Perkins RG, Biegel LB, Murphy SR, Farrar DG. The Toxicology of Perfluorooctanoate. Crit Rev Toxicol. 2004;34(4):351–84. 77. Sunderland EM, Hu XC, Dassuncao C, Tokranov AK, Wagner CC, Allen JG. A review of the pathways of human exposure to poly- and perfluoroalkyl substances (PFASs) and present understanding of health effects. J Expo Sci Environ Epidemiol. 2019;29(2):131–47. 78. Trudel D, Horowitz L, Wormuth M, Scheringer M, Cousins IT, Hunger- bühler K. Estimating consumer exposure to PFOS and PFOA. Risk Anal. 2008;28(2):251–69. 79. Conder JM, Hoke RA, Wolf Wd, Russell MH, Buck RC. Are PFCAs Bioaccumula- tive? A critical review and comparison with Regulatory Criteria and Persistent Lipophilic Compounds. Environ Sci Technol. 2008;42(4):995–1003. 80. Martin JW, Whittle DM, Muir DCG, Mabury SA. Perfluoroalkyl Contaminants in a Food web from Lake Ontario. Environ Sci Technol. 2004;38(20):5379–85. 81. Pérez F, Nadal M, Navarro-Ortega A, Fàbrega F, Domingo JL, Barceló D, Farré M. Accumulation of perfluoroalkyl substances in human tissues. Environ Int. 2013;59:354–62. 82. Agency for Toxic Substances and Disease Registry (US). Toxicological Profile for Perfluoroalkyls. Atlanta, GA: Agency for Toxic Substances and Disease Registry (US); 2021. 83. Sørli JB, Låg M, Ekeren L, Perez-Gil J, Haug LS, Da Silva E, Matrod MN, Gützkow KB, Lindeman B. Per- and polyfluoroalkyl substances (PFASs) modify lung surfactant function and pro-inflammatory responses in human bronchial epithelial cells. Toxicol In Vitro. 2020;62:104656. 84. Product. – Chemical Profile for Treatments Containing Perfluoroalkyl or Poly- fluoroalkyl Substances for Use on Converted Textiles or Leathers. In. Edited by Control DoTS; 2021. 85. Calafat AM, Kuklenyik Z, Reidy JA, Caudill SP, Tully JS, Needham LL. Serum concentrations of 11 Polyfluoroalkyl Compounds in the U.S. Population: data from the National Health and Nutrition Examination Survey (NHANES) 1999 – 2000. Environ Sci Technol. 2007;41(7):2237–42. 86. Toxicological Effects of Perfluoroalkyl and Polyfluoroalkyl Substances., 1 edn: Humana Cham; 2015. 87. Borthakur A, Wang M, He M, Ascencio K, Blotevogel J, Adamson DT, Mahen- dra S, Mohanty SK. Perfluoroalkyl acids on suspended particles: significant transport pathways in surface runoff, surface waters, and subsurface soils. J Hazard Mater. 2021;417:126159. 88. Wang Y, Huang H. Chap. 8 - Carbon nanotube composite membranes for microfiltration of pharmaceuticals and personal care products. In: Advanced Nanomaterials for Membrane Synthesis and its Applications Edited by Lau W-J, Ismail AF, Isloor A, Al-Ahmed A: Elsevier; 2019: 183–202. 89. Bishnoi MM, Verma A, Kushwaha A, Goswami S. Chap. 9 - Social factors influencing household waste management. In: Emerging Trends to Approach- ing Zero Waste Edited by Hussain CM, Singh S, Goswami L: Elsevier; 2022: 197–213. 90. Bayabil HK, Teshome FT, Li YC. Emerging contaminants in Soil and Water. Front Environ Sci 2022, 10. 91. Cooper ER, Siewicki TC, Phillips K. Preliminary risk assessment database and risk ranking of pharmaceuticals in the environment. Sci Total Environ. 2008;398(1):26–33. 92. Wang J, Wang S. Removal of pharmaceuticals and personal care products (PPCPs) from wastewater: a review. J Environ Manage. 2016;182:620–40. 93. Clarke BO, Smith SR. Review of ‘emerging’ organic contaminants in biosolids and assessment of international research priorities for the agricultural use of biosolids. Environ Int. 2011;37(1):226–47. 94. Körner W, Bolz U, Süßmuth W, Hiller G, Schuller W, Hanf V, Hagenmaier H. Input/output balance of estrogenic active compounds in a major municipal sewage plant in Germany. Chemosphere. 2000;40(9):1131–42. 95. Langdon KA, Warne MSJ, Smernik RJ, Shareef A, Kookana RS. Selected per- sonal care products and endocrine disruptors in biosolids: an Australia-wide survey. Sci Total Environ. 2011;409(6):1075–81. 96. Chen J, Pycke BFG, Brownawell BJ, Kinney CA, Furlong ET, Kolpin DW, Halden RU. Occurrence, temporal variation, and estrogenic burden of five parabens in sewage sludge collected across the United States. Sci Total Environ. 2017;593–594:368–74. 97. United States Environmental Protection Agency. : Targeted National Sewage Sludge Survey Sampling and Analysis Technical Report. In. Edited by Water Oo; 2009. 98. Guo J, Li J, Chen H, Bond PL, Yuan Z. Metagenomic analysis reveals wastewa- ter treatment plants as hotspots of antibiotic resistance genes and mobile genetic elements. Water Res. 2017;123:468–78. 99. Jelic A, Fatone F, Di Fabio S, Petrovic M, Cecchi F, Barcelo D. Tracing pharma- ceuticals in a municipal plant for integrated wastewater and organic solid waste treatment. Sci Total Environ. 2012;433:352–61. 100. Morais SA, Delerue-Matos C, Gabarrell X, Blánquez P. Multimedia fate model- ing and comparative impact on freshwater ecosystems of pharmaceuticals from biosolids-amended soils. Chemosphere. 2013;93(2):252–62. 101. Rivera-Utrilla J, Sánchez-Polo M, Ferro-García M, Prados-Joya G, Ocampo- Pérez R. Pharmaceuticals as emerging contaminants and their removal from water. A review. Chemosphere. 2013;93(7):1268–87. 102. Buta M, Hubeny J, Zieliński W, Harnisz M, Korzeniewska E. Sewage sludge in agriculture – the effects of selected chemical pollutants and emerging genetic resistance determinants on the quality of soil and crops – a review. Ecotoxicol Environ Saf. 2021;214:112070. 103. De Coster S, van Larebeke N. Endocrine-disrupting chemicals: Associated Dis- orders and Mechanisms of Action. J Environ Public Health. 2012;2012:713696. 104. Nash Jon P, Kime David E, Van der Ven Leo TM, Wester Piet W, Brion F, Maack G, Stahlschmidt-Allner P, Tyler Charles R. Long-term exposure to environmen- tal concentrations of the Pharmaceutical Ethynylestradiol causes Reproduc- tive failure in Fish. Environ Health Perspect. 2004;112(17):1725–33. 105. Kidd KA, Blanchfield PJ, Mills KH, Palace VP, Evans RE, Lazorchak JM, Flick RW. Collapse of a fish population after exposure to a synthetic estrogen. Proceed- ings of the National Academy of Sciences 2007, 104(21):8897–8901. 106. Barber LB, Vajda AM, Douville C, Norris DO, Writer JH. Fish Endocrine disrup- tion responses to a major Wastewater Treatment Facility Upgrade. Environ Sci Technol. 2012;46(4):2121–31. 107. Vajda AM, Barber LB, Gray JL, Lopez EM, Bolden AM, Schoenfuss HL, Norris DO. Demasculinization of male fish by wastewater treatment plant effluent. Aquat Toxicol. 2011;103(3):213–21. 108. OECD. : Pharmaceutical Residues in Freshwater; 2019. 109. Miraji H, Othman OC, Ngassapa FN, Mureithi EW. Research Trends in Emerg- ing Contaminants on the Aquatic Environments of Tanzania. Scientifica 2016, 2016:3769690. 110. Mortensen A, Granby K, Eriksen FD, Cederberg TL, Friis-Wandall S, Simonsen Y, Broesbøl-Jensen B, Bonnichsen R. Levels and risk assessment of chemical contaminants in byproducts for animal feed in Denmark. J Environ Sci Health Part B. 2014;49(11):797–810. 111. Cycoń M, Mrozik A, Piotrowska-Seget Z. Antibiotics in the Soil Environment— Degradation and their impact on Microbial Activity and Diversity. Front Microbiol 2019, 10. 112. Kraemer SA, Ramachandran A, Perron GG. Antibiotic Pollution in the Environ- ment: from Microbial Ecology to Public Policy. In: Microorganisms vol. 7; 2019. 113. Ross J, Topp E. Abundance of Antibiotic Resistance genes in bacterio- phage following Soil fertilization with dairy manure or municipal bio- solids, and evidence for potential transduction. Appl Environ Microbiol. 2015;81(22):7905–13. 114. Yang L, Liu W, Zhu D, Hou J, Ma T, Wu L, Zhu Y, Christie P. Application of biosolids drives the diversity of antibiotic resistance genes in soil and lettuce at harvest. Soil Biol Biochem. 2018;122:131–40. Page 14 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 115. Murray R, Tien Y-C, Scott A, Topp E. The impact of municipal sewage sludge stabilization processes on the abundance, field persistence, and transmission of antibiotic resistant bacteria and antibiotic resistance genes to vegetables at harvest. Sci Total Environ. 2019;651:1680–7. 116. Wolters B, Hauschild K, Blau K, Mulder I, Heyde BJ, Sørensen SJ, Siemens J, Jechalke S, Smalla K, Nesme J. Biosolids for safe land application: does waste- water treatment plant size matters when considering antibiotics, pollutants, microbiome, mobile genetic elements and associated resistance genes? Environ Microbiol. 2022;24(3):1573–89. 117. Reid BJ, Jones KC, Semple KT. Bioavailability of persistent organic pollutants in soils and sediments—a perspective on mechanisms, consequences and assessment. Environ Pollut. 2000;108(1):103–12. 118. Borthakur A, Cranmer BK, Dooley GP, Blotevogel J, Mahendra S, Mohanty SK. Release of soil colloids during flow interruption increases the pore-water PFAS concentration in saturated soil. Environ Pollut. 2021;286:117297. 119. Borthakur A, Olsen P, Dooley GP, Cranmer BK, Rao U, Hoek EMV, Blotevogel J, Mahendra S, Mohanty SK. Dry-wet and freeze-thaw cycles enhance PFOA leaching from subsurface soils. J Hazard Mater Lett. 2021;2:100029. 120. Tran NH, Reinhard M, Gin KY-H. Occurrence and fate of emerging contami- nants in municipal wastewater treatment plants from different geographical regions-a review. Water Res. 2018;133:182–207. 121. Chen W, Xu J, Lu S, Jiao W, Wu L, Chang AC. Fates and transport of PPCPs in soil receiving reclaimed water irrigation. Chemosphere. 2013;93(10):2621–30. 122. Al-Rajab AJ, Sabourin L, Lapen DR, Topp E. Dissipation of triclosan, triclocar- ban, carbamazepine and naproxen in agricultural soil following surface or sub-surface application of dewatered municipal biosolids. Sci Total Environ. 2015;512–513:480–8. 123. Cantarero R, Richter P, Brown S, Ascar L, Ahumada I. Effects of applying biosol- ids to soils on the adsorption and bioavailability of 17α-ethinylestradiol and triclosan in wheat plants. Environ Sci Pollut Res. 2017;24(14):12847–59. 124. Yager TJB, Furlong ET, Kolpin DW, Kinney CA, Zaugg SD, Burkhardt MR. Dis- sipation of contaminants of emerging concern in Biosolids Applied to Nonir- rigated Farmland in Eastern Colorado. JAWRA J Am Water Resour Association. 2014;50(2):343–57. 125. Wang K, Larkin T, Singhal N, Song Y. Mobility of pharmaceutical and personal care products in lime amended wastewater biosolids. Sci Total Environ. 2018;624:1263–73. 126. Yang Y-Y, Gray JL, Furlong ET, Davis JG, ReVello RC, Borch T. Steroid hormone runoff from Agricultural Test Plots Applied with Municipal Biosolids. Environ Sci Technol. 2012;46(5):2746–54. 127. Gray JL, Borch T, Furlong ET, Davis JG, Yager TJ, Yang Y-Y, Kolpin DW. Rainfall- runoff of anthropogenic waste indicators from agricultural fields applied with municipal biosolids. Sci Total Environ. 2017;580:83–9. 128. Gottschall N, Topp E, Metcalfe C, Edwards M, Payne M, Kleywegt S, Russell P, Lapen DR. Pharmaceutical and personal care products in groundwater, sub- surface drainage, soil, and wheat grain, following a high single application of municipal biosolids to a field. Chemosphere. 2012;87(2):194–203. 129. Shipkova M, Armstrong VW, Oellerich M, Wieland E. Acyl Glucuronide Drug Metabolites: Toxicological and Analytical Implications. Ther Drug Monit 2003, 25(1). 130. Walgren JL, Mitchell MD, Thompson DC. Role of metabolism in Drug-Induced Idiosyncratic Hepatotoxicity. Crit Rev Toxicol. 2005;35(4):325–61. 131. Macherius A, Eggen T, Lorenz W, Moeder M, Ondruschka J, Reemtsma T. Metabolization of the Bacteriostatic Agent Triclosan in Edible plants and its consequences for Plant Uptake Assessment. Environ Sci Technol. 2012;46(19):10797–804. 132. Ben Mordechay E, Tarchitzky J, Chen Y, Shenker M, Chefetz B. Composted biosolids and treated wastewater as sources of pharmaceuticals and personal care products for plant uptake: a case study with carbamazepine. Environ Pollut. 2018;232:164–72. 133. Kinney CA, Heuvel BV. Translocation of pharmaceuticals and personal care products after land application of biosolids. Curr Opin Environ Sci Health. 2020;14:23–30. 134. Kinney CA, Campbell BR, Thompson R, Furlong ET, Kolpin DW, Burkhardt MR, Zaugg SD, Werner SL, Hay AG. Earthworm bioassays and seedling emergence for monitoring toxicity, aging and bioaccumulation of anthropogenic waste indicator compounds in biosolids–amended soil. Sci Total Environ. 2012;433:507–15. 135. Dsikowitzky L, Crawford SE, Nordhaus I, Lindner F, Dwiyitno, Irianto HE, Ariyani F, Schwarzbauer J. Analysis and environmental risk assessment of priority and emerging organic pollutants in sediments from the tropical coastal megacity Jakarta, Indonesia. Reg Stud Mar Sci. 2020;34:101021. 136. Al Aukidy M, Verlicchi P, Jelic A, Petrovic M, Barcelò D. Monitoring release of pharmaceutical compounds: occurrence and environmental risk assessment of two WWTP effluents and their receiving bodies in the Po Valley, Italy. Sci Total Environ. 2012;438:15–25. 137. Stuart M, Lapworth D, Crane E, Hart A. Review of risk from potential emerging contaminants in UK groundwater. Sci Total Environ. 2012;416:1–21. 138. Engwall M, Hjelm K. Uptake of dioxin-like compounds from sewage sludge into various plant species–assessment of levels using a sensitive bioassay. Chemosphere. 2000;40(9–11):1189–95. 139. Wu C, Spongberg AL, Witter JD, Fang M, Czajkowski KP. Uptake of Pharma- ceutical and Personal Care products by soybean plants from Soils Applied with Biosolids and Irrigated with Contaminated Water. Environ Sci Technol. 2010;44(16):6157–61. 140. Wu C, Spongberg AL, Witter JD, Sridhar BBM. Transfer of wastewater associ- ated pharmaceuticals and personal care products to crop plants from biosolids treated soil. Ecotoxicol Environ Saf. 2012;85:104–9. 141. Wu X, Dodgen LK, Conkle JL, Gan J. Plant uptake of pharmaceutical and personal care products from recycled water and biosolids: a review. Sci Total Environ. 2015;536:655–66. 142. Gaylor MO, Harvey E, Hale RC. Polybrominated Diphenyl Ether (PBDE) Accu- mulation by earthworms (Eisenia fetida) exposed to Biosolids-, polyurethane foam Microparticle-, and Penta-BDE-Amended Soils. Environ Sci Technol. 2013;47(23):13831–9. 143. Rivier P-A, Havranek I, Coutris C, Norli HR, Joner EJ. Transfer of organic pollut- ants from sewage sludge to earthworms and barley under field conditions. Chemosphere. 2019;222:954–60. 144. Geissen V, Mol H, Klumpp E, Umlauf G, Nadal M, van der Ploeg M, van de Zee SEATM, Ritsema CJ. Emerging pollutants in the environment: a challenge for water resource management. Int Soil Water Conserv Res. 2015;3(1):57–65. 145. Tang Y, Yin M, Yang W, Li H, Zhong Y, Mo L, Liang Y, Ma X, Sun X. Emerging pollutants in water environment: occurrence, monitoring, fate, and risk assessment. Water Environ Res. 2019;91(10):984–91. 146. Naidu R, Arias Espana VA, Liu Y, Jit J. Emerging contaminants in the environment: risk-based analysis for better management. Chemosphere. 2016;154:350–7. 147. Horton AA, Walton A, Spurgeon DJ, Lahive E, Svendsen C. Microplastics in freshwater and terrestrial environments: evaluating the current understand- ing to identify the knowledge gaps and future research priorities. Sci Total Environ. 2017;586:127–41. 148. EPA EcoBox Tools by Exposure Pathways - Soil. [https://www.epa.gov/ ecobox/epa-ecobox-tools-exposure-pathways-soil]. 149. Bao L-J, Wei Y-L, Yao Y, Ruan Q-Q, Zeng EY. Global trends of research on emerging contaminants in the environment and humans: a literature assimi- lation. Environ Sci Pollut Res. 2015;22(3):1635–43. 150. Hernández F, Sancho JV, Ibáñez M, Guerrero C. Antibiotic residue deter- mination in environmental waters by LC-MS. TRAC Trends Anal Chem. 2007;26(6):466–85. 151. Boyd GR, Reemtsma H, Grimm DA, Mitra S. Pharmaceuticals and personal care products (PPCPs) in surface and treated waters of Louisiana, USA and Ontario, Canada. Sci Total Environ. 2003;311(1):135–49. 152. Petrović M, Hernando MD, Díaz-Cruz MS, Barceló D. Liquid chromatography– tandem mass spectrometry for the analysis of pharmaceutical residues in environmental samples: a review. J Chromatogr A. 2005;1067(1):1–14. 153. Richardson BJ, Lam PKS, Martin M. Emerging chemicals of concern: pharma- ceuticals and personal care products (PPCPs) in Asia, with particular reference to Southern China. Mar Pollut Bull. 2005;50(9):913–20. 154. Gray AD, Weinstein JE. Size- and shape-dependent effects of microplastic particles on adult daggerblade grass shrimp (Palaemonetes pugio). Environ Toxicol Chem. 2017;36(11):3074–80. 155. Hwang J, Choi D, Han S, Jung SY, Choi J, Hong J. Potential toxicity of polysty- rene microplastic particles. Sci Rep. 2020;10(1):7391. 156. Xing Y-F, Xu Y-H, Shi M-H, Lian Y-X. The impact of PM2.5 on the human respi- ratory system. J Thorac Disease. 2016;8(1):E69–E74. 157. Houtz EF, Sedlak DL. Oxidative Conversion as a Means of detecting precursors to perfluoroalkyl acids in Urban Runoff. Environ Sci Technol. 2012;46(17):9342–9. 158. United States Environmental Protection Agency Press Office. : EPA Announces First Validated Laboratory Method to Test for PFAS in Wastewater, Surface Water, Groundwater, Soils. In.; 2021. 159. Berg C, Crone B, Gullett B, Higuchi M, Krause MJ, Lemieux PM, Martin T, Shields EP, Struble E, Thoma E, et al. Developing innovative treatment Page 15 of 15Pozzebon and Seifert Environmental Health (2023) 22:57 technologies for PFAS-containing wastes. J Air Waste Manag Assoc. 2022;72(6):540–55. 160. Winchell LJ, Ross JJ, Brose DA, Pluth TB, Fonoll X, Norton JW Jr, Bell KY. Pyroly- sis and gasification at water resource recovery facilities: Status of the industry. Water Environ Res. 2022;94(3):e10701. 161. Chen W-T, Haque MA, Lu T, Aierzhati A, Reimonn G. A perspective on hydrothermal processing of sewage sludge. Curr Opin Environ Sci Health. 2020;14:63–73. 162. Chen W-T, Zhang Y, Lee TH, Wu Z, Si B, Lee C-FF, Lin A, Sharma BK. Renewable diesel blendstocks produced by hydrothermal liquefaction of wet biowaste. Nat Sustain. 2018;1(11):702–10. 163. Trang B, Li Y, Xue X-S, Ateia M, Houk KN, Dichtel WR. Low-temperature miner- alization of perfluorocarboxylic acids. Science. 2022;377(6608):839–45. 164. Liu Y, Ptacek CJ, Beauchemin S, MacKinnon T, Blowes DW. Effect of compost- ing and amendment with biochar and woodchips on the fate and leach- ability of pharmaceuticals in biosolids destined for land application. Sci Total Environ. 2022;810:151193. 165. Kim Lazcano R, de Perre C, Mashtare ML, Lee LS. Per- and polyfluoroalkyl substances in commercially available biosolid-based products: the effect of treatment processes. Water Environ Res. 2019;91(12):1669–77. 166. Huber S, Moe MK, Schmidbauer JN, Hansen G, Herzke D. Emission from Incineration of Fluoropolymer materials: A literature survey. In: 2009; 2009. 167. Henry BJ, Carlin JP, Hammerschmidt JA, Buck RC, Buxton LW, Fiedler H, Seed J, Hernandez O. A critical review of the application of polymer of low concern and regulatory criteria to fluoropolymers. Integr Environ Assess Manag. 2018;14(3):316–34. 168. Aleksandrov K, Gehrmann H-J, Hauser M, Mätzing H, Pigeon D, Stapf D, Wexler M. Waste incineration of polytetrafluoroethylene (PTFE) to evaluate potential formation of per- and poly-fluorinated alkyl substances (PFAS) in flue gas. Chemosphere. 2019;226:898–906. 169. Feng M, Qu R, Wei Z, Wang L, Sun P, Wang Z. Characterization of the ther- molysis products of Nafion membrane: a potential source of perfluorinated compounds in the environment. Sci Rep. 2015;5(1):9859. 170. Schlummer M, Sölch C, Meisel T, Still M, Gruber L, Wolz G. Emission of perfluo- roalkyl carboxylic acids (PFCA) from heated surfaces made of polytetrafluo- roethylene (PTFE) applied in food contact materials and consumer products. Chemosphere. 2015;129:46–53. 171. Venkatesan AK, Done HY, Halden RU. United States National Sewage Sludge Repository at Arizona State University—a new resource and research tool for environmental scientists, engineers, and epidemiologists. Environ Sci Pollut Res. 2015;22(3):1577–86. 172. Kim Lazcano R, Choi YJ, Mashtare ML, Lee LS. Characterizing and com- paring per- and polyfluoroalkyl substances in commercially available Biosolid and Organic Non-Biosolid-Based Products. Environ Sci Technol. 2020;54(14):8640–8. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. 94 From:Anderson, Matt Sent:Wednesday, August 14, 2024 10:14 AM To:Jayna K (jaynak@fglinc.com) Subject:September One Off Sampling COC and Bottle Request Attachments:Order R3-2024-0001 (1).pdf Good morning Jayna, I will try to catch up with you via phone soon. In the meantime, I would like to request the COC for the September monthly, with bottles and labels (please). I need to talk to the lab team, but the ideal sample date would be 9/3. Thanks, Matt Sample ID Sample Type Analytes Eff-001 C WW Composite Chlorodibromomethane (aka Dibromochloromethane), Chloroform, Dichlorobromomethane, Methylene Chloride, Pentachlorophenol, Methylene Blue Active Substances (MBAS) Eff-001 G WW Grab Oil and Grease, Total Kjeldahl Nitrogen (TKN) (as N), Nitrate (as N), Nitrite (as N), Molybdenum, Dissolved Orthophosphate (as P), Total Phosphate (as P), Total Dissolved Solids (TDS), Sodium, Chloride, Sulfate RSW-004 Surface Water Grab Un-ionized Ammonia (as N), Nitrate (as N), Total Phosphate (as P), Ammonia, Total (as N), Total Kjeldahl Nitrogen (as N), Chloride, Sulfate RSW-005 Surface Water Grab Un-ionized Ammonia as N, Nitrate (as N), Total Phosphate (as P), Ammonia, Total (as N), Total Kjeldahl Nitrogen (as N), Total Dissolved Solids (TDS), Chloride, Sulfate RSW-007 Surface Water Grab Nitrate (as N), Total Phosphate (as P), Ammonia, Total (as N), Total Kjeldahl Nitrogen (as N), Total Dissolved Solids (TDS), Chloride, Sulfate RSW-008 Surface Water Grab Nitrate (as N), Total Phosphate (as P), Ammonia, Total (as N), Total Kjeldahl Nitrogen (as N), Total 95 Dissolved Solids (TDS), Chloride, Sulfate Matt Anderson Laboratory Manager Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications 96 From:Anderson, Matt Sent:Thursday, August 8, 2024 12:48 PM To:Barbara Orelo; Lee, Tyler Subject:RE: [External] - Intro Email Attachments:Order R3-2024-0001.pdf Barbara, Quick introduction: I have added our Chief Operator, Tyler Lee, to this response. Tyler and I will be working on the TRE work plan and will be in contact soon. On page 18, section 6.3.2.1.1, the TRE work plan is due within 90 days of the effective date of the order, which pushes us out to December.- Matt From: Barbara Orelo <barbara.orelo@enthalpy.com> Sent: Tuesday, August 6, 2024 3:01 PM To: Anderson, Matt <manderso@slocity.org> Subject: Re: [External] - Intro Email Hi Matt, Thanks for your time on the call today! Here is a summary of what we discussed: We will be increasing the test replicates for the chronic Ceriodaphnia test only. The fathead minnow and green algae will be tested with standard replication. We will move the start of the chronic and acute species sensitivity screening to November, to avoid screening with the Eff-001B sample, that needs to be tested in October. Samples should be collected on Monday, Wednesday, and Thursday after 8am. Samples should be shipped in a cooler with ice via FedEx priority overnight. For the monthly fathead minnow test, please collect 4L per sample. For the species sensitivity screening, please collect 8L per sample. Attached is a copy of our COC. I pre-filled the analyses required. There is a tab for fathead minnow and a tab for species sensitivity screening with acute. Please fill out the "report to" and "Invoice" sections as well as the sample information. Include a copy of the relinquished COC in the cooler in a plastic bag. I will send you sample containers for the first 3 months of testing. Let me know how you want to move forward regarding the new TRE workplan. We can help you write a new one based on your new NPDES or update the old one. As a reminder, we have until the end of September to submit the new plan to the water board. Here is my proposed test schedule for 2024-2025. Let me know if you'd like to make any changes 2024 Week of September 9th - Chronic fathead minnow Week of October 7th - Chronic fathead minnow (Eff-001B) Week of November 4th - Acute and Chronic species sensitivity screening Week of December 2nd - Chronic fathead minnow 2025 Week of January 6th - Chronic species sensitivity screening Week of February 3rd - Chronic fathead minnow Week of March 3rd - Chronic fathead minnow 97 Week of April 7th - Chronic species sensitivity screening Week of May 5th - Chronic fathead minnow Week of June 2nd - Chronic fathead minnow Week of July 7th - Chronic species sensitivity screening Week of August 4th - Chronic - species depends on results of species sensitivity screening Week of September 8th - Chronic - species depends on results of species sensitivity screening Week of October 6th - Chronic - species depends on results of species sensitivity screening (Eff-001B) Week of November 3rd - Chronic and Acute - species depends on results of species sensitivity screening Week of December 1st - Chronic - species depends on results of species sensitivity screening Let me know if I missed anything. It was great to meet you! Barbara Orelo (she/her) Project Manager, Environmental Toxicology Enthalpy Analytical, LLC. 4340 Vandever Ave. 92120 San Diego, CA | US Pacific Time (858)587-7333 x 14008 From: Anderson, Matt <manderso@slocity.org> Sent: Tuesday, July 30, 2024 2:36 PM To: Barbara Orelo <barbara.orelo@enthalpy.com> Subject: RE: [External] - Intro Email Perfect, we’ll meet on teams next week. From: Barbara Orelo <barbara.orelo@enthalpy.com> Sent: Tuesday, July 30, 2024 2:34 PM To: Anderson, Matt <manderso@slocity.org> Subject: Re: [External] - Intro Email Hi Matt, Yes! All communication can be routed through me 덞덛덟덜덝 Barbara Orelo (she/her) Project Manager, Environmental Toxicology Enthalpy Analytical, LLC. 4340 Vandever Ave. 92120 San Diego, CA | US Pacific Time (858)587-7333 x 14008 From: Anderson, Matt <manderso@slocity.org> Sent: Tuesday, July 30, 2024 2:32 PM To: Barbara Orelo <barbara.orelo@enthalpy.com> Subject: RE: [External] - Intro Email Got it. Just to clarify, with you being our PM, can I route all communication through you? - Matt From: Barbara Orelo <barbara.orelo@enthalpy.com> Sent: Tuesday, July 30, 2024 2:28 PM 98 To: Anderson, Matt <manderso@slocity.org> Subject: Re: [External] - Intro Email Hi Matt, I scheduled a meeting at 2pm. Let me know if you got the invite. Looking forward to talking with you! Barbara Orelo (she/her) Project Manager, Environmental Toxicology Enthalpy Analytical, LLC. 4340 Vandever Ave. 92120 San Diego, CA | US Pacific Time (858)587-7333 x 14008 From: Anderson, Matt <manderso@slocity.org> Sent: Tuesday, July 30, 2024 2:04 PM To: Barbara Orelo <barbara.orelo@enthalpy.com> Subject: RE: [External] - Intro Email Barabara, Can we book the 2 pm on Tuesday? - Matt From: Barbara Orelo <barbara.orelo@enthalpy.com> Sent: Tuesday, July 30, 2024 12:30 PM To: Anderson, Matt <manderso@slocity.org> Cc: Katie Payne <katie.payne@enthalpy.com > Subject: Re: [External] - Intro Email This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Hi Matt, It's nice to meet you electronically and I look forward to working with you! I reviewed all of your testing requirements and have some questions that I want to discuss with you before we start testing. We can also go over logistics. Are you available next week? I am available on Tuesday any time after 2pm, Wednesday morning, Wednesday after 2pm, or anytime next Friday. Let me know and I will schedule a Teams Meeting. Thanks! Barbara Orelo (she/her) Project Manager, Environmental Toxicology Enthalpy Analytical, LLC. 4340 Vandever Ave. 92120 San Diego, CA | US Pacific Time (858)587-7333 x 14008 You don't often get email from manderso@slocity.org. Learn why this is important 99 From: Anderson, Matt <manderso@slocity.org> Sent: Tuesday, July 30, 2024 11:00 AM To: Barbara Orelo <barbara.orelo@enthalpy.com> Cc: Katie Payne <katie.payne@enthalpy.com > Subject: [External] - Intro Email Good morning Barbara, I hope all is well this Tuesday morning. We are excited to begin working with you. Can we start to schedule the shipment of containers and chains of custody for the September sample event? Can we schedule a meeting in later August or early September to plan the schedule and containers for October? October will be challenging with both Eff- 001 A and B, annual acute, acute sensitivity screening, and beginning of the chronic sensitivity screening. As for carriers, do you have a preference? GLS or FedEx? Do you require priority overnight shipping or standard overnight shipping? The draft NPDES permit is attached, the true effective date is 9/1/24. Thanks, Matt Anderson Laboratory Manager Public Utilities 35 Prado Road, San Luis Obispo, CA 93401-7314 E manderson@slocity.org T 805.781.7242 C 805.540.8267 slocity.org Stay connected with the City by signing up for e-notifications CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential, proprietary and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments and the reply from your system. If you are not the intended recipient, you are hereby notified that any disclosure, use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential, proprietary and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments and the reply from your system. If you are not the intended recipient, you are hereby notified that any disclosure, use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential, proprietary and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments and the reply from your system. If you are not the intended recipient, you are hereby notified that any disclosure, use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential, proprietary and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments and the reply from your system. If you are not the intended recipient, you are hereby notified that any disclosure, use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. You don't often get email from manderso@slocity.org. Learn why this is important 100 CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential, proprietary and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments and the reply from your system. If you are not the intended recipient, you are hereby notified that any disclosure, use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential, proprietary and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments and the reply from your system. If you are not the intended recipient, you are hereby notified that any disclosure, use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential, proprietary and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments and the reply from your system. If you are not the intended recipient, you are hereby notified that any disclosure, use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. CONFIDENTIALITY NOTICE: The contents of this email message and any attachments are intended solely for the addressee(s) and may contain confidential, proprietary and/or privileged information and may be legally protected from disclosure. If you are not the intended recipient of this message or their agent, or if this message has been addressed to you in error, please immediately alert the sender by reply email and then delete this message and any attachments and the reply from your system. If you are not the intended recipient, you are hereby notified that any disclosure, use, dissemination, copying, or storage of this message or its attachments is strictly prohibited. 101 From:Anderson, Matt Sent:Friday, August 2, 2024 7:20 AM To:Chen, Bryan; Parsons, Patrice; Duncan, Tanner; Rose, Jill Subject:FW: TRANSMITTAL OF WASTE DISCHARGE REQUIREMENTS ORDER R3-2024-0001, NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT CA0049224 AND TIME SCHEDULE ORDER (TSO) R3-2024-0021 – CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY Attachments:SLO Final Order 2024-0001 and TSO 2024-0021 Transmittal Letter.pdf; Order R3-2024-0001.pdf; TSO R3-2024-0021.pdf Not the final countdown, but the Final Order. - Matt From: Crable, Sarah@Waterboards <Sarah.Crable@Waterboards.ca.gov> Sent: Thursday, August 1, 2024 5:25 PM To: McGrath, Patrick <pmcgrath@slocity.org> Cc: Floyd, Aaron <afloyd@slocity.org>; Lehman, Chris <clehman@slocity.org>; Barcenas, Miguel <MBarcena@slocity.org>; Anderson, Matt <manderso@slocity.org>; alabarre@co.slo.ca.us; breely@co.slo.ca.us; Janet Parrish <Parrish.Janet@epa.gov>; Elizabeth Sablad <Sablad.Elizabeth@epa.gov>; Amelia Whitson <Whitson.Amelia@epa.gov>; Froelich, Sophie@Waterboards <Sophie.Froelich@Waterboards.ca.gov>; Waggoner, Claire@Waterboards <Claire.Waggoner@waterboards.ca.gov>; Chand, Gurgagn@Waterboards <Gurgagn.Chand@Waterboards.ca.gov>; Densmore, Jeff@Waterboards <jeff.densmore@waterboards.ca.gov>; Souza, Kurt@Waterboards <Kurt.Souza@waterboards.ca.gov>; Cunningham, Jason@Waterboards <Jason.Cunningham@Waterboards.ca.gov>; Barnard, Randy@Waterboards <Randy.Barnard@waterboards.ca.gov>; hagemann.associates@gmail.com; dchisam@smmwc.com; Steph Wald <steph@creeklands.org>; Packard, Harvey@Waterboards <Harvey.Packard@waterboards.ca.gov>; Wyatt-Mair, Arwen@Waterboards <Arwen.WyattMair@waterboards.ca.gov>; Crable, Sarah@Waterboards <Sarah.Crable@Waterboards.ca.gov>; Bishop, James@Waterboards <James.Bishop@Waterboards.ca.gov>; Lemoine, Leah@Waterboards <Leah.Lemoine@Waterboards.ca.gov>; Vance, Julie@Wildlife <Julie.Vance@wildlife.ca.gov>; Hickey, Teri@Wildlife <Teri.Hickey@wildlife.ca.gov>; thomas.coleman@noaa.gov; R9NPDES@epa.gov; WB-DIT-DMR <DMR@waterboards.ca.gov>; icis-npdes@pgenv.com; WB-DWQ-NPDES_Wastewater <NPDES_Wastewater@waterboards.ca.gov> Subject: TRANSMITTAL OF WASTE DISCHARGE REQUIREMENTS ORDER R3-2024-0001, NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT CA0049224 AND TIME SCHEDULE ORDER (TSO) R3-2024-0021 – CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Good afternoon Mr. McGrath, Please see the attached transmittal letter and signed order for the recent adoption of Waste Discharge Requirements Order No. R3-2024-0001, NPDES Permit No. CA0049224, and signed time schedule order No. R3-2024-0021 for the City of San Luis Obispo Water Resource Recovery Please let me know if you have any questions. Thank you, Sarah 102 Sarah E. Crable, P.E. Water Resource Control Engineer, NPDES Program Central Coast Regional Water Quality Control Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401 (805) 549-3706 | sarah.crable@waterboards.gov 104 From:Patrick McGrath <eids.fa.sender@workflow.email.us-ashburn-1.ocs.oraclecloud.com> Sent:Monday, July 8, 2024 4:35 PM To:McGrath, Patrick Subject:FYI: Document (Requester Change Order) 617251 (Requisition 34233) Changed Attachments:PO_617251_7.pdf This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Access this task in the Workspace Application Document (Requester Change Order) 617251 (Requisition 34233) Changed Details Assignee Daniel Clancy Patrick McGrath From Patrick McGrath Assigned Date 07/08/2024 16.35 Expiration Date 08/07/2024 16.35 Task Number 2423083 Sold-to Legal Entity City of San Luis Obispo Order 617251 Procurement BU City of San Luis Obispo Buyer Daniel Clancy Justification Change Order Details Change Order 7 Description Blanket PO - Biosolids Initiating Party Requester Creation Date 07/08/2024 16.14 New Order Amount 614,613.34 USD Order Details Supplier Engel & Gray, Inc Supplier Site Main Ship-to Location Water Resource Recovery Supplier Order Description FY Open PO - 23-24 - Blanket PO - Biosolid Hauling Note to Supplier FY Open PO - 23-24 - Blanket PO - Biosolid Hauling - PO for attached FY 23-24 Open PO - This is an estimate PO and is not a guarantee the City will purchase the total amount Requisitioning BU City of San Luis Obispo Requisition 34233 Requester Patrick McGrath 105 Cost Center 6104 Attachments PO_617251_7.pdf DRAFTPurchase Order 617251 Order Date 18-AUG-2023 Change Order 7 Change Order Date 08-JUL-2024 Revision 4 Ordered 614,613.34 USD Order Amount Before Change 600,000.00 USD Net Order Amount Changed 14,613.34 USD INCLUDE PURCHASE ORDER NUMBER ON ALL INVOICES & CORRESPONDENCE SEND ALL INVOICES TO AP@SLOCITY.ORG INCLUDE DELIVER TO CITY STAFF CONTACT NAME ON ALL INVOICES Sold To City of San Luis Obispo 990 Palm Street SAN LUIS OBISPO, CA 93401 Supplier Engel & Gray, Inc 745 W. Betteravia Rd. SANTA MARIA, CA 93454SANTA BARBARA Bill To City of San Luis Obispo 990 Palm Street SAN LUIS OBISPO, CA 93401SAN LUIS OBISPO UNITED STATES Ship To 35 Prado Road SAN LUIS OBISPO, CA 93401SAN LUIS OBISPO UNITED STATES Notes USD = US Dollar FY Open PO - 23-24 - Blanket PO - Biosolid Hauling - PO for attached FY 23-24 Open PO - This is an estimate PO and is not a guarantee the City will purchase the total amount Customer Account Number Supplier Number Payment Terms Freight Terms FOB Shipping Method 10193 Net 30 Destination Confirm To Deliver To Contact Daniel Clancy Patrick McGrath Phone 1-805-781-7510 Line Item Price Quantity UOM Ordered Taxable 1 Blanket PO - Biosolid Hauling 614,613.34 Promised 614,613.34 08/23/2023 Requested 08/24/2023 Requested and Promised Dates correspond to the date of arrival at the Ship-to Location. Line Total 614,613.34 Total 614,613.34 1 DRAFTPurchase Order 617251 Change Order 7 2 DRAFTPurchase Order 617251 Proprietary and Confidential Contract Terms and Conditions Purchase Order Terms and Conditions Standard Purchase Order Terms & Conditions 1. Acceptance. By delivering the ordered goods or commencing performance under this Purchase Order, ("Order") supplier agrees to the general terms, specifications, and conditions in or referenced by this document. If supplier and The City of San Luis Obispo ("City") have entered into a contract outside of this Order, the terms and conditions set forth in the contract shall prevail. Supplier's additional or different terms and conditions are expressly excluded from this Order and the City does not agree to such terms or conditions, unless such agreement is made expressly, in writing by the City's authorized representative, or a contract has been signed outside of this Order between the Supplier and The City. 2. Business License & Tax. Supplier must have a valid City of San Luis Obispo business tax certificate prior to the execution of the contract. Additional information regarding the City's business tax program may be obtained by calling (805) 781-7134. 3. Ability to Perform. Supplier warrants that it possesses, or has arranged through subcontracts, all capital and other equipment, labor, materials, and licenses necessary to carry out and complete the work hereunder in compliance with any and all federal, state, county, city, and special district laws, ordinances, and regulations. 4. Warranties. Supplier warrants that all goods delivered will be free from defects in workmanship, material, and manufacture; are new (not refurbished or reconditioned) unless otherwise stated in this Order; are of merchantable quality and fit for the purpose intended by the City to the extent that purpose has been disclosed to Supplier; complies with the requirements of this Order; and complies with all applicable laws and regulations. Supplier also warrants that all services performed under this Order shall be rendered in a good and workmanlike manner by skilled personnel in compliance with all applicable laws and regulations. 5. Changes. No change or modification in terms may be made without express authorization, in writing by the City's authorized representative. 6. Delivery. Supplier agrees that time is of the essence to delivery and any other performance required under this Order. No charge for delivery, parcel post, packing, cartage, insurance, license fees, permits, or any other purpose will be paid by the City unless it is expressly included on the face of this Order. Supplier must arrange for the lowest- cost transportation and prepay and add freight to its invoice. If delivery is made by a carrier, an itemized delivery ticket must be attached to the outside of the package. Each container or package must be marked with the Order number. 7. Laws to be Observed. Supplier shall keep itself fully informed of and shall observe and comply with all applicable state and federal laws and county and City of San Luis Obispo ordinances, regulations and adopted codes during its performance of the work. 8. Payment of Taxes. The contract prices shall include full compensation for all taxes that Supplier is required to pay. 9. Permits and Licenses. Supplier shall procure all permits and licenses, pay all charges and fees, and give all notices necessary. 10. Safety Provisions. Supplier shall conform to the rules and regulations pertaining to safety established by OSHA and the California Division of Industrial Safety Public and Employee Safety. Whenever Supplier's operations create a condition hazardous to the public or City employees, it shall, at its expense and without cost to the City, furnish, erect and maintain such fences, temporary railings, barricades, lights, signs and other devices and take such other protective measures as are necessary to prevent accidents or damage or injury to the public and employees. 11. Preservation of City Property. Supplier shall provide and install suitable safeguards, approved by the City, to protect City property from injury or damage. If City property is injured or damaged as a result of Supplier's operations, it shall be replaced or restored at Supplier's expense. The facilities shall be replaced or restored to a condition as good as when the Supplier began work 12. Immigration Act of 1986. Supplier warrants on behalf of itself and all sub-suppliers engaged for the performance of this work that only persons authorized to work in the United States pursuant to the Immigration Reform and Control Act of 1986 and other applicable laws shall be employed in the performance of the work hereunder. 13. Supplier Non-Discrimination. In the performance of this work, Supplier agrees that it will not engage in, nor permit such sub-suppliers as it may employ, to engage in discrimination in the employment of persons because of age, race, color, sex, national origin or ancestry, sexual orientation, or religion of such persons. 14. Work Delays. Should Supplier be obstructed or delayed in the work required to be done hereunder by changes in the work or by any default, act, or omission of the City, or by strikes, fire, earthquake, or any other Act of God, or by the inability to obtain materials, equipment, or labor due to federal government restrictions arising out of defense or war programs, then the time of completion may, at the City's sole option, be extended for such periods as may be agreed upon by the City and the Supplier. 15. Payment Terms. The City's payment terms are 30 days from the receipt of an original invoice and acceptance by the City of the services provided by Supplier (Net 30). 16. Inspection. Supplier shall furnish City with every reasonable opportunity for City to ascertain that the services of Supplier are being performed in accordance with the requirements and intentions of this contract. All work done and all materials furnished, if any, shall be subject to the City's inspection and approval. The inspection of such work shall not relieve Supplier of any of its obligations to fulfill its contract requirements. 17. Audit. The City shall have the option of inspecting and/or auditing all records and other written materials used by Supplier in preparing its invoices to City as a condition precedent to any payment to Supplier. 18. Interests of Supplier. Supplier covenants that it presently has no interest, and shall not acquire any interest direct or indirect or otherwise, which would conflict in any manner or degree with the performance of the work hereunder. Supplier further covenants that, in the performance of this work, no sub-Supplier or person having such an interest shall be employed. Supplier certifies that no one who has or will have any financial interest in performing this work is an officer or employee of the City. It is hereby expressly agreed that, in the performance of the work hereunder, Supplier shall at all times be deemed an independent Supplier and not an agent or employee of the City. 19. Hold Harmless and Indemnification. (a) Non-design, non-construction Professional Services: To the fullest extent permitted by law (including, but not limited to California Civil Code Sections 2782 and 2782.8), Consultant shall indemnify, defend, and hold harmless the City, and its elected officials, officers, employees, volunteers, and agents ("City Indemnitees"), from and against any and all causes of action, claims, liabilities, obligations, judgments, or damages, including reasonable legal counsels' fees and costs of litigation ("claims"), arising out of the Consultant's performance or Consultant's failure to perform its obligations under this Agreement or out of the operations conducted by Consultant, including the City's active or passive negligence, except for such loss or damage arising from the sole negligence or willful misconduct of the 3 Purchase Order 617251 Proprietary and Confidential City. In the event the City Indemnitees are made a party to any action, lawsuit, or other adversarial proceeding arising from Consultant's performance of this Agreement, the Consultant shall provide a defense to the City Indemnitees or at the City's option, reimburse the City Indemnitees their costs of defense, including reasonable legal fees, incurred in defense of such claims. (b) Non-design, construction Professional Services: To the extent the Scope of Services involve a "construction contract" as that phrase is used in Civil Code Section 2783, this paragraph shall apply in place of paragraph A. To the fullest extent permitted by law (including, but not limited to California Civil Code Sections 2782 and 2782.8), Consultant shall indemnify, defend, and hold harmless the City, and its elected officials, officers, employees, volunteers, and agents ("City Indemnitees"), from and against any and all causes of action, claims, liabilities, obligations, judgments, or damages, including reasonable legal counsels' fees and costs of litigation ("claims"), arising out of the Consultant's performance or Consultant's failure to perform its obligations under this Agreement or out of the operations conducted by Consultant, except for such loss or damage arising from the active negligence, sole negligence or willful misconduct of the City. In the event the City Indemnitees are made a party to any action, lawsuit, or other adversarial proceeding arising from Consultant's performance of this Agreement, the Consultant shall provide a defense to the City Indemnitees or at the City's option, reimburse the City Indemnitees their costs of defense, including reasonable legal fees, incurred in defense of such claims. (c) Design Professional Services: In the event Consultant is a "design professional", and the Scope of Services require Consultant to provide "design professional services" as those phrases are used in Civil Code Section 2782.8, this paragraph shall apply in place of paragraphs A or B. To the fullest extent permitted by law (including, but not limited to California Civil Code Sections 2782 and 2782.8) Consultant shall indemnify, defend and hold harmless the City and its elected officials, officers, employees, volunteers and agents ("City Indemnitees"), from and against all claims, damages, injuries, losses, and expenses including costs, attorney fees, expert consultant and expert witness fees arising out of, pertaining to or relating to, the negligence, recklessness or willful misconduct of Consultant, except to the extent caused by the sole negligence, active negligence or willful misconduct of the City. Negligence, recklessness or willful misconduct of any subcontractor employed by Consultant shall be conclusively deemed to be the negligence, recklessness or willful misconduct of Consultant unless adequately corrected by Consultant. In the event the City Indemnitees are made a party to any action, lawsuit, or other adversarial proceeding arising from Consultant's performance of this Agreement, the Consultant shall provide a defense to the City Indemnitees or at the City's option, reimburse the City Indemnitees their costs of defense, including reasonable legal fees, incurred in defense of such claims. In no event shall the cost to defend charged to Consultant under this paragraph exceed Consultant's proportionate percentage of fault. However, notwithstanding the previous sentence, in the event one or more defendants are unable to pay its share of defense costs due to bankruptcy or dissolution of the business, Consultant shall meet and confer with other parties regarding unpaid defense costs. (d) The review, acceptance or approval of the Consultant's work or work product by any indemnified party shall not affect, relieve or reduce the Consultant's indemnification or defense obligations. This Section survives completion of the services or the termination of this contract. The provisions of this Section are not limited by and do not affect the provisions of this contract relating to insurance. 20. Contract Assignment. Supplier shall not assign, transfer, convey or otherwise dispose of the contract, or its right, title or interest, or its power to execute such a contract to any individual or business entity of any kind without the previous written consent of the City. 21. Termination for Convenience. The City may terminate all or part of this Agreement for any or no reason at any time by giving 30 days written notice to Contractor. Should the City terminate this Agreement for convenience, the City shall be liable as follows: (a) for standard or off-the-shelf products, a reasonable restocking charge not to exceed ten (10) percent of the total purchase price; (b) for custom products, the less of a reasonable price for the raw materials, components work in progress and any finished units on hand or the price per unit reflected on this Agreement. For termination of any services pursuant to this Agreement, the City's liability will be the lesser of a reasonable price for the services rendered prior to termination, or the price for the services reflected on this Agreement. Upon termination notice from the City, Contractor must, unless otherwise directed, cease work and follow the City's directions as to work in progress and finished goods. 22. Termination. If during the term of the contract, the City determines that the Contractor is not faithfully abiding by any term or condition contained herein, the City may notify the Contractor in writing of such defect or failure to perform. This notice must give the Contractor a 10 (ten) calendar day notice of time thereafter in which to perform said work or cure the deficiency. If the Contractor has not performed the work or cured the deficiency within the ten days specified in the notice, such shall constitute a breach of the contract and the City may terminate the contract immediately by written notice to the Contractor to said effect.Thereafter, neither party shall have any further duties, obligations, responsibilities, or rights under the contract except, however, any and all obligations of the Contractor's surety shall remain in full force and effect, and shall not be extinguished, reduced, or in any manner waived by the terminations thereof. In said event, the Contractor shall be entitled to the reasonable value of its services performed from the beginning date in which the breach occurs up to the day it received the City's Notice of Termination, minus any offset from such payment representing the City's damages from such breach."Reasonable value" includes fees or charges for goods or services as of the last milestone or task satisfactorily delivered or completed by the Contractor as may be set forth in the Agreement payment schedule; compensation for any other work, services or goods performed or provided by the Contractor shall be based solely on the City's assessment of the value of the work-in-progress in completing the overall work scope. The City reserves the right to delay any such payment until completion or confirmed abandonment of the project, as may be determined in the City's sole discretion, so as to permit a full and complete accounting of costs.In no event, however, shall the Contractor be entitled to receive in excess of the compensation quoted in its proposal. 23. Ownership of Materials. All original drawings, plan documents and other materials prepared by or in possession of Supplier as part of the work or services under these specifications shall become the permanent property of the City, and shall be delivered to the City upon demand. 24. Release of Reports and Information. Any reports, information, data, or other material is given to, prepared by or assembled by Supplier as part of the work or services under these specifications shall be the property of City, and shall not be made available to any individual or organization by Supplier without the prior written approval of the City. 25. Copies of Reports and Information. If the City requests additional copies of reports, drawings, specifications, or any other material in addition to what Supplier is required to furnish in limited quantities as part of the work or services under these specifications, Supplier shall provide such additional copies as are requested, and City shall compensate Supplier for the costs of duplicating of such copies at the Supplier's direct expense. 26. Insurance. Supplier shall procure and maintain for the duration of the Order insurance that is sufficient in scope and amount to permit Supplier to pay in the ordinary course of business against claims for injuries to persons or damages to property that may arise from or in connection with the performance of the work hereunder by Supplier, its agents, representatives, employees or sub-contractors. Supplier will maintain Workers Compensation insurance at statutory levels covering all employees who perform work under this Order. Additional Public Works Construction Purchase Order Terms & Conditions 1. Compensation for Authorized Additional Expenses. To receive compensation for additional expenses outside the scope of the project work, the Supplier shall obtain prior written authoriza-tion from the City to incur those expenses. Compensa-tion for these addition-al expenses shall include time and materials. 2. Payment Terms. The supplier may request one progress payment each month for work satisfactorily completed and accepted by the City. The City shall issue payment within 30 days. The City shall withhold 10 percent of each progress payment as retention to ensure resolution of any stop notices or liens. The City shall release this retention 35 days after filing a notice of completion. 3. Faithful Performance Bond. The supplier shall furnish a surety bond in the amount of 125 percent of the contract price guaranteeing the faithful performance of the contract, including any attorney's fees or other collection costs. 4. Work in the Right-of-Way or on City Property. For work on City managed property, the supplier/ consultant shall obtain a no-fee encroachment permit. A Traffic Control Plan and Water Pollution Control Plan shall be submitted and approved prior to issuance of the permit unless determined by the City not to be required. 5. Prevailing Wage. The supplier and any subcontractors are required to pay prevailing wage and must be registered with the Department of Industrial Relations pursuant to Section 1725.5 of the Labor Code. 6. Insurance. The supplier shall procure and maintain for the duration of the contract insurance against claims for injuries to persons or dam-ages to property which may arise from or in connection with the performance of the work hereunder by the supplier, its agents, representatives, employees or subs. Minimum Scope of Insurance. Coverage shall be at least as broad as: 4 Purchase Order 617251 Proprietary and Confidential a. Insurance Services Office Commercial General Liability coverage (occurrence form CG 20 10 Prior to 1993 or CG 20 10 07 04 with CG 20 37 10 01 or the exact equivalent as determined by the City). b. Insurance Services Office form number CA 0001 (Ed. 1/87) covering Automobile Liability, code 1 (any auto). c. Workers' Compensation insurance as required by the State of California and Employer's Liability Insurance. Minimum Limits of Insurance. The supplier shall maintain limits no less than: a. General Liability: $1,000,000 per occurrence for bodily injury, personal injury and property damage. If Commercial General Liability or other forms with a general aggregate limit is used, either the general aggregate limit shall apply separately to this project/location or the general aggregate limit shall be twice the required occurrence limit. b. Automobile Liability: $1,000,000 per accident for bodily injury and property damage. c. Employer's Liability: $1,000,000 per accident for bodily injury or disease. d. Deductibles and Self-Insured Retentions. Any deductibles or self-insured retentions must be declared to and approved by the City. At the option of the City, either: the insurer shall reduce or eliminate such deductibles or self-insured retentions as respects the City, its officers, officials, employees, and volunteers; or the supplier shall procure a bond guaranteeing payment of losses and related investigations, claim administration and defense expenses. Other Insurance Provisions. The general liability and automobile liability policies are to contain, or be endorsed to contain, the following provi-sions: a. The City, its officers, officials, employees, agents, and volunteers are to be covered as insureds as respects: liability arising out of activities performed by or on behalf of the supplier; products and completed operations of the supplier; premises owned, occupied or used by the supplier; or automobiles owned leased, hired or borrowed by the supplier. The coverage shall contain no special limitations on the scope of protection afforded to the City, its officers, officials, employees, agents or volunteers. b. For any claims related to this project, the supplier's insurance coverage shall be primary insurance as respects the City, its officers, officials, employees, agents, and volunteers. Any insur-ance or self- insurance maintained by the City, its officers, offi-cials, employees, agents or volunteers shall be excess of the supplier's insurance and shall not contribute with it. c. Any failure to comply with reporting or other provisions of the policies including breaches of warranties shall not affect coverage provided to the City, its officers, officials, employees, agents or volunteers. d. The supplier's insurance shall apply separately to each insured against whom claim is made or suit is brought, except with respect to the limits of the insurer's liability. e. Each insurance policy required by this clause shall be endorsed to state that coverage shall not be suspended, voided, canceled by either party, reduced in coverage or in limits except after thirty (30) days' prior written notice by certified mail, return receipt requested, has been given to the City. Acceptability of Insurers. Insurance is to be placed with insurers with a current A.M. Best's rating of no less than A:VII. Verification of Coverage. The supplier shall furnish the City with a certificate of insurance showing required coverage. Original endorse-ments affecting general liability and automobile liability coverage are also required by this clause. The endorsements are to be signed by a person authorized by that insurer to bind coverage on its behalf. All endorsements are to be received and approved by the City before work commences. Subcontractors. The supplier shall include all subcontractors as insured under its policies or shall furnish separate certifi-cates and endorsements for each subcontractor. All coverages for subcontractors shall be subject to all of the requirements stated herein. 5 106 From:workflowsystem <eids.fa.sender@workflow.email.us-ashburn-1.ocs.oraclecloud.com> Sent:Monday, July 8, 2024 4:16 PM To:Holt, Timothy Subject:Action Required: Approve Requester Change Order 617251-7 Attachments:PO_617251_0_Deviations.pdf; PO_617251_1_Deviations.pdf; PO_617251_7.pdf; PO_617251_2 _Deviations.pdf; PO_617251_3_Deviations.pdf; PO_617251_4_Deviations.pdf; PO_617251_5 _Deviations.pdf; PO_617251_6_Deviations.pdf; PO_617251_7_Deviations.pdf This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Access this task in the Workspace Application 107 Change Order Approval $614,613.34 Engel & Gray, Inc Change Description: Blanket PO - Biosolids Initiated By: Patrick McGrath Approve Reject Request Info Buyer Daniel Clancy Requester Patrick McGrath Requisition 34233 Description FY Open PO - 23-24 - Blanket PO - Biosolid Hauling Amount Changed +$14,613.34 Change Order 617251-7 Justification Required services Changed Lines Blanket PO - Biosolid Hauling Amount Changed: +$14,613.34 Requester: McGrath, Patrick Requisition: 34233 Charge Account: $614,613.34 Approvals 07/08/2024 4:15 PM Assigned to Timothy Holt 07/08/2024 4:15 PM Assigned to Daniel Clancy 07/08/2024 4:15 PM Submitted by Patrick McGrath 108 PO_617251_5_Deviations.pdf PO_617251_6_Deviations.pdf PO_617251_7_Deviations.pdf PO_617251_2_Deviations.pdf PO_617251_3_Deviations.pdf PO_617251_4_Deviations.pdf PO_617251_0_Deviations.pdf PO_617251_1_Deviations.pdf PO_617251_7.pdf Approve Reject Request Info View Change Order Task Details Contract Standards Deviations Standard Purchase Order 617251, 0 Proprietary and Confidential 1 Standard Purchase Order 617251, 0: Contract Standards Deviations - 18-Aug-2023 Supplier Engel & Gray, Inc Supplier Site Main Buyer Clancy, Daniel "Dan"Amount 180,000.00 USD Business Unit City of San Luis Obispo Contract Template Standard Purchase Order Terms and Conditions Contract Standards Deviations Standard Purchase Order 617251, 0 Proprietary and Confidential 2 Deviation Summary Clause Deviations Category Deviation Section Clause Title No clause deviations. Contract Standards Deviations Standard Purchase Order 617251, 1 Proprietary and Confidential 1 Standard Purchase Order 617251, 1: Contract Standards Deviations - 19-Jan-2024 Supplier Engel & Gray, Inc Supplier Site Main Buyer Clancy, Daniel "Dan"Amount 180,000.00 USD Business Unit City of San Luis Obispo Contract Template Standard Purchase Order Terms and Conditions Contract Standards Deviations Standard Purchase Order 617251, 1 Proprietary and Confidential 2 Deviation Summary Clause Deviations Category Deviation Section Clause Title No clause deviations. Contract Standards Deviations Standard Purchase Order 617251, 2 Proprietary and Confidential 1 Standard Purchase Order 617251, 2: Contract Standards Deviations - 31-Jan-2024 Supplier Engel & Gray, Inc Supplier Site Main Buyer Clancy, Daniel "Dan"Amount 180,000.00 USD Business Unit City of San Luis Obispo Contract Template Standard Purchase Order Terms and Conditions Contract Standards Deviations Standard Purchase Order 617251, 2 Proprietary and Confidential 2 Deviation Summary Clause Deviations Category Deviation Section Clause Title No clause deviations. Contract Standards Deviations Standard Purchase Order 617251, 3 Proprietary and Confidential 1 Standard Purchase Order 617251, 3: Contract Standards Deviations - 14-Feb-2024 Supplier Engel & Gray, Inc Supplier Site Main Buyer Clancy, Daniel "Dan"Amount 300,000.00 USD Business Unit City of San Luis Obispo Contract Template Standard Purchase Order Terms and Conditions Contract Standards Deviations Standard Purchase Order 617251, 3 Proprietary and Confidential 2 Deviation Summary Clause Deviations Category Deviation Section Clause Title No clause deviations. Contract Standards Deviations Standard Purchase Order 617251, 4 Proprietary and Confidential 1 Standard Purchase Order 617251, 4: Contract Standards Deviations - 10-Jun-2024 Supplier Engel & Gray, Inc Supplier Site Main Buyer Clancy, Daniel "Dan"Amount 500,000.00 USD Business Unit City of San Luis Obispo Contract Template Standard Purchase Order Terms and Conditions Contract Standards Deviations Standard Purchase Order 617251, 4 Proprietary and Confidential 2 Deviation Summary Clause Deviations Category Deviation Section Clause Title No clause deviations. Contract Standards Deviations Standard Purchase Order 617251, 5 Proprietary and Confidential 1 Standard Purchase Order 617251, 5: Contract Standards Deviations - 11-Jun-2024 Supplier Engel & Gray, Inc Supplier Site Main Buyer Clancy, Daniel "Dan"Amount 500,000.00 USD Business Unit City of San Luis Obispo Contract Template Standard Purchase Order Terms and Conditions Contract Standards Deviations Standard Purchase Order 617251, 5 Proprietary and Confidential 2 Deviation Summary Clause Deviations Category Deviation Section Clause Title No clause deviations. Contract Standards Deviations Standard Purchase Order 617251, 6 Proprietary and Confidential 1 Standard Purchase Order 617251, 6: Contract Standards Deviations - 20-Jun-2024 Supplier Engel & Gray, Inc Supplier Site Main Buyer Clancy, Daniel "Dan"Amount 500,000.00 USD Business Unit City of San Luis Obispo Contract Template Standard Purchase Order Terms and Conditions Contract Standards Deviations Standard Purchase Order 617251, 6 Proprietary and Confidential 2 Deviation Summary Clause Deviations Category Deviation Section Clause Title No clause deviations. Contract Standards Deviations Standard Purchase Order 617251, 7 Proprietary and Confidential 1 Standard Purchase Order 617251, 7: Contract Standards Deviations - 08-Jul-2024 Supplier Engel & Gray, Inc Supplier Site Main Buyer Clancy, Daniel "Dan"Amount 600,000.00 USD Business Unit City of San Luis Obispo Contract Template Standard Purchase Order Terms and Conditions Contract Standards Deviations Standard Purchase Order 617251, 7 Proprietary and Confidential 2 Deviation Summary Clause Deviations Category Deviation Section Clause Title No clause deviations. 109 From:workflowsystem <eids.fa.sender@workflow.email.us-ashburn-1.ocs.oraclecloud.com> Sent:Monday, July 8, 2024 4:16 PM To:McGrath, Patrick Subject:FYI: Approve Requester Change Order 617251-7 Attachments:PO_617251_0_Deviations.pdf; PO_617251_1_Deviations.pdf; PO_617251_7.pdf; PO_617251_2 _Deviations.pdf; PO_617251_3_Deviations.pdf; PO_617251_4_Deviations.pdf; PO_617251_5 _Deviations.pdf; PO_617251_6_Deviations.pdf; PO_617251_7_Deviations.pdf This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Access this task in the Workspace Application 110 Change Order Approval $614,613.34 Engel & Gray, Inc Change Description: Blanket PO - Biosolids Initiated By: Patrick McGrath Buyer Daniel Clancy Requester Patrick McGrath Requisition 34233 Description FY Open PO - 23-24 - Blanket PO - Biosolid Hauling Amount Changed +$14,613.34 Change Order 617251-7 Justification Required services Changed Lines Blanket PO - Biosolid Hauling Amount Changed: +$14,613.34 Requester: McGrath, Patrick Requisition: 34233 Charge Account: $614,613.34 Approvals 07/08/2024 16.15 Assigned to Timothy Holt 07/08/2024 16.15 Assigned to Daniel Clancy 07/08/2024 16.15 Submitted by Patrick McGrath PO_617251_5_Deviations.pdf PO_617251_6_Deviations.pdf 111 PO_617251_7_Deviations.pdf PO_617251_2_Deviations.pdf PO_617251_3_Deviations.pdf PO_617251_4_Deviations.pdf PO_617251_0_Deviations.pdf PO_617251_1_Deviations.pdf PO_617251_7.pdf View Change Order Task Details 112 From:Anderson, Matt Sent:Tuesday, June 25, 2024 4:36 PM To:WRRF_LAB Subject:FW: New NPDES Permit and TSO Adopted Attachments:draft_tso_slo_R3-2024-0021.docx; r3-2024-0001.pdf From: Lehman, Chris <clehman@slocity.org> Sent: Friday, June 21, 2024 8:33 AM To: McGrath, Patrick <pmcgrath@slocity.org>; Anderson, Matt <manderso@slocity.org>; Claxton, Christina <cclaxton@slocity.org> Cc: Floyd, Aaron <afloyd@slocity.org>; Barcenas, Miguel <MBarcena@slocity.org>; Boerman, Mychal <mboerman@slocity.org> Subject: New NPDES Permit and TSO Adopted Please share with your staff. The new SLO WRRF NPDES permit and TSO were adopted yesterday and will be effective on September 1, 2024. We will work with CASA, LWA, and a collective of agencies to take a coordinated approach to arguing against the new effluent salt limits as we carry out the mandatory deliverables identified in the TSO. The pond plants with WDRs are in an especially tough spot, including Atascadero, Santa Maria, Templeton, etc. Locally in SLO, we will advocate for a Basin Plan amendment and site-specific objectives. More to come on all of this in the coming months. Please ensure your staff have access to and begin to review the attached so we are prepared come September. Thanks, Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications STATE OF CALIFORNIA CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401 DRAFT TIME SCHEDULE ORDER R3-2024-0021 REQUIRING THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY TO COMPLY WITH REQUIREMENTS PRESCRIBED IN NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT NO. CA0049224, ORDER R3-2024-0001 The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 1. The City of San Luis Obispo (Discharger) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (Facility), a publicly owned treatment works (POTW). The Facility is located at 35 Prado Road, San Luis Obispo, San Luis Obispo County. 2. Treatment at the Facility currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four Modified Ludzack-Ettinger (MLE) bioreactors, hollowfiber membranes, and ultraviolet (UV) disinfection. The biosolids handling unit consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. 3. On [placeholder for adoption date], the Central Coast Water Board adopted Waste Discharge Requirements Order R3-2024-0001, National Pollutant Discharge Elimination System (NPDES) Permit CA0049224. Order R3-2024-0001 regulates the discharge of tertiary treated effluent from the Facility to San Luis Obispo Creek, a water of the United States, located within the Estero Bay Hydrologic Unit. The effective date of Order R3-2024-0001 is [placeholder for effective date]. 4. Analysis of the Discharger’s effluent monitoring data from December 2014 through December 2022 found that the Discharger’s effluent had a reasonable potential to cause or contribute to exceedances of water quality objectives for total dissolved solids (TDS), chloride, sodium, sulfate, and molybdenum, and therefore warranted the establishment of effluent limitations for those parameters. 5. Order R3-2024-0001 prescribes the following new effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum. Table 1: Final effluent limitations in Order R3-2024-0001 Parameter Units Average Annual1 Average Monthly TDS mg/L 650 Chloride mg/L 100 DRAFT TSO R3-2024-0021 -2- September 1, 2024 1Compliance is determined using a 12-month running mean. NEED FOR TIME SCHEDULE ORDER AND REGULATORY REQUIREMENTS 6. The Discharger is unable to consistently comply with the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum, which were not effluent limits in the prior permit and are new to Order R3-2024-0001. In its January 11, 2024 comment letter on draft Order R3-2024-0001, the Discharger asked the Central Coast Water Board to include an in-permit compliance schedule to allow the Discharger time to develop and implement improvements to comply with the new effluent limits. 7. State Water Resources Control Board Resolution 2008-0025, Policy for Compliance Schedules in National Pollutant Discharge Elimination System Permits (Compliance Schedule Policy), was adopted on April 15, 2008. The Policy provides that in-permit compliance schedules should only be granted when additional time is needed to complete significant compliance actions to comply with new permit limitations implementing new, revised, or newly interpreted water quality objectives or criteria in water quality standards. The Compliance Schedule Policy defines the term “new, revised or newly interpreted water quality standard” to be standards adopted by the Central Coast Water Board after September 25, 1995. (Compliance Schedule Policy, p. 3, paragraph 1 subd. (d).) The Compliance Schedule Policy defines the term “newly interpreted water quality objective or criterion in a water quality standard,” as meaning: a narrative water quality objective or criterion that, when interpreted during NPDES permit development (using appropriate scientific information and consistent with state and federal law) to determine the permit limitations necessary to implement the objective, results in a numeric permit limitation more stringent than the limit in the prior NPDES permit issued to the discharger. Newly interpreted water quality objective or criterion in a water quality standard also includes a numeric or narrative water quality objective or criterion that is implemented with a permit limitation with which the discharger cannot comply because the pollutant was newly detected in the discharger’s effluent due to new analytical techniques that were developed after the prior permit was issued. (Id., p. 3, paragraph 1 subd. (e).) 8. The Water Quality Control Plan for the Central Coastal Basin (Basin Plan) includes numeric water quality objectives for TDS, chloride, sodium, sulfate, and molybdenum. Basin Plan Table 3-5 includes numeric mean surface water quality objectives for TDS, chloride, sodium, and sulfate specific to San Luis Obispo Creek. Table 3-2 includes the numeric water quality objective for molybdenum for waters with the agricultural supply beneficial use, which applies to San Luis Obispo Creek. These numeric water quality objectives were used in the analyses that found the Facility had reasonable potential to cause or contribute to exceedances of water quality objectives. These objectives have been part of the Basin Plan since at least 1994. Sodium mg/L 50 Sulfate mg/L 100 Molybdenum mg/L 0.01 DRAFT TSO R3-2024-0021 -3- September 1, 2024 9. The Discharger is not eligible for an in-permit compliance schedule because the water quality objectives used to establish the new effluent limitations for TDS, chloride, sodium, and sulfate in Order R3-2024-0001 were not new, revised, or newly interpreted water quality standards as that term is defined in the Compliance Schedule Policy. Similarly, the Discharger is not eligible for an in-permit compliance schedule for molybdenum because the water quality objective used to establish the new effluent limitation for molybdenum in Order R3-2024-0001 was not a new, revised, or newly interpreted water quality standard as that term is defined in the Compliance Schedule Policy. Although molybdenum is newly detected in the Discharger’s effluent through monitoring requirements established in the Discharger’s previous NPDES permit, Order R3-2014-0033, the analytical techniques were developed long before the prior permit was issued. 10. Considering the foregoing analysis, a time schedule order, issued pursuant to California Water Code (Water Code) sections 13300 and 13385(j)(3), is the appropriate mechanism to allow the Discharger additional time to comply with its effluent limitations in Order R3-2024-0001. 11. Section 13300 of the Water Code states: “Whenever a regional board finds that a discharge of waste is taking place or threatening to take place that violates or will violate requirements prescribed by the regional board, or the state board, or that the waste collection, treatment, or disposal facilities of a permittee are approaching capacity, the board may require the permittee to submit for approval of the board, with such modifications as it may deem necessary, a detailed time schedule of specific actions the permittee shall take in order to correct or prevent a violation of requirements.” 12. Water Code section 13385, subdivisions (h) and (i), require the Central Coast Water Board to impose mandatory minimum penalties upon dischargers that violate certain effluent limitations. Section 13385(j)(3)(A) exempts violations of an effluent limitation from mandatory minimum penalties "where the waste discharge is in compliance with … a time schedule order issued pursuant to Section 13300, if all of the [specified] requirements are met." (emphasis added). 13. Pursuant to Water Code section 13385 subdivision (j)(3)(B)(i), the Central Coast Water Board finds that, based on effluent monitoring data, the Discharger is not able to consistently comply with the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum in Order R3-2024-0001 while new or modified control measures are implemented to increase pollutant removal efficiency or reduce the amount of these pollutants the facility receives. The effluent limitations for these pollutants are new requirements for the Discharger, and a time schedule order will allow the Discharger time to assess discharges to the collection system, collect data, perform studies, and develop additional pretreatment and control options for molybdenum and high-concentration TDS, chloride, sodium, and sulfate dischargers within the city. In addition, the new or modified control measures cannot be designed, installed, and put into operation within 30 calendar days. 14. The Discharger intends to carry out source control measures by implementing a pollution prevention plan, performing a source identification study, and performing a pretreatment program local limits study. During these efforts, the Discharger may be temporarily unable to comply with the Order R3-2024-0001 final effluent limitations DRAFT TSO R3-2024-0021 -4- September 1, 2024 for TDS, chloride, sodium, sulfate, and molybdenum, and interim effluent limits are necessary. The period of this time schedule order is September 1, 2024, through August 31, 2029. 15. During the period of the time schedule order, the Discharger will continue to operate and discharge under all the limitations specified in Order R3-2024-0001 except for TDS, chloride, sodium, sulfate, and molybdenum. The Discharger will continue to report on all parameters as specified in Order R3-2024-0001. 16. Pursuant to Water Code section 13223, the Central Coast Water Board has delegated to its Executive Officer the authority to issue a time schedule order pursuant to Water Code section 13300. 17. Water Code section 13383 authorizes the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements for any person who owns or operates a publicly owned treatment works. In accordance with 40 C.F.R. sections 25.5 and 124.10 subd. (b)(1) and Water Code section 13378, the Central Coast Water Board publicly noticed this time schedule order from March 12, 2024 through April 11, 2024. No public comments were received. 18. Issuance of this time schedule order is exempt from provisions of the California Environmental Quality Act (Pub. Resources Code, section 21000 et seq.) (CEQA) pursuant to Water Code section 13389 because the adoption or modification of an NPDES permit for an existing source is statutorily exempt from CEQA, and this time schedule order only serves to implement an NPDES permit. (Pacific Water Conditioning Ass’n, Inc. v. City Council of City of Riverside (1977) 73 Cal. App. 3d 546, 555-556). Furthermore, this enforcement action is taken for the protection of the environment and as such is exempt from CEQA in accordance with section 15321, chapter 3, title 14, California Code of Regulations. MANDATORY MINIMUM PENALTIES 19. Pursuant to Water Code section 13385(j)(3), violations of the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum in Order R3-2024-0001 are not subject to Water Code section 13385 subdivisions (h) and (i) mandatory minimum penalties, provided the Discharger complies with all the requirements of this time schedule order and all the following conditions are met: a. The time schedule order specifies the actions that the Discharger is required to take in order to correct the violations that would otherwise be subject to subdivisions (h) and (i). b. The Central Coast Water Board finds that the Discharger is not able to consistently comply with one or more of the effluent limitations established in the waste discharge requirements applicable to the waste discharge for one of the reasons described in Water Code section 13385(j)(3)(B)(i)-(iv) (see Paragraph 12, supra). c. The Central Coast Water Board establishes a time schedule for bringing the waste discharge into compliance with the final effluent limitation that is as short as possible and does not exceed five years in length. d. For time schedules that exceed one year from the effective date of the time schedule order, the schedule shall include interim requirements and the dates for their achievement. The interim requirements shall include both of the following: DRAFT TSO R3-2024-0021 -5- September 1, 2024 i. Effluent limitations for the pollutant or pollutants of concern. ii. Actions and milestones leading to compliance with the effluent limitation. e. The Discharger has prepared and is implementing in a timely and proper manner or is required by the Central Coast Water Board to prepare and implement a pollution prevention plan pursuant to CWC section 13263.3. This time schedule order requires the Discharger to prepare, implement, and submit a pollution prevention plan for TDS, chloride, sodium, sulfate, and molybdenum. This time schedule order satisfies the above conditions a-e. 20. This time schedule order requires the Discharger to comply with a time schedule by August 31, 2029, that will allow the Discharger to achieve full compliance with TDS, chloride, sodium, sulfate, and molybdenum final effluent limitations in Order R3-2024- 0001. 21. This time schedule order includes performance-based interim effluent limitations that are based on the 97.22 percentile for results measured from 2015 to 2023 for TDS, chloride, sodium sulfate, and molybdenum as shown in Table 3. 22. The Central Coast Water Board expects that the Discharger can maintain compliance with the interim effluent limitations included in this time schedule order. Interim effluent limitations are established when compliance with the final effluent limitations cannot be achieved by the existing Facility. Discharge of pollutants in concentrations in excess of the final limitations in the permit, but in compliance with the interim effluent limitations, can significantly degrade water quality and adversely affect the beneficial uses of the receiving stream on a long-term basis. The interim effluent limitations, however, establish an enforceable ceiling value until compliance with the final effluent limitations can be achieved. 23. If an interim effluent limit established in this time schedule order for TDS, chloride, sodium, sulfate, or molybdenum is exceeded, then the Discharger is subject to a mandatory minimum penalty for that particular exceedance as the Discharger will no longer meet the exemption in Water Code section 13385, subdivision (j)(3). IT IS HEREBY ORDERED, pursuant to California Water Code sections 13300 and 13383 and to ensure compliance with the requirements of adopted Waste Discharge Requirements Order R3-2024-0001, NPDES Permit CA0049224: 1. The Discharger shall comply with the following schedule of actions: DRAFT TSO R3-2024-0021 -6- September 1, 2024 Table 2. Compliance Schedule for Total Dissolved Solids, Chloride, Sodium, Sulfate, Molybdenum (Starting September 1, 2024) Required Actions Compliance Due Dates Submit semi-annual progress and sampling results of TDS, chloride, sodium, sulfate, and molybdenum in Facility influent and effluent. Reports shall include but not be limited to: • Discussion of overall progress in implementing the requirements of this TSO and achieving full compliance with Order R3-2024-0001 • Results of source identification efforts and potential modifications to local limits or other pretreatment program actions • Evaluation of compliance with final effluent limitations • Update the Pollution Prevention Plan (PPP) section with descriptions of actions to be taken in the upcoming year beginning with the August 15, 2025 report and annually thereafter. 1st Semi-annual Report (Jan-Jun) – due by Feb 15 2nd Semi-annual Report (Jul-Dec) – due by Aug 15 Submit Pollution Prevention Plan (PPP) for TDS, chloride, sodium, sulfate, and molybdenum. Requirements for the PPP are set forth below. Submit an annual update to the PPP as a section in the semi-annual progress report describing planned actions for the upcoming year and discussing results from the previous year. PPP for calendar year 2025 due January 15, 2025 Updated PPP for 2026 due Aug 15, 2025 Updated PPP for 2027 due Aug 15, 2026 Updated PPP for 2028 due Aug 15, 2027 Updated PPP for 2029 due Aug 15, 2028 Submit Source Identification Study plan for review and approval by the Executive Officer. Requirements for the Source Identification Study are set forth below. January 15, 2025 Initiate Source Identification Study May 31, 2025 Submit Local Limits Study plan for review and approval by the Executive Officer. Requirements for the Local Limits Study are set forth below. May 1, 2026 Submit Source Identification Study results. Nov 1, 2026 Initiate Local Limits Study. Nov 1, 2026 DRAFT TSO R3-2024-0021 -7- September 1, 2024 Required Actions Compliance Due Dates Submit draft Local Limits Study report, including proposed changes to local limits. Nov 1, 2027 Submit final Local Limits Study report. May 1, 2028 Achieve full compliance with final effluent limitations in Order R3-2024-0001. August 31, 2029 Pollution Prevention Plan (PPP): The PPP is an iterative plan that the Discharger will update and submit on an annual basis. The annual PPP must include the following deliverables: a. A description of new or modified methods that will be used to prevent or reduce the amount of TDS, chloride, sodium, sulfate, and molybdenum in the facility's influent and effluent during the upcoming year. Pollution prevention methods may include application and enforcement of local limits to industrial or commercial dischargers, public education and outreach, upgrades or changes to the Facility’s treatment system, or other innovative and alternative approaches to reduce discharges of TDS, chloride, sodium, sulfate, and molybdenum to and from the facility. b. An estimate of load reductions that may be attained through the methods identified above. c. A plan for monitoring and assessing the results of the pollution prevention plan. d. A discussion of the pollution prevention methods used during the previous year. e. An estimate of the load reductions that were attained during the previous year. f. Once completed, a summary of the findings of the Source Identification Study, including the monitoring results and all identified sources of TDS, chloride, sodium, sulfate, and molybdenum to and from the Facility. g. Once completed, a discussion of the findings of the Local Limits Study and a description of how the Facility’s pretreatment program will be modified. Source Identification Study: The Source Identification Study must, at a minimum, include a sampling plan consistent with the guidance in Chapter 4 of EPA’s Local Limits Development Guidance.1 The sampling must occur for a minimum of one year and must be carried out in such a manner that it is spatially and temporally representative. The Source Identification Study may include additional source identification or monitoring that the Discharger identifies as being useful in understanding and reducing all sources of pollutants in the Facility’s influent and effluent. Local Limits Study: The Local Limits Study must include a detailed re-evaluation of local limits, as described in EPA’s Local Limits Development Guidance. The Local Limits Study will use the results of the Source Identification Study to calculate or recalculate maximum allowable headworks loadings (MAHLs) for TDS, chloride, 1 https://www3.epa.gov/npdes/pubs/final_local_limits_guidance.pdf DRAFT TSO R3-2024-0021 -8- September 1, 2024 sodium, sulfate, molybdenum, and any other pollutants identified as requiring further evaluation. The Discharger must use the MAHLs to develop or update local limits. 2. If the Discharger is unable to perform any activity or submit any documentation in compliance with the deadlines set forth in Table 2, the Discharger may request, in writing, an extension of the time. The extension request shall include justification for the delay and shall be submitted at least thirty days prior to the respective deadline to be considered complete and timely. 3. The following interim effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum shall be effective upon issuance of this time schedule order and shall apply in lieu of all final effluent limitations for those pollutants in Order R3-2024-0001. The Discharger shall maintain compliance with the following interim effluent limitations through August 31, 2029, or until the Discharger is able to come into compliance with the final effluent limitations, whichever is sooner. Table 3: Interim effluent limitations 1Compliance is determined using a 12-month running mean. 4. All reports shall be submitted under Discharger signed/certified cover letter to the California Integrated Water Quality System (CIWQS). The Executive Officer may require revisions to the form or types of data and information reported. 5. All reports required by this time schedule order shall be signed by either a principal executive officer or ranking elected official, or by a duly authorized representative of that person. A person is a duly authorized representative only if: a. The authorization is made in writing by a person described above; b. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the owner of the regulated facility. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.); and c. The written authorization is submitted to the Central Coast Water Board. 6. Any person signing a report required by this time schedule order shall make the following certification: “I certify under penalty of perjury that this document and all attachments were prepared by me, or under my direction or supervision, following a system designed to ensure that qualified personnel properly gather and evaluate the information submitted. To the best of my knowledge and belief, this document and all attachments are true, accurate, and complete. I am aware that there are significant Parameter Units Average Annual1 Average Monthly TDS mg/L 988 Chloride mg/L 196 Sodium mg/L 196 Sulfate mg/L 157 Molybdenum mg/L 0.024 DRAFT TSO R3-2024-0021 -9- September 1, 2024 penalties for submitting false information, including the possibility of fine and imprisonment.” 7. If, in the opinion of the Executive Officer, the Discharger fails to comply with any provisions of this time schedule order or fails to consistently demonstrate substantive progress towards achieving full compliance with effluent limitations in Order R3-2024- 0001, the Executive Officer may terminate this time schedule order. In that case, or if compliance with the final effluent limitations for TDS, chloride, sodium, sulfate, or molybdenum in Order R3-2024-0001 is not achieved by the full compliance dates shown above in Table 2 or the Discharger has not received an extension according to Provision 2 above, the Discharger will not be exempt from the mandatory minimum penalties for violation of those effluent limitations and may also be subject to issuance of a cease and desist order in accordance with Water Code section 13301. The Central Coast Water Board reserves its right to take any enforcement action authorized by law. 8. During the effective period of this time schedule order, the Discharger shall comply with all provisions of Order R3-2024-0001, as renewed or revised, that are not in conflict with this time schedule order. If, in the opinion of the Executive Officer, the Discharger fails to comply with the provisions of this order, the Executive Officer may refer this matter to the Attorney General for judicial enforcement, may issue a complaint for administrative civil liability, or may take other enforcement actions. Failure to comply with this order may result in the assessment of administrative civil liability of up to $10,000 per violation, per day, depending on the violation, pursuant to the Water Code, including sections 13350 and 13385. The Central Coast Water Board reserves its right to take any enforcement actions authorized by law. Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Resources Control Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Resources Control Board must receive the petition by 5:00 p.m., 30 days after the date of the order, except that if the thirtieth day following the date of the order falls on a Saturday, Sunday, or state holiday, the petition must be received by 5:00 p.m. on the next business day. Copies of the law and regulations applicable to filing petitions may be found on the internet at: http://www.waterboards.ca.gov/public_notices/petitions/water_quality, or will be provided upon request. This Order is effective on [placeholder for TSO effective date]. The Executive Officer may modify the time schedule in this order to permit a specified task or tasks to be completed at later dates if the Discharger demonstrates and the Executive Officer determines that the delay was beyond the reasonable control of the Discharger to avoid. ORDERED BY ___ Ryan E. Lodge, Executive Officer DRAFT TSO R3-2024-0021 -10- September 1, 2024 R:\RB3\Shared\NPDES\Facilities\San Luis Obispo\San Luis Obispo\TSO R3-2024- 0021\Draft TSO\draft_tso_slo_R3-2024-0021.docx Place ID: 255380 CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101, San Luis Obispo, California 93401 Phone (805) 549-3147 Fax (805) 543-0397 Central Coast Regional Water Quality Control Board (http://www.waterboards.ca.gov/centralcoast) DRAFT ORDER R3-2024-0001 NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT NUMBER CA0049224 WASTE DISCHARGE REQUIREMENTS FOR THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY The following Discharger is subject to waste discharge requirements set forth in this Order: Discharger City of San Luis Obispo Name of Facility Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Table 1. Discharge Location Discharge Point Effluent Description Discharge Point Latitude (North) Discharge Point Longitude (West) Receiving Water 001 Tertiary treated domestic wastewater 35.244307° -120.680618° San Luis Obispo Creek 002 Disinfected Tertiary Recycled Municipal Wastewater - - Reclamation Use This Order was adopted on: April 18-19, 2024 This Order shall become effective on: July 1, 2024 This Order shall expire on: June 30, 2029 The Discharger shall file a Report of Waste Discharge as an application for reissuance of waste discharge requirements in accordance with title 23, California Code of Regulations and an application for reissuance of a National Pollutant Discharge CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 2 Elimination System permit no later than 180 days prior to the Order expiration date. The U.S. Environmental Protection Agency and the California Regional Water Quality Control Board, Central Coast Region have classified this discharge as follows: Major discharge. I, Ryan E. Lodge, Executive Officer, do hereby certify that this Order with all attachments is a full, true, and correct copy of an order adopted by the California Regional Water Quality Control Board, Central Coast Region on the date indicated above. Ryan E. Lodge, Executive Officer CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 3 TABLE OF CONTENTS 1. FACILITY INFORMATION .......................................................................................... 4 2. FINDINGS ................................................................................................................... 4 3. DISCHARGE PROHIBITIONS .................................................................................... 7 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS ................................. 7 4.1. Effluent Limitations – Discharge Point 001 ........................................................ 7 4.2. Land Discharge Specifications – Not Applicable ............................................. 11 4.3. Recycling Specifications – Discharge Point 002 ............................................. 11 5. RECEIVING WATER LIMITATIONS ......................................................................... 12 5.1. Surface Water Limitations ............................................................................... 12 5.2. Groundwater Limitations ................................................................................. 16 6. PROVISIONS ............................................................................................................ 17 6.1. Standard Provisions ........................................................................................ 17 6.2. Monitoring and Reporting Program (MRP) Requirements ............................... 17 6.3. Special Provisions ........................................................................................... 17 7. COMPLIANCE DETERMINATION ............................................................................ 23 TABLE OF TABLES Table 1. Discharge Location ............................................................................................ 1 Table 2. Effluent Limitations at Discharge Point 001 ....................................................... 7 Table 3. Organic Substances Water Quality Criteria ..................................................... 14 Table 4. Hardness Dependent Metals Criteria .............................................................. 15 Table 5. Annual Mean Surface Water Quality Objectives .............................................. 15 Table 6. Groundwater Objectives .................................................................................. 17 TABLE OF ATTACHMENTS ATTACHMENT A – DEFINITIONS ...............................................................................A-1 ATTACHMENT B – MAP ..............................................................................................B-1 ATTACHMENT C – FLOW SCHEMATIC .................................................................... C-1 ATTACHMENT D – STANDARD PROVISIONS ......................................................... D-1 ATTACHMENT E – MONITORING AND REPORTING PROGRAM ............................E-1 ATTACHMENT F – FACT SHEET ............................................................................... F-1 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 4 1. FACILITY INFORMATION Information describing the City of San Luis Obispo (Discharger) Water Resource Recovery Facility (Facility) is summarized on the cover page and in sections 1 and 2 of the Fact Sheet (Attachment F). Section 1 of the Fact Sheet also includes information regarding the Facility’s permit application. 2. FINDINGS The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 2.1. Legal Authorities. This Order serves as waste discharge requirements (WDRs) pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA) and implementing regulations adopted by the United States Environmental Protection Agency (U.S. EPA) and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as a National Pollutant Discharge Elimination System (NPDES) permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1 subject to the WDRs in this Order. 2.2. Background and Rationale for Requirements. The Central Coast Water Board developed the requirements in this Order based on information submitted as part of the application, through monitoring and reporting programs, and other available information. The Fact Sheet (Attachment F), which contains background information and rationale for the requirements in this Order, is hereby incorporated into and constitutes Findings for this Order. Attachments A through E are also incorporated into this Order. 2.3. Provisions and Requirements Implementing State Law. Some provisions/requirements in this Order are included to implement state law only. These provisions/requirements are not required or authorized under the federal CWA; consequently, violations of these provisions/requirements are not subject to the enforcement remedies that are available for NPDES violations. 2.4. Water Reclamation Requirements for Recycled Water Production and Use. This Order allows the production and use of disinfected secondary and tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements established by the California Department of Public Health in title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. Additionally, this Order includes water reclamation requirements for the Facility pursuant to the State Water Resources Control Board’s (State Water Board’s) Division of Drinking Water (DDW) recommendations submitted to the Central Coast Water Board. The distribution and offsite reuse of recycled water produced by the Facility is subject to the State Water Board’s General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW), or other applicable permit, dependent on final use. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 5 2.5. Response to Climate Change. Climate change refers to observed changes in regional weather patterns such as temperature, precipitation, and storm frequency and size. At the local scale, within urbanized areas, climate change may directly impact groundwater and surface water supply; drainage, flooding, and erosion patterns; and ecosystems and habitat. This shift in climate, combined with California’s growing population, has increased reliance on pumping, conveying, treating, and heating water, increasing the water sector’s greenhouse gas emissions. The State Water Board’s Resolution 2017-0012, Comprehensive Response to Climate Change, requires a proactive response to climate change in all California Water Board actions, with the intent to embed climate change consideration into all programs and activities. Aligning with Resolution 2017-0012, this Order supports the beneficial reuse of the Facility’s treated effluent to offset potable water supplies for irrigation and dedicated in-stream flows to support critical creek habitat. This Order incorporates requirements for the Facility to beneficially reuse treated effluent, which serves to diversify the State’s water supply portfolio to prepare for uncertainties in water resources due to the changing climate through ongoing implementation, monitoring, and updating of the Discharger’s climate action planning efforts using the best available data and technology for wastewater treatment and operation. In 2019, the City participated in the development of the Multi-Jurisdictional San Luis Obispo Hazard Mitigation, a planning effort that identifies and prioritizes the City’s vulnerability to hazards and outlines mitigation goals and objectives. In August 2020, the City adopted its Climate Action Plan with goals for community-wide carbon neutrality by 2035. Most recently, on January 17, 2023, The City adopted the Climate Adaptation and Safety Element as part of its general plan. According to Disaster Mitigation Act (DMA) requirement §201.6(d)(3), the City must review and revise this plan within five years for continued mitigation project grant funding. Additionally, the City is currently undergoing construction of the SLO Water Plus project, which includes Facility upgrades to improve the Facility’s energy efficiency, provide flood protection improvements, increase treatment capacity, and improve resource recovery. To incorporate proactive planning for the future, this Order requires the Discharger to report on implementation progress, monitoring, and planning updates at this Facility as it relates to flooding, wildfire, renewable energy generation and energy efficiency, temperature, water recycling, biosolids reuse, and influent flow and loading fluctuations exacerbated by climate change. 2.6. Human Right to Water. California Water Code section 106.3 established the policy that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. On January 26, 2017, the Central Coast Water Board adopted Resolution R3-2017- 0004, which adopts the human right to water as a core value and affirms the realization of the human right to water and protecting human health as the Central Coast Water Board's top priorities. Consistent with the human right to water stated in California Water Code section 106.3, subdivision (a), and the Central Coast Water Board’s Resolution R3-2017-0004, this Order promotes actions that advance the human right to water and discourages actions that delay or impede opportunities for communities to secure safe, clean, affordable, and accessible CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 6 water adequate for human consumption, cooking, and sanitary purposes. This Order implements recently updated mercury water quality objectives that are more stringent than previous objectives to more adequately protect beneficial uses related to water and fish consumption. 2.7. Disadvantaged Community Status. Environmental Justice principles call for the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income in the development, adoption, implementation, and enforcement of all environmental laws, regulations, and policies that affect every community’s natural resources and the places people live, work, play, and learn. The Central Coast Water Board implements regulatory activities and water quality projects in a manner that ensures the fair treatment of all people, including Underrepresented Communities. Underrepresented Communities include but are not limited to Disadvantaged Communities (DACs), Severely Disadvantaged Communities (SDACs), Economically Distressed Areas (EDAs), Tribes, Environmentally Disadvantaged Communities (EnvDACs), and members of Fringe Communities.1 Furthermore, the Central Coast Water Board is committed to providing all stakeholders the opportunity to participate in the public process and provide meaningful input to decisions that affect communities. To meet environmental justice principles, staff has evaluated the disadvantaged community status for the Discharger. Using 2020 census data, the California Department of Water Resources Disadvantaged Community (DAC) Mapping Tool 1 identifies 16 block groups in the City of San Luis Obispo, representing approximately 54 percent of the population, as disadvantaged communities. The tool defines a DAC as a census block with a median household income between $50,458 and $67,278 and a severely disadvantaged community (SDAC) as a census block with a median household income below $50,458. The SDAC census blocks in the City of San Luis Obispo have median household incomes of $8,075, $9,596, $11,935, $28,173, $28,284, $35,774, $39,526, and $44,167. The DAC census blocks in the City of San Luis Obispo have median household income of $51,074, $52,961, $55,769, $56,866, $57,175, $57,803, $58,083, and $60,417. 2.8. Notification of Interested Persons. The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provided them with an opportunity to submit their written comments and recommendations. Details of the notification are provided in the Fact Sheet, Attachment F. 2.9. Consideration of Public Comment. The Central Coast Water Board, in a public meeting, heard and considered all comments pertaining to the discharge. Details of the public hearing are provided in the Fact Sheet, Attachment F. THEREFORE, IT IS HEREBY ORDERED that this Order supersedes Order R3-2014- 0033, except for enforcement purposes, that Waste Discharge/Master Reclamation 1 The DAC Mapping Tool is used to inform statewide Integrated Water Resources Management (IRWM), Sustainable Groundwater Monitoring Act (SGMA), and California Water Plan implementation efforts and can be found at the following website: https://gis.water.ca.gov/app/dacs/. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 7 Requirements Order R3-2003-081 is terminated upon Discharger’s enrollment in State Water Board Order WQ-2016-0068-DDW, except for enforcement purposes, and, in order to meet the provisions contained in division 7 of the California Water Code (commencing with section 13000) and regulations adopted thereunder and the provisions of the CWA and regulations and guidelines adopted thereunder, the Discharger shall comply with the requirements in this Order. This action in no way prevents the Central Coast Water Board from taking enforcement action for violations of the previous orders. 3. DISCHARGE PROHIBITIONS 3.1. Discharge of treated wastewater at a location or in a manner other than as described by this Order at Discharge Points 001 and 002, with compliance measured at EFF-001 and EFF-002 respectively as described in the Monitoring and Reporting Program (MRP) Attachment E, is prohibited. 3.2. The discharge of any waste not specifically regulated by this Order, excluding stormwater regulated by General Permit CAS000001 (Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities), is prohibited. 3.3. The overflow or bypass of wastewater from the Discharger’s collection, treatment, or disposal facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7 (Bypass), is prohibited. 3.4. Creation of a condition of pollution, contamination, or nuisance, as defined by section 13050 of the California Water Code, is prohibited. 3.5. The discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat. 3.6. The discharge of radioactive substances is prohibited. 3.7. The average dry weather daily discharge flow shall not exceed 5.4 million gallons per day (MGD). 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS 4.1. Effluent Limitations – Discharge Point 001 4.1.1. Final Effluent Limitations – Discharge Point 001 4.1.1.1. The Discharger shall maintain compliance with the following effluent limitations at Discharge Point 001, with compliance measured at Monitoring Location EFF- 001A or EFF-001B as described in the Monitoring and Reporting Program (MRP), Attachment E. Table 2. Effluent Limitations at Discharge Point 001 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 8 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1,351 2,252 - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - TSS lbs/day[1] 425 1,351 3,378 - - - pH[2],[3] standard units - - - 7.0 8.3 - Oil and Grease mg/L 5 - 10 - - - Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - Dissolved Oxygen mg/L - - - 4.0 - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.012 - 0.024 - - - Chlorodibromomethane (Dibromochloromethane) µg/L 0.40 - 0.81 - - - Chloroform µg/L 60 - 120.6 - - - Dichlorobromomethane µg/L 0.56 - 0.96 - - - CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 9 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Methylene Chloride µg/L 4.7 - 9.45 - - - Pentachlorophenol µg/L 0.28 - 0.56 - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - Nitrite, Total mg/L 1 - - - - - Un-ionized Ammonia mg/L 0.025 - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - Molybdenum mg/L 0.01 - - - - - Total Dissolved Solids mg/L 650 - - - - - Chloride mg/L 100 - - - - - Sodium mg/L 50 - - - - - Sulfate mg/L 100 -- - - - - Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail ” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 10 [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 7.0-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 7.0-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0-9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 7.0-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30- day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in-stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP-Attachment E). 4.1.1.2. Percent Removal: The average monthly percent removal of BOD 5-day at 20°C and total suspended solids shall not be less than 85 percent. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 11 4.1.1.3. Floating Material: Discharge of treated wastewater through Discharge Point 001 shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 4.1.2. Interim Effluent Limitations – Not Applicable 4.2. Land Discharge Specifications – Not Applicable 4.3. Recycling Specifications – Discharge Point 002 As specified below, this Order conditionally authorizes the Discharger to act as the producer of recycled (or reclaimed) water and to reuse recycled water onsite at the Facility and for other purposes. The Discharger is responsible for compliance with all applicable requirements associated with the production and onsite use of recycled water as specified within this Order. The Discharger filed a California Code of Regulations title 22 engineering report on August 14, 2020, that described recycled water quality produced at the Facility as "disinfected tertiary" (as defined in title 22, section 60301.230) and submitted a Notice of Intent (NOI) on August 14, 2020, to enroll under the State Water Board General Water Reclamation Requirements for Recycled Water Use (Order WQ 2016-0068-DDW). The distribution and offsite reuse of recycled water produced by the Facility are subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. Order WQ 2016-0068-DDW supersedes Waste Discharge/Master Reclamation Requirements Order R3-2003-081. 4.3.1. Reclamation and use of treated wastewater shall adhere to applicable requirements of California Water Code sections 13500-13577 (Water Reclamation) and California Code of Regulations, title 17 sections 7583-7586, title 17 sections 7601-7605, and title 22 sections 60301-60355 (Uniform Statewide Recycling Criteria). 4.3.2. Recycled water production shall comply with a title 22 engineering report approved by DDW that demonstrates or defines compliance with the Uniform Statewide Recycling Criteria. 4.3.3. Recycled water shall be disinfected tertiary recycled water, as defined by California Code of Regulations title 22, section 60301.230. 4.3.4. Recycled water shall be adequately oxidized, filtered, and disinfected, as defined in title 22. 4.3.5. Turbidity in tertiary recycled water shall not exceed any of the following limits: 4.3.5.1. An average of 0.2 NTU within a 24-hour period; and 4.3.5.2. 0.5 NTU at any time. 4.3.6. Total coliform bacteria measured in the disinfected recycled water shall not exceed the following limits: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 12 4.3.6.1. An MPN of 2.2 per 100 mL calculated as a median concentration utilizing the bacteriological results of the last seven days for which analyses have been completed, 4.3.6.2. An MPN of 23 per 100 mL in more than one sample in any 30-day period, and 4.3.6.3. No sample shall exceed an MPN of 240 total coliform bacteria per 100 mL. 4.3.7. The Discharger shall discontinue delivery of recycled water to distributors and users during any period in which it has reason to believe that the limits established in this Order are not being met. The delivery of recycled water shall not be resumed until all conditions that caused the limits to be violated have been corrected. 4.3.8. Recycled water shall not exceed any maximum contaminant level established pursuant to sections 116275(c)(1) and (d) of the California Health and Safety Code or established by the U.S. EPA. 4.3.9. Recycled water disinfected with chlorine shall have a chlorine concentration time modal contact time (CT) value of not less than 450 mg-min/L at all times with a modal contact time of at least 90 minutes based on peak dry weather design flow. 4.3.10 If a disinfection method other than chlorine is used, the disinfection process shall be a process that, when combined with the filtration process, has been demonstrated to inactivate and/or remove 99.999 percent of the plaque forming units of F-specific bacteriophage MS2, or polio virus in the wastewater. A virus that is at least as resistant to disinfection as polio virus may be used for purposes of the demonstration. 4.3.11. The Discharger shall adhere to the manufacturer’s recommended operating conditions for the ultraviolet (UV) system. 4.3.12. Personnel involved in producing, transporting, or using recycled water shall be informed of possible health hazards that may result from contact and use of recycled water. 4.3.13. All areas where recycled water is in use and with public access shall be posted with signs in English and an international symbol to warn the public that recycled wastewater is being stored or used. 4.3.14. Recycled water systems at the Facility shall be properly labeled and regularly inspected to ensure proper operation, absence of leaks, and absence of illegal connections. 5. RECEIVING WATER LIMITATIONS 5.1. Surface Water Limitations Receiving water limitations are based on water quality objectives contained in the Water Quality Control Plan for the Central Coastal Basin (Basin Plan) and are a required part of this Order. The discharge shall not cause a violation of the following receiving water limitations in San Luis Obispo Creek. The discharge from the wastewater treatment facility shall comply with the following in the receiving waters: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 13 5.1.1. Waters shall be free of coloration that causes nuisance or adversely affects beneficial uses. Coloration attributable to materials of waste origin shall not be greater than 15 units or 10 percent above natural background color, whichever is greater. 5.1.2. Waters shall not contain taste or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, that cause nuisance, or that adversely affect beneficial uses. 5.1.3. Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.4. Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.5. Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. 5.1.6. Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. 5.1.7. Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses. 5.1.8. The suspended sediment load and suspended sediment discharge rate to surface waters shall not be altered in such a manner as to cause nuisance or adversely affect beneficial uses. 5.1.9 Concentrations of toxic metals and inorganic chemicals in waters shall not be increased in such a manner that may adversely affect beneficial uses. 5.1.10. Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Increase in turbidity attributable to controllable water quality factors shall not exceed the following limits. 5.1.10.1. Where natural turbidity is between 0 and 50 NTUs, increases shall not exceed 20 percent. 5.1.10.2. Where natural turbidity is between 50 and 100 NTUs, increases shall not exceed 10 NTU. 5.1.10.3. Where natural turbidity is greater than 100 NTUs, increases shall not exceed 10 percent. 5.1.11. The pH value shall not be depressed below 7.0 nor raised above 8.3. The change in normal ambient pH levels shall not exceed 0.5 units. 5.1.12. Dissolved oxygen concentrations in receiving waters shall not be reduced below 7.0 mg/L at any time. 5.1.13. Discharged effluent shall not cause the receiving water temperature to increase more than 5° Fahrenheit (F) above the receiving water temperature. If, due to CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 14 the Creek’s low temperature as determined by early-morning monitoring, the discharge causes the Creek’s temperature to exceed the limit, the Discharger must ensure the discharge shall not cause the receiving water to exceed 72.5° F (22.5° C). The discharger shall monitor the Creek again four hours after discovering the exceedance and shall report both results to the Executive Officer in the monthly self-monitoring report. 5.1.14. All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge. 5.1.15. The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/L (as N) in the receiving water. 5.1.16. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect the beneficial uses of the receiving water. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life. For waters where existing concentrations are presently nondetectable or where beneficial uses would be impaired by concentrations in excess of nondetectable levels, total identifiable chlorinated hydrocarbon pesticides shall not be present at concentrations detectable within the accuracy of analytical methods as prescribed in Standard Methods for the Examination of Water and Wastewater, latest edition, or other equivalent methods approved by the Executive Officer. 5.1.17. Waters shall not contain organic substances in concentrations greater than those listed in the table below: Table 3. Organic Substances Water Quality Criteria Parameter Units Water Quality Objective Methylene Blue Activated Substances mg/L 0.2 Phenols ug/L 1.0 Polychlorinated Biphenyls (PCBs) [1] µg/L 0.3 Phthalate Esters µg/L 0.002 [1] PCBs refer to sum of PCB 1016, 1221, 1232, 1242, 1248, 1254, and 1260. 5.1.18. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstance shall receiving waters contain concentrations of radionuclides in excess of the maximum contaminant levels (MCLs) for radioactivity presented in title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.1.19. Receiving waters shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 15 Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.1.20. Receiving waters shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural beneficial use. Interpretation of adverse effects shall be derived from the University of California Agricultural Extension Service guidelines presented in section 3, Table 3-1 of the 2019 Basin Plan. 5.1.21. Receiving waters shall not contain concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in section 3, Table 3-2 of the Basin Plan. Salt concentrations for irrigations waters shall be controlled through implementation of the anti-degradation policy to the effect that mineral constituents of currently or potentially usable waters shall not be increased. 5.1.22. Receiving waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife in excess of the levels presented in section 3, Table 3-3 of the 2019 Basin Plan. The concentrations of metals listed in the table below shall not be exceeded for the protection of aquatic life. Table 4. Hardness Dependent Metals Criteria Parameter Units Receiving Water Hardness >100 mg/L calcium carbonate (CaCO3) Receiving Water Hardness <100 mg/L CaCO3 Cadmium mg/L 0.003 0.0004 Chromium mg/L 0.05 0.05 Copper mg/L 0.03 0.01 Lead mg/L 0.03 0.03 Mercury mg/L 0.0002 0.0002 Nickel mg/L 0.4 0.1 Zinc mg/L 0.2 0.004 5.1.23. E. coli concentrations shall not exceed 100 MPN/100 mL as a 6-week rolling geometric mean, calculated weekly. A statistical threshold value (STV) of 320 MPN/100 mL for E. coli shall not be exceeded by more than 10 percent of samples collected in a calendar month, calculated in a static manner. 5.1.24. Discharges shall not cause receiving water to exceed the water quality objectives for the Estero Bay Hydrologic Unit (San Luis Obispo Creek Sub-Area) specifically identified by Table 3-5 of the 2019 Basin Plan, as shown in the table below. Objectives shown are annual mean values. Objectives are based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 5. Annual Mean Surface Water Quality Objectives CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 16 Parameter Units Annual Mean Total Dissolved Solids mg/L 650 Chloride mg/L 100 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 5.2. Groundwater Limitations Activities at the Facility shall not cause exceedance/deviation from the following water quality objectives for groundwater established by the 2019 Basin Plan. The Central Coast Water Board may require the Discharger to investigate the cause of exceedances in the groundwater before determining whether the Discharger caused any water condition that exceeds the following groundwater limitations. 5.2.1. Groundwater shall not contain taste or odor-producing substances in concentrations that adversely affect beneficial uses. 5.2.2. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstances shall groundwater contain concentrations of radionuclides in excess of the MCLs for radioactivity presented in Title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.2.3. The Discharger shall not cause a statistically significant increase of mineral constituent concentrations in underlying groundwater as determined by comparison of samples collected from wells located up-gradient and down- gradient of the waters affected by the discharge. 5.2.4. The median concentration of coliform organisms in groundwater, over any seven- day period, shall be less than 2.2 organisms per 100 mL. 5.2.5. Groundwater shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.2.6. Groundwater shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural supply beneficial use. Interpretation of adverse effects shall be as derived in University of California Agricultural Extension Service guidelines provided in Table 3-1 of the 2019 Basin Plan. 5.2.7. Groundwater used for irrigation and livestock watering shall not exceed concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in chapter 3, Table 3-2 of the 2019 Basin Plan. 5.2.8. Groundwater shall not contain constituents greater than the following concentrations established in Table 3-6 of the 2019 Basin Plan for groundwaters within the San Luis Obispo Creek sub-area (Estero Bay sub-basin). Objectives CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 17 shown are annual median values. Objectives based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 6. Groundwater Objectives Parameter Units Annual Median TDS mg/L 900 Chloride mg/L 200 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 Nitrogen mg/L 5 6. PROVISIONS 6.1. Standard Provisions 6.1.1. The Discharger shall comply with all Standard Provisions included in Attachment D. 6.1.2. The Discharger shall comply with Central Coast Water Board Standard Provisions in Attachment D. In the event that there is any conflict, duplication, or overlap between provisions specified by this Order, the more stringent provision shall apply. 6.2. Monitoring and Reporting Program (MRP) Requirements The Discharger shall comply with the MRP, and future revisions thereto, in Attachment E. 6.3. Special Provisions 6.3.1. Reopener Provisions 6.3.1.1. This Order may be reopened for modification, or revocation and reissuance, as a result of the detection of a reportable priority pollutant generated by special conditions included in this Order. These special conditions may be, but are not limited to, fish tissue sampling, whole effluent toxicity, monitoring requirements on internal waste stream(s), monitoring for surrogate parameters, and other new information. Additional requirements may be included in this Order as a result of the special condition monitoring data. 6.3.1.2. This Order may be reopened and modified in accordance with NPDES regulations at 40 Code of Federal Regulations (CFR) parts 122 and 124, as necessary, to include additional conditions or limitations based on newly available information or to implement any U.S. EPA approved, new, state water quality objective. 6.3.1.3. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 18 to cause, or contributes to an excursion above a State Implementation Policy (SIP) water quality objective. 6.3.1.4. This Order may be reopened and modified to revise the most sensitive species to be used for acute and/or chronic aquatic toxicity testing once the required species sensitivity is completed in accordance with section 5 of the MRP (Attachment E). Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. 6.3.1.5 This Order may be reopened and modified to reevaluate reasonable potential for acute toxicity, and establish acute toxicity effluent limitations, if warranted, after the evaluation of new data and information. 6.3.2. Special Studies, Technical Papers and Additional Monitoring Requirements 6.3.2.1. Toxicity Reduction Requirements For compliance with the Basin Plan’s narrative toxicity objective, this Order requires the Discharger to conduct acute and chronic whole effluent toxicity (WET) testing, as specified in section 5 of the MRP. Furthermore, this Provision requires the Discharger to investigate the causes of and identify corrective actions to reduce or eliminate effluent toxicity. If the discharge exceeds the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring established in this Provision, the Discharger is required to initiate a Toxicity Reduction Evaluation (TRE) in accordance with an approved TRE Work Plan and take actions to mitigate the impact of the discharge and prevent recurrence of toxicity. A TRE is a site-specific study conducted in a stepwise process to identify the source(s) of toxicity and the effective control measures for effluent toxicity. TREs are designed to identify the causative agents and sources of whole effluent toxicity, evaluate the effectiveness of the toxicity control options, and confirm the reduction in effluent toxicity. This Provision includes requirements for the Discharger to update and submit their TRE Work Plan and includes procedures for accelerated toxicity monitoring and TRE initiation: 6.3.2.1.1. TRE Work Plan. Within 90 days of the effective date of this Order, the Discharger shall submit to the Central Coast Water Board an updated TRE Work Plan for approval by the Executive Officer. The TRE Work Plan shall outline the procedures for identifying the source(s) of and reducing or eliminating effluent toxicity. The TRE Work Plan must be developed in accordance with U.S. EPA guidance and be of adequate detail to allow the Discharger to immediately initiate a TRE as required in this Provision. 6.3.2.1.2. Accelerated Monitoring and TRE Initiation. When the numeric toxicity monitoring trigger or effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all test acceptability criteria (TAC), the Discharger shall initiate accelerated monitoring as required in the Accelerated Monitoring Specifications in section 5 of the MRP. The Discharger shall initiate a TRE to address effluent toxicity if any WET testing results exceed CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 19 the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring. 6.3.3. Best Management Practices and Pollution Prevention 6.3.3.1. Salt and Nutrient Management Program 6.3.3.1.1 The Discharger shall continue to update and implement an ongoing Salt Management Program, with the intent of reducing mass loading of salts in treated effluent and attainment of applicable water quality objectives for salts in the San Luis Obispo Creek Sub-Basin Area of the Estero Bay Drainage Basin. Additionally, the Discharger shall continue to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable water quality objectives for nutrients in the same basin. 6.3.3.1.2 Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. 6.3.3.1.3 Nutrient reduction measures shall focus on optimizing wastewater treatment processes for nitrification and denitrification, or other means of nitrogen removal. Reduction measures may also include source control (non-human waste from commercial and industrial sources) as appropriate. 6.3.3.1.4 As part of the Salt and Nutrient Management Program, the Discharger shall submit an annual report describing salt and nutrient reduction efforts as described in the section 9.3 of the MRP (Attachment E). 6.3.3.1.5 As an alternative to the Salt and Nutrient Management Program requirements described above, upon Executive Officer approval, the Discharger may submit documentation and summary of participation in a regional salt/nutrient management plan implemented under the provisions of State Water Board Resolution No. 2018-0057 (Recycled Water Policy). 6.3.3.2. Pollutant Minimization Program 6.3.3.2.1.The Discharger shall develop and conduct a Pollutant Minimization Program (PMP) as further described below when there is evidence (e.g., sample results reported as detected not quantifiable (DNQ) when the effluent limitation is less than the MDL, sample results from analytical methods more sensitive than those methods required by this Order, presence of whole effluent toxicity, health advisories for fish consumption, results of benthic or aquatic organism tissue sampling) that a priority pollutant is present in the effluent above an effluent limitation and either: 6.3.3.2.1.1. A sample result is reported as DNQ and the effluent limitation is less than the reporting limit (RL); or 6.3.3.2.1.2. A sample result is reported as non-detect (ND) and the effluent limitation is less than the MDL, using definitions described in Attachment A and reporting protocols described in MRP section 10.2.4. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 20 6.3.3.2.2. The PMP shall include, but not be limited to, the following actions and submittals acceptable to the Central Coast Water Board Executive Officer: 6.3.3.2.2.1. An annual review and semi-annual monitoring of potential sources of the reportable priority pollutant(s), which may include fish tissue monitoring and other bio-uptake sampling; 6.3.3.2.2.2. Quarterly monitoring for the reportable priority pollutant(s) in the influent to the wastewater treatment system; 6.3.3.2.2.3. Submittal of a control strategy designed to proceed toward the goal of maintaining concentrations of the reportable priority pollutant(s) in the effluent at or below the effluent limitation; 6.3.3.2.2.4. Implementation of appropriate cost-effective control measures for the reportable priority pollutant(s), consistent with the control strategy; and 6.3.3.1.2.5. An annual status report that shall be sent to the Central Coast Water Board including: 6.3.3.1.2.5.1. All PMP monitoring results for the previous year; 6.3.3.1.2.5.2. A list of potential sources of the reportable priority pollutant(s); 6.3.3.1.2.5.3. A summary of all actions undertaken pursuant to the control strategy; and 6.3.3.1.2.5.4. A description of actions to be taken in the following year. 6.3.4. Construction, Operation and Maintenance Specifications 6.3.4.1. The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.3.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.3.5.1. Biosolids. The handling, management, and disposal of sludge and solids derived from wastewater treatment must comply with applicable provisions of U.S. EPA regulations at 40 CFR sections 257, 258, 501, and 503, including all monitoring, record keeping, and reporting requirements. Solids and sludge treatment, storage, and disposal or reuse shall not create a nuisance, such as objectionable odors or flies, and shall not result in ground water contamination. Sites for solids and sludge treatment and storage shall have adequate facilities to divert surface water runoff from adjacent areas to protect the boundaries of such sites from erosion, and to prevent drainage from treatment and storage sites. The treatment, storage, disposal, or reuse of sewage sludge and solids shall not cause waste material to be in a position where it is, or can be, conveyed from the treatment and storage sites and deposited into waters of the State. The Discharger is responsible for assuring that all biosolids produced at its facility are used or disposed of in accordance with the above rules, regardless of whether the Discharger uses or disposes of the biosolids itself, or transfers them to another party for further treatment, use, or disposal. The Discharger is CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 21 responsible for informing subsequent preparers, appliers, and disposers of the requirements that they must adhere to these rules. 6.3.5.2. Pretreatment. The Discharger shall be responsible for the performance for all pretreatment requirements contained in 40 CFR part 403 and shall be subject to enforcement actions, penalties, fines, and other remedies by the U.S. EPA, or other appropriate parties, as provided in the CWA, as amended (33 USC 1351 et seq.). The Discharger shall implement and enforce its approved POTW Pretreatment Program. The Discharger’s approved POTW Pretreatment Program is hereby made an enforceable condition of this permit. U.S. EPA or the Central Coast Water Board may initiate enforcement action against an industrial user for noncompliance with applicable standards and requirements as provided in the CWA. The Discharger shall enforce the requirements promulgated under sections 307 (b), 307 (c), 307 (d), and 402 (b) of the CWA. The Discharger shall cause industrial users subject to Federal Categorical Standards to achieve compliance no later than the date specified in those requirements or, in the case of a new industrial user, upon commencement of the discharge. The Discharger shall perform the pretreatment functions as required in 40 CFR part 403, including, but not limited to the following: 6.3.5.2.1. Implement the necessary authorities as provided in 40 CFR section 403.8 (f) (1); 6.3.5.2.2. Enforce the pretreatment requirements under 40 CFR sections 403.5 and 403.6; 6.3.5.2.3. Implement the programmatic functions as provided in 40 CFR section 403.8 (f) (2); and 6.3.5.2.4. Provide the requisite funding and personnel to implement the pretreatment program as provided in 40 CFR section 403.8 (f) (3). 6.3.5.5. Resource Recovery from Anaerobically Digestible Material. If the Discharger will receive hauled-in anaerobically digestible material for injection into an anaerobic digester, the Discharger shall notify the Central Coast Water Board and develop and implement standard operating procedures for this activity. The standard operating procedures shall be developed prior to receiving hauled-in anaerobically digestible material. The standard operating procedures shall address material handling, including unloading, screening, or other processing prior to anaerobic digestion; transportation; spill prevention; and spill response. In addition, the standard operating procedures shall address avoidance of the introduction of materials that could cause interference, pass- through, or upset of the treatment processes; avoidance of prohibited material; vector control; odor control; operation and maintenance; and the disposition of any solid waste segregated from introduction to the digester. The Discharger shall train its staff on the standard operating procedures and shall maintain records for a minimum of five years for each load received, describing the hauler, waste type, and quantity received. In addition, the Discharger shall CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 22 maintain records for a minimum of five years for the disposition, location, and quantity of cumulative pre-digestion-segregated solid waste hauled offsite. 6.3.6. Other Special Provisions 6.3.6.1. Salt Management. Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. The Discharger shall assess additional pretreatment measures that may be taken to reduce influent salt concentrations and include a discussion of proposed and implemented measures in the annual report described below. The Discharger must also implement outreach to residential, commercial, and industrial salt contributors with the goal of reducing salts discharged to the collection system. 6.3.6.2. Discharges of Stormwater. For the control of stormwater discharged from the site of the wastewater treatment and disposal facilities, if applicable, the Discharger shall seek authorization to discharge under and meet the requirements of the State Water Board’s Water Quality Order 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.3.6.3. Statewide General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order No. 2022-0103-DWQ) The Discharger is subject to the requirements of and must separately comply with State Water Board Order 2022-0103-DWQ, Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems, including monitoring and reporting requirements, and any subsequent revision to that order. This General Permit, adopted on December 6, 2022, is applicable to all “federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California.” The purpose of the General Permit is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled under the General Permit. 6.3.6.4. Climate Change Adaptation Implementation Progress Report. On May 1, 2029, the Discharger shall submit a Climate Change Adaptation Implementation Progress Report 2 to the Central Coast Water Board Executive Officer describing the Discharger’s progress in implementing, monitoring, and updating its long-term approach for identifying and addressing climate change hazards and vulnerabilities at the Facility, including all associated infrastructure (e.g., treatment facilities, conveyances to discharge points, discharge facilities). 2 In place of a static document, the Discharger may develop a living document and/or set of tools that fulfills the components outlined for the Climate Change Adaptation Program. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 23 The Climate Change Adaptation Implementation Report shall, at a minimum, include the following components: 6.3.6.4.1. Climate Change Adaptation Implementation Status – Provide a status update on any city or county-wide reports that address Facility and or collection system climate change adaptation planning and or implantation. Submit copies of document(s) to CIWQS as attachments. 6.3.6.4.2. Resiliency Actions – Report progress on actions that build facility and operational resilience to identified vulnerabilities, accounting for options that minimize resource impacts. For the anticipated life of the facility, include an analysis of: • Precipitation pattern changes o Drought – Decreased influent quantity and quality o Peak Events – Flooding and increased influent quantity • Temperature fluctuations and extremes • Increased wildfires • Energy resilience o Energy efficiency o Renewable energy generation o Increased power outages • Biosolid reuse • Water recycling 6.3.6.4.3. Adaptation Strategy – Report progress and adjustments made to strategy to complete Resiliency Actions, encompassing the following: 6.3.6.4.3.1. Prioritization – How resiliency actions were prioritized based on risks to water quality, but also accounting for costs and benefits. 6.3.6.4.3.2. Schedule and Milestones – Ongoing and changing timeframes to complete prioritized resiliency actions and/or climate change hazard triggers to inform when the Discharger shall implement actions. Milestones to complete critical steps for prioritized Resiliency Actions, designed to demonstrate measurable progress at a steady, or accelerated, completion pace over the established timeframes. 6.3.6.4.3.3. Financial Planning – Costs of reported implementation and monitoring measures, projected costs necessary to continue implementation and monitoring of resiliency actions, and strategy to procure funds. 6.3.7. Compliance Schedules – Not Applicable 7. COMPLIANCE DETERMINATION 7.1. General Compliance with effluent limitations for reportable pollutants shall be determined using sample reporting protocols defined in the MRP and Attachment A of this Order. For purposes of reporting and administrative enforcement by the Central Coast and State Water Boards, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the reportable pollutant in the CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 24 monitoring sample is greater than the effluent limitation and greater than or equal to the reported Minimum Level (ML). 7.2. Chronic Toxicity The discharge is subject to determination of “Pass” or “Fail” from a chronic toxicity test using the Test of Significant Toxicity (TST) statistical t-test approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. The null hypothesis (Ho) for the TST statistical approach is: Mean discharge “in-stream” waste concentration (IWC) response ≤0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge (100 percent effluent) and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be reported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). 7.3. Multiple Sample Data When determining compliance with a measure of central tendency (arithmetic mean, geometric mean, median, etc.) of multiple samples analyses and the data set contains one or more reported determinations of DNQ, or ND, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 7.3.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 7.3.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 25 even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 7.4. Average Monthly Effluent Limitation (AMEL) If the average of daily discharges over a calendar month exceeds the AMEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that month for that parameter (e.g., resulting in 31 days of non-compliance in a 31-day month). The average of daily discharges over the calendar month that exceeds the AMEL for a parameter will be considered out of compliance for that month only. If only a single sample is taken during the calendar month and the analytical result for that sample exceeds the AMEL, the Discharger will be considered out of compliance for that calendar month. For any one calendar month during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar month. 7.5. Average Weekly Effluent Limitation (AWEL) If the average of daily discharges over a calendar week exceeds the AWEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that week for that parameter, resulting in seven days of non-compliance. The average of daily discharges over the calendar week that exceeds the AWEL for a parameter will be considered out of compliance for that week only. If only a single sample is taken during the calendar week and the analytical result for that sample exceeds the AWEL, the Discharger will be considered out of compliance for that calendar week. For any one calendar week during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar week. 7.6. Maximum Daily Effluent Limitation (MDEL) If a daily discharge exceeds the MDEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for that parameter for that one day only within the reporting period. For any one day during which no sample is taken, no compliance determination can be made for that day. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-1 A. ATTACHMENT A – DEFINITIONS Arithmetic Mean (μ) Also called the average, is the sum of measured values divided by the number of samples. For ambient water concentrations, the arithmetic mean is calculated as follows: where: Σx is the sum of the measured ambient water concentrations, and n is the number of samples. Average Monthly Effluent Limitation (AMEL) The highest allowable average of daily discharges over a calendar month, calculated as the sum of all daily discharges measured during a calendar month divided by the number of daily discharges measured during that month. Average Weekly Effluent Limitation (AWEL) The highest allowable average of daily discharges over a calendar week (Sunday through Saturday), calculated as the sum of all daily discharges measured during a calendar week divided by the number of daily discharges measured during that week. Bioaccumulative Those substances taken up by an organism from its surrounding medium through gill membranes, epithelial tissue, or from food and subsequently concentrated and retained in the body of the organism. Bioassay A test used to evaluate the relative potency of a chemical or a mixture of chemicals by comparing its effect on a living organism with the effect of a standard preparation on the same type of organism. Calendar Month(s) A period of time from a day of one month to the day before the corresponding day of the next month if the corresponding day exists, or if not to the last day of the next month (e.g., from January 1 to January 31, from June 15 to July 14, or from January 31 to February 28). Calendar Quarter A period of time defined as three consecutive calendar months. Calendar Year A period of time defined as twelve consecutive calendar months. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-2 Carcinogenic Pollutants are substances that are known to cause cancer in living organisms. Chronic Aquatic Toxicity Test A test to determine an adverse effect (sublethal or lethal) on a group of aquatic test organisms during an exposure of duration long enough to assess sub-lethal effects. Compliance with the effluent limitation for chronic toxicity in this Order is demonstrated by conducting chronic toxicity tests for the effluent as described in section 7.15 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E), and in accordance with the TST statistical approach. Coefficient of Variation (CV) CV is a measure of the data variability and is calculated as the estimated standard deviation divided by the arithmetic mean of the observed values. Continuous Dischargers Facilities that discharge without interruption throughout its operating hours, except for infrequent shutdowns for maintenance, process changes, or other similar activities, and that discharge throughout the calendar year. Daily Discharge Daily Discharge is defined as either: (1) the total mass of the constituent discharged over the calendar day (12:00 am through 11:59 pm) or any 24-hour period that reasonably represents a calendar day for purposes of sampling (as specified in the permit), for a constituent with limitations expressed in units of mass or; (2) the unweighted arithmetic mean measurement of the constituent over the day for a constituent with limitations expressed in other units of measurement (e.g., concentration). The daily discharge may be determined by the analytical results of a composite sample taken over the course of one day (a calendar day or other 24-hour period defined as a day) or by the arithmetic mean of analytical results from one or more grab samples taken over the course of the day. For composite sampling, if one day is defined as a 24-hour period other than a calendar day, the analytical result for the 24-hour period will be considered as the result for the calendar day in which the 24-hour period ends. Detected, but Not Quantified (DNQ) DNQ are those sample results less than the reporting limit (RL), but greater than or equal to the laboratory’s MDL. Sample results reported as DNQ are estimated concentrations. Dilution Credit Dilution Credit is the amount of dilution granted to a discharge in the calculation of a water quality-based effluent limitation, based on the allowance of a specified mixing zone. It is calculated from the dilution ratio or determined through conducting a mixing zone study or modeling of the discharge and receiving water. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-3 Dilution Ratio The critical low flow of the upstream receiving water divided by the flow of the effluent discharged. Effluent Concentration Allowance (ECA) ECA is a value derived from the water quality criterion/objective, dilution credit, and ambient background concentration that is used, in conjunction with the coefficient of variation for the effluent monitoring data, to calculate a long-term average (LTA) discharge concentration. The ECA has the same meaning as wasteload allocation (WLA) as used in United States Environmental Protection Agency (U.S. EPA) guidance (Technical Support Document for Water Quality-based Toxics Control, March 1991, second printing, EPA/505/2-90-001). Enclosed Bays Enclosed Bays means indentations along the coast that enclose an area of oceanic water within distinct headlands or harbor works. Enclosed bays include all bays where the narrowest distance between the headlands or outermost harbor works is less than 75 percent of the greatest dimension of the enclosed portion of the bay. Enclosed bays include, but are not limited to, Humboldt Bay, Bodega Harbor, Tomales Bay, Drake’s Estero, San Francisco Bay, Morro Bay, Los Angeles-Long Beach Harbor, Upper and Lower Newport Bay, Mission Bay, and San Diego Bay. Enclosed bays do not include inland surface waters or ocean waters. Estimated Chemical Concentration The estimated chemical concentration that results from the confirmed detection of the substance by the analytical method below the minimum level (ML) value. Estuaries and Coastal Lagoons Estuaries means waters, including coastal lagoons, located at the mouths of streams that serve as areas of mixing for fresh and ocean waters. Coastal lagoons and mouths of streams that are temporarily separated from the ocean by sandbars shall be considered estuaries. Estuarine waters shall be considered to extend from a bay or the open ocean to a point upstream where there is no significant mixing of fresh water and seawater. Estuarine waters included, but are not limited to, the Sacramento-San Joaquin Delta, as defined in California Water Code section 12220, Suisun Bay, Carquinez Strait downstream to the Carquinez Bridge, and appropriate areas of the Smith, Mad, Eel, Noyo, Russian, Klamath, San Diego, and Otay rivers. Estuaries do not include inland surface waters or ocean waters. Flow-Through Acute Toxicity Testing Systems A toxicity testing system where an effluent sample is either pumped continuously from the sampling point directly to a dilutor system, or collected and placed in a tank adjacent to the test laboratory and pumped continuously from the tank to a dilutor system. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-4 Inland Surface Waters All surface waters of the state that do not include the ocean, enclosed bays, or estuaries. Insignificant Dischargers National Pollutant Discharge Elimination System (NPDES) discharges that are determined to be a very low threat to water quality by the permitting authority. Instantaneous Maximum Effluent Limitation The highest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous maximum limitation). Instantaneous Minimum Effluent Limitation The lowest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous minimum limitation). In-stream Waste Concentration (IWC) The concentration of effluent in the receiving water after mixing as determined by the permitting authority. For purposes of aquatic toxicity testing for non-stormwater NPDES dischargers, the IWC shall be as described in section III.C.1 of the Toxicity Provisions. For assessing whether receiving waters meet the numeric water quality objectives (WQOs), the undiluted ambient water shall be used as the IWC in the TST as indicated in section III.B.3 of the Toxicity Provisions. Maximum Daily Effluent Limitation (MDEL) The highest allowable daily discharge of a pollutant, over a calendar day (or 24-hour period). For pollutants with limitations expressed in units of mass, the daily discharge is calculated as the total mass of the pollutant discharged over the day. For pollutants with limitations expressed in other units of measurement, the daily discharge is calculated as the arithmetic mean measurement of the pollutant over the day. For the purposes of chronic and acute aquatic toxicity, an MDEL is an effluent limitation based on the outcome of the TST approach and the resulting percent effect at the IWC, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Maximum Daily Effluent Target (MDET) For the purposes of chronic and acute aquatic toxicity, an MDET is a target used to determine whether a Toxicity Reduction Evaluation (TRE) should be conducted. Not meeting the MDET is not a violation of an effluent limitation. Median The middle measurement in a set of data. The median of a set of data is found by first arranging the measurements in order of magnitude (either increasing or decreasing order) If the number of measurements (n) is odd, then: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-5 If n is even, then: (i.e., the midpoint between the (n/2 and ((n/2)+1))). Median Monthly Effluent Limitation (MMEL) For the purposes of chronic and acute aquatic toxicity, an MMEL is an effluent limitation based on a maximum of three independent toxicity tests, analyzed using the TST, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Median Monthly Effluent Target (MMET) For the purposes of chronic and acute aquatic toxicity, an MMET is a target based on a maximum of three independent toxicity tests used to determine whether a TRE should be conducted. Not meeting the MMET is not a violation of an effluent limitation. Method Detection Limit (MDL) MDL is the minimum concentration of a substance that can be reported with 99 percent confidence that the measured concentration is distinguishable from method blank results, as defined in 40 Code of Federal Regulations (CFR) part 136, Attachment B. Minimum Level (ML) ML is the concentration at which the entire analytical system must give a recognizable signal and acceptable calibration point. The ML is the concentration in a sample that is equivalent to the concentration of the lowest calibration standard analyzed by a specific analytical procedure, assuming that all the method specified sample weights, volumes, and processing steps have been followed. Mixing Zone Mixing Zone is a limited volume of receiving water that is allocated for mixing with a wastewater discharge where water quality criteria can be exceeded without causing adverse effects to the overall water body. MMEL Compliance Tests For the purposes of chronic and acute aquatic toxicity, MMEL compliance tests are a maximum of two tests that are used in addition to the routine monitoring test to determine compliance with the chronic and acute aquatic toxicity MMEL and MDEL. MMET Tests For the purposes of chronic and acute aquatic toxicity, for dischargers not required to comply with numeric chronic toxicity effluent limitations, MMET tests are a maximum of two tests that are used in addition to the routine monitoring test to determine whether a TRE should be conducted. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-6 Most Sensitive Species The single species selected from an array of test species to be used in a single species laboratory test series to determine toxic effects of effluent or ambient water. Non-Continuous Dischargers Dischargers that do not discharge in a continuous manner or do not discharge throughout the calendar year (e.g., intermittent and seasonal dischargers). Non-NPDES Dischargers Dischargers of waste that could affect the quality of waters of the State that are not regulated by the NPDES program. Non-Stormwater NPDES Dischargers Dischargers that are regulated pursuant to one or more NPDES permit(s), but excluding any discharges subject to the United States Code title 33 section 1342(p). This includes dischargers that discharge a combination of treated municipal or industrial wastewater and stormwater. Nonpoint Source A source that does not meet the definition of a point source, as defined below. Not Detected (ND) Sample results which are less than the laboratory’s MDL. Null Hypothesis A statement used in statistical testing that has been put forward either because it is believed to be true or because it is to be used as a basis for argument, but has not been proved. Ocean Waters The territorial marine waters of the State, as defined by California law, to the extent these waters are outside of enclosed bays, estuaries, and coastal lagoons. Discharges to ocean waters are regulated in accordance with the State Water Board’s California Ocean Plan. Percent Effect The value that denotes the difference in response between the test concentration and the control, divided by the mean control response, and multiplied by 100. Permitting Authority The State Water Board or a regional water board that issues a permit, waste discharge requirements, water quality certification, or other authorization for the discharge or proposed discharge of waste. To the extent that the action is delegable, the term “Permitting Authority” can include the Executive Officer or Executive Director. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-7 Persistent Pollutants Persistent pollutants are substances for which degradation or decomposition in the environment is nonexistent or very slow. Point Source Any discernible, confined and discrete conveyance including, but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from which pollutants are or may be discharged. This term does not include agricultural stormwater discharges and return flows from irrigated agriculture. Pollutant Defined in section 502(6) of the CWA as “dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt and industrial, municipal, and agricultural waste discharged into water.” Pollutant Minimization Program (PMP) PMP means waste minimization and pollution prevention actions that include, but are not limited to, product substitution, waste stream recycling, alternative waste management methods, and education of the public and businesses. The goal of the PMP shall be to reduce all potential sources of a priority pollutant(s) through pollutant minimization (control) strategies, including pollution prevention measures as appropriate, to maintain the effluent concentration at or below the water quality-based effluent limitation. Pollution prevention measures may be particularly appropriate for persistent bioaccumulative priority pollutants where there is evidence that beneficial uses are being impacted. The Central Coast Water Board may consider cost effectiveness when establishing the requirements of a PMP. The completion and implementation of a Pollution Prevention Plan, if required pursuant to California Water Code section 13263.3(d), shall be considered to fulfill the PMP requirements. Pollution Prevention Pollution Prevention means any action that causes a net reduction in the use or generation of a hazardous substance or other pollutant that is discharged into water and includes, but is not limited to, input change, operational improvement, production process change, and product reformulation (as defined in California Water Code section 13263.3). Pollution prevention does not include actions that merely shift a pollutant in wastewater from one environmental medium to another environmental medium, unless clear environmental benefits of such an approach are identified to the satisfaction of the State Water Resources Control Board (State Water Board) or California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board). Publicly Owned Treatment Works (POTW) Facilities owned by a state or municipality that store, treat, recycle, and reclaim municipal sewage or industrial wastes of a liquid nature. Similar facilities that are privately, instead of publicly owned, are included in this definition for purposes of section III of the Toxicity Provisions. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-8 Reasonable Potential A designation used for a waste discharge that is projected or calculated to cause or contribute to an instream excursion above a water quality standard. Regulatory Management Decision (RMD) The decision that represents the maximum allowable error rates and thresholds for toxicity and non-toxicity that would result in an acceptable risk to aquatic life. Replicates Two or more independent organism exposures of the same treatment (i.e., effluent concentration) within a toxicity test. Replicates are typically conducted with separate test chambers and test organisms, each having the same effluent concentration. Reporting Level (RL) The RL is the ML (and its associated analytical method) chosen by the Discharger for reporting and compliance determination from the MLs included in this Order, including an additional factor if applicable as discussed herein. The MLs included in this Order correspond to approved analytical methods for reporting a sample result that are selected by the Central Coast Water Board either from Appendix 4 of the State Implementation Policy (SIP) in accordance with section 2.4.2 of the SIP or established in accordance with section 2.4.3 of the SIP. The ML is based on the proper application of method-based analytical procedures for sample preparation and the absence of any matrix interferences. Other factors may be applied to the ML depending on the specific sample preparation steps employed. For example, the treatment typically applied in cases where there are matrix-effects is to dilute the sample or sample aliquot by a factor of ten. In such cases, this additional factor must be applied to the ML in the computation of the RL. Response A measured biological effect (e.g., survival, reproduction, growth) as a result of exposure to a stimulus. Routine Monitoring Required monitoring that occurs during a permit term. Source of Drinking Water Any water designated as municipal or domestic supply (MUN) in a Central Coast Water Board Water Quality Control Plan for the Central Coastal Basin (Basin Plan). Species Sensitivity Screening An analysis to determine the single most sensitive species from an array of test species to be used in a single species laboratory test series. Standard Deviation (σ) Standard Deviation is a measure of variability that is calculated as follows: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-9 where: x is the observed value; µ is the arithmetic mean of the observed values; and n is the number of samples. Stormwater As defined at 40 C.F.R. section 122.26(b)(13) (Nov. 16, 1990) which states, ‘Storm water means storm water runoff, snow melt runoff, and surface runoff and drainage.” Test of Significant Toxicity (TST) A statistical approach used to analyze aquatic toxicity test data, as described in section IV.B.1.c of the Toxicity Provisions. Toxicity Identification Evaluation (TIE) Techniques used to identity the unexplained cause(s) of toxic event. A TIE involves selectively removing classes of chemicals through a series of sample manipulations, effectively reducing complex mixtures of chemicals in natural waters to simple components for analysis. Following each manipulation, the toxicity sample is assessed to see whether the toxicant class removed was responsible for the toxicity. Toxicity Reduction Evaluation (TRE) TRE is a study conducted in a step-wise process designed to identify the causative agents of effluent or ambient toxicity, isolate the sources of toxicity, evaluate the effectiveness of toxicity control options, and then confirm the reduction in toxicity. The first steps of the TRE consist of the collection of data relevant to the toxicity, including additional toxicity testing, and an evaluation of facility operations and maintenance practices, and best management practices. A Toxicity Identification Evaluation (TIE) may be required as part of the TRE, if appropriate. (A TIE is a set of procedures to identify the specific chemical(s) responsible for toxicity. These procedures are performed in three phases (characterization, identification, and confirmation) using aquatic organism toxicity tests.) Toxicity Provisions Refers to State Policy for Water Quality Control: Toxicity Provisions (adopted in 2020 and revised in 2021) of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT B-MAP B-1 B. ATTACHMENT B – MAP CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-1 C. ATTACHMENT C – FLOW SCHEMATIC CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-2 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-1 D. ATTACHMENT D – STANDARD PROVISIONS 1. STANDARD PROVISIONS – PERMIT COMPLIANCE 1.1. Duty to Comply 1.1.1. The Discharger must comply with all terms, requirements, and conditions of this Order. Any noncompliance constitutes a violation of the Clean Water Act (CWA) and the California Water Code (Water Code) and is grounds for enforcement action; permit termination, revocation and reissuance, or modification; denial of a permit renewal application; or a combination thereof. (40 Code of Federal Regulations (C.F.R.) 122.41(a); Water Code sections 13261, 13263, 13265, 13268, 13000, 13001, 13304, 13350, 13385.) 1.1.2. The Discharger shall comply with effluent standards or prohibitions established under Section 307(a) of the CWA for toxic pollutants within the time provided in the regulations that establish these standards or prohibitions, even if this Order has not yet been modified to incorporate the requirement. (40 C.F.R. 122.41(a)(1).) 1.2. Need to Halt or Reduce Activity Not a Defense It shall not be a defense for a Discharger in an enforcement action that it would have been necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this Order. (40 C.F.R. 122.41(c).) 1.3. Duty to Mitigate The Discharger shall take all reasonable steps to minimize or prevent any discharge in violation of this Order that has a reasonable likelihood of adversely affecting human health or the environment. (40 C.F.R. 122.41(d).) 1.4. Proper Operation and Maintenance The Discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the Discharger to achieve compliance with the conditions of this Order. Proper operation and maintenance also include adequate laboratory controls and appropriate quality assurance procedures. This provision requires the operation of backup or auxiliary facilities or similar systems that are installed by a Discharger only when necessary to achieve compliance with the conditions of this Order. (40 C.F.R. 122.41(e).) 1.5. Property Rights 1.5.1. This Order does not convey any property rights of any sort or any exclusive privileges. (40 C.F.R. 122.41(g).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-2 1.5.2. The issuance of this Order does not authorize any injury to persons or property or invasion of other private rights, or any infringement of state or local law or regulations. (40 C.F.R. 122.5(c).) 1.6. Inspection and Entry The Discharger shall allow the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board), State Water Resources Control Board (State Water Board), United States Environmental Protection Agency (U.S. EPA), and/or their authorized representatives (including an authorized contractor acting as their representative), upon the presentation of credentials and other documents, as may be required by law, to (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i); Water Code sections 13267, 13383): 1.6.1. Enter upon the Discharger's premises where a regulated facility or activity is located or conducted, or where records are kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(i); 40 C.F.R. 122.41(i)(1); Water Code sections 13267, 13383); 1.6.2. Have access to and copy, at reasonable times, any records that must be kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(2); Water Code sections 13267, 13383); 1.6.3. Inspect and photograph, at reasonable times, any facilities, equipment (including monitoring and control equipment), practices, or operations regulated or required under this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(3); Water Code sections 13267, 13383); and 1.6.4. Sample or monitor, at reasonable times, for the purposes of assuring Order compliance or as otherwise authorized by the CWA or the Water Code, any substances or parameters at any location. (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i)(4); Water Code sections 13267, 13383.) 1.7. Bypass 1.7.1. Definitions 1.7.1.1. “Bypass” means the intentional diversion of waste streams from any portion of a treatment facility. (40 C.F.R. 122.41(m)(1)(i).) 1.7.1.2. “Severe property damage” means substantial physical damage to property, damage to the treatment facilities, which causes them to become inoperable, or substantial and permanent loss of natural resources that can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production. (40 C.F.R. 122.41(m)(1)(ii).) 1.7.2. Bypass not exceeding limitations. The Discharger may allow any bypass to occur which does not cause exceedances of effluent limitations, but only if it is for essential maintenance to assure efficient operation. These bypasses are not subject to the provisions listed in Standard Provisions – Permit Compliance 1.7.3, 1.7.4, and 1.7.5 below. (40 C.F.R. 122.41(m)(2).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-3 1.7.3. Prohibition of bypass. Bypass is prohibited, and the Central Coast Water Board may take enforcement action against a Discharger for bypass, unless (40 C.F.R. 122.41(m)(4)(i)): 1.7.3.1. Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage (40 C.F.R. 122.41(m)(4)(i)(A)); 1.7.3.2. There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass that occurred during normal periods of equipment downtime or preventive maintenance (40 C.F.R. 122.41(m)(4)(i)(B)); and 1.7.3.3. The Discharger submitted notice to the Central Coast Water Board as required under Standard Provisions – Permit Compliance 1.7.5 below. (40 C.F.R. 122.41(m)(4)(i)(C).) 1.7.4. The Central Coast Water Board may approve an anticipated bypass, after considering its adverse effects, if the Central Coast Water Board determines that it will meet the three conditions listed in Standard Provisions – Permit Compliance 1.7.3 above. (40 C.F.R. 122.41(m)(4)(ii).) 1.7.5. Notice 1.7.5.1. Anticipated bypass. If the Discharger knows in advance of the need for a bypass, it shall submit prior notice, if possible, at least 10 days before the date of the bypass. The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part127. (40 C.F.R. 122.41(m)(3)(i).) 1.7.5.2. Unanticipated bypass. The Discharger shall submit a notice of an unanticipated bypass as required in Standard Provisions - Reporting 5.5 below (24-hour notice). The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(m)(3)(ii).) 1.8. Upset Upset means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the Discharger. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. (40 C.F.R. 122.41(n)(1).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-4 1.8.1. Effect of an upset. An upset constitutes an affirmative defense to an action brought for noncompliance with such technology-based permit effluent limitations if the requirements of Standard Provisions – Permit Compliance 1.8.2 below are met. No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review. (40 C.F.R. 122.41(n)(2).) 1.8.2 Conditions necessary for a demonstration of upset. A Discharger who wishes to establish the affirmative defense of upset shall demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that (40 C.F.R. 122.41(n)(3)): 1.8.2.1. An upset occurred and that the Discharger can identify the cause(s) of the upset (40 C.F.R. 122.41(n)(3)(i)); 1.8.2.2. The permitted facility was, at the time, being properly operated (40 C.F.R. 122.41(n)(3)(ii)); 1.8.2.3. The Discharger submitted notice of the upset as required in Standard Provisions – Reporting 5.5.2.2 below (24-hour notice) (40 C.F.R. 122.41(n)(3)(iii)); and 1.8.2.4. The Discharger complied with any remedial measures required under Standard Provisions – Permit Compliance 1.3 above. (40 C.F.R. 122.41(n)(3)(iv).) 1.8.3. Burden of proof. In any enforcement proceeding, the Discharger seeking to establish the occurrence of an upset has the burden of proof. (40 C.F.R. 122.41(n)(4).) 2. STANDARD PROVISIONS – PERMIT ACTION 2.1. General This Order may be modified, revoked and reissued, or terminated for cause. The filing of a request by the Discharger for modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not stay any Order condition. (40 C.F.R. 122.41(f).) 2.2. Duty to Reapply If the Discharger wishes to continue an activity regulated by this Order after the expiration date of this Order, the Discharger must apply for and obtain a new permit. (40 C.F.R. 122.41(b).) 2.3. Transfers This Order is not transferable to any person except after notice to the Central Coast Water Board. The Central Coast Water Board may require modification or revocation and reissuance of the Order to change the name of the Discharger and incorporate such other requirements as may be necessary under the CWA and the Water Code. (40 C.F.R. 122.41(l)(3), 122.61.) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-5 3. STANDARD PROVISIONS – MONITORING 3.1. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. (40 C.F.R. 122.41(j)(1).) 3.2. Monitoring must be conducted according to test procedures approved under 40 C.F.R. part 136 for the analyses of pollutants unless another method is required under 40 C.F.R. chapter 1, subchapter N. Monitoring must be conducted according to sufficiently sensitive test methods approved under 40 C.F.R. part 136 for the analysis of pollutants or pollutant parameters or as required under 40 C.F.R. chapter 1, subchapter N. For the purposes of this paragraph, a method is sufficiently sensitive when: 3.2.1. The method minimum level (ML) is at or below the level of the most stringent effluent limitation established in the permit for the measured pollutant or pollutant parameter, and either the method ML is at or below the level of the most stringent applicable water quality criterion for the measured pollutant or pollutant parameter or the method ML is above the applicable water quality criterion but the amount of the pollutant or pollutant parameter in the facility’s discharge is high enough that the method detects and quantifies the level of the pollutant or pollutant parameter in the discharge; or 3.2.2. The method has the lowest ML of the analytical methods approved under 40 C.F.R. part 136 or required under 40 C.F.R. chapter 1, subchapter N for the measured pollutant or pollutant parameter. In the case of pollutants or pollutant parameters for which there are no approved methods under 40 C.F.R. part 136, or otherwise required under 40 C.F.R. chapter 1, subchapter N, monitoring must be conducted according to a test procedure specified in this Order for such pollutants or pollutant parameters. (40 C.F.R. 122.21(e)(3), 122.41(j)(4), 122.44(i)(1)(iv).) 4. STANDARD PROVISIONS – RECORDS 4.1. The Discharger shall retain records of all monitoring information, including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation, copies of all reports required by this Order, and records of all data used to complete the application for this Order, for a period of at least three (3) years from the date of the sample, measurement, report or application. This period may be extended by request of the Central Coast Water Board Executive Officer at any time. (40 C.F.R. 122.41(j)(2).) 4.2. Records of monitoring information shall include: 4.2.1. The date, exact place, and time of sampling or measurements (40 C.F.R. 122.41(j)(3)(i)); 4.2.2. The individual(s) who performed the sampling or measurements (40 C.F.R. 122.41(j)(3)(ii)); 4.2.3. The date(s) analyses were performed (40 C.F.R. 122.41(j)(3)(iii)); CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-6 4.2.4. The individual(s) who performed the analyses (40 C.F.R. 122.41(j)(3)(iv)); 4.2.5. The analytical techniques or methods used (40 C.F.R. 122.41(j)(3)(v)); and 4.2.6. The results of such analyses. (40 C.F.R. 122.41(j)(3)(vi).) 4.3. Claims of confidentiality for the following information will be denied (40 C.F.R. 122.7(b)): 4.3.1. The name and address of any permit applicant or Discharger (40 C.F.R. 122.7(b)(1)); and 4.3.2. Permit applications and included attachments, permits, and effluent data. (40 C.F.R. 122.7(b)(2).) 5. STANDARD PROVISIONS – REPORTING 5.1. Duty to Provide Information The Discharger shall furnish to the Central Coast Water Board, State Water Board, or U.S. EPA within a reasonable time, any information which the Central Coast Water Board, State Water Board, or U.S. EPA may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this Order or to determine compliance with this Order. Upon request, the Discharger shall also furnish to the Central Coast Water Board, State Water Board, or U.S. EPA copies of records required to be kept by this Order. (40 C.F.R. 122.41(h); Water Code sections 13267, 13383.) 5.2. Signatory and Certification Requirements 5.2.1. All applications, reports, or information submitted to the Central Coast Water Board, State Water Board, and/or U.S. EPA shall be signed and certified in accordance with Standard Provisions – Reporting 5.2.2, 5.2.3, 5.2.4, 5.2.5, and 5.2.6 below. (40 C.F.R. 122.41(k).) 5.2.2. All permit applications shall be signed by a responsible corporate officer. For the purpose of this section, a responsible corporate officer means: (i) A president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy- or decision- making functions for the corporation, or (ii) the manager of one or more manufacturing, production, or operating facilities, provided, the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmental compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures. (40 C.F.R. 122.22(a)(1).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-7 5.2.3. All reports required by this Order and other information requested by the Central Coast Water Board, State Water Board, or U.S. EPA shall be signed by a person described in Standard Provisions – Reporting 5.2.2 above, or by a duly authorized representative of that person. A person is a duly authorized representative only if: 5.2.3.1. The authorization is made in writing by a person described in Standard Provisions – Reporting 5.2.2 above (40 C.F.R. 122.22(b)(1)); 5.2.3.2. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the company. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.) (40 C.F.R. 122.22(b)(2)); and 5.2.3.3. The written authorization is submitted to the Central Coast Water Board and State Water Board. (40 C.F.R. 122.22(b)(3).) 5.2.4. If an authorization under Standard Provisions – Reporting 5.2.3 above is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of Standard Provisions – Reporting 5.2.3 above must be submitted to the Central Coast Water Board and State Water Board prior to or together with any reports, information, or applications, to be signed by an authorized representative. (40 C.F.R. 122.22(c).) 5.2.5. Any person signing a document under Standard Provisions – Reporting 5.2.2 or 5.2.3 above shall make the following certification: “I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.” (40 C.F.R. 122.22(d).) 5.2.6. Any person providing the electronic signature for documents described in Standard Provisions – 5.2.1, 5.2.2, or 5.2.3 that are submitted electronically shall meet all relevant requirements of Standard Provisions – Reporting 5.2, and shall ensure that all relevant requirements of 40 C.F.R. part 3 (Cross-Media Electronic Reporting) and 40 C.F.R. part 127 (NPDES Electronic Reporting Requirements) are met for that submission. (40 C.F.R 122.22(e).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-8 5.3. Monitoring Reports 5.3.1. Monitoring results shall be reported at the intervals specified in the Monitoring and Reporting Program (Attachment E) in this Order. (40 C.F.R. 122.41(l)(4).) 5.3.2. Monitoring results must be reported on a Discharge Monitoring Report (DMR) form or forms provided or specified by the Central Coast Water Board or State Water Board. All reports and forms must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 and comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(l)(4)(i).) 5.3.3. If the Discharger monitors any pollutant more frequently than required by this Order using test procedures approved under 40 C.F.R. part 136, or another method required for an industry-specific waste stream under 40 C.F.R. chapter 1, subchapter N, the results of such monitoring shall be included in the calculation and reporting of the data submitted in the DMR or reporting form specified by the Central Coast Water Board or State Water Board. (40 C.F.R. 122.41(l)(4)(ii).) 5.3.4. Calculations for all limitations, which require averaging of measurements, shall utilize an arithmetic mean unless otherwise specified in this Order. (40 C.F.R. 122.41(l)(4)(iii).) 5.4. Compliance Schedules Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule of this Order, shall be submitted no later than 14 days following each schedule date. (40 C.F.R. 122.41(l)(5).) 5.5. Twenty-Four Hour Reporting 5.5.1. The Discharger shall report any noncompliance which may endanger health or the environment. Any information shall be provided orally within 24 hours from the time the Discharger becomes aware of the circumstances. A report shall also be provided within five (5) days of the time the Discharger becomes aware of the circumstances. The report shall contain a description of the noncompliance and its cause; the period of noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports must include the data described above (with the exception of time of discovery) as well as the type of event (i.e., combined sewer overflow, sanitary sewer overflow, or bypass event), type of overflow structure (e.g., manhole, combined sewer overflow outfall), discharge volume untreated by the treatment works treating domestic sewage, types of human health and environmental impacts of the event, and whether the noncompliance was related to wet weather. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-9 As of December 21, 2023, all reports related to combined sewer overflows, sanitary sewer overflows, or bypass events must be submitted to the Central Coast Water Board and must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 The reports shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(6)(i).) 5.5.2. The following shall be included as information that must be reported within 24 hours: 5.5.2.1. Any unanticipated bypass that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(A).) 5.5.2.2. Any upset that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.5.3. The Central Coast Water Board may waive the above required written report on a case-by-case basis if an oral report has been received within 24 hours. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.6. Planned Changes The Discharger shall give notice to the Central Coast Water Board as soon as possible of any planned physical alterations or additions to the permitted facility. Notice is required under this provision only when (40 C.F.R. 122.41(l)(1)): 5.6.1. The alteration or addition to a permitted facility may meet one of the criteria for determining whether a facility is a new source in section 122.29(b) (40 C.F.R. 122.41(l)(1)(i)); or 5.6.2. The alteration or addition could significantly change the nature or increase the quantity of pollutants discharged. This notification applies to pollutants that are not subject to effluent limitations in this Order. (40 C.F.R. 122.41(l)(1)(ii).); or 5.7. Anticipated Noncompliance The Discharger shall give advance notice to the Central Coast Water Board of any planned changes in the permitted facility or activity that may result in noncompliance with this Order’s requirements. (40 C.F.R. 122.41(l)(2).) 5.8. Other Noncompliance The Discharger shall report all instances of noncompliance not reported under Standard Provisions – Reporting 5.3, 5.4, and 5.5 above at the time monitoring reports are submitted. The reports shall contain the information listed in Standard Provision – Reporting 5.5 above. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports shall contain the information described in Standard Provision – Reporting 5.5 and the applicable required data in appendix A to 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-10 related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(7).) 5.9 Other Information When the Discharger becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or in any report to the Central Coast Water Board, State Water Board, or U.S. EPA, the Discharger shall promptly submit such facts or information. (40 C.F.R. 122.41(l)(8).) 5.10. Initial Recipient for Electronic Reporting Data The owner, operator, or the duly authorized representative is required to electronically submit NPDES information specified in appendix A to 40 C.F.R. part 127 to the initial recipient defined in 40 C.F.R. section 127.2(b). U.S. EPA will identify and publish the list of initial recipients on its website and in the Federal Register, by state and by NPDES data group [see 40 C.F.R. 127.2(c)]. U.S. EPA will update and maintain this listing. (40 C.F.R. 122.41(l)(9).) 6. STANDARD PROVISIONS – ENFORCEMENT 6.1. The Central Coast Water Board is authorized to enforce the terms of this permit under several provisions of the Water Code, including, but not limited to, sections 13268, 13350, 13385, 13386, and 13387. 7. ADDITIONAL PROVISIONS – NOTIFICATION LEVELS 7.1. Non-Municipal Facilities Existing manufacturing, commercial, mining, and silvicultural Dischargers shall notify the Central Coast Water Board as soon as they know or have reason to believe (40 C.F.R. 122.42(a)): 7.1.1. That any activity has occurred or will occur that would result in the discharge, on a routine or frequent basis, of any toxic pollutant that is not limited in this Order, if that discharge will exceed the highest of the following "notification levels" (40 C.F.R. 122.42(a)(1)): 7.1.1.1. 100 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(1)(i)); 7.1.1.2. 200 μg/L for acrolein and acrylonitrile; 500 μg/L for 2,4 dinitrophenol and 2-methyl 4,6 dinitrophenol; and 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(1)(ii)); 7.1.1.3. Five (5) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(1)(iii)); or 7.1.1.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(1)(iv).) 7.1.2. That any activity has occurred or will occur that would result in the discharge, on a non-routine or infrequent basis, of any toxic pollutant that is not limited in this CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-11 Order, if that discharge will exceed the highest of the following “notification levels" (40 C.F.R. 122.42(a)(2)): 7.1.2.1. 500 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(2)(i)); 7.1.2.2. 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(2)(ii)); 7.1.2.3. Ten (10) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(2)(iii)); or 7.1.2.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(2)(iv).) 7.2 Publicly Owned Treatment Works (POTWs) All POTWs shall provide adequate notice to the Central Coast Water Board of the following (40 C.F.R. 122.42(b)): 7.2.1. Any new introduction of pollutants into the POTW from an indirect discharger that would be subject to sections 301 or 306 of the CWA if it were directly discharging those pollutants (40 C.F.R. 122.42(b)(1)); and 7.2.2. Any substantial change in the volume or character of pollutants being introduced into that POTW by a source introducing pollutants into the POTW at the time of adoption of the Order. (40 C.F.R. 122.42(b)(2).) 7.2.3. Adequate notice shall include information on the quality and quantity of effluent introduced into the POTW as well as any anticipated impact of the change on the quantity or quality of effluent to be discharged from the POTW. (40 C.F.R. 122.42(b)(3).) 8. CENTRAL COAST WATER BOARD STANDARD PROVISIONS 8.1. Central Coast Standard Provision – Prohibitions 8.1.1. Introduction of “incompatible wastes” to the treatment system is prohibited. 8.1.2. Discharge of high-level radiological waste and of radiological, chemical, and biological warfare agents is prohibited. 8.1.3. Discharge of “toxic pollutants” in violation of effluent standards and prohibitions established under section 307(a) of the CWA is prohibited. 8.1.4. Discharge of sludge, sludge digester or thickener supernatant, and sludge drying bed leachate to drainageways, surface waters, or the ocean is prohibited. 8.1.5. Introduction of pollutants into the collection, treatment, or disposal system by and “indirect discharger” that: 8.1.5.1. Inhibit or disrupt the treatment process, system operation, or the eventual use or disposal of sludge; or, 8.1.5.2. Flow through the system to the receiving water untreated; and, 8.1.5.3. Cause or “significantly contribute” to a violation of any requirement of this Order, is prohibited. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-12 8.1.6. Introduction of “pollutant free” wastewater to the collection, treatment, and disposal system in amounts that threaten compliance with this order is prohibited. 8.2. Central Coast Standard Provisions 8.2.1. Collection, treatment, and discharge of waste shall not create a nuisance or pollution, as defined by Water Code section 13050. 8.2.2. All facilities used for transport or treatment of wastes shall be adequately protected from inundation and washout as the result of a 100-year frequency flood. 8.2.3. Operation of collection, treatment, and disposal systems shall be in a manner that precludes public contact with wastewater. 8.2.4. Collected screenings, sludges, and other solids removed from liquid wastes shall be disposed in a manner approved by the Executive Officer. 8.2.5. Publicly owned wastewater treatment plans shall be supervised and operated by persons possessing certificates of appropriate grade pursuant to title 23 of the California Administrative Code. 8.2.6. After notice and opportunity for a hearing, this order may be terminated for cause, including, but not limited to: 8.2.6.1. Violation of any term or condition contained in this order; 8.2.6.2. Obtaining this order by misrepresentation, or by failure to disclose fully all relevant facts; 8.2.6.3. A change in any condition or endangerment to human health or environment that requires a temporary or permanent reduction or elimination of the authorized discharge; and, 8.2.6.4. A substantial change in character, location, or volume of the discharge. 8.2.7. Provisions of this permit are severable. If any provision of the permit is found invalid, the remainder of the permit shall not be affected. 8.2.8. After notice and opportunity for hearing, this order may be modified or revoked and reissued for cause, including: 8.2.8.1. Promulgation of a new or revised effluent standard or limitation; 8.2.8.2. A material change in character, location, or volume of the discharge; 8.2.8.3. Access to new information that affects the germs of the permit, including applicable schedules; 8.2.8.4. Correction of technical mistakes or mistaken interpretations of law; and, 8.2.8.5. Other causes set forth under Sub-part D of 40 C.F.R. part 122. 8.2.9. Safeguards shall be provided to ensure maximal compliance with all terms and conditions of this permit. Safeguards shall include preventative and contingency plans and may also include alternative power sources, stand-by generators, retention capacity, operative procedures, or other precautions. Preventative and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-13 contingency plans for controlling and minimizing the effect of accidental discharges shall: 8.2.9.1. Identify possible situations that could cause “upset,” “overflow,” or “bypass,” or other noncompliance. (Loading and storage areas, power outage, waste treatment unit outage, and failure of process equipment, tanks and pipes should be considered). 8.2.9.2. Evaluate the effectiveness of present facilities and procedures and describe procedures and steps to minimize or correct any adverse environmental impact resulting from noncompliance with the permit. 8.2.10. Physical Facilities shall be designed and constructed according to accepted engineering practice and shall be capable of full compliance with this order when properly operated and maintained. Proper operation and maintenance shall be described in an Operation and Maintenance Manual. Facilities shall be accessible during the wet-weather season. 8.2.11. The discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) that are installed or used by the discharger to achieve compliance with the conditions of this order. Electrical and mechanical equipment shall be maintained in accordance with appropriate practices and standards, such as NFPA 70B, Recommended Practice for Electrical Equipment Maintenance; NFPA 70E, Standard for Electrical Safety in the Workplace; ANSI/NETA MTS Standard for Maintenance: Testing Specifications for Electrical Power Equipment and Systems, or procedures established by insurance companies or industry resources. 8.2.12. If the discharger’s facilities are equipped with SCADA or other systems that implement wireless, remote operation, the discharger should implement appropriate safeguards against unauthorized access to the wireless systems. Standards such as NIST SP 800-53, Recommended Security Controls for Federal Information Systems, can provide guidance. 8.2.13. Production and use of reclaimed water is subject to the approval of the Central Coast Water Board. Production and use of reclaimed water shall be in conformance with recycling criteria established in chapter 3, title 22, of the California Administrative Code and chapter 7, division 7, of the Water Code. An engineering report pursuant to section 60323, title 22, of the California Administrative Code is required and a waiver or water recycling requirements from the Central Coast Water Board is required before reclaimed water is supplied for any use, or to any user, not specifically identified and approved either in this Order or another order issued by the Central Coast Water Board. 8.3. Central Coast Standard Provisions – General Monitoring Requirements 8.3.1. If results of monitoring a pollutant appear to violate effluent limitations based on a weekly, monthly, 30-day, or six-month period, but compliance or non-compliance cannot be validated because sampling is too infrequent, the frequency of sampling shall be increased to validate the test within the next monitoring period. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-14 The increased frequency shall be maintained until the Executive Officer agrees the original monitoring frequency may be resumed. For example, if copper is monitored annually and results exceed the six-month median numerical effluent limitation in the permit, monitoring of copper must be increased to a frequency of at least once every two months (Central Coast Standard Provisions – Definitions 1.7.13.). If suspended solids are monitored weekly and results exceed the weekly average numerical limit in the permit, monitoring of suspended solids must be increased to at least four (4) samples every week (Central Coast Standard Provisions – Definitions 1.7.14.). 8.3.2. Water quality analyses performed in order to monitor compliance with this permit shall be by a laboratory certified by the Division of Drinking Water for the constituent(s) being analyzed. Bioassay(s) performed in order to monitor compliance with this permit shall be in accord with guidelines approved by the State Water Board and the California Department of Fish and Wildlife. If the laboratory used or proposed for use by the discharger is not certified by the Division of Drinking Water or, where appropriate, the Department of Fish and Wildlife due to restrictions in the State's laboratory certification program, the discharger shall be considered in compliance with this provision provided: 8.3.2.1. Data results remain consistent with results of samples analyzed by the Central Coast Water Board; 8.3.2.2. A quality assurance program is used at the laboratory, including a manual containing steps followed in this program that is available for inspections by the staff of the Central Coast Water Board; and, 8.3.2.3. Certification is pursued in good faith and obtained as soon as possible after the program is reinstated. 8.3.3. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. Samples shall be taken during periods of peak loading conditions. Influent samples shall be samples collected from the combined flows of all incoming wastes, excluding recycled wastes. Effluent samples shall be samples collected downstream of the last treatment unit and tributary flow and upstream of any mixing with receiving waters. 8.3.4. All monitoring instruments and devices used by the discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. 8.4. Central Coast Standard Provisions – General Reporting Requirements 8.4.1. Reports of marine monitoring surveys conducted to meet receiving water monitoring requirements of the Monitoring and Reporting Program shall include at least the following information: 8.4.1.1. A description of climatic and receiving water characteristics at the time of sampling (weather observations, floating debris, discoloration, wind speed and direction, swell or wave action, time of sampling, tide height, etc.). CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-15 8.4.1.2. A description of sampling stations, including differences unique to each station (e.g., station location, grain size, rocks, shell litter, calcareous worm tubes, evident life, etc.). 8.4.1.3. A description of the sampling procedures and preservation sequence used in the survey. 8.4.1.4. A description of the exact method used for laboratory analysis. In general, analysis shall be conducted according to Central Coast Standard Provisions – 8.3.1 above, and Federal Standard Provision – Monitoring 3.2. However, variations in procedure are acceptable to accommodate the special requirements of sediment analysis. All such variations must be reported with the test results. 8.4.1.5. A brief discussion of the results of the survey. The discussion shall compare data from the control station with data from the outfall stations. All tabulations and computations shall be explained. 8.4.2. Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule shall be submitted within 14 days following each scheduled date unless otherwise specified within the permit. If reporting noncompliance, the report shall include a description of the reason, a description and schedule of tasks necessary to achieve compliance, and an estimated date for achieving full compliance. A second report shall be submitted within 14 days of full compliance. 8.4.3. The Discharger shall file a Report of Waste Discharge or secure a waiver from the Executive Officer at least 180 days before making any material change or proposed change in the character, location, or plume of the discharge. 8.4.4. Within 120 days after the Discharger discovers, or is notified by the Central Coast Water Board, that monthly average daily flow will or may reach design capacity of waste treatment and/or disposal facilities within four (4) years, the Discharger shall file a written report with the Central Coast Water Board. The report shall include: 8.4.4.1. The best estimate of when the monthly average daily dry weather flow rate will equal or exceed design capacity; and, 8.4.4.2. A schedule for studies, design, and other steps needed to provide additional capacity for waste treatment and/or disposal facilities before the waste flow rate equals the capacity of present units. In addition to complying with Federal Standard Provision – Reporting 5.2, the required technical report shall be prepared with public participation and reviewed, approved and jointly submitted by all planning and building departments having jurisdiction in the area served by the waste collection, treatment, or disposal facilities. 8.4.5. All Dischargers shall submit reports electronically to the: California Regional Water Quality Control Board Central Coast Region CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-16 centralcoast@waterboards.ca.gov 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 In addition, Dischargers with designated major discharges shall submit a copy of each document to: Regional Administrator U.S. EPA, Region 9 Attention: CWA Standards and Permits Office (WTR-5) 75 Hawthorne Street San Francisco, California 94105 8.4.6. Transfer of control or ownership of a waste discharge facility must be preceded by a notice to the Central Coast Water Board at least 30 days in advance of the proposed transfer date. The notice must include a written agreement between the existing Discharger and proposed Discharger containing specific date for transfer of responsibility, coverage, and liability between them. Whether a permit may be transferred without modification or revocation and reissuance is at the discretion of the Board. If permit modification or revocation and reissuance is necessary, transfer may be delayed 180 days after the Central Coast Water Board's receipt of a complete permit application. Please also see Federal Standard Provision – Permit Action 2.3. 8.4.7. Except for data determined to be confidential under CWA section 308 (excludes effluent data and permit applications), all reports prepared in accordance with this permit shall be available for public inspection at the office of the Central Coast Water Board or Regional Administrator of U.S. EPA. Please also see Federal Standard Provision – Records 4.3. 8.4.8. By February 1st of each year, the discharger shall submit an annual report to the Central Coast Water Board. The report shall contain the following: 8.4.8.1. Both tabular and graphical summaries of the monitoring data obtained during the previous year. 8.4.8.2. A discussion of the previous year’s compliance record and corrective actions taken, or which may be needed, to bring the discharger into full compliance. 8.4.8.3. An evaluation of wastewater flows with projected flow rate increases over time and the estimated date when flows will reach facility capacity. 8.4.8.4. A discussion of operator certification and a list of current operating personnel and their grades of certification. 8.4.8.5. The date of the facility’s Operation and Maintenance Manual (including contingency plans as described in Provision 8.2.9), the date the manual was last reviewed, and whether the manual is complete and valid for the current facility. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-17 8.4.8.6. A discussion of the laboratories used by the discharger to monitor compliance with effluent limits and a summary of performance relative to section 8.3, General Monitoring Requirements. 8.4.8.7. If the facility treats industrial or domestic wastewater and there is no provision for periodic sludge monitoring in the Monitoring and Reporting Program, the report shall include a summary of sludge quantities, analyses of its chemical and moisture content, and its ultimate destination. 8.4.8.8. If appropriate, the report shall also evaluate the effectiveness of the local source control or pretreatment program using the State Water Board's "Guidelines for Determining the Effectiveness of Local Pretreatment Program." 8.5. Central Coast Standard Provisions – General Pretreatment Provisions 8.5.1. Discharge of pollutants by "indirect dischargers” in specific industrial sub- categories (appendix C, 40 C.F.R. part 403), where categorical pretreatment standards have been established, or are to be established, (according to 40 C.F.R. chapter 1, subchapter N), shall comply with the appropriate pretreatment standards: 8.5.1.1. By the date specified therein; 8.5.1.2. Within three (3) years of the effective date specified therein, but in no case later than July 1, 1984; or, 8.5.1.3. If a new indirect discharger, upon commencement of discharge. 8.6. Central Coast Standard Provision – Enforcement 8.6.1. Any person failing to file a Report of Waste Discharge or other report as required by this permit shall be subject to a civil penalty not to exceed $5,000 per day. 8.6.2. Upon reduction, loss, or failure of the treatment facility, the Discharger shall, to the extent necessary to maintain compliance with this permit, control production or all discharges, or both, until the facility is restored or an alternative method of treatment is provided. 8.7. Central Coast Standard Provisions – Definitions (Not otherwise included in Attachment A to this Order) 8.7.1. A “composite sample" is a combination of no fewer than eight (8) individual samples obtained at equal time intervals (usually hourly) over the specified sampling (composite) period. The volume of each individual sample is proportional to the flow rate at the time of sampling. The period shall be specified in the Monitoring and Reporting Program ordered by the Executive Officer. 8.7.2. “Daily Maximum” limit means the maximum acceptable concentration or mass emission rate of a pollutant measured during a calendar day or during any 24- hour period reasonably representative of the calendar day for purposes of sampling. It is normally compared with results based on "composite samples” except for ammonia, total chlorine, phenolic compounds, and toxicity CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-18 concentration. For all exceptions, comparisons will be made with results from a “grab sample”. 8.7.3. “Discharger", as used herein, means, as appropriate: (1) the Discharger, (2) the local sewering entity (when the collection system is not owned and operated by the Discharger), or (3) "indirect discharger" (where "Discharger" appears in the same paragraph as "indirect discharger”, it refers to the discharger.) 8.7.4. “Duly Authorized Representative" is one where: 8.7.4.1. The authorization is made in writing by a person described in the signatory paragraph of Federal Standard Provision 5.2.; 8.7.4.2. The authorization specifies either an individual or the occupant of a position having either responsibility for the overall operation of the regulated facility, such as the plant manager, or overall responsibility for environmental matters of the company; and, 8.7.4.3. The written authorization was submitted to the Central Coast Water Board. 8.7.5. A "grab sample" is defined as any individual sample collected in less than 15 minutes. "Grab samples” shall be collected during peak loading conditions, which may or may not be during hydraulic peaks. It is used primarily in determining compliance with the daily maximum limits identified in Central Coast Standard Provision – Provision 8.7.2. and instantaneous maximum limits. 8.7.6. "Hazardous substance” means any substance designated under 40 C.F.R. part 116 pursuant to section 311 of the CWA. 8.7.7. "Incompatible wastes” are: 8.7.7.1. Wastes which create a fire or explosion hazard in the treatment works; 8.7.7.2. Wastes which will cause corrosive structural damage to treatment works, but in no case wastes with a pH lower than 5.0 unless the works is specifically designed to accommodate such wastes; 8.7.7.3. Solid or viscous wastes in amounts which cause obstruction to flow in sewers, or which cause other interference with proper operation of treatment works; 8.7.7.4. Any waste, including oxygen demanding pollutants (BOD, etc.), released in such volume or strength as to cause inhibition or disruption in the treatment works and subsequent treatment process upset and loss of treatment efficiency; and, 8.7.7.5. Heat in amounts that inhibit or disrupt biological activity in the treatment works or that raise influent temperatures above 40°C (104°F) unless the treatment works is designed to accommodate such heat. 8.7.8. "Indirect Discharger” means a non-domestic discharger introducing pollutants into a publicly owned treatment and disposal system. 8.7.9. "Log Mean” is the geometric mean. Used for determining compliance of fecal or total coliform populations, it is calculated with the following equation: Log Mean = (C1 x C2 x...x Cn)1/n, CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-19 in which “n" is the number of days samples were analyzed during the period and any "C" is the concentration of bacteria (MPN/100 mL) found on each day of sampling. "n” should be five or more. 8.7.10. “Mass emission rate" is a daily rate defined by the following equations: mass emission rate (lbs/day) = 8.34 x Q x C; and, mass emission rate (kg/day) = 3.79 x Q x C, where “C" (in mg/L) is the measured daily constituent concentration or the average of measured daily constituent concentrations and “Q” (in MGD) is the measured daily flowrate or the average of measured daily flow rates over the period of interest. 8.7.11. The "Maximum Allowable Mass Emission Rate," whether for a month, week, day, or six-month period, is a daily rate determined with the formulas in paragraph 8.7.10, above, using the effluent concentration limit specified in the permit for the period and the average of measured daily flows (up to the allowable flow) over the period. 8.7.12. “Maximum Allowable Six-Month Median Mass Emission Rate" is a daily rate determined with the formulas in Central Coast Standard Provision – Provision 8.7.10, above, using the "six-month Median" effluent limit specified in the permit, and the average of measured daily flows (up to the allowable flow) over a 180-day period. 8.7.13. "Median" is the value below which half the samples (ranked progressively by increasing value) fall. It may be considered the middle value, or the average of two middle values. 8.7.14. "Monthly Average" (or "Weekly Average”, as the case may be) is the arithmetic mean of daily concentrations or of daily mass emission rates over the specified 30-day (or 7-day) period. Average = (X1 + X2 + ... + Xn) / n in which “n" is the number of days samples were analyzed during the period and “X" is either the constituent concentration (mg/l) or mass emission rate (kg/day or lbs/day) for each sampled day. “n" should be four or greater. 8.7.15. "Municipality" means a city, town, borough, county, district, association, or other public body created by or under State law and having jurisdiction over disposal of sewage, industrial waste, or other waste. 8.7.16. "Overflow" means the intentional or unintentional diversion of flow from the collection and transport systems, including pumping facilities. 8.7.17. "Pollutant-free wastewater" means inflow and infiltration, stormwaters, and cooling waters and condensates which are essentially free of pollutants. 8.7.18. "Primary Industry Category" means any industry category listed in 40 C.F.R. part 122, Appendix A. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-20 8.7.19. "Removal Efficiency" is the ratio of pollutants removed by the treatment unit to pollutants entering the treatment unit. Removal efficiencies of a treatment plant shall be determined using “Monthly averages" of pollutant concentrations (C, in mg/l) of influent and effluent samples collected about the same time and the following equation (or its equivalent): 8.7.20. "Severe property damage" means substantial physical damage to property, damage to treatment facilities which causes them to become inoperable, or substantial and permanent loss to natural resources which can reasonably be expected to occur in the absence of a "bypass”. It does not mean economic loss caused by delays in production. 8.7.21. "Sludge" means the solids, residues, and precipitates separated from, or created in, wastewater by the unit processes of a treatment system. 8.7.22. To "significantly contribute" to a permit violation means an "indirect discharger" must: 8.7.22.1. Discharge a daily pollutant loading in excess of that allowed by contract with the Discharger or by Federal, State, or Local law; 8.7.22.2. Discharge wastewater which substantially differs in nature or constituents from its average discharge; 8.7.22.3. Discharge pollutants, either alone or in conjunction with discharges from other sources, which results in a permit violation or prevents sewage sludge use or disposal; or 8.7.22.4. Discharge pollutants, either alone or in conjunction with pollutants from other sources that increase the magnitude or duration of permit violations. 8.7.23. "Toxic Pollutant" means any pollutant listed as toxic under Section 307 (a) (1) of the CWA or under 40 C.F.R. part 122, Appendix D. Violation of maximum daily discharge limitations are subject to 24-hour reporting (Federal Standard Provisions 5.5.). 8.7.24. “Zone of Initial Dilution" means the region surrounding or adjacent to the end of an outfall pipe or diffuser ports whose boundaries are defined through calculation of a plume model verified by the State Water Board. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-1 E. ATTACHMENT E – MONITORING AND REPORTING PROGRAM TABLE OF CONTENTS 1. GENERAL MONITORING PROVISIONS .................................................................E-2 2. MONITORING LOCATIONS ....................................................................................E-3 3. INFLUENT MONITORING REQUIREMENTS ..........................................................E-5 3.1. Monitoring Location INF-001 .................................................................................E-5 4. EFFLUENT MONITORING REQUIREMENTS .........................................................E-5 4.1. Monitoring Location EFF-001 ................................................................................E-5 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS .................................E-9 5.1. Whole Effluent Acute Toxicity Testing ...................................................................E-9 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable .............. E-18 7. RECYCLING MONITORING REQUIREMENTS .................................................... E-18 7.1. Monitoring Location RCY-001 ............................................................................. E-18 8. RECEIVING WATER MONITORING REQUIREMENTS ........................................ E-19 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW- 006, RSW-007, and RSW-008 .............................................................................. E-19 9. OTHER MONITORING REQUIREMENTS ............................................................. E-21 9.1. Biosolids, Monitoring, and Notification – BIO-001 ............................................... E-21 9.2. Pretreatment Monitoring ...................................................................................... E-26 9.3. Salt and Nutrient Management Plan Reporting ................................................... E-29 9.4. Volumetric Monitoring of Wastewater and Recycled Water ................................. E-30 10. REPORTING REQUIREMENTS .......................................................................... E-30 10.1. General Monitoring and Reporting Requirements ............................................. E-30 10.2. Self-Monitoring Reports (SMRs)........................................................................ E-30 10.3. Discharge Monitoring Reports (DMRs) .............................................................. E-34 10.4. Other Reports .................................................................................................... E-34 TABLE OF TABLES Table E-1. Monitoring Station Locations .......................................................................E-3 Table E-2. Influent Monitoring ......................................................................................E-5 Table E-3. Effluent Monitoring at EFF-001 ...................................................................E-6 Table E-4. Approved Test for Acute Toxicity – Fresh Water ...................................... E-10 Table E-5. Approved Tests for Chronic Toxicity – Freshwater ............................ E-14 Table E-6. Recycled Water Monitoring Requirements at RCY-001 ............................ E-18 Table E-6. Receiving Water Monitoring Requirements............................................... E-19 Table E-8. Amount of Biosolids and Frequency of Analysis ....................................... E-21 Table E-9. Biosolids Monitoring Requirements .......................................................... E-22 Table E-10. Monitoring Periods and Reporting Schedule........................................... E-31 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-2 ATTACHMENT E – MONITORING AND REPORTING PROGRAM Section 308 of the federal Clean Water Act (CWA) and sections 122.41(h), (j)-(l), 122.44(i), and 122.48 of title 40 of the Code of Federal Regulations (40 C.F.R.) require that all NPDES permits specify monitoring and reporting requirements. California Water Code sections 13267 and 13383 also authorize the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) to establish monitoring, inspection, entry, reporting, and recordkeeping requirements. This Monitoring and Reporting Program (MRP) establishes monitoring, reporting, and recordkeeping requirements that implement the federal and California laws and/or regulations. 1. GENERAL MONITORING PROVISIONS 1.1. Laboratories analyzing monitoring samples shall be certified by the State Water Resources Control Board (State Water Board), in accordance with the provision of California Water Code section 13176, and must include quality assurance/quality control data with their reports. 1.2. Samples and measurements taken as required herein shall be representative of the volume and nature of the monitored discharge. All samples shall be taken at the monitoring locations specified in this MRP and, unless otherwise specified, before the monitored flow joins or is diluted by any other waste stream, body of water, or substance. Monitoring locations shall not be changed without notification to and approval of the Central Coast Water Board. 1.3. Appropriate flow measurement devices and methods consistent with accepted scientific practices shall be selected and used to ensure the accuracy and reliability of measurements of the volume of monitored discharges. The devices shall be installed, calibrated, and maintained to ensure that the accuracy of the measurements is consistent with the accepted capability of that type of device. Devices selected shall be capable of measuring flows with a maximum deviation of less than ±10 percent from true discharge rates throughout the range of expected discharge volumes. Guidance in selection, installation, calibration, and operation of acceptable flow measurement devices can be obtained from the following references. 1.3.1. A Guide to Methods and Standards for the Measurement of Water Flow, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 421, May 1975, 96 pp. http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication421.pdf 1.3.2. Water Measurement Manual, U.S. Department of Interior, Bureau of Reclamation, Second Edition, Revised Reprint, 1974, 327 pp. https://www.usbr.gov/tsc/techreferences/mands/wmm/index.htm1.3.3. Flow Measurement in Open Channels and Closed Conduits, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 484, October 1977, 982 pp. https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication484v2.pdf CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-3 1.3.3. NPDES Compliance Inspection Manual, Chapter 6 – Flow Measurement, U.S. Environmental Protection Agency (U.S. EPA), Office of Water Enforcement, Publication Number 305-K-17-001, January 2017, 918 pp. https://www.epa.gov/compliance/compliance-inspection-manual-national- pollutant-discharge-elimination-system 1.4. All monitoring instruments and devices used by the Discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. All flow measurement devices shall be calibrated at least once per year to ensure continued accuracy of the devices. 1.5. Monitoring results, including noncompliance, shall be reported at intervals and in a manner specified in this MRP. 1.6. Unless otherwise specified by this MRP, all monitoring shall be conducted according to test procedures established at 40 C.F.R. part 136, Guidelines Establishing Test Procedures for Analysis of Pollutants. All analyses shall be conducted using the lowest practical quantitation limit achievable using the specified methodology. Where effluent limitations are set below the lowest achievable quantitation limits, pollutants not detected at the lowest practical quantitation limits will be considered in compliance with effluent limitations. Analysis for toxic pollutants listed by the California Toxics Rule shall also adhere to guidance and requirements contained in the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (2005) (SIP). 1.7. The Discharger shall ensure that the results of the Discharge Monitoring Report- Quality Assurance (DMR-QA) Study or the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board at the following address: State Water Resources Control Board; Quality Assurance Program Officer; Office of Information Management and Analysis; 1001 I Street, Sacramento, CA 95814 2. MONITORING LOCATIONS The Discharger shall establish the following monitoring locations to demonstrate compliance with the effluent limitations, discharge specifications, and other requirements in this Order: Table E-1. Monitoring Station Locations Discharge Point Name Monitoring Location Name Monitoring Location Description INF-001 Influent wastewater prior to treatment and following all significant inputs to the collection system of untreated wastewater and inflow and infiltration, where representative samples of CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-4 Discharge Point Name Monitoring Location Name Monitoring Location Description wastewater influent can be obtained prior to any plant return flows or treatment processes EFF-001 EFF-001A At a point where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to entering the discharge pipeline to San Luis Obispo Creek EFF-001B At a point at the end of the discharge pipeline where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to commingling with other waste streams or being discharged into San Luis Obispo Creek EFF-002 EFF-002 Location where a representative sample of title 22 recycled water can be collected prior to discharge to the recycled water storage tank. Receiving Water RSW-001 At Fox Canyon Road Receiving Water RSW-002 At Mission Receiving Water RSW-003 At Marsh Street Bridge Receiving Water RSW-004 50 feet upstream of effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-005 A location in San Luis Obispo Creek immediately upstream of the confluence with Prefumo Canyon Creek CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-5 Discharge Point Name Monitoring Location Name Monitoring Location Description Receiving Water RSW-006 A location in Prefumo Canyon Creek 50 feet upstream of the confluence with San Luis Obispo Creek Receiving Water RSW-007 Approximately 0.5 miles downstream from effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-008 At Higuera Street Bridge, near US 101 Biosolids BIO-001 Biosolids at the last point in the biosolids handling process where representative samples of residual solids from the treatment process can be obtained 3. INFLUENT MONITORING REQUIREMENTS 3.1. Monitoring Location INF-001 3.1.1. The Discharger shall monitor influent to the facility at INF-001 as below: Table E-2. Influent Monitoring Parameter Units Sample Type Minimum Sampling Frequency Flow Million gallons per day (MGD) Measured 1/Day Biochemical Oxygen Demand 5-day @ 20°C (BOD5)[2] Milligram per liter (mg/L) 24-hour Composite 1/Month[1] Total Suspended Solids (TSS)[2] mg/L 24-hour Composite 1/Month[1] [1] The Discharger shall report the average and maximum daily flows. [2] Collection of BOD5 and TSS samples shall occur on days that effluent samples are collected. BOD shall be monitored in the influent at the same time as it is monitored in the effluent. 4. EFFLUENT MONITORING REQUIREMENTS 4.1. Monitoring Location EFF-001 4.1.1. The Discharger shall monitor effluent discharged at Monitoring Location EFF-001 as specified in Table E-3. Except where specified, all monitoring will be performed at EFF-001A. If more than one analytical test method is listed for a given CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-6 parameter, the Discharger must select from the listed methods and corresponding Minimum Level: Table E-3. Effluent Monitoring at EFF-001 Parameter Units Sample Type Minimum Sampling Frequency Flow MGD Metered 1/Day Instantaneous Maximum Flow MGD Metered 1/Day Maximum Daily Flow Calculated 1/Month Mean Daily Flow MGD Calculated 1/Month Biochemical Oxygen Demand, 5- day (BOD5) mg/L 24-hour Composite 1/Month BOD Mass Emissions Rate pounds per day (lbs/day) Calculated 1/Month BOD5 Percent removal Calculated 1/Month pH[1] standard units Continuous or Grab 1/Day Chlorine, Total Residual[2] mg/L Continuous or Grab Grab samples shall be taken a minimum of twice per day, and within 30 minutes of any excursion above 0.1 mg/L Chlorine Used[2] lbs/day Calculated 1/Day Temperature[1] °C Continuous or Grab 5/Week Total Coliform MPN/100 mL Grab 5/Week Settleable Solids milliliter per liter (ml/L) Grab 1/Week Ammonia (as N) mg/L Grab 1/Week Un-ionized Ammonia (as N) [1] mg/L Calculated 1/Week Total Suspended Solids (TSS) mg/L 24-hr. composite 1/Week TSS Percent removal Calculated 1/Week Turbidity Nephelo- metric Turbidity 24-hr. composite 1/10 days CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-7 Parameter Units Sample Type Minimum Sampling Frequency Units (NTU) Dissolved Oxygen mg/L Grab 1/Month Color Color units Grab 1/Month Oil and Grease mg/L Grab 1/Month Total Kjeldahl Nitrogen (TKN) (as N) mg/L Grab 1/Month Chlorodibromomethane (aka Dibromochloromethane) μg/L 24-hr. composite 1/Month[3] Chloroform μg/L 24-hr. composite 1/Month Dichlorobromomethane μg/L 24-hr. composite 1/Month[3] Methylene Chloride μg/L 24-hr. composite 1/Month Pentachlorophenol μg/L 24-hr. composite 1/Month Nitrate (as N) mg/L Grab 1/Month Nitrite (as N) mg/L Grab 1/Month Methylene Blue Active Substances (MBAS) mg/L 24-hr. composite 1/Month Molybdenum mg/L Grab 1/Month Dissolved Orthophosphate (as P) mg/L Grab 1/Month Total Phosphate (as P) mg/L Grab 1/Month Total Dissolved Solids (TDS)[2] mg/L Grab 1/Month Sodium mg/L Grab 1/Month Chloride mg/L Grab 1/Month Sulfate mg/L Grab 1/Month Hardness (CaCO3)[4] mg/L 24-hr. composite 1/Quarter Boron mg/L Grab 1/Year (in October) Cobalt mg/L Grab 1/Year (in October) Iron mg/L Grab 1/Year (in October) Lithium mg/L Grab 1/Year (in October) Manganese mg/L Grab 1/Year (in October) Vanadium mg/L Grab 1/Year (in October) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-8 Parameter Units Sample Type Minimum Sampling Frequency Acute Toxicity[5] ”Pass/Fail” and % Effect Grab 1/Year Chronic Toxicity[5] “Pass/Fail and % Effect” Grab 1/Month[6] California Toxics Rule (CTR) Pollutants[7], [8] μg/L 24-Hour composite 1/Year (in October) Title 22 Pollutants[9], [10] μg/L 24-Hour composite 1/Year (in October) [1] Temperature and pH are to be measured at the same time the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] If no exceedances of the effluent limitation occur for a minimum of 12 consecutive months of monitoring then the frequency of monitoring shall be reduced to quarterly. Subsequently, if an exceedance of the effluent limitation occurs during quarterly monitoring, the monitoring frequency shall return to monthly. The Discharger must notify the Central Coast Water Board of the change in monitoring frequency. [4] Hardness monitoring will occur on the same day and time as the California Toxics Rule (CTR) pollutants to allow for conversion from total recoverable to dissolved for hardness dependent metals. [5] Whole effluent acute and chronic toxicity monitoring shall be conducted according to the requirements established in sections 5.1 and 5.2, respectively, of this MRP. [6] Once per year, in October, chronic toxicity monitoring must be performed at EFF- 001B instead of at EFF-001A. [7] The California Toxics Rule (CTR) pollutants are those listed by the CTR at 40 C.F.R. 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). The Discharger shall instruct its analytical laboratory to establish calibration standards so that the Minimum Levels (MLs) presented in Appendix 4 of the SIP are the lowest calibration standards. The Discharger and its analytical laboratory shall select MLs which are below applicable water quality criteria of the CTR; and when applicable water quality criteria are below all MLs, the Discharger and its analytical laboratory shall select the lowest ML. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-9 [8] Monitoring for the CTR pollutants in effluent shall occur simultaneously with monitoring required for the CTR pollutants in receiving water. [9] The title 22 pollutants are those pollutants for which Maximum Contaminant Levels (MCLs) have been established at title 22, division 4, chapter 15, sections 64431 (inorganic chemicals) and 64444 (organic chemicals) of the California Code of Regulations. Where these pollutants are included in other groups of pollutants (CTR Priority Pollutants), monitoring does not need to be duplicated. Analytical methods shall adhere to the Detection Limits for Purposes of Reporting (DLRs) established by title 22 of the California Code of Regulations, division 4, chapter 15, sections 64432 and 64445.1. [10] Monitoring for the title 22 pollutants in effluent shall occur simultaneously with monitoring required for the title 22 pollutants in receiving water. 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS 5.1. Whole Effluent Acute Toxicity Testing 5.1.1. Routine Acute Toxicity Monitoring Frequency. The Discharger shall conduct at least one acute aquatic toxicity test using the most sensitive species every calendar year during which there is expected to be at least 15 days of discharge in at least one calendar quarter. For the purposes of acute toxicity, the calendar year starts from the initiation of routine monitoring. If the Discharger is unable to sample within the calendar year due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar year was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. 5.1.2. Discharge In-stream Waste Concentration (IWC) for Acute Toxicity. The IWC for this discharge is 100 percent effluent. 5.1.3. Most Sensitive Species. The test species used for acute toxicity testing shall be the most sensitive species. To be consistent with previous Order R3-2014-0033, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct acute toxicity testing from the effective date of this permit until the completion of the required acute species sensitivity screening detailed in section 5.1.6 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation, and the Central Coast Water Board determines that the CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-10 Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.1.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.1.5. Acute Freshwater Species and Test Methods. The Discharger shall conduct acute toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136). Approved tests methods for acute toxicity are listed in Table E-4 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-4. Approved Test for Acute Toxicity – Fresh Water Species Effect Test Duration (hours) Test Method Fathead Minnow (Pimephales promelas) Survival 24, 48, or 96 Survival Test Method 2000.0 Water Flea (Ceriodaphnia dubia) Survival 24, 48, or 96 Survival Test Method 2002.0 5.1.6. Acute Species Sensitivity Screening. The Discharger shall conduct one species sensitivity screening test during the Order’s first required sample collection for acute toxicity. The Discharger shall collect a single effluent sample to initiate and concurrently conduct two toxicity tests using the fish and invertebrate species referenced in Table E-4 above. This sample shall also be analyzed for the parameter(s) required on a monthly and quarterly frequency in Table E-3, during that given month. Samples for the species sensitivity screening shall be analyzed using the TST approach. The species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-11 than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. 5.1.7. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.1.7.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent Effect” for acute toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.80 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.1.7.2. If the effluent toxicity test does not meet all test acceptability criteria (TAC) specified in the referenced test method, Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136) then the Discharger must resample and re-test within 7 days. 5.1.7.3. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.1.7.4. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.1.8. Notification. The Discharger shall notify the Central Coast Water Board of an exceedance of the acute toxicity trigger of 90 percent survival as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-12 Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.1.9. Accelerated Monitoring Requirements. If the result of any acute toxicity test fails to meet the single test minimum trigger (70 percent survival), and the testing meets all TAC, the Discharger shall take two more samples, one within 14 days and one within 21 days following receipt of the initial sample result. If any one of the additional samples do not comply with the three-sample median minimum limitation (90 percent survival), the Discharger shall initiate a Toxicity Reduction Evaluation (TRE) in accordance with section 5.4 of the MRP. If the two additional samples are in compliance with the acute toxicity requirement and testing meets all TAC, then a TRE will not be required. 5.1.10. Reporting. The Self-Monitoring Report (SMR) shall include a full laboratory report for each toxicity test (WET report). The WET report shall be prepared using the format and content of section 12 (Report Preparation) of Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 5th edition or subsequent editions), including: 5.1.10.1. The toxicity test results in percent (%) survival for the 100 percent effluent sample. 5.1.10.2. The toxicity test results for the TST approach, reported as “Pass” or “Fail” and “Percent Effect” at the acute toxicity IWC for the discharge. 5.1.10.3. Water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.1.10.4. TRE/Toxicity Identification Evaluation (TIE) results. The Executive Officer shall be notified no later than 30 days from completion of each aspect of TRE/TIE analyses. 5.1.10.5. Statistical program (e.g., TST calculator, CETIS, etc.) output results for each toxicity test. 5.2. Chronic Toxicity Monitoring Requirements – Monitoring Location EFF-001 5.2.1. Routine Chronic Toxicity Monitoring Frequency. The Discharger shall conduct at least one chronic aquatic toxicity test every calendar month during which there is expected to be at least 15 days of discharge. Initiation of the routine monitoring test shall be at a time that would allow any required Median Monthly Effluent Limitation (MMEL) compliance tests to be initiated within the same calendar month as the routine monitoring test. For routine chronic toxicity monitoring, the Discharger shall conduct at least one chronic toxicity test using the most sensitive species each calendar month during which there is expected to be at least 15 days of discharge. For the purposes of chronic toxicity, the calendar month starts from the initiation of routine monitoring. The Discharger shall ensure there is sufficient time to perform the MMEL compliance testing within the defined calendar month, should the initial toxicity test result in a “Fail”. If the Discharger is unable to sample within the calendar CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-13 month due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar month was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. The Discharger may request to reduce the monitoring frequency from once per calendar month to once per calendar quarter if all of the following conditions are met: 1) the toxicity requirements in this permit have been followed; and 2) there were no violations of the MMEL or Maximum Daily Effluent Limitation (MDEL) for chronic toxicity within the last five years. If a chronic toxicity test results in a “Fail” at the IWC during reduced monitoring, the frequency is automatically increased back to once per month for a period of five years. 5.2.2. Discharge In-stream Waste Concentration (IWC). The IWC for this discharge is 100 percent effluent. 5.2.3. Most Sensitive Species. The test species used for chronic toxicity testing shall be the most sensitive species. To be consistent with Order No. R3-2014-003, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct chronic toxicity testing from the effective date of this permit until the completion of the required chronic species sensitivity screening described in section 5.2.7 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation and the Central Coast Water Board determines that the Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.2.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.2.5. Chronic Freshwater Species and Test Methods. The Discharger shall conduct chronic toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002; Table IA, 40 C.F.R. part 136). Approved CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-14 tests methods for chronic toxicity are listed in Table E-5 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-5. Approved Tests for Chronic Toxicity – Freshwater Species Effect Test Duration (days) Test Method Fathead Minnow (Pimephales promelas) Larval Survival and Growth 7 Larval Survival and Growth Test Method 1000.0 Water Flea (Ceriodaphnia dubia) Survival and Reproduction 6 to 8 days Survival and Reproduction Test Method 1002.0 Green Alga (Selenastrum capricornutum) Growth 4 days Growth Test Method 1003.0 5.2.6. Median Monthly Effluent Limitation (MMEL) Compliance Monitoring. If a chronic toxicity test conducted during routine monitoring results in a “Fail” at the IWC, the Discharger shall conduct a maximum of two chronic toxicity MMEL compliance tests. The MMEL compliance tests shall be initiated within the same calendar month that the first routine chronic toxicity test was initiated that resulted in a “Fail” at the IWC. If the first chronic toxicity MMEL compliance test results in a “Fail” at the IWC, then the second chronic toxicity MMEL compliance test is not required. 5.2.7. Chronic Species Sensitivity Screening. The Discharger shall conduct four species sensitivity screening tests within 18 months of the effective date of this permit and four species sensitivity screening tests within one year of submitting the ROWD for the Facility, with one set of screenings conducted in each quarter for four consecutive quarters. For each set of species sensitivity screenings, the Discharger shall collect a single effluent sample to initiate and concurrently conduct three toxicity tests using the fish, invertebrate, and alga species referenced in Table E-5 above. This sample shall also be analyzed for the parameter(s) required on a monthly and quarterly frequency in Table E-3, during that given month. As allowed under the test method for the Ceriodaphnia dubia and the Pimephales promelas, a second and third sample shall be collected for use as test solution renewal water as the seven-day toxicity test progresses. Samples for the species sensitivity screening shall be analyzed using the TST approach. After the fourth set of species sensitivity screening, the species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-15 repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. During the calendar month, toxicity tests used to determine the most sensitive test species shall be reported as effluent compliance monitoring results for the MDEL and MMEL for chronic toxicity. 5.2.8. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.2.8.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent (%) Effect” for chronic toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.2.8.2. The MDEL for chronic toxicity is exceeded and a violation will be flagged when a toxicity test during routine monitoring results in “Fail” for the sub-lethal endpoint in accordance with the TST approach and the “Percent Effect” is greater than or equal to 50 percent for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. 5.2.8.3. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. 5.2.8.4. If the effluent toxicity test does not meet all TAC specified in the referenced test method, Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002) then the Discharger must resample and re-test within 14 days. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-16 5.2.8.5. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.2.8.6. Monthly reference toxicant testing is sufficient if in accordance with Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). All reference toxicant test results should be reviewed and reported using the effects concentration at 25 percent (EC25). 5.2.8.7. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.2.9. Notification. The Discharger shall notify the Central Coast Water Board of a violation of a toxicity MDEL or MMEL as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.2.10. Routine Reporting. The SMR shall include a full laboratory report for each chronic toxicity test. This report shall be prepared using the format and content of the test methods manual in section 10 of Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002), Report Preparation, and shall include: 5.2.10.1. The valid toxicity test results for the TST statistical approach, reported as “Pass” or “Fail” and “Percent Effect” at the chronic toxicity IWC for the discharge. All toxicity test results (whether identified as valid or otherwise) conducted during the calendar month shall be reported on the SMR due date specified in Table E-11. 5.2.10.2. Summary water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.2.10.3. The statistical analysis used in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10- 003, 2010) Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. 5.2.10.4. Statistical program (e.g., TST calculator, CETIS, etc.) output results, including graphical plots, for each toxicity test. 5.2.10.5. Tabular data and graphical plots clearly showing the laboratory’s performance for the reference toxicant for the previous 20 tests and the laboratory’s performance for the control mean, control standard deviation, and control coefficient of variation for the previous 12-month period. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-17 5.2.10.6. Any additional quality assurance/quality control (QA/QC) documentation or any additional chronic toxicity-related information, upon written request from the Central Coast Water Board. 5.3. Accelerated Monitoring Requirements 5.3.1. When acute toxicity is detected in the effluent, or when the chronic toxicity effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all TAC, the Discharger shall initiate accelerated monitoring to confirm the effluent toxicity. 5.3.2. The Discharger shall implement an accelerated monitoring frequency consisting of performing three toxicity tests in a six-week period following the first failed test results. 5.3.3. If implementation of the generic Toxicity Reduction Evaluation (TRE) Work Plan indicates the source of the exceedance of the effluent limitation or toxicity trigger (for instance, a temporary plant upset), then only one additional test is necessary. If exceedance of the effluent limitation or toxicity trigger is detected in this test, the Discharger will continue with accelerated monitoring requirements or implement the Toxicity Identification and Toxicity Reduction Evaluations. 5.3.4. If none of the three tests indicated exceedance of the effluent limitation or toxicity trigger, then the Discharger may return to the normal testing frequency. 5.4. Toxicity Identification Evaluations (TIE) and Toxicity Reduction Evaluation (TRE) Process 5.4.1. A TIE shall be triggered if testing from the accelerated monitoring frequency indicates any of the following: 5.4.1.1. Two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. 5.4.1.2. The TIE shall be initiated within 15 days following failure of the second accelerated monitoring test. 5.4.1.3. If a TIE is triggered prior to the completion of the accelerated testing, the accelerated testing schedule may be terminated, or used as necessary in performing the TIE. 5.4.2. The TIE shall be conducted to identify and evaluate toxicity in accordance with procedures recommended by the U.S. EPA, which include the following: 5.4.2.1. Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents, Phase I, (U.S. EPA, 1992a); 5.4.2.2. Methods for Aquatic Toxicity Identification Evaluations: Phase I Toxicity Characterization Procedures, Second Edition (U.S. EPA, 1991a); 5.4.2.3. Methods for Aquatic Toxicity Identification Evaluations: Phase II Toxicity Identification Procedures for Sampling Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993a); and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-18 5.4.2.4. Methods for Aquatic Toxicity Identification Evaluations: Phase III Toxicity Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993b). 5.4.3. As part of the TIE investigation, the Discharger shall be required to implement its TRE Work Plan. The Discharger shall take all reasonable steps to control toxicity once the source of the toxicity is identified. A failure to conduct required toxicity tests or a TRE within a designated period shall result appropriate enforcement action. Recommended guidance in conducting a TRE includes the following: 5.4.3.1. Toxicity Reduction Evaluation Guidance for Municipal Wastewater Treatment Plants, August 1999, EPA/833B-99/002; and 5.4.3.2. Clarifications Regarding Toxicity Reduction and Identification Evaluations in the National Pollutant Discharge Elimination System Program dated March 27, 2001, U.S. EPA Office of Wastewater Management, Office of Regulatory Enforcement. 5.4.4. The Central Coast Water Board may also require the Discharger conduct a TRE if other information indicates toxicity (e.g., results of additional monitoring, results of monitoring at a higher concentration than the IWC, fish kills, intermittent recurring toxicity), or if there is no effluent available to complete routine monitoring, a MMET test or a MMEL Compliance Test. 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable 7. RECYCLING MONITORING REQUIREMENTS 7.1. Monitoring Location RCY-001 7.1.1. The Discharger shall monitor recycled water at Monitoring Location RCY-001 as described below: Table E-6. Recycled Water Monitoring Requirements at RCY-001 Parameter Units Sample Type Minimum Sampling Frequency[3] Daily Flow MGD Metered Continuous Total Coliform MPN/100 mL Grab 1/Day Turbidity[1] NTU Metered Continuous pH standard units Grab 1/Day Total Chlorine Residual[2] mg/L Metered Continuous [1] Turbidity to be sampled immediately downstream of the membrane bioreactors. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-19 the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] Monitoring is not required during periods recycled water is not being produced for use outside of the Facility. The Discharger shall specify within the SMR if production of recycled water took place during the monitoring period. 7.1.2. In the event the Producer is unable to comply with the conditions of the water recycling requirements and prohibitions, the Producer shall immediately notify the Central Coast Water Board by telephone and submit a written follow-up report with two weeks of the noncompliance. The written report shall include pertinent information explaining reasons for the noncompliance and shall indicate what steps are being taken to prevent the problems from recurring. 7.1.3. An annual self-monitoring report shall be submitted to the Central Coast Water Board by April 1 of the following year. The report shall include the following: 7.1.3.1. A letter transmitting self-monitoring reports shall accompany each report. The letter shall include a discussion of violations found during the reporting period and actions taken or planned for correcting noted violations, such as operation or facility modifications. If the Producer has previously submitted a report describing corrective actions or a time schedule for implementing corrective actions, reference to the previous correspondence will be satisfactory. The transmittal letter shall contain a statement by the Producer or the Producer’s authorized agent, under penalty of perjury, that to the best of the signer’s knowledge the report is true, accurate, and complete. 7.1.3.2. Tabulations of the results of each required analysis by the Producer specified in Table E-6 by date, time, type of sample, and station. 8. RECEIVING WATER MONITORING REQUIREMENTS 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW-008 8.1.1. The Discharger shall monitor the receiving water at Monitoring Locations RSW- 001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW- 008 as follows: Table E-7. Receiving Water Monitoring Requirements Parameter Units Sample Type [1] Sampling Station Minimum Sampling Frequency Flow[2] CFS Instantaneous 4, 5, 7, 8 1/Month Flow MGD Estimated 4, 5, 7, 8 1/Month[3] Turbidity[2] NTU Grab 4, 5, 1/Month Color[2] Color units Grab 4, 5 1/Month CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-20 Parameter Units Sample Type [1] Sampling Station Minimum Sampling Frequency pH[2] standard units (s.u.) Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Temperature °C Grab 4, 5 1/Month Un-ionized Ammonia (as N) [4] mg/L Calculated 4, 5 1/Month Nitrate (as N) mg/L Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Total Phosphate (as P) mg/L Grab 5, 7, 8 1/Month Algal Description Visual observatio n Grab 5, 7, 8 1/Month Ammonia, Total (as N) mg/L Grab 5, 7, 8 1/Month Total Kjeldahl Nitrogen (as N) mg/L Grab 5, 7, 8 1/Month Total Dissolved Solids (TDS) mg/L Grab 4, 5, 7, 8 1/Month Chloride mg/L Grab 4, 5, 7, 8 1/Month Sulfate mg/L Grab 4, 5, 7, 8 1/Month Sodium mg/L Grab 4, 5, 7, 8 1/Quarter Boron mg/L Grab 4, 5, 7, 8 1/Quarter Hardness, as CaCO3 mg/L Grab 4, 5, 7, 8 1/Quarter Molybdenum mg/L Grab 4, 5, 7, 8 1/Year Methylene Blue Activated Substances mg/L Grab 4, 5, 7, 8 1/Year E. coli MPN/100 mL Grab 4, 5, 7, 8 1/Quarter CTR Pollutants[6], [7] µg/L Grab 4, 5 1/Year Title 22 Pollutants[8], [9] µg/L Grab 4, 5 1/Year [1] Samples shall be obtained only when safe to do so. [2] The San Luis Obispo Creek flow rate shall be used to determine the upstream and downstream stations where these constituents shall be monitored as follows: If the creek flows underground between Monitoring Location RSW-002 and the discharge point, samples shall be obtained from Monitoring Locations RSW-002. If the creek flows aboveground from Monitoring Location RSW-002 to the discharge point, samples shall be obtained from Monitoring Location RSW-004. In eater case, Monitoring Location RSW-005 shall be the downstream location. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-21 [3] Sampling shall be concurrent with sampling of effluent for ammonia. [4] Temperature and pH are to be measured at the same time that the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [5] Narrative description of algae present at the monitoring location shall include: algal color, location with respect to stream banks and depth of water, and appearance (filamentous, matting, attached, etc. percent coverage of water surface). [6] The CTR pollutants are those listed by the CTR at 40 CFR 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). [7] Monitoring of receiving water for the CTR pollutants shall occur simultaneously with effluent monitoring for the CTR pollutants. [8] The title 22 pollutants are those for which primary MCLs have been established and which are listed in sections 64431-A and 64444-A of the California Code of Regulations, title 22, division 4, chapter 15. Where these pollutants are also identified as CTR Priority Pollutants, monitoring does not need to be duplicated. [9] Monitoring of receiving water for the title 22 Pollutants shall occur simultaneously with effluent monitoring for title 22 pollutants. 9. OTHER MONITORING REQUIREMENTS 9.1. Biosolids, Monitoring, and Notification – BIO-001 9.1.1. A representative sample of biosolids shall be obtained from the last point in the handling process (i.e., in the drying beds just prior to removal or from a pond bottom). All constituents shall be analyzed annually for total concentrations for comparison with Total Threshold Limit Concentration (TTLC) criteria. The Waste Extraction Test shall be performed on any constituent when the total concentration of the waste exceeds ten times the Soluble Threshold Limit Concentration (STLC) for that substance. Twelve (12) discrete representative samples shall be collected at separate locations in the biosolids ready for disposal. These 12 samples shall be composited to form one (1) sample for constituent analysis. For accumulated, previously untested biosolids, the Discharger shall develop a representative sampling plan including number and location of sampling points and collect representative samples. The analysis shall test for the metals required in 40 C.F.R. 503.16 (for land application) or 503.26 (for surface disposal), using the methods in Test Methods for Evaluating Solid Waste, Physical/Chemical Methods (U.S. EPA Publication SW-846, all applicable editions and updates), as required in 503.8(b)(4), at the minimum frequencies established therein, provided in the table below. Table E-8. Amount of Biosolids and Frequency of Analysis CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-22 Amount[1] (dry metric tons/365-day period) Minimum Sampling Frequency[2] Greater than zero, but less than 290 Once per year Equal to or greater than 290 but less than 1,500 Once per quarter (four times per year) Equal to or greater than 1,500 but less than 15,000 Once per sixty days (six times per year) Greater than 15,000 Once per month (twelve times per year) [1] For land application, either the amount of bulk biosolids applied to the land or the amount prepared for sale or give-away in a bag or other container for application to the land (dry weight basis). If the Discharger’s biosolids are directly land applied without further treatment by another preparer, biosolids shall also be tested for organic-N, ammonium-N, and nitrate-N at the frequencies required. For surface disposal, the amount of biosolids placed on an active sludge unit (dry weight basis). [2] Test results shall be expressed in mg pollutant per kg biosolids on a 100% dry weight basis. With U.S. EPA approval the amount of biosolids and minimum sampling frequency can coincide with the testing regiment implemented for Cal recycle. Biosolids shall be analyzed for the constituents in the table below. Table E-9. Biosolids Monitoring Requirements Parameter Units Sample Type Minimum Sampling Frequency Quantity Removed Tons or yd3 Measured During Removal Location of Reuse/Disposal General Public or Specific Site -- -- Moisture Content Percent Grab Per Table E-8 (above) pH standard units Grab Per Table E-8 (above) Total Kjeldahl Nitrogen mg/kg[1] Grab Per Table E-8 (above) Ammonia (as N) mg/kg[1] Grab Per Table E-8 (above) Nitrite (as N) mg/kg[1] Grab Per Table E-8 (above) Total Phosphorus mg/kg[1] Grab Per Table E-8 (above) Oil and Grease mg/kg[1] Grab Per Table E-8 (above) Arsenic mg/kg[1] Grab Per Table E-8 (above) Boron mg/kg[1] Grab Per Table E-8 (above) Cadmium mg/kg[1] Grab Per Table E-8 (above) Copper mg/kg[1] Grab Per Table E-8 (above) Chromium (Total) mg/kg[1] Grab Per Table E-8 (above) Lead mg/kg[1] Grab Per Table E-8 (above) Mercury mg/kg[1] Grab Per Table E-8 (above) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-23 Parameter Units Sample Type Minimum Sampling Frequency Molybdenum mg/kg[1] Grab Per Table E-8 (above) Nickel mg/kg[1] Grab Per Table E-8 (above) Selenium mg/kg[1] Grab Per Table E-8 (above) Zinc mg/kg[1] Grab Per Table E-8 (above) [1] Total sample (including solids and any liquid portion) to be analyzed and results reported as mg/kg based on the dry weight of the sample. 9.1.2. Prior to land application, the Discharger shall demonstrate that the biosolids meet Class A or Class B pathogen reduction levels by one of the methods listed in 40 C.F.R. 503.32 (unless transferred to another preparer who demonstrates pathogen reduction). Prior to disposal in a surface disposal site, the Discharger shall demonstrate that the biosolids meet Class B levels or shall ensure that the site is covered at the end of each operating day. If pathogen reduction is demonstrated using a “Process to Significantly/Further Reduce Pathogens “(PFRP), the Discharger shall maintain daily records of the operating parameters to achieve this reduction. The following applies when biosolids from the Discharger are directly land applied as Class B, without further treatment by a second preparer. If the Discharger demonstrates pathogen reduction by direct testing for fecal coliforms and/or pathogens, samples must be drawn at the frequency in the Amount/Frequency table above. If the Discharger demonstrates Class B pathogen reduction by testing for fecal coliform, at least seven grab samples must be drawn and analyzed during each monitoring event, and a geometric mean calculated from these seven samples. If the Discharger demonstrates Class A pathogen reduction by testing for fecal coliform and/or salmonella, plus one of the PFRP processes or testing for enteric viruses and helminth ova at least four samples of fecal coliform or salmonella must be drawn during each monitoring event. All four samples must meet the limits specified in 503.32(a). 9.1.3. For biosolids that are land applied or placed in a surface disposal site, the Discharger shall track and keep records of the operational parameters used to achieve Vector Attraction Reduction requirements in 40 C.F.R. 503.33(b). 9.1.4. Class 1 facilities (facilities with pretreatment programs or others designated as Class 1 by the Regional Administrator) and federal facilities with greater than five million gallons per day (MGD) influent flow shall sample biosolids for pollutants listed under CWA section 307(a), as required in the pretreatment section of the permit for Publicly Owned Treatment Works (POTWs) with pretreatment programs. Class 1 facilities and federal facilities greater than 5 MGD shall test dioxins/dibenzofurans using a detection limit of less than one pg/g at the time of their next priority pollutant scan if they have not done so within the past five years, and once per five years thereafter. 9.1.5. The biosolids shall be tested annually, or more frequently if necessary, to determine hazardousness. All constituents regulated under title 22 California CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-24 Code or Regulations, division 5, chapter 11, article 3 shall be analyzed for comparison with TTLC criteria. The waste extraction test shall be performed on any constituent when the total concentration of the waste exceeds ten times the STLC limit for that substance. 9.1.6. If biosolids are placed in a surface disposal site (dedicated land disposal site or monofill), a qualified groundwater scientist shall develop a groundwater monitoring program for the site, or shall certify that the placement of biosolids on the site will not contaminate an aquifer. 9.1.7. Biosolids placed in a municipal landfill shall be tested by the Paint Filter Liquids Test (U.S. EPA Method 9095) at the frequency determined by Table E-9, or more often if necessary, to demonstrate that there are no free liquids. 9.1.8. The Discharger, either directly or through contractual agreements with their biosolids management contractors, shall comply with the following notification requirements: 9.1.8.1. Notification of non-compliance. The Discharger shall notify U.S. EPA Region 9, the State Water Board, and the Regional Water Board located in the region where the biosolids are used or disposed, of any non-compliance within 24 hours if the noncompliance may seriously endanger health or the environment. For other instances of non-compliance, the Discharger shall notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance in writing within five working days of becoming aware of the non-compliance. The Discharger shall require their biosolids management contractors to notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance within the same time frames. 9.1.8.2. If biosolids are shipped to another state or Native American lands, the Discharger must send notice at least 60 days prior to the shipment to the permitting authorities in the receiving state or Native American land (the U.S. EPA Regional Office for that area and the State/Native American authorities). 9.1.8.3. For land application (in cases where Class B biosolids are directly applied without further treatment): Prior to reuse of any biosolids from the Discharger’s facility to a new or previously unreported site, the Discharger shall notify U.S. EPA, the Central Coast Water Board, and any other affected Regional Water Board. The notification shall include description of the crops or vegetation to be grown, proposed loading rates and determination of agronomic rates. If any biosolids within a given monitoring period do not meet 40 C.F.R. 503.13 metals concentrations limits, the Discharger (or its contractor) must pre-notify U.S. EPA, and determine the cumulative metals loading to that site to date, as required in 40 C.F.R. 503.12. The Discharger shall notify the applier of all the applier’s requirements under 40 C.F.R. part 503, including the requirement that the applier certify that the management practices, site restrictions, and any applicable vector attraction reduction requirements have been met. The Discharger shall require the applier to certify at the end of 38 months following CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-25 application of Class B biosolids that the harvesting restrictions in effect for up to 38 months have been met. 9.1.8.4. For surface disposal: Prior to disposal to a new or previously unreported site, the Discharger shall notify U.S. EPA and the Central Coast Water Board. The notice shall include a description and a topographic map of the proposed site, depth to ground water, whether the site is lined or unlined, site operator, site owner, and any State or local permits. The notice shall describe procedures for ensuring public access and grazing restrictions for three years following site closure. The notice shall include a ground water monitoring plan or description of why ground water monitoring is not required. 9.1.9. The Discharger shall submit an annual biosolids report to the U.S. EPA Region 9 Biosolids Coordinator and Central Coast Water Board by February 19th of each year (per U.S. EPA guidance and 40 C.F.R. part 503) for the period covering the previous calendar year. This report shall include: 9.1.9.1. Annual biosolids removed in dry tons and percent solids. 9.1.9.2. If appropriate, a narrative description of biosolids dewatering and other treatment processes, including process parameters, including a schematic diagram showing biosolids handling facilities. For example, if drying beds are used, report depth of application and drying time. If composting is used, report the temperature achieved and duration. 9.1.9.3. A description of disposal methods, including the following information as applicable related to the disposal methods used at the facility. If more than one method is used, include the percentage and tonnage of annual biosolids production disposed by each method. 9.1.9.3.1. For landfill disposal include: 1) the Regional Water Board waste discharge requirement (WDR) numbers that regulate the landfills used, 2) the present classifications of the landfills used, 3) the results of any ground water monitoring, 4) certifications of management practices, and 5) the names and locations of the facilities receiving biosolids. 9.1.9.3.2. For land application include: 1) the location of the site(s), 2) the Regional Water Board's WDR numbers that regulate the site(s), 3) the application rate in lbs/acre/year (specify wet or dry), 4) certifications of management practices and site restrictions, and 5) subsequent uses of the land. 9.1.9.3.3. For offsite application by a licensed hauler and composter include: 1) the name, address and U.S. EPA license number of the hauler and composter. 9.1.9.4. Copies of analytical data required by other agencies (i.e. U.S. EPA or County Health Department) and licensed disposal facilities (i.e. landfill, land application, or composting facility) for the previous year. 9.1.9.5. Descriptions of pathogen reduction methods and vector attraction reduction methods. Including supporting time and temperature data, and certifications, as required in 40 C.F.R. 503.17 and 503.27. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-26 9.1.9.6. Names mailing address, and street addresses of persons who received biosolids for storage, further treatment, disposal in a municipal waste landfill, or for other use or disposal methods not covered above, and amounts delivered to each. 9.1.9.7. For all biosolids used or disposed at the Discharger’s facility, the site and management practice information and certification required in 40 C.F.R. 503.17 and 503.27. 9.1.9.8. For all biosolids temporarily stored, the information required in 40 C.F.R. 503.20 is required to demonstrate temporary storage. 9.1.9.9. Reports shall be submitted in electronically using EPA’s Central Data Exchange website at CDX Home | Central Data Exchange | US EPA (cdx.epa.gov). A PDF copy can be printed and sent to: Executive Officer Central Coast Water Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 9.2. Pretreatment Monitoring By February 1 of each year, the Discharger shall submit an Annual Report to the State Water Board, Central Coast Water Board, and U.S. EPA describing the Discharger’s pretreatment activities over the previous 12 months. In the event that the Discharger is not in compliance with any pretreatment condition of this Order or resulting from pretreatment audits or compliance inspections, then the Discharger shall also include the reasons for noncompliance and state how and when the Discharger will comply with such conditions and requirements. This report shall contain, but not be limited to, the following information: 9.2.1. A summary of analytical results from representative, flow-proportioned, 24-hour composite sampling of the plant's effluent and sludge as provided in the relevant sections of this MRP. The Discharger shall also provide any influent, effluent, or sludge monitoring data for nonpriority pollutants which the Discharger believes may be causing or contributing to interference, pass-through, or adversely impacting sludge quality. Sampling and analysis shall be performed in accordance with the techniques prescribed in 40 C.F.R. part 136 and amendments thereto. 9.2.2. A discussion of upset, interference, or pass-through incidents, if any, at the POTW, which the Discharger knows or suspects were caused by industrial users of the POTW system. The discussion shall include the reasons why incidents occurred, corrective actions taken and, if known, the name and address of the industrial user(s), responsible. Discussions shall also include a review of applicable pollutant limitations to determine whether any additional limitations or changes to existing requirements may be necessary to prevent pass-through, interference, or noncompliance with sludge disposal requirements. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-27 9.2.3. The cumulative number of industrial users that the Discharger has notified regarding Baseline Monitoring Reports and the cumulative number of industrial user responses. 9.2.4. An updated list of the Discharger's industrial users, including their names and addresses, or a list of deletions and additions keyed to a previously submitted list. The Discharger shall provide a brief explanation for each deletion. The list shall identify the industrial users subject to Federal Categorical Standards by specifying which set(s) of standards are applicable. The list shall indicate which categorical industries, or specific pollutants from each industry, are subject to local limitations that are more stringent than the Federal Categorical Standards. The Discharger shall also list the non-categorical industrial users that are subject only to local discharge limitations. The Discharger shall characterize the compliance status of each industrial user by employing the following descriptions. 9.2.4.1. In compliance with Baseline Monitoring Report requirements (where applicable); 9.2.4.2. Consistently achieving compliance; 9.2.4.3. Inconsistently achieving compliance; 9.2.4.4. Significantly violated applicable pretreatment requirements defined by 40 C.F.R. 403.8 (f)(2)(vii); 9.2.4.5. On a schedule to achieve compliance (include the date final compliance is required); 9.2.4.6. Not achieving compliance and not on a compliance schedule; or 9.2.4.7. The Discharger does not know the industrial user's compliance status. A report describing the compliance status of any industrial user characterized by descriptions in Items 9.2.4.4.3. through 9.2.4.4.7., above, shall be submitted quarterly from the annual report date to the State Water Board, Central Coast Water Board, and U.S. EPA. The report shall identify the specific compliance status of each such industrial user. This quarterly reporting requirement shall commence upon issuance of this Order. Quarterly reports shall be submitted May 1, August 1, and November 1. The fourth quarter report shall be incorporated in the Annual Report (February 1). Quarterly reports shall briefly describe POTW compliance with audit/pretreatment compliance inspection requirements. If none of the aforementioned conditions exist, at a minimum, a letter indicating that all industries are in compliance and no violations or changes to the pretreatment program have occurred during the quarter must be submitted. 9.2.4.8. A summary of inspection and sampling activities conducted by the Discharger during the past year to gather information and data regarding industrial users. The summary shall include the following: 9.2.4.8.1. Names and addresses of the industrial users subject to surveillance by the Discharger and an explanation of whether they were inspected, sampled, or both and the frequency of these activities at each user; and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-28 9.2.4.8.2. Conclusions or results from the inspection or sampling of each industrial user. 9.2.4.9. A summary of compliance and enforcement activities during the past year. The summary shall include names and addresses of the industrial users affected by the following actions. 9.2.4.9.1. Warning letters or notices of violation regarding the industrial users' apparent noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the apparent violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.2. Administrative Orders regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.3. Civil actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.4. Criminal actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned Federal Categorical Standards or local discharge limitations; 9.2.4.9.5. Assessment of monetary penalties. For each industrial user, identify the amount of the penalties; 9.2.4.9.6. Restriction of flow to the POTW; and 9.2.4.9.7. Disconnection from discharge to the POTW. 9.2.4.10. Description of any significant changes in operating the pretreatment program, which differ from the information in the Discharger's approved POTW Pretreatment Program including, but not limited to, changes concerning: 9.2.4.10.1. The program's administrative structure; 9.2.4.10.2. Local industrial discharge limitations; 9.2.4.10.3. Monitoring program and monitoring frequencies; 9.2.4.10.4. Legal authority or enforcement policy; 9.2.4.10.5. Funding mechanisms; 9.2.4.10.6. Resource requirements; and 9.2.4.10.7. Staffing levels. 9.2.4.11. A summary of the annual pretreatment budget, including costs of pretreatment program functions and equipment purchases. 9.2.4.12. A summary of public participation activities to involve and inform the public. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-29 9.2.4.13. A description of any changes in sludge disposal methods and a discussion of any concerns not described elsewhere in the report. The pretreatment quarterly and annual reports shall be signed by a principal executive officer, ranking elected official, or other duly authorized employee who is responsible for the overall operation of the Discharger (POTW - 40 C.F.R. section 403.12(m)). The Discharger shall submit signed copies of the reports to the State Water Board and the Regional Water Board electronically through the SMR module of CIWQS. Signed copies of the reports shall also be submitted electronically to U.S. EPA at R9Pretreatment@epa.gov or as instructed otherwise. 9.3. Salt and Nutrient Management Plan Reporting The previous Order required the Discharger to develop and implement an ongoing salts management plan dedicated to minimized the discharge of salts to and attainment of applicable water quality objectives (WQOs) for salts in San Luis Obispo Creek sub- basin of the Estero Bay Drainage Basin. Additionally, the previous order required the Discharger to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable WQOs for nutrients in the same basin. Based on the annual reports supplied by the Discharger, over the previous period of the Order, the Discharger has demonstrated that the effluent has contributed to exceedances of 2019 Basin Plan WQOs for salts. By February 1 of each year, the Discharger shall submit an annual report (separate from the NPDES annual report) describing salt and nutrient reduction efforts. The report shall include, at a minimum: 9.3.1. Salt Component 9.3.1.1. Calculations of annual salt mass discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; 9.3.1.2. Analysis of wastewater evaporation/salt concentration effects; 9.3.1.3. Analysis of groundwater monitoring results for salts constituents and associated trends; 9.3.1.4. Analysis of potential impacts of salt loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.1.5. A summary of existing salt reduction measures; and, 9.3.1.6. Recommendations and time schedules for implementation of any additional salt reduction measures. 9.3.2. Nutrient Component 9.3.2.1. Calculations of annual nitrogen mass (for all identified species) discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-30 9.3.2.2. Analysis of wastewater treatment facility ability to facilitate nitrification and denitrification, or other means of nitrogen removal; 9.3.2.3. Analysis of groundwater monitoring results for nitrogen constituents and trends; 9.3.2.4. Analysis of potential impacts of nitrogen loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.2.5. A summary of existing nitrogen loading reduction measures; and, 9.3.2.6. Recommendations and time schedules for implementation of any additional nitrogen loading reduction measures. 9.4. Volumetric Monitoring of Wastewater and Recycled Water 9.4.1. Monthly volume of wastewater collected and treated by the wastewater treatment plant. 9.4.2. Monthly volume of wastewater treated, specifying level of treatment, including treated wastewater discharged. 9.4.3. Monthly volume of treated wastewater discharged, monthly volume of recycled water distributed for reuse, and annual volume of treated wastewater distributed for beneficial use in compliance with California Code of Regulations, title 22 use categories. 9.5 Discharge to Evaporation Ponds 9.5.1. The Discharger shall provide written notification to the Central Coast Water Board when there is any discharge to or from the Facility’s evaporation ponds, which are described in section 2.1 of the Fact Sheet. If the discharge is anticipated, the Discharger shall provide notice within 10 days prior to the anticipated discharge. If the discharge is unanticipated, the Discharger shall provide notice within 24 hours of the time the discharge occurs. Discharge from the evaporation ponds is not permitted in this Order, so standard provision 5.5 applies. The notification must include discharge dates, times, volumes, and reasons for discharge. The notification must be submitted electronically, consistent with standard provision 5.10. 10. REPORTING REQUIREMENTS 10.1. General Monitoring and Reporting Requirements The Discharger shall comply with all Standard Provisions (Attachment D) related to monitoring, reporting, and recordkeeping. 10.2. Self-Monitoring Reports (SMRs) 10.2.1. The Discharger shall electronically submit SMRs using the State Water Board’s California Integrated Water Quality System (CIWQS) Program website (http://www.waterboards.ca.gov/water_issues/programs/ciwqs). The CIWQS CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-31 website will provide additional information for SMR submittal in the event there will be a planned service interruption for electronic submittal. 10.2.2. The Discharger shall report in the SMR the results for all monitoring specified in this MRP under sections 3 through 9. The Discharger shall submit SMRs including the results of all required monitoring using U.S. EPA-approved test methods or other test methods specified in this Order. SMRs are to include all new monitoring results obtained since the last SMR was submitted. If the Discharger monitors any pollutant more frequently than required by this Order, the results of this monitoring shall be included in the calculations and reporting of the data submitted in the SMR. 10.2.3. Monitoring periods and reporting for all required monitoring shall be completed according to the following schedule: Table E-1011. Monitoring Periods and Reporting Schedule SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date NPDES Monitoring Report – Continuous, Daily, Weekly, Monthly MRP Sections 3 (Influent), 4 (Effluent) and 5 (Whole Effluent Toxicity), 9.5 Monthly First day of second calendar month following period of sampling Updated Toxicity Reduction Evaluation Work Plan Permit Section 6.3.2.1.1 Once 90 days following permit NPDES Monitoring Report - Quarterly MRP Sections 4 (Effluent) and 8.1 (Receiving Water) Quarterly May 1st August 1st November 1st February 1st NPDES Monitoring Report – Annually MRP Sections 4 (Effluent) and 8.1 (Receiving Water), 9.5 Annually February 1st Recycled Water Monitoring Report MRP Section 7.1 (Recycled Water Monitoring) Annually April 1st, the year following CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-32 SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date Recycled Water Volumetric Monitoring MRP Section 9.4 (Volumetric Reporting of Wastewater and Recycled Water) Annually April 30th, the year following sampling Note: This report is submitted using the GeoTracker system, not CIWQS Biosolids Monitoring Report MRP Section 9.1 (Biosolids Monitoring) Annually February 19th, the year following sampling Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Quarterly May 1st August 1st November 1st February 1st Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Annually February 1st, the year following sampling Summary Report Attachment D, Standard Provision, 8.4.8 (page D-16) Annually February 15th, the year following Salt and Nutrient Management Plan Annual Report MRP Section 9.3 (Salt and Nutrient Management Plan Reporting) Annually February 1st, the following year Pollutant Minimization Program Annual Permit Section 6.3.3.2 (Pollutant Minimization Program) Annually February 1, the following year Climate Change Implementation Progress Report Permit Section 6.3.6.2 (Climate Change Adaptation Implementation Progress Report) Every five years May 1st, every five years following permit effective date. ROWD Application Permit renewal application Once per permit term 180 days prior to permit expiration date CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-33 10.2.4. Reporting Protocols. The Discharger shall report with each sample result the applicable Reporting Level (RL) and the current Method Detection Limit (MDL), as determined by the procedure in 40 C.F.R. part 136. The Discharger shall report the results of analytical determinations for the presence of chemical constituents in a sample using the following reporting protocols: 10.2.4.1. Sample results greater than or equal to the RL shall be reported as measured by the laboratory (i.e., the measured chemical concentration in the sample). 10.2.4.2. Sample results less than the RL, but greater than or equal to the laboratory’s MDL, shall be reported as “Detected, but Not Quantified,” or DNQ. The estimated chemical concentration of the sample shall also be reported. For the purposes of data collection, the laboratory shall write the estimated chemical concentration next to DNQ. The laboratory may, if such information is available, include numerical estimates of the data quality for the reported result. Numerical estimates of data quality may be percent accuracy (± a percentage of the reported value), numerical ranges (low to high), or any other means considered appropriate by the laboratory. 10.2.4.3. Sample results less than the laboratory’s MDL shall be reported as “Not Detected,” or ND. 10.2.4.4. Dischargers are to instruct laboratories to establish calibration standards so that the ML value (or its equivalent if there is differential treatment of samples relative to calibration standards) is the lowest calibration standard. At no time is the Discharger to use analytical data derived from extrapolation beyond the lowest point of the calibration curve. 10.2.5. Compliance Determination. Compliance with effluent limitations for priority pollutants shall be determined using sample reporting protocols defined above and Attachment A. For purposes of reporting and administrative enforcement by the Central Coast Water Board and State Water Board, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the priority pollutant in the monitoring sample is greater than the effluent limitation and greater than or equal to the reporting level (RL). 10.2.6. Multiple Sample Data. When determining compliance with an AMEL, AWEL, or MDEL for priority pollutants and more than one sample result is available, the Discharger shall compute the arithmetic mean unless the data set contains one or more reported determinations of “Detected, but Not Quantified” (DNQ) or “Not Detected” (ND). In those cases, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 10.2.6.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 10.2.6.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-34 which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 10.2.7. The Discharger shall submit SMRs in accordance with the following requirements: 10.2.7.1. The Discharger shall arrange all reported data in a tabular format. The data shall be summarized to clearly illustrate whether the facility is operating in compliance with interim and/or final effluent limitations. The Discharger is not required to duplicate the submittal of data that is entered in a tabular format within CIWQS. When electronic submittal of data is required and CIWQS does not provide for entry into a tabular format within the system, the Discharger shall electronically submit the data in a tabular format as an attachment. 10.2.7.2. The Discharger shall attach a cover letter to the SMR. The information contained in the cover letter shall clearly identify violations of the waste discharge requirements; discuss corrective actions taken or planned; and the proposed time schedule for corrective actions. Identified violations must include a description of the requirement that was violated and a description of the violation. 10.2.7.3. The Discharger shall electronically self-report all violations of the waste- discharge requirements using the CIWQS self-reported violations function. 10.3. Discharge Monitoring Reports (DMRs) 10.3.1. DMRs are U.S. EPA reporting requirements. The Discharger shall electronically certify and submit DMRs together with SMRs using Electronic Self-Monitoring Reports module eSMR 2.5 or any upgraded version. Electronic DMR submittal shall be in addition to electronic SMR submittal. Information about electronic DMR submittal is available at the DMR website at: (http://www.waterboards.ca.gov/water_issues/programs/discharge_monitoring). 10.4. Other Reports 10.4.1. The Discharger shall report the results of any special studies, acute and chronic toxicity testing, TRE/TIE, and PMP, required by Special Provisions – 6.3. The Discharger shall report the progress in satisfaction of compliance schedule dates specified in Special Provisions – 6.3.7. The Discharger shall submit reports with the first monthly SMR scheduled to be submitted on or immediately following the report due date. 10.4.2. The Discharger shall report the volumetric monitoring requirements as specified in Other Monitoring Requirements - 9.4 to the State Water Board by April 30 of each calendar year. The Discharger shall electronically certify and submit this annual report containing the required data via the State Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. Information about the volumetric reporting of wastewater and recycled water and the Recycled Water Policy is available at the Recycled Water Policy Volumetric Annual Reporting website at http://www.waterboards.ca.gov/recycledwaterpolicy. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-35 10.4.3. Every five years, the Discharger shall submit a Climate Change Implementation Progress Report as specified in section 6.3.6.2 of this Order. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-1 F. ATTACHMENT F – FACT SHEET TABLE OF CONTENTS 1. PERMIT INFORMATION .......................................................................................... F-3 2. FACILITY DESCRIPTION ........................................................................................ F-5 2.1. Description of Wastewater and Biosolids Treatment and Controls ........................ F-5 2.2. Discharge Points and Receiving Waters ............................................................... F-6 2.3. Summary of Existing Requirements and Self Monitoring Report Data .................. F-6 2.4. Summary of Interim Effluent Limits and Time Schedule Orders ............................ F-8 2.5. Compliance Summary ........................................................................................... F-9 2.6. Planned Changes ................................................................................................ F-10 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS ...................................... F-10 3.1. Legal Authorities.................................................................................................. F-11 3.2. California Environmental Quality Act (CEQA) ..................................................... F-11 3.3. State and Federal Laws, Regulations, Policies, and Plans ................................. F-11 3.4. Impaired Waterbodies on the CWA section 303(d) List ....................................... F-15 3.5. Other Plans, Polices and Regulations ................................................................. F-15 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS ................................................................................................................................... F-17 4.1. Discharge Prohibitions ........................................................................................ F-17 4.2. Technology-Based Effluent Limitations ............................................................... F-18 4.3. Water Quality-Based Effluent Limitations (WQBELs) .......................................... F-20 4.4. Final Effluent Limitation Considerations .............................................................. F-42 4.5. Interim Effluent Limitations – Not Applicable ....................................................... F-47 4.6. Land Discharge Specifications – Not Applicable ................................................. F-47 4.7. Recycling Specifications ...................................................................................... F-47 4.8. Point of Compliance for Effluent Limitations ........................................................ F-47 5. RATIONALE FOR RECEIVING WATER LIMITATIONS ........................................ F-48 5.1. Surface Water ..................................................................................................... F-48 6. RATIONALE FOR PROVISIONS ........................................................................... F-48 6.1. Standard Provisions ............................................................................................ F-48 6.2. Special Provisions ............................................................................................... F-48 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS .............. F-52 7.1. Influent Monitoring ............................................................................................... F-53 7.2. Effluent Monitoring .............................................................................................. F-53 7.3. Whole Effluent Toxicity Testing Requirements .................................................... F-53 7.4. Recycled Water Monitoring ................................................................................. F-54 7.5. Receiving Water Monitoring ................................................................................ F-54 7.6. Other Monitoring Requirements .......................................................................... F-55 9. PUBLIC PARTICIPATION ...................................................................................... F-58 9.1. Notification of Interested Persons........................................................................ F-58 9.2. Written Comments ............................................................................................... F-58 9.4. Reconsideration of Waste Discharge Requirements ........................................... F-59 9.5. Information and Copying ..................................................................................... F-59 9.6. Register of Interested Persons ............................................................................ F-60 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-2 9.7. Additional Information .......................................................................................... F-60 TABLE OF TABLES Table F-1. Facility Information ...................................................................................... F-3 Table F-2. Historic Effluent Limitations and Monitoring Data ........................................ F-7 Table F-3. TSO R3-2014-0036 Interim Effluent Limits ................................................. F-9 Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 ...... F-9 Table F-5. Basin Plan Beneficial Uses ....................................................................... F-12 Table F-6. Secondary Treatment Requirements ........................................................ F-19 Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 ................. F-19 Table F-8. Summary of RPA Results ......................................................................... F-23 Table F-9. Summary of Acute and Chronic Toxicity Test Results .............................. F-39 Table F-10. Final Effluent Limitations – Discharge Point EFF-001 ............................. F-44 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-3 ATTACHMENT F – FACT SHEET As described in section 2.2 of this Order, the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) incorporates this Fact Sheet as findings of the Central Coast Water Board supporting the issuance of this Order. This Fact Sheet includes the legal requirements and technical rationale that serve as the basis for the requirements of this Order. This Order has been prepared under a standardized format to accommodate a broad range of discharge requirements for dischargers in California. Only those sections or subsections of this Order that are specifically identified as “not applicable” have been determined not to apply to this Discharger. Sections or subsections of this Order not specifically identified as “not applicable” are applicable to this Discharger. 1. PERMIT INFORMATION The following table summarizes administrative information related to the facility. Table F-1. Facility Information WDID 3 400107001 Discharger City of San Luis Obispo Name of Facility City of San Luis Obispo Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Facility Contact, Title and Phone Patrick McGrath, WRRF Supervisor 805-781-7240 Authorized Person to Sign and Submit Reports Patrick McGrath, WRRF Supervisor 805-781-7240 Mailing Address 35 Prado Road, San Luis Obispo, CA 93401 Billing Address 35 Prado Road, San Luis Obispo, CA 93401 Type of Facility Publicly Owned Treatment Works (POTW) Major or Minor Facility Major Threat to Water Quality 2 Complexity A Pretreatment Program Yes CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-4 Recycling Requirements Production: NPDES R3-2024-0001 Distribution and Use: WQ 2016-0068, DDW Water Reclamation Requirements for Recycled Water Facility Permitted Flow 5.4 million gallons per day (MGD) Facility Design Flow 5.4 MGD Watershed Estero Bay Hydrologic Unit Receiving Water San Luis Obispo Creek Receiving Water Type Inland surface water 1.1. The City of San Luis Obispo (hereinafter Discharger or the City) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (hereinafter Facility), a publicly owned treatment works (POTW). For the purposes of this Order, references to the “discharger” or “permittee” in applicable federal and state laws, regulations, plans, or policy are held to be equivalent to references to the Discharger herein. 1.2. The Facility discharges wastewater to San Luis Obispo Creek, a water of the United States. 1.3. When applicable, state law requires dischargers to file a petition with the State Water Resources Control Board (State Water Board), Division of Water Rights and receive approval for any change in the point of discharge, place of use, or purpose of use of treated wastewater that decreases the flow in any portion of a watercourse. The State Water Board retains separate jurisdictional authority to enforce any applicable requirements under California Water Code section 1211. This is not an NPDES permit requirement. 1.4. The Discharger was previously regulated by Order R3-2014-0033 and National Pollutant Discharge Elimination System (NPDES) Permit CA0049224 adopted on September 25, 2014, and effective on December 1, 2014. The Discharger was also regulated by Time Schedule Order R3-2014-0036 and Time Schedule Order R3- 2019-0124. The Discharger filed a Report of Waste Discharge (ROWD) and submitted an application for reissuance of its waste discharge requirements (WDRs) and NPDES permit on May 28, 2019. 1.5. The Discharger was previously regulated by Waste Discharge Requirements and Master Reclamation Requirements Order R3-2003-081, which authorized the production, distribution, and use of recycled water. 1.6. Federal regulations at 40 C.F.R. section 122.46 limit the duration of NPDES permits to a fixed term not to exceed five years. However, pursuant to California Code of Regulations, title 23, section 2235.4, the terms and conditions of an expired permit are automatically continued pending reissuance of the permit if the Discharger complies with all federal NPDES requirements for continuation of expired permits. Because the Discharger met the requirements of California Code of Regulations, title 23, section 2235.4, Order No. R3-2014-0033, NPDES Permit No. CA0049224 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-5 was administratively continued after the original expiration date of November 30, 2019. 2. FACILITY DESCRIPTION 2.1. Description of Wastewater and Biosolids Treatment and Controls The City of San Luis Obispo Resource Recovery Facility is a municipal wastewater collection, treatment, and disposal facility that discharges tertiary treated wastewater to San Luis Obispo Creek. First constructed in 1920 and located at the southwest corner of the City of San Luis Obispo and adjacent to San Luis Obispo Creek, the Facility provides sewerage service to approximately 47,328 municipal and industrial users from the City of San Luis Obispo, California Polytechnic State University, San Luis Obispo, and the San Luis Obispo County Regional Airport. The City also administers an approved pretreatment program that includes seven significant industrial users, as defined in federal regulations. The Discharger currently operates a collection system that is composed of over 148 miles of main line and 9 lift stations. The design flow capacity of the Facility is 5.4 MGD. During storm events, the estimated wet weather influent flow to the facility is 11.1 MGD due to inflow and infiltration into the collection system from aging or broken/cracked pipes. Ongoing capital improvement projects for sewer line replacement, flow metering, and main line repairs will continue to address areas of concern that result in inflow and infiltration into the Facility. The Discharger has been implementing a significant upgrade of the Facility’s biological, disinfection, and biosolids units since 2019. A focus of the facility upgrade was to improve removal of chorine disinfection byproducts (trihalomethanes, or THMs) and nitrate to meet effluent limits of the previous permit. Another focus of the upgrade was to increase the facility’s ability to treat high inflows from wet-weather events. Prior to the most recent upgrades, the facility’s treatment process consisted of an equalization basin, mechanical screening, grit removal, primary settling, biofiltration, secondary settling, nitrification with two activated sludge aeration basins, final settling, cooling using evaporative cooling towers, dual media filtration, and chlorination/dechlorination. During the upgrade, the discharger removed or abandoned the following components of the facility: bio filter and secondary clarifier, final clarifiers, tertiary dual media filtration, and chlorine disinfection and dechlorination. The two activated sludge basins were converted to Modified Ludzack-Ettinger (MLE) bioreactors for nutrient removal, the dissolved air floatation thickener (DAFT) was modified into a sludge blend tank, and a digester was modified into an odor control unit. The final upgraded treatment system currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four MLE bioreactors, hollowfiber membranes, and UV disinfection. Although chlorination and dechlorination of the effluent and recycled water has been terminated due to the use of UV disinfection, the recycled water sent to the storage tank will be dosed with chlorine to maintain a chlorine residual in the recycled water distribution line per best practices of the distribution system. The Discharger may use sodium hypochlorite (chlorine) for CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-6 maintenance purposes such as membrane cleaning in the MLE unit when hydrogen peroxide and/or citric acid is insufficient. If chlorine is used for membrane cleaning, dechlorination of the effluent with sodium bisulfite may be necessary remove the chlorine residual to protect beneficial uses of San Luis Obispo Creek. Biosolids were previously handled with a dissolved air floatation thickener (DAFT), three anaerobic digesters, a screw press, a belt filter press, and drying beds, with the final product shipped out for composting. The upgraded biosolids handling unit now consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. There are two lined evaporation ponds located at southwest corner of the Facility property. The Discharger has occasionally diverted wastewater to these ponds when it did not meet effluent limitations, rather than discharging the wastewater to the creek. This Order requires the Discharger to submit a written notification to the Central Coast Water Board when wastewater is sent to these ponds. This Order does not provide regulatory coverage for the discharge of wastewater from these ponds to land or surface water. In recent years with large, prolonged storm events, these ponds have filled with stormwater from overland flow (not from the facility). This Order does not provide coverage of stormwater discharge from these ponds. As discussed further in section 3.5.1 of this Fact Sheet, the Discharger is enrolled in the Industrial General Permit (State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001). The Discharger may incorporate these ponds into their Industrial General Permit enrollment to allow for the discharge of stormwater from the ponds, in compliance with all the requirements of the Industrial General Permit. 2.2. Discharge Points and Receiving Waters Tertiary treated wastewater is discharged from Discharge Point EFF-001 to San Luis Obispo Creek, a water of the United States, at latitude 35.244307° N and longitude -120.680618° W. Sampling location EFF-001 A is located prior to discharge into the effluent pipeline that discharges to San Luis Obispo Creek. Sampling location EFF-001 B is located at the most downstream end of the effluent pipeline that discharges to San Luis Obispo creek. The flowrate in San Luis Obispo Creek varies greatly between the wet and dry seasons. No dilution credit has been granted for this discharge. Tertiary treated wastewater is discharged from Discharge Point EFF-002 to the Discharger’s reclaimed water storage tank that is located just south of the UV disinfection system. The reclaimed water storage tank feeds the Discharger’s reclaimed water distribution lines located throughout the city. 2.3. Summary of Existing Requirements and Self Monitoring Report Data Effluent limitations contained in Order R3-2014-0033 for discharges from Discharge Point 001 (Monitoring Location EFF-001) and representative monitoring data from December 1, 2014, to December 1, 2022, are shown in Table F-2: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-7 Table F-2. Historic Effluent Limitations and Monitoring Data Parameter Units Averag e Monthl y Effluen t Limit Averag e Weekly Effluen t Limit Maximum Daily Effluent Limit Highest Average Monthly Discharge Reported Highest Average Weekly Discharge Reported Highest Daily Discharge Reported Flow (dry weather) MGD 5.1 --- --- 8.0 --- 12.9[1] Biochemical Oxygen Demand 5- day @ 20°C (BOD5) milligra ms per liter (mg/L) 10 30 50 8.84 14.3 12.6 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) pounds per day (lbs/day ) 425 1275 2125 382 382 382 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) percent removal ≥85 --- --- 91.6 – 100[2] Total Suspended Solids (TSS) mg/L 10 30 75 7.9 11 23.3 Total Suspended Solids (TSS) lbs/day 425 1275 3190 572 842 1556 Total Suspended Solids (TSS) percent removal ≥85 --- --- 97.3-99.7[2] --- --- Oil and Grease mg/L 5 --- 10 8 --- 8 Settleable Solids milliliter per liter per hour (mL/L/h r) 0.1 --- --- <0.1 --- --- pH standar d units 6.5– 8.3[3] 6.5 – 7.88[4] Nitrate, Total (as N) mg/L 10 --- --- 51.7 --- --- Chlorodibro momethane µg/L 0.4 --- 1.0 5 --- 5 Dichlorobro momethane µg/L 0.56 --- 1.0 22 --- 22 N- Nitrosodimet hylamine µg/L 0.0006 9 --- 0.0014 ND --- ND Dissolved Oxygen mg/L 4.0[5] 4.8 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-8 Chlorine Residual mg/L --- --- ND[6] --- --- 0.76 Chronic Toxicity Toxic Units Chronic (TUc) --- --- 1.0 --- --- 4.0 Fecal or Total Coliform Bacteria Most probabl e number (MPN)/ 100 mL [7] [8] [9] 79, 94[10] 1.8 350 [1] Reported as maximum daily. Flow occurred in February 2017 during a wet weather event. [2] The numbers represent the range of lowest to highest reported values. [3] Applied as an instantaneous minimum and maximum effluent limitation. [4] Representative values contain the lowest instantaneous minimum to the highest instantaneous maximum. [5] Applied as an instantaneous minimum effluent limitation. [6] ND = less than 0.1 mg/L. Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [7] No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30-day period. [8] The median number of fecal coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days for which analyses have been completed. [9] The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [10] Values occurred within a 30-day time period. 2.4. Summary of Interim Effluent Limits and Time Schedule Orders During the permit term for Order R3-2014-0036, the discharger could not immediately achieve compliance with the chlorodibromomethane, dichlorobromomethane, and nitrate effluent limitations. The Central Coast Water Board issued two time schedule orders (TSOs) to set interim effluent limits and compliance timelines: TSO R3-2014- 0036 and TSO R3-2019-0124. TSO R3-2014-0036 set interim limits for the three aforementioned effluent limits with full compliance with effluent limits by November 30, 2019. With the planned upgrades to the Facility’s biological and disinfection units, TSO R3-2019-0124 extended the deadlines to meet the interim effluent limits with a compliance deadline of March 31, 2020, for chlorodibromomethane and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-9 dichlorobromomethane and a compliance deadline of July 31, 2023 for nitrate. Table F- 3 summarizes the interim effluent limits that were established. The interim effluent limitations were established based on the Facility’s performance. When operating under a TSO, if effluent concentrations exceed the final effluent limitation but do not exceed the interim effluent limitation, an effluent violation has not occurred, and mandatory minimum penalties do not apply. If effluent concentrations exceed both the final and interim effluent limitation values, then an effluent violation has occurred, and mandatory minimum penalties do apply. Table F-3. TSO R3-2014-0036 Interim Effluent Limits Constituent Units Average Monthly Maximum Daily Chlorodibromomethane µg/L - 42 Dichlorobromomethane µg/L - 36 Nitrate (as Nitrogen) mg/L 42.6 - 2.5. Compliance Summary 2.5.1 Effluent Compliance Summary The following discussion is a summary of the violations that occurred during the term and administrative extension of Order No. R3-2014-0033. During the time period from December 1, 2014, to May 31, 2023, the Discharger incurred effluent violations related to nitrate, oil and grease, total coliform, chlorine residual, dichlorobromomethane, and chlorodibromomethane. The number of violations, violation type, and reported value range are provided in Table F-4. Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Nitrate (Total as N) December 2016- November 2022 Monthly Average (Mean) Limit 9 43.2-51.7 10 mg/L Oil and Grease March 2017 Monthly Average Limit 1 6 5 mg/L CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-10 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Total Coliform July 2018- October 2020 30-Day Specific Limit 3 33-1600 23 MPN/ 100m L Total Coliform December 2019- October 2020 Daily Maximum 3 540-1600 240 MPN/ 100m L Residual Chlorine February 2020- December 2022 Daily Maximum 2 0.35-0.75 ND mg/L Dichlorobro momethane April 2020- October 2022 Monthly Average Limit 4 2.5-17.8 0.56 µg/L Dichlorobro momethane April 2020- October 2022 Daily Maximum 4 2.5-17.8 1 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Monthly Average Limit 3 1.2-5 0.40 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Daily Maximum 3 1.2-5 1 µg/L 2.6. Planned Changes The Discharger will continue to implement planned upgrades through 2024. The Discharger has not indicated it plans any significant changes to the Facility beyond those during the term of the Order. 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS The requirements contained in this Order are based on the requirements and authorities described in this section. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-11 3.1. Legal Authorities This Order serves as WDRs pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA), implementing regulations promulgated by the U.S. Environmental Protection Agency (U.S. EPA), and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as an NPDES permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1, subject to the WDRs in this Order. 3.2. California Environmental Quality Act (CEQA) Under California Water Code section 13389, this action to adopt an NPDES permit for an existing facility is exempt from the California Environmental Quality Act (CEQA) provisions in Public Resources Code, division 13, chapter 3 (commencing with section 21100). With respect to the recycling specifications and groundwater limitations, this action is exempt from the provisions of CEQA pursuant to title 14, California Code of Regulations, section 15301, class 1 exemption for permitting of existing facilities with no expansion of existing use. 3.3. State and Federal Laws, Regulations, Policies, and Plans 3.3.1. Water Quality Control Plan. The Central Coast Water Board adopted the Water Quality Control Plan for the Central Coastal Basin (Basin Plan), which designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for all waters addressed through the plan. Requirements in this Order implement the Basin Plan. In addition, the Basin Plan implements State Water Board Resolution 88-63, which established state policy that all waters, with certain exceptions, should be considered suitable or potentially suitable for municipal or domestic supply. Beneficial uses established by the 2019 Basin Plan for San Luis Obispo Creek (below W. Marsh Street) are presented below: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-12 Table F-5. Basin Plan Beneficial Uses Discharge Point Receiving Water Name Beneficial Use(s) 001 San Luis Obispo Creek (below W. Marsh Street) Existing: Municipal and Domestic Supply (MUN); Agricultural Supply (AGR); Ground Water Recharge (GWR); Water Contact Recreation (REC-1); Non-Contact Water Recreation (REC-2); Wildlife Habitat (WILD); Cold Freshwater Habitat (COLD); Warm Freshwater Habitat (WARM); Migration of Aquatic Organisms (MIGR) Spawning, Reproduction, and/or Early Development (SPWN); Fresh Water Replenishment (FRSH) Commercial and Sport Fishing (COMM). Intermittent: None. Potential: None. Groundwater throughout the Central Coast Region has designated beneficial uses of agricultural water supply, municipal and domestic water supply, and industrial use. Requirements of this Order implement the Basin Plan. 3.3.2. Thermal Plan. The State Water Board adopted the Water Quality Control Plan for Control of Temperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of California (Thermal Plan) January 7, 1971, and amended the plan on September 18, 1975. This plan contains temperature objectives for surface waters. Requirements of this Order implement the Thermal Plan. 3.3.3. Sediment Quality. The State Water Board adopted the Water Quality Control Plan for Enclosed Bays and Estuaries – Part 1, Sediment Quality on September 16, 2008, and it became effective on August 25, 2009. This plan supersedes other narrative sediment quality objectives and establishes new sediment quality objectives and related implementation provisions for specifically defined sediments in most bays and estuaries. Requirements of this Order implement sediment quality objectives of this plan. 3.3.4. National Toxics Rule (NTR) and California Toxics Rule (CTR). U.S. EPA adopted the NTR on December 22, 1992, and later amended it on May 4, 1995, and November 9, 1999. About forty criteria in the NTR apply in California. On May 18, 2000, U.S. EPA adopted the CTR. The CTR promulgated new toxics criteria for California and, in addition, incorporated the previously adopted NTR criteria CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-13 that were applicable in the state. The CTR was amended on February 13, 2001. These rules contain federal water quality criteria for priority pollutants. 3.3.5. State Implementation Policy. On March 2, 2000, the State Water Board adopted Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (State Implementation Policy or SIP). The SIP became effective on April 28, 2000, with respect to the priority pollutant criteria promulgated for California by the U.S. EPA through the NTR and to the priority pollutant objectives established by the Central Coast Water Board in the Basin Plan. The SIP became effective on May 18, 2000, with respect to the priority pollutant criteria promulgated by the U.S. EPA through the CTR. The State Water Board adopted amendments to the SIP on February 24, 2005, that became effective on July 13, 2005. 3.3.6 Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (ISWEBE Plan). The ISWEBE Plan includes several parts and sections that have been adopted by the State Water Board over time. The applicable parts and sections are discussed below. On May 2, 2017, the State Water Board adopted and ISWEBE Plan Part 2: Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. With ISWEBE Plan Part 2’s approval, the State Water Board approved one new narrative and four new numeric mercury water quality objectives to apply to those inland surface waters, enclosed bays, and estuaries of the state that have any of the following beneficial use designations: COMM, CUL, T-SUB, WILD, MAR, RARE, WARM, COLD, EST, or SAL. The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On August 7, 2018, the State Water Board adopted ISWEBE Plan Part 3: Bacteria Provisions and a Water Quality Standards Variance Policy, which establishes water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On December 1, 2020, the State Water Board adopted the Aquatic Toxicity Provisions, which are incorporated into the ISWEBE Plan. On October 5, 2021, the State Water Board adopted a resolution to confirm that the Aquatic Toxicity Provisions were adopted as state policy for water quality control for all inland surface waters, enclosed bays, estuaries, and coastal lagoons of the state. The provisions were approved by the California Office of Administrative Law on April 25, 2022 and were approved by the U.S. EPA on May 1, 2023. The provisions include statewide numeric water quality objectives for both acute and chronic toxicity and a program of implementation to control toxicity. The provisions provide consistent protection of aquatic life beneficial uses in inland surface waters, enclosed bays, estuaries, and coastal lagoons throughout the state from the effects of known and unknown toxicants. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-14 This Order is consistent with the ISWEBE Plan and includes effluent limitations for mercury, bacteria, and chronic toxicity. 3.3.6. Domestic Water Quality. In compliance with California Water Code section 106.3, it is the policy of the State of California that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. This Order promotes that policy by requiring discharges to meet water quality objectives established in the Basin Plan that are based on drinking water maximum contaminant levels and designed to protect human health and ensure that water is safe for domestic use. 3.3.7. Antidegradation Policy. Federal regulation 40 C.F.R. section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal policy. The State Water Board established California’s antidegradation policy in State Water Board Resolution 68-16, Statement of Policy with Respect to Maintaining High Quality of Waters in California. Resolution 68-16 is deemed to incorporate the federal antidegradation policy where the federal policy applies under federal law. Resolution 68-16 requires that existing water quality be maintained unless degradation is justified by specific findings. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The permitted discharge must be consistent with the antidegradation provision of 40 C.F.R. section 131.12 and State Water Board Resolution 68-16. 3.3.8. Anti-Backsliding Requirements. Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. section 122.44(l) restrict backsliding in NPDES permits. These anti-backsliding provisions require that effluent limitations in a reissued permit must be as stringent as those in the previous permit, with some exceptions in which limitations may be relaxed. 3.3.9. Endangered Species Act Requirements. This Order does not authorize any act that results in the taking of a threatened or endangered species or any act that is now prohibited, or becomes prohibited in the future, under either the California Endangered Species Act (Fish and Game Code sections 2050 to 2097) or the Federal Endangered Species Act (16 U.S.C. sections 1531 to 1544). This Order requires compliance with effluent limits, receiving water limits, and other requirements to protect the beneficial uses of waters of the state. The Discharger is responsible for meeting all applicable requirements of the endangered species acts. 3.3.10. Sewage Sludge and Biosolids. This Order does not authorize any act that results in violation of requirements administered by U.S. EPA to implement 40 C.F.R. part 503, Standards for the Use or Disposal of Sewage Sludge. These standards regulate the final use or disposal of sewage sludge that is generated during the treatment of domestic sewage in a municipal wastewater treatment facility. The Discharger is responsible for meeting all applicable requirements of 40 C.F.R. part 503 that are under U.S. EPA’s enforcement authority. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-15 3.4. Impaired Waterbodies on the CWA section 303(d) List CWA section 303(d) requires states to identify and make a list of specific water bodies where water quality standards are not expected to be met after implementation of technology-based effluent limitations on point sources. For all CWA section 303(d) listed water bodies and pollutants, the Central Coast Water Board must develop and implement total maximum daily loads (TMDLs) that specify waste load allocations (WLAs) for point sources and load allocations (LAs) for non- point sources. The U.S. EPA approved the State’s 2020-2022 303(d) list of impaired water bodies on May 11, 2022. The 2020-2022 303(d) list identifies San Luis Obispo Creek, below Osos Street, as impaired for chloride, sodium, benthic community effects, Escherichia coli (E. coli), dissolved oxygen, nitrate, and toxicity. A TMDL for nitrate was adopted for San Luis Obispo Creek below West Marsh Street. Effluent limitations for nitrate in this Permit are based on Central Coast Water Board Resolution R3-2005-0106 (TMDL for nitrate). A TMDL for pathogens was adopted for San Luis Obispo Creek (R3-2004-0142) but the Facility was not identified as a source and was not assigned a wasteload allocation. However, the Discharger is implementing a Wasteload Allocation Attainment Plan (WAAP) to address pathogens from the sources identified in the TMDL. 3.5. Other Plans, Polices and Regulations 3.5.1. State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001, Waste Discharge Requirements for Stormwater Associated with Industrial Activities Excluding Construction Activities (Industrial General Permit). The Industrial General Permit, adopted April 1, 2014, amended August 4, 2015, and November 6, 2018, and effective July 1, 2015, is applicable to POTWs with a design capacity greater than 1.0 MGD. The purpose of the Industrial General Order is to regulate stormwater discharges associated with industrial activities. For the control of stormwater discharged from the Facility, the Discharger has enrolled in and is regulated by the Industrial General Permit. 3.5.2. State Water Board Order. 2022-0103-DWQ Statewide General Waste Discharge Requirements for Sanitary Sewer Systems. State Water Board Order No. 2022-0103-DWQ, adopted on December 6, 2022, is applicable to all "federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California." The purpose of Water Quality Order 2022-0103-DWQ is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled in Water Quality Order 2022-0103-DWQ and must comply with its requirements and any requirements in reissuances to Water Quality Order 2022-0103-DWQ. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-16 3.5.3. State Water Board Recycled Water Policy. The State Water Board adopted the Quality Control Policy for Recycled Water (Recycled Water Policy) on December 11, 2018, and it became effective on April 8, 2019. The purpose of the Recycled Water Policy is to encourage the safe use of recycled water in a manner that is protective of public health and the environment. This Order implements the Recycled Water Policy by supporting the production of recycled water and requiring volumetric reporting of wastewater and recycled water to the State Water Board. The Recycled Water Policy calls for the development of regional groundwater basin/sub-basin salt/nutrient management plans. This Order requires the Discharger to continue to commit funding and in-kind resources to facilitate development of a regional groundwater basin/sub-basin salt/nutrient management plan that implements the Recycled Water Policy. 3.5.4 Statewide General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW). State Water Board Order WQ 2016-0068-DDW, adopted on June 7, 2016, is applicable to recycled water projects where recycled water is used or transported for non-potable uses. The distribution and offsite reuse of recycled water produced by the Facility is subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. 3.5.5 Environmental Justice and Advancing Racial Equity. When issuing or reissuing individual waste discharge requirements or waivers of waste discharge requirements that regulate an activity or a facility that may impact a disadvantaged or tribal community, and that includes a time schedule in accordance with subdivision (c) of Section 13263 for achieving an applicable water quality objective, an alternative compliance path that allows time to come into compliance with water quality objectives, or a water quality variance, the Central Coast Water Board shall make a finding on potential environmental justice, tribal impact, and racial equity considerations. (Water Code § 13149.2, effective Jan. 1, 2023). Water Code section 189.7 requires the Central Coast Water Board to conduct outreach in disadvantaged and/or tribal communities when adopting individual waste discharge requirements. In accordance with the Water Boards’ efforts to advance racial equity, the Central Coast Water Board is also committed to developing and implementing policies and programs to advance racial equity and environmental justice so that race can no longer be used to predict life outcomes, and outcomes for all groups are improved. Upon review of readily available information, the Central Coast Water Board finds that this Order regulates a discharge that does not disproportionately impact the water quality of an economically disadvantaged community or a tribal community. Similarly, this Order does not include a time schedule, alternative compliance path, or variance. Therefore, Water Code section 13149.2 does not apply to this permit reissuance. Nevertheless, the Central Coast Water Board has conducted outreach consistent with Water Code section 189.7 by reaching out to surrounding communities and tribal communities about this Order. Additionally, the Board has considered any environmental justice concerns within the Board’s authority, in accordance with the Water Boards’ efforts to advance racial equity. The Order CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-17 requires the Permittee to meet water quality standards to protect public health and the environment, thereby benefiting all persons and communities within the Region. 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS The CWA requires point source dischargers to control the amount of conventional, non-conventional, and toxic pollutants that are discharged into the waters of the United States. The control of pollutants discharged is established through effluent limitations and other requirements in NPDES permits. There are two principal bases for effluent limitations in the Code of Federal Regulations: 40 C.F.R. section 122.44(a) requires that permits include applicable technology-based limitations and standards, and 40 C.F.R. section 122.44(d) requires that permits include water quality-based effluent limitations to attain and maintain applicable numeric and narrative water quality criteria to protect the beneficial uses of receiving waters. When numeric water quality objectives have not been established, but a discharge has the reasonable potential to cause or contribute to exceedances of water quality standards described at 40 C.F.R. section 122.44 (d), then 1) water quality based effluent limitations (WQBELS) may be established using a calculated water quality criterion derived from a proposed state criterion or an explicit State policy or regulation interpreting its narrative criterion, 2) WQBELs may be established on a case-by-case basis using U.S. EPA criteria guidance published under CWA Section 304 (a), or 3) WQBELs may be established using an indicator parameter for the pollutant of concern. Several specific factors affecting the development of limitations and requirements in this Order are discussed below. 4.1. Discharge Prohibitions 4.1.1. Discharge Prohibition 3.1. (No discharge at a location or in a manner except as described by the Order). The Order authorizes a single, specific point of discharge to surface waters, and the limitations and conditions established by the Order are based on specific information provided by the Discharger and gained by the Central Coast Water Board through site visits, review of monitoring reports, and other information. Discharges to surface waters at locations not contemplated by this Order or discharges of a character not contemplated by this Order are therefore viewed as inconsistent with CWA section 402’s prohibition against discharges of pollutants except in compliance with the CWA’s permit requirements, effluent limitations, and other enumerated provisions. This prohibition is retained from the previous permit. 4.1.2. Discharge Prohibition 3.2. (Discharge of any waste not specifically regulated by this Order is prohibited). Because limitations and conditions of the Order are based on specific information provided by the Discharger and specific wastes described by the Discharger, the limitations and conditions of the Order do not adequately address waste streams not contemplated during drafting of the Order. To prevent the discharge of such waste streams that may be inadequately CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-18 regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.1.3. Discharge Prohibition 3.3. (Overflow, bypass, or overspray of wastewater from the Discharger’s facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7. (Bypass), is prohibited). The discharge of untreated or partially treated wastewater from the Discharger’s collection, treatment, or disposal facilities represents an unauthorized bypass pursuant to 40 C.F.R. section 122.41(m) or an unauthorized discharge that poses a threat to human health and/or aquatic life, and, therefore, is explicitly prohibited by this Order. 4.1.4. Discharge Prohibition 3.4. (Creation of a condition of pollution, contamination, or nuisance, as defined by Section 13050 of the California Water Code, is prohibited). The Basin Plan requires that the disposal of wastewater to waterbodies be accomplished in a manner that safeguards public health and prevents nuisance conditions. 4.1.5. Discharge Prohibition 3.5. (Discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat). This prohibition is consistent with the requirements of the Basin Plan. 4.1.6. Discharge Prohibition 3.6. (Discharge of radioactive substances is prohibited). This prohibition is consistent with the requirements of the Basin Plan. 4.1.7. Discharge Prohibition 3.7. (Monthly average dry weather effluent flow shall not exceed 5.4 million gallons per day (MGD), aggregated at Discharge Point 001). To prevent the discharge of such waste streams that may be inadequately regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.2. Technology-Based Effluent Limitations 4.2.1. Scope and Authority Section 301(b) of the CWA and implementing U.S. EPA permit regulations at 40 C.F.R. § 122.44 require that permits include conditions meeting applicable technology-based requirements at a minimum, and any more stringent effluent limitations necessary to meet applicable water quality standards. Where the USEPA has not yet developed technology-based standards for a particular industry or a particular pollutant, CWA Section 402 (a) (1) and USEPA regulations at 40 C.F.R. § 125.3 authorize the use of best professional judgment (BPJ) to derive technology-based effluent limitations on a case-by-case basis. When BPJ is used, the permit writer must consider specific factors outlined at 40 C.F.R. § 125.3. Regulations promulgated in 40 C.F.R. § 125.3(a)(1) require technology- based effluent limitations for municipal dischargers to be placed in NPDES permits based on Secondary Treatment Standards or Equivalent to Secondary Treatment Standards. The Federal Water Pollution Control Act Amendments of 1972 (PL 92-500) established the minimum performance requirements for POTWs [defined in section 304(d)(1)]. Section 301(b)(1)(B) of that act requires CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-19 that such treatment works must, as a minimum, meet effluent limitations based on secondary treatment as defined by the U.S. EPA Administrator. Based on this statutory requirement, U.S. EPA developed secondary treatment regulations, which are specified in 40 C.F.R. part 133. These technology-based regulations apply to all municipal wastewater treatment plants and identify the minimum level of effluent quality attainable by secondary treatment in terms of biochemical oxygen demand (BOD5), total suspended solids (TSS), and pH. The discharge authorized by this Order must meet minimum federal technology-based requirements based on Secondary Treatment Standards at 40 C.F.R. part 133, summarized below: Table F-6. Secondary Treatment Requirements Parameter Units 30-Day Average 7-Day Average BOD5 [1] mg/L 30 45 TSS[1] mg/L 30 45 pH standard units 6.0[2] 9.0[3] [1] The 30-day average percent removal shall not be less than 85 percent. [2] Instantaneous minimum value. [3] Instantaneous maximum value. 4.2.2. Applicable Technology-Based Effluent Limitations 40 C.F.R. section122.45(f)(1) requires effluent limitations be expressed in terms of mass, with some exceptions, and 40 C.F.R. section 122.45(f)(2) allows pollutants that are limited in terms of mass to additionally be limited in terms of other units of measurement. This Order includes effluent limitations expressed in terms of mass and concentration. In addition, pursuant to the exceptions to mass limitations provided in 40 C.F.R. section 122.45(f)(1), some effluent limitations are not expressed in terms of mass, such as pH and temperature, as well as when the applicable standards are expressed in terms of concentration and mass limitations are not necessary to protect the beneficial uses of the receiving waters. 4.2.2.1. The following table summarizes technology-based effluent limitations established by this Order at Discharge Point 001. Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 Parameter Units 30-Day Average 7-Day Average Maximum Daily BOD5[1] mg/L 10 30 50 BOD5 lbs/day [2] 450 1,351 2,252 Total Suspended Solids (TSS)[1] mg/L 10 30 75 TSS lbs/day[2] 450 1,351 3,378 [1] The average monthly percent removal of BOD5 and TSS, as measured at Monitoring Location EFF-001, shall not be less than 85 percent. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-20 [2] Mass loading limits were calculated using the following formulas: lbs/day = pollutant concentration (mg/L) * permitted flow (5.4 MGD) * conversion factor (8.34) [3] Instantaneous minimum value. [4] Instantaneous maximum value. 4.2.2.1.1. BOD5 and TSS. BOD and TSS. Federal regulations, 40 C.F.R. part 133, establish the minimum weekly and monthly average level of effluent quality attainable by secondary treatment for BOD5 and TSS. The Central Coast Water Board has determined that tertiary treatment is necessary to protect the beneficial uses of the receiving stream, thus the final effluent limitations for BOD5 and TSS are based on the technical capability of the tertiary process. The secondary and tertiary treatment standards for BOD5 and TSS are indicators of the effectiveness of the treatment processes. The principal design parameter for wastewater treatment plants is the daily BOD5 and TSS loading rates and the corresponding removal rate of the system. In applying 40 C.F.R. part 133 for weekly and monthly average BOD5 and TSS limitations, the application of tertiary treatment processes results in the ability to achieve lower levels for BOD5 and TSS than the secondary standards currently prescribed; the 30-day average BOD5 and TSS limitations are 10 mg/L, the 7-day average BOD5 and TSS limitations are 30 mg/L. These effluent limitations are based on the capability of a tertiary system. In addition to the average weekly and average monthly effluent limitations, daily maximum effluent limitation of 50 mg/L and 75 mg/L for BOD5 and TSS, respectively, are included in the Order to ensure that the treatment works are not organically overloaded and operate in accordance with design capabilities. In addition, 40 C.F.R. § 133.102, in describing the minimum level of effluent quality attainable by secondary treatment, states that the 30-day average percent removal shall not be less than 85 percent. If 85 percent removal of BOD5 and TSS must be achieved by a secondary treatment plant, it must also be achieved by a tertiary (i.e., treatment beyond secondary level) treatment plant. This Order contains a limitation requiring an average of 85 percent removal of BOD5 and TSS over each calendar month. These effluent limitations are carried over from Order R3-2014-0033. 4.3. Water Quality-Based Effluent Limitations (WQBELs) 4.3.1. Scope and Authority CWA section 301(b) and 40 C.F.R. section 122.44(d) require that permits include limitations more stringent than applicable federal technology-based requirements where necessary to achieve applicable water quality standards. Section 122.44(d)(1)(i) of 40 C.F.R. requires that permits include effluent limitations for all pollutants that are or may be discharged at levels that have the reasonable potential to cause or contribute to an exceedance of a water quality standard, including numeric and narrative objectives within a standard. Where reasonable potential has been established for a pollutant, but there is no numeric criterion or objective for the pollutant, WQBELs must be established using: (1) U.S. EPA criteria guidance under CWA section 304(a), supplemented where CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-21 necessary by other relevant information; (2) an indicator parameter for the pollutant of concern; or (3) a calculated numeric water quality criterion, such as a proposed state criterion or policy interpreting the state’s narrative criterion, supplemented with other relevant information, as provided in section 122.44(d)(1)(vi). The process for determining reasonable potential and calculating WQBELs when necessary is intended to protect the designated uses of the receiving water as specified in the Basin Plan and to achieve applicable water quality objectives and criteria that are contained in other state plans and policies, or any applicable water quality criteria contained in the CTR and NTR. 4.3.2. Applicable Beneficial Uses and Water Quality Criteria and Objectives Beneficial uses described by the 2019 Basin Plan for San Luis Obispo Creek and they are presented in section 3.3.1 of this Fact Sheet. Water quality criteria applicable to this receiving water are established by the CTR, the NTR, and by the 2019 Basin Plan. 4.3.3. Determining the Need for WQBELs NPDES regulations at 40 CFR section 122.44(d) require effluent limitations to control all pollutants which are or may be discharged at a level which will cause, have the reasonable potential to cause, or contribute to an excursion above any State water quality standard. The SIP, the statewide policy that became effective on May 22, 2000, establishes procedures to implement water quality criteria from the NTR and CTR and for priority, toxic pollutant objectives established in the Basin Plan. The implementation procedures of the SIP include methods to determine reasonable potential (for pollutants to cause or contribute to excursions above State water quality standards) and to establish numeric effluent limitations, if necessary, for those pollutants which show reasonable potential. The SIP Section 1.3 requires the Central Coast Water Board to use all available valid, relevant, and representative receiving water and effluent data and information to conduct a reasonable potential analysis (RPA). The Central Coast Water Board analyzed the Discharger’s data for priority pollutants and the nature of the discharge to determine if the discharge has reasonable potential to exceed water quality standards. The RPA is based on effluent data retrieved from CIWQS from the period of December 2014 to December 2022. Some freshwater water quality criteria for metals are hardness dependent, i.e., as hardness decreases, the toxicity of certain metals increases, and the applicable water quality criteria become correspondingly more stringent. The Discharger has not specifically collected hardness data for the receiving water. However, the Central Coast Water Board’s Central Coast Ambient Monitoring Program has nearby monitoring stations on San Luis Obispo Creek that has collected this information. The Water Board used 330 mg/L as CaCO3 as a conservative estimate of the receiving water hardness to determine hardness-based criteria. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-22 To conduct the RPA, the Central Coast Water Board identified the maximum observed effluent (MEC) and background (B) concentrations for each priority, toxic pollutant from receiving water and effluent data provided by the Discharger and compared this data to the most stringent applicable water quality criterion (C) for each pollutant from the NTR, CTR, and the 2019 Basin Plan. The Discharger did not collect background data (B) for receiving water. Section 1.3 of the SIP establishes three triggers for a finding of reasonable potential. 4.3.3.1. Trigger 1. If the MEC is greater than C, there is reasonable potential, and an effluent limitation is required. 4.3.3.2. Trigger 2. If B is greater than C, and the pollutant is detected in effluent (MEC > ND), there is reasonable potential, and an effluent limitation is required. 4.3.3.3. Trigger 3. After reviewing other available and relevant information, a permit writer may decide that a WQBEL is required. Such additional information may include, but is not limited to: the facility type, the discharge type, solids loading analyses, lack of dilution, history of compliance problems, potential toxic impact of the discharge, fish tissue residue data, water quality and beneficial uses of the receiving water, CWA 303(d) listing for the pollutant, and the presence of endangered or threatened species or their critical habitat. For mercury in particular, Part 2 of the SIP revised the above methodology as follows, pursuant to State Water Board Resolution 2017-0027, Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California-Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions (Mercury Provisions). 4.3.3.4. Most stringent water quality objective. The RPA is to use a water column concentration from SIP Part 2’s Table 1 based on the receiving water body type and beneficial use(s) to identify the most stringent mercury water quality objective. For San Luis Obispo Creek, the applicable water column concentration is 0.012 ug/L total mercury. This water column concentration is to be used as the “C” value in the RPA for mercury. This change in methodology changes the water quality objective from 0.05 ug/L in the previous orders to 0.012 ug/L in this Order. 4.3.3.5. Maximum Effluent Concentration. Instead of using the highest observed mercury effluent concentration, the MEC is to be determined as an arithmetic mean of all mercury samples during a calendar year. For this RPA, the highest calendar year arithmetic mean based on the revised methodology for mercury in effluent was 0.03 ug/L. The Discharger collects effluent mercury samples on a yearly basis. 4.3.3.6. Maximum ambient background concentration. Instead of using the highest observed mercury concentration in the upstream receiving water (referred to as “B”), the value of B is to be determined as an arithmetic mean of all mercury samples during a calendar year. This Discharger did not sample for and does not have ambient background concentration data for mercury. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-23 4.3.3.7. Determination. A mercury WQBEL is not required unless the MEC is greater than C. However, if B is greater than C and mercury is detected in the effluent, effluent monitoring is required. A mercury WQBEL is required for this discharge because the MEC (i.e., the highest calendar year average concentration with using one half the mercury detection limits when non-detect) was greater than C and there was no B data available. Therefore, according to Part 2 of the SIP, a mercury effluent limitation is required. Annual monitoring for mercury will be retained from the previous Order. The following table summarizes the RPA for each priority, title 22, or Basin Plan pollutant for which data was available from December 2014 through December 2022 and sets forth the basis upon which WQBELs are included in this Order. Table F-8. Summary of RPA Results CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Priority Pollutants 1 Antimony, Total Recoverable µg/L 9 2.5 6 - No Primary MCL 2 Arsenic, Total Recoverable µg/L 9 <2.0 10 - No Primary MCL 3 Beryllium µg/L 9 <0.2 4 - No Primary MCL 4 Cadmium, Total Recoverable µg/L 9 <0.2 3 - No CA Prim. MCL 5a Chromium (III) µg/L 7 7.0 50 - No CA Prim. MCL for Chromium (Total) 5b Chromium (VI) µg/L 8 1.1 11 - No CTR - Chronic 6 Copper, Total Recoverable µg/L 9 24 26 - No CTR - Chronic 7 Lead, Total Recoverable µg/L 8 6.3 15 - No CA Prim. MCL 8 Mercury, Total Recoverable µg/L 9 0.03 0.012 - Yes Mercury Provisions 9 Nickel, Total Recoverable µg/L 9 7.0 100 - No CA Prim. MCL 10 Selenium, Total Recoverable µg/L 9 1.0 5 - No CTR - Chronic CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-24 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 11 Silver, Total Recoverable µg/L 8 <0.25 31.6 - No CTR - Acute 12 Thallium, Total Recoverable µg/L 9 <0.2 1.7 - No CTR 13 Zinc, Total Recoverable µg/L 9 100 330 - No CTR 14 Cyanide, Total (as CN) µg/L 9 <4.0 5.2 - No CTR 15 Asbestos Million Fibers/L 9 <0.2 7 - No CTR 16 2,3,7,8 TCDD µg/L 9 <0.00000 0251 0.00000001 3 - Ud CTR 17 Acrolein µg/L 8 <5.0 320 - No CTR 18 Acrylonitrile µg/L 8 <2.0 0.059 - Ud CTR 19 Benzene µg/L 9 <0.5 1 - No CA Prim. MCL 20 Bromoform µg/L 73 1.1 4.3 - No CTR 21 Carbon Tetrachloride µg/L 9 <0.5 0.25 - Ud CTR 22 Chlorobenzene µg/L 9 <0.5 70 - No CA Prim. MCL 23 Chlorodibromomethane (aka Dibromochloromethane) µg/L 73 5.4 0.401 - Yes CTR 24 Chloroethane µg/L 8 <0.5 No Criteria - Uc No criteria 25 2-Chloroethylvinyl ether µg/L 8 <1.0 No Criteria - Uc No criteria 26 Chloroform µg/L 8 95.7 60 - Yes NAWQC 27 Dichlorobromomethane µg/L 73 24.8 0.56 - Yes CTR 28 1,1-Dichloroethane µg/L 9 <0.5 5 - No Primary MCL 29 1,2-Dichloroethane µg/L 9 <0.5 0.38 - Ud CTR 30 1,1-Dichloroethylene µg/L 9 <0.5 0.057 - No CTR 31 1,2-Dichloropropane µg/L 9 <0.5 0.52 - No CTR 32 1,3-Dichloropropylene µg/L 1 <0.5 0.5 - No CA Prim. MCL 33 Ethylbenzene µg/L 9 <0.5 300 - No CA Prim. MCL 34 Methyl Bromide (aka Bromomethane) µg/L 8 <0.5 48 - No CTR 35 Methyl Chloride (aka chloromethane) µg/L 8 <0.5 No Criteria - Uc No criteria 36 Methylene Chloride µg/L 9 15 4.7 - Yes CTR CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-25 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 37 1,1,2,2-Tetrachloroethane µg/L 9 <0.5 0.17 - Ud CTR Tetrachloroethylene (aka Tetrachloroethene) µg/L 7 <0.5 0.8 - No CTR 39 Toluene µg/L 9 <0.5 150 - No CA Prim. MCL 40 1,2-Trans-Dichloroethylene µg/L 7 <0.005 10 - No CA Prim. MCL 41 1,1,1-Trichloroethane µg/L 9 <0.5 200 - No CA Prim. MCL 42 1,1,2-Trichloroethane µg/L 9 <0.5 0.6 - No CTR 43 Trichloroethylene (aka Trichloroethene) µg/L 7 <0.5 2.7 - No CTR 44 Vinyl Chloride µg/L 9 <0.5 0.5 - No CA Prim. MCL 45 2-Chlorophenol µg/L 8 <2.0 120 - No CTR 46 2,4-Dichlorophenol µg/L 8 <2.0 93 - No CTR 47 2,4-Dimethylphenol µg/L 8 <1.0 540 - No CTR 48 4,6-dinitro-o-resol (aka 2-methyl-4,6- Dinitrophenol aka 4,6-Dinitro-2- methylphenol) µg/L 7 <1.0 13.4 - No CTR 49 2,4-Dinitrophenol µg/L 8 <5.0 70 - No CTR 50 2-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 51 4-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 52 3-Methyl-4-Chlorophenol (aka P-chloro-m-resol aka 4-Chloro-3- methylphenol) µg/L 8 <1.0 No Criteria - Uc No criteria 53 Pentachlorophenol µg/L 34 2 0.28 - Yes CTR 54 Phenol, Single Compound µg/L 1 <1.0 1 - No BP 55 2,4,6-Trichlorophenol µg/L 8 <1.0 2.1 - No CTR 56 Acenaphthene µg/L 8 <1.0 1200 - No CTR 57 Acenaphthylene µg/L 8 <1.0 No Criteria - Uc No criteria 58 Anthracene µg/L 8 <1.0 9600 - No CTR CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-26 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 59 Benzidine µg/L 8 <1.0 0.00012 - Ud CTR 60 Benzo(a)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 61 Benzo(a)Pyrene µg/L 9 <0.1 0.0044 - Ud CTR 62 Benzo(b)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 63 Benzo(ghi)Perylene µg/L 8 <1.0 No Criteria - Uc No criteria 64 Benzo(k)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 65 Bis(2- Chloroethoxy)Methane µg/L 8 <1.0 No Criteria - Uc No criteria 66 Bis(2-Chloroethyl)Ether µg/L 8 <1.0 0.031 - Ud CTR 67 Bis(2-Chloroisopropyl)Ether µg/L 8 <1.0 1400 - No CTR 68 Bis(2-Ethylhexyl) Phthalate (aka Di(2-ethylhexyl) Phthalate) µg/L 9 <2.0 1.8 - Ud CTR 69 4-Bromophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 70 Butylbenzyl Phthalate µg/L 8 <1.0 3000 - No CTR 71 2-Chloronaphthalene µg/L 8 <1.0 1700 - No CTR 72 4-Chlorophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 73 Chrysene µg/L 8 <1.0 0.0044 - Ud CTR 74 Dibenzo(a,h)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 75 1,2-Dichlorobenzene µg/L 10 <0.5 600 - No CA Prim. MCL 76 1,3-Dichlorobenzene µg/L 9 <0.5 400 - No CTR 77 1,4-Dichlorobenzene µg/L 10 <0.5 5 - No CA Prim. MCL 78 3,3 Dichlorobenzidine µg/L 8 <1.0 0.04 - Ud CTR 79 Diethyl Phthalate µg/L 8 <1.0 23000 - Ud CTR 80 Dimethyl Phthalate µg/L 8 <1.0 313000 - No CTR 81 Di-n-Butyl Phthalate µg/L 8 <1.0 2700 - No CTR 82 2,4-Dinitrotoluene µg/L 8 <1.0 0.11 - Ud CTR 83 2,6-Dinitrotoluene µg/L 8 <1.0 No Criteria - Uc No criteria 84 Di-n-Octyl Phthalate µg/L 8 <1.0 No Criteria - Uc No criteria CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-27 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 85 1,2-Diphenylhydrazine µg/L 8 <1.0 0.04 - Ud CTR 86 Fluoranthene µg/L 8 <1.0 300 - No CTR 87 Fluorene µg/L 8 <1.0 1300 - No CTR 88 Hexachlorobenzene µg/L 8 <1.0 0.00075 - Ud CTR 89 Hexachlorobutadiene µg/L 8 <1.0 0.44 - Ud CTR 90 Hexachlorocyclopentadiene µg/L 8 <1.0 50 - No CA Prim. MCL 91 Hexachloroethane µg/L 8 <1.0 1.9 - No CTR 92 Indeno(1,2,3-cd)Pyrene µg/L 8 <1.0 0.0044 - Ud CTR 93 Isophorone µg/L 8 <1.0 8.4 - No CTR 94 Naphthalene µg/L 8 <1.0 No Criteria - Uc No criteria 95 Nitrobenzene µg/L 8 <1.0 17 - No CTR 96 N-Nitrosodimethylamine µg/L 35 <0.001 0.00069 - No CTR 97 N-Nitrosodi-n-Propylamine µg/L 8 <1.0 0.005 - Ud CTR 98 N-Nitrosodiphenylamine µg/L 8 <1.0 5 - No CTR 99 Phenanthrene µg/L 8 <1.0 No Criteria - Uc No criteria 100 Pyrene µg/L 8 <1.0 960 - No CTR 101 1,2,4-Trichlorobenzene µg/L 9 <0.5 5 - No CA Prim. MCL 102 Aldrin µg/L 9 <0.005 0.00013 - Ud CTR 103 alpha-BHC µg/L 8 <0.005 0.0039 - Ud CTR 104 beta-BHC µg/L 8 <0.005 0.014 - No CTR 105 gamma-BHC µg/L 10 <0.005 0.019 - No CTR 106 delta-BHC µg/L 8 <0.005 No Criteria - Uc No criteria 107 Chlordane µg/L 9 <0.047 0.00057 - Ud CTR 108 4,4'-DDT µg/L 8 <0.005 0.00059 - Ud CTR 109 4,4'-DDE µg/L 8 <0.005 0.00059 - Ud CTR 110 4,4'-DDD µg/L 8 <0.005 0.00083 - Ud CTR 111 Dieldrin µg/L 9 <0.005 0.00014 - Ud CTR 112 alpha-Endosulfan µg/L 8 <0.005 0.056 - No CTR 113 beta-Endolsulfan µg/L 8 <0.005 0.056 - No CTR 114 Endosulfan Sulfate µg/L 8 <0.005 110 - No CTR 115 Endrin µg/L 10 <0.005 0.036 - No CTR CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-28 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 116 Endrin Aldehyde µg/L 7 <0.005 0.76 - No CTR 117 Heptachlor µg/L 10 <0.005 0.00021 - Ud CTR 118 Heptachlor Epoxide µg/L 10 <0.005 0.00011 - Ud CTR 119- 125 PCBs sum µg/L 2 <0.5 0.00017 - Ud CTR 126 Toxaphene µg/L 9 <0.24 0.0002 - Ud CTR Non-Priority Pollutants Drinking Water Quality Objectives Aluminum µg/L 9 150 200 - No CA Sec. MCL Barium µg/L 9 42.9 1000 - No CA Prim. MCL Fluoride mg/L 9 0.7 1 - No BP Nitrate, Total (as N) mg/L 151 51.7 10 8.1 Yes EPA Prim. MCL Nitrate + Nitrite (as N) mg/L 7 43.4 10 - Yes CA Prim. MCL Nitrite, Total (as N) mg/L 106 5.1 1 <0.1 Yes CA Prim. MCL Methyl-tert-butyl ether µg/L 9 <1.0 5 - No CA Sec. MCL Styrene µg/L 9 <0.5 100 - No CA Prim. MCL Alachlor µg/L 9 <0.1 2 - No CA Prim. MCL Atrazine µg/L 9 <0.1 1 - No CA Prim. MCL Bentazon µg/L 9 <2.0 18 - No CA Prim. MCL Carbofuran µg/L 9 <5.0 18 - No CA Prim. MCL 2,4-D µg/L 9 5 70 - No CA Prim. MCL Dalapon µg/L 9 <10.0 200 - No CA Prim. MCL Dibromochloropropane (aka 1,2-Dibromo-3- Chloropropane) µg/L 8 <0.01 0.2 - No CA Prim. MCL Di(2-ethylhexyl)adipate µg/L 9 <5.0 400 - No CA Prim. MCL Dinoseb µg/L 9 <1.0 7 - No CA Prim. MCL Diquat µg/L 9 <2.0 20 - No CA Prim. MCL Endothall µg/L 9 <40 100 - No CA Prim. MCL Ethylene Dibromide (aka 1,2-Dibromoethane) µg/L 8 <0.02 0.05 - No CA Prim. MCL CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-29 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Glyphosate µg/L 9 <20.0 700 - No CA Prim. MCL Methoxychlor µg/L 10 <0.1 30 - No CA Prim. MCL Molinate µg/L 9 <0.1 20 - No CA Prim. MCL Oxamyl µg/L 9 <5.0 50 - No CA Prim. MCL Picloram µg/L 9 <1.0 500 - No CA Prim. MCL Simazine µg/L 9 <0.1 4 - No CA Prim. MCL Thiobencarb µg/L 9 <0.1 70 - No CA Prim. MCL 2,4,5-TP (Silvex) µg/L 9 <1.0 50 - No CA Prim. MCL Trichlorofluoromethane µg/L 9 <0.5 150 - No CA Prim. MCL 1,1,2-Trichloro-1,2,2- Trifluoroethane µg/L 3 <0.5 1200 - No CA Prim. MCL Xylenes µg/L 9 <0.5 1750 - No CA Prim. MCL Methylene blue activated substances (MBAS) µg/L 8 800 200 - Yes BP Un-ionized Ammonia (as N) mg/L [5] [5] 0.025 - Yes[5] BP Board 3 Basin Plan Water Quality Objectives for Agricultural Water Use Boron, Total µg/L 7 260 750 - No BP Cobalt, Total µg/L 7 4.0 50 - No BP Iron, Total µg/L 8 520 5000 - No BP Lithium, Total µg/L 7 14 2500d - No BP Manganese, Total µg/L 8 42.8 200 - No BP Molybdenum, Total µg/L 7 17 10 - Yes BP Vanadium, Total µg/L 7 5 100 - No BP San Luis Obispo Creek Sub-Area Surface Water Quality Objectives Total Dissolved Solids mg/L 38 990 650 470- 750[6] Yes BP Chloride mg/L 39 209 100 31- 92[6] Yes BP Sulfate, Total, (as SO4) mg/L 6 142 100 - Yes BP Sodium mg/L 35 181 50 29- 72[6] Yes BP [1] Number of data points available for the RPA. [2] If there is a detected value, the highest reported value is summarized in the table. If there are no detected values, if available, the lowest MDL is summarized in the table. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-30 [3] RPA Results: = Yes, if MEC > WQO/WQC, or B > WQO/WQC and MEC is detected; = No, if MEC and B are < WQO/WQC or all effluent data are undetected; = (Uc) Undetermined, if no criteria have been promulgated; = (Ud) Undetermined, for lack of data. As described in section 1.3 in the SIP, if monitoring results show non-detect for all samples of a pollutant and if all reported detection limits of the pollutant in the effluent are greater than or equal to the C value, the RWQCB shall require additional monitoring for the pollutant in place of a water quality-based effluent limitation. For pollutants with a result of Ud, additional monitoring is established through this permit. [4] Basis of Most Stringent Criteria CTR - California Toxics Rule’ CA Prim. MCL - California Primary MCL CA Sec. MCL - California Secondary MCL EPA Prim. MCL - EPA Primary MCL EPA Sec. MCL - EPA Secondary MCL NAWQC - National Ambient Water Quality Criteria BP - Central Coast Regional Board 2019 Basin Plan SWRCB 2017-0027 - Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California—Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. [5] The reasonable potential for the effluent to exceed the 2019 Basin Plan water quality objective for San Luis Obispo Creek for un-ionized ammonia is based on 93 concurrent upstream (RSW-004) and downstream (RSW-005) monitoring data results from December 2014 through April 2020. [6] Range of measured values. The 2019 Basin Plan Water Quality Objective for this pollutant is an annual mean. 4.3.4. WQBEL Calculations As detailed in Table F-6, reasonable potential has been determined for mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, total nitrate (as N), nitrate + nitrite (as N), total nitrite (as N), un- ionized ammonia (as N), methylene blue activated substances (MBAS), total molybdenum, total dissolved solids (TDS), sulfate, sodium, and chloride. The following example demonstrates how WQBELs were established for this Order for chlorodibromomethane. Step 1: For each water quality criterion/objective, an effluent concentration allowance (ECA) is calculated from the following equation to account for dilution and background levels of each pollutant. ECA = C + D (C – B), when C > B, and ECA = C when C ≤ B, Where, C = the applicable water quality criterion (adjusted for receiving water hardness and expressed as total recoverable metal, if applicable). CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-31 D = the dilution credit (here D = 0, as the Central Coast Water Board has no information with which to justify credit for dilution). B = the background concentration As discussed above, for this Order, dilution was not allowed; therefore: ECA = C For chlorodibromomethane, the applicable water quality criteria are: ECAHuman Health = 0.401 μg/L Step 2: For each ECA based on an aquatic life criterion, the long-term average discharge condition (LTA) is determined by multiplying the ECA times a factor (multiplier), which adjusts the ECA to account for effluent variability. The multiplier varies depending on the coefficient of variation (CV) of the data set and whether it is an acute or chronic criterion/objective. Table 1 of the SIP provides pre-calculated values for the multipliers based on the value of the CV. When the data set contains less than 10 sample results, or 80 percent or more of the data are reported as non-detect (ND), the CV is set equal to 0.6. Derivation of the multipliers is presented in Section 1.4 of the SIP. LTAacute = ECAacute x Multiplieracute 99 LTAchronic= ECAchronic x Multiplierchronic 99 Typically, historic effluent data is used to develop the acute and chronic LTA using equations provided in Section 1.4, Step 3 of the SIP (Table 1 of the SIP also provides this data up to three decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the development of this permit and LTA for acute and chronic were unnecessary to calculate. Step 3: WQBELs, including an AMEL and a MDEL are calculated using the most limiting (the lowest) LTA. The LTA is multiplied times a factor that accounts for averaging periods and exceedance frequencies of the effluent limitations, and for the AMEL, the effluent monitoring frequency. Here, the sampling frequency is set equal to 1 (n = 1). The 99th percentile occurrence probability was used to determine the MDEL multiplier and a 95th percentile occurrence probability was used to determine the AMEL multiplier. Table 2 of the SIP presents the MDEL and AMEL multipliers as a function of the CV. When the data set contains less than 10 sample results, or when 80 percent or more of the data set is reported as non-detect (ND), the CV is set equal to 0.6. Otherwise, the CV is calculated as the standard deviation divided by the mean. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-32 No. of Samples No. of Samples Per Month (n) CV 73 1 0.6 Step 4: Calculate the WQBELs by multiplying the LTA by a factor (multiplier). WQBELs are expressed as AMEL and MDEL. The multiplier is a statistically based factor that adjusts the LTA for the averaging periods and exceedance frequencies of the criteria/objectives and the effluent limitations. The value of the multiplier varies depending on the probability basis, the coefficient of variation (CV) of the data set, the number of samples (for AMEL) and whether it is a monthly or daily limit. Table 2 of the SIP provides pre-calculated values for the multipliers based on the value of the CV and the number of samples. Equations to develop the multipliers in place of using values in the tables are provided in Section 1.4, Step 5 of the SIP and will not be repeated here. AMELaquatic life = LTA x AMELmultiplier 95 MDELaquatic life = LTA x MDELmultiplier 99 AMEL multipliers are based on a 95th percentile occurrence probability, and the MDEL multipliers are based on the 99th percentile occurrence probability. If the number of samples is less than four (4), the default number of samples to be used is four (4). Equations provided in Section 1.4, Step 5 of the SIP are used to develop the AMEL and MDEL for aquatic life using (Table 2 of the SIP also provides this data up to two decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the development of this permit and AMEL and MDEL for aquatic life were unnecessary to calculate. Calculation of human health AMEL and MDEL: Step 5: For the ECA based on human health, set the AMEL equal to the ECAhuman health AMELhuman health = ECAhuman health For chlorodibromomethane: AMELhuman health = 0.401 μg/L Step 6: Calculate the MDEL for human health by multiplying the AMEL by the ratio of the MultiplierMDEL to the MultiplierAMEL. Table 2 of the SIP provides pre-calculated ratios to be used in this calculation based on the CV and the number of samples. MDELhuman health = AMELhuman health x (MultiplierMDEL / MultiplierAMEL) For chlorodibromomethane the following data were used to develop the MDELhuman health: No. of Samples Per Month CV MultiplierMDEL 99 MultiplierAMEL 95 Ratio CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-33 1 0.6 3.11 1.55 2.01 MDELhuman health = 0.401 μg/L x 2.01 = 0.806 μg/L Step 7: Select the lower of the AMEL and MDEL based on aquatic life and human health as the water-quality based effluent limit for the Order. For chlorodibromomethane, the AMELhuman health and MDELhuman health were 0.401 μg/L and 0.806 μg/L respectively. Thus, the human health criteria-based effluent limitations were more stringent and were considered in the Order. 4.3.4.1 Constituents with Reasonable Potential 4.3.4.1.1 Mercury. The RPA used effluent data from December 2014 through December 2022 and showed that there was a reasonable potential for the discharge to exceed the total recoverable mercury criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.012 µg/L and an MDEL of 0.024 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total recoverable mercury. 4.3.4.1.2 Chlorodibromomethane. The previous Order established an AMEL of 0.40 µg/L and an MDEL of 1.0 µg/L for chlorodibromomethane (dibromochloromethane). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chlorodibromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.4 µg/L and an MDEL of 0.81 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chlorodibromomethane. 4.3.4.1.3 Chloroform. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chloroform criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chloroform. 4.3.4.1.4 Dichlorobromomethane. The previous Order established an AMEL of 0.56 µg/L and an MDEL of 1.0 µg/L for dichlorobromomethane. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the dichlorobromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.56 µg/L and an MDEL of 0.96 µg/L have been established in this permit. Effluent and receiving water CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-34 monitoring and reporting requirements have also been established for dichlorobromomethane. 4.3.4.1.5. Methylene Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the methylene chloride criteria; therefore, effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 4.7 µg/L and an MDEL of 9.45 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for methylene chloride. 4.3.4.1.6. Pentachlorophenol. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the pentachlorophenol criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for pentachlorophenol. 4.3.4.1.8. Nitrate and Nitrate + Nitrite. As previously discussed, an effluent limitation for total nitrate (as N) was established through the TMDL for nitrate-nitrogen discharges to San Luis Obispo creek and was retained from the previous permit. Additionally, an effluent limitation for total nitrite (as nitrogen) is established in this order. A separate effluent limitation has not been established for nitrate+nitrite. Nitrate+nitrite is the sum of nitrate and nitrite, and therefore is duplicative of the two established effluent limitations. 4.3.4.1.9. Nitrite. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the total nitrite (as N) criteria, and therefore an effluent limitation is established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 1.0 mg/L has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total nitrite (as N). 4.3.4.1.10. Methylene blue activated substances (MBAS). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the MBAS criteria of 0.2 mg/L from the 2019 Basin Plan. The 0.2 mg/L effluent limitation established in this order is equivalent to the most stringent water quality objective in the 2019 Basin Plan. Effluent and receiving water monitoring and reporting requirements have also been established for MBAS. 4.3.4.1.11 Un-ionized Ammonia. The 2019 Basin Plan includes a water quality objective for un-ionized ammonia (NH3) of 0.025 mg/L. The previous Order did not establish an effluent limitation for un-ionized ammonia. The previous Order incorporated the Basin Plan objective as a receiving water limitation. From December 2014 through April 2020, the Discharger collected 93 concurrent upstream (RSW-004) and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-35 downstream (RSW-005) samples to determine un-ionized ammonia concentrations in the receiving water. The effluent caused the receiving water to exceed the Basin Plan objective on 29 occasions. Reasonable potential was found for un-ionized ammonia, and an effluent limitation and monitoring requirement were established for un-ionized ammonia. The effluent limitation of 0.025 mg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. 4.3.4.1.12. Molybdenum. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the molybdenum criteria of 10 µg/L from the 2019 Basin Plan. An effluent limitation of 10 µg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for molybdenum. 4.3.4.1.13. Total Dissolved Solids. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the total dissolved solids criteria of 650 mg/L in the Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for total dissolved solids. 4.3.4.1.14. Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the chloride criteria of 100 mg/L from the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for chloride. 4.3.4.1.15. Sulfate. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sulfate criteria of 100 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sulfate. 4.3.4.1.16. Sodium. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sodium criteria of 50 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sodium. 4.3.4.2 Constituents with No Reasonable Potential As detailed in Table F-8, constituents that were analyzed and received a “No” in the “RPA Result” column did not have a reasonable potential to cause or contribute to an excursion above the 126 U.S. EPA priority toxic pollutants, title 22 MCLs, or any CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-36 numeric water quality objectives included in any State Water Board plans or the 2019 Basin Plan. WQBEL’s are not included in this Order for constituents that do not demonstrate reasonable potential to cause or contribute to an instream excursion of an applicable water quality objective; however monitoring for priority toxic and title 22 pollutants is established in this Order. Most constituents with no reasonable potential are not discussed in this order. This section provides a discussion on the constituent with no reasonable potential for which an effluent limitation has not been retained from the previous order. 4.3.4.2.1 N-nitrosodimethylamine. The previous Order included an AMEL of 0.00069 µg/L and an MDEL of 0.0014 µg/L for n-nitrosodimethylamine. Several sample results analyzed during 2016 showed effluent limitation exceedances. However, in a letter dated February 9, 2017, the Discharger provided additional information to the Central Coast Water Board describing that the cause of the apparent exceedances was due to the test method used to analyze the samples. The Minimum Level (ML) established for n-nitrosodimethylamine in Appendix 4 of the SIP is 5 µg/L for samples analyzed by gas chromatography/ mass spectrometry. The Discharger was using EPA Method 1625M, an “ultra-low-level” method, which is not an approved method in 40 CFR part 136 and is not appropriate for compliance monitoring. The Discharger notified the Central Coast Water Board of its plan to return to using EPA Method 625 to measure n- nitrosodimethylamine in the effluent instead of the “ultra-low-level” the Discharger used in 2016 (i.e., EPA Method 1625M). On May 15, 2017, the Central Coast Water Board provided a written response that concurred with the Discharger regarding the return to EPA Method 625 and that the n-nitrosodimethylamine effluent concentrations reported in 2016 should not have been reported as effluent limitation exceedances because results below the ML of 5 µg/L are not considered violations according to the SIP. The RPA used effluent data from December 2014 through December 2022 that was analyzed using the correct test method and found that there was not reasonable potential for an exceedance of a water quality objective. An effluent limitation of n- nitrosodimethylamine has not been retained for this Order. Additional discussion is included in section 4.4.1 Ant-Backsliding Requirements and section 4.4.1 Antidegradation Policies of this fact sheet. 4.3.5. Whole Effluent Toxicity (WET) Aquatic toxicity is the adverse response of aquatic organisms from exposure to chemical or physical agents, or their synergistic effects in effluent or ambient water. Acute aquatic toxicity refers to adverse response (typically lethality) from a short-term exposure. Chronic aquatic toxicity generally refers to longer exposure duration and measures of both lethal and sub-lethal adverse response. WET testing protects receiving waters from the aggregate toxic effect of a mixture of pollutants that may be present in effluent. The Basin Plan establishes a narrative WQO which states that all waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-37 Survival of aquatic organisms in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge or for another control water. The WET approach allows for protection of the narrative “no toxics in toxic amounts” criterion while implementing numeric criteria for toxicity. For compliance with the Basin Plan’s narrative toxicity objective and the 2022 Toxicity Provisions, this Order requires the Discharger to conduct WET testing for acute and chronic toxicity in accordance with the Test of Significant Toxicity (TST) statistical approach, as specified in section 5 of the MRP (Attachment E). 4.3.5.1. Test of Significant Toxicity (TST) In 2010, U.S. EPA endorsed the TST statistical hypothesis testing approach, described in the National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, as an improved hypothesis-testing tool to evaluate data from U.S EPA’s toxicity test methods. The TST hypothesis testing approach more reliably identifies toxicity—in relation to the chronic (0.25 or more) and acute (0.20 or more) mean responses of regulatory management concern—than the No Observed Effect Concentration (NOEC) hypothesis-testing approach previously used. On December 1, 2020, the State Water Board adopted Resolution No. 2020-0044, establishing the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries (ISWEBE Plan), and adopting statewide numeric WQOs for both acute and chronic toxicity and a program of implementation to control toxicity, which are collectively known as the Toxicity Provisions. The Toxicity Provisions, which were revised on October 5, 2021, standardized the regulation of aquatic toxicity for all non- oceanic surface waters.3 U.S. EPA’s Test of Significant Toxicity Design, or TST, approach is an essential component of the Toxicity Provisions as it forms the basis for utilizing numeric WQOs and acts as the primary means of determining compliance with WET effluent limitations. This Order requires application of the TST approach for statistical analysis of WET data. 4.3.5.1.1. Test of Significant Toxicity Design The TST null hypothesis (Ho) for acute toxicity is: “mean discharge IWC response ≤0.80 × mean control response”, where 0.80 is the regulatory management decision (RMD). The TST null hypothesis (Ho) for chronic toxicity is: “mean discharge IWC response ≤0.75 × mean control response”, where 0.75 is the RMD. The null hypotheses for acute and chronic toxicity described in the TST are assigned as numeric WQOs for acute and chronic toxicity in sections II.C.1 and II.C.2 of the Toxicity Provisions. A test result that rejects the null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The TST approach is a t-test (formally Student’s t- 3 The Toxicity Provisions were approved by the Office of Administrative Law on April 25, 2022, and by U.S. EPA on May 1, 2023. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-38 test), a statistical analysis comparing two sets of replicate observations—in the case of WET tests, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”)). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month, or in consecutive calendar months, result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be reported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). Compliance with the toxicity limitation is demonstrated by rejecting the null hypothesis and reporting “Pass”. When the toxicity test results in a “Fail” the Discharger must initiate accelerated monitoring as specified in section 5.3 of the MRP. After accelerated monitoring, if conditions of chronic toxicity are found to persist, the Discharger will be required to conduct a TRE, as described in section 5.4 of the MRP. See section III.B.3 of the Toxicity Provisions for a detailed step-by-step description of the TST statistical method. 4.3.5.2. WET Reasonable Potential Analysis To determine the need for acute and/or chronic toxicity effluent limitations, the Central Coast Water Board conducted a RPA using the TST approach. In conducting the RPA, the Central Coast Water Board considered and evaluated all acute and chronic toxicity data generated during the previous permit term since the data is representative of the actual effluent quality from the Facility. Reasonable potential exists if any of the acute or chronic toxicity tests result in a “Fail” or if the percent effect at the IWC is greater than 10 percent. The IWC for Discharge Point 001 is 100 percent effluent. The Discharger conducted eight acute and 26 chronic toxicity tests using the species Pimephales promelas between October 2015 and October 2022, as shown in Table F- 10 below. Analysis using the TST approach concluded that the Discharger failed zero acute toxicity tests, and 14 chronic toxicity tests, representing a fail rate of 54 percent. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-39 After extensive City staff and consultant review, summarized in the Toxicity Reduction Evaluation Workplan Conclusion report submitted to the Central Coast Regional Water Quality Control Board on May 22, 2019, all Effluent 001 sampling events from October 2016 to October 2018 exhibited at least one of the three qualifying data interpretations of sporadic mortality, suggesting biological interference was the cause of observed toxicity. The Central Coast Water Board reviewed the TRE Workplan and maintained that the failed chronic test results would remain on record. These chronic toxicity test results were used to conclude that the discharge has reasonable potential to cause or contribute to an exceedance of chronic toxicity WQOs and that the discharge is subject to chronic toxicity effluent limitations. In addition, section III.C.5.c. of the Toxicity Provisions requires establishment of chronic toxicity effluent limitations if a POTW is authorized to discharge at a rate equal to or greater than 5.0 MGD and is required to have a pretreatment program by the terms of 40 CFR section 403.8(a). The permitted flow rate for the Facility is 5.4 MGD, and the Discharger is required to have a pretreatment program. Therefore, based on the determination of the RPA, and requirements contained in the Toxicity Provisions, the Order establishes MDEL and MMEL effluent limitations for chronic toxicity. Table F-9. Summary of Acute and Chronic Toxicity Test Results Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 10/6/2015 Pass 2.50 Survival Acute 10/4/2016 Pass 0.00 Survival Acute 10/3/2017 Pass 10.00 Survival Acute 10/30/2018 Pass 0.00 Survival Acute 10/15/2019 Pass 7.50 Survival Acute 10/28/2020 Pass 0.00 Survival Acute 10/5/2021 Pass 0.00 Survival Acute 10/4/2022 Pass 0.00 Survival Acute 10/6/2015 Pass 8.68 Growth Chronic 10/6/2015 Pass 6.78 Survival Chronic 10/4/2016 Pass -13.56 Growth Chronic 10/4/2016 Pass 13.33 Survival Chronic 10/3/2017 Fail 31.69 Growth Chronic 10/3/2017 Fail 40.68 Survival Chronic 10/24/2017 Fail 49.63 Growth Chronic 10/24/2017 Fail 68.33 Survival Chronic 11/28/2017 Pass 17.20 Growth Chronic 11/28/2017 Pass 10.91 Survival Chronic 12/12/2017 Fail 43.78 Growth Chronic 12/12/2017 Fail 58.33 Survival Chronic 8/21/2018 Fail 19.95 Growth Chronic 8/21/2018 Fail 31.67 Survival Chronic 7/31/2018 Pass 14.48 Growth Chronic CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-40 Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 7/31/2018 Fail 34.48 Survival Chronic 10/30/2018 Pass 4.56 Growth Chronic 10/30/2018 Fail 18.33 Survival Chronic 10/15/2019 Pass -12.63 Growth Chronic 10/15/2019 Pass 1.75 Survival Chronic 10/28/2020 Pass -7.95 Growth Chronic 10/28/2020 Pass 0.00 Survival Chronic 10/5/2021 Pass -2.02 Growth Chronic 10/5/2021 Pass 0.00 Survival Chronic 10/4/2022 Pass 3.00 Growth Chronic 10/4/2022 Pass 0.00 Survival Chronic 4.3.5.3. Acute Aquatic Toxicity Although the Discharger reported no acute toxicity test failures from the eight acute toxicity tests conducted during the previous permit term, this permit retains annual effluent monitoring requirements for acute toxicity established in Order No. R3-2014- 0033 due to persistent failure of chronic toxicity tests during the previous permit term, which resulted in a required TRE being conducted. The Order implements federal guidelines (Regions 9 & 10 Guidance for Implementing Whole Effluent Toxicity Testing Programs) by requiring the Discharger to conduct acute species sensitivity testing as described in section 5 of the MRP (Attachment E). This Order requires the Discharger to conduct a screening test using a vertebrate and invertebrate species. After the screening test is completed, the Discharger is required to use the most sensitive species in future acute toxicity testing if the most sensitive species is found not to be Pimephales promelas. 4.3.6. Basin Plan and Bacteria Provisions 4.3.6.1. Bacteria Provisions. The Facility receives domestic wastewater and discharges to surface waters with the water contact recreation beneficial use (REC-1). Because of the nature of domestic wastewater, discharges from publicly owned treatment works with these discharge characteristics have the reasonable potential to cause or contribute to an exceedance of water quality criteria for bacteria. On August 7, 2018, the State Water Board adopted Part 3 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California – Bacteria Provisions and a Water Quality Standards Variance Policy (Bacteria Provisions), which establishes bacteria water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). Under the statewide Bacteria Provisions, the water quality objective protective of the REC-1 beneficial use is, in waters where the salinity is less than one part per thousand (ppth) 95 percent or more of the time: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-41 • The concentration of E. coli shall not exceed 100 colony forming units (cfu) per 100 milliliters (mL) as a six-week rolling geometric mean, calculated weekly. • A statistical threshold value (STV) of 320 cfu/100 mL for E. coli shall not be exceeded by more than 10 percent of the samples collected in a calendar month and calculated in a static manner. Order R3-2014-0033 established effluent limitations for coliform bacteria based on applicable water quality objectives in the Basin Plan for San Luis Obispo Creek. The bacteria water quality objectives in the Bacteria Provisions supersede numeric water quality objectives for bacteria for the REC-1 beneficial use contained in a water quality control plan prior to February 4, 2019. Because San Luis Obispo Creek salinity is less than one part per thousand (ppth) 95 percent or more of the time, this Order establishes E. coli effluent limitations for Discharge Point 001, based on the water quality objectives in the Bacteria Provisions, in place of the previous fecal coliform effluent limitations. 4.3.6.2. Dissolved Oxygen. In order to protect the beneficial uses of San Luis Obispo Creek, Order R3-2014-0033 retained an effluent limit for dissolved oxygen, prohibiting the discharge from containing a dissolved oxygen concentration of less than 4.0 mg/L or so low that it adversely affects beneficial uses. 4.3.6.3. Nitrate. San Luis Obispo Creek is included on the 303(d) List as impaired for nutrients. Central Coast Water Board Resolution R3-2005-0106 established TMDLs for nitrate for discharges to San Luis Obispo Creek. Due to federal and State anti- backsliding regulations, nitrate remains a pollutant of concern for this discharge and the monthly average effluent limitation of 10 mg/L as N is retained from the previous Order. 4.3.6.4. pH. Federal regulations, 40 CFR 133, establish technology-based effluent limitations for pH. The secondary treatment standards require the pH of the effluent to be no lower than 6.0 and no greater than 9.0 standard units. However, the Basin Plan establishes a WQO for pH of between 6.5 to 8.3 standard units for the protection of receiving waters with the beneficial use of Municipal and Domestic Supply (MUN), Agricultural Supply (AGR), and Water Recreation (REC1 and REC2). The Basin Plan establishes a WQO for pH between 7.0 to 8.5 standard units for the beneficial use of Freshwater Habitat (COLD and WARM) and Fish Spawning (SPWN). The previous Order established an effluent limitation of 6.5 to 8.3. However, since San Luis Obispo Creek has MUN, AGR, REC1, REC2, COLD, WARM, and SPWN beneficial uses, a pH effluent limitation of 7.0 to 8.3 is appropriate in order to protect all beneficial uses. This Order updates the previous effluent limitation of 6.5 to 8.3 from the previous Order, based on the water quality objective for the Municipal and Domestic Supply (MUN) beneficial use. For the protection of the COLD beneficial use, this Order applies a receiving water limitation of 7.0 to 8.3, with no change in normal ambient pH levels above 0.5. 4.3.6.5. Oil and Grease. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works has the reasonable potential to cause or contribute to an exceedance of water quality criteria for oil and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-42 grease. The Basin Plan establishes a narrative effluent limitation for oil and grease, which states, “Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. The previous Order contained an AMEL and MDEL of 5.0 mg/L and 10 mg/L, respectively. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.3.6.6. Floating Material. Discharge of treated wastewater through Discharge Point No. 001 shall not contain floating material, including solids, liquids, foams, and scum in concentrations that cause nuisance or adversely affect beneficial uses. This effluent limitation is consistent with the Basin Plan. 4.3.6.7. Settleable Solids. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works have the reasonable potential to cause or contribute to an exceedance of water quality criteria for settleable solids. The Basin Plan establishes a narrative effluent limitation for settleable solids, which states, “Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. The previous Order contained an average monthly effluent limitation (AMEL) of 0.1 mL/L. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.4. Final Effluent Limitation Considerations 4.4.1. Anti-Backsliding Requirements Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. 122.44(l) prohibit backsliding in NPDES permits. These anti-backsliding provisions require effluent limitations in a reissued permit to be as stringent as those in the previous permit, with some exceptions where limitations may be relaxed. All effluent limitations in this Order are at least as stringent as the effluent limitations in the previous Order. An effluent limitation for n-nitrosodimethylamine has not been retained from the previous Order because current data analysis shows no reasonable potential. The elimination of this WQBEL is consistent with the exception to the CWA's anti-backsliding requirements expressed at §402 (0)(2)(B)(i) of the Act, which allows a reissued permit to include less stringent limitations when information is available that was not available at the time of permit issuance (other than revised regulations, guidance, or test methods), and that would have justified the application of a less stringent effluent limitation at the time of permit issuance. The removal of the limitation of n- nitrosodimethylamine is based on new data, which was generated during the term of previous Order, and which demonstrates no reasonable potential for discharges from the Facility to cause or contribute to exceedances of applicable WQOs for this pollutant. Therefore, effluent limitations for these pollutants from the previous Order are not retained in this Order. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-43 4.4.2. Antidegradation Policies 40 CFR section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal antidegradation policy. On October 28, 1968, the State Water Board established California’s antidegradation policy when it adopted Resolution Number 68-16, Statement of Policy with Respect to Maintaining the Quality of the Waters of the State. Resolution Number 68-16 requires that existing water quality be maintained unless degradation is justified based on specific findings. The State Water Board has, in State Water Board Order Number 86-17 and an October 7, 1987 guidance memorandum, interpreted Resolution Number 68-16 to be fully consistent with the federal antidegradation policy contained in 40 CFR section 131.12. Similarly, CWA section 303(d)(4)(B) and 40 CFR section 131.12 require that all permitting actions be consistent with the federal antidegradation policy. Together, the state and federal antidegradation policies are designed to ensure that a water body will not be degraded resulting from the permitted discharge. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The renewal of this NPDES permit is consistent with the anti-degradation policy because it is not expected to allow degradation of receiving water quality. No reduction in the existing level of wastewater treatment is anticipated. In addition, the renewal of the NPDES permit will not lower the surface water quality because the conditions in this Order are at least as stringent as the previous permit except for limits described in section 4.4.1 of the Fact Sheet. Specifically, the removal of the final effluent limitation for n-nitrosodimethylamine is consistent with the antidegradation policy because the discharge did not exhibit reasonable potential to exceed the water quality objective, and it is not expected to degrade the water quality of the receiving water. Effluent and receiving water monitoring for this pollutant continue to be required under this Order to ensure effluent and receiving water concentrations do not exceed the objective. 4.4.3. Stringency of Requirements for Individual Pollutants This Order contains both technology-based and water quality-based effluent limitations for individual pollutants. The technology-based effluent limitations consist of restrictions on BOD and TSS. This Order’s technology-based pollutant restrictions implement the minimum applicable federal technology-based requirements. In addition, this Order contains effluent limitations more stringent than the minimum federal technology-based requirements that are necessary to meet water quality standards. For pH, BOD, and TSS both technology-based effluent limitations and water quality-based effluent limitations are applicable. The more stringent of these effluent limitations are implemented by this Order. These limitations are not more stringent than required by the CWA. Water quality-based effluent limitations have been derived to implement water quality objectives that protect beneficial uses. Both the beneficial uses and the water quality objectives have been approved pursuant to federal law and are the applicable federal water quality standards. To the extent that toxic pollutant water CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-44 quality-based effluent limitations were derived from the CTR, the CTR is the applicable standard pursuant to 40 C.F.R. 131.38. The procedures for calculating the individual water quality-based effluent limitations for priority pollutants are based on the CTR implemented by the SIP, which was approved by U.S. EPA on May 18, 2000. Any water quality objectives and beneficial uses submitted to U.S. EPA prior to May 30, 2000, but not approved by U.S. EPA before that date, are nonetheless “applicable water quality standards for purposes of the CWA” pursuant to 40 C.F.R. 131.21(c)(1). Collectively, this Order’s restrictions on individual pollutants are no more stringent than required to implement the requirements of the CWA. 4.4.4. Summary of Final Effluent Limitations 4.4.4.1. Effluent Limitations. The following effluent limitations are applicable to the discharge of disinfected tertiary treated wastewater from the Facility at Discharge Point No. 001. Table F-10. Final Effluent Limitations – Discharge Point EFF-001 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1275 2,125 - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - TSS lbs/day[1] 425 1,275 3,190 - - - pH[2],[3] standard units - - - 6.5 8.3 - Oil and Grease mg/L 5 - 10 - - - CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-45 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - Dissolved Oxygen mg/L - - - 4.0 - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.012 - 0.024 - - - Chlorodibromomethane (Dibromochloromethane) µg/L 0.401 - 0.81 - - - Chloroform µg/L 60 - 120.6 - - - Dichlorobromomethane (Bromodichloromethane) µg/L 0.56 - 0.96 - - - Methylene Chloride µg/L 4.7 - 9.45 - - - Pentachlorophenol µg/L 0.28 - 0.56 - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - Nitrite, Total mg/L 1 - - - - - Un-ionized Ammonia mg/L 0.025 - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - Molybdenum mg/L 0.01 - - - - - Total Dissolved Solids mg/L 650 - - - - - Chloride mg/L 100 - - - - - CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-46 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Sodium mg/L 50 - - - - - Sulfate mg/L 100 - - - - - Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail ” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 6.5-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 6.5-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0-9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 6.5-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-47 • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30- day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in-stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP-Attachment E). 4.5. Interim Effluent Limitations – Not Applicable 4.6. Land Discharge Specifications – Not Applicable 4.7. Recycling Specifications This Order allows the production and onsite use of disinfected tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements in the State Water Board’s Recycled Water Policy, and those established by DDW at title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. This Order includes water reclamation requirements for the Facility pursuant to the State Water Board’s Division of Drinking Water recommendations submitted to the Central Coast Water Board. This Order requires the Discharger to adhere to the requirements outlined in section 4.3 and any additional conditions pursuant to specifications in updated title 22 engineering reports approved by the State Water Board’s Division of Drinking Water. 4.8. Point of Compliance for Effluent Limitations 4.8.1. The Discharger must comply with the effluent limitations established in this order at location EFF-001. The facility includes a long concrete pipe that sends treated effluent from the facility to San Luis Obispo Creek. In previous permits, the discharge was monitored at the end of the pipe, just before it mixes with San Luis Obispo Creek. Due to safety and cost concerns, the Discharger requested to perform the majority of their compliance monitoring at the beginning of the pipe. The beginning of the pipe is referred to as EFF-001A and the end of the pipe is referred to as EFF-001B. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-48 5. RATIONALE FOR RECEIVING WATER LIMITATIONS 5.1. Surface Water Receiving water quality is a result of many factors, some unrelated to the discharge. This Order considers these factors and is designed to minimize the influence of the discharge on the receiving water. Specific water quality objectives established by the Basin Plan to meet this goal for all inland surface waters are included as receiving water limitations in section 5.1. of this Order. 6. RATIONALE FOR PROVISIONS 6.1. Standard Provisions Standard Provisions, which apply to all NPDES permits in accordance with 40 C.F.R. section 122.41, and additional conditions applicable to specified categories of permits in accordance with 40 C.F.R. section 122.42, are provided in Attachment D. The Discharger must comply with all standard provisions and with those additional conditions that are applicable under section 122.42. Sections 122.41(a)(1) and (b) through (n) of 40 C.F.R. establish conditions that apply to all state-issued NPDES permits. These conditions must be incorporated into the permits either expressly or by reference. If incorporated by reference, a specific citation to the regulations must be included in the Order. Section 123.25(a)(12) of 40 C.F.R. allows the state to omit or modify conditions to impose more stringent requirements. In accordance with 40 C.F.R. section 123.25, this Order omits federal conditions that address enforcement authority specified in 40 C.F.R. section 122.41(j)(5) and (k)(2) because the enforcement authority under the California Water Code is more stringent. In lieu of these conditions, this Order incorporates by reference California Water Code section 13387(e). 6.2. Special Provisions 6.2.1. Reopener Provisions The Order may be modified in accordance with the requirements set forth at 40 C.F.R. parts 122 and 124, to include appropriate conditions or limits based on newly available information, or to implement any, new state water quality objectives that are approved by the U.S. EPA. As effluent is further characterized through additional monitoring, and if a need for additional effluent limitations becomes apparent after additional effluent characterization, the Order will be reopened to incorporate such limitations. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential to cause, or contributes to an excursion above a SIP water quality objective. 6.2.2. Special Studies and Additional Monitoring Requirements 6.2.2.1. Whole Effluent Toxicity. The Basin Plan states, “All waters shall be maintained free of toxic substances in concentrations which are toxic to, or CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-49 which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board.” The Basin Plan further states, “Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality condition, shall not be less than that for the same waterbody in areas unaffected by the waste discharge…” and that effluent limitations based upon acute bioassays of effluent will be prescribed where appropriate. This permit establishes acute and chronic monitoring requirements, and chronic toxicity effluent limitations in accordance with the 2022 Toxicity Provisions, which incorporates the narrative objectives of the Basin Plan. The Order and MRP require the Discharger to conduct accelerated toxicity testing for exceedances of the acute toxicity WQOs, as described in the Toxicity Provisions, and/or chronic toxicity effluent limitations. If the accelerated testing demonstrates toxicity, the Discharger is required to submit a TRE Work Plan in accordance with U.S. EPA guidance, which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharge will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TIE process in accordance with the Work Plan if the results of toxicity testing exceed the effluent limitation or trigger for toxicity. 6.2.3. Best Management Practices and Pollution Prevention 6.2.3.1. Pollutant Minimization Program. The Discharger is required to minimize the discharge of pollutants consistent with the requirements of section 2.4.5.1 of the SIP. The goal of the Pollutant Minimization Program is to reduce all potential sources of a priority pollutant through pollutant minimization strategies to maintain the effluent concentration at or below water quality-based effluent limitations. 6.2.3.2. Salt and Nutrient Management Program. Section VI.C.3 of the previous Order required the Discharger to conduct a Salt Management Study to control levels of TDS, chloride, sodium, sulfate, and boron (collectively referred to as salts) in discharges from the Facility and attain applicable WQOs for salts in the San Luis Obispo Creek sub-basin of the Estero Bay Drainage Basin. Data from the term of the previous Order indicated the Facility has reasonable potential to cause or contribute to downstream impairment for salts loading. Therefore, in addition to effluent and receiving water monitoring for TDS, chloride, sulfate, boron and sodium, this Order requires the Discharger to continue to update and implement the Salt Management Program and provide annual reports. Additionally, the Discharger shall develop and implement a Nutrient Management Program as part of the Salt and Nutrient Management CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-50 Program, as discussed in section 6.3.3.1. of this Order, based on the Recycled Water Policy discussed in section 3.5.3. of this Fact Sheet. 6.2.4. Construction, Operation, and Maintenance Specifications 6.2.4.1 The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.2.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.2.5.1. Pretreatment. This Order contains pretreatment requirements consistent with applicable effluent limitations, national standards of performance, and toxic and performance effluent standards established pursuant to sections 208(b), 301, 302, 303(d), 304, 306, 307, 403, 404, 405, and 501 of the CWA, and amendments thereto. This permit contains requirements for the implementation of an effective pretreatment program pursuant to section 307 of the CWA; 40 CFR 35 and 403; and/or Title 23, CCR section 2233. 6.2.5.2. Collection System. The State Water Board issued General Waste Discharge Requirements for Sanitary Sewer Systems, Water Quality Order 2022-0103- DWQ (General Order) on December 6, 2022. The General Order requires public agencies that own or operate sanitary sewer systems with sewer lines one mile of pipe or greater to enroll for coverage and comply with the General Order. The General Order requires agencies to develop sanitary sewer management plans and report all sanitary sewer overflows, among other requirements and prohibitions. The General Order contains requirements for operation and maintenance of collection systems and for reporting and mitigating sanitary sewer overflows that are more extensive, and therefore, more stringent than the requirements under federal standard provisions. The Discharger obtained enrollment for regulation under the General Order 2022-0103-DWQ. 6.2.5.3. Resource Recovery from Anaerobically Digestible Material. Some POTWs choose to accept organic material such as food waste, fats, oils, and grease into their anaerobic digesters for co-digestion to increase production of methane and other biogases for energy production and to prevent such materials from being discharged into the collection system, which could cause sanitary sewer overflows. The California Department of Resources Recycling and Recovery has proposed an exemption from requiring Process Facility/Transfer Station permits where this activity is regulated under waste discharge requirements or NPDES permits. The proposed exemption is restricted to anaerobically digestible material that has been prescreened, slurried, and processed/conveyed in a closed system to be co-digested with regular POTW sludge. The proposed exemption requires that a POTW develop standard operating procedures for the proper handling, processing, tracking, and management of the anaerobically digestible material before it is received by the POTW. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-51 Standard operating procedures are required for POTWs that accept hauled food waste, fats, oil, and grease for injection into anaerobic digesters. The development and implementation of standard operating procedures for management of these materials is intended to allow the California Department of Resources Recycling and Recovery to exempt this activity from separate and redundant permitting programs. If the POTW does not accept food waste, fats, oil, or grease for resource recovery purposes, it is not required to develop and implement standard operating procedures. 6.2.5.4. Biosolids. Provisions regarding sludge handling and disposal ensure that such activities will comply with all applicable regulations. 40 C.F.R. part 503 sets forth U.S. EPA’s final rule for the use and disposal of biosolids, or sewage sludge, and governs the final use or disposal of biosolids. The intent of this federal program is to ensure that sewage sludge is used or disposed of in a way that protects both human health and the environment. U.S. EPA’s regulations require that producers of sewage sludge meet certain reporting, handling, and disposal requirements. As the U.S. EPA has not delegated the authority to implement the sludge program to the State of California, the enforcement of sludge requirements that apply to the Discharger remains under U.S. EPA's jurisdiction at this time. U.S. EPA, not the Central Coast Water Board, will oversee compliance with 40 C.F.R. part 503. 6.2.5.5. Discharges of Stormwater. Discharges of stormwater from POTWs with a design capacity greater than 1.0 MGD are applicable for coverage under General State Water Board Order No. 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Dischargers of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.2.6. Other Special Provisions 6.2.6.1. Recycled Water Policy Salt/Nutrient Management Plan. This Order requires the Discharger to develop and implement a Salt/Nutrient Management Plan. This requirement is based on the Recycled Water Policy. 6.2.6.2. Climate Change Adaptation Program. On March 7, 2017, the State Water Board adopted a resolution in recognition of the challenges posed by climate change that requires a proactive approach to climate change in all State Water Board actions, including drinking water regulation, water quality protection, and financial assistance (Resolution 2017- 0012). The resolution lays the foundation for a response to climate change that is integrated into all State Water Board actions, by giving direction to the State Water Board divisions and encouraging coordination with the regional water quality control boards. This Order requires the Discharger to implement and submit a Climate Change Adaptation Program. The Central Coast Water Board is addressing the threats of climate change and flooding by including provisions in new and reissued orders that ensure climate change mitigation and adaptation strategies are implemented. There is widespread scientific CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-52 consensus that climate change is occurring and will continue at an accelerating rate into the future. Extreme weather events, including drought, high-intensity precipitation, flooding, and extreme heat have occurred through much of California in recent years and are projected to increase in frequency, extent, or intensity due to climate change. Climate change has the potential to impact discharging facilities through inundation, storm impacts, and erosion, increasing the risk of accidental discharge that results in discharge permit violations. These events have significant implications for wastewater treatment and operations, such as increased corrosion, deposition of solids, infiltration, overflows, inundation of facilities, impairment of treatment processes, and disruption of power or electrical components. Due to the long-term nature of these risks, there is a need to avoid piecemeal or reactionary adaptation and instead undertake proactive, long-term planning with consideration of various adaptation strategies that both keep facilities safe, maintain safe discharging practices, and avoid impacts to resources. A description of the actions taken by the Discharger are described in section 2.5 – Response to Climate Change of this Order. These requirements are consistent with 40 CFR section 122.41(e), requiring permittees to ensure compliance through proper operation and maintenance of facilities, including installation and operation of appropriate auxiliary and backup facilities, and they are authorized pursuant to Water Code section 13383. (In re the City of Oceanside, Fallbrook Public Utilities Dist. And the Southern California Alliance of Publicly Owned Treatment Works, State Water Board Order WQ 2021- 0005, February 12, 2021 at p. 26.) The Los Angeles Water Board understands that the cost of preparing such a plan could be significant (estimated cost range of $25,000-$60,000), but "the costs of ensuring resilient infrastructure to protect water quality against the effects of climate change is warranted." (Fallbrook, at p. 27.) 6.2.7. Compliance Schedules – Not Applicable 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS CWA section 308 and 40 C.F.R. sections 122.41(h), (j)-(l), 122.44(i), and 122.48 require that all NPDES permits specify monitoring and reporting requirements. Sections 13267 and 13383 of the California Water Code also authorize the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements related to discharges to navigable waters or publicly owned treatment works, with section 13267 being the specific statute authorizing all such activities pertaining to the State Water Board’s Water Quality Control Policy for Recycled Water. The MRP, Attachment E of this Order, establishes monitoring, reporting, and recordkeeping requirements that implement federal and state requirements. The following provides the rationale for the inclusion of the monitoring and reporting requirements contained in the MRP for this facility to ensure compliance with Order requirements to ensure protection of water quality and beneficial uses. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-53 The Central Coast Water Board has considered the cost and need for monitoring and reporting generally in this NPDES permit. The discharger has provided the Central Coast Water Board with an estimation of its monitoring and reporting costs here, which are $226,860 for five years. Although the costs are significant, the costs are reasonable considering the nature of the wastewater discharge and because they result in critical data required under the Clean Water Act and which are needed to evaluate water quality generally, the impacts of the discharges on human and aquatic and benthic health, and water quality specifically, and to ensure that beneficial uses are protected. The requirements are generally comparable to other inland dischargers in the region. 7.1. Influent Monitoring In addition to influent flow monitoring, monitoring for BOD5 and TSS is required to determine compliance with the Order’s percent removal requirement for these pollutants and to assess plant performance. Influent monitoring requirements have been retained from the previous Order. 7.2. Effluent Monitoring Effluent monitoring is necessary to determine compliance with effluent limitations and evaluate compliance with applicable water quality objectives and criteria. Effluent monitoring requirements have been retained from the previous Order for Discharge Point 001, with some exceptions. Effluent monitoring for fecal coliform has been removed and replaced with E. coli monitoring to be consistent with the updated Bacteria Provisions. Effluent monitoring frequency has been increased in this Order to monthly for those pollutants with a reasonable potential to cause or contribute to an exceedance of a water quality standards and for which effluent limitations were established: mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, nitrite (as N), un- ionized ammonia, MBAS, total dissolved solids, sulfate, chloride, and sodium. Chronic toxicity monitoring has increased to monthly to reflect the requirements of the updated Toxicity Provisions. A quarterly effluent monitoring requirement has been established for hardness to assist with the next permit’s reasonable potential analysis. An annual effluent monitoring frequency has been established for results of the reasonable potential analysis and the 2019 Basin Plan objectives. 7.3. Whole Effluent Toxicity Testing Requirements Acute and chronic toxicity monitoring requirements and chronic toxicity effluent limitations have been established in this Order in accordance with the 2020 Toxicity Provisions in the ISWEBE Plan. An acute toxicity test is conducted over a short time period and measures mortality. A chronic toxicity test is conducted over a longer period of time and may measure mortality, reproduction, and growth. For this permit, chronic toxicity in the discharge was evaluated using U.S. EPA’s 2010 TST hypothesis testing approach and is expressed as “Pass” or “Fail” for the median monthly summary results and “Pass” or “Fail” and “Percent Effect” for each individual acute and chronic toxicity result. The chronic toxicity effluent limitations CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-54 protect the narrative WQO in the Basin Plan and comply with the requirement in the Toxicity Provisions to establish chronic effluent limitations for Facilities with permitted discharges greater than 5.0 MGD and a pretreatment program. This Order requires the Discharger to submit an updated TRE Work Plan submitted pursuant to Order No. R9-2014-0033 within 90 days of the effective date of the Order. The TRE Work Plan must describe steps the Discharger intends to follow if the effluent limitation for chronic toxicity is exceeded. If a routine acute and/or chronic toxicity test results in a “Fail” at the IWC, this Order requires the Discharger to conduct accelerated monitoring to determine the cause of the toxicity. A TRE is required when the Discharger has any combination of two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. In addition, if other information indicates toxicity (e.g., results of additional monitoring, fish kills, intermittent recurring toxicity, etc.), then the Central Coast Water Board may require a TRE. If a TRE is required, the Discharger is required to submit a detailed TRE Work Plan in accordance with U.S. EPA guidance which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharger will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TRE/TlE process in accordance with the submitted work plan if the results of toxicity testing exceed the effluent limitations for chronic toxicity. This Order retains annual acute toxicity monitoring requirements and establishes monthly chronic toxicity monitoring requirements based on the RPA determination for toxicity using the TST approach and the Toxicity Provisions. Refer to section 5 of the MRP (Attachment E). 7.4. Recycled Water Monitoring Recycled water monitoring is necessary to evaluate compliance with recycling specifications detailed in section 4.3 of this Order. 7.5. Receiving Water Monitoring 7.5.1. Surface Water Surface water receiving water requirements are necessary to evaluate compliance with water quality objectives, WQBELs, and the protection of beneficial uses. Surface water monitoring requirements have been retained from Order R3-2014-0033 for Discharge Point 001, with some changes in sampling frequency and additional constituents to monitor. Annual monitoring for CTR and title 22 pollutants has been included in this Order because it had not been required historically and is necessary to obtain the background (B) concentration data that will be used for the next permit’s reasonable potential analysis. Quarterly sampling of E.coli has been included in this Order to be consistent with the statewide Bacteria Provisions. Sampling frequency for flow, turbidity, color, pH, dissolved oxygen, and temperature have been decreased from weekly to CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-55 monthly due to personnel safety concerns at sampling locations in the creek. Monthly monitoring of these parameters will provide sufficient data of the receiving water. Quarterly monitoring of boron and monthly monitoring of TDS, chloride, sodium, and sulfate have been included in this Order to provide an understanding of salts concentrations in the receiving water. The addition of quarterly monitoring of hardness in this Order will assist with the next permit’s reasonable potential analysis. 7.5.2. Groundwater Consistent with the previous permit, groundwater monitoring requirements have not been included. 7.6. Other Monitoring Requirements 7.6.1. Discharge Monitoring Report-Quality Assurance (DMR-QA) Study Program Under the authority of section 308 of the CWA (33 U.S.C. 1318), U.S. EPA requires major and selected minor dischargers under the NPDES Program to participate in the annual DMR-QA Study Program. The DMR-QA Study Program evaluates the analytical ability of laboratories that routinely perform or support self-monitoring analyses required by NPDES permits. There are two options to satisfy the requirements of the DMR-QA Study Program: (1) The Discharger can obtain and analyze a DMR-QA sample as part of the DMR-QA Study; or (2) Per the waiver issued by U.S. EPA to the State Water Board, the Discharger can submit the results of the most recent Water Pollution Performance Evaluation Study from its own laboratories or its contract laboratories. A Water Pollution Performance Evaluation Study is similar to the DMR-QA Study. Thus, it also evaluates a laboratory’s ability to analyze wastewater samples to produce quality data that ensure the integrity of the NPDES Program. The Discharger shall ensure that the results of the DMR-QA Study or the results of the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board. The State Water Board’s Quality Assurance Program Officer will send the DMR-QA Study results or the results of the most recent Water Pollution Performance Evaluation Study to U.S. EPA’s DMR-QA Coordinator and Quality Assurance Manager. 7.6.2. Annual Volumetric Reporting of Wastewater and Recycled Water To establish a realistic estimate of statewide recycled water use and potential for increased recycled water use statewide, the Recycled Water Policy requires Dischargers to report the volume of treated wastewater and recycled water. The annual report will meet implementation needs of the Recycled Water Policy and fill data gaps for additional statewide water planning efforts. The burden and cost of preparing the report is reasonable and consistent with the interest of the state in maintaining water quality and developing alternative water supplies to increase water resiliency. The Discharger shall ensure that all volumetric reporting requirements from this Order are submitted in electronic format via the State Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. The State Water Board will evaluate CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-56 progress towards the recycled water goals in the Recycled Water Policy and evaluate the need to update the recycled water goals in the future based on consistent statewide data. 7.6.3. Biosolids/Sludge Monitoring Biosolids monitoring shall be reported in the annual report in accordance with 40 C.F.R. 503. Biosolids monitoring requirements have been retained from the previous Order. 7.6.4. Pretreatment Monitoring Pretreatment monitoring shall be reported in the annual report in accordance with requirements in 40 C.F.R. 403.8. Pretreatment monitoring requirements have been retained from the previous Order. 7.6.5. Salt and Nutrient Management Plan Reporting Salt and Nutrient Management Plan reporting requirements have been retained in this Order to help identify and reduce salt and nutrient loading in effluent. This salt/nutrient management report shall be included as a separate report from the annual report. 7.6.6. Discharge to Evaporation Ponds Reports of discharge to and from the Facility’s evaporation ponds are required pursuant to California Water Code section 13383. Any costs incurred with this reporting are expected to be minimal. The reporting is necessary to ensure compliance with the provisions of this Order, inform follow-up actions in the event of noncompliance with the provisions of this Order, and to protect human health and water quality. 8. CONSIDERATION OF NEED TO PREVENT NUISANCE AND WATER CODE SECTION 13241 FACTORS The requirements set forth in subsections 2.4 and 4.3 of this Order are included to implement state law only. These requirements are not required or authorized under the federal CWA; consequently, violations of these requirements are not subject to the enforcement remedies that are available for NPDES violations. As required by Water Code section 13263, the Central Coast Water Board has considered the need to prevent nuisance and the factors listed in Water Code section 13241 in establishing the state law provisions/requirements. The Central Coast Water Board finds, on balance, that the state law requirements in this Order are reasonably necessary to prevent nuisance and to protect beneficial uses identified in the Basin Plan, and the section 13241 factors are not sufficient to justify failing to protect those beneficial uses. 8.1. Need to prevent pollution or nuisance In establishing effluent limitations in this Order, the Central Coast Water Board has considered state law requirements to prevent pollution or nuisance as defined in section 13050, subdivisions (l) and (m), of the Water Code. The requirements in this CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-57 Order, including those set forth in subsections 2.4 and 4.3, will prevent pollution and nuisance. 8.2. Past, present, and probable future beneficial uses of water Chapter 2 of the Basin Plan identifies designated beneficial uses for water bodies in the Central Coast Region. Beneficial uses of water relevant to this Order are also identified above in sections 3.3.1 of this Fact Sheet. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order, including those set forth in sections 2.4 and 4.3 of this Order. Accordingly, the requirements herein protect and augment the past, present and probable future beneficial uses of the water. 8.3. Environmental characteristics of the hydrographic unit under consideration, including the quality of water available thereto The environmental characteristics of this watershed are discussed in the Basin Plan, as well as available in State of the Watershed reports and the State’s CWA Section 303(d) List of impaired waters. The environmental characteristics of the hydrographic unit, including the quality of available recycled water that may be produced as a result of this Order will be improved by compliance with the requirements of this Order. 8.4. Water quality conditions that could reasonably be achieved through the coordinated control of all factors which affect water quality in the area The water quality standards necessary to protect beneficial uses of San Luis Obispo Creek Sub-Basin of the Estero Bay Drainage Basin can reasonably be achieved through the coordinated control of all factors that affect water quality in the area, including the conservation of water and/or the production of recycled water authorized by this Order. For example, the water quality in the watershed and/or groundwater basin could be improved through the addition or use of recycled water authorized by this Order, which meets title 22 standards. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order. 8.5 Economic Considerations The Permittee presented evidence regarding cost of monitoring but did not present additional evidence concerning other economic considerations related to this Order, such as the benefits of producing recycled water and benefits resulting from protection of beneficial uses of San Luis Obispo Creek. The Central Coast Water Board has considered the economic impact of requiring certain provisions pursuant to state law, including the costs of conducting feasibility studies for recycling, conservation, and climate change. Any additional costs associated with producing any study are reasonably necessary to prevent nuisance and protect beneficial uses identified in the Basin Plan and to improve the water supply resiliency. The failure to consider conservation or recycled water could result in the loss of, or impacts to, beneficial uses, which would have a detrimental economic impact, particularly given the effects on beneficial uses and supplies of water from the drought and climate change. Economic considerations related to costs of CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-58 compliance are therefore not sufficient, in the Central Coast Water Board’s determination, to justify failing to prevent nuisance and protect beneficial uses. 8.6 The need for developing housing within the region The Central Coast Water Board does not anticipate that these state law requirements will adversely impact the need for housing in the area. To the contrary, this Order helps address the need for housing by controlling pollutants in discharges and by allowing the reuse and exportation of recycled water for use in the area. Both of these things will improve the quality of local surface and groundwater, as well as water supply generally. This may in turn increase the region’s capacity to support continued housing development. Therefore, the potential for developing housing in the area will be facilitated by the conservation of water, or reuse or the production of recycled water, under this permit. 8.7. Need to develop and use recycled water The State Water Board’s Recycled Water Policy requires the Central Coast Water Board to encourage the use of recycled water. In addition, as discussed immediately above, a need to develop and use recycled water exists within the region, especially during times of drought. To encourage recycling, the Permittee is required by this Order to continue to explore the feasibility of recycling to maximize the beneficial reuse of tertiary treated effluent and to report on its recycled water production and use. The Discharger shall submit an update to this feasibility investigation as part of the submittal of the Report of Waste Discharge (ROWD) for the next permit renewal. 9. PUBLIC PARTICIPATION The Central Coast Water Board is considering the issuance of WDRs that will serve as an NPDES permit for the City of San Luis Obispo Water Resource Recovery Facility. As a step in the WDR adoption process, Central Coast Water Board staff developed tentative WDRs and encourages public participation in the WDR adoption process. 9.1. Notification of Interested Persons The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provided an opportunity to submit written comments and recommendations. Notification was provided via the Central Coast Water Board’s website and e-mail subscription service. The public can access the agenda and any changes in dates and locations through the Central Coast Water Board’s website at http://www.waterboards.ca.gov/centralcoast/ 9.2. Written Comments Interested persons were invited to submit written comments on December 14, 2023, concerning these tentative WDRs. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-59 To be fully responded to by staff and considered by the Central Coast Water Board, the written comments were due at the Central Coast Water Board office by 5:00 p.m. on January 16, 2024. The Central Coast Water Board will hold a public hearing on the tentative WDRs during its regular Board meeting on the following date and time and at the following location: Date: April 18-19, 2024 Time: 9:00 am-5:00 pm Location: Link to video and teleconference were provided at https://www.waterboards.ca.gov/centralcoast/board_info/age ndas/2024/2024_agendas.html Interested persons are invited to attend. At the public hearing, the Central Coast Water Board will hear testimony pertinent to the discharge, WDRs, and permit. For accuracy of the record, important testimony was requested in writing. 9.4. Reconsideration of Waste Discharge Requirements Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Board must receive the petition by 5:00 p.m., within 30 calendar days of the date of adoption of this Order at the following address, except that if the thirtieth day following the date of this Order falls on a Saturday, Sunday, or state holiday, the petition must be received by the State Water Board by 5:00 p.m. on the next business day: State Water Resources Control Board Office of Chief Counsel P.O. Box 100, 1001 I Street Sacramento, CA 95812-0100 Or by email at waterqualitypetitions@waterboards.ca.gov For instructions on how to file a petition for review, see the State Water Board’s website on instructions for filing water quality petitions at: https://www.waterboards.ca.gov/public_notices/petitions/water_quality/wqpetition_i nstr.shtml. 9.5. Information and Copying The Report of Waste Discharge, other supporting documents, and comments received are on file and may be inspected at the address above at any time between 8:00 a.m. and 5:00 p.m., Monday through Friday. Copying of documents may be arranged through the Central Coast Water Board by calling (805) 549- 3147. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-60 9.6. Register of Interested Persons Any person interested in being placed on the mailing list for information regarding the WDRs and NPDES permit should contact the Central Coast Water Board, reference this facility, and provide a name, address, and phone number. 9.7. Additional Information Requests for additional information or questions regarding this order should be directed to Sarah Crable at (805) 549-3706 or Sarah.Crable@waterboards.ca.gov or Arwen Wyatt-Mair at (805) 542-4695 or Arwen.Wyattmair@waterboards.ca.gov. 113 From:McGrath, Patrick Sent:Friday, June 21, 2024 8:58 AM To:Anderson, Matt; Claxton, Christina Cc:Lehman, Chris Subject:FW: New NPDES Permit and TSO Adopted Attachments:draft_tso_slo_R3-2024-0021.docx; r3-2024-0001.pdf We’re still wildly overworked at the WRRF, and I’d prefer to not share this via email. @Claxton, Christina – can we plan on a debrief/presentation at our next monthly (July 3?) Thank you, Chris, for pushing back so hard on this. From: Lehman, Chris <clehman@slocity.org> Sent: Friday, June 21, 2024 8:33 AM To: McGrath, Patrick <pmcgrath@slocity.org>; Anderson, Matt <manderso@slocity.org>; Claxton, Christina <cclaxton@slocity.org> Cc: Floyd, Aaron <afloyd@slocity.org>; Barcenas, Miguel <MBarcena@slocity.org>; Boerman, Mychal <mboerman@slocity.org> Subject: New NPDES Permit and TSO Adopted Please share with your staff. The new SLO WRRF NPDES permit and TSO were adopted yesterday and will be effective on September 1, 2024. We will work with CASA, LWA, and a collective of agencies to take a coordinated approach to arguing against the new effluent salt limits as we carry out the mandatory deliverables identified in the TSO. The pond plants with WDRs are in an especially tough spot, including Atascadero, Santa Maria, Templeton, etc. Locally in SLO, we will advocate for a Basin Plan amendment and site-specific objectives. More to come on all of this in the coming months. Please ensure your staff have access to and begin to review the attached so we are prepared come September. Thanks, Chris Lehman Deputy Director - Wastewater Public Utilities 879 Morro st., San Luis Obispo, CA 93401-7314 E clehman@slocity.org T 805.781.7039 C 805.431.4372 slocity.org Stay connected with the City by signing up for e-notifications STATE OF CALIFORNIA CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401 DRAFT TIME SCHEDULE ORDER R3-2024-0021 REQUIRING THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY TO COMPLY WITH REQUIREMENTS PRESCRIBED IN NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT NO. CA0049224, ORDER R3-2024-0001 The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 1. The City of San Luis Obispo (Discharger) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (Facility), a publicly owned treatment works (POTW). The Facility is located at 35 Prado Road, San Luis Obispo, San Luis Obispo County. 2. Treatment at the Facility currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four Modified Ludzack-Ettinger (MLE) bioreactors, hollowfiber membranes, and ultraviolet (UV) disinfection. The biosolids handling unit consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. 3. On [placeholder for adoption date], the Central Coast Water Board adopted Waste Discharge Requirements Order R3-2024-0001, National Pollutant Discharge Elimination System (NPDES) Permit CA0049224. Order R3-2024-0001 regulates the discharge of tertiary treated effluent from the Facility to San Luis Obispo Creek, a water of the United States, located within the Estero Bay Hydrologic Unit. The effective date of Order R3-2024-0001 is [placeholder for effective date]. 4. Analysis of the Discharger’s effluent monitoring data from December 2014 through December 2022 found that the Discharger’s effluent had a reasonable potential to cause or contribute to exceedances of water quality objectives for total dissolved solids (TDS), chloride, sodium, sulfate, and molybdenum, and therefore warranted the establishment of effluent limitations for those parameters. 5. Order R3-2024-0001 prescribes the following new effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum. Table 1: Final effluent limitations in Order R3-2024-0001 Parameter Units Average Annual1 Average Monthly TDS mg/L 650 Chloride mg/L 100 DRAFT TSO R3-2024-0021 -2- September 1, 2024 1Compliance is determined using a 12-month running mean. NEED FOR TIME SCHEDULE ORDER AND REGULATORY REQUIREMENTS 6. The Discharger is unable to consistently comply with the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum, which were not effluent limits in the prior permit and are new to Order R3-2024-0001. In its January 11, 2024 comment letter on draft Order R3-2024-0001, the Discharger asked the Central Coast Water Board to include an in-permit compliance schedule to allow the Discharger time to develop and implement improvements to comply with the new effluent limits. 7. State Water Resources Control Board Resolution 2008-0025, Policy for Compliance Schedules in National Pollutant Discharge Elimination System Permits (Compliance Schedule Policy), was adopted on April 15, 2008. The Policy provides that in-permit compliance schedules should only be granted when additional time is needed to complete significant compliance actions to comply with new permit limitations implementing new, revised, or newly interpreted water quality objectives or criteria in water quality standards. The Compliance Schedule Policy defines the term “new, revised or newly interpreted water quality standard” to be standards adopted by the Central Coast Water Board after September 25, 1995. (Compliance Schedule Policy, p. 3, paragraph 1 subd. (d).) The Compliance Schedule Policy defines the term “newly interpreted water quality objective or criterion in a water quality standard,” as meaning: a narrative water quality objective or criterion that, when interpreted during NPDES permit development (using appropriate scientific information and consistent with state and federal law) to determine the permit limitations necessary to implement the objective, results in a numeric permit limitation more stringent than the limit in the prior NPDES permit issued to the discharger. Newly interpreted water quality objective or criterion in a water quality standard also includes a numeric or narrative water quality objective or criterion that is implemented with a permit limitation with which the discharger cannot comply because the pollutant was newly detected in the discharger’s effluent due to new analytical techniques that were developed after the prior permit was issued. (Id., p. 3, paragraph 1 subd. (e).) 8. The Water Quality Control Plan for the Central Coastal Basin (Basin Plan) includes numeric water quality objectives for TDS, chloride, sodium, sulfate, and molybdenum. Basin Plan Table 3-5 includes numeric mean surface water quality objectives for TDS, chloride, sodium, and sulfate specific to San Luis Obispo Creek. Table 3-2 includes the numeric water quality objective for molybdenum for waters with the agricultural supply beneficial use, which applies to San Luis Obispo Creek. These numeric water quality objectives were used in the analyses that found the Facility had reasonable potential to cause or contribute to exceedances of water quality objectives. These objectives have been part of the Basin Plan since at least 1994. Sodium mg/L 50 Sulfate mg/L 100 Molybdenum mg/L 0.01 DRAFT TSO R3-2024-0021 -3- September 1, 2024 9. The Discharger is not eligible for an in-permit compliance schedule because the water quality objectives used to establish the new effluent limitations for TDS, chloride, sodium, and sulfate in Order R3-2024-0001 were not new, revised, or newly interpreted water quality standards as that term is defined in the Compliance Schedule Policy. Similarly, the Discharger is not eligible for an in-permit compliance schedule for molybdenum because the water quality objective used to establish the new effluent limitation for molybdenum in Order R3-2024-0001 was not a new, revised, or newly interpreted water quality standard as that term is defined in the Compliance Schedule Policy. Although molybdenum is newly detected in the Discharger’s effluent through monitoring requirements established in the Discharger’s previous NPDES permit, Order R3-2014-0033, the analytical techniques were developed long before the prior permit was issued. 10. Considering the foregoing analysis, a time schedule order, issued pursuant to California Water Code (Water Code) sections 13300 and 13385(j)(3), is the appropriate mechanism to allow the Discharger additional time to comply with its effluent limitations in Order R3-2024-0001. 11. Section 13300 of the Water Code states: “Whenever a regional board finds that a discharge of waste is taking place or threatening to take place that violates or will violate requirements prescribed by the regional board, or the state board, or that the waste collection, treatment, or disposal facilities of a permittee are approaching capacity, the board may require the permittee to submit for approval of the board, with such modifications as it may deem necessary, a detailed time schedule of specific actions the permittee shall take in order to correct or prevent a violation of requirements.” 12. Water Code section 13385, subdivisions (h) and (i), require the Central Coast Water Board to impose mandatory minimum penalties upon dischargers that violate certain effluent limitations. Section 13385(j)(3)(A) exempts violations of an effluent limitation from mandatory minimum penalties "where the waste discharge is in compliance with … a time schedule order issued pursuant to Section 13300, if all of the [specified] requirements are met." (emphasis added). 13. Pursuant to Water Code section 13385 subdivision (j)(3)(B)(i), the Central Coast Water Board finds that, based on effluent monitoring data, the Discharger is not able to consistently comply with the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum in Order R3-2024-0001 while new or modified control measures are implemented to increase pollutant removal efficiency or reduce the amount of these pollutants the facility receives. The effluent limitations for these pollutants are new requirements for the Discharger, and a time schedule order will allow the Discharger time to assess discharges to the collection system, collect data, perform studies, and develop additional pretreatment and control options for molybdenum and high-concentration TDS, chloride, sodium, and sulfate dischargers within the city. In addition, the new or modified control measures cannot be designed, installed, and put into operation within 30 calendar days. 14. The Discharger intends to carry out source control measures by implementing a pollution prevention plan, performing a source identification study, and performing a pretreatment program local limits study. During these efforts, the Discharger may be temporarily unable to comply with the Order R3-2024-0001 final effluent limitations DRAFT TSO R3-2024-0021 -4- September 1, 2024 for TDS, chloride, sodium, sulfate, and molybdenum, and interim effluent limits are necessary. The period of this time schedule order is September 1, 2024, through August 31, 2029. 15. During the period of the time schedule order, the Discharger will continue to operate and discharge under all the limitations specified in Order R3-2024-0001 except for TDS, chloride, sodium, sulfate, and molybdenum. The Discharger will continue to report on all parameters as specified in Order R3-2024-0001. 16. Pursuant to Water Code section 13223, the Central Coast Water Board has delegated to its Executive Officer the authority to issue a time schedule order pursuant to Water Code section 13300. 17. Water Code section 13383 authorizes the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements for any person who owns or operates a publicly owned treatment works. In accordance with 40 C.F.R. sections 25.5 and 124.10 subd. (b)(1) and Water Code section 13378, the Central Coast Water Board publicly noticed this time schedule order from March 12, 2024 through April 11, 2024. No public comments were received. 18. Issuance of this time schedule order is exempt from provisions of the California Environmental Quality Act (Pub. Resources Code, section 21000 et seq.) (CEQA) pursuant to Water Code section 13389 because the adoption or modification of an NPDES permit for an existing source is statutorily exempt from CEQA, and this time schedule order only serves to implement an NPDES permit. (Pacific Water Conditioning Ass’n, Inc. v. City Council of City of Riverside (1977) 73 Cal. App. 3d 546, 555-556). Furthermore, this enforcement action is taken for the protection of the environment and as such is exempt from CEQA in accordance with section 15321, chapter 3, title 14, California Code of Regulations. MANDATORY MINIMUM PENALTIES 19. Pursuant to Water Code section 13385(j)(3), violations of the final effluent limits for TDS, chloride, sodium, sulfate, and molybdenum in Order R3-2024-0001 are not subject to Water Code section 13385 subdivisions (h) and (i) mandatory minimum penalties, provided the Discharger complies with all the requirements of this time schedule order and all the following conditions are met: a. The time schedule order specifies the actions that the Discharger is required to take in order to correct the violations that would otherwise be subject to subdivisions (h) and (i). b. The Central Coast Water Board finds that the Discharger is not able to consistently comply with one or more of the effluent limitations established in the waste discharge requirements applicable to the waste discharge for one of the reasons described in Water Code section 13385(j)(3)(B)(i)-(iv) (see Paragraph 12, supra). c. The Central Coast Water Board establishes a time schedule for bringing the waste discharge into compliance with the final effluent limitation that is as short as possible and does not exceed five years in length. d. For time schedules that exceed one year from the effective date of the time schedule order, the schedule shall include interim requirements and the dates for their achievement. The interim requirements shall include both of the following: DRAFT TSO R3-2024-0021 -5- September 1, 2024 i. Effluent limitations for the pollutant or pollutants of concern. ii. Actions and milestones leading to compliance with the effluent limitation. e. The Discharger has prepared and is implementing in a timely and proper manner or is required by the Central Coast Water Board to prepare and implement a pollution prevention plan pursuant to CWC section 13263.3. This time schedule order requires the Discharger to prepare, implement, and submit a pollution prevention plan for TDS, chloride, sodium, sulfate, and molybdenum. This time schedule order satisfies the above conditions a-e. 20. This time schedule order requires the Discharger to comply with a time schedule by August 31, 2029, that will allow the Discharger to achieve full compliance with TDS, chloride, sodium, sulfate, and molybdenum final effluent limitations in Order R3-2024- 0001. 21. This time schedule order includes performance-based interim effluent limitations that are based on the 97.22 percentile for results measured from 2015 to 2023 for TDS, chloride, sodium sulfate, and molybdenum as shown in Table 3. 22. The Central Coast Water Board expects that the Discharger can maintain compliance with the interim effluent limitations included in this time schedule order. Interim effluent limitations are established when compliance with the final effluent limitations cannot be achieved by the existing Facility. Discharge of pollutants in concentrations in excess of the final limitations in the permit, but in compliance with the interim effluent limitations, can significantly degrade water quality and adversely affect the beneficial uses of the receiving stream on a long-term basis. The interim effluent limitations, however, establish an enforceable ceiling value until compliance with the final effluent limitations can be achieved. 23. If an interim effluent limit established in this time schedule order for TDS, chloride, sodium, sulfate, or molybdenum is exceeded, then the Discharger is subject to a mandatory minimum penalty for that particular exceedance as the Discharger will no longer meet the exemption in Water Code section 13385, subdivision (j)(3). IT IS HEREBY ORDERED, pursuant to California Water Code sections 13300 and 13383 and to ensure compliance with the requirements of adopted Waste Discharge Requirements Order R3-2024-0001, NPDES Permit CA0049224: 1. The Discharger shall comply with the following schedule of actions: DRAFT TSO R3-2024-0021 -6- September 1, 2024 Table 2. Compliance Schedule for Total Dissolved Solids, Chloride, Sodium, Sulfate, Molybdenum (Starting September 1, 2024) Required Actions Compliance Due Dates Submit semi-annual progress and sampling results of TDS, chloride, sodium, sulfate, and molybdenum in Facility influent and effluent. Reports shall include but not be limited to: • Discussion of overall progress in implementing the requirements of this TSO and achieving full compliance with Order R3-2024-0001 • Results of source identification efforts and potential modifications to local limits or other pretreatment program actions • Evaluation of compliance with final effluent limitations • Update the Pollution Prevention Plan (PPP) section with descriptions of actions to be taken in the upcoming year beginning with the August 15, 2025 report and annually thereafter. 1st Semi-annual Report (Jan-Jun) – due by Feb 15 2nd Semi-annual Report (Jul-Dec) – due by Aug 15 Submit Pollution Prevention Plan (PPP) for TDS, chloride, sodium, sulfate, and molybdenum. Requirements for the PPP are set forth below. Submit an annual update to the PPP as a section in the semi-annual progress report describing planned actions for the upcoming year and discussing results from the previous year. PPP for calendar year 2025 due January 15, 2025 Updated PPP for 2026 due Aug 15, 2025 Updated PPP for 2027 due Aug 15, 2026 Updated PPP for 2028 due Aug 15, 2027 Updated PPP for 2029 due Aug 15, 2028 Submit Source Identification Study plan for review and approval by the Executive Officer. Requirements for the Source Identification Study are set forth below. January 15, 2025 Initiate Source Identification Study May 31, 2025 Submit Local Limits Study plan for review and approval by the Executive Officer. Requirements for the Local Limits Study are set forth below. May 1, 2026 Submit Source Identification Study results. Nov 1, 2026 Initiate Local Limits Study. Nov 1, 2026 DRAFT TSO R3-2024-0021 -7- September 1, 2024 Required Actions Compliance Due Dates Submit draft Local Limits Study report, including proposed changes to local limits. Nov 1, 2027 Submit final Local Limits Study report. May 1, 2028 Achieve full compliance with final effluent limitations in Order R3-2024-0001. August 31, 2029 Pollution Prevention Plan (PPP): The PPP is an iterative plan that the Discharger will update and submit on an annual basis. The annual PPP must include the following deliverables: a. A description of new or modified methods that will be used to prevent or reduce the amount of TDS, chloride, sodium, sulfate, and molybdenum in the facility's influent and effluent during the upcoming year. Pollution prevention methods may include application and enforcement of local limits to industrial or commercial dischargers, public education and outreach, upgrades or changes to the Facility’s treatment system, or other innovative and alternative approaches to reduce discharges of TDS, chloride, sodium, sulfate, and molybdenum to and from the facility. b. An estimate of load reductions that may be attained through the methods identified above. c. A plan for monitoring and assessing the results of the pollution prevention plan. d. A discussion of the pollution prevention methods used during the previous year. e. An estimate of the load reductions that were attained during the previous year. f. Once completed, a summary of the findings of the Source Identification Study, including the monitoring results and all identified sources of TDS, chloride, sodium, sulfate, and molybdenum to and from the Facility. g. Once completed, a discussion of the findings of the Local Limits Study and a description of how the Facility’s pretreatment program will be modified. Source Identification Study: The Source Identification Study must, at a minimum, include a sampling plan consistent with the guidance in Chapter 4 of EPA’s Local Limits Development Guidance.1 The sampling must occur for a minimum of one year and must be carried out in such a manner that it is spatially and temporally representative. The Source Identification Study may include additional source identification or monitoring that the Discharger identifies as being useful in understanding and reducing all sources of pollutants in the Facility’s influent and effluent. Local Limits Study: The Local Limits Study must include a detailed re-evaluation of local limits, as described in EPA’s Local Limits Development Guidance. The Local Limits Study will use the results of the Source Identification Study to calculate or recalculate maximum allowable headworks loadings (MAHLs) for TDS, chloride, 1 https://www3.epa.gov/npdes/pubs/final_local_limits_guidance.pdf DRAFT TSO R3-2024-0021 -8- September 1, 2024 sodium, sulfate, molybdenum, and any other pollutants identified as requiring further evaluation. The Discharger must use the MAHLs to develop or update local limits. 2. If the Discharger is unable to perform any activity or submit any documentation in compliance with the deadlines set forth in Table 2, the Discharger may request, in writing, an extension of the time. The extension request shall include justification for the delay and shall be submitted at least thirty days prior to the respective deadline to be considered complete and timely. 3. The following interim effluent limitations for TDS, chloride, sodium, sulfate, and molybdenum shall be effective upon issuance of this time schedule order and shall apply in lieu of all final effluent limitations for those pollutants in Order R3-2024-0001. The Discharger shall maintain compliance with the following interim effluent limitations through August 31, 2029, or until the Discharger is able to come into compliance with the final effluent limitations, whichever is sooner. Table 3: Interim effluent limitations 1Compliance is determined using a 12-month running mean. 4. All reports shall be submitted under Discharger signed/certified cover letter to the California Integrated Water Quality System (CIWQS). The Executive Officer may require revisions to the form or types of data and information reported. 5. All reports required by this time schedule order shall be signed by either a principal executive officer or ranking elected official, or by a duly authorized representative of that person. A person is a duly authorized representative only if: a. The authorization is made in writing by a person described above; b. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the owner of the regulated facility. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.); and c. The written authorization is submitted to the Central Coast Water Board. 6. Any person signing a report required by this time schedule order shall make the following certification: “I certify under penalty of perjury that this document and all attachments were prepared by me, or under my direction or supervision, following a system designed to ensure that qualified personnel properly gather and evaluate the information submitted. To the best of my knowledge and belief, this document and all attachments are true, accurate, and complete. I am aware that there are significant Parameter Units Average Annual1 Average Monthly TDS mg/L 988 Chloride mg/L 196 Sodium mg/L 196 Sulfate mg/L 157 Molybdenum mg/L 0.024 DRAFT TSO R3-2024-0021 -9- September 1, 2024 penalties for submitting false information, including the possibility of fine and imprisonment.” 7. If, in the opinion of the Executive Officer, the Discharger fails to comply with any provisions of this time schedule order or fails to consistently demonstrate substantive progress towards achieving full compliance with effluent limitations in Order R3-2024- 0001, the Executive Officer may terminate this time schedule order. In that case, or if compliance with the final effluent limitations for TDS, chloride, sodium, sulfate, or molybdenum in Order R3-2024-0001 is not achieved by the full compliance dates shown above in Table 2 or the Discharger has not received an extension according to Provision 2 above, the Discharger will not be exempt from the mandatory minimum penalties for violation of those effluent limitations and may also be subject to issuance of a cease and desist order in accordance with Water Code section 13301. The Central Coast Water Board reserves its right to take any enforcement action authorized by law. 8. During the effective period of this time schedule order, the Discharger shall comply with all provisions of Order R3-2024-0001, as renewed or revised, that are not in conflict with this time schedule order. If, in the opinion of the Executive Officer, the Discharger fails to comply with the provisions of this order, the Executive Officer may refer this matter to the Attorney General for judicial enforcement, may issue a complaint for administrative civil liability, or may take other enforcement actions. Failure to comply with this order may result in the assessment of administrative civil liability of up to $10,000 per violation, per day, depending on the violation, pursuant to the Water Code, including sections 13350 and 13385. The Central Coast Water Board reserves its right to take any enforcement actions authorized by law. Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Resources Control Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Resources Control Board must receive the petition by 5:00 p.m., 30 days after the date of the order, except that if the thirtieth day following the date of the order falls on a Saturday, Sunday, or state holiday, the petition must be received by 5:00 p.m. on the next business day. Copies of the law and regulations applicable to filing petitions may be found on the internet at: http://www.waterboards.ca.gov/public_notices/petitions/water_quality, or will be provided upon request. This Order is effective on [placeholder for TSO effective date]. The Executive Officer may modify the time schedule in this order to permit a specified task or tasks to be completed at later dates if the Discharger demonstrates and the Executive Officer determines that the delay was beyond the reasonable control of the Discharger to avoid. ORDERED BY ___ Ryan E. Lodge, Executive Officer DRAFT TSO R3-2024-0021 -10- September 1, 2024 R:\RB3\Shared\NPDES\Facilities\San Luis Obispo\San Luis Obispo\TSO R3-2024- 0021\Draft TSO\draft_tso_slo_R3-2024-0021.docx Place ID: 255380 CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD CENTRAL COAST REGION 895 Aerovista Place, Suite 101, San Luis Obispo, California 93401 Phone (805) 549-3147 Fax (805) 543-0397 Central Coast Regional Water Quality Control Board (http://www.waterboards.ca.gov/centralcoast) DRAFT ORDER R3-2024-0001 NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM PERMIT NUMBER CA0049224 WASTE DISCHARGE REQUIREMENTS FOR THE CITY OF SAN LUIS OBISPO WATER RESOURCE RECOVERY FACILITY The following Discharger is subject to waste discharge requirements set forth in this Order: Discharger City of San Luis Obispo Name of Facility Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Table 1. Discharge Location Discharge Point Effluent Description Discharge Point Latitude (North) Discharge Point Longitude (West) Receiving Water 001 Tertiary treated domestic wastewater 35.244307° -120.680618° San Luis Obispo Creek 002 Disinfected Tertiary Recycled Municipal Wastewater - - Reclamation Use This Order was adopted on: April 18-19, 2024 This Order shall become effective on: July 1, 2024 This Order shall expire on: June 30, 2029 The Discharger shall file a Report of Waste Discharge as an application for reissuance of waste discharge requirements in accordance with title 23, California Code of Regulations and an application for reissuance of a National Pollutant Discharge CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 2 Elimination System permit no later than 180 days prior to the Order expiration date. The U.S. Environmental Protection Agency and the California Regional Water Quality Control Board, Central Coast Region have classified this discharge as follows: Major discharge. I, Ryan E. Lodge, Executive Officer, do hereby certify that this Order with all attachments is a full, true, and correct copy of an order adopted by the California Regional Water Quality Control Board, Central Coast Region on the date indicated above. Ryan E. Lodge, Executive Officer CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 3 TABLE OF CONTENTS 1. FACILITY INFORMATION .......................................................................................... 4 2. FINDINGS ................................................................................................................... 4 3. DISCHARGE PROHIBITIONS .................................................................................... 7 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS ................................. 7 4.1. Effluent Limitations – Discharge Point 001 ........................................................ 7 4.2. Land Discharge Specifications – Not Applicable ............................................. 11 4.3. Recycling Specifications – Discharge Point 002 ............................................. 11 5. RECEIVING WATER LIMITATIONS ......................................................................... 12 5.1. Surface Water Limitations ............................................................................... 12 5.2. Groundwater Limitations ................................................................................. 16 6. PROVISIONS ............................................................................................................ 17 6.1. Standard Provisions ........................................................................................ 17 6.2. Monitoring and Reporting Program (MRP) Requirements ............................... 17 6.3. Special Provisions ........................................................................................... 17 7. COMPLIANCE DETERMINATION ............................................................................ 23 TABLE OF TABLES Table 1. Discharge Location ............................................................................................ 1 Table 2. Effluent Limitations at Discharge Point 001 ....................................................... 7 Table 3. Organic Substances Water Quality Criteria ..................................................... 14 Table 4. Hardness Dependent Metals Criteria .............................................................. 15 Table 5. Annual Mean Surface Water Quality Objectives .............................................. 15 Table 6. Groundwater Objectives .................................................................................. 17 TABLE OF ATTACHMENTS ATTACHMENT A – DEFINITIONS ...............................................................................A-1 ATTACHMENT B – MAP ..............................................................................................B-1 ATTACHMENT C – FLOW SCHEMATIC .................................................................... C-1 ATTACHMENT D – STANDARD PROVISIONS ......................................................... D-1 ATTACHMENT E – MONITORING AND REPORTING PROGRAM ............................E-1 ATTACHMENT F – FACT SHEET ............................................................................... F-1 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 4 1. FACILITY INFORMATION Information describing the City of San Luis Obispo (Discharger) Water Resource Recovery Facility (Facility) is summarized on the cover page and in sections 1 and 2 of the Fact Sheet (Attachment F). Section 1 of the Fact Sheet also includes information regarding the Facility’s permit application. 2. FINDINGS The California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) finds: 2.1. Legal Authorities. This Order serves as waste discharge requirements (WDRs) pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA) and implementing regulations adopted by the United States Environmental Protection Agency (U.S. EPA) and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as a National Pollutant Discharge Elimination System (NPDES) permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1 subject to the WDRs in this Order. 2.2. Background and Rationale for Requirements. The Central Coast Water Board developed the requirements in this Order based on information submitted as part of the application, through monitoring and reporting programs, and other available information. The Fact Sheet (Attachment F), which contains background information and rationale for the requirements in this Order, is hereby incorporated into and constitutes Findings for this Order. Attachments A through E are also incorporated into this Order. 2.3. Provisions and Requirements Implementing State Law. Some provisions/requirements in this Order are included to implement state law only. These provisions/requirements are not required or authorized under the federal CWA; consequently, violations of these provisions/requirements are not subject to the enforcement remedies that are available for NPDES violations. 2.4. Water Reclamation Requirements for Recycled Water Production and Use. This Order allows the production and use of disinfected secondary and tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements established by the California Department of Public Health in title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. Additionally, this Order includes water reclamation requirements for the Facility pursuant to the State Water Resources Control Board’s (State Water Board’s) Division of Drinking Water (DDW) recommendations submitted to the Central Coast Water Board. The distribution and offsite reuse of recycled water produced by the Facility is subject to the State Water Board’s General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW), or other applicable permit, dependent on final use. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 5 2.5. Response to Climate Change. Climate change refers to observed changes in regional weather patterns such as temperature, precipitation, and storm frequency and size. At the local scale, within urbanized areas, climate change may directly impact groundwater and surface water supply; drainage, flooding, and erosion patterns; and ecosystems and habitat. This shift in climate, combined with California’s growing population, has increased reliance on pumping, conveying, treating, and heating water, increasing the water sector’s greenhouse gas emissions. The State Water Board’s Resolution 2017-0012, Comprehensive Response to Climate Change, requires a proactive response to climate change in all California Water Board actions, with the intent to embed climate change consideration into all programs and activities. Aligning with Resolution 2017-0012, this Order supports the beneficial reuse of the Facility’s treated effluent to offset potable water supplies for irrigation and dedicated in-stream flows to support critical creek habitat. This Order incorporates requirements for the Facility to beneficially reuse treated effluent, which serves to diversify the State’s water supply portfolio to prepare for uncertainties in water resources due to the changing climate through ongoing implementation, monitoring, and updating of the Discharger’s climate action planning efforts using the best available data and technology for wastewater treatment and operation. In 2019, the City participated in the development of the Multi-Jurisdictional San Luis Obispo Hazard Mitigation, a planning effort that identifies and prioritizes the City’s vulnerability to hazards and outlines mitigation goals and objectives. In August 2020, the City adopted its Climate Action Plan with goals for community-wide carbon neutrality by 2035. Most recently, on January 17, 2023, The City adopted the Climate Adaptation and Safety Element as part of its general plan. According to Disaster Mitigation Act (DMA) requirement §201.6(d)(3), the City must review and revise this plan within five years for continued mitigation project grant funding. Additionally, the City is currently undergoing construction of the SLO Water Plus project, which includes Facility upgrades to improve the Facility’s energy efficiency, provide flood protection improvements, increase treatment capacity, and improve resource recovery. To incorporate proactive planning for the future, this Order requires the Discharger to report on implementation progress, monitoring, and planning updates at this Facility as it relates to flooding, wildfire, renewable energy generation and energy efficiency, temperature, water recycling, biosolids reuse, and influent flow and loading fluctuations exacerbated by climate change. 2.6. Human Right to Water. California Water Code section 106.3 established the policy that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. On January 26, 2017, the Central Coast Water Board adopted Resolution R3-2017- 0004, which adopts the human right to water as a core value and affirms the realization of the human right to water and protecting human health as the Central Coast Water Board's top priorities. Consistent with the human right to water stated in California Water Code section 106.3, subdivision (a), and the Central Coast Water Board’s Resolution R3-2017-0004, this Order promotes actions that advance the human right to water and discourages actions that delay or impede opportunities for communities to secure safe, clean, affordable, and accessible CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 6 water adequate for human consumption, cooking, and sanitary purposes. This Order implements recently updated mercury water quality objectives that are more stringent than previous objectives to more adequately protect beneficial uses related to water and fish consumption. 2.7. Disadvantaged Community Status. Environmental Justice principles call for the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income in the development, adoption, implementation, and enforcement of all environmental laws, regulations, and policies that affect every community’s natural resources and the places people live, work, play, and learn. The Central Coast Water Board implements regulatory activities and water quality projects in a manner that ensures the fair treatment of all people, including Underrepresented Communities. Underrepresented Communities include but are not limited to Disadvantaged Communities (DACs), Severely Disadvantaged Communities (SDACs), Economically Distressed Areas (EDAs), Tribes, Environmentally Disadvantaged Communities (EnvDACs), and members of Fringe Communities.1 Furthermore, the Central Coast Water Board is committed to providing all stakeholders the opportunity to participate in the public process and provide meaningful input to decisions that affect communities. To meet environmental justice principles, staff has evaluated the disadvantaged community status for the Discharger. Using 2020 census data, the California Department of Water Resources Disadvantaged Community (DAC) Mapping Tool 1 identifies 16 block groups in the City of San Luis Obispo, representing approximately 54 percent of the population, as disadvantaged communities. The tool defines a DAC as a census block with a median household income between $50,458 and $67,278 and a severely disadvantaged community (SDAC) as a census block with a median household income below $50,458. The SDAC census blocks in the City of San Luis Obispo have median household incomes of $8,075, $9,596, $11,935, $28,173, $28,284, $35,774, $39,526, and $44,167. The DAC census blocks in the City of San Luis Obispo have median household income of $51,074, $52,961, $55,769, $56,866, $57,175, $57,803, $58,083, and $60,417. 2.8. Notification of Interested Persons. The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provided them with an opportunity to submit their written comments and recommendations. Details of the notification are provided in the Fact Sheet, Attachment F. 2.9. Consideration of Public Comment. The Central Coast Water Board, in a public meeting, heard and considered all comments pertaining to the discharge. Details of the public hearing are provided in the Fact Sheet, Attachment F. THEREFORE, IT IS HEREBY ORDERED that this Order supersedes Order R3-2014- 0033, except for enforcement purposes, that Waste Discharge/Master Reclamation 1 The DAC Mapping Tool is used to inform statewide Integrated Water Resources Management (IRWM), Sustainable Groundwater Monitoring Act (SGMA), and California Water Plan implementation efforts and can be found at the following website: https://gis.water.ca.gov/app/dacs/. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 7 Requirements Order R3-2003-081 is terminated upon Discharger’s enrollment in State Water Board Order WQ-2016-0068-DDW, except for enforcement purposes, and, in order to meet the provisions contained in division 7 of the California Water Code (commencing with section 13000) and regulations adopted thereunder and the provisions of the CWA and regulations and guidelines adopted thereunder, the Discharger shall comply with the requirements in this Order. This action in no way prevents the Central Coast Water Board from taking enforcement action for violations of the previous orders. 3. DISCHARGE PROHIBITIONS 3.1. Discharge of treated wastewater at a location or in a manner other than as described by this Order at Discharge Points 001 and 002, with compliance measured at EFF-001 and EFF-002 respectively as described in the Monitoring and Reporting Program (MRP) Attachment E, is prohibited. 3.2. The discharge of any waste not specifically regulated by this Order, excluding stormwater regulated by General Permit CAS000001 (Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities), is prohibited. 3.3. The overflow or bypass of wastewater from the Discharger’s collection, treatment, or disposal facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7 (Bypass), is prohibited. 3.4. Creation of a condition of pollution, contamination, or nuisance, as defined by section 13050 of the California Water Code, is prohibited. 3.5. The discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat. 3.6. The discharge of radioactive substances is prohibited. 3.7. The average dry weather daily discharge flow shall not exceed 5.4 million gallons per day (MGD). 4. EFFLUENT LIMITATIONS AND DISCHARGE PROHIBITIONS 4.1. Effluent Limitations – Discharge Point 001 4.1.1. Final Effluent Limitations – Discharge Point 001 4.1.1.1. The Discharger shall maintain compliance with the following effluent limitations at Discharge Point 001, with compliance measured at Monitoring Location EFF- 001A or EFF-001B as described in the Monitoring and Reporting Program (MRP), Attachment E. Table 2. Effluent Limitations at Discharge Point 001 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 8 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1,351 2,252 - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - TSS lbs/day[1] 425 1,351 3,378 - - - pH[2],[3] standard units - - - 7.0 8.3 - Oil and Grease mg/L 5 - 10 - - - Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - Dissolved Oxygen mg/L - - - 4.0 - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.012 - 0.024 - - - Chlorodibromomethane (Dibromochloromethane) µg/L 0.40 - 0.81 - - - Chloroform µg/L 60 - 120.6 - - - Dichlorobromomethane µg/L 0.56 - 0.96 - - - CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 9 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Methylene Chloride µg/L 4.7 - 9.45 - - - Pentachlorophenol µg/L 0.28 - 0.56 - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - Nitrite, Total mg/L 1 - - - - - Un-ionized Ammonia mg/L 0.025 - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - Molybdenum mg/L 0.01 - - - - - Total Dissolved Solids mg/L 650 - - - - - Chloride mg/L 100 - - - - - Sodium mg/L 50 - - - - - Sulfate mg/L 100 -- - - - - Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail ” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 10 [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 7.0-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 7.0-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0-9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 7.0-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30- day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in-stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP-Attachment E). 4.1.1.2. Percent Removal: The average monthly percent removal of BOD 5-day at 20°C and total suspended solids shall not be less than 85 percent. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 11 4.1.1.3. Floating Material: Discharge of treated wastewater through Discharge Point 001 shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 4.1.2. Interim Effluent Limitations – Not Applicable 4.2. Land Discharge Specifications – Not Applicable 4.3. Recycling Specifications – Discharge Point 002 As specified below, this Order conditionally authorizes the Discharger to act as the producer of recycled (or reclaimed) water and to reuse recycled water onsite at the Facility and for other purposes. The Discharger is responsible for compliance with all applicable requirements associated with the production and onsite use of recycled water as specified within this Order. The Discharger filed a California Code of Regulations title 22 engineering report on August 14, 2020, that described recycled water quality produced at the Facility as "disinfected tertiary" (as defined in title 22, section 60301.230) and submitted a Notice of Intent (NOI) on August 14, 2020, to enroll under the State Water Board General Water Reclamation Requirements for Recycled Water Use (Order WQ 2016-0068-DDW). The distribution and offsite reuse of recycled water produced by the Facility are subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. Order WQ 2016-0068-DDW supersedes Waste Discharge/Master Reclamation Requirements Order R3-2003-081. 4.3.1. Reclamation and use of treated wastewater shall adhere to applicable requirements of California Water Code sections 13500-13577 (Water Reclamation) and California Code of Regulations, title 17 sections 7583-7586, title 17 sections 7601-7605, and title 22 sections 60301-60355 (Uniform Statewide Recycling Criteria). 4.3.2. Recycled water production shall comply with a title 22 engineering report approved by DDW that demonstrates or defines compliance with the Uniform Statewide Recycling Criteria. 4.3.3. Recycled water shall be disinfected tertiary recycled water, as defined by California Code of Regulations title 22, section 60301.230. 4.3.4. Recycled water shall be adequately oxidized, filtered, and disinfected, as defined in title 22. 4.3.5. Turbidity in tertiary recycled water shall not exceed any of the following limits: 4.3.5.1. An average of 0.2 NTU within a 24-hour period; and 4.3.5.2. 0.5 NTU at any time. 4.3.6. Total coliform bacteria measured in the disinfected recycled water shall not exceed the following limits: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 12 4.3.6.1. An MPN of 2.2 per 100 mL calculated as a median concentration utilizing the bacteriological results of the last seven days for which analyses have been completed, 4.3.6.2. An MPN of 23 per 100 mL in more than one sample in any 30-day period, and 4.3.6.3. No sample shall exceed an MPN of 240 total coliform bacteria per 100 mL. 4.3.7. The Discharger shall discontinue delivery of recycled water to distributors and users during any period in which it has reason to believe that the limits established in this Order are not being met. The delivery of recycled water shall not be resumed until all conditions that caused the limits to be violated have been corrected. 4.3.8. Recycled water shall not exceed any maximum contaminant level established pursuant to sections 116275(c)(1) and (d) of the California Health and Safety Code or established by the U.S. EPA. 4.3.9. Recycled water disinfected with chlorine shall have a chlorine concentration time modal contact time (CT) value of not less than 450 mg-min/L at all times with a modal contact time of at least 90 minutes based on peak dry weather design flow. 4.3.10 If a disinfection method other than chlorine is used, the disinfection process shall be a process that, when combined with the filtration process, has been demonstrated to inactivate and/or remove 99.999 percent of the plaque forming units of F-specific bacteriophage MS2, or polio virus in the wastewater. A virus that is at least as resistant to disinfection as polio virus may be used for purposes of the demonstration. 4.3.11. The Discharger shall adhere to the manufacturer’s recommended operating conditions for the ultraviolet (UV) system. 4.3.12. Personnel involved in producing, transporting, or using recycled water shall be informed of possible health hazards that may result from contact and use of recycled water. 4.3.13. All areas where recycled water is in use and with public access shall be posted with signs in English and an international symbol to warn the public that recycled wastewater is being stored or used. 4.3.14. Recycled water systems at the Facility shall be properly labeled and regularly inspected to ensure proper operation, absence of leaks, and absence of illegal connections. 5. RECEIVING WATER LIMITATIONS 5.1. Surface Water Limitations Receiving water limitations are based on water quality objectives contained in the Water Quality Control Plan for the Central Coastal Basin (Basin Plan) and are a required part of this Order. The discharge shall not cause a violation of the following receiving water limitations in San Luis Obispo Creek. The discharge from the wastewater treatment facility shall comply with the following in the receiving waters: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 13 5.1.1. Waters shall be free of coloration that causes nuisance or adversely affects beneficial uses. Coloration attributable to materials of waste origin shall not be greater than 15 units or 10 percent above natural background color, whichever is greater. 5.1.2. Waters shall not contain taste or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, that cause nuisance, or that adversely affect beneficial uses. 5.1.3. Waters shall not contain floating material, including solids, liquids, foams, and scum, in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.4. Waters shall not contain suspended material in concentrations that cause nuisance or adversely affect beneficial uses. 5.1.5. Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. 5.1.6. Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. 5.1.7. Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses. 5.1.8. The suspended sediment load and suspended sediment discharge rate to surface waters shall not be altered in such a manner as to cause nuisance or adversely affect beneficial uses. 5.1.9 Concentrations of toxic metals and inorganic chemicals in waters shall not be increased in such a manner that may adversely affect beneficial uses. 5.1.10. Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Increase in turbidity attributable to controllable water quality factors shall not exceed the following limits. 5.1.10.1. Where natural turbidity is between 0 and 50 NTUs, increases shall not exceed 20 percent. 5.1.10.2. Where natural turbidity is between 50 and 100 NTUs, increases shall not exceed 10 NTU. 5.1.10.3. Where natural turbidity is greater than 100 NTUs, increases shall not exceed 10 percent. 5.1.11. The pH value shall not be depressed below 7.0 nor raised above 8.3. The change in normal ambient pH levels shall not exceed 0.5 units. 5.1.12. Dissolved oxygen concentrations in receiving waters shall not be reduced below 7.0 mg/L at any time. 5.1.13. Discharged effluent shall not cause the receiving water temperature to increase more than 5° Fahrenheit (F) above the receiving water temperature. If, due to CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 14 the Creek’s low temperature as determined by early-morning monitoring, the discharge causes the Creek’s temperature to exceed the limit, the Discharger must ensure the discharge shall not cause the receiving water to exceed 72.5° F (22.5° C). The discharger shall monitor the Creek again four hours after discovering the exceedance and shall report both results to the Executive Officer in the monthly self-monitoring report. 5.1.14. All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant, animal, or aquatic life. Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge. 5.1.15. The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/L (as N) in the receiving water. 5.1.16. No individual pesticide or combination of pesticides shall reach concentrations that adversely affect the beneficial uses of the receiving water. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life. For waters where existing concentrations are presently nondetectable or where beneficial uses would be impaired by concentrations in excess of nondetectable levels, total identifiable chlorinated hydrocarbon pesticides shall not be present at concentrations detectable within the accuracy of analytical methods as prescribed in Standard Methods for the Examination of Water and Wastewater, latest edition, or other equivalent methods approved by the Executive Officer. 5.1.17. Waters shall not contain organic substances in concentrations greater than those listed in the table below: Table 3. Organic Substances Water Quality Criteria Parameter Units Water Quality Objective Methylene Blue Activated Substances mg/L 0.2 Phenols ug/L 1.0 Polychlorinated Biphenyls (PCBs) [1] µg/L 0.3 Phthalate Esters µg/L 0.002 [1] PCBs refer to sum of PCB 1016, 1221, 1232, 1242, 1248, 1254, and 1260. 5.1.18. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstance shall receiving waters contain concentrations of radionuclides in excess of the maximum contaminant levels (MCLs) for radioactivity presented in title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.1.19. Receiving waters shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 15 Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.1.20. Receiving waters shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural beneficial use. Interpretation of adverse effects shall be derived from the University of California Agricultural Extension Service guidelines presented in section 3, Table 3-1 of the 2019 Basin Plan. 5.1.21. Receiving waters shall not contain concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in section 3, Table 3-2 of the Basin Plan. Salt concentrations for irrigations waters shall be controlled through implementation of the anti-degradation policy to the effect that mineral constituents of currently or potentially usable waters shall not be increased. 5.1.22. Receiving waters shall not contain concentrations of chemical constituents known to be deleterious to fish or wildlife in excess of the levels presented in section 3, Table 3-3 of the 2019 Basin Plan. The concentrations of metals listed in the table below shall not be exceeded for the protection of aquatic life. Table 4. Hardness Dependent Metals Criteria Parameter Units Receiving Water Hardness >100 mg/L calcium carbonate (CaCO3) Receiving Water Hardness <100 mg/L CaCO3 Cadmium mg/L 0.003 0.0004 Chromium mg/L 0.05 0.05 Copper mg/L 0.03 0.01 Lead mg/L 0.03 0.03 Mercury mg/L 0.0002 0.0002 Nickel mg/L 0.4 0.1 Zinc mg/L 0.2 0.004 5.1.23. E. coli concentrations shall not exceed 100 MPN/100 mL as a 6-week rolling geometric mean, calculated weekly. A statistical threshold value (STV) of 320 MPN/100 mL for E. coli shall not be exceeded by more than 10 percent of samples collected in a calendar month, calculated in a static manner. 5.1.24. Discharges shall not cause receiving water to exceed the water quality objectives for the Estero Bay Hydrologic Unit (San Luis Obispo Creek Sub-Area) specifically identified by Table 3-5 of the 2019 Basin Plan, as shown in the table below. Objectives shown are annual mean values. Objectives are based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 5. Annual Mean Surface Water Quality Objectives CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 16 Parameter Units Annual Mean Total Dissolved Solids mg/L 650 Chloride mg/L 100 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 5.2. Groundwater Limitations Activities at the Facility shall not cause exceedance/deviation from the following water quality objectives for groundwater established by the 2019 Basin Plan. The Central Coast Water Board may require the Discharger to investigate the cause of exceedances in the groundwater before determining whether the Discharger caused any water condition that exceeds the following groundwater limitations. 5.2.1. Groundwater shall not contain taste or odor-producing substances in concentrations that adversely affect beneficial uses. 5.2.2. Radionuclides shall not be present in concentrations that are deleterious to human, plant, animal, or aquatic life or result in the accumulation of radionuclides in the food web to an extent that presents a hazard to human, plant, animal, or aquatic life. In no circumstances shall groundwater contain concentrations of radionuclides in excess of the MCLs for radioactivity presented in Title 22 California Code of Regulations, division 4, chapter 15, article 5, sections 64442 and 64443. 5.2.3. The Discharger shall not cause a statistically significant increase of mineral constituent concentrations in underlying groundwater as determined by comparison of samples collected from wells located up-gradient and down- gradient of the waters affected by the discharge. 5.2.4. The median concentration of coliform organisms in groundwater, over any seven- day period, shall be less than 2.2 organisms per 100 mL. 5.2.5. Groundwater shall not contain concentrations of chemical constituents in excess of the primary MCLs specified for drinking water in Table 64431-A (Primary MCLs for Inorganic Chemicals) and Table 64444-A (Primary MCLs for Organic Chemicals) of title 22 California Code of Regulations, division 4, chapter 15. 5.2.6. Groundwater shall not contain concentrations of chemical constituents in amounts that adversely affect the agricultural supply beneficial use. Interpretation of adverse effects shall be as derived in University of California Agricultural Extension Service guidelines provided in Table 3-1 of the 2019 Basin Plan. 5.2.7. Groundwater used for irrigation and livestock watering shall not exceed concentrations of chemical constituents in excess of those levels specified for irrigation and livestock watering in chapter 3, Table 3-2 of the 2019 Basin Plan. 5.2.8. Groundwater shall not contain constituents greater than the following concentrations established in Table 3-6 of the 2019 Basin Plan for groundwaters within the San Luis Obispo Creek sub-area (Estero Bay sub-basin). Objectives CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 17 shown are annual median values. Objectives based on preservation of existing quality or water quality enhancement believed attainable following control of point sources. Table 6. Groundwater Objectives Parameter Units Annual Median TDS mg/L 900 Chloride mg/L 200 Sulfate mg/L 100 Boron mg/L 0.2 Sodium mg/L 50 Nitrogen mg/L 5 6. PROVISIONS 6.1. Standard Provisions 6.1.1. The Discharger shall comply with all Standard Provisions included in Attachment D. 6.1.2. The Discharger shall comply with Central Coast Water Board Standard Provisions in Attachment D. In the event that there is any conflict, duplication, or overlap between provisions specified by this Order, the more stringent provision shall apply. 6.2. Monitoring and Reporting Program (MRP) Requirements The Discharger shall comply with the MRP, and future revisions thereto, in Attachment E. 6.3. Special Provisions 6.3.1. Reopener Provisions 6.3.1.1. This Order may be reopened for modification, or revocation and reissuance, as a result of the detection of a reportable priority pollutant generated by special conditions included in this Order. These special conditions may be, but are not limited to, fish tissue sampling, whole effluent toxicity, monitoring requirements on internal waste stream(s), monitoring for surrogate parameters, and other new information. Additional requirements may be included in this Order as a result of the special condition monitoring data. 6.3.1.2. This Order may be reopened and modified in accordance with NPDES regulations at 40 Code of Federal Regulations (CFR) parts 122 and 124, as necessary, to include additional conditions or limitations based on newly available information or to implement any U.S. EPA approved, new, state water quality objective. 6.3.1.3. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 18 to cause, or contributes to an excursion above a State Implementation Policy (SIP) water quality objective. 6.3.1.4. This Order may be reopened and modified to revise the most sensitive species to be used for acute and/or chronic aquatic toxicity testing once the required species sensitivity is completed in accordance with section 5 of the MRP (Attachment E). Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. 6.3.1.5 This Order may be reopened and modified to reevaluate reasonable potential for acute toxicity, and establish acute toxicity effluent limitations, if warranted, after the evaluation of new data and information. 6.3.2. Special Studies, Technical Papers and Additional Monitoring Requirements 6.3.2.1. Toxicity Reduction Requirements For compliance with the Basin Plan’s narrative toxicity objective, this Order requires the Discharger to conduct acute and chronic whole effluent toxicity (WET) testing, as specified in section 5 of the MRP. Furthermore, this Provision requires the Discharger to investigate the causes of and identify corrective actions to reduce or eliminate effluent toxicity. If the discharge exceeds the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring established in this Provision, the Discharger is required to initiate a Toxicity Reduction Evaluation (TRE) in accordance with an approved TRE Work Plan and take actions to mitigate the impact of the discharge and prevent recurrence of toxicity. A TRE is a site-specific study conducted in a stepwise process to identify the source(s) of toxicity and the effective control measures for effluent toxicity. TREs are designed to identify the causative agents and sources of whole effluent toxicity, evaluate the effectiveness of the toxicity control options, and confirm the reduction in effluent toxicity. This Provision includes requirements for the Discharger to update and submit their TRE Work Plan and includes procedures for accelerated toxicity monitoring and TRE initiation: 6.3.2.1.1. TRE Work Plan. Within 90 days of the effective date of this Order, the Discharger shall submit to the Central Coast Water Board an updated TRE Work Plan for approval by the Executive Officer. The TRE Work Plan shall outline the procedures for identifying the source(s) of and reducing or eliminating effluent toxicity. The TRE Work Plan must be developed in accordance with U.S. EPA guidance and be of adequate detail to allow the Discharger to immediately initiate a TRE as required in this Provision. 6.3.2.1.2. Accelerated Monitoring and TRE Initiation. When the numeric toxicity monitoring trigger or effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all test acceptability criteria (TAC), the Discharger shall initiate accelerated monitoring as required in the Accelerated Monitoring Specifications in section 5 of the MRP. The Discharger shall initiate a TRE to address effluent toxicity if any WET testing results exceed CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 19 the numeric toxicity monitoring trigger or effluent limitation during accelerated monitoring. 6.3.3. Best Management Practices and Pollution Prevention 6.3.3.1. Salt and Nutrient Management Program 6.3.3.1.1 The Discharger shall continue to update and implement an ongoing Salt Management Program, with the intent of reducing mass loading of salts in treated effluent and attainment of applicable water quality objectives for salts in the San Luis Obispo Creek Sub-Basin Area of the Estero Bay Drainage Basin. Additionally, the Discharger shall continue to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable water quality objectives for nutrients in the same basin. 6.3.3.1.2 Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. 6.3.3.1.3 Nutrient reduction measures shall focus on optimizing wastewater treatment processes for nitrification and denitrification, or other means of nitrogen removal. Reduction measures may also include source control (non-human waste from commercial and industrial sources) as appropriate. 6.3.3.1.4 As part of the Salt and Nutrient Management Program, the Discharger shall submit an annual report describing salt and nutrient reduction efforts as described in the section 9.3 of the MRP (Attachment E). 6.3.3.1.5 As an alternative to the Salt and Nutrient Management Program requirements described above, upon Executive Officer approval, the Discharger may submit documentation and summary of participation in a regional salt/nutrient management plan implemented under the provisions of State Water Board Resolution No. 2018-0057 (Recycled Water Policy). 6.3.3.2. Pollutant Minimization Program 6.3.3.2.1.The Discharger shall develop and conduct a Pollutant Minimization Program (PMP) as further described below when there is evidence (e.g., sample results reported as detected not quantifiable (DNQ) when the effluent limitation is less than the MDL, sample results from analytical methods more sensitive than those methods required by this Order, presence of whole effluent toxicity, health advisories for fish consumption, results of benthic or aquatic organism tissue sampling) that a priority pollutant is present in the effluent above an effluent limitation and either: 6.3.3.2.1.1. A sample result is reported as DNQ and the effluent limitation is less than the reporting limit (RL); or 6.3.3.2.1.2. A sample result is reported as non-detect (ND) and the effluent limitation is less than the MDL, using definitions described in Attachment A and reporting protocols described in MRP section 10.2.4. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 20 6.3.3.2.2. The PMP shall include, but not be limited to, the following actions and submittals acceptable to the Central Coast Water Board Executive Officer: 6.3.3.2.2.1. An annual review and semi-annual monitoring of potential sources of the reportable priority pollutant(s), which may include fish tissue monitoring and other bio-uptake sampling; 6.3.3.2.2.2. Quarterly monitoring for the reportable priority pollutant(s) in the influent to the wastewater treatment system; 6.3.3.2.2.3. Submittal of a control strategy designed to proceed toward the goal of maintaining concentrations of the reportable priority pollutant(s) in the effluent at or below the effluent limitation; 6.3.3.2.2.4. Implementation of appropriate cost-effective control measures for the reportable priority pollutant(s), consistent with the control strategy; and 6.3.3.1.2.5. An annual status report that shall be sent to the Central Coast Water Board including: 6.3.3.1.2.5.1. All PMP monitoring results for the previous year; 6.3.3.1.2.5.2. A list of potential sources of the reportable priority pollutant(s); 6.3.3.1.2.5.3. A summary of all actions undertaken pursuant to the control strategy; and 6.3.3.1.2.5.4. A description of actions to be taken in the following year. 6.3.4. Construction, Operation and Maintenance Specifications 6.3.4.1. The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.3.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.3.5.1. Biosolids. The handling, management, and disposal of sludge and solids derived from wastewater treatment must comply with applicable provisions of U.S. EPA regulations at 40 CFR sections 257, 258, 501, and 503, including all monitoring, record keeping, and reporting requirements. Solids and sludge treatment, storage, and disposal or reuse shall not create a nuisance, such as objectionable odors or flies, and shall not result in ground water contamination. Sites for solids and sludge treatment and storage shall have adequate facilities to divert surface water runoff from adjacent areas to protect the boundaries of such sites from erosion, and to prevent drainage from treatment and storage sites. The treatment, storage, disposal, or reuse of sewage sludge and solids shall not cause waste material to be in a position where it is, or can be, conveyed from the treatment and storage sites and deposited into waters of the State. The Discharger is responsible for assuring that all biosolids produced at its facility are used or disposed of in accordance with the above rules, regardless of whether the Discharger uses or disposes of the biosolids itself, or transfers them to another party for further treatment, use, or disposal. The Discharger is CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 21 responsible for informing subsequent preparers, appliers, and disposers of the requirements that they must adhere to these rules. 6.3.5.2. Pretreatment. The Discharger shall be responsible for the performance for all pretreatment requirements contained in 40 CFR part 403 and shall be subject to enforcement actions, penalties, fines, and other remedies by the U.S. EPA, or other appropriate parties, as provided in the CWA, as amended (33 USC 1351 et seq.). The Discharger shall implement and enforce its approved POTW Pretreatment Program. The Discharger’s approved POTW Pretreatment Program is hereby made an enforceable condition of this permit. U.S. EPA or the Central Coast Water Board may initiate enforcement action against an industrial user for noncompliance with applicable standards and requirements as provided in the CWA. The Discharger shall enforce the requirements promulgated under sections 307 (b), 307 (c), 307 (d), and 402 (b) of the CWA. The Discharger shall cause industrial users subject to Federal Categorical Standards to achieve compliance no later than the date specified in those requirements or, in the case of a new industrial user, upon commencement of the discharge. The Discharger shall perform the pretreatment functions as required in 40 CFR part 403, including, but not limited to the following: 6.3.5.2.1. Implement the necessary authorities as provided in 40 CFR section 403.8 (f) (1); 6.3.5.2.2. Enforce the pretreatment requirements under 40 CFR sections 403.5 and 403.6; 6.3.5.2.3. Implement the programmatic functions as provided in 40 CFR section 403.8 (f) (2); and 6.3.5.2.4. Provide the requisite funding and personnel to implement the pretreatment program as provided in 40 CFR section 403.8 (f) (3). 6.3.5.5. Resource Recovery from Anaerobically Digestible Material. If the Discharger will receive hauled-in anaerobically digestible material for injection into an anaerobic digester, the Discharger shall notify the Central Coast Water Board and develop and implement standard operating procedures for this activity. The standard operating procedures shall be developed prior to receiving hauled-in anaerobically digestible material. The standard operating procedures shall address material handling, including unloading, screening, or other processing prior to anaerobic digestion; transportation; spill prevention; and spill response. In addition, the standard operating procedures shall address avoidance of the introduction of materials that could cause interference, pass- through, or upset of the treatment processes; avoidance of prohibited material; vector control; odor control; operation and maintenance; and the disposition of any solid waste segregated from introduction to the digester. The Discharger shall train its staff on the standard operating procedures and shall maintain records for a minimum of five years for each load received, describing the hauler, waste type, and quantity received. In addition, the Discharger shall CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 22 maintain records for a minimum of five years for the disposition, location, and quantity of cumulative pre-digestion-segregated solid waste hauled offsite. 6.3.6. Other Special Provisions 6.3.6.1. Salt Management. Salt reduction measures shall focus on all potential salt contributors to the collection system, including water supply, commercial, industrial, and residential dischargers. The Discharger shall assess additional pretreatment measures that may be taken to reduce influent salt concentrations and include a discussion of proposed and implemented measures in the annual report described below. The Discharger must also implement outreach to residential, commercial, and industrial salt contributors with the goal of reducing salts discharged to the collection system. 6.3.6.2. Discharges of Stormwater. For the control of stormwater discharged from the site of the wastewater treatment and disposal facilities, if applicable, the Discharger shall seek authorization to discharge under and meet the requirements of the State Water Board’s Water Quality Order 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Discharges of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.3.6.3. Statewide General Waste Discharge Requirements for Sanitary Sewer Systems (State Water Board Order No. 2022-0103-DWQ) The Discharger is subject to the requirements of and must separately comply with State Water Board Order 2022-0103-DWQ, Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems, including monitoring and reporting requirements, and any subsequent revision to that order. This General Permit, adopted on December 6, 2022, is applicable to all “federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California.” The purpose of the General Permit is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled under the General Permit. 6.3.6.4. Climate Change Adaptation Implementation Progress Report. On May 1, 2029, the Discharger shall submit a Climate Change Adaptation Implementation Progress Report 2 to the Central Coast Water Board Executive Officer describing the Discharger’s progress in implementing, monitoring, and updating its long-term approach for identifying and addressing climate change hazards and vulnerabilities at the Facility, including all associated infrastructure (e.g., treatment facilities, conveyances to discharge points, discharge facilities). 2 In place of a static document, the Discharger may develop a living document and/or set of tools that fulfills the components outlined for the Climate Change Adaptation Program. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 23 The Climate Change Adaptation Implementation Report shall, at a minimum, include the following components: 6.3.6.4.1. Climate Change Adaptation Implementation Status – Provide a status update on any city or county-wide reports that address Facility and or collection system climate change adaptation planning and or implantation. Submit copies of document(s) to CIWQS as attachments. 6.3.6.4.2. Resiliency Actions – Report progress on actions that build facility and operational resilience to identified vulnerabilities, accounting for options that minimize resource impacts. For the anticipated life of the facility, include an analysis of: • Precipitation pattern changes o Drought – Decreased influent quantity and quality o Peak Events – Flooding and increased influent quantity • Temperature fluctuations and extremes • Increased wildfires • Energy resilience o Energy efficiency o Renewable energy generation o Increased power outages • Biosolid reuse • Water recycling 6.3.6.4.3. Adaptation Strategy – Report progress and adjustments made to strategy to complete Resiliency Actions, encompassing the following: 6.3.6.4.3.1. Prioritization – How resiliency actions were prioritized based on risks to water quality, but also accounting for costs and benefits. 6.3.6.4.3.2. Schedule and Milestones – Ongoing and changing timeframes to complete prioritized resiliency actions and/or climate change hazard triggers to inform when the Discharger shall implement actions. Milestones to complete critical steps for prioritized Resiliency Actions, designed to demonstrate measurable progress at a steady, or accelerated, completion pace over the established timeframes. 6.3.6.4.3.3. Financial Planning – Costs of reported implementation and monitoring measures, projected costs necessary to continue implementation and monitoring of resiliency actions, and strategy to procure funds. 6.3.7. Compliance Schedules – Not Applicable 7. COMPLIANCE DETERMINATION 7.1. General Compliance with effluent limitations for reportable pollutants shall be determined using sample reporting protocols defined in the MRP and Attachment A of this Order. For purposes of reporting and administrative enforcement by the Central Coast and State Water Boards, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the reportable pollutant in the CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 24 monitoring sample is greater than the effluent limitation and greater than or equal to the reported Minimum Level (ML). 7.2. Chronic Toxicity The discharge is subject to determination of “Pass” or “Fail” from a chronic toxicity test using the Test of Significant Toxicity (TST) statistical t-test approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. The null hypothesis (Ho) for the TST statistical approach is: Mean discharge “in-stream” waste concentration (IWC) response ≤0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge (100 percent effluent) and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be reported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). 7.3. Multiple Sample Data When determining compliance with a measure of central tendency (arithmetic mean, geometric mean, median, etc.) of multiple samples analyses and the data set contains one or more reported determinations of DNQ, or ND, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 7.3.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 7.3.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 WASTE DISCHARGE REQUIREMENTS 25 even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 7.4. Average Monthly Effluent Limitation (AMEL) If the average of daily discharges over a calendar month exceeds the AMEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that month for that parameter (e.g., resulting in 31 days of non-compliance in a 31-day month). The average of daily discharges over the calendar month that exceeds the AMEL for a parameter will be considered out of compliance for that month only. If only a single sample is taken during the calendar month and the analytical result for that sample exceeds the AMEL, the Discharger will be considered out of compliance for that calendar month. For any one calendar month during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar month. 7.5. Average Weekly Effluent Limitation (AWEL) If the average of daily discharges over a calendar week exceeds the AWEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for each day of that week for that parameter, resulting in seven days of non-compliance. The average of daily discharges over the calendar week that exceeds the AWEL for a parameter will be considered out of compliance for that week only. If only a single sample is taken during the calendar week and the analytical result for that sample exceeds the AWEL, the Discharger will be considered out of compliance for that calendar week. For any one calendar week during which no sample (daily discharge) is taken, no compliance determination can be made for that calendar week. 7.6. Maximum Daily Effluent Limitation (MDEL) If a daily discharge exceeds the MDEL for a given parameter, an alleged violation will be flagged and the Discharger will be considered out of compliance for that parameter for that one day only within the reporting period. For any one day during which no sample is taken, no compliance determination can be made for that day. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-1 A. ATTACHMENT A – DEFINITIONS Arithmetic Mean (μ) Also called the average, is the sum of measured values divided by the number of samples. For ambient water concentrations, the arithmetic mean is calculated as follows: where: Σx is the sum of the measured ambient water concentrations, and n is the number of samples. Average Monthly Effluent Limitation (AMEL) The highest allowable average of daily discharges over a calendar month, calculated as the sum of all daily discharges measured during a calendar month divided by the number of daily discharges measured during that month. Average Weekly Effluent Limitation (AWEL) The highest allowable average of daily discharges over a calendar week (Sunday through Saturday), calculated as the sum of all daily discharges measured during a calendar week divided by the number of daily discharges measured during that week. Bioaccumulative Those substances taken up by an organism from its surrounding medium through gill membranes, epithelial tissue, or from food and subsequently concentrated and retained in the body of the organism. Bioassay A test used to evaluate the relative potency of a chemical or a mixture of chemicals by comparing its effect on a living organism with the effect of a standard preparation on the same type of organism. Calendar Month(s) A period of time from a day of one month to the day before the corresponding day of the next month if the corresponding day exists, or if not to the last day of the next month (e.g., from January 1 to January 31, from June 15 to July 14, or from January 31 to February 28). Calendar Quarter A period of time defined as three consecutive calendar months. Calendar Year A period of time defined as twelve consecutive calendar months. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-2 Carcinogenic Pollutants are substances that are known to cause cancer in living organisms. Chronic Aquatic Toxicity Test A test to determine an adverse effect (sublethal or lethal) on a group of aquatic test organisms during an exposure of duration long enough to assess sub-lethal effects. Compliance with the effluent limitation for chronic toxicity in this Order is demonstrated by conducting chronic toxicity tests for the effluent as described in section 7.15 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E), and in accordance with the TST statistical approach. Coefficient of Variation (CV) CV is a measure of the data variability and is calculated as the estimated standard deviation divided by the arithmetic mean of the observed values. Continuous Dischargers Facilities that discharge without interruption throughout its operating hours, except for infrequent shutdowns for maintenance, process changes, or other similar activities, and that discharge throughout the calendar year. Daily Discharge Daily Discharge is defined as either: (1) the total mass of the constituent discharged over the calendar day (12:00 am through 11:59 pm) or any 24-hour period that reasonably represents a calendar day for purposes of sampling (as specified in the permit), for a constituent with limitations expressed in units of mass or; (2) the unweighted arithmetic mean measurement of the constituent over the day for a constituent with limitations expressed in other units of measurement (e.g., concentration). The daily discharge may be determined by the analytical results of a composite sample taken over the course of one day (a calendar day or other 24-hour period defined as a day) or by the arithmetic mean of analytical results from one or more grab samples taken over the course of the day. For composite sampling, if one day is defined as a 24-hour period other than a calendar day, the analytical result for the 24-hour period will be considered as the result for the calendar day in which the 24-hour period ends. Detected, but Not Quantified (DNQ) DNQ are those sample results less than the reporting limit (RL), but greater than or equal to the laboratory’s MDL. Sample results reported as DNQ are estimated concentrations. Dilution Credit Dilution Credit is the amount of dilution granted to a discharge in the calculation of a water quality-based effluent limitation, based on the allowance of a specified mixing zone. It is calculated from the dilution ratio or determined through conducting a mixing zone study or modeling of the discharge and receiving water. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-3 Dilution Ratio The critical low flow of the upstream receiving water divided by the flow of the effluent discharged. Effluent Concentration Allowance (ECA) ECA is a value derived from the water quality criterion/objective, dilution credit, and ambient background concentration that is used, in conjunction with the coefficient of variation for the effluent monitoring data, to calculate a long-term average (LTA) discharge concentration. The ECA has the same meaning as wasteload allocation (WLA) as used in United States Environmental Protection Agency (U.S. EPA) guidance (Technical Support Document for Water Quality-based Toxics Control, March 1991, second printing, EPA/505/2-90-001). Enclosed Bays Enclosed Bays means indentations along the coast that enclose an area of oceanic water within distinct headlands or harbor works. Enclosed bays include all bays where the narrowest distance between the headlands or outermost harbor works is less than 75 percent of the greatest dimension of the enclosed portion of the bay. Enclosed bays include, but are not limited to, Humboldt Bay, Bodega Harbor, Tomales Bay, Drake’s Estero, San Francisco Bay, Morro Bay, Los Angeles-Long Beach Harbor, Upper and Lower Newport Bay, Mission Bay, and San Diego Bay. Enclosed bays do not include inland surface waters or ocean waters. Estimated Chemical Concentration The estimated chemical concentration that results from the confirmed detection of the substance by the analytical method below the minimum level (ML) value. Estuaries and Coastal Lagoons Estuaries means waters, including coastal lagoons, located at the mouths of streams that serve as areas of mixing for fresh and ocean waters. Coastal lagoons and mouths of streams that are temporarily separated from the ocean by sandbars shall be considered estuaries. Estuarine waters shall be considered to extend from a bay or the open ocean to a point upstream where there is no significant mixing of fresh water and seawater. Estuarine waters included, but are not limited to, the Sacramento-San Joaquin Delta, as defined in California Water Code section 12220, Suisun Bay, Carquinez Strait downstream to the Carquinez Bridge, and appropriate areas of the Smith, Mad, Eel, Noyo, Russian, Klamath, San Diego, and Otay rivers. Estuaries do not include inland surface waters or ocean waters. Flow-Through Acute Toxicity Testing Systems A toxicity testing system where an effluent sample is either pumped continuously from the sampling point directly to a dilutor system, or collected and placed in a tank adjacent to the test laboratory and pumped continuously from the tank to a dilutor system. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-4 Inland Surface Waters All surface waters of the state that do not include the ocean, enclosed bays, or estuaries. Insignificant Dischargers National Pollutant Discharge Elimination System (NPDES) discharges that are determined to be a very low threat to water quality by the permitting authority. Instantaneous Maximum Effluent Limitation The highest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous maximum limitation). Instantaneous Minimum Effluent Limitation The lowest allowable value for any single grab sample or aliquot (i.e., each grab sample or aliquot is independently compared to the instantaneous minimum limitation). In-stream Waste Concentration (IWC) The concentration of effluent in the receiving water after mixing as determined by the permitting authority. For purposes of aquatic toxicity testing for non-stormwater NPDES dischargers, the IWC shall be as described in section III.C.1 of the Toxicity Provisions. For assessing whether receiving waters meet the numeric water quality objectives (WQOs), the undiluted ambient water shall be used as the IWC in the TST as indicated in section III.B.3 of the Toxicity Provisions. Maximum Daily Effluent Limitation (MDEL) The highest allowable daily discharge of a pollutant, over a calendar day (or 24-hour period). For pollutants with limitations expressed in units of mass, the daily discharge is calculated as the total mass of the pollutant discharged over the day. For pollutants with limitations expressed in other units of measurement, the daily discharge is calculated as the arithmetic mean measurement of the pollutant over the day. For the purposes of chronic and acute aquatic toxicity, an MDEL is an effluent limitation based on the outcome of the TST approach and the resulting percent effect at the IWC, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Maximum Daily Effluent Target (MDET) For the purposes of chronic and acute aquatic toxicity, an MDET is a target used to determine whether a Toxicity Reduction Evaluation (TRE) should be conducted. Not meeting the MDET is not a violation of an effluent limitation. Median The middle measurement in a set of data. The median of a set of data is found by first arranging the measurements in order of magnitude (either increasing or decreasing order) If the number of measurements (n) is odd, then: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-5 If n is even, then: (i.e., the midpoint between the (n/2 and ((n/2)+1))). Median Monthly Effluent Limitation (MMEL) For the purposes of chronic and acute aquatic toxicity, an MMEL is an effluent limitation based on a maximum of three independent toxicity tests, analyzed using the TST, as described in sections III.C.5 and III.C.6 of the Toxicity Provisions. Median Monthly Effluent Target (MMET) For the purposes of chronic and acute aquatic toxicity, an MMET is a target based on a maximum of three independent toxicity tests used to determine whether a TRE should be conducted. Not meeting the MMET is not a violation of an effluent limitation. Method Detection Limit (MDL) MDL is the minimum concentration of a substance that can be reported with 99 percent confidence that the measured concentration is distinguishable from method blank results, as defined in 40 Code of Federal Regulations (CFR) part 136, Attachment B. Minimum Level (ML) ML is the concentration at which the entire analytical system must give a recognizable signal and acceptable calibration point. The ML is the concentration in a sample that is equivalent to the concentration of the lowest calibration standard analyzed by a specific analytical procedure, assuming that all the method specified sample weights, volumes, and processing steps have been followed. Mixing Zone Mixing Zone is a limited volume of receiving water that is allocated for mixing with a wastewater discharge where water quality criteria can be exceeded without causing adverse effects to the overall water body. MMEL Compliance Tests For the purposes of chronic and acute aquatic toxicity, MMEL compliance tests are a maximum of two tests that are used in addition to the routine monitoring test to determine compliance with the chronic and acute aquatic toxicity MMEL and MDEL. MMET Tests For the purposes of chronic and acute aquatic toxicity, for dischargers not required to comply with numeric chronic toxicity effluent limitations, MMET tests are a maximum of two tests that are used in addition to the routine monitoring test to determine whether a TRE should be conducted. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-6 Most Sensitive Species The single species selected from an array of test species to be used in a single species laboratory test series to determine toxic effects of effluent or ambient water. Non-Continuous Dischargers Dischargers that do not discharge in a continuous manner or do not discharge throughout the calendar year (e.g., intermittent and seasonal dischargers). Non-NPDES Dischargers Dischargers of waste that could affect the quality of waters of the State that are not regulated by the NPDES program. Non-Stormwater NPDES Dischargers Dischargers that are regulated pursuant to one or more NPDES permit(s), but excluding any discharges subject to the United States Code title 33 section 1342(p). This includes dischargers that discharge a combination of treated municipal or industrial wastewater and stormwater. Nonpoint Source A source that does not meet the definition of a point source, as defined below. Not Detected (ND) Sample results which are less than the laboratory’s MDL. Null Hypothesis A statement used in statistical testing that has been put forward either because it is believed to be true or because it is to be used as a basis for argument, but has not been proved. Ocean Waters The territorial marine waters of the State, as defined by California law, to the extent these waters are outside of enclosed bays, estuaries, and coastal lagoons. Discharges to ocean waters are regulated in accordance with the State Water Board’s California Ocean Plan. Percent Effect The value that denotes the difference in response between the test concentration and the control, divided by the mean control response, and multiplied by 100. Permitting Authority The State Water Board or a regional water board that issues a permit, waste discharge requirements, water quality certification, or other authorization for the discharge or proposed discharge of waste. To the extent that the action is delegable, the term “Permitting Authority” can include the Executive Officer or Executive Director. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-7 Persistent Pollutants Persistent pollutants are substances for which degradation or decomposition in the environment is nonexistent or very slow. Point Source Any discernible, confined and discrete conveyance including, but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from which pollutants are or may be discharged. This term does not include agricultural stormwater discharges and return flows from irrigated agriculture. Pollutant Defined in section 502(6) of the CWA as “dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt and industrial, municipal, and agricultural waste discharged into water.” Pollutant Minimization Program (PMP) PMP means waste minimization and pollution prevention actions that include, but are not limited to, product substitution, waste stream recycling, alternative waste management methods, and education of the public and businesses. The goal of the PMP shall be to reduce all potential sources of a priority pollutant(s) through pollutant minimization (control) strategies, including pollution prevention measures as appropriate, to maintain the effluent concentration at or below the water quality-based effluent limitation. Pollution prevention measures may be particularly appropriate for persistent bioaccumulative priority pollutants where there is evidence that beneficial uses are being impacted. The Central Coast Water Board may consider cost effectiveness when establishing the requirements of a PMP. The completion and implementation of a Pollution Prevention Plan, if required pursuant to California Water Code section 13263.3(d), shall be considered to fulfill the PMP requirements. Pollution Prevention Pollution Prevention means any action that causes a net reduction in the use or generation of a hazardous substance or other pollutant that is discharged into water and includes, but is not limited to, input change, operational improvement, production process change, and product reformulation (as defined in California Water Code section 13263.3). Pollution prevention does not include actions that merely shift a pollutant in wastewater from one environmental medium to another environmental medium, unless clear environmental benefits of such an approach are identified to the satisfaction of the State Water Resources Control Board (State Water Board) or California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board). Publicly Owned Treatment Works (POTW) Facilities owned by a state or municipality that store, treat, recycle, and reclaim municipal sewage or industrial wastes of a liquid nature. Similar facilities that are privately, instead of publicly owned, are included in this definition for purposes of section III of the Toxicity Provisions. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-8 Reasonable Potential A designation used for a waste discharge that is projected or calculated to cause or contribute to an instream excursion above a water quality standard. Regulatory Management Decision (RMD) The decision that represents the maximum allowable error rates and thresholds for toxicity and non-toxicity that would result in an acceptable risk to aquatic life. Replicates Two or more independent organism exposures of the same treatment (i.e., effluent concentration) within a toxicity test. Replicates are typically conducted with separate test chambers and test organisms, each having the same effluent concentration. Reporting Level (RL) The RL is the ML (and its associated analytical method) chosen by the Discharger for reporting and compliance determination from the MLs included in this Order, including an additional factor if applicable as discussed herein. The MLs included in this Order correspond to approved analytical methods for reporting a sample result that are selected by the Central Coast Water Board either from Appendix 4 of the State Implementation Policy (SIP) in accordance with section 2.4.2 of the SIP or established in accordance with section 2.4.3 of the SIP. The ML is based on the proper application of method-based analytical procedures for sample preparation and the absence of any matrix interferences. Other factors may be applied to the ML depending on the specific sample preparation steps employed. For example, the treatment typically applied in cases where there are matrix-effects is to dilute the sample or sample aliquot by a factor of ten. In such cases, this additional factor must be applied to the ML in the computation of the RL. Response A measured biological effect (e.g., survival, reproduction, growth) as a result of exposure to a stimulus. Routine Monitoring Required monitoring that occurs during a permit term. Source of Drinking Water Any water designated as municipal or domestic supply (MUN) in a Central Coast Water Board Water Quality Control Plan for the Central Coastal Basin (Basin Plan). Species Sensitivity Screening An analysis to determine the single most sensitive species from an array of test species to be used in a single species laboratory test series. Standard Deviation (σ) Standard Deviation is a measure of variability that is calculated as follows: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT A – DEFINITIONS A-9 where: x is the observed value; µ is the arithmetic mean of the observed values; and n is the number of samples. Stormwater As defined at 40 C.F.R. section 122.26(b)(13) (Nov. 16, 1990) which states, ‘Storm water means storm water runoff, snow melt runoff, and surface runoff and drainage.” Test of Significant Toxicity (TST) A statistical approach used to analyze aquatic toxicity test data, as described in section IV.B.1.c of the Toxicity Provisions. Toxicity Identification Evaluation (TIE) Techniques used to identity the unexplained cause(s) of toxic event. A TIE involves selectively removing classes of chemicals through a series of sample manipulations, effectively reducing complex mixtures of chemicals in natural waters to simple components for analysis. Following each manipulation, the toxicity sample is assessed to see whether the toxicant class removed was responsible for the toxicity. Toxicity Reduction Evaluation (TRE) TRE is a study conducted in a step-wise process designed to identify the causative agents of effluent or ambient toxicity, isolate the sources of toxicity, evaluate the effectiveness of toxicity control options, and then confirm the reduction in toxicity. The first steps of the TRE consist of the collection of data relevant to the toxicity, including additional toxicity testing, and an evaluation of facility operations and maintenance practices, and best management practices. A Toxicity Identification Evaluation (TIE) may be required as part of the TRE, if appropriate. (A TIE is a set of procedures to identify the specific chemical(s) responsible for toxicity. These procedures are performed in three phases (characterization, identification, and confirmation) using aquatic organism toxicity tests.) Toxicity Provisions Refers to State Policy for Water Quality Control: Toxicity Provisions (adopted in 2020 and revised in 2021) of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT B-MAP B-1 B. ATTACHMENT B – MAP CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-1 C. ATTACHMENT C – FLOW SCHEMATIC CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT C – FLOW SCHEMATIC C-2 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-1 D. ATTACHMENT D – STANDARD PROVISIONS 1. STANDARD PROVISIONS – PERMIT COMPLIANCE 1.1. Duty to Comply 1.1.1. The Discharger must comply with all terms, requirements, and conditions of this Order. Any noncompliance constitutes a violation of the Clean Water Act (CWA) and the California Water Code (Water Code) and is grounds for enforcement action; permit termination, revocation and reissuance, or modification; denial of a permit renewal application; or a combination thereof. (40 Code of Federal Regulations (C.F.R.) 122.41(a); Water Code sections 13261, 13263, 13265, 13268, 13000, 13001, 13304, 13350, 13385.) 1.1.2. The Discharger shall comply with effluent standards or prohibitions established under Section 307(a) of the CWA for toxic pollutants within the time provided in the regulations that establish these standards or prohibitions, even if this Order has not yet been modified to incorporate the requirement. (40 C.F.R. 122.41(a)(1).) 1.2. Need to Halt or Reduce Activity Not a Defense It shall not be a defense for a Discharger in an enforcement action that it would have been necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this Order. (40 C.F.R. 122.41(c).) 1.3. Duty to Mitigate The Discharger shall take all reasonable steps to minimize or prevent any discharge in violation of this Order that has a reasonable likelihood of adversely affecting human health or the environment. (40 C.F.R. 122.41(d).) 1.4. Proper Operation and Maintenance The Discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the Discharger to achieve compliance with the conditions of this Order. Proper operation and maintenance also include adequate laboratory controls and appropriate quality assurance procedures. This provision requires the operation of backup or auxiliary facilities or similar systems that are installed by a Discharger only when necessary to achieve compliance with the conditions of this Order. (40 C.F.R. 122.41(e).) 1.5. Property Rights 1.5.1. This Order does not convey any property rights of any sort or any exclusive privileges. (40 C.F.R. 122.41(g).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-2 1.5.2. The issuance of this Order does not authorize any injury to persons or property or invasion of other private rights, or any infringement of state or local law or regulations. (40 C.F.R. 122.5(c).) 1.6. Inspection and Entry The Discharger shall allow the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board), State Water Resources Control Board (State Water Board), United States Environmental Protection Agency (U.S. EPA), and/or their authorized representatives (including an authorized contractor acting as their representative), upon the presentation of credentials and other documents, as may be required by law, to (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i); Water Code sections 13267, 13383): 1.6.1. Enter upon the Discharger's premises where a regulated facility or activity is located or conducted, or where records are kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(i); 40 C.F.R. 122.41(i)(1); Water Code sections 13267, 13383); 1.6.2. Have access to and copy, at reasonable times, any records that must be kept under the conditions of this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(2); Water Code sections 13267, 13383); 1.6.3. Inspect and photograph, at reasonable times, any facilities, equipment (including monitoring and control equipment), practices, or operations regulated or required under this Order (33 U.S.C. 1318(a)(4)(B)(ii); 40 C.F.R. 122.41(i)(3); Water Code sections 13267, 13383); and 1.6.4. Sample or monitor, at reasonable times, for the purposes of assuring Order compliance or as otherwise authorized by the CWA or the Water Code, any substances or parameters at any location. (33 U.S.C. 1318(a)(4)(B); 40 C.F.R. 122.41(i)(4); Water Code sections 13267, 13383.) 1.7. Bypass 1.7.1. Definitions 1.7.1.1. “Bypass” means the intentional diversion of waste streams from any portion of a treatment facility. (40 C.F.R. 122.41(m)(1)(i).) 1.7.1.2. “Severe property damage” means substantial physical damage to property, damage to the treatment facilities, which causes them to become inoperable, or substantial and permanent loss of natural resources that can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production. (40 C.F.R. 122.41(m)(1)(ii).) 1.7.2. Bypass not exceeding limitations. The Discharger may allow any bypass to occur which does not cause exceedances of effluent limitations, but only if it is for essential maintenance to assure efficient operation. These bypasses are not subject to the provisions listed in Standard Provisions – Permit Compliance 1.7.3, 1.7.4, and 1.7.5 below. (40 C.F.R. 122.41(m)(2).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-3 1.7.3. Prohibition of bypass. Bypass is prohibited, and the Central Coast Water Board may take enforcement action against a Discharger for bypass, unless (40 C.F.R. 122.41(m)(4)(i)): 1.7.3.1. Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage (40 C.F.R. 122.41(m)(4)(i)(A)); 1.7.3.2. There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass that occurred during normal periods of equipment downtime or preventive maintenance (40 C.F.R. 122.41(m)(4)(i)(B)); and 1.7.3.3. The Discharger submitted notice to the Central Coast Water Board as required under Standard Provisions – Permit Compliance 1.7.5 below. (40 C.F.R. 122.41(m)(4)(i)(C).) 1.7.4. The Central Coast Water Board may approve an anticipated bypass, after considering its adverse effects, if the Central Coast Water Board determines that it will meet the three conditions listed in Standard Provisions – Permit Compliance 1.7.3 above. (40 C.F.R. 122.41(m)(4)(ii).) 1.7.5. Notice 1.7.5.1. Anticipated bypass. If the Discharger knows in advance of the need for a bypass, it shall submit prior notice, if possible, at least 10 days before the date of the bypass. The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part127. (40 C.F.R. 122.41(m)(3)(i).) 1.7.5.2. Unanticipated bypass. The Discharger shall submit a notice of an unanticipated bypass as required in Standard Provisions - Reporting 5.5 below (24-hour notice). The notice shall be sent to the Central Coast Water Board. As of December 21, 2023, all notices must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 below. Notices shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(m)(3)(ii).) 1.8. Upset Upset means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the Discharger. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. (40 C.F.R. 122.41(n)(1).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-4 1.8.1. Effect of an upset. An upset constitutes an affirmative defense to an action brought for noncompliance with such technology-based permit effluent limitations if the requirements of Standard Provisions – Permit Compliance 1.8.2 below are met. No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review. (40 C.F.R. 122.41(n)(2).) 1.8.2 Conditions necessary for a demonstration of upset. A Discharger who wishes to establish the affirmative defense of upset shall demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that (40 C.F.R. 122.41(n)(3)): 1.8.2.1. An upset occurred and that the Discharger can identify the cause(s) of the upset (40 C.F.R. 122.41(n)(3)(i)); 1.8.2.2. The permitted facility was, at the time, being properly operated (40 C.F.R. 122.41(n)(3)(ii)); 1.8.2.3. The Discharger submitted notice of the upset as required in Standard Provisions – Reporting 5.5.2.2 below (24-hour notice) (40 C.F.R. 122.41(n)(3)(iii)); and 1.8.2.4. The Discharger complied with any remedial measures required under Standard Provisions – Permit Compliance 1.3 above. (40 C.F.R. 122.41(n)(3)(iv).) 1.8.3. Burden of proof. In any enforcement proceeding, the Discharger seeking to establish the occurrence of an upset has the burden of proof. (40 C.F.R. 122.41(n)(4).) 2. STANDARD PROVISIONS – PERMIT ACTION 2.1. General This Order may be modified, revoked and reissued, or terminated for cause. The filing of a request by the Discharger for modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not stay any Order condition. (40 C.F.R. 122.41(f).) 2.2. Duty to Reapply If the Discharger wishes to continue an activity regulated by this Order after the expiration date of this Order, the Discharger must apply for and obtain a new permit. (40 C.F.R. 122.41(b).) 2.3. Transfers This Order is not transferable to any person except after notice to the Central Coast Water Board. The Central Coast Water Board may require modification or revocation and reissuance of the Order to change the name of the Discharger and incorporate such other requirements as may be necessary under the CWA and the Water Code. (40 C.F.R. 122.41(l)(3), 122.61.) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-5 3. STANDARD PROVISIONS – MONITORING 3.1. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. (40 C.F.R. 122.41(j)(1).) 3.2. Monitoring must be conducted according to test procedures approved under 40 C.F.R. part 136 for the analyses of pollutants unless another method is required under 40 C.F.R. chapter 1, subchapter N. Monitoring must be conducted according to sufficiently sensitive test methods approved under 40 C.F.R. part 136 for the analysis of pollutants or pollutant parameters or as required under 40 C.F.R. chapter 1, subchapter N. For the purposes of this paragraph, a method is sufficiently sensitive when: 3.2.1. The method minimum level (ML) is at or below the level of the most stringent effluent limitation established in the permit for the measured pollutant or pollutant parameter, and either the method ML is at or below the level of the most stringent applicable water quality criterion for the measured pollutant or pollutant parameter or the method ML is above the applicable water quality criterion but the amount of the pollutant or pollutant parameter in the facility’s discharge is high enough that the method detects and quantifies the level of the pollutant or pollutant parameter in the discharge; or 3.2.2. The method has the lowest ML of the analytical methods approved under 40 C.F.R. part 136 or required under 40 C.F.R. chapter 1, subchapter N for the measured pollutant or pollutant parameter. In the case of pollutants or pollutant parameters for which there are no approved methods under 40 C.F.R. part 136, or otherwise required under 40 C.F.R. chapter 1, subchapter N, monitoring must be conducted according to a test procedure specified in this Order for such pollutants or pollutant parameters. (40 C.F.R. 122.21(e)(3), 122.41(j)(4), 122.44(i)(1)(iv).) 4. STANDARD PROVISIONS – RECORDS 4.1. The Discharger shall retain records of all monitoring information, including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation, copies of all reports required by this Order, and records of all data used to complete the application for this Order, for a period of at least three (3) years from the date of the sample, measurement, report or application. This period may be extended by request of the Central Coast Water Board Executive Officer at any time. (40 C.F.R. 122.41(j)(2).) 4.2. Records of monitoring information shall include: 4.2.1. The date, exact place, and time of sampling or measurements (40 C.F.R. 122.41(j)(3)(i)); 4.2.2. The individual(s) who performed the sampling or measurements (40 C.F.R. 122.41(j)(3)(ii)); 4.2.3. The date(s) analyses were performed (40 C.F.R. 122.41(j)(3)(iii)); CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-6 4.2.4. The individual(s) who performed the analyses (40 C.F.R. 122.41(j)(3)(iv)); 4.2.5. The analytical techniques or methods used (40 C.F.R. 122.41(j)(3)(v)); and 4.2.6. The results of such analyses. (40 C.F.R. 122.41(j)(3)(vi).) 4.3. Claims of confidentiality for the following information will be denied (40 C.F.R. 122.7(b)): 4.3.1. The name and address of any permit applicant or Discharger (40 C.F.R. 122.7(b)(1)); and 4.3.2. Permit applications and included attachments, permits, and effluent data. (40 C.F.R. 122.7(b)(2).) 5. STANDARD PROVISIONS – REPORTING 5.1. Duty to Provide Information The Discharger shall furnish to the Central Coast Water Board, State Water Board, or U.S. EPA within a reasonable time, any information which the Central Coast Water Board, State Water Board, or U.S. EPA may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this Order or to determine compliance with this Order. Upon request, the Discharger shall also furnish to the Central Coast Water Board, State Water Board, or U.S. EPA copies of records required to be kept by this Order. (40 C.F.R. 122.41(h); Water Code sections 13267, 13383.) 5.2. Signatory and Certification Requirements 5.2.1. All applications, reports, or information submitted to the Central Coast Water Board, State Water Board, and/or U.S. EPA shall be signed and certified in accordance with Standard Provisions – Reporting 5.2.2, 5.2.3, 5.2.4, 5.2.5, and 5.2.6 below. (40 C.F.R. 122.41(k).) 5.2.2. All permit applications shall be signed by a responsible corporate officer. For the purpose of this section, a responsible corporate officer means: (i) A president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy- or decision- making functions for the corporation, or (ii) the manager of one or more manufacturing, production, or operating facilities, provided, the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmental compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures. (40 C.F.R. 122.22(a)(1).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-7 5.2.3. All reports required by this Order and other information requested by the Central Coast Water Board, State Water Board, or U.S. EPA shall be signed by a person described in Standard Provisions – Reporting 5.2.2 above, or by a duly authorized representative of that person. A person is a duly authorized representative only if: 5.2.3.1. The authorization is made in writing by a person described in Standard Provisions – Reporting 5.2.2 above (40 C.F.R. 122.22(b)(1)); 5.2.3.2. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the company. (A duly authorized representative may thus be either a named individual or any individual occupying a named position.) (40 C.F.R. 122.22(b)(2)); and 5.2.3.3. The written authorization is submitted to the Central Coast Water Board and State Water Board. (40 C.F.R. 122.22(b)(3).) 5.2.4. If an authorization under Standard Provisions – Reporting 5.2.3 above is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of Standard Provisions – Reporting 5.2.3 above must be submitted to the Central Coast Water Board and State Water Board prior to or together with any reports, information, or applications, to be signed by an authorized representative. (40 C.F.R. 122.22(c).) 5.2.5. Any person signing a document under Standard Provisions – Reporting 5.2.2 or 5.2.3 above shall make the following certification: “I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.” (40 C.F.R. 122.22(d).) 5.2.6. Any person providing the electronic signature for documents described in Standard Provisions – 5.2.1, 5.2.2, or 5.2.3 that are submitted electronically shall meet all relevant requirements of Standard Provisions – Reporting 5.2, and shall ensure that all relevant requirements of 40 C.F.R. part 3 (Cross-Media Electronic Reporting) and 40 C.F.R. part 127 (NPDES Electronic Reporting Requirements) are met for that submission. (40 C.F.R 122.22(e).) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-8 5.3. Monitoring Reports 5.3.1. Monitoring results shall be reported at the intervals specified in the Monitoring and Reporting Program (Attachment E) in this Order. (40 C.F.R. 122.41(l)(4).) 5.3.2. Monitoring results must be reported on a Discharge Monitoring Report (DMR) form or forms provided or specified by the Central Coast Water Board or State Water Board. All reports and forms must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 and comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. (40 C.F.R. 122.41(l)(4)(i).) 5.3.3. If the Discharger monitors any pollutant more frequently than required by this Order using test procedures approved under 40 C.F.R. part 136, or another method required for an industry-specific waste stream under 40 C.F.R. chapter 1, subchapter N, the results of such monitoring shall be included in the calculation and reporting of the data submitted in the DMR or reporting form specified by the Central Coast Water Board or State Water Board. (40 C.F.R. 122.41(l)(4)(ii).) 5.3.4. Calculations for all limitations, which require averaging of measurements, shall utilize an arithmetic mean unless otherwise specified in this Order. (40 C.F.R. 122.41(l)(4)(iii).) 5.4. Compliance Schedules Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule of this Order, shall be submitted no later than 14 days following each schedule date. (40 C.F.R. 122.41(l)(5).) 5.5. Twenty-Four Hour Reporting 5.5.1. The Discharger shall report any noncompliance which may endanger health or the environment. Any information shall be provided orally within 24 hours from the time the Discharger becomes aware of the circumstances. A report shall also be provided within five (5) days of the time the Discharger becomes aware of the circumstances. The report shall contain a description of the noncompliance and its cause; the period of noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports must include the data described above (with the exception of time of discovery) as well as the type of event (i.e., combined sewer overflow, sanitary sewer overflow, or bypass event), type of overflow structure (e.g., manhole, combined sewer overflow outfall), discharge volume untreated by the treatment works treating domestic sewage, types of human health and environmental impacts of the event, and whether the noncompliance was related to wet weather. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-9 As of December 21, 2023, all reports related to combined sewer overflows, sanitary sewer overflows, or bypass events must be submitted to the Central Coast Water Board and must be submitted electronically to the initial recipient defined in Standard Provisions – Reporting 5.10 The reports shall comply with 40 C.F.R. part 3, 40 C.F.R. 122.22, and 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(6)(i).) 5.5.2. The following shall be included as information that must be reported within 24 hours: 5.5.2.1. Any unanticipated bypass that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(A).) 5.5.2.2. Any upset that exceeds any effluent limitation in this Order. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.5.3. The Central Coast Water Board may waive the above required written report on a case-by-case basis if an oral report has been received within 24 hours. (40 C.F.R. 122.41(l)(6)(ii)(B).) 5.6. Planned Changes The Discharger shall give notice to the Central Coast Water Board as soon as possible of any planned physical alterations or additions to the permitted facility. Notice is required under this provision only when (40 C.F.R. 122.41(l)(1)): 5.6.1. The alteration or addition to a permitted facility may meet one of the criteria for determining whether a facility is a new source in section 122.29(b) (40 C.F.R. 122.41(l)(1)(i)); or 5.6.2. The alteration or addition could significantly change the nature or increase the quantity of pollutants discharged. This notification applies to pollutants that are not subject to effluent limitations in this Order. (40 C.F.R. 122.41(l)(1)(ii).); or 5.7. Anticipated Noncompliance The Discharger shall give advance notice to the Central Coast Water Board of any planned changes in the permitted facility or activity that may result in noncompliance with this Order’s requirements. (40 C.F.R. 122.41(l)(2).) 5.8. Other Noncompliance The Discharger shall report all instances of noncompliance not reported under Standard Provisions – Reporting 5.3, 5.4, and 5.5 above at the time monitoring reports are submitted. The reports shall contain the information listed in Standard Provision – Reporting 5.5 above. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypass events, these reports shall contain the information described in Standard Provision – Reporting 5.5 and the applicable required data in appendix A to 40 C.F.R. part 127. The Central Coast Water Board may also require the Discharger to electronically submit reports not CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-10 related to combined sewer overflows, sanitary sewer overflows, or bypass events under this section. (40 C.F.R. 122.41(l)(7).) 5.9 Other Information When the Discharger becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or in any report to the Central Coast Water Board, State Water Board, or U.S. EPA, the Discharger shall promptly submit such facts or information. (40 C.F.R. 122.41(l)(8).) 5.10. Initial Recipient for Electronic Reporting Data The owner, operator, or the duly authorized representative is required to electronically submit NPDES information specified in appendix A to 40 C.F.R. part 127 to the initial recipient defined in 40 C.F.R. section 127.2(b). U.S. EPA will identify and publish the list of initial recipients on its website and in the Federal Register, by state and by NPDES data group [see 40 C.F.R. 127.2(c)]. U.S. EPA will update and maintain this listing. (40 C.F.R. 122.41(l)(9).) 6. STANDARD PROVISIONS – ENFORCEMENT 6.1. The Central Coast Water Board is authorized to enforce the terms of this permit under several provisions of the Water Code, including, but not limited to, sections 13268, 13350, 13385, 13386, and 13387. 7. ADDITIONAL PROVISIONS – NOTIFICATION LEVELS 7.1. Non-Municipal Facilities Existing manufacturing, commercial, mining, and silvicultural Dischargers shall notify the Central Coast Water Board as soon as they know or have reason to believe (40 C.F.R. 122.42(a)): 7.1.1. That any activity has occurred or will occur that would result in the discharge, on a routine or frequent basis, of any toxic pollutant that is not limited in this Order, if that discharge will exceed the highest of the following "notification levels" (40 C.F.R. 122.42(a)(1)): 7.1.1.1. 100 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(1)(i)); 7.1.1.2. 200 μg/L for acrolein and acrylonitrile; 500 μg/L for 2,4 dinitrophenol and 2-methyl 4,6 dinitrophenol; and 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(1)(ii)); 7.1.1.3. Five (5) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(1)(iii)); or 7.1.1.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(1)(iv).) 7.1.2. That any activity has occurred or will occur that would result in the discharge, on a non-routine or infrequent basis, of any toxic pollutant that is not limited in this CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-11 Order, if that discharge will exceed the highest of the following “notification levels" (40 C.F.R. 122.42(a)(2)): 7.1.2.1. 500 micrograms per liter (μg/L) (40 C.F.R. 122.42(a)(2)(i)); 7.1.2.2. 1 milligram per liter (mg/L) for antimony (40 C.F.R. 122.42(a)(2)(ii)); 7.1.2.3. Ten (10) times the maximum concentration value reported for that pollutant in the Report of Waste Discharge (40 C.F.R. 122.42(a)(2)(iii)); or 7.1.2.4. The level established by the Central Coast Water Board in accordance with section 122.44(f). (40 C.F.R. 122.42(a)(2)(iv).) 7.2 Publicly Owned Treatment Works (POTWs) All POTWs shall provide adequate notice to the Central Coast Water Board of the following (40 C.F.R. 122.42(b)): 7.2.1. Any new introduction of pollutants into the POTW from an indirect discharger that would be subject to sections 301 or 306 of the CWA if it were directly discharging those pollutants (40 C.F.R. 122.42(b)(1)); and 7.2.2. Any substantial change in the volume or character of pollutants being introduced into that POTW by a source introducing pollutants into the POTW at the time of adoption of the Order. (40 C.F.R. 122.42(b)(2).) 7.2.3. Adequate notice shall include information on the quality and quantity of effluent introduced into the POTW as well as any anticipated impact of the change on the quantity or quality of effluent to be discharged from the POTW. (40 C.F.R. 122.42(b)(3).) 8. CENTRAL COAST WATER BOARD STANDARD PROVISIONS 8.1. Central Coast Standard Provision – Prohibitions 8.1.1. Introduction of “incompatible wastes” to the treatment system is prohibited. 8.1.2. Discharge of high-level radiological waste and of radiological, chemical, and biological warfare agents is prohibited. 8.1.3. Discharge of “toxic pollutants” in violation of effluent standards and prohibitions established under section 307(a) of the CWA is prohibited. 8.1.4. Discharge of sludge, sludge digester or thickener supernatant, and sludge drying bed leachate to drainageways, surface waters, or the ocean is prohibited. 8.1.5. Introduction of pollutants into the collection, treatment, or disposal system by and “indirect discharger” that: 8.1.5.1. Inhibit or disrupt the treatment process, system operation, or the eventual use or disposal of sludge; or, 8.1.5.2. Flow through the system to the receiving water untreated; and, 8.1.5.3. Cause or “significantly contribute” to a violation of any requirement of this Order, is prohibited. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-12 8.1.6. Introduction of “pollutant free” wastewater to the collection, treatment, and disposal system in amounts that threaten compliance with this order is prohibited. 8.2. Central Coast Standard Provisions 8.2.1. Collection, treatment, and discharge of waste shall not create a nuisance or pollution, as defined by Water Code section 13050. 8.2.2. All facilities used for transport or treatment of wastes shall be adequately protected from inundation and washout as the result of a 100-year frequency flood. 8.2.3. Operation of collection, treatment, and disposal systems shall be in a manner that precludes public contact with wastewater. 8.2.4. Collected screenings, sludges, and other solids removed from liquid wastes shall be disposed in a manner approved by the Executive Officer. 8.2.5. Publicly owned wastewater treatment plans shall be supervised and operated by persons possessing certificates of appropriate grade pursuant to title 23 of the California Administrative Code. 8.2.6. After notice and opportunity for a hearing, this order may be terminated for cause, including, but not limited to: 8.2.6.1. Violation of any term or condition contained in this order; 8.2.6.2. Obtaining this order by misrepresentation, or by failure to disclose fully all relevant facts; 8.2.6.3. A change in any condition or endangerment to human health or environment that requires a temporary or permanent reduction or elimination of the authorized discharge; and, 8.2.6.4. A substantial change in character, location, or volume of the discharge. 8.2.7. Provisions of this permit are severable. If any provision of the permit is found invalid, the remainder of the permit shall not be affected. 8.2.8. After notice and opportunity for hearing, this order may be modified or revoked and reissued for cause, including: 8.2.8.1. Promulgation of a new or revised effluent standard or limitation; 8.2.8.2. A material change in character, location, or volume of the discharge; 8.2.8.3. Access to new information that affects the germs of the permit, including applicable schedules; 8.2.8.4. Correction of technical mistakes or mistaken interpretations of law; and, 8.2.8.5. Other causes set forth under Sub-part D of 40 C.F.R. part 122. 8.2.9. Safeguards shall be provided to ensure maximal compliance with all terms and conditions of this permit. Safeguards shall include preventative and contingency plans and may also include alternative power sources, stand-by generators, retention capacity, operative procedures, or other precautions. Preventative and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-13 contingency plans for controlling and minimizing the effect of accidental discharges shall: 8.2.9.1. Identify possible situations that could cause “upset,” “overflow,” or “bypass,” or other noncompliance. (Loading and storage areas, power outage, waste treatment unit outage, and failure of process equipment, tanks and pipes should be considered). 8.2.9.2. Evaluate the effectiveness of present facilities and procedures and describe procedures and steps to minimize or correct any adverse environmental impact resulting from noncompliance with the permit. 8.2.10. Physical Facilities shall be designed and constructed according to accepted engineering practice and shall be capable of full compliance with this order when properly operated and maintained. Proper operation and maintenance shall be described in an Operation and Maintenance Manual. Facilities shall be accessible during the wet-weather season. 8.2.11. The discharger shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) that are installed or used by the discharger to achieve compliance with the conditions of this order. Electrical and mechanical equipment shall be maintained in accordance with appropriate practices and standards, such as NFPA 70B, Recommended Practice for Electrical Equipment Maintenance; NFPA 70E, Standard for Electrical Safety in the Workplace; ANSI/NETA MTS Standard for Maintenance: Testing Specifications for Electrical Power Equipment and Systems, or procedures established by insurance companies or industry resources. 8.2.12. If the discharger’s facilities are equipped with SCADA or other systems that implement wireless, remote operation, the discharger should implement appropriate safeguards against unauthorized access to the wireless systems. Standards such as NIST SP 800-53, Recommended Security Controls for Federal Information Systems, can provide guidance. 8.2.13. Production and use of reclaimed water is subject to the approval of the Central Coast Water Board. Production and use of reclaimed water shall be in conformance with recycling criteria established in chapter 3, title 22, of the California Administrative Code and chapter 7, division 7, of the Water Code. An engineering report pursuant to section 60323, title 22, of the California Administrative Code is required and a waiver or water recycling requirements from the Central Coast Water Board is required before reclaimed water is supplied for any use, or to any user, not specifically identified and approved either in this Order or another order issued by the Central Coast Water Board. 8.3. Central Coast Standard Provisions – General Monitoring Requirements 8.3.1. If results of monitoring a pollutant appear to violate effluent limitations based on a weekly, monthly, 30-day, or six-month period, but compliance or non-compliance cannot be validated because sampling is too infrequent, the frequency of sampling shall be increased to validate the test within the next monitoring period. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-14 The increased frequency shall be maintained until the Executive Officer agrees the original monitoring frequency may be resumed. For example, if copper is monitored annually and results exceed the six-month median numerical effluent limitation in the permit, monitoring of copper must be increased to a frequency of at least once every two months (Central Coast Standard Provisions – Definitions 1.7.13.). If suspended solids are monitored weekly and results exceed the weekly average numerical limit in the permit, monitoring of suspended solids must be increased to at least four (4) samples every week (Central Coast Standard Provisions – Definitions 1.7.14.). 8.3.2. Water quality analyses performed in order to monitor compliance with this permit shall be by a laboratory certified by the Division of Drinking Water for the constituent(s) being analyzed. Bioassay(s) performed in order to monitor compliance with this permit shall be in accord with guidelines approved by the State Water Board and the California Department of Fish and Wildlife. If the laboratory used or proposed for use by the discharger is not certified by the Division of Drinking Water or, where appropriate, the Department of Fish and Wildlife due to restrictions in the State's laboratory certification program, the discharger shall be considered in compliance with this provision provided: 8.3.2.1. Data results remain consistent with results of samples analyzed by the Central Coast Water Board; 8.3.2.2. A quality assurance program is used at the laboratory, including a manual containing steps followed in this program that is available for inspections by the staff of the Central Coast Water Board; and, 8.3.2.3. Certification is pursued in good faith and obtained as soon as possible after the program is reinstated. 8.3.3. Samples and measurements taken for the purpose of monitoring shall be representative of the monitored activity. Samples shall be taken during periods of peak loading conditions. Influent samples shall be samples collected from the combined flows of all incoming wastes, excluding recycled wastes. Effluent samples shall be samples collected downstream of the last treatment unit and tributary flow and upstream of any mixing with receiving waters. 8.3.4. All monitoring instruments and devices used by the discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. 8.4. Central Coast Standard Provisions – General Reporting Requirements 8.4.1. Reports of marine monitoring surveys conducted to meet receiving water monitoring requirements of the Monitoring and Reporting Program shall include at least the following information: 8.4.1.1. A description of climatic and receiving water characteristics at the time of sampling (weather observations, floating debris, discoloration, wind speed and direction, swell or wave action, time of sampling, tide height, etc.). CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-15 8.4.1.2. A description of sampling stations, including differences unique to each station (e.g., station location, grain size, rocks, shell litter, calcareous worm tubes, evident life, etc.). 8.4.1.3. A description of the sampling procedures and preservation sequence used in the survey. 8.4.1.4. A description of the exact method used for laboratory analysis. In general, analysis shall be conducted according to Central Coast Standard Provisions – 8.3.1 above, and Federal Standard Provision – Monitoring 3.2. However, variations in procedure are acceptable to accommodate the special requirements of sediment analysis. All such variations must be reported with the test results. 8.4.1.5. A brief discussion of the results of the survey. The discussion shall compare data from the control station with data from the outfall stations. All tabulations and computations shall be explained. 8.4.2. Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule shall be submitted within 14 days following each scheduled date unless otherwise specified within the permit. If reporting noncompliance, the report shall include a description of the reason, a description and schedule of tasks necessary to achieve compliance, and an estimated date for achieving full compliance. A second report shall be submitted within 14 days of full compliance. 8.4.3. The Discharger shall file a Report of Waste Discharge or secure a waiver from the Executive Officer at least 180 days before making any material change or proposed change in the character, location, or plume of the discharge. 8.4.4. Within 120 days after the Discharger discovers, or is notified by the Central Coast Water Board, that monthly average daily flow will or may reach design capacity of waste treatment and/or disposal facilities within four (4) years, the Discharger shall file a written report with the Central Coast Water Board. The report shall include: 8.4.4.1. The best estimate of when the monthly average daily dry weather flow rate will equal or exceed design capacity; and, 8.4.4.2. A schedule for studies, design, and other steps needed to provide additional capacity for waste treatment and/or disposal facilities before the waste flow rate equals the capacity of present units. In addition to complying with Federal Standard Provision – Reporting 5.2, the required technical report shall be prepared with public participation and reviewed, approved and jointly submitted by all planning and building departments having jurisdiction in the area served by the waste collection, treatment, or disposal facilities. 8.4.5. All Dischargers shall submit reports electronically to the: California Regional Water Quality Control Board Central Coast Region CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-16 centralcoast@waterboards.ca.gov 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 In addition, Dischargers with designated major discharges shall submit a copy of each document to: Regional Administrator U.S. EPA, Region 9 Attention: CWA Standards and Permits Office (WTR-5) 75 Hawthorne Street San Francisco, California 94105 8.4.6. Transfer of control or ownership of a waste discharge facility must be preceded by a notice to the Central Coast Water Board at least 30 days in advance of the proposed transfer date. The notice must include a written agreement between the existing Discharger and proposed Discharger containing specific date for transfer of responsibility, coverage, and liability between them. Whether a permit may be transferred without modification or revocation and reissuance is at the discretion of the Board. If permit modification or revocation and reissuance is necessary, transfer may be delayed 180 days after the Central Coast Water Board's receipt of a complete permit application. Please also see Federal Standard Provision – Permit Action 2.3. 8.4.7. Except for data determined to be confidential under CWA section 308 (excludes effluent data and permit applications), all reports prepared in accordance with this permit shall be available for public inspection at the office of the Central Coast Water Board or Regional Administrator of U.S. EPA. Please also see Federal Standard Provision – Records 4.3. 8.4.8. By February 1st of each year, the discharger shall submit an annual report to the Central Coast Water Board. The report shall contain the following: 8.4.8.1. Both tabular and graphical summaries of the monitoring data obtained during the previous year. 8.4.8.2. A discussion of the previous year’s compliance record and corrective actions taken, or which may be needed, to bring the discharger into full compliance. 8.4.8.3. An evaluation of wastewater flows with projected flow rate increases over time and the estimated date when flows will reach facility capacity. 8.4.8.4. A discussion of operator certification and a list of current operating personnel and their grades of certification. 8.4.8.5. The date of the facility’s Operation and Maintenance Manual (including contingency plans as described in Provision 8.2.9), the date the manual was last reviewed, and whether the manual is complete and valid for the current facility. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-17 8.4.8.6. A discussion of the laboratories used by the discharger to monitor compliance with effluent limits and a summary of performance relative to section 8.3, General Monitoring Requirements. 8.4.8.7. If the facility treats industrial or domestic wastewater and there is no provision for periodic sludge monitoring in the Monitoring and Reporting Program, the report shall include a summary of sludge quantities, analyses of its chemical and moisture content, and its ultimate destination. 8.4.8.8. If appropriate, the report shall also evaluate the effectiveness of the local source control or pretreatment program using the State Water Board's "Guidelines for Determining the Effectiveness of Local Pretreatment Program." 8.5. Central Coast Standard Provisions – General Pretreatment Provisions 8.5.1. Discharge of pollutants by "indirect dischargers” in specific industrial sub- categories (appendix C, 40 C.F.R. part 403), where categorical pretreatment standards have been established, or are to be established, (according to 40 C.F.R. chapter 1, subchapter N), shall comply with the appropriate pretreatment standards: 8.5.1.1. By the date specified therein; 8.5.1.2. Within three (3) years of the effective date specified therein, but in no case later than July 1, 1984; or, 8.5.1.3. If a new indirect discharger, upon commencement of discharge. 8.6. Central Coast Standard Provision – Enforcement 8.6.1. Any person failing to file a Report of Waste Discharge or other report as required by this permit shall be subject to a civil penalty not to exceed $5,000 per day. 8.6.2. Upon reduction, loss, or failure of the treatment facility, the Discharger shall, to the extent necessary to maintain compliance with this permit, control production or all discharges, or both, until the facility is restored or an alternative method of treatment is provided. 8.7. Central Coast Standard Provisions – Definitions (Not otherwise included in Attachment A to this Order) 8.7.1. A “composite sample" is a combination of no fewer than eight (8) individual samples obtained at equal time intervals (usually hourly) over the specified sampling (composite) period. The volume of each individual sample is proportional to the flow rate at the time of sampling. The period shall be specified in the Monitoring and Reporting Program ordered by the Executive Officer. 8.7.2. “Daily Maximum” limit means the maximum acceptable concentration or mass emission rate of a pollutant measured during a calendar day or during any 24- hour period reasonably representative of the calendar day for purposes of sampling. It is normally compared with results based on "composite samples” except for ammonia, total chlorine, phenolic compounds, and toxicity CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-18 concentration. For all exceptions, comparisons will be made with results from a “grab sample”. 8.7.3. “Discharger", as used herein, means, as appropriate: (1) the Discharger, (2) the local sewering entity (when the collection system is not owned and operated by the Discharger), or (3) "indirect discharger" (where "Discharger" appears in the same paragraph as "indirect discharger”, it refers to the discharger.) 8.7.4. “Duly Authorized Representative" is one where: 8.7.4.1. The authorization is made in writing by a person described in the signatory paragraph of Federal Standard Provision 5.2.; 8.7.4.2. The authorization specifies either an individual or the occupant of a position having either responsibility for the overall operation of the regulated facility, such as the plant manager, or overall responsibility for environmental matters of the company; and, 8.7.4.3. The written authorization was submitted to the Central Coast Water Board. 8.7.5. A "grab sample" is defined as any individual sample collected in less than 15 minutes. "Grab samples” shall be collected during peak loading conditions, which may or may not be during hydraulic peaks. It is used primarily in determining compliance with the daily maximum limits identified in Central Coast Standard Provision – Provision 8.7.2. and instantaneous maximum limits. 8.7.6. "Hazardous substance” means any substance designated under 40 C.F.R. part 116 pursuant to section 311 of the CWA. 8.7.7. "Incompatible wastes” are: 8.7.7.1. Wastes which create a fire or explosion hazard in the treatment works; 8.7.7.2. Wastes which will cause corrosive structural damage to treatment works, but in no case wastes with a pH lower than 5.0 unless the works is specifically designed to accommodate such wastes; 8.7.7.3. Solid or viscous wastes in amounts which cause obstruction to flow in sewers, or which cause other interference with proper operation of treatment works; 8.7.7.4. Any waste, including oxygen demanding pollutants (BOD, etc.), released in such volume or strength as to cause inhibition or disruption in the treatment works and subsequent treatment process upset and loss of treatment efficiency; and, 8.7.7.5. Heat in amounts that inhibit or disrupt biological activity in the treatment works or that raise influent temperatures above 40°C (104°F) unless the treatment works is designed to accommodate such heat. 8.7.8. "Indirect Discharger” means a non-domestic discharger introducing pollutants into a publicly owned treatment and disposal system. 8.7.9. "Log Mean” is the geometric mean. Used for determining compliance of fecal or total coliform populations, it is calculated with the following equation: Log Mean = (C1 x C2 x...x Cn)1/n, CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-19 in which “n" is the number of days samples were analyzed during the period and any "C" is the concentration of bacteria (MPN/100 mL) found on each day of sampling. "n” should be five or more. 8.7.10. “Mass emission rate" is a daily rate defined by the following equations: mass emission rate (lbs/day) = 8.34 x Q x C; and, mass emission rate (kg/day) = 3.79 x Q x C, where “C" (in mg/L) is the measured daily constituent concentration or the average of measured daily constituent concentrations and “Q” (in MGD) is the measured daily flowrate or the average of measured daily flow rates over the period of interest. 8.7.11. The "Maximum Allowable Mass Emission Rate," whether for a month, week, day, or six-month period, is a daily rate determined with the formulas in paragraph 8.7.10, above, using the effluent concentration limit specified in the permit for the period and the average of measured daily flows (up to the allowable flow) over the period. 8.7.12. “Maximum Allowable Six-Month Median Mass Emission Rate" is a daily rate determined with the formulas in Central Coast Standard Provision – Provision 8.7.10, above, using the "six-month Median" effluent limit specified in the permit, and the average of measured daily flows (up to the allowable flow) over a 180-day period. 8.7.13. "Median" is the value below which half the samples (ranked progressively by increasing value) fall. It may be considered the middle value, or the average of two middle values. 8.7.14. "Monthly Average" (or "Weekly Average”, as the case may be) is the arithmetic mean of daily concentrations or of daily mass emission rates over the specified 30-day (or 7-day) period. Average = (X1 + X2 + ... + Xn) / n in which “n" is the number of days samples were analyzed during the period and “X" is either the constituent concentration (mg/l) or mass emission rate (kg/day or lbs/day) for each sampled day. “n" should be four or greater. 8.7.15. "Municipality" means a city, town, borough, county, district, association, or other public body created by or under State law and having jurisdiction over disposal of sewage, industrial waste, or other waste. 8.7.16. "Overflow" means the intentional or unintentional diversion of flow from the collection and transport systems, including pumping facilities. 8.7.17. "Pollutant-free wastewater" means inflow and infiltration, stormwaters, and cooling waters and condensates which are essentially free of pollutants. 8.7.18. "Primary Industry Category" means any industry category listed in 40 C.F.R. part 122, Appendix A. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT D – STANDARD PROVISIONS D-20 8.7.19. "Removal Efficiency" is the ratio of pollutants removed by the treatment unit to pollutants entering the treatment unit. Removal efficiencies of a treatment plant shall be determined using “Monthly averages" of pollutant concentrations (C, in mg/l) of influent and effluent samples collected about the same time and the following equation (or its equivalent): 8.7.20. "Severe property damage" means substantial physical damage to property, damage to treatment facilities which causes them to become inoperable, or substantial and permanent loss to natural resources which can reasonably be expected to occur in the absence of a "bypass”. It does not mean economic loss caused by delays in production. 8.7.21. "Sludge" means the solids, residues, and precipitates separated from, or created in, wastewater by the unit processes of a treatment system. 8.7.22. To "significantly contribute" to a permit violation means an "indirect discharger" must: 8.7.22.1. Discharge a daily pollutant loading in excess of that allowed by contract with the Discharger or by Federal, State, or Local law; 8.7.22.2. Discharge wastewater which substantially differs in nature or constituents from its average discharge; 8.7.22.3. Discharge pollutants, either alone or in conjunction with discharges from other sources, which results in a permit violation or prevents sewage sludge use or disposal; or 8.7.22.4. Discharge pollutants, either alone or in conjunction with pollutants from other sources that increase the magnitude or duration of permit violations. 8.7.23. "Toxic Pollutant" means any pollutant listed as toxic under Section 307 (a) (1) of the CWA or under 40 C.F.R. part 122, Appendix D. Violation of maximum daily discharge limitations are subject to 24-hour reporting (Federal Standard Provisions 5.5.). 8.7.24. “Zone of Initial Dilution" means the region surrounding or adjacent to the end of an outfall pipe or diffuser ports whose boundaries are defined through calculation of a plume model verified by the State Water Board. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-1 E. ATTACHMENT E – MONITORING AND REPORTING PROGRAM TABLE OF CONTENTS 1. GENERAL MONITORING PROVISIONS .................................................................E-2 2. MONITORING LOCATIONS ....................................................................................E-3 3. INFLUENT MONITORING REQUIREMENTS ..........................................................E-5 3.1. Monitoring Location INF-001 .................................................................................E-5 4. EFFLUENT MONITORING REQUIREMENTS .........................................................E-5 4.1. Monitoring Location EFF-001 ................................................................................E-5 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS .................................E-9 5.1. Whole Effluent Acute Toxicity Testing ...................................................................E-9 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable .............. E-18 7. RECYCLING MONITORING REQUIREMENTS .................................................... E-18 7.1. Monitoring Location RCY-001 ............................................................................. E-18 8. RECEIVING WATER MONITORING REQUIREMENTS ........................................ E-19 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW- 006, RSW-007, and RSW-008 .............................................................................. E-19 9. OTHER MONITORING REQUIREMENTS ............................................................. E-21 9.1. Biosolids, Monitoring, and Notification – BIO-001 ............................................... E-21 9.2. Pretreatment Monitoring ...................................................................................... E-26 9.3. Salt and Nutrient Management Plan Reporting ................................................... E-29 9.4. Volumetric Monitoring of Wastewater and Recycled Water ................................. E-30 10. REPORTING REQUIREMENTS .......................................................................... E-30 10.1. General Monitoring and Reporting Requirements ............................................. E-30 10.2. Self-Monitoring Reports (SMRs)........................................................................ E-30 10.3. Discharge Monitoring Reports (DMRs) .............................................................. E-34 10.4. Other Reports .................................................................................................... E-34 TABLE OF TABLES Table E-1. Monitoring Station Locations .......................................................................E-3 Table E-2. Influent Monitoring ......................................................................................E-5 Table E-3. Effluent Monitoring at EFF-001 ...................................................................E-6 Table E-4. Approved Test for Acute Toxicity – Fresh Water ...................................... E-10 Table E-5. Approved Tests for Chronic Toxicity – Freshwater ............................ E-14 Table E-6. Recycled Water Monitoring Requirements at RCY-001 ............................ E-18 Table E-6. Receiving Water Monitoring Requirements............................................... E-19 Table E-8. Amount of Biosolids and Frequency of Analysis ....................................... E-21 Table E-9. Biosolids Monitoring Requirements .......................................................... E-22 Table E-10. Monitoring Periods and Reporting Schedule........................................... E-31 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-2 ATTACHMENT E – MONITORING AND REPORTING PROGRAM Section 308 of the federal Clean Water Act (CWA) and sections 122.41(h), (j)-(l), 122.44(i), and 122.48 of title 40 of the Code of Federal Regulations (40 C.F.R.) require that all NPDES permits specify monitoring and reporting requirements. California Water Code sections 13267 and 13383 also authorize the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) to establish monitoring, inspection, entry, reporting, and recordkeeping requirements. This Monitoring and Reporting Program (MRP) establishes monitoring, reporting, and recordkeeping requirements that implement the federal and California laws and/or regulations. 1. GENERAL MONITORING PROVISIONS 1.1. Laboratories analyzing monitoring samples shall be certified by the State Water Resources Control Board (State Water Board), in accordance with the provision of California Water Code section 13176, and must include quality assurance/quality control data with their reports. 1.2. Samples and measurements taken as required herein shall be representative of the volume and nature of the monitored discharge. All samples shall be taken at the monitoring locations specified in this MRP and, unless otherwise specified, before the monitored flow joins or is diluted by any other waste stream, body of water, or substance. Monitoring locations shall not be changed without notification to and approval of the Central Coast Water Board. 1.3. Appropriate flow measurement devices and methods consistent with accepted scientific practices shall be selected and used to ensure the accuracy and reliability of measurements of the volume of monitored discharges. The devices shall be installed, calibrated, and maintained to ensure that the accuracy of the measurements is consistent with the accepted capability of that type of device. Devices selected shall be capable of measuring flows with a maximum deviation of less than ±10 percent from true discharge rates throughout the range of expected discharge volumes. Guidance in selection, installation, calibration, and operation of acceptable flow measurement devices can be obtained from the following references. 1.3.1. A Guide to Methods and Standards for the Measurement of Water Flow, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 421, May 1975, 96 pp. http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication421.pdf 1.3.2. Water Measurement Manual, U.S. Department of Interior, Bureau of Reclamation, Second Edition, Revised Reprint, 1974, 327 pp. https://www.usbr.gov/tsc/techreferences/mands/wmm/index.htm1.3.3. Flow Measurement in Open Channels and Closed Conduits, U.S. Department of Commerce, National Bureau of Standards, NBS Special Publication 484, October 1977, 982 pp. https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nbsspecialpublication484v2.pdf CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-3 1.3.3. NPDES Compliance Inspection Manual, Chapter 6 – Flow Measurement, U.S. Environmental Protection Agency (U.S. EPA), Office of Water Enforcement, Publication Number 305-K-17-001, January 2017, 918 pp. https://www.epa.gov/compliance/compliance-inspection-manual-national- pollutant-discharge-elimination-system 1.4. All monitoring instruments and devices used by the Discharger to fulfill the prescribed monitoring program shall be properly maintained and calibrated as necessary to ensure their continued accuracy. All flow measurement devices shall be calibrated at least once per year to ensure continued accuracy of the devices. 1.5. Monitoring results, including noncompliance, shall be reported at intervals and in a manner specified in this MRP. 1.6. Unless otherwise specified by this MRP, all monitoring shall be conducted according to test procedures established at 40 C.F.R. part 136, Guidelines Establishing Test Procedures for Analysis of Pollutants. All analyses shall be conducted using the lowest practical quantitation limit achievable using the specified methodology. Where effluent limitations are set below the lowest achievable quantitation limits, pollutants not detected at the lowest practical quantitation limits will be considered in compliance with effluent limitations. Analysis for toxic pollutants listed by the California Toxics Rule shall also adhere to guidance and requirements contained in the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (2005) (SIP). 1.7. The Discharger shall ensure that the results of the Discharge Monitoring Report- Quality Assurance (DMR-QA) Study or the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board at the following address: State Water Resources Control Board; Quality Assurance Program Officer; Office of Information Management and Analysis; 1001 I Street, Sacramento, CA 95814 2. MONITORING LOCATIONS The Discharger shall establish the following monitoring locations to demonstrate compliance with the effluent limitations, discharge specifications, and other requirements in this Order: Table E-1. Monitoring Station Locations Discharge Point Name Monitoring Location Name Monitoring Location Description INF-001 Influent wastewater prior to treatment and following all significant inputs to the collection system of untreated wastewater and inflow and infiltration, where representative samples of CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-4 Discharge Point Name Monitoring Location Name Monitoring Location Description wastewater influent can be obtained prior to any plant return flows or treatment processes EFF-001 EFF-001A At a point where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to entering the discharge pipeline to San Luis Obispo Creek EFF-001B At a point at the end of the discharge pipeline where representative samples of tertiary treated wastewater effluent can be collected after all treatment processes and prior to commingling with other waste streams or being discharged into San Luis Obispo Creek EFF-002 EFF-002 Location where a representative sample of title 22 recycled water can be collected prior to discharge to the recycled water storage tank. Receiving Water RSW-001 At Fox Canyon Road Receiving Water RSW-002 At Mission Receiving Water RSW-003 At Marsh Street Bridge Receiving Water RSW-004 50 feet upstream of effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-005 A location in San Luis Obispo Creek immediately upstream of the confluence with Prefumo Canyon Creek CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-5 Discharge Point Name Monitoring Location Name Monitoring Location Description Receiving Water RSW-006 A location in Prefumo Canyon Creek 50 feet upstream of the confluence with San Luis Obispo Creek Receiving Water RSW-007 Approximately 0.5 miles downstream from effluent structure discharge point on San Luis Obispo Creek Receiving Water RSW-008 At Higuera Street Bridge, near US 101 Biosolids BIO-001 Biosolids at the last point in the biosolids handling process where representative samples of residual solids from the treatment process can be obtained 3. INFLUENT MONITORING REQUIREMENTS 3.1. Monitoring Location INF-001 3.1.1. The Discharger shall monitor influent to the facility at INF-001 as below: Table E-2. Influent Monitoring Parameter Units Sample Type Minimum Sampling Frequency Flow Million gallons per day (MGD) Measured 1/Day Biochemical Oxygen Demand 5-day @ 20°C (BOD5)[2] Milligram per liter (mg/L) 24-hour Composite 1/Month[1] Total Suspended Solids (TSS)[2] mg/L 24-hour Composite 1/Month[1] [1] The Discharger shall report the average and maximum daily flows. [2] Collection of BOD5 and TSS samples shall occur on days that effluent samples are collected. BOD shall be monitored in the influent at the same time as it is monitored in the effluent. 4. EFFLUENT MONITORING REQUIREMENTS 4.1. Monitoring Location EFF-001 4.1.1. The Discharger shall monitor effluent discharged at Monitoring Location EFF-001 as specified in Table E-3. Except where specified, all monitoring will be performed at EFF-001A. If more than one analytical test method is listed for a given CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-6 parameter, the Discharger must select from the listed methods and corresponding Minimum Level: Table E-3. Effluent Monitoring at EFF-001 Parameter Units Sample Type Minimum Sampling Frequency Flow MGD Metered 1/Day Instantaneous Maximum Flow MGD Metered 1/Day Maximum Daily Flow Calculated 1/Month Mean Daily Flow MGD Calculated 1/Month Biochemical Oxygen Demand, 5- day (BOD5) mg/L 24-hour Composite 1/Month BOD Mass Emissions Rate pounds per day (lbs/day) Calculated 1/Month BOD5 Percent removal Calculated 1/Month pH[1] standard units Continuous or Grab 1/Day Chlorine, Total Residual[2] mg/L Continuous or Grab Grab samples shall be taken a minimum of twice per day, and within 30 minutes of any excursion above 0.1 mg/L Chlorine Used[2] lbs/day Calculated 1/Day Temperature[1] °C Continuous or Grab 5/Week Total Coliform MPN/100 mL Grab 5/Week Settleable Solids milliliter per liter (ml/L) Grab 1/Week Ammonia (as N) mg/L Grab 1/Week Un-ionized Ammonia (as N) [1] mg/L Calculated 1/Week Total Suspended Solids (TSS) mg/L 24-hr. composite 1/Week TSS Percent removal Calculated 1/Week Turbidity Nephelo- metric Turbidity 24-hr. composite 1/10 days CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-7 Parameter Units Sample Type Minimum Sampling Frequency Units (NTU) Dissolved Oxygen mg/L Grab 1/Month Color Color units Grab 1/Month Oil and Grease mg/L Grab 1/Month Total Kjeldahl Nitrogen (TKN) (as N) mg/L Grab 1/Month Chlorodibromomethane (aka Dibromochloromethane) μg/L 24-hr. composite 1/Month[3] Chloroform μg/L 24-hr. composite 1/Month Dichlorobromomethane μg/L 24-hr. composite 1/Month[3] Methylene Chloride μg/L 24-hr. composite 1/Month Pentachlorophenol μg/L 24-hr. composite 1/Month Nitrate (as N) mg/L Grab 1/Month Nitrite (as N) mg/L Grab 1/Month Methylene Blue Active Substances (MBAS) mg/L 24-hr. composite 1/Month Molybdenum mg/L Grab 1/Month Dissolved Orthophosphate (as P) mg/L Grab 1/Month Total Phosphate (as P) mg/L Grab 1/Month Total Dissolved Solids (TDS)[2] mg/L Grab 1/Month Sodium mg/L Grab 1/Month Chloride mg/L Grab 1/Month Sulfate mg/L Grab 1/Month Hardness (CaCO3)[4] mg/L 24-hr. composite 1/Quarter Boron mg/L Grab 1/Year (in October) Cobalt mg/L Grab 1/Year (in October) Iron mg/L Grab 1/Year (in October) Lithium mg/L Grab 1/Year (in October) Manganese mg/L Grab 1/Year (in October) Vanadium mg/L Grab 1/Year (in October) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-8 Parameter Units Sample Type Minimum Sampling Frequency Acute Toxicity[5] ”Pass/Fail” and % Effect Grab 1/Year Chronic Toxicity[5] “Pass/Fail and % Effect” Grab 1/Month[6] California Toxics Rule (CTR) Pollutants[7], [8] μg/L 24-Hour composite 1/Year (in October) Title 22 Pollutants[9], [10] μg/L 24-Hour composite 1/Year (in October) [1] Temperature and pH are to be measured at the same time the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] If no exceedances of the effluent limitation occur for a minimum of 12 consecutive months of monitoring then the frequency of monitoring shall be reduced to quarterly. Subsequently, if an exceedance of the effluent limitation occurs during quarterly monitoring, the monitoring frequency shall return to monthly. The Discharger must notify the Central Coast Water Board of the change in monitoring frequency. [4] Hardness monitoring will occur on the same day and time as the California Toxics Rule (CTR) pollutants to allow for conversion from total recoverable to dissolved for hardness dependent metals. [5] Whole effluent acute and chronic toxicity monitoring shall be conducted according to the requirements established in sections 5.1 and 5.2, respectively, of this MRP. [6] Once per year, in October, chronic toxicity monitoring must be performed at EFF- 001B instead of at EFF-001A. [7] The California Toxics Rule (CTR) pollutants are those listed by the CTR at 40 C.F.R. 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). The Discharger shall instruct its analytical laboratory to establish calibration standards so that the Minimum Levels (MLs) presented in Appendix 4 of the SIP are the lowest calibration standards. The Discharger and its analytical laboratory shall select MLs which are below applicable water quality criteria of the CTR; and when applicable water quality criteria are below all MLs, the Discharger and its analytical laboratory shall select the lowest ML. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-9 [8] Monitoring for the CTR pollutants in effluent shall occur simultaneously with monitoring required for the CTR pollutants in receiving water. [9] The title 22 pollutants are those pollutants for which Maximum Contaminant Levels (MCLs) have been established at title 22, division 4, chapter 15, sections 64431 (inorganic chemicals) and 64444 (organic chemicals) of the California Code of Regulations. Where these pollutants are included in other groups of pollutants (CTR Priority Pollutants), monitoring does not need to be duplicated. Analytical methods shall adhere to the Detection Limits for Purposes of Reporting (DLRs) established by title 22 of the California Code of Regulations, division 4, chapter 15, sections 64432 and 64445.1. [10] Monitoring for the title 22 pollutants in effluent shall occur simultaneously with monitoring required for the title 22 pollutants in receiving water. 5. WHOLE EFFLUENT TOXICITY TESTING REQUIREMENTS 5.1. Whole Effluent Acute Toxicity Testing 5.1.1. Routine Acute Toxicity Monitoring Frequency. The Discharger shall conduct at least one acute aquatic toxicity test using the most sensitive species every calendar year during which there is expected to be at least 15 days of discharge in at least one calendar quarter. For the purposes of acute toxicity, the calendar year starts from the initiation of routine monitoring. If the Discharger is unable to sample within the calendar year due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar year was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. 5.1.2. Discharge In-stream Waste Concentration (IWC) for Acute Toxicity. The IWC for this discharge is 100 percent effluent. 5.1.3. Most Sensitive Species. The test species used for acute toxicity testing shall be the most sensitive species. To be consistent with previous Order R3-2014-0033, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct acute toxicity testing from the effective date of this permit until the completion of the required acute species sensitivity screening detailed in section 5.1.6 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation, and the Central Coast Water Board determines that the CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-10 Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.1.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.1.5. Acute Freshwater Species and Test Methods. The Discharger shall conduct acute toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136). Approved tests methods for acute toxicity are listed in Table E-4 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-4. Approved Test for Acute Toxicity – Fresh Water Species Effect Test Duration (hours) Test Method Fathead Minnow (Pimephales promelas) Survival 24, 48, or 96 Survival Test Method 2000.0 Water Flea (Ceriodaphnia dubia) Survival 24, 48, or 96 Survival Test Method 2002.0 5.1.6. Acute Species Sensitivity Screening. The Discharger shall conduct one species sensitivity screening test during the Order’s first required sample collection for acute toxicity. The Discharger shall collect a single effluent sample to initiate and concurrently conduct two toxicity tests using the fish and invertebrate species referenced in Table E-4 above. This sample shall also be analyzed for the parameter(s) required on a monthly and quarterly frequency in Table E-3, during that given month. Samples for the species sensitivity screening shall be analyzed using the TST approach. The species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-11 than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. 5.1.7. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.1.7.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent Effect” for acute toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.80 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.1.7.2. If the effluent toxicity test does not meet all test acceptability criteria (TAC) specified in the referenced test method, Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 2002; Table IA, 40 C.F.R. part 136) then the Discharger must resample and re-test within 7 days. 5.1.7.3. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.1.7.4. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.1.8. Notification. The Discharger shall notify the Central Coast Water Board of an exceedance of the acute toxicity trigger of 90 percent survival as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-12 Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.1.9. Accelerated Monitoring Requirements. If the result of any acute toxicity test fails to meet the single test minimum trigger (70 percent survival), and the testing meets all TAC, the Discharger shall take two more samples, one within 14 days and one within 21 days following receipt of the initial sample result. If any one of the additional samples do not comply with the three-sample median minimum limitation (90 percent survival), the Discharger shall initiate a Toxicity Reduction Evaluation (TRE) in accordance with section 5.4 of the MRP. If the two additional samples are in compliance with the acute toxicity requirement and testing meets all TAC, then a TRE will not be required. 5.1.10. Reporting. The Self-Monitoring Report (SMR) shall include a full laboratory report for each toxicity test (WET report). The WET report shall be prepared using the format and content of section 12 (Report Preparation) of Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms (EPA-821-R-02-012, 5th edition or subsequent editions), including: 5.1.10.1. The toxicity test results in percent (%) survival for the 100 percent effluent sample. 5.1.10.2. The toxicity test results for the TST approach, reported as “Pass” or “Fail” and “Percent Effect” at the acute toxicity IWC for the discharge. 5.1.10.3. Water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.1.10.4. TRE/Toxicity Identification Evaluation (TIE) results. The Executive Officer shall be notified no later than 30 days from completion of each aspect of TRE/TIE analyses. 5.1.10.5. Statistical program (e.g., TST calculator, CETIS, etc.) output results for each toxicity test. 5.2. Chronic Toxicity Monitoring Requirements – Monitoring Location EFF-001 5.2.1. Routine Chronic Toxicity Monitoring Frequency. The Discharger shall conduct at least one chronic aquatic toxicity test every calendar month during which there is expected to be at least 15 days of discharge. Initiation of the routine monitoring test shall be at a time that would allow any required Median Monthly Effluent Limitation (MMEL) compliance tests to be initiated within the same calendar month as the routine monitoring test. For routine chronic toxicity monitoring, the Discharger shall conduct at least one chronic toxicity test using the most sensitive species each calendar month during which there is expected to be at least 15 days of discharge. For the purposes of chronic toxicity, the calendar month starts from the initiation of routine monitoring. The Discharger shall ensure there is sufficient time to perform the MMEL compliance testing within the defined calendar month, should the initial toxicity test result in a “Fail”. If the Discharger is unable to sample within the calendar CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-13 month due to the availability of test organisms, contract laboratory scheduling issues, or some other reason outside of the Discharger’s control, the Discharger shall immediately notify the Central Coast Water Board in writing. If the Central Coast Water Board agrees that the failure to sample within the calendar month was unavoidable, the Central Coast Water Board will specify an alternative sampling window for the monitoring period. The Discharger may request to reduce the monitoring frequency from once per calendar month to once per calendar quarter if all of the following conditions are met: 1) the toxicity requirements in this permit have been followed; and 2) there were no violations of the MMEL or Maximum Daily Effluent Limitation (MDEL) for chronic toxicity within the last five years. If a chronic toxicity test results in a “Fail” at the IWC during reduced monitoring, the frequency is automatically increased back to once per month for a period of five years. 5.2.2. Discharge In-stream Waste Concentration (IWC). The IWC for this discharge is 100 percent effluent. 5.2.3. Most Sensitive Species. The test species used for chronic toxicity testing shall be the most sensitive species. To be consistent with Order No. R3-2014-003, the Discharger shall use the fathead minnow (Pimephales promelas) to conduct chronic toxicity testing from the effective date of this permit until the completion of the required chronic species sensitivity screening described in section 5.2.7 below. If the species sensitivity screening indicates that Pimephales promelas is not the most sensitive species, this permit may be reopened and modified to revise the most sensitive species. Reopening and modification is not required if the species sensitivity screening indicates that Pimephales promelas is the most sensitive species. The Central Coast Water Board may allow the temporary use of the next appropriate species as the most sensitive species when the Discharger submits documentation and the Central Coast Water Board determines that the Discharger has encountered unresolvable test interference or cannot secure a reliable supply of test organisms. The “next appropriate species” is the species exhibiting the highest percent effect at the IWC tested in the last species sensitivity screening other than the most sensitive species. 5.2.4. Sample Volume and Holding Time. The total sample volume shall be determined by the specific toxicity test method used. Sufficient sample volume of the effluent shall be collected to perform the required toxicity test. All toxicity tests shall be conducted as soon as possible following sample collection. No more than 36 hours shall elapse before the conclusion of sample collection and test initiation. 5.2.5. Chronic Freshwater Species and Test Methods. The Discharger shall conduct chronic toxicity tests on effluent samples at the discharge IWC for the discharge in accordance with species and test methods in Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002; Table IA, 40 C.F.R. part 136). Approved CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-14 tests methods for chronic toxicity are listed in Table E-5 below. In no case shall these species be substituted with another test species unless written authorization from the Central Coast Water Board is received. Table E-5. Approved Tests for Chronic Toxicity – Freshwater Species Effect Test Duration (days) Test Method Fathead Minnow (Pimephales promelas) Larval Survival and Growth 7 Larval Survival and Growth Test Method 1000.0 Water Flea (Ceriodaphnia dubia) Survival and Reproduction 6 to 8 days Survival and Reproduction Test Method 1002.0 Green Alga (Selenastrum capricornutum) Growth 4 days Growth Test Method 1003.0 5.2.6. Median Monthly Effluent Limitation (MMEL) Compliance Monitoring. If a chronic toxicity test conducted during routine monitoring results in a “Fail” at the IWC, the Discharger shall conduct a maximum of two chronic toxicity MMEL compliance tests. The MMEL compliance tests shall be initiated within the same calendar month that the first routine chronic toxicity test was initiated that resulted in a “Fail” at the IWC. If the first chronic toxicity MMEL compliance test results in a “Fail” at the IWC, then the second chronic toxicity MMEL compliance test is not required. 5.2.7. Chronic Species Sensitivity Screening. The Discharger shall conduct four species sensitivity screening tests within 18 months of the effective date of this permit and four species sensitivity screening tests within one year of submitting the ROWD for the Facility, with one set of screenings conducted in each quarter for four consecutive quarters. For each set of species sensitivity screenings, the Discharger shall collect a single effluent sample to initiate and concurrently conduct three toxicity tests using the fish, invertebrate, and alga species referenced in Table E-5 above. This sample shall also be analyzed for the parameter(s) required on a monthly and quarterly frequency in Table E-3, during that given month. As allowed under the test method for the Ceriodaphnia dubia and the Pimephales promelas, a second and third sample shall be collected for use as test solution renewal water as the seven-day toxicity test progresses. Samples for the species sensitivity screening shall be analyzed using the TST approach. After the fourth set of species sensitivity screening, the species that exhibits the highest “Percent Effect” at the discharge IWC shall be used for routine monitoring during the permit term. If the percent effect is less than or equal to zero percent effect for each species, or all percent effect values are the same during the species sensitivity screening test, the Discharger shall either use the species that was most sensitive during the previous permit term for routine monitoring or CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-15 repeat the species sensitivity screening for all species to confirm the results of the first screening before selecting the most sensitive species to use for routine monitoring. If two consecutive species sensitivity screening tests demonstrate that the percent effect for all species exhibit less than or equal to zero percent, the Discharger may select the species to be used for routine monitoring during the permit term. During the calendar month, toxicity tests used to determine the most sensitive test species shall be reported as effluent compliance monitoring results for the MDEL and MMEL for chronic toxicity. 5.2.8. Quality Assurance and Additional Requirements. Quality assurance measures, instructions, and other recommendations and requirements are found in the test methods manual referenced above. Additional requirements are specified below. 5.2.8.1. The discharge is subject to determination of “Pass” or “Fail” and “Percent (%) Effect” for chronic toxicity tests using the TST approach described in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R10-003, 2010), Appendix A, Figure A-1, and Table A-1 and Appendix B, Table B-1. The null hypothesis (Ho) for the TST approach is: Mean discharge IWC response ≤ 0.75 × Mean control response. A test result that rejects this null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. This is a t-test (formally Student’s t-test), a statistical analysis comparing two sets of replicate observations in the case of WET, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The relative “Percent Effect” at the discharge IWC is defined and reported as: ((Mean control response - Mean discharge IWC response) ÷ Mean control response) × 100. 5.2.8.2. The MDEL for chronic toxicity is exceeded and a violation will be flagged when a toxicity test during routine monitoring results in “Fail” for the sub-lethal endpoint in accordance with the TST approach and the “Percent Effect” is greater than or equal to 50 percent for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. 5.2.8.3. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests in a calendar month result in a “Fail” in accordance with the TST approach for any endpoint. 5.2.8.4. If the effluent toxicity test does not meet all TAC specified in the referenced test method, Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002) then the Discharger must resample and re-test within 14 days. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-16 5.2.8.5. Dilution water and control water, including brine controls, shall be laboratory water prepared and used as specified in the test methods manual. If dilution water and control water is different from test organism culture water, then a second control using culture water shall also be used. 5.2.8.6. Monthly reference toxicant testing is sufficient if in accordance with Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). All reference toxicant test results should be reviewed and reported using the effects concentration at 25 percent (EC25). 5.2.8.7. The Discharger shall perform toxicity tests on final effluent samples. Chlorine in the final effluent sample may be removed prior to conducting toxicity tests in order to simulate the dechlorination process at the Facility. Ammonia, however, shall not be removed from the effluent sample prior to toxicity testing, unless explicitly authorized under this section of this MRP and the rationale is explained in the Fact Sheet (Attachment F). 5.2.9. Notification. The Discharger shall notify the Central Coast Water Board of a violation of a toxicity MDEL or MMEL as soon as the Discharger learns of the violation, but no later than 24 hours of the Discharger receiving the monitoring results. The notification shall describe actions the Discharger has taken or will take to investigate and correct the cause(s) of toxicity. 5.2.10. Routine Reporting. The SMR shall include a full laboratory report for each chronic toxicity test. This report shall be prepared using the format and content of the test methods manual in section 10 of Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002), Report Preparation, and shall include: 5.2.10.1. The valid toxicity test results for the TST statistical approach, reported as “Pass” or “Fail” and “Percent Effect” at the chronic toxicity IWC for the discharge. All toxicity test results (whether identified as valid or otherwise) conducted during the calendar month shall be reported on the SMR due date specified in Table E-11. 5.2.10.2. Summary water quality measurements for each toxicity test (e.g., pH, dissolved oxygen, temperature, conductivity, hardness, salinity, chlorine, ammonia). 5.2.10.3. The statistical analysis used in National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10- 003, 2010) Appendix A, Figure A-1 and Table A-1, and Appendix B, Table B-1. 5.2.10.4. Statistical program (e.g., TST calculator, CETIS, etc.) output results, including graphical plots, for each toxicity test. 5.2.10.5. Tabular data and graphical plots clearly showing the laboratory’s performance for the reference toxicant for the previous 20 tests and the laboratory’s performance for the control mean, control standard deviation, and control coefficient of variation for the previous 12-month period. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-17 5.2.10.6. Any additional quality assurance/quality control (QA/QC) documentation or any additional chronic toxicity-related information, upon written request from the Central Coast Water Board. 5.3. Accelerated Monitoring Requirements 5.3.1. When acute toxicity is detected in the effluent, or when the chronic toxicity effluent limitation is exceeded during regular toxicity monitoring, and the testing meets all TAC, the Discharger shall initiate accelerated monitoring to confirm the effluent toxicity. 5.3.2. The Discharger shall implement an accelerated monitoring frequency consisting of performing three toxicity tests in a six-week period following the first failed test results. 5.3.3. If implementation of the generic Toxicity Reduction Evaluation (TRE) Work Plan indicates the source of the exceedance of the effluent limitation or toxicity trigger (for instance, a temporary plant upset), then only one additional test is necessary. If exceedance of the effluent limitation or toxicity trigger is detected in this test, the Discharger will continue with accelerated monitoring requirements or implement the Toxicity Identification and Toxicity Reduction Evaluations. 5.3.4. If none of the three tests indicated exceedance of the effluent limitation or toxicity trigger, then the Discharger may return to the normal testing frequency. 5.4. Toxicity Identification Evaluations (TIE) and Toxicity Reduction Evaluation (TRE) Process 5.4.1. A TIE shall be triggered if testing from the accelerated monitoring frequency indicates any of the following: 5.4.1.1. Two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. 5.4.1.2. The TIE shall be initiated within 15 days following failure of the second accelerated monitoring test. 5.4.1.3. If a TIE is triggered prior to the completion of the accelerated testing, the accelerated testing schedule may be terminated, or used as necessary in performing the TIE. 5.4.2. The TIE shall be conducted to identify and evaluate toxicity in accordance with procedures recommended by the U.S. EPA, which include the following: 5.4.2.1. Toxicity Identification Evaluation: Characterization of Chronically Toxic Effluents, Phase I, (U.S. EPA, 1992a); 5.4.2.2. Methods for Aquatic Toxicity Identification Evaluations: Phase I Toxicity Characterization Procedures, Second Edition (U.S. EPA, 1991a); 5.4.2.3. Methods for Aquatic Toxicity Identification Evaluations: Phase II Toxicity Identification Procedures for Sampling Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993a); and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-18 5.4.2.4. Methods for Aquatic Toxicity Identification Evaluations: Phase III Toxicity Confirmation Procedures for Samples Exhibiting Acute and Chronic Toxicity (U.S. EPA, 1993b). 5.4.3. As part of the TIE investigation, the Discharger shall be required to implement its TRE Work Plan. The Discharger shall take all reasonable steps to control toxicity once the source of the toxicity is identified. A failure to conduct required toxicity tests or a TRE within a designated period shall result appropriate enforcement action. Recommended guidance in conducting a TRE includes the following: 5.4.3.1. Toxicity Reduction Evaluation Guidance for Municipal Wastewater Treatment Plants, August 1999, EPA/833B-99/002; and 5.4.3.2. Clarifications Regarding Toxicity Reduction and Identification Evaluations in the National Pollutant Discharge Elimination System Program dated March 27, 2001, U.S. EPA Office of Wastewater Management, Office of Regulatory Enforcement. 5.4.4. The Central Coast Water Board may also require the Discharger conduct a TRE if other information indicates toxicity (e.g., results of additional monitoring, results of monitoring at a higher concentration than the IWC, fish kills, intermittent recurring toxicity), or if there is no effluent available to complete routine monitoring, a MMET test or a MMEL Compliance Test. 6. LAND DISCHARGE MONITORING REQUIREMENTS – Not Applicable 7. RECYCLING MONITORING REQUIREMENTS 7.1. Monitoring Location RCY-001 7.1.1. The Discharger shall monitor recycled water at Monitoring Location RCY-001 as described below: Table E-6. Recycled Water Monitoring Requirements at RCY-001 Parameter Units Sample Type Minimum Sampling Frequency[3] Daily Flow MGD Metered Continuous Total Coliform MPN/100 mL Grab 1/Day Turbidity[1] NTU Metered Continuous pH standard units Grab 1/Day Total Chlorine Residual[2] mg/L Metered Continuous [1] Turbidity to be sampled immediately downstream of the membrane bioreactors. [2] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-19 the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [3] Monitoring is not required during periods recycled water is not being produced for use outside of the Facility. The Discharger shall specify within the SMR if production of recycled water took place during the monitoring period. 7.1.2. In the event the Producer is unable to comply with the conditions of the water recycling requirements and prohibitions, the Producer shall immediately notify the Central Coast Water Board by telephone and submit a written follow-up report with two weeks of the noncompliance. The written report shall include pertinent information explaining reasons for the noncompliance and shall indicate what steps are being taken to prevent the problems from recurring. 7.1.3. An annual self-monitoring report shall be submitted to the Central Coast Water Board by April 1 of the following year. The report shall include the following: 7.1.3.1. A letter transmitting self-monitoring reports shall accompany each report. The letter shall include a discussion of violations found during the reporting period and actions taken or planned for correcting noted violations, such as operation or facility modifications. If the Producer has previously submitted a report describing corrective actions or a time schedule for implementing corrective actions, reference to the previous correspondence will be satisfactory. The transmittal letter shall contain a statement by the Producer or the Producer’s authorized agent, under penalty of perjury, that to the best of the signer’s knowledge the report is true, accurate, and complete. 7.1.3.2. Tabulations of the results of each required analysis by the Producer specified in Table E-6 by date, time, type of sample, and station. 8. RECEIVING WATER MONITORING REQUIREMENTS 8.1. Monitoring Locations RSW-001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW-008 8.1.1. The Discharger shall monitor the receiving water at Monitoring Locations RSW- 001, RSW-002, RSW-003, RSW-004, RSW-005, RSW-006, RSW-007, and RSW- 008 as follows: Table E-7. Receiving Water Monitoring Requirements Parameter Units Sample Type [1] Sampling Station Minimum Sampling Frequency Flow[2] CFS Instantaneous 4, 5, 7, 8 1/Month Flow MGD Estimated 4, 5, 7, 8 1/Month[3] Turbidity[2] NTU Grab 4, 5, 1/Month Color[2] Color units Grab 4, 5 1/Month CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-20 Parameter Units Sample Type [1] Sampling Station Minimum Sampling Frequency pH[2] standard units (s.u.) Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Temperature °C Grab 4, 5 1/Month Un-ionized Ammonia (as N) [4] mg/L Calculated 4, 5 1/Month Nitrate (as N) mg/L Grab 4, 5, 7, 8 1/Month Dissolved Oxygen mg/L Grab 4, 5, 7, 8 1/Month Total Phosphate (as P) mg/L Grab 5, 7, 8 1/Month Algal Description Visual observatio n Grab 5, 7, 8 1/Month Ammonia, Total (as N) mg/L Grab 5, 7, 8 1/Month Total Kjeldahl Nitrogen (as N) mg/L Grab 5, 7, 8 1/Month Total Dissolved Solids (TDS) mg/L Grab 4, 5, 7, 8 1/Month Chloride mg/L Grab 4, 5, 7, 8 1/Month Sulfate mg/L Grab 4, 5, 7, 8 1/Month Sodium mg/L Grab 4, 5, 7, 8 1/Quarter Boron mg/L Grab 4, 5, 7, 8 1/Quarter Hardness, as CaCO3 mg/L Grab 4, 5, 7, 8 1/Quarter Molybdenum mg/L Grab 4, 5, 7, 8 1/Year Methylene Blue Activated Substances mg/L Grab 4, 5, 7, 8 1/Year E. coli MPN/100 mL Grab 4, 5, 7, 8 1/Quarter CTR Pollutants[6], [7] µg/L Grab 4, 5 1/Year Title 22 Pollutants[8], [9] µg/L Grab 4, 5 1/Year [1] Samples shall be obtained only when safe to do so. [2] The San Luis Obispo Creek flow rate shall be used to determine the upstream and downstream stations where these constituents shall be monitored as follows: If the creek flows underground between Monitoring Location RSW-002 and the discharge point, samples shall be obtained from Monitoring Locations RSW-002. If the creek flows aboveground from Monitoring Location RSW-002 to the discharge point, samples shall be obtained from Monitoring Location RSW-004. In eater case, Monitoring Location RSW-005 shall be the downstream location. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-21 [3] Sampling shall be concurrent with sampling of effluent for ammonia. [4] Temperature and pH are to be measured at the same time that the total ammonia sample is collected. Results shall be used to calculate and report un-ionized ammonia concentrations. [5] Narrative description of algae present at the monitoring location shall include: algal color, location with respect to stream banks and depth of water, and appearance (filamentous, matting, attached, etc. percent coverage of water surface). [6] The CTR pollutants are those listed by the CTR at 40 CFR 131.38 (b) (1). These pollutants shall be monitored one time per year. Analyses, compliance determination, and reporting for these pollutants shall adhere to applicable provisions of the Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (SIP). [7] Monitoring of receiving water for the CTR pollutants shall occur simultaneously with effluent monitoring for the CTR pollutants. [8] The title 22 pollutants are those for which primary MCLs have been established and which are listed in sections 64431-A and 64444-A of the California Code of Regulations, title 22, division 4, chapter 15. Where these pollutants are also identified as CTR Priority Pollutants, monitoring does not need to be duplicated. [9] Monitoring of receiving water for the title 22 Pollutants shall occur simultaneously with effluent monitoring for title 22 pollutants. 9. OTHER MONITORING REQUIREMENTS 9.1. Biosolids, Monitoring, and Notification – BIO-001 9.1.1. A representative sample of biosolids shall be obtained from the last point in the handling process (i.e., in the drying beds just prior to removal or from a pond bottom). All constituents shall be analyzed annually for total concentrations for comparison with Total Threshold Limit Concentration (TTLC) criteria. The Waste Extraction Test shall be performed on any constituent when the total concentration of the waste exceeds ten times the Soluble Threshold Limit Concentration (STLC) for that substance. Twelve (12) discrete representative samples shall be collected at separate locations in the biosolids ready for disposal. These 12 samples shall be composited to form one (1) sample for constituent analysis. For accumulated, previously untested biosolids, the Discharger shall develop a representative sampling plan including number and location of sampling points and collect representative samples. The analysis shall test for the metals required in 40 C.F.R. 503.16 (for land application) or 503.26 (for surface disposal), using the methods in Test Methods for Evaluating Solid Waste, Physical/Chemical Methods (U.S. EPA Publication SW-846, all applicable editions and updates), as required in 503.8(b)(4), at the minimum frequencies established therein, provided in the table below. Table E-8. Amount of Biosolids and Frequency of Analysis CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-22 Amount[1] (dry metric tons/365-day period) Minimum Sampling Frequency[2] Greater than zero, but less than 290 Once per year Equal to or greater than 290 but less than 1,500 Once per quarter (four times per year) Equal to or greater than 1,500 but less than 15,000 Once per sixty days (six times per year) Greater than 15,000 Once per month (twelve times per year) [1] For land application, either the amount of bulk biosolids applied to the land or the amount prepared for sale or give-away in a bag or other container for application to the land (dry weight basis). If the Discharger’s biosolids are directly land applied without further treatment by another preparer, biosolids shall also be tested for organic-N, ammonium-N, and nitrate-N at the frequencies required. For surface disposal, the amount of biosolids placed on an active sludge unit (dry weight basis). [2] Test results shall be expressed in mg pollutant per kg biosolids on a 100% dry weight basis. With U.S. EPA approval the amount of biosolids and minimum sampling frequency can coincide with the testing regiment implemented for Cal recycle. Biosolids shall be analyzed for the constituents in the table below. Table E-9. Biosolids Monitoring Requirements Parameter Units Sample Type Minimum Sampling Frequency Quantity Removed Tons or yd3 Measured During Removal Location of Reuse/Disposal General Public or Specific Site -- -- Moisture Content Percent Grab Per Table E-8 (above) pH standard units Grab Per Table E-8 (above) Total Kjeldahl Nitrogen mg/kg[1] Grab Per Table E-8 (above) Ammonia (as N) mg/kg[1] Grab Per Table E-8 (above) Nitrite (as N) mg/kg[1] Grab Per Table E-8 (above) Total Phosphorus mg/kg[1] Grab Per Table E-8 (above) Oil and Grease mg/kg[1] Grab Per Table E-8 (above) Arsenic mg/kg[1] Grab Per Table E-8 (above) Boron mg/kg[1] Grab Per Table E-8 (above) Cadmium mg/kg[1] Grab Per Table E-8 (above) Copper mg/kg[1] Grab Per Table E-8 (above) Chromium (Total) mg/kg[1] Grab Per Table E-8 (above) Lead mg/kg[1] Grab Per Table E-8 (above) Mercury mg/kg[1] Grab Per Table E-8 (above) CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-23 Parameter Units Sample Type Minimum Sampling Frequency Molybdenum mg/kg[1] Grab Per Table E-8 (above) Nickel mg/kg[1] Grab Per Table E-8 (above) Selenium mg/kg[1] Grab Per Table E-8 (above) Zinc mg/kg[1] Grab Per Table E-8 (above) [1] Total sample (including solids and any liquid portion) to be analyzed and results reported as mg/kg based on the dry weight of the sample. 9.1.2. Prior to land application, the Discharger shall demonstrate that the biosolids meet Class A or Class B pathogen reduction levels by one of the methods listed in 40 C.F.R. 503.32 (unless transferred to another preparer who demonstrates pathogen reduction). Prior to disposal in a surface disposal site, the Discharger shall demonstrate that the biosolids meet Class B levels or shall ensure that the site is covered at the end of each operating day. If pathogen reduction is demonstrated using a “Process to Significantly/Further Reduce Pathogens “(PFRP), the Discharger shall maintain daily records of the operating parameters to achieve this reduction. The following applies when biosolids from the Discharger are directly land applied as Class B, without further treatment by a second preparer. If the Discharger demonstrates pathogen reduction by direct testing for fecal coliforms and/or pathogens, samples must be drawn at the frequency in the Amount/Frequency table above. If the Discharger demonstrates Class B pathogen reduction by testing for fecal coliform, at least seven grab samples must be drawn and analyzed during each monitoring event, and a geometric mean calculated from these seven samples. If the Discharger demonstrates Class A pathogen reduction by testing for fecal coliform and/or salmonella, plus one of the PFRP processes or testing for enteric viruses and helminth ova at least four samples of fecal coliform or salmonella must be drawn during each monitoring event. All four samples must meet the limits specified in 503.32(a). 9.1.3. For biosolids that are land applied or placed in a surface disposal site, the Discharger shall track and keep records of the operational parameters used to achieve Vector Attraction Reduction requirements in 40 C.F.R. 503.33(b). 9.1.4. Class 1 facilities (facilities with pretreatment programs or others designated as Class 1 by the Regional Administrator) and federal facilities with greater than five million gallons per day (MGD) influent flow shall sample biosolids for pollutants listed under CWA section 307(a), as required in the pretreatment section of the permit for Publicly Owned Treatment Works (POTWs) with pretreatment programs. Class 1 facilities and federal facilities greater than 5 MGD shall test dioxins/dibenzofurans using a detection limit of less than one pg/g at the time of their next priority pollutant scan if they have not done so within the past five years, and once per five years thereafter. 9.1.5. The biosolids shall be tested annually, or more frequently if necessary, to determine hazardousness. All constituents regulated under title 22 California CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-24 Code or Regulations, division 5, chapter 11, article 3 shall be analyzed for comparison with TTLC criteria. The waste extraction test shall be performed on any constituent when the total concentration of the waste exceeds ten times the STLC limit for that substance. 9.1.6. If biosolids are placed in a surface disposal site (dedicated land disposal site or monofill), a qualified groundwater scientist shall develop a groundwater monitoring program for the site, or shall certify that the placement of biosolids on the site will not contaminate an aquifer. 9.1.7. Biosolids placed in a municipal landfill shall be tested by the Paint Filter Liquids Test (U.S. EPA Method 9095) at the frequency determined by Table E-9, or more often if necessary, to demonstrate that there are no free liquids. 9.1.8. The Discharger, either directly or through contractual agreements with their biosolids management contractors, shall comply with the following notification requirements: 9.1.8.1. Notification of non-compliance. The Discharger shall notify U.S. EPA Region 9, the State Water Board, and the Regional Water Board located in the region where the biosolids are used or disposed, of any non-compliance within 24 hours if the noncompliance may seriously endanger health or the environment. For other instances of non-compliance, the Discharger shall notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance in writing within five working days of becoming aware of the non-compliance. The Discharger shall require their biosolids management contractors to notify U.S. EPA Region 9 and the affected Regional Water Boards of any non-compliance within the same time frames. 9.1.8.2. If biosolids are shipped to another state or Native American lands, the Discharger must send notice at least 60 days prior to the shipment to the permitting authorities in the receiving state or Native American land (the U.S. EPA Regional Office for that area and the State/Native American authorities). 9.1.8.3. For land application (in cases where Class B biosolids are directly applied without further treatment): Prior to reuse of any biosolids from the Discharger’s facility to a new or previously unreported site, the Discharger shall notify U.S. EPA, the Central Coast Water Board, and any other affected Regional Water Board. The notification shall include description of the crops or vegetation to be grown, proposed loading rates and determination of agronomic rates. If any biosolids within a given monitoring period do not meet 40 C.F.R. 503.13 metals concentrations limits, the Discharger (or its contractor) must pre-notify U.S. EPA, and determine the cumulative metals loading to that site to date, as required in 40 C.F.R. 503.12. The Discharger shall notify the applier of all the applier’s requirements under 40 C.F.R. part 503, including the requirement that the applier certify that the management practices, site restrictions, and any applicable vector attraction reduction requirements have been met. The Discharger shall require the applier to certify at the end of 38 months following CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-25 application of Class B biosolids that the harvesting restrictions in effect for up to 38 months have been met. 9.1.8.4. For surface disposal: Prior to disposal to a new or previously unreported site, the Discharger shall notify U.S. EPA and the Central Coast Water Board. The notice shall include a description and a topographic map of the proposed site, depth to ground water, whether the site is lined or unlined, site operator, site owner, and any State or local permits. The notice shall describe procedures for ensuring public access and grazing restrictions for three years following site closure. The notice shall include a ground water monitoring plan or description of why ground water monitoring is not required. 9.1.9. The Discharger shall submit an annual biosolids report to the U.S. EPA Region 9 Biosolids Coordinator and Central Coast Water Board by February 19th of each year (per U.S. EPA guidance and 40 C.F.R. part 503) for the period covering the previous calendar year. This report shall include: 9.1.9.1. Annual biosolids removed in dry tons and percent solids. 9.1.9.2. If appropriate, a narrative description of biosolids dewatering and other treatment processes, including process parameters, including a schematic diagram showing biosolids handling facilities. For example, if drying beds are used, report depth of application and drying time. If composting is used, report the temperature achieved and duration. 9.1.9.3. A description of disposal methods, including the following information as applicable related to the disposal methods used at the facility. If more than one method is used, include the percentage and tonnage of annual biosolids production disposed by each method. 9.1.9.3.1. For landfill disposal include: 1) the Regional Water Board waste discharge requirement (WDR) numbers that regulate the landfills used, 2) the present classifications of the landfills used, 3) the results of any ground water monitoring, 4) certifications of management practices, and 5) the names and locations of the facilities receiving biosolids. 9.1.9.3.2. For land application include: 1) the location of the site(s), 2) the Regional Water Board's WDR numbers that regulate the site(s), 3) the application rate in lbs/acre/year (specify wet or dry), 4) certifications of management practices and site restrictions, and 5) subsequent uses of the land. 9.1.9.3.3. For offsite application by a licensed hauler and composter include: 1) the name, address and U.S. EPA license number of the hauler and composter. 9.1.9.4. Copies of analytical data required by other agencies (i.e. U.S. EPA or County Health Department) and licensed disposal facilities (i.e. landfill, land application, or composting facility) for the previous year. 9.1.9.5. Descriptions of pathogen reduction methods and vector attraction reduction methods. Including supporting time and temperature data, and certifications, as required in 40 C.F.R. 503.17 and 503.27. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-26 9.1.9.6. Names mailing address, and street addresses of persons who received biosolids for storage, further treatment, disposal in a municipal waste landfill, or for other use or disposal methods not covered above, and amounts delivered to each. 9.1.9.7. For all biosolids used or disposed at the Discharger’s facility, the site and management practice information and certification required in 40 C.F.R. 503.17 and 503.27. 9.1.9.8. For all biosolids temporarily stored, the information required in 40 C.F.R. 503.20 is required to demonstrate temporary storage. 9.1.9.9. Reports shall be submitted in electronically using EPA’s Central Data Exchange website at CDX Home | Central Data Exchange | US EPA (cdx.epa.gov). A PDF copy can be printed and sent to: Executive Officer Central Coast Water Board 895 Aerovista Place, Suite 101 San Luis Obispo, CA 93401-7906 9.2. Pretreatment Monitoring By February 1 of each year, the Discharger shall submit an Annual Report to the State Water Board, Central Coast Water Board, and U.S. EPA describing the Discharger’s pretreatment activities over the previous 12 months. In the event that the Discharger is not in compliance with any pretreatment condition of this Order or resulting from pretreatment audits or compliance inspections, then the Discharger shall also include the reasons for noncompliance and state how and when the Discharger will comply with such conditions and requirements. This report shall contain, but not be limited to, the following information: 9.2.1. A summary of analytical results from representative, flow-proportioned, 24-hour composite sampling of the plant's effluent and sludge as provided in the relevant sections of this MRP. The Discharger shall also provide any influent, effluent, or sludge monitoring data for nonpriority pollutants which the Discharger believes may be causing or contributing to interference, pass-through, or adversely impacting sludge quality. Sampling and analysis shall be performed in accordance with the techniques prescribed in 40 C.F.R. part 136 and amendments thereto. 9.2.2. A discussion of upset, interference, or pass-through incidents, if any, at the POTW, which the Discharger knows or suspects were caused by industrial users of the POTW system. The discussion shall include the reasons why incidents occurred, corrective actions taken and, if known, the name and address of the industrial user(s), responsible. Discussions shall also include a review of applicable pollutant limitations to determine whether any additional limitations or changes to existing requirements may be necessary to prevent pass-through, interference, or noncompliance with sludge disposal requirements. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-27 9.2.3. The cumulative number of industrial users that the Discharger has notified regarding Baseline Monitoring Reports and the cumulative number of industrial user responses. 9.2.4. An updated list of the Discharger's industrial users, including their names and addresses, or a list of deletions and additions keyed to a previously submitted list. The Discharger shall provide a brief explanation for each deletion. The list shall identify the industrial users subject to Federal Categorical Standards by specifying which set(s) of standards are applicable. The list shall indicate which categorical industries, or specific pollutants from each industry, are subject to local limitations that are more stringent than the Federal Categorical Standards. The Discharger shall also list the non-categorical industrial users that are subject only to local discharge limitations. The Discharger shall characterize the compliance status of each industrial user by employing the following descriptions. 9.2.4.1. In compliance with Baseline Monitoring Report requirements (where applicable); 9.2.4.2. Consistently achieving compliance; 9.2.4.3. Inconsistently achieving compliance; 9.2.4.4. Significantly violated applicable pretreatment requirements defined by 40 C.F.R. 403.8 (f)(2)(vii); 9.2.4.5. On a schedule to achieve compliance (include the date final compliance is required); 9.2.4.6. Not achieving compliance and not on a compliance schedule; or 9.2.4.7. The Discharger does not know the industrial user's compliance status. A report describing the compliance status of any industrial user characterized by descriptions in Items 9.2.4.4.3. through 9.2.4.4.7., above, shall be submitted quarterly from the annual report date to the State Water Board, Central Coast Water Board, and U.S. EPA. The report shall identify the specific compliance status of each such industrial user. This quarterly reporting requirement shall commence upon issuance of this Order. Quarterly reports shall be submitted May 1, August 1, and November 1. The fourth quarter report shall be incorporated in the Annual Report (February 1). Quarterly reports shall briefly describe POTW compliance with audit/pretreatment compliance inspection requirements. If none of the aforementioned conditions exist, at a minimum, a letter indicating that all industries are in compliance and no violations or changes to the pretreatment program have occurred during the quarter must be submitted. 9.2.4.8. A summary of inspection and sampling activities conducted by the Discharger during the past year to gather information and data regarding industrial users. The summary shall include the following: 9.2.4.8.1. Names and addresses of the industrial users subject to surveillance by the Discharger and an explanation of whether they were inspected, sampled, or both and the frequency of these activities at each user; and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-28 9.2.4.8.2. Conclusions or results from the inspection or sampling of each industrial user. 9.2.4.9. A summary of compliance and enforcement activities during the past year. The summary shall include names and addresses of the industrial users affected by the following actions. 9.2.4.9.1. Warning letters or notices of violation regarding the industrial users' apparent noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the apparent violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.2. Administrative Orders regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.3. Civil actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned the Federal Categorical Standards or local discharge limitations; 9.2.4.9.4. Criminal actions regarding the industrial users' noncompliance with Federal Categorical Standards or local discharge limitations. For each industrial user, identify whether the violation concerned Federal Categorical Standards or local discharge limitations; 9.2.4.9.5. Assessment of monetary penalties. For each industrial user, identify the amount of the penalties; 9.2.4.9.6. Restriction of flow to the POTW; and 9.2.4.9.7. Disconnection from discharge to the POTW. 9.2.4.10. Description of any significant changes in operating the pretreatment program, which differ from the information in the Discharger's approved POTW Pretreatment Program including, but not limited to, changes concerning: 9.2.4.10.1. The program's administrative structure; 9.2.4.10.2. Local industrial discharge limitations; 9.2.4.10.3. Monitoring program and monitoring frequencies; 9.2.4.10.4. Legal authority or enforcement policy; 9.2.4.10.5. Funding mechanisms; 9.2.4.10.6. Resource requirements; and 9.2.4.10.7. Staffing levels. 9.2.4.11. A summary of the annual pretreatment budget, including costs of pretreatment program functions and equipment purchases. 9.2.4.12. A summary of public participation activities to involve and inform the public. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-29 9.2.4.13. A description of any changes in sludge disposal methods and a discussion of any concerns not described elsewhere in the report. The pretreatment quarterly and annual reports shall be signed by a principal executive officer, ranking elected official, or other duly authorized employee who is responsible for the overall operation of the Discharger (POTW - 40 C.F.R. section 403.12(m)). The Discharger shall submit signed copies of the reports to the State Water Board and the Regional Water Board electronically through the SMR module of CIWQS. Signed copies of the reports shall also be submitted electronically to U.S. EPA at R9Pretreatment@epa.gov or as instructed otherwise. 9.3. Salt and Nutrient Management Plan Reporting The previous Order required the Discharger to develop and implement an ongoing salts management plan dedicated to minimized the discharge of salts to and attainment of applicable water quality objectives (WQOs) for salts in San Luis Obispo Creek sub- basin of the Estero Bay Drainage Basin. Additionally, the previous order required the Discharger to develop and implement a Nutrient Management Program, with the intent of reducing mass loading of nutrients in treated effluent and attainment of applicable WQOs for nutrients in the same basin. Based on the annual reports supplied by the Discharger, over the previous period of the Order, the Discharger has demonstrated that the effluent has contributed to exceedances of 2019 Basin Plan WQOs for salts. By February 1 of each year, the Discharger shall submit an annual report (separate from the NPDES annual report) describing salt and nutrient reduction efforts. The report shall include, at a minimum: 9.3.1. Salt Component 9.3.1.1. Calculations of annual salt mass discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; 9.3.1.2. Analysis of wastewater evaporation/salt concentration effects; 9.3.1.3. Analysis of groundwater monitoring results for salts constituents and associated trends; 9.3.1.4. Analysis of potential impacts of salt loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.1.5. A summary of existing salt reduction measures; and, 9.3.1.6. Recommendations and time schedules for implementation of any additional salt reduction measures. 9.3.2. Nutrient Component 9.3.2.1. Calculations of annual nitrogen mass (for all identified species) discharged to (influent) and from (effluent) the wastewater treatment or recycling facility with a description of contributing sources; CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-30 9.3.2.2. Analysis of wastewater treatment facility ability to facilitate nitrification and denitrification, or other means of nitrogen removal; 9.3.2.3. Analysis of groundwater monitoring results for nitrogen constituents and trends; 9.3.2.4. Analysis of potential impacts of nitrogen loading on the groundwater basin (focusing on the relationship between salt concentration in the discharge and the Basin Plan water quality objectives); 9.3.2.5. A summary of existing nitrogen loading reduction measures; and, 9.3.2.6. Recommendations and time schedules for implementation of any additional nitrogen loading reduction measures. 9.4. Volumetric Monitoring of Wastewater and Recycled Water 9.4.1. Monthly volume of wastewater collected and treated by the wastewater treatment plant. 9.4.2. Monthly volume of wastewater treated, specifying level of treatment, including treated wastewater discharged. 9.4.3. Monthly volume of treated wastewater discharged, monthly volume of recycled water distributed for reuse, and annual volume of treated wastewater distributed for beneficial use in compliance with California Code of Regulations, title 22 use categories. 9.5 Discharge to Evaporation Ponds 9.5.1. The Discharger shall provide written notification to the Central Coast Water Board when there is any discharge to or from the Facility’s evaporation ponds, which are described in section 2.1 of the Fact Sheet. If the discharge is anticipated, the Discharger shall provide notice within 10 days prior to the anticipated discharge. If the discharge is unanticipated, the Discharger shall provide notice within 24 hours of the time the discharge occurs. Discharge from the evaporation ponds is not permitted in this Order, so standard provision 5.5 applies. The notification must include discharge dates, times, volumes, and reasons for discharge. The notification must be submitted electronically, consistent with standard provision 5.10. 10. REPORTING REQUIREMENTS 10.1. General Monitoring and Reporting Requirements The Discharger shall comply with all Standard Provisions (Attachment D) related to monitoring, reporting, and recordkeeping. 10.2. Self-Monitoring Reports (SMRs) 10.2.1. The Discharger shall electronically submit SMRs using the State Water Board’s California Integrated Water Quality System (CIWQS) Program website (http://www.waterboards.ca.gov/water_issues/programs/ciwqs). The CIWQS CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-31 website will provide additional information for SMR submittal in the event there will be a planned service interruption for electronic submittal. 10.2.2. The Discharger shall report in the SMR the results for all monitoring specified in this MRP under sections 3 through 9. The Discharger shall submit SMRs including the results of all required monitoring using U.S. EPA-approved test methods or other test methods specified in this Order. SMRs are to include all new monitoring results obtained since the last SMR was submitted. If the Discharger monitors any pollutant more frequently than required by this Order, the results of this monitoring shall be included in the calculations and reporting of the data submitted in the SMR. 10.2.3. Monitoring periods and reporting for all required monitoring shall be completed according to the following schedule: Table E-1011. Monitoring Periods and Reporting Schedule SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date NPDES Monitoring Report – Continuous, Daily, Weekly, Monthly MRP Sections 3 (Influent), 4 (Effluent) and 5 (Whole Effluent Toxicity), 9.5 Monthly First day of second calendar month following period of sampling Updated Toxicity Reduction Evaluation Work Plan Permit Section 6.3.2.1.1 Once 90 days following permit NPDES Monitoring Report - Quarterly MRP Sections 4 (Effluent) and 8.1 (Receiving Water) Quarterly May 1st August 1st November 1st February 1st NPDES Monitoring Report – Annually MRP Sections 4 (Effluent) and 8.1 (Receiving Water), 9.5 Annually February 1st Recycled Water Monitoring Report MRP Section 7.1 (Recycled Water Monitoring) Annually April 1st, the year following CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-32 SMR Name Permit Section for Monitoring and Sampling Data Included in Report SMR Submittal Frequency SMR Due Date Recycled Water Volumetric Monitoring MRP Section 9.4 (Volumetric Reporting of Wastewater and Recycled Water) Annually April 30th, the year following sampling Note: This report is submitted using the GeoTracker system, not CIWQS Biosolids Monitoring Report MRP Section 9.1 (Biosolids Monitoring) Annually February 19th, the year following sampling Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Quarterly May 1st August 1st November 1st February 1st Pretreatment Report MRP Section 9.2 (Pretreatment Monitoring) Annually February 1st, the year following sampling Summary Report Attachment D, Standard Provision, 8.4.8 (page D-16) Annually February 15th, the year following Salt and Nutrient Management Plan Annual Report MRP Section 9.3 (Salt and Nutrient Management Plan Reporting) Annually February 1st, the following year Pollutant Minimization Program Annual Permit Section 6.3.3.2 (Pollutant Minimization Program) Annually February 1, the following year Climate Change Implementation Progress Report Permit Section 6.3.6.2 (Climate Change Adaptation Implementation Progress Report) Every five years May 1st, every five years following permit effective date. ROWD Application Permit renewal application Once per permit term 180 days prior to permit expiration date CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-33 10.2.4. Reporting Protocols. The Discharger shall report with each sample result the applicable Reporting Level (RL) and the current Method Detection Limit (MDL), as determined by the procedure in 40 C.F.R. part 136. The Discharger shall report the results of analytical determinations for the presence of chemical constituents in a sample using the following reporting protocols: 10.2.4.1. Sample results greater than or equal to the RL shall be reported as measured by the laboratory (i.e., the measured chemical concentration in the sample). 10.2.4.2. Sample results less than the RL, but greater than or equal to the laboratory’s MDL, shall be reported as “Detected, but Not Quantified,” or DNQ. The estimated chemical concentration of the sample shall also be reported. For the purposes of data collection, the laboratory shall write the estimated chemical concentration next to DNQ. The laboratory may, if such information is available, include numerical estimates of the data quality for the reported result. Numerical estimates of data quality may be percent accuracy (± a percentage of the reported value), numerical ranges (low to high), or any other means considered appropriate by the laboratory. 10.2.4.3. Sample results less than the laboratory’s MDL shall be reported as “Not Detected,” or ND. 10.2.4.4. Dischargers are to instruct laboratories to establish calibration standards so that the ML value (or its equivalent if there is differential treatment of samples relative to calibration standards) is the lowest calibration standard. At no time is the Discharger to use analytical data derived from extrapolation beyond the lowest point of the calibration curve. 10.2.5. Compliance Determination. Compliance with effluent limitations for priority pollutants shall be determined using sample reporting protocols defined above and Attachment A. For purposes of reporting and administrative enforcement by the Central Coast Water Board and State Water Board, the Discharger shall be deemed out of compliance with effluent limitations if the concentration of the priority pollutant in the monitoring sample is greater than the effluent limitation and greater than or equal to the reporting level (RL). 10.2.6. Multiple Sample Data. When determining compliance with an AMEL, AWEL, or MDEL for priority pollutants and more than one sample result is available, the Discharger shall compute the arithmetic mean unless the data set contains one or more reported determinations of “Detected, but Not Quantified” (DNQ) or “Not Detected” (ND). In those cases, the Discharger shall compute the median in place of the arithmetic mean in accordance with the following procedure: 10.2.6.1. The data set shall be ranked from low to high, ranking the reported ND determinations lowest, DNQ determinations next, followed by quantified values (if any). The order of the individual ND or DNQ determinations is unimportant. 10.2.6.2. The median value of the data set shall be determined. If the data set has an odd number of data points, then the median is the middle value. If the data set has an even number of data points, then the median is the average of the two values around the middle unless one or both of the points are ND or DNQ, in CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-34 which case the median value shall be the lower of the two data points where DNQ is lower than a value and ND is lower than DNQ. 10.2.7. The Discharger shall submit SMRs in accordance with the following requirements: 10.2.7.1. The Discharger shall arrange all reported data in a tabular format. The data shall be summarized to clearly illustrate whether the facility is operating in compliance with interim and/or final effluent limitations. The Discharger is not required to duplicate the submittal of data that is entered in a tabular format within CIWQS. When electronic submittal of data is required and CIWQS does not provide for entry into a tabular format within the system, the Discharger shall electronically submit the data in a tabular format as an attachment. 10.2.7.2. The Discharger shall attach a cover letter to the SMR. The information contained in the cover letter shall clearly identify violations of the waste discharge requirements; discuss corrective actions taken or planned; and the proposed time schedule for corrective actions. Identified violations must include a description of the requirement that was violated and a description of the violation. 10.2.7.3. The Discharger shall electronically self-report all violations of the waste- discharge requirements using the CIWQS self-reported violations function. 10.3. Discharge Monitoring Reports (DMRs) 10.3.1. DMRs are U.S. EPA reporting requirements. The Discharger shall electronically certify and submit DMRs together with SMRs using Electronic Self-Monitoring Reports module eSMR 2.5 or any upgraded version. Electronic DMR submittal shall be in addition to electronic SMR submittal. Information about electronic DMR submittal is available at the DMR website at: (http://www.waterboards.ca.gov/water_issues/programs/discharge_monitoring). 10.4. Other Reports 10.4.1. The Discharger shall report the results of any special studies, acute and chronic toxicity testing, TRE/TIE, and PMP, required by Special Provisions – 6.3. The Discharger shall report the progress in satisfaction of compliance schedule dates specified in Special Provisions – 6.3.7. The Discharger shall submit reports with the first monthly SMR scheduled to be submitted on or immediately following the report due date. 10.4.2. The Discharger shall report the volumetric monitoring requirements as specified in Other Monitoring Requirements - 9.4 to the State Water Board by April 30 of each calendar year. The Discharger shall electronically certify and submit this annual report containing the required data via the State Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. Information about the volumetric reporting of wastewater and recycled water and the Recycled Water Policy is available at the Recycled Water Policy Volumetric Annual Reporting website at http://www.waterboards.ca.gov/recycledwaterpolicy. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT E – MONITORING AND REPORTING PROGRAM E-35 10.4.3. Every five years, the Discharger shall submit a Climate Change Implementation Progress Report as specified in section 6.3.6.2 of this Order. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-1 F. ATTACHMENT F – FACT SHEET TABLE OF CONTENTS 1. PERMIT INFORMATION .......................................................................................... F-3 2. FACILITY DESCRIPTION ........................................................................................ F-5 2.1. Description of Wastewater and Biosolids Treatment and Controls ........................ F-5 2.2. Discharge Points and Receiving Waters ............................................................... F-6 2.3. Summary of Existing Requirements and Self Monitoring Report Data .................. F-6 2.4. Summary of Interim Effluent Limits and Time Schedule Orders ............................ F-8 2.5. Compliance Summary ........................................................................................... F-9 2.6. Planned Changes ................................................................................................ F-10 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS ...................................... F-10 3.1. Legal Authorities.................................................................................................. F-11 3.2. California Environmental Quality Act (CEQA) ..................................................... F-11 3.3. State and Federal Laws, Regulations, Policies, and Plans ................................. F-11 3.4. Impaired Waterbodies on the CWA section 303(d) List ....................................... F-15 3.5. Other Plans, Polices and Regulations ................................................................. F-15 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS ................................................................................................................................... F-17 4.1. Discharge Prohibitions ........................................................................................ F-17 4.2. Technology-Based Effluent Limitations ............................................................... F-18 4.3. Water Quality-Based Effluent Limitations (WQBELs) .......................................... F-20 4.4. Final Effluent Limitation Considerations .............................................................. F-42 4.5. Interim Effluent Limitations – Not Applicable ....................................................... F-47 4.6. Land Discharge Specifications – Not Applicable ................................................. F-47 4.7. Recycling Specifications ...................................................................................... F-47 4.8. Point of Compliance for Effluent Limitations ........................................................ F-47 5. RATIONALE FOR RECEIVING WATER LIMITATIONS ........................................ F-48 5.1. Surface Water ..................................................................................................... F-48 6. RATIONALE FOR PROVISIONS ........................................................................... F-48 6.1. Standard Provisions ............................................................................................ F-48 6.2. Special Provisions ............................................................................................... F-48 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS .............. F-52 7.1. Influent Monitoring ............................................................................................... F-53 7.2. Effluent Monitoring .............................................................................................. F-53 7.3. Whole Effluent Toxicity Testing Requirements .................................................... F-53 7.4. Recycled Water Monitoring ................................................................................. F-54 7.5. Receiving Water Monitoring ................................................................................ F-54 7.6. Other Monitoring Requirements .......................................................................... F-55 9. PUBLIC PARTICIPATION ...................................................................................... F-58 9.1. Notification of Interested Persons........................................................................ F-58 9.2. Written Comments ............................................................................................... F-58 9.4. Reconsideration of Waste Discharge Requirements ........................................... F-59 9.5. Information and Copying ..................................................................................... F-59 9.6. Register of Interested Persons ............................................................................ F-60 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-2 9.7. Additional Information .......................................................................................... F-60 TABLE OF TABLES Table F-1. Facility Information ...................................................................................... F-3 Table F-2. Historic Effluent Limitations and Monitoring Data ........................................ F-7 Table F-3. TSO R3-2014-0036 Interim Effluent Limits ................................................. F-9 Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 ...... F-9 Table F-5. Basin Plan Beneficial Uses ....................................................................... F-12 Table F-6. Secondary Treatment Requirements ........................................................ F-19 Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 ................. F-19 Table F-8. Summary of RPA Results ......................................................................... F-23 Table F-9. Summary of Acute and Chronic Toxicity Test Results .............................. F-39 Table F-10. Final Effluent Limitations – Discharge Point EFF-001 ............................. F-44 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-3 ATTACHMENT F – FACT SHEET As described in section 2.2 of this Order, the California Regional Water Quality Control Board, Central Coast Region (Central Coast Water Board) incorporates this Fact Sheet as findings of the Central Coast Water Board supporting the issuance of this Order. This Fact Sheet includes the legal requirements and technical rationale that serve as the basis for the requirements of this Order. This Order has been prepared under a standardized format to accommodate a broad range of discharge requirements for dischargers in California. Only those sections or subsections of this Order that are specifically identified as “not applicable” have been determined not to apply to this Discharger. Sections or subsections of this Order not specifically identified as “not applicable” are applicable to this Discharger. 1. PERMIT INFORMATION The following table summarizes administrative information related to the facility. Table F-1. Facility Information WDID 3 400107001 Discharger City of San Luis Obispo Name of Facility City of San Luis Obispo Water Resource Recovery Facility Facility Address 35 Prado Road San Luis Obispo, CA 93401 San Luis Obispo County Facility Contact, Title and Phone Patrick McGrath, WRRF Supervisor 805-781-7240 Authorized Person to Sign and Submit Reports Patrick McGrath, WRRF Supervisor 805-781-7240 Mailing Address 35 Prado Road, San Luis Obispo, CA 93401 Billing Address 35 Prado Road, San Luis Obispo, CA 93401 Type of Facility Publicly Owned Treatment Works (POTW) Major or Minor Facility Major Threat to Water Quality 2 Complexity A Pretreatment Program Yes CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-4 Recycling Requirements Production: NPDES R3-2024-0001 Distribution and Use: WQ 2016-0068, DDW Water Reclamation Requirements for Recycled Water Facility Permitted Flow 5.4 million gallons per day (MGD) Facility Design Flow 5.4 MGD Watershed Estero Bay Hydrologic Unit Receiving Water San Luis Obispo Creek Receiving Water Type Inland surface water 1.1. The City of San Luis Obispo (hereinafter Discharger or the City) is the owner and operator of the City of San Luis Obispo Water Resource Recovery Facility (hereinafter Facility), a publicly owned treatment works (POTW). For the purposes of this Order, references to the “discharger” or “permittee” in applicable federal and state laws, regulations, plans, or policy are held to be equivalent to references to the Discharger herein. 1.2. The Facility discharges wastewater to San Luis Obispo Creek, a water of the United States. 1.3. When applicable, state law requires dischargers to file a petition with the State Water Resources Control Board (State Water Board), Division of Water Rights and receive approval for any change in the point of discharge, place of use, or purpose of use of treated wastewater that decreases the flow in any portion of a watercourse. The State Water Board retains separate jurisdictional authority to enforce any applicable requirements under California Water Code section 1211. This is not an NPDES permit requirement. 1.4. The Discharger was previously regulated by Order R3-2014-0033 and National Pollutant Discharge Elimination System (NPDES) Permit CA0049224 adopted on September 25, 2014, and effective on December 1, 2014. The Discharger was also regulated by Time Schedule Order R3-2014-0036 and Time Schedule Order R3- 2019-0124. The Discharger filed a Report of Waste Discharge (ROWD) and submitted an application for reissuance of its waste discharge requirements (WDRs) and NPDES permit on May 28, 2019. 1.5. The Discharger was previously regulated by Waste Discharge Requirements and Master Reclamation Requirements Order R3-2003-081, which authorized the production, distribution, and use of recycled water. 1.6. Federal regulations at 40 C.F.R. section 122.46 limit the duration of NPDES permits to a fixed term not to exceed five years. However, pursuant to California Code of Regulations, title 23, section 2235.4, the terms and conditions of an expired permit are automatically continued pending reissuance of the permit if the Discharger complies with all federal NPDES requirements for continuation of expired permits. Because the Discharger met the requirements of California Code of Regulations, title 23, section 2235.4, Order No. R3-2014-0033, NPDES Permit No. CA0049224 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-5 was administratively continued after the original expiration date of November 30, 2019. 2. FACILITY DESCRIPTION 2.1. Description of Wastewater and Biosolids Treatment and Controls The City of San Luis Obispo Resource Recovery Facility is a municipal wastewater collection, treatment, and disposal facility that discharges tertiary treated wastewater to San Luis Obispo Creek. First constructed in 1920 and located at the southwest corner of the City of San Luis Obispo and adjacent to San Luis Obispo Creek, the Facility provides sewerage service to approximately 47,328 municipal and industrial users from the City of San Luis Obispo, California Polytechnic State University, San Luis Obispo, and the San Luis Obispo County Regional Airport. The City also administers an approved pretreatment program that includes seven significant industrial users, as defined in federal regulations. The Discharger currently operates a collection system that is composed of over 148 miles of main line and 9 lift stations. The design flow capacity of the Facility is 5.4 MGD. During storm events, the estimated wet weather influent flow to the facility is 11.1 MGD due to inflow and infiltration into the collection system from aging or broken/cracked pipes. Ongoing capital improvement projects for sewer line replacement, flow metering, and main line repairs will continue to address areas of concern that result in inflow and infiltration into the Facility. The Discharger has been implementing a significant upgrade of the Facility’s biological, disinfection, and biosolids units since 2019. A focus of the facility upgrade was to improve removal of chorine disinfection byproducts (trihalomethanes, or THMs) and nitrate to meet effluent limits of the previous permit. Another focus of the upgrade was to increase the facility’s ability to treat high inflows from wet-weather events. Prior to the most recent upgrades, the facility’s treatment process consisted of an equalization basin, mechanical screening, grit removal, primary settling, biofiltration, secondary settling, nitrification with two activated sludge aeration basins, final settling, cooling using evaporative cooling towers, dual media filtration, and chlorination/dechlorination. During the upgrade, the discharger removed or abandoned the following components of the facility: bio filter and secondary clarifier, final clarifiers, tertiary dual media filtration, and chlorine disinfection and dechlorination. The two activated sludge basins were converted to Modified Ludzack-Ettinger (MLE) bioreactors for nutrient removal, the dissolved air floatation thickener (DAFT) was modified into a sludge blend tank, and a digester was modified into an odor control unit. The final upgraded treatment system currently consists of mechanical screening with washer compactor, aerated grit removal, primary settling, four MLE bioreactors, hollowfiber membranes, and UV disinfection. Although chlorination and dechlorination of the effluent and recycled water has been terminated due to the use of UV disinfection, the recycled water sent to the storage tank will be dosed with chlorine to maintain a chlorine residual in the recycled water distribution line per best practices of the distribution system. The Discharger may use sodium hypochlorite (chlorine) for CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-6 maintenance purposes such as membrane cleaning in the MLE unit when hydrogen peroxide and/or citric acid is insufficient. If chlorine is used for membrane cleaning, dechlorination of the effluent with sodium bisulfite may be necessary remove the chlorine residual to protect beneficial uses of San Luis Obispo Creek. Biosolids were previously handled with a dissolved air floatation thickener (DAFT), three anaerobic digesters, a screw press, a belt filter press, and drying beds, with the final product shipped out for composting. The upgraded biosolids handling unit now consists of a sludge blend tank, two rotary screw thickeners, two anaerobic digesters, an odor control unit, a screw press, and a belt filter press, with the final product hauled for composting. There are two lined evaporation ponds located at southwest corner of the Facility property. The Discharger has occasionally diverted wastewater to these ponds when it did not meet effluent limitations, rather than discharging the wastewater to the creek. This Order requires the Discharger to submit a written notification to the Central Coast Water Board when wastewater is sent to these ponds. This Order does not provide regulatory coverage for the discharge of wastewater from these ponds to land or surface water. In recent years with large, prolonged storm events, these ponds have filled with stormwater from overland flow (not from the facility). This Order does not provide coverage of stormwater discharge from these ponds. As discussed further in section 3.5.1 of this Fact Sheet, the Discharger is enrolled in the Industrial General Permit (State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001). The Discharger may incorporate these ponds into their Industrial General Permit enrollment to allow for the discharge of stormwater from the ponds, in compliance with all the requirements of the Industrial General Permit. 2.2. Discharge Points and Receiving Waters Tertiary treated wastewater is discharged from Discharge Point EFF-001 to San Luis Obispo Creek, a water of the United States, at latitude 35.244307° N and longitude -120.680618° W. Sampling location EFF-001 A is located prior to discharge into the effluent pipeline that discharges to San Luis Obispo Creek. Sampling location EFF-001 B is located at the most downstream end of the effluent pipeline that discharges to San Luis Obispo creek. The flowrate in San Luis Obispo Creek varies greatly between the wet and dry seasons. No dilution credit has been granted for this discharge. Tertiary treated wastewater is discharged from Discharge Point EFF-002 to the Discharger’s reclaimed water storage tank that is located just south of the UV disinfection system. The reclaimed water storage tank feeds the Discharger’s reclaimed water distribution lines located throughout the city. 2.3. Summary of Existing Requirements and Self Monitoring Report Data Effluent limitations contained in Order R3-2014-0033 for discharges from Discharge Point 001 (Monitoring Location EFF-001) and representative monitoring data from December 1, 2014, to December 1, 2022, are shown in Table F-2: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-7 Table F-2. Historic Effluent Limitations and Monitoring Data Parameter Units Averag e Monthl y Effluen t Limit Averag e Weekly Effluen t Limit Maximum Daily Effluent Limit Highest Average Monthly Discharge Reported Highest Average Weekly Discharge Reported Highest Daily Discharge Reported Flow (dry weather) MGD 5.1 --- --- 8.0 --- 12.9[1] Biochemical Oxygen Demand 5- day @ 20°C (BOD5) milligra ms per liter (mg/L) 10 30 50 8.84 14.3 12.6 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) pounds per day (lbs/day ) 425 1275 2125 382 382 382 Biochemical Oxygen Demand 5- day @ 20°C (BOD5) percent removal ≥85 --- --- 91.6 – 100[2] Total Suspended Solids (TSS) mg/L 10 30 75 7.9 11 23.3 Total Suspended Solids (TSS) lbs/day 425 1275 3190 572 842 1556 Total Suspended Solids (TSS) percent removal ≥85 --- --- 97.3-99.7[2] --- --- Oil and Grease mg/L 5 --- 10 8 --- 8 Settleable Solids milliliter per liter per hour (mL/L/h r) 0.1 --- --- <0.1 --- --- pH standar d units 6.5– 8.3[3] 6.5 – 7.88[4] Nitrate, Total (as N) mg/L 10 --- --- 51.7 --- --- Chlorodibro momethane µg/L 0.4 --- 1.0 5 --- 5 Dichlorobro momethane µg/L 0.56 --- 1.0 22 --- 22 N- Nitrosodimet hylamine µg/L 0.0006 9 --- 0.0014 ND --- ND Dissolved Oxygen mg/L 4.0[5] 4.8 CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-8 Chlorine Residual mg/L --- --- ND[6] --- --- 0.76 Chronic Toxicity Toxic Units Chronic (TUc) --- --- 1.0 --- --- 4.0 Fecal or Total Coliform Bacteria Most probabl e number (MPN)/ 100 mL [7] [8] [9] 79, 94[10] 1.8 350 [1] Reported as maximum daily. Flow occurred in February 2017 during a wet weather event. [2] The numbers represent the range of lowest to highest reported values. [3] Applied as an instantaneous minimum and maximum effluent limitation. [4] Representative values contain the lowest instantaneous minimum to the highest instantaneous maximum. [5] Applied as an instantaneous minimum effluent limitation. [6] ND = less than 0.1 mg/L. Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [7] No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30-day period. [8] The median number of fecal coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days for which analyses have been completed. [9] The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [10] Values occurred within a 30-day time period. 2.4. Summary of Interim Effluent Limits and Time Schedule Orders During the permit term for Order R3-2014-0036, the discharger could not immediately achieve compliance with the chlorodibromomethane, dichlorobromomethane, and nitrate effluent limitations. The Central Coast Water Board issued two time schedule orders (TSOs) to set interim effluent limits and compliance timelines: TSO R3-2014- 0036 and TSO R3-2019-0124. TSO R3-2014-0036 set interim limits for the three aforementioned effluent limits with full compliance with effluent limits by November 30, 2019. With the planned upgrades to the Facility’s biological and disinfection units, TSO R3-2019-0124 extended the deadlines to meet the interim effluent limits with a compliance deadline of March 31, 2020, for chlorodibromomethane and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-9 dichlorobromomethane and a compliance deadline of July 31, 2023 for nitrate. Table F- 3 summarizes the interim effluent limits that were established. The interim effluent limitations were established based on the Facility’s performance. When operating under a TSO, if effluent concentrations exceed the final effluent limitation but do not exceed the interim effluent limitation, an effluent violation has not occurred, and mandatory minimum penalties do not apply. If effluent concentrations exceed both the final and interim effluent limitation values, then an effluent violation has occurred, and mandatory minimum penalties do apply. Table F-3. TSO R3-2014-0036 Interim Effluent Limits Constituent Units Average Monthly Maximum Daily Chlorodibromomethane µg/L - 42 Dichlorobromomethane µg/L - 36 Nitrate (as Nitrogen) mg/L 42.6 - 2.5. Compliance Summary 2.5.1 Effluent Compliance Summary The following discussion is a summary of the violations that occurred during the term and administrative extension of Order No. R3-2014-0033. During the time period from December 1, 2014, to May 31, 2023, the Discharger incurred effluent violations related to nitrate, oil and grease, total coliform, chlorine residual, dichlorobromomethane, and chlorodibromomethane. The number of violations, violation type, and reported value range are provided in Table F-4. Table F-4. Compliance Summary from December 1, 2014 through May 31, 2023 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Nitrate (Total as N) December 2016- November 2022 Monthly Average (Mean) Limit 9 43.2-51.7 10 mg/L Oil and Grease March 2017 Monthly Average Limit 1 6 5 mg/L CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-10 Constituent Monitoring Period Violation Type Number of Violations Reported Value Range Permit Limitation Units Total Coliform July 2018- October 2020 30-Day Specific Limit 3 33-1600 23 MPN/ 100m L Total Coliform December 2019- October 2020 Daily Maximum 3 540-1600 240 MPN/ 100m L Residual Chlorine February 2020- December 2022 Daily Maximum 2 0.35-0.75 ND mg/L Dichlorobro momethane April 2020- October 2022 Monthly Average Limit 4 2.5-17.8 0.56 µg/L Dichlorobro momethane April 2020- October 2022 Daily Maximum 4 2.5-17.8 1 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Monthly Average Limit 3 1.2-5 0.40 µg/L Chlorodibro momethane (Dibromochl oromethane) April 2020- October 2022 Daily Maximum 3 1.2-5 1 µg/L 2.6. Planned Changes The Discharger will continue to implement planned upgrades through 2024. The Discharger has not indicated it plans any significant changes to the Facility beyond those during the term of the Order. 3. APPLICABLE PLANS, POLICIES, AND REGULATIONS The requirements contained in this Order are based on the requirements and authorities described in this section. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-11 3.1. Legal Authorities This Order serves as WDRs pursuant to article 4, chapter 4, division 7 of the California Water Code (commencing with section 13260). This Order is also issued pursuant to section 402 of the federal Clean Water Act (CWA), implementing regulations promulgated by the U.S. Environmental Protection Agency (U.S. EPA), and chapter 5.5, division 7 of the California Water Code (commencing with section 13370). It shall serve as an NPDES permit authorizing the Discharger to discharge into waters of the United States at the discharge location described in Table 1, subject to the WDRs in this Order. 3.2. California Environmental Quality Act (CEQA) Under California Water Code section 13389, this action to adopt an NPDES permit for an existing facility is exempt from the California Environmental Quality Act (CEQA) provisions in Public Resources Code, division 13, chapter 3 (commencing with section 21100). With respect to the recycling specifications and groundwater limitations, this action is exempt from the provisions of CEQA pursuant to title 14, California Code of Regulations, section 15301, class 1 exemption for permitting of existing facilities with no expansion of existing use. 3.3. State and Federal Laws, Regulations, Policies, and Plans 3.3.1. Water Quality Control Plan. The Central Coast Water Board adopted the Water Quality Control Plan for the Central Coastal Basin (Basin Plan), which designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for all waters addressed through the plan. Requirements in this Order implement the Basin Plan. In addition, the Basin Plan implements State Water Board Resolution 88-63, which established state policy that all waters, with certain exceptions, should be considered suitable or potentially suitable for municipal or domestic supply. Beneficial uses established by the 2019 Basin Plan for San Luis Obispo Creek (below W. Marsh Street) are presented below: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-12 Table F-5. Basin Plan Beneficial Uses Discharge Point Receiving Water Name Beneficial Use(s) 001 San Luis Obispo Creek (below W. Marsh Street) Existing: Municipal and Domestic Supply (MUN); Agricultural Supply (AGR); Ground Water Recharge (GWR); Water Contact Recreation (REC-1); Non-Contact Water Recreation (REC-2); Wildlife Habitat (WILD); Cold Freshwater Habitat (COLD); Warm Freshwater Habitat (WARM); Migration of Aquatic Organisms (MIGR) Spawning, Reproduction, and/or Early Development (SPWN); Fresh Water Replenishment (FRSH) Commercial and Sport Fishing (COMM). Intermittent: None. Potential: None. Groundwater throughout the Central Coast Region has designated beneficial uses of agricultural water supply, municipal and domestic water supply, and industrial use. Requirements of this Order implement the Basin Plan. 3.3.2. Thermal Plan. The State Water Board adopted the Water Quality Control Plan for Control of Temperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of California (Thermal Plan) January 7, 1971, and amended the plan on September 18, 1975. This plan contains temperature objectives for surface waters. Requirements of this Order implement the Thermal Plan. 3.3.3. Sediment Quality. The State Water Board adopted the Water Quality Control Plan for Enclosed Bays and Estuaries – Part 1, Sediment Quality on September 16, 2008, and it became effective on August 25, 2009. This plan supersedes other narrative sediment quality objectives and establishes new sediment quality objectives and related implementation provisions for specifically defined sediments in most bays and estuaries. Requirements of this Order implement sediment quality objectives of this plan. 3.3.4. National Toxics Rule (NTR) and California Toxics Rule (CTR). U.S. EPA adopted the NTR on December 22, 1992, and later amended it on May 4, 1995, and November 9, 1999. About forty criteria in the NTR apply in California. On May 18, 2000, U.S. EPA adopted the CTR. The CTR promulgated new toxics criteria for California and, in addition, incorporated the previously adopted NTR criteria CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-13 that were applicable in the state. The CTR was amended on February 13, 2001. These rules contain federal water quality criteria for priority pollutants. 3.3.5. State Implementation Policy. On March 2, 2000, the State Water Board adopted Policy for Implementation of Toxics Standards for Inland Surface Waters, Enclosed Bays, and Estuaries of California (State Implementation Policy or SIP). The SIP became effective on April 28, 2000, with respect to the priority pollutant criteria promulgated for California by the U.S. EPA through the NTR and to the priority pollutant objectives established by the Central Coast Water Board in the Basin Plan. The SIP became effective on May 18, 2000, with respect to the priority pollutant criteria promulgated by the U.S. EPA through the CTR. The State Water Board adopted amendments to the SIP on February 24, 2005, that became effective on July 13, 2005. 3.3.6 Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (ISWEBE Plan). The ISWEBE Plan includes several parts and sections that have been adopted by the State Water Board over time. The applicable parts and sections are discussed below. On May 2, 2017, the State Water Board adopted and ISWEBE Plan Part 2: Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. With ISWEBE Plan Part 2’s approval, the State Water Board approved one new narrative and four new numeric mercury water quality objectives to apply to those inland surface waters, enclosed bays, and estuaries of the state that have any of the following beneficial use designations: COMM, CUL, T-SUB, WILD, MAR, RARE, WARM, COLD, EST, or SAL. The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On August 7, 2018, the State Water Board adopted ISWEBE Plan Part 3: Bacteria Provisions and a Water Quality Standards Variance Policy, which establishes water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). The provisions of ISWEBE Plan Part 2 are to be implemented through NPDES permits and WDRs, among other actions the Regional Water Boards may take. On December 1, 2020, the State Water Board adopted the Aquatic Toxicity Provisions, which are incorporated into the ISWEBE Plan. On October 5, 2021, the State Water Board adopted a resolution to confirm that the Aquatic Toxicity Provisions were adopted as state policy for water quality control for all inland surface waters, enclosed bays, estuaries, and coastal lagoons of the state. The provisions were approved by the California Office of Administrative Law on April 25, 2022 and were approved by the U.S. EPA on May 1, 2023. The provisions include statewide numeric water quality objectives for both acute and chronic toxicity and a program of implementation to control toxicity. The provisions provide consistent protection of aquatic life beneficial uses in inland surface waters, enclosed bays, estuaries, and coastal lagoons throughout the state from the effects of known and unknown toxicants. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-14 This Order is consistent with the ISWEBE Plan and includes effluent limitations for mercury, bacteria, and chronic toxicity. 3.3.6. Domestic Water Quality. In compliance with California Water Code section 106.3, it is the policy of the State of California that every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes. This Order promotes that policy by requiring discharges to meet water quality objectives established in the Basin Plan that are based on drinking water maximum contaminant levels and designed to protect human health and ensure that water is safe for domestic use. 3.3.7. Antidegradation Policy. Federal regulation 40 C.F.R. section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal policy. The State Water Board established California’s antidegradation policy in State Water Board Resolution 68-16, Statement of Policy with Respect to Maintaining High Quality of Waters in California. Resolution 68-16 is deemed to incorporate the federal antidegradation policy where the federal policy applies under federal law. Resolution 68-16 requires that existing water quality be maintained unless degradation is justified by specific findings. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The permitted discharge must be consistent with the antidegradation provision of 40 C.F.R. section 131.12 and State Water Board Resolution 68-16. 3.3.8. Anti-Backsliding Requirements. Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. section 122.44(l) restrict backsliding in NPDES permits. These anti-backsliding provisions require that effluent limitations in a reissued permit must be as stringent as those in the previous permit, with some exceptions in which limitations may be relaxed. 3.3.9. Endangered Species Act Requirements. This Order does not authorize any act that results in the taking of a threatened or endangered species or any act that is now prohibited, or becomes prohibited in the future, under either the California Endangered Species Act (Fish and Game Code sections 2050 to 2097) or the Federal Endangered Species Act (16 U.S.C. sections 1531 to 1544). This Order requires compliance with effluent limits, receiving water limits, and other requirements to protect the beneficial uses of waters of the state. The Discharger is responsible for meeting all applicable requirements of the endangered species acts. 3.3.10. Sewage Sludge and Biosolids. This Order does not authorize any act that results in violation of requirements administered by U.S. EPA to implement 40 C.F.R. part 503, Standards for the Use or Disposal of Sewage Sludge. These standards regulate the final use or disposal of sewage sludge that is generated during the treatment of domestic sewage in a municipal wastewater treatment facility. The Discharger is responsible for meeting all applicable requirements of 40 C.F.R. part 503 that are under U.S. EPA’s enforcement authority. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-15 3.4. Impaired Waterbodies on the CWA section 303(d) List CWA section 303(d) requires states to identify and make a list of specific water bodies where water quality standards are not expected to be met after implementation of technology-based effluent limitations on point sources. For all CWA section 303(d) listed water bodies and pollutants, the Central Coast Water Board must develop and implement total maximum daily loads (TMDLs) that specify waste load allocations (WLAs) for point sources and load allocations (LAs) for non- point sources. The U.S. EPA approved the State’s 2020-2022 303(d) list of impaired water bodies on May 11, 2022. The 2020-2022 303(d) list identifies San Luis Obispo Creek, below Osos Street, as impaired for chloride, sodium, benthic community effects, Escherichia coli (E. coli), dissolved oxygen, nitrate, and toxicity. A TMDL for nitrate was adopted for San Luis Obispo Creek below West Marsh Street. Effluent limitations for nitrate in this Permit are based on Central Coast Water Board Resolution R3-2005-0106 (TMDL for nitrate). A TMDL for pathogens was adopted for San Luis Obispo Creek (R3-2004-0142) but the Facility was not identified as a source and was not assigned a wasteload allocation. However, the Discharger is implementing a Wasteload Allocation Attainment Plan (WAAP) to address pathogens from the sources identified in the TMDL. 3.5. Other Plans, Polices and Regulations 3.5.1. State Water Board Order 2014-0057-DWQ, NPDES General Permit CAS000001, Waste Discharge Requirements for Stormwater Associated with Industrial Activities Excluding Construction Activities (Industrial General Permit). The Industrial General Permit, adopted April 1, 2014, amended August 4, 2015, and November 6, 2018, and effective July 1, 2015, is applicable to POTWs with a design capacity greater than 1.0 MGD. The purpose of the Industrial General Order is to regulate stormwater discharges associated with industrial activities. For the control of stormwater discharged from the Facility, the Discharger has enrolled in and is regulated by the Industrial General Permit. 3.5.2. State Water Board Order. 2022-0103-DWQ Statewide General Waste Discharge Requirements for Sanitary Sewer Systems. State Water Board Order No. 2022-0103-DWQ, adopted on December 6, 2022, is applicable to all "federal and state agencies, municipalities, counties, districts, and other public entities that own or operate sanitary sewer systems greater than one mile in length that collect and/or convey untreated or partially treated wastewater to a publicly owned treatment facility in the State of California." The purpose of Water Quality Order 2022-0103-DWQ is to promote the proper and efficient management, operation, and maintenance of sanitary sewer systems and to minimize the occurrences and impacts of sanitary sewer overflows. The Discharger is enrolled in Water Quality Order 2022-0103-DWQ and must comply with its requirements and any requirements in reissuances to Water Quality Order 2022-0103-DWQ. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-16 3.5.3. State Water Board Recycled Water Policy. The State Water Board adopted the Quality Control Policy for Recycled Water (Recycled Water Policy) on December 11, 2018, and it became effective on April 8, 2019. The purpose of the Recycled Water Policy is to encourage the safe use of recycled water in a manner that is protective of public health and the environment. This Order implements the Recycled Water Policy by supporting the production of recycled water and requiring volumetric reporting of wastewater and recycled water to the State Water Board. The Recycled Water Policy calls for the development of regional groundwater basin/sub-basin salt/nutrient management plans. This Order requires the Discharger to continue to commit funding and in-kind resources to facilitate development of a regional groundwater basin/sub-basin salt/nutrient management plan that implements the Recycled Water Policy. 3.5.4 Statewide General Water Reclamation Requirements for Recycled Water Use (State Water Board Order WQ 2016-0068-DDW). State Water Board Order WQ 2016-0068-DDW, adopted on June 7, 2016, is applicable to recycled water projects where recycled water is used or transported for non-potable uses. The distribution and offsite reuse of recycled water produced by the Facility is subject to State Water Board Order WQ 2016-0068-DDW, or other applicable permit, dependent on final use. 3.5.5 Environmental Justice and Advancing Racial Equity. When issuing or reissuing individual waste discharge requirements or waivers of waste discharge requirements that regulate an activity or a facility that may impact a disadvantaged or tribal community, and that includes a time schedule in accordance with subdivision (c) of Section 13263 for achieving an applicable water quality objective, an alternative compliance path that allows time to come into compliance with water quality objectives, or a water quality variance, the Central Coast Water Board shall make a finding on potential environmental justice, tribal impact, and racial equity considerations. (Water Code § 13149.2, effective Jan. 1, 2023). Water Code section 189.7 requires the Central Coast Water Board to conduct outreach in disadvantaged and/or tribal communities when adopting individual waste discharge requirements. In accordance with the Water Boards’ efforts to advance racial equity, the Central Coast Water Board is also committed to developing and implementing policies and programs to advance racial equity and environmental justice so that race can no longer be used to predict life outcomes, and outcomes for all groups are improved. Upon review of readily available information, the Central Coast Water Board finds that this Order regulates a discharge that does not disproportionately impact the water quality of an economically disadvantaged community or a tribal community. Similarly, this Order does not include a time schedule, alternative compliance path, or variance. Therefore, Water Code section 13149.2 does not apply to this permit reissuance. Nevertheless, the Central Coast Water Board has conducted outreach consistent with Water Code section 189.7 by reaching out to surrounding communities and tribal communities about this Order. Additionally, the Board has considered any environmental justice concerns within the Board’s authority, in accordance with the Water Boards’ efforts to advance racial equity. The Order CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-17 requires the Permittee to meet water quality standards to protect public health and the environment, thereby benefiting all persons and communities within the Region. 4. RATIONALE FOR EFFLUENT LIMITATIONS AND DISCHARGE SPECIFICATIONS The CWA requires point source dischargers to control the amount of conventional, non-conventional, and toxic pollutants that are discharged into the waters of the United States. The control of pollutants discharged is established through effluent limitations and other requirements in NPDES permits. There are two principal bases for effluent limitations in the Code of Federal Regulations: 40 C.F.R. section 122.44(a) requires that permits include applicable technology-based limitations and standards, and 40 C.F.R. section 122.44(d) requires that permits include water quality-based effluent limitations to attain and maintain applicable numeric and narrative water quality criteria to protect the beneficial uses of receiving waters. When numeric water quality objectives have not been established, but a discharge has the reasonable potential to cause or contribute to exceedances of water quality standards described at 40 C.F.R. section 122.44 (d), then 1) water quality based effluent limitations (WQBELS) may be established using a calculated water quality criterion derived from a proposed state criterion or an explicit State policy or regulation interpreting its narrative criterion, 2) WQBELs may be established on a case-by-case basis using U.S. EPA criteria guidance published under CWA Section 304 (a), or 3) WQBELs may be established using an indicator parameter for the pollutant of concern. Several specific factors affecting the development of limitations and requirements in this Order are discussed below. 4.1. Discharge Prohibitions 4.1.1. Discharge Prohibition 3.1. (No discharge at a location or in a manner except as described by the Order). The Order authorizes a single, specific point of discharge to surface waters, and the limitations and conditions established by the Order are based on specific information provided by the Discharger and gained by the Central Coast Water Board through site visits, review of monitoring reports, and other information. Discharges to surface waters at locations not contemplated by this Order or discharges of a character not contemplated by this Order are therefore viewed as inconsistent with CWA section 402’s prohibition against discharges of pollutants except in compliance with the CWA’s permit requirements, effluent limitations, and other enumerated provisions. This prohibition is retained from the previous permit. 4.1.2. Discharge Prohibition 3.2. (Discharge of any waste not specifically regulated by this Order is prohibited). Because limitations and conditions of the Order are based on specific information provided by the Discharger and specific wastes described by the Discharger, the limitations and conditions of the Order do not adequately address waste streams not contemplated during drafting of the Order. To prevent the discharge of such waste streams that may be inadequately CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-18 regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.1.3. Discharge Prohibition 3.3. (Overflow, bypass, or overspray of wastewater from the Discharger’s facilities and the subsequent discharge of untreated or partially treated wastewater, except as provided for in Attachment D, Standard Provision 1.7. (Bypass), is prohibited). The discharge of untreated or partially treated wastewater from the Discharger’s collection, treatment, or disposal facilities represents an unauthorized bypass pursuant to 40 C.F.R. section 122.41(m) or an unauthorized discharge that poses a threat to human health and/or aquatic life, and, therefore, is explicitly prohibited by this Order. 4.1.4. Discharge Prohibition 3.4. (Creation of a condition of pollution, contamination, or nuisance, as defined by Section 13050 of the California Water Code, is prohibited). The Basin Plan requires that the disposal of wastewater to waterbodies be accomplished in a manner that safeguards public health and prevents nuisance conditions. 4.1.5. Discharge Prohibition 3.5. (Discharge shall not cause or contribute to adverse impacts to beneficial uses of water or to threatened or endangered species and their habitat). This prohibition is consistent with the requirements of the Basin Plan. 4.1.6. Discharge Prohibition 3.6. (Discharge of radioactive substances is prohibited). This prohibition is consistent with the requirements of the Basin Plan. 4.1.7. Discharge Prohibition 3.7. (Monthly average dry weather effluent flow shall not exceed 5.4 million gallons per day (MGD), aggregated at Discharge Point 001). To prevent the discharge of such waste streams that may be inadequately regulated, the Order prohibits the discharge of any waste that was not described to the Central Coast Water Board during the process of permit reissuance. 4.2. Technology-Based Effluent Limitations 4.2.1. Scope and Authority Section 301(b) of the CWA and implementing U.S. EPA permit regulations at 40 C.F.R. § 122.44 require that permits include conditions meeting applicable technology-based requirements at a minimum, and any more stringent effluent limitations necessary to meet applicable water quality standards. Where the USEPA has not yet developed technology-based standards for a particular industry or a particular pollutant, CWA Section 402 (a) (1) and USEPA regulations at 40 C.F.R. § 125.3 authorize the use of best professional judgment (BPJ) to derive technology-based effluent limitations on a case-by-case basis. When BPJ is used, the permit writer must consider specific factors outlined at 40 C.F.R. § 125.3. Regulations promulgated in 40 C.F.R. § 125.3(a)(1) require technology- based effluent limitations for municipal dischargers to be placed in NPDES permits based on Secondary Treatment Standards or Equivalent to Secondary Treatment Standards. The Federal Water Pollution Control Act Amendments of 1972 (PL 92-500) established the minimum performance requirements for POTWs [defined in section 304(d)(1)]. Section 301(b)(1)(B) of that act requires CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-19 that such treatment works must, as a minimum, meet effluent limitations based on secondary treatment as defined by the U.S. EPA Administrator. Based on this statutory requirement, U.S. EPA developed secondary treatment regulations, which are specified in 40 C.F.R. part 133. These technology-based regulations apply to all municipal wastewater treatment plants and identify the minimum level of effluent quality attainable by secondary treatment in terms of biochemical oxygen demand (BOD5), total suspended solids (TSS), and pH. The discharge authorized by this Order must meet minimum federal technology-based requirements based on Secondary Treatment Standards at 40 C.F.R. part 133, summarized below: Table F-6. Secondary Treatment Requirements Parameter Units 30-Day Average 7-Day Average BOD5 [1] mg/L 30 45 TSS[1] mg/L 30 45 pH standard units 6.0[2] 9.0[3] [1] The 30-day average percent removal shall not be less than 85 percent. [2] Instantaneous minimum value. [3] Instantaneous maximum value. 4.2.2. Applicable Technology-Based Effluent Limitations 40 C.F.R. section122.45(f)(1) requires effluent limitations be expressed in terms of mass, with some exceptions, and 40 C.F.R. section 122.45(f)(2) allows pollutants that are limited in terms of mass to additionally be limited in terms of other units of measurement. This Order includes effluent limitations expressed in terms of mass and concentration. In addition, pursuant to the exceptions to mass limitations provided in 40 C.F.R. section 122.45(f)(1), some effluent limitations are not expressed in terms of mass, such as pH and temperature, as well as when the applicable standards are expressed in terms of concentration and mass limitations are not necessary to protect the beneficial uses of the receiving waters. 4.2.2.1. The following table summarizes technology-based effluent limitations established by this Order at Discharge Point 001. Table F-7. Technology-Based Effluent Limitations – Discharge Point 001 Parameter Units 30-Day Average 7-Day Average Maximum Daily BOD5[1] mg/L 10 30 50 BOD5 lbs/day [2] 450 1,351 2,252 Total Suspended Solids (TSS)[1] mg/L 10 30 75 TSS lbs/day[2] 450 1,351 3,378 [1] The average monthly percent removal of BOD5 and TSS, as measured at Monitoring Location EFF-001, shall not be less than 85 percent. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-20 [2] Mass loading limits were calculated using the following formulas: lbs/day = pollutant concentration (mg/L) * permitted flow (5.4 MGD) * conversion factor (8.34) [3] Instantaneous minimum value. [4] Instantaneous maximum value. 4.2.2.1.1. BOD5 and TSS. BOD and TSS. Federal regulations, 40 C.F.R. part 133, establish the minimum weekly and monthly average level of effluent quality attainable by secondary treatment for BOD5 and TSS. The Central Coast Water Board has determined that tertiary treatment is necessary to protect the beneficial uses of the receiving stream, thus the final effluent limitations for BOD5 and TSS are based on the technical capability of the tertiary process. The secondary and tertiary treatment standards for BOD5 and TSS are indicators of the effectiveness of the treatment processes. The principal design parameter for wastewater treatment plants is the daily BOD5 and TSS loading rates and the corresponding removal rate of the system. In applying 40 C.F.R. part 133 for weekly and monthly average BOD5 and TSS limitations, the application of tertiary treatment processes results in the ability to achieve lower levels for BOD5 and TSS than the secondary standards currently prescribed; the 30-day average BOD5 and TSS limitations are 10 mg/L, the 7-day average BOD5 and TSS limitations are 30 mg/L. These effluent limitations are based on the capability of a tertiary system. In addition to the average weekly and average monthly effluent limitations, daily maximum effluent limitation of 50 mg/L and 75 mg/L for BOD5 and TSS, respectively, are included in the Order to ensure that the treatment works are not organically overloaded and operate in accordance with design capabilities. In addition, 40 C.F.R. § 133.102, in describing the minimum level of effluent quality attainable by secondary treatment, states that the 30-day average percent removal shall not be less than 85 percent. If 85 percent removal of BOD5 and TSS must be achieved by a secondary treatment plant, it must also be achieved by a tertiary (i.e., treatment beyond secondary level) treatment plant. This Order contains a limitation requiring an average of 85 percent removal of BOD5 and TSS over each calendar month. These effluent limitations are carried over from Order R3-2014-0033. 4.3. Water Quality-Based Effluent Limitations (WQBELs) 4.3.1. Scope and Authority CWA section 301(b) and 40 C.F.R. section 122.44(d) require that permits include limitations more stringent than applicable federal technology-based requirements where necessary to achieve applicable water quality standards. Section 122.44(d)(1)(i) of 40 C.F.R. requires that permits include effluent limitations for all pollutants that are or may be discharged at levels that have the reasonable potential to cause or contribute to an exceedance of a water quality standard, including numeric and narrative objectives within a standard. Where reasonable potential has been established for a pollutant, but there is no numeric criterion or objective for the pollutant, WQBELs must be established using: (1) U.S. EPA criteria guidance under CWA section 304(a), supplemented where CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-21 necessary by other relevant information; (2) an indicator parameter for the pollutant of concern; or (3) a calculated numeric water quality criterion, such as a proposed state criterion or policy interpreting the state’s narrative criterion, supplemented with other relevant information, as provided in section 122.44(d)(1)(vi). The process for determining reasonable potential and calculating WQBELs when necessary is intended to protect the designated uses of the receiving water as specified in the Basin Plan and to achieve applicable water quality objectives and criteria that are contained in other state plans and policies, or any applicable water quality criteria contained in the CTR and NTR. 4.3.2. Applicable Beneficial Uses and Water Quality Criteria and Objectives Beneficial uses described by the 2019 Basin Plan for San Luis Obispo Creek and they are presented in section 3.3.1 of this Fact Sheet. Water quality criteria applicable to this receiving water are established by the CTR, the NTR, and by the 2019 Basin Plan. 4.3.3. Determining the Need for WQBELs NPDES regulations at 40 CFR section 122.44(d) require effluent limitations to control all pollutants which are or may be discharged at a level which will cause, have the reasonable potential to cause, or contribute to an excursion above any State water quality standard. The SIP, the statewide policy that became effective on May 22, 2000, establishes procedures to implement water quality criteria from the NTR and CTR and for priority, toxic pollutant objectives established in the Basin Plan. The implementation procedures of the SIP include methods to determine reasonable potential (for pollutants to cause or contribute to excursions above State water quality standards) and to establish numeric effluent limitations, if necessary, for those pollutants which show reasonable potential. The SIP Section 1.3 requires the Central Coast Water Board to use all available valid, relevant, and representative receiving water and effluent data and information to conduct a reasonable potential analysis (RPA). The Central Coast Water Board analyzed the Discharger’s data for priority pollutants and the nature of the discharge to determine if the discharge has reasonable potential to exceed water quality standards. The RPA is based on effluent data retrieved from CIWQS from the period of December 2014 to December 2022. Some freshwater water quality criteria for metals are hardness dependent, i.e., as hardness decreases, the toxicity of certain metals increases, and the applicable water quality criteria become correspondingly more stringent. The Discharger has not specifically collected hardness data for the receiving water. However, the Central Coast Water Board’s Central Coast Ambient Monitoring Program has nearby monitoring stations on San Luis Obispo Creek that has collected this information. The Water Board used 330 mg/L as CaCO3 as a conservative estimate of the receiving water hardness to determine hardness-based criteria. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-22 To conduct the RPA, the Central Coast Water Board identified the maximum observed effluent (MEC) and background (B) concentrations for each priority, toxic pollutant from receiving water and effluent data provided by the Discharger and compared this data to the most stringent applicable water quality criterion (C) for each pollutant from the NTR, CTR, and the 2019 Basin Plan. The Discharger did not collect background data (B) for receiving water. Section 1.3 of the SIP establishes three triggers for a finding of reasonable potential. 4.3.3.1. Trigger 1. If the MEC is greater than C, there is reasonable potential, and an effluent limitation is required. 4.3.3.2. Trigger 2. If B is greater than C, and the pollutant is detected in effluent (MEC > ND), there is reasonable potential, and an effluent limitation is required. 4.3.3.3. Trigger 3. After reviewing other available and relevant information, a permit writer may decide that a WQBEL is required. Such additional information may include, but is not limited to: the facility type, the discharge type, solids loading analyses, lack of dilution, history of compliance problems, potential toxic impact of the discharge, fish tissue residue data, water quality and beneficial uses of the receiving water, CWA 303(d) listing for the pollutant, and the presence of endangered or threatened species or their critical habitat. For mercury in particular, Part 2 of the SIP revised the above methodology as follows, pursuant to State Water Board Resolution 2017-0027, Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California-Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions (Mercury Provisions). 4.3.3.4. Most stringent water quality objective. The RPA is to use a water column concentration from SIP Part 2’s Table 1 based on the receiving water body type and beneficial use(s) to identify the most stringent mercury water quality objective. For San Luis Obispo Creek, the applicable water column concentration is 0.012 ug/L total mercury. This water column concentration is to be used as the “C” value in the RPA for mercury. This change in methodology changes the water quality objective from 0.05 ug/L in the previous orders to 0.012 ug/L in this Order. 4.3.3.5. Maximum Effluent Concentration. Instead of using the highest observed mercury effluent concentration, the MEC is to be determined as an arithmetic mean of all mercury samples during a calendar year. For this RPA, the highest calendar year arithmetic mean based on the revised methodology for mercury in effluent was 0.03 ug/L. The Discharger collects effluent mercury samples on a yearly basis. 4.3.3.6. Maximum ambient background concentration. Instead of using the highest observed mercury concentration in the upstream receiving water (referred to as “B”), the value of B is to be determined as an arithmetic mean of all mercury samples during a calendar year. This Discharger did not sample for and does not have ambient background concentration data for mercury. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-23 4.3.3.7. Determination. A mercury WQBEL is not required unless the MEC is greater than C. However, if B is greater than C and mercury is detected in the effluent, effluent monitoring is required. A mercury WQBEL is required for this discharge because the MEC (i.e., the highest calendar year average concentration with using one half the mercury detection limits when non-detect) was greater than C and there was no B data available. Therefore, according to Part 2 of the SIP, a mercury effluent limitation is required. Annual monitoring for mercury will be retained from the previous Order. The following table summarizes the RPA for each priority, title 22, or Basin Plan pollutant for which data was available from December 2014 through December 2022 and sets forth the basis upon which WQBELs are included in this Order. Table F-8. Summary of RPA Results CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Priority Pollutants 1 Antimony, Total Recoverable µg/L 9 2.5 6 - No Primary MCL 2 Arsenic, Total Recoverable µg/L 9 <2.0 10 - No Primary MCL 3 Beryllium µg/L 9 <0.2 4 - No Primary MCL 4 Cadmium, Total Recoverable µg/L 9 <0.2 3 - No CA Prim. MCL 5a Chromium (III) µg/L 7 7.0 50 - No CA Prim. MCL for Chromium (Total) 5b Chromium (VI) µg/L 8 1.1 11 - No CTR - Chronic 6 Copper, Total Recoverable µg/L 9 24 26 - No CTR - Chronic 7 Lead, Total Recoverable µg/L 8 6.3 15 - No CA Prim. MCL 8 Mercury, Total Recoverable µg/L 9 0.03 0.012 - Yes Mercury Provisions 9 Nickel, Total Recoverable µg/L 9 7.0 100 - No CA Prim. MCL 10 Selenium, Total Recoverable µg/L 9 1.0 5 - No CTR - Chronic CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-24 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 11 Silver, Total Recoverable µg/L 8 <0.25 31.6 - No CTR - Acute 12 Thallium, Total Recoverable µg/L 9 <0.2 1.7 - No CTR 13 Zinc, Total Recoverable µg/L 9 100 330 - No CTR 14 Cyanide, Total (as CN) µg/L 9 <4.0 5.2 - No CTR 15 Asbestos Million Fibers/L 9 <0.2 7 - No CTR 16 2,3,7,8 TCDD µg/L 9 <0.00000 0251 0.00000001 3 - Ud CTR 17 Acrolein µg/L 8 <5.0 320 - No CTR 18 Acrylonitrile µg/L 8 <2.0 0.059 - Ud CTR 19 Benzene µg/L 9 <0.5 1 - No CA Prim. MCL 20 Bromoform µg/L 73 1.1 4.3 - No CTR 21 Carbon Tetrachloride µg/L 9 <0.5 0.25 - Ud CTR 22 Chlorobenzene µg/L 9 <0.5 70 - No CA Prim. MCL 23 Chlorodibromomethane (aka Dibromochloromethane) µg/L 73 5.4 0.401 - Yes CTR 24 Chloroethane µg/L 8 <0.5 No Criteria - Uc No criteria 25 2-Chloroethylvinyl ether µg/L 8 <1.0 No Criteria - Uc No criteria 26 Chloroform µg/L 8 95.7 60 - Yes NAWQC 27 Dichlorobromomethane µg/L 73 24.8 0.56 - Yes CTR 28 1,1-Dichloroethane µg/L 9 <0.5 5 - No Primary MCL 29 1,2-Dichloroethane µg/L 9 <0.5 0.38 - Ud CTR 30 1,1-Dichloroethylene µg/L 9 <0.5 0.057 - No CTR 31 1,2-Dichloropropane µg/L 9 <0.5 0.52 - No CTR 32 1,3-Dichloropropylene µg/L 1 <0.5 0.5 - No CA Prim. MCL 33 Ethylbenzene µg/L 9 <0.5 300 - No CA Prim. MCL 34 Methyl Bromide (aka Bromomethane) µg/L 8 <0.5 48 - No CTR 35 Methyl Chloride (aka chloromethane) µg/L 8 <0.5 No Criteria - Uc No criteria 36 Methylene Chloride µg/L 9 15 4.7 - Yes CTR CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-25 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 37 1,1,2,2-Tetrachloroethane µg/L 9 <0.5 0.17 - Ud CTR Tetrachloroethylene (aka Tetrachloroethene) µg/L 7 <0.5 0.8 - No CTR 39 Toluene µg/L 9 <0.5 150 - No CA Prim. MCL 40 1,2-Trans-Dichloroethylene µg/L 7 <0.005 10 - No CA Prim. MCL 41 1,1,1-Trichloroethane µg/L 9 <0.5 200 - No CA Prim. MCL 42 1,1,2-Trichloroethane µg/L 9 <0.5 0.6 - No CTR 43 Trichloroethylene (aka Trichloroethene) µg/L 7 <0.5 2.7 - No CTR 44 Vinyl Chloride µg/L 9 <0.5 0.5 - No CA Prim. MCL 45 2-Chlorophenol µg/L 8 <2.0 120 - No CTR 46 2,4-Dichlorophenol µg/L 8 <2.0 93 - No CTR 47 2,4-Dimethylphenol µg/L 8 <1.0 540 - No CTR 48 4,6-dinitro-o-resol (aka 2-methyl-4,6- Dinitrophenol aka 4,6-Dinitro-2- methylphenol) µg/L 7 <1.0 13.4 - No CTR 49 2,4-Dinitrophenol µg/L 8 <5.0 70 - No CTR 50 2-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 51 4-Nitrophenol µg/L 8 <1.0 No Criteria - Uc No criteria 52 3-Methyl-4-Chlorophenol (aka P-chloro-m-resol aka 4-Chloro-3- methylphenol) µg/L 8 <1.0 No Criteria - Uc No criteria 53 Pentachlorophenol µg/L 34 2 0.28 - Yes CTR 54 Phenol, Single Compound µg/L 1 <1.0 1 - No BP 55 2,4,6-Trichlorophenol µg/L 8 <1.0 2.1 - No CTR 56 Acenaphthene µg/L 8 <1.0 1200 - No CTR 57 Acenaphthylene µg/L 8 <1.0 No Criteria - Uc No criteria 58 Anthracene µg/L 8 <1.0 9600 - No CTR CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-26 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 59 Benzidine µg/L 8 <1.0 0.00012 - Ud CTR 60 Benzo(a)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 61 Benzo(a)Pyrene µg/L 9 <0.1 0.0044 - Ud CTR 62 Benzo(b)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 63 Benzo(ghi)Perylene µg/L 8 <1.0 No Criteria - Uc No criteria 64 Benzo(k)Fluoranthene µg/L 8 <1.0 0.0044 - Ud CTR 65 Bis(2- Chloroethoxy)Methane µg/L 8 <1.0 No Criteria - Uc No criteria 66 Bis(2-Chloroethyl)Ether µg/L 8 <1.0 0.031 - Ud CTR 67 Bis(2-Chloroisopropyl)Ether µg/L 8 <1.0 1400 - No CTR 68 Bis(2-Ethylhexyl) Phthalate (aka Di(2-ethylhexyl) Phthalate) µg/L 9 <2.0 1.8 - Ud CTR 69 4-Bromophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 70 Butylbenzyl Phthalate µg/L 8 <1.0 3000 - No CTR 71 2-Chloronaphthalene µg/L 8 <1.0 1700 - No CTR 72 4-Chlorophenyl Phenyl Ether µg/L 8 <1.0 No Criteria - Uc No criteria 73 Chrysene µg/L 8 <1.0 0.0044 - Ud CTR 74 Dibenzo(a,h)Anthracene µg/L 8 <1.0 0.0044 - Ud CTR 75 1,2-Dichlorobenzene µg/L 10 <0.5 600 - No CA Prim. MCL 76 1,3-Dichlorobenzene µg/L 9 <0.5 400 - No CTR 77 1,4-Dichlorobenzene µg/L 10 <0.5 5 - No CA Prim. MCL 78 3,3 Dichlorobenzidine µg/L 8 <1.0 0.04 - Ud CTR 79 Diethyl Phthalate µg/L 8 <1.0 23000 - Ud CTR 80 Dimethyl Phthalate µg/L 8 <1.0 313000 - No CTR 81 Di-n-Butyl Phthalate µg/L 8 <1.0 2700 - No CTR 82 2,4-Dinitrotoluene µg/L 8 <1.0 0.11 - Ud CTR 83 2,6-Dinitrotoluene µg/L 8 <1.0 No Criteria - Uc No criteria 84 Di-n-Octyl Phthalate µg/L 8 <1.0 No Criteria - Uc No criteria CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-27 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 85 1,2-Diphenylhydrazine µg/L 8 <1.0 0.04 - Ud CTR 86 Fluoranthene µg/L 8 <1.0 300 - No CTR 87 Fluorene µg/L 8 <1.0 1300 - No CTR 88 Hexachlorobenzene µg/L 8 <1.0 0.00075 - Ud CTR 89 Hexachlorobutadiene µg/L 8 <1.0 0.44 - Ud CTR 90 Hexachlorocyclopentadiene µg/L 8 <1.0 50 - No CA Prim. MCL 91 Hexachloroethane µg/L 8 <1.0 1.9 - No CTR 92 Indeno(1,2,3-cd)Pyrene µg/L 8 <1.0 0.0044 - Ud CTR 93 Isophorone µg/L 8 <1.0 8.4 - No CTR 94 Naphthalene µg/L 8 <1.0 No Criteria - Uc No criteria 95 Nitrobenzene µg/L 8 <1.0 17 - No CTR 96 N-Nitrosodimethylamine µg/L 35 <0.001 0.00069 - No CTR 97 N-Nitrosodi-n-Propylamine µg/L 8 <1.0 0.005 - Ud CTR 98 N-Nitrosodiphenylamine µg/L 8 <1.0 5 - No CTR 99 Phenanthrene µg/L 8 <1.0 No Criteria - Uc No criteria 100 Pyrene µg/L 8 <1.0 960 - No CTR 101 1,2,4-Trichlorobenzene µg/L 9 <0.5 5 - No CA Prim. MCL 102 Aldrin µg/L 9 <0.005 0.00013 - Ud CTR 103 alpha-BHC µg/L 8 <0.005 0.0039 - Ud CTR 104 beta-BHC µg/L 8 <0.005 0.014 - No CTR 105 gamma-BHC µg/L 10 <0.005 0.019 - No CTR 106 delta-BHC µg/L 8 <0.005 No Criteria - Uc No criteria 107 Chlordane µg/L 9 <0.047 0.00057 - Ud CTR 108 4,4'-DDT µg/L 8 <0.005 0.00059 - Ud CTR 109 4,4'-DDE µg/L 8 <0.005 0.00059 - Ud CTR 110 4,4'-DDD µg/L 8 <0.005 0.00083 - Ud CTR 111 Dieldrin µg/L 9 <0.005 0.00014 - Ud CTR 112 alpha-Endosulfan µg/L 8 <0.005 0.056 - No CTR 113 beta-Endolsulfan µg/L 8 <0.005 0.056 - No CTR 114 Endosulfan Sulfate µg/L 8 <0.005 110 - No CTR 115 Endrin µg/L 10 <0.005 0.036 - No CTR CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-28 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] 116 Endrin Aldehyde µg/L 7 <0.005 0.76 - No CTR 117 Heptachlor µg/L 10 <0.005 0.00021 - Ud CTR 118 Heptachlor Epoxide µg/L 10 <0.005 0.00011 - Ud CTR 119- 125 PCBs sum µg/L 2 <0.5 0.00017 - Ud CTR 126 Toxaphene µg/L 9 <0.24 0.0002 - Ud CTR Non-Priority Pollutants Drinking Water Quality Objectives Aluminum µg/L 9 150 200 - No CA Sec. MCL Barium µg/L 9 42.9 1000 - No CA Prim. MCL Fluoride mg/L 9 0.7 1 - No BP Nitrate, Total (as N) mg/L 151 51.7 10 8.1 Yes EPA Prim. MCL Nitrate + Nitrite (as N) mg/L 7 43.4 10 - Yes CA Prim. MCL Nitrite, Total (as N) mg/L 106 5.1 1 <0.1 Yes CA Prim. MCL Methyl-tert-butyl ether µg/L 9 <1.0 5 - No CA Sec. MCL Styrene µg/L 9 <0.5 100 - No CA Prim. MCL Alachlor µg/L 9 <0.1 2 - No CA Prim. MCL Atrazine µg/L 9 <0.1 1 - No CA Prim. MCL Bentazon µg/L 9 <2.0 18 - No CA Prim. MCL Carbofuran µg/L 9 <5.0 18 - No CA Prim. MCL 2,4-D µg/L 9 5 70 - No CA Prim. MCL Dalapon µg/L 9 <10.0 200 - No CA Prim. MCL Dibromochloropropane (aka 1,2-Dibromo-3- Chloropropane) µg/L 8 <0.01 0.2 - No CA Prim. MCL Di(2-ethylhexyl)adipate µg/L 9 <5.0 400 - No CA Prim. MCL Dinoseb µg/L 9 <1.0 7 - No CA Prim. MCL Diquat µg/L 9 <2.0 20 - No CA Prim. MCL Endothall µg/L 9 <40 100 - No CA Prim. MCL Ethylene Dibromide (aka 1,2-Dibromoethane) µg/L 8 <0.02 0.05 - No CA Prim. MCL CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-29 CTR # Parameter Units N[1] MEC[2] Most Stringent Criteria Background RPA Result[3] Basis[4] Glyphosate µg/L 9 <20.0 700 - No CA Prim. MCL Methoxychlor µg/L 10 <0.1 30 - No CA Prim. MCL Molinate µg/L 9 <0.1 20 - No CA Prim. MCL Oxamyl µg/L 9 <5.0 50 - No CA Prim. MCL Picloram µg/L 9 <1.0 500 - No CA Prim. MCL Simazine µg/L 9 <0.1 4 - No CA Prim. MCL Thiobencarb µg/L 9 <0.1 70 - No CA Prim. MCL 2,4,5-TP (Silvex) µg/L 9 <1.0 50 - No CA Prim. MCL Trichlorofluoromethane µg/L 9 <0.5 150 - No CA Prim. MCL 1,1,2-Trichloro-1,2,2- Trifluoroethane µg/L 3 <0.5 1200 - No CA Prim. MCL Xylenes µg/L 9 <0.5 1750 - No CA Prim. MCL Methylene blue activated substances (MBAS) µg/L 8 800 200 - Yes BP Un-ionized Ammonia (as N) mg/L [5] [5] 0.025 - Yes[5] BP Board 3 Basin Plan Water Quality Objectives for Agricultural Water Use Boron, Total µg/L 7 260 750 - No BP Cobalt, Total µg/L 7 4.0 50 - No BP Iron, Total µg/L 8 520 5000 - No BP Lithium, Total µg/L 7 14 2500d - No BP Manganese, Total µg/L 8 42.8 200 - No BP Molybdenum, Total µg/L 7 17 10 - Yes BP Vanadium, Total µg/L 7 5 100 - No BP San Luis Obispo Creek Sub-Area Surface Water Quality Objectives Total Dissolved Solids mg/L 38 990 650 470- 750[6] Yes BP Chloride mg/L 39 209 100 31- 92[6] Yes BP Sulfate, Total, (as SO4) mg/L 6 142 100 - Yes BP Sodium mg/L 35 181 50 29- 72[6] Yes BP [1] Number of data points available for the RPA. [2] If there is a detected value, the highest reported value is summarized in the table. If there are no detected values, if available, the lowest MDL is summarized in the table. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-30 [3] RPA Results: = Yes, if MEC > WQO/WQC, or B > WQO/WQC and MEC is detected; = No, if MEC and B are < WQO/WQC or all effluent data are undetected; = (Uc) Undetermined, if no criteria have been promulgated; = (Ud) Undetermined, for lack of data. As described in section 1.3 in the SIP, if monitoring results show non-detect for all samples of a pollutant and if all reported detection limits of the pollutant in the effluent are greater than or equal to the C value, the RWQCB shall require additional monitoring for the pollutant in place of a water quality-based effluent limitation. For pollutants with a result of Ud, additional monitoring is established through this permit. [4] Basis of Most Stringent Criteria CTR - California Toxics Rule’ CA Prim. MCL - California Primary MCL CA Sec. MCL - California Secondary MCL EPA Prim. MCL - EPA Primary MCL EPA Sec. MCL - EPA Secondary MCL NAWQC - National Ambient Water Quality Criteria BP - Central Coast Regional Board 2019 Basin Plan SWRCB 2017-0027 - Part 2 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California—Tribal and Subsistence Fishing Beneficial Uses and Mercury Provisions. [5] The reasonable potential for the effluent to exceed the 2019 Basin Plan water quality objective for San Luis Obispo Creek for un-ionized ammonia is based on 93 concurrent upstream (RSW-004) and downstream (RSW-005) monitoring data results from December 2014 through April 2020. [6] Range of measured values. The 2019 Basin Plan Water Quality Objective for this pollutant is an annual mean. 4.3.4. WQBEL Calculations As detailed in Table F-6, reasonable potential has been determined for mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, total nitrate (as N), nitrate + nitrite (as N), total nitrite (as N), un- ionized ammonia (as N), methylene blue activated substances (MBAS), total molybdenum, total dissolved solids (TDS), sulfate, sodium, and chloride. The following example demonstrates how WQBELs were established for this Order for chlorodibromomethane. Step 1: For each water quality criterion/objective, an effluent concentration allowance (ECA) is calculated from the following equation to account for dilution and background levels of each pollutant. ECA = C + D (C – B), when C > B, and ECA = C when C ≤ B, Where, C = the applicable water quality criterion (adjusted for receiving water hardness and expressed as total recoverable metal, if applicable). CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-31 D = the dilution credit (here D = 0, as the Central Coast Water Board has no information with which to justify credit for dilution). B = the background concentration As discussed above, for this Order, dilution was not allowed; therefore: ECA = C For chlorodibromomethane, the applicable water quality criteria are: ECAHuman Health = 0.401 μg/L Step 2: For each ECA based on an aquatic life criterion, the long-term average discharge condition (LTA) is determined by multiplying the ECA times a factor (multiplier), which adjusts the ECA to account for effluent variability. The multiplier varies depending on the coefficient of variation (CV) of the data set and whether it is an acute or chronic criterion/objective. Table 1 of the SIP provides pre-calculated values for the multipliers based on the value of the CV. When the data set contains less than 10 sample results, or 80 percent or more of the data are reported as non-detect (ND), the CV is set equal to 0.6. Derivation of the multipliers is presented in Section 1.4 of the SIP. LTAacute = ECAacute x Multiplieracute 99 LTAchronic= ECAchronic x Multiplierchronic 99 Typically, historic effluent data is used to develop the acute and chronic LTA using equations provided in Section 1.4, Step 3 of the SIP (Table 1 of the SIP also provides this data up to three decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the development of this permit and LTA for acute and chronic were unnecessary to calculate. Step 3: WQBELs, including an AMEL and a MDEL are calculated using the most limiting (the lowest) LTA. The LTA is multiplied times a factor that accounts for averaging periods and exceedance frequencies of the effluent limitations, and for the AMEL, the effluent monitoring frequency. Here, the sampling frequency is set equal to 1 (n = 1). The 99th percentile occurrence probability was used to determine the MDEL multiplier and a 95th percentile occurrence probability was used to determine the AMEL multiplier. Table 2 of the SIP presents the MDEL and AMEL multipliers as a function of the CV. When the data set contains less than 10 sample results, or when 80 percent or more of the data set is reported as non-detect (ND), the CV is set equal to 0.6. Otherwise, the CV is calculated as the standard deviation divided by the mean. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-32 No. of Samples No. of Samples Per Month (n) CV 73 1 0.6 Step 4: Calculate the WQBELs by multiplying the LTA by a factor (multiplier). WQBELs are expressed as AMEL and MDEL. The multiplier is a statistically based factor that adjusts the LTA for the averaging periods and exceedance frequencies of the criteria/objectives and the effluent limitations. The value of the multiplier varies depending on the probability basis, the coefficient of variation (CV) of the data set, the number of samples (for AMEL) and whether it is a monthly or daily limit. Table 2 of the SIP provides pre-calculated values for the multipliers based on the value of the CV and the number of samples. Equations to develop the multipliers in place of using values in the tables are provided in Section 1.4, Step 5 of the SIP and will not be repeated here. AMELaquatic life = LTA x AMELmultiplier 95 MDELaquatic life = LTA x MDELmultiplier 99 AMEL multipliers are based on a 95th percentile occurrence probability, and the MDEL multipliers are based on the 99th percentile occurrence probability. If the number of samples is less than four (4), the default number of samples to be used is four (4). Equations provided in Section 1.4, Step 5 of the SIP are used to develop the AMEL and MDEL for aquatic life using (Table 2 of the SIP also provides this data up to two decimals). For chlorodibromomethane and the other constituents that had a reasonable potential, aquatic criterion had not been promulgated at the time of the development of this permit and AMEL and MDEL for aquatic life were unnecessary to calculate. Calculation of human health AMEL and MDEL: Step 5: For the ECA based on human health, set the AMEL equal to the ECAhuman health AMELhuman health = ECAhuman health For chlorodibromomethane: AMELhuman health = 0.401 μg/L Step 6: Calculate the MDEL for human health by multiplying the AMEL by the ratio of the MultiplierMDEL to the MultiplierAMEL. Table 2 of the SIP provides pre-calculated ratios to be used in this calculation based on the CV and the number of samples. MDELhuman health = AMELhuman health x (MultiplierMDEL / MultiplierAMEL) For chlorodibromomethane the following data were used to develop the MDELhuman health: No. of Samples Per Month CV MultiplierMDEL 99 MultiplierAMEL 95 Ratio CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-33 1 0.6 3.11 1.55 2.01 MDELhuman health = 0.401 μg/L x 2.01 = 0.806 μg/L Step 7: Select the lower of the AMEL and MDEL based on aquatic life and human health as the water-quality based effluent limit for the Order. For chlorodibromomethane, the AMELhuman health and MDELhuman health were 0.401 μg/L and 0.806 μg/L respectively. Thus, the human health criteria-based effluent limitations were more stringent and were considered in the Order. 4.3.4.1 Constituents with Reasonable Potential 4.3.4.1.1 Mercury. The RPA used effluent data from December 2014 through December 2022 and showed that there was a reasonable potential for the discharge to exceed the total recoverable mercury criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.012 µg/L and an MDEL of 0.024 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total recoverable mercury. 4.3.4.1.2 Chlorodibromomethane. The previous Order established an AMEL of 0.40 µg/L and an MDEL of 1.0 µg/L for chlorodibromomethane (dibromochloromethane). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chlorodibromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.4 µg/L and an MDEL of 0.81 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chlorodibromomethane. 4.3.4.1.3 Chloroform. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the chloroform criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for chloroform. 4.3.4.1.4 Dichlorobromomethane. The previous Order established an AMEL of 0.56 µg/L and an MDEL of 1.0 µg/L for dichlorobromomethane. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the dichlorobromomethane criteria, and therefore these effluent limitations are retained from the previous order. Using the effluent limitation calculations established in the SIP, an AMEL of 0.56 µg/L and an MDEL of 0.96 µg/L have been established in this permit. Effluent and receiving water CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-34 monitoring and reporting requirements have also been established for dichlorobromomethane. 4.3.4.1.5. Methylene Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the methylene chloride criteria; therefore, effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 4.7 µg/L and an MDEL of 9.45 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for methylene chloride. 4.3.4.1.6. Pentachlorophenol. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the pentachlorophenol criteria, and therefore effluent limitations are established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 60 µg/L and an MDEL of 120.6 µg/L have been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for pentachlorophenol. 4.3.4.1.8. Nitrate and Nitrate + Nitrite. As previously discussed, an effluent limitation for total nitrate (as N) was established through the TMDL for nitrate-nitrogen discharges to San Luis Obispo creek and was retained from the previous permit. Additionally, an effluent limitation for total nitrite (as nitrogen) is established in this order. A separate effluent limitation has not been established for nitrate+nitrite. Nitrate+nitrite is the sum of nitrate and nitrite, and therefore is duplicative of the two established effluent limitations. 4.3.4.1.9. Nitrite. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to exceed the total nitrite (as N) criteria, and therefore an effluent limitation is established in this order. Using the effluent limitation calculations established in the SIP, an AMEL of 1.0 mg/L has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for total nitrite (as N). 4.3.4.1.10. Methylene blue activated substances (MBAS). The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the MBAS criteria of 0.2 mg/L from the 2019 Basin Plan. The 0.2 mg/L effluent limitation established in this order is equivalent to the most stringent water quality objective in the 2019 Basin Plan. Effluent and receiving water monitoring and reporting requirements have also been established for MBAS. 4.3.4.1.11 Un-ionized Ammonia. The 2019 Basin Plan includes a water quality objective for un-ionized ammonia (NH3) of 0.025 mg/L. The previous Order did not establish an effluent limitation for un-ionized ammonia. The previous Order incorporated the Basin Plan objective as a receiving water limitation. From December 2014 through April 2020, the Discharger collected 93 concurrent upstream (RSW-004) and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-35 downstream (RSW-005) samples to determine un-ionized ammonia concentrations in the receiving water. The effluent caused the receiving water to exceed the Basin Plan objective on 29 occasions. Reasonable potential was found for un-ionized ammonia, and an effluent limitation and monitoring requirement were established for un-ionized ammonia. The effluent limitation of 0.025 mg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. 4.3.4.1.12. Molybdenum. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the effluent to exceed the molybdenum criteria of 10 µg/L from the 2019 Basin Plan. An effluent limitation of 10 µg/L is equivalent to the most stringent water quality objective in the Basin Plan and has been established in this permit. Effluent and receiving water monitoring and reporting requirements have also been established for molybdenum. 4.3.4.1.13. Total Dissolved Solids. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the total dissolved solids criteria of 650 mg/L in the Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for total dissolved solids. 4.3.4.1.14. Chloride. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the chloride criteria of 100 mg/L from the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for chloride. 4.3.4.1.15. Sulfate. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sulfate criteria of 100 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sulfate. 4.3.4.1.16. Sodium. The RPA based on analysis of effluent data from December 2014 through December 2022 showed that there was a reasonable potential for the discharge to cause an exceedance of the sodium criteria of 50 mg/L in the 2019 Basin Plan for the mean surface water quality objective for San Luis Obispo Creek. Effluent and receiving water monitoring and reporting requirements have also been established for sodium. 4.3.4.2 Constituents with No Reasonable Potential As detailed in Table F-8, constituents that were analyzed and received a “No” in the “RPA Result” column did not have a reasonable potential to cause or contribute to an excursion above the 126 U.S. EPA priority toxic pollutants, title 22 MCLs, or any CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-36 numeric water quality objectives included in any State Water Board plans or the 2019 Basin Plan. WQBEL’s are not included in this Order for constituents that do not demonstrate reasonable potential to cause or contribute to an instream excursion of an applicable water quality objective; however monitoring for priority toxic and title 22 pollutants is established in this Order. Most constituents with no reasonable potential are not discussed in this order. This section provides a discussion on the constituent with no reasonable potential for which an effluent limitation has not been retained from the previous order. 4.3.4.2.1 N-nitrosodimethylamine. The previous Order included an AMEL of 0.00069 µg/L and an MDEL of 0.0014 µg/L for n-nitrosodimethylamine. Several sample results analyzed during 2016 showed effluent limitation exceedances. However, in a letter dated February 9, 2017, the Discharger provided additional information to the Central Coast Water Board describing that the cause of the apparent exceedances was due to the test method used to analyze the samples. The Minimum Level (ML) established for n-nitrosodimethylamine in Appendix 4 of the SIP is 5 µg/L for samples analyzed by gas chromatography/ mass spectrometry. The Discharger was using EPA Method 1625M, an “ultra-low-level” method, which is not an approved method in 40 CFR part 136 and is not appropriate for compliance monitoring. The Discharger notified the Central Coast Water Board of its plan to return to using EPA Method 625 to measure n- nitrosodimethylamine in the effluent instead of the “ultra-low-level” the Discharger used in 2016 (i.e., EPA Method 1625M). On May 15, 2017, the Central Coast Water Board provided a written response that concurred with the Discharger regarding the return to EPA Method 625 and that the n-nitrosodimethylamine effluent concentrations reported in 2016 should not have been reported as effluent limitation exceedances because results below the ML of 5 µg/L are not considered violations according to the SIP. The RPA used effluent data from December 2014 through December 2022 that was analyzed using the correct test method and found that there was not reasonable potential for an exceedance of a water quality objective. An effluent limitation of n- nitrosodimethylamine has not been retained for this Order. Additional discussion is included in section 4.4.1 Ant-Backsliding Requirements and section 4.4.1 Antidegradation Policies of this fact sheet. 4.3.5. Whole Effluent Toxicity (WET) Aquatic toxicity is the adverse response of aquatic organisms from exposure to chemical or physical agents, or their synergistic effects in effluent or ambient water. Acute aquatic toxicity refers to adverse response (typically lethality) from a short-term exposure. Chronic aquatic toxicity generally refers to longer exposure duration and measures of both lethal and sub-lethal adverse response. WET testing protects receiving waters from the aggregate toxic effect of a mixture of pollutants that may be present in effluent. The Basin Plan establishes a narrative WQO which states that all waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-37 Survival of aquatic organisms in surface waters subjected to a waste discharge or other controllable water quality conditions shall not be less than that for the same waterbody in areas unaffected by the waste discharge or for another control water. The WET approach allows for protection of the narrative “no toxics in toxic amounts” criterion while implementing numeric criteria for toxicity. For compliance with the Basin Plan’s narrative toxicity objective and the 2022 Toxicity Provisions, this Order requires the Discharger to conduct WET testing for acute and chronic toxicity in accordance with the Test of Significant Toxicity (TST) statistical approach, as specified in section 5 of the MRP (Attachment E). 4.3.5.1. Test of Significant Toxicity (TST) In 2010, U.S. EPA endorsed the TST statistical hypothesis testing approach, described in the National Pollutant Discharge Elimination System Test of Significant Toxicity Implementation Document (EPA 833-R-10-003, 2010), Appendix A, Figure A-1 and Table A-1, as an improved hypothesis-testing tool to evaluate data from U.S EPA’s toxicity test methods. The TST hypothesis testing approach more reliably identifies toxicity—in relation to the chronic (0.25 or more) and acute (0.20 or more) mean responses of regulatory management concern—than the No Observed Effect Concentration (NOEC) hypothesis-testing approach previously used. On December 1, 2020, the State Water Board adopted Resolution No. 2020-0044, establishing the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries (ISWEBE Plan), and adopting statewide numeric WQOs for both acute and chronic toxicity and a program of implementation to control toxicity, which are collectively known as the Toxicity Provisions. The Toxicity Provisions, which were revised on October 5, 2021, standardized the regulation of aquatic toxicity for all non- oceanic surface waters.3 U.S. EPA’s Test of Significant Toxicity Design, or TST, approach is an essential component of the Toxicity Provisions as it forms the basis for utilizing numeric WQOs and acts as the primary means of determining compliance with WET effluent limitations. This Order requires application of the TST approach for statistical analysis of WET data. 4.3.5.1.1. Test of Significant Toxicity Design The TST null hypothesis (Ho) for acute toxicity is: “mean discharge IWC response ≤0.80 × mean control response”, where 0.80 is the regulatory management decision (RMD). The TST null hypothesis (Ho) for chronic toxicity is: “mean discharge IWC response ≤0.75 × mean control response”, where 0.75 is the RMD. The null hypotheses for acute and chronic toxicity described in the TST are assigned as numeric WQOs for acute and chronic toxicity in sections II.C.1 and II.C.2 of the Toxicity Provisions. A test result that rejects the null hypothesis is reported as “Pass”. A test result that does not reject this null hypothesis is reported as “Fail”. The TST approach is a t-test (formally Student’s t- 3 The Toxicity Provisions were approved by the Office of Administrative Law on April 25, 2022, and by U.S. EPA on May 1, 2023. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-38 test), a statistical analysis comparing two sets of replicate observations—in the case of WET tests, only two test concentrations (i.e., a control and IWC). The purpose of this statistical test is to determine if the means of the two sets of observations are different (i.e., if the IWC or receiving water concentration differs from the control (the test result is “Pass” or “Fail”)). The Welch’s t-test employed by the TST statistical approach is an adaptation of Student’s t-test and is used with two samples having unequal variances. The MDEL for chronic toxicity is exceeded when a chronic toxicity test, analyzed using the TST statistical approach, results in “Fail” for the sub-lethal endpoint and the “Percent Effect” is ≥0.50 for the survival endpoint or the sub-lethal endpoint if there is no survival endpoint. The MMEL for chronic toxicity is exceeded and a violation will be flagged when two or more toxicity tests initiated in a calendar month, or in consecutive calendar months, result in a “Fail” in accordance with the TST approach for any endpoint. The MDEL and MMEL for chronic toxicity are set at the IWC for the discharge and expressed in units of the TST statistical approach (“Pass” or “Fail”; “Percent Effect”). All NPDES effluent monitoring for the chronic toxicity effluent limitations shall be reported using the 100 percent effluent concentration and negative control, expressed in units of the TST. The TST hypothesis (Ho) (see above) is statistically analyzed using the IWC and a negative control. Effluent toxicity tests shall be run using a multi-concentration test design when required by Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms (EPA-821-R-02-013, 2002). Compliance with the toxicity limitation is demonstrated by rejecting the null hypothesis and reporting “Pass”. When the toxicity test results in a “Fail” the Discharger must initiate accelerated monitoring as specified in section 5.3 of the MRP. After accelerated monitoring, if conditions of chronic toxicity are found to persist, the Discharger will be required to conduct a TRE, as described in section 5.4 of the MRP. See section III.B.3 of the Toxicity Provisions for a detailed step-by-step description of the TST statistical method. 4.3.5.2. WET Reasonable Potential Analysis To determine the need for acute and/or chronic toxicity effluent limitations, the Central Coast Water Board conducted a RPA using the TST approach. In conducting the RPA, the Central Coast Water Board considered and evaluated all acute and chronic toxicity data generated during the previous permit term since the data is representative of the actual effluent quality from the Facility. Reasonable potential exists if any of the acute or chronic toxicity tests result in a “Fail” or if the percent effect at the IWC is greater than 10 percent. The IWC for Discharge Point 001 is 100 percent effluent. The Discharger conducted eight acute and 26 chronic toxicity tests using the species Pimephales promelas between October 2015 and October 2022, as shown in Table F- 10 below. Analysis using the TST approach concluded that the Discharger failed zero acute toxicity tests, and 14 chronic toxicity tests, representing a fail rate of 54 percent. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-39 After extensive City staff and consultant review, summarized in the Toxicity Reduction Evaluation Workplan Conclusion report submitted to the Central Coast Regional Water Quality Control Board on May 22, 2019, all Effluent 001 sampling events from October 2016 to October 2018 exhibited at least one of the three qualifying data interpretations of sporadic mortality, suggesting biological interference was the cause of observed toxicity. The Central Coast Water Board reviewed the TRE Workplan and maintained that the failed chronic test results would remain on record. These chronic toxicity test results were used to conclude that the discharge has reasonable potential to cause or contribute to an exceedance of chronic toxicity WQOs and that the discharge is subject to chronic toxicity effluent limitations. In addition, section III.C.5.c. of the Toxicity Provisions requires establishment of chronic toxicity effluent limitations if a POTW is authorized to discharge at a rate equal to or greater than 5.0 MGD and is required to have a pretreatment program by the terms of 40 CFR section 403.8(a). The permitted flow rate for the Facility is 5.4 MGD, and the Discharger is required to have a pretreatment program. Therefore, based on the determination of the RPA, and requirements contained in the Toxicity Provisions, the Order establishes MDEL and MMEL effluent limitations for chronic toxicity. Table F-9. Summary of Acute and Chronic Toxicity Test Results Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 10/6/2015 Pass 2.50 Survival Acute 10/4/2016 Pass 0.00 Survival Acute 10/3/2017 Pass 10.00 Survival Acute 10/30/2018 Pass 0.00 Survival Acute 10/15/2019 Pass 7.50 Survival Acute 10/28/2020 Pass 0.00 Survival Acute 10/5/2021 Pass 0.00 Survival Acute 10/4/2022 Pass 0.00 Survival Acute 10/6/2015 Pass 8.68 Growth Chronic 10/6/2015 Pass 6.78 Survival Chronic 10/4/2016 Pass -13.56 Growth Chronic 10/4/2016 Pass 13.33 Survival Chronic 10/3/2017 Fail 31.69 Growth Chronic 10/3/2017 Fail 40.68 Survival Chronic 10/24/2017 Fail 49.63 Growth Chronic 10/24/2017 Fail 68.33 Survival Chronic 11/28/2017 Pass 17.20 Growth Chronic 11/28/2017 Pass 10.91 Survival Chronic 12/12/2017 Fail 43.78 Growth Chronic 12/12/2017 Fail 58.33 Survival Chronic 8/21/2018 Fail 19.95 Growth Chronic 8/21/2018 Fail 31.67 Survival Chronic 7/31/2018 Pass 14.48 Growth Chronic CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-40 Test Initiation Date Test Result Percent Effect Test Endpoint Test Type 7/31/2018 Fail 34.48 Survival Chronic 10/30/2018 Pass 4.56 Growth Chronic 10/30/2018 Fail 18.33 Survival Chronic 10/15/2019 Pass -12.63 Growth Chronic 10/15/2019 Pass 1.75 Survival Chronic 10/28/2020 Pass -7.95 Growth Chronic 10/28/2020 Pass 0.00 Survival Chronic 10/5/2021 Pass -2.02 Growth Chronic 10/5/2021 Pass 0.00 Survival Chronic 10/4/2022 Pass 3.00 Growth Chronic 10/4/2022 Pass 0.00 Survival Chronic 4.3.5.3. Acute Aquatic Toxicity Although the Discharger reported no acute toxicity test failures from the eight acute toxicity tests conducted during the previous permit term, this permit retains annual effluent monitoring requirements for acute toxicity established in Order No. R3-2014- 0033 due to persistent failure of chronic toxicity tests during the previous permit term, which resulted in a required TRE being conducted. The Order implements federal guidelines (Regions 9 & 10 Guidance for Implementing Whole Effluent Toxicity Testing Programs) by requiring the Discharger to conduct acute species sensitivity testing as described in section 5 of the MRP (Attachment E). This Order requires the Discharger to conduct a screening test using a vertebrate and invertebrate species. After the screening test is completed, the Discharger is required to use the most sensitive species in future acute toxicity testing if the most sensitive species is found not to be Pimephales promelas. 4.3.6. Basin Plan and Bacteria Provisions 4.3.6.1. Bacteria Provisions. The Facility receives domestic wastewater and discharges to surface waters with the water contact recreation beneficial use (REC-1). Because of the nature of domestic wastewater, discharges from publicly owned treatment works with these discharge characteristics have the reasonable potential to cause or contribute to an exceedance of water quality criteria for bacteria. On August 7, 2018, the State Water Board adopted Part 3 of the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California – Bacteria Provisions and a Water Quality Standards Variance Policy (Bacteria Provisions), which establishes bacteria water quality objectives for reasonable protection of people that recreate within all surface waters, enclosed bays, and estuaries of the state that have the water contact recreation beneficial use (REC-1). Under the statewide Bacteria Provisions, the water quality objective protective of the REC-1 beneficial use is, in waters where the salinity is less than one part per thousand (ppth) 95 percent or more of the time: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-41 • The concentration of E. coli shall not exceed 100 colony forming units (cfu) per 100 milliliters (mL) as a six-week rolling geometric mean, calculated weekly. • A statistical threshold value (STV) of 320 cfu/100 mL for E. coli shall not be exceeded by more than 10 percent of the samples collected in a calendar month and calculated in a static manner. Order R3-2014-0033 established effluent limitations for coliform bacteria based on applicable water quality objectives in the Basin Plan for San Luis Obispo Creek. The bacteria water quality objectives in the Bacteria Provisions supersede numeric water quality objectives for bacteria for the REC-1 beneficial use contained in a water quality control plan prior to February 4, 2019. Because San Luis Obispo Creek salinity is less than one part per thousand (ppth) 95 percent or more of the time, this Order establishes E. coli effluent limitations for Discharge Point 001, based on the water quality objectives in the Bacteria Provisions, in place of the previous fecal coliform effluent limitations. 4.3.6.2. Dissolved Oxygen. In order to protect the beneficial uses of San Luis Obispo Creek, Order R3-2014-0033 retained an effluent limit for dissolved oxygen, prohibiting the discharge from containing a dissolved oxygen concentration of less than 4.0 mg/L or so low that it adversely affects beneficial uses. 4.3.6.3. Nitrate. San Luis Obispo Creek is included on the 303(d) List as impaired for nutrients. Central Coast Water Board Resolution R3-2005-0106 established TMDLs for nitrate for discharges to San Luis Obispo Creek. Due to federal and State anti- backsliding regulations, nitrate remains a pollutant of concern for this discharge and the monthly average effluent limitation of 10 mg/L as N is retained from the previous Order. 4.3.6.4. pH. Federal regulations, 40 CFR 133, establish technology-based effluent limitations for pH. The secondary treatment standards require the pH of the effluent to be no lower than 6.0 and no greater than 9.0 standard units. However, the Basin Plan establishes a WQO for pH of between 6.5 to 8.3 standard units for the protection of receiving waters with the beneficial use of Municipal and Domestic Supply (MUN), Agricultural Supply (AGR), and Water Recreation (REC1 and REC2). The Basin Plan establishes a WQO for pH between 7.0 to 8.5 standard units for the beneficial use of Freshwater Habitat (COLD and WARM) and Fish Spawning (SPWN). The previous Order established an effluent limitation of 6.5 to 8.3. However, since San Luis Obispo Creek has MUN, AGR, REC1, REC2, COLD, WARM, and SPWN beneficial uses, a pH effluent limitation of 7.0 to 8.3 is appropriate in order to protect all beneficial uses. This Order updates the previous effluent limitation of 6.5 to 8.3 from the previous Order, based on the water quality objective for the Municipal and Domestic Supply (MUN) beneficial use. For the protection of the COLD beneficial use, this Order applies a receiving water limitation of 7.0 to 8.3, with no change in normal ambient pH levels above 0.5. 4.3.6.5. Oil and Grease. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works has the reasonable potential to cause or contribute to an exceedance of water quality criteria for oil and CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-42 grease. The Basin Plan establishes a narrative effluent limitation for oil and grease, which states, “Waters shall not contain oils, greases, waxes, or other similar materials in concentrations that result in a visible film or coating on the surface of the water or on objects in the water, that cause nuisance, or that otherwise adversely affect beneficial uses. The previous Order contained an AMEL and MDEL of 5.0 mg/L and 10 mg/L, respectively. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.3.6.6. Floating Material. Discharge of treated wastewater through Discharge Point No. 001 shall not contain floating material, including solids, liquids, foams, and scum in concentrations that cause nuisance or adversely affect beneficial uses. This effluent limitation is consistent with the Basin Plan. 4.3.6.7. Settleable Solids. The nature of domestic, commercial, and industrial wastewater received by the Facility and similar publicly owned treatment works have the reasonable potential to cause or contribute to an exceedance of water quality criteria for settleable solids. The Basin Plan establishes a narrative effluent limitation for settleable solids, which states, “Waters shall not contain settleable material in concentrations that result in deposition of material that causes nuisance or adversely affects beneficial uses. The previous Order contained an average monthly effluent limitation (AMEL) of 0.1 mL/L. These effluent limitations are typical of similar facilities that discharge tertiary treated wastewater and are necessary to protect the narrative water quality objective. This Order retains the effluent limitations from the previous Order. 4.4. Final Effluent Limitation Considerations 4.4.1. Anti-Backsliding Requirements Sections 402(o) and 303(d)(4) of the CWA and federal regulations at 40 C.F.R. 122.44(l) prohibit backsliding in NPDES permits. These anti-backsliding provisions require effluent limitations in a reissued permit to be as stringent as those in the previous permit, with some exceptions where limitations may be relaxed. All effluent limitations in this Order are at least as stringent as the effluent limitations in the previous Order. An effluent limitation for n-nitrosodimethylamine has not been retained from the previous Order because current data analysis shows no reasonable potential. The elimination of this WQBEL is consistent with the exception to the CWA's anti-backsliding requirements expressed at §402 (0)(2)(B)(i) of the Act, which allows a reissued permit to include less stringent limitations when information is available that was not available at the time of permit issuance (other than revised regulations, guidance, or test methods), and that would have justified the application of a less stringent effluent limitation at the time of permit issuance. The removal of the limitation of n- nitrosodimethylamine is based on new data, which was generated during the term of previous Order, and which demonstrates no reasonable potential for discharges from the Facility to cause or contribute to exceedances of applicable WQOs for this pollutant. Therefore, effluent limitations for these pollutants from the previous Order are not retained in this Order. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-43 4.4.2. Antidegradation Policies 40 CFR section 131.12 requires that state water quality standards include an antidegradation policy consistent with the federal antidegradation policy. On October 28, 1968, the State Water Board established California’s antidegradation policy when it adopted Resolution Number 68-16, Statement of Policy with Respect to Maintaining the Quality of the Waters of the State. Resolution Number 68-16 requires that existing water quality be maintained unless degradation is justified based on specific findings. The State Water Board has, in State Water Board Order Number 86-17 and an October 7, 1987 guidance memorandum, interpreted Resolution Number 68-16 to be fully consistent with the federal antidegradation policy contained in 40 CFR section 131.12. Similarly, CWA section 303(d)(4)(B) and 40 CFR section 131.12 require that all permitting actions be consistent with the federal antidegradation policy. Together, the state and federal antidegradation policies are designed to ensure that a water body will not be degraded resulting from the permitted discharge. The Central Coast Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. The renewal of this NPDES permit is consistent with the anti-degradation policy because it is not expected to allow degradation of receiving water quality. No reduction in the existing level of wastewater treatment is anticipated. In addition, the renewal of the NPDES permit will not lower the surface water quality because the conditions in this Order are at least as stringent as the previous permit except for limits described in section 4.4.1 of the Fact Sheet. Specifically, the removal of the final effluent limitation for n-nitrosodimethylamine is consistent with the antidegradation policy because the discharge did not exhibit reasonable potential to exceed the water quality objective, and it is not expected to degrade the water quality of the receiving water. Effluent and receiving water monitoring for this pollutant continue to be required under this Order to ensure effluent and receiving water concentrations do not exceed the objective. 4.4.3. Stringency of Requirements for Individual Pollutants This Order contains both technology-based and water quality-based effluent limitations for individual pollutants. The technology-based effluent limitations consist of restrictions on BOD and TSS. This Order’s technology-based pollutant restrictions implement the minimum applicable federal technology-based requirements. In addition, this Order contains effluent limitations more stringent than the minimum federal technology-based requirements that are necessary to meet water quality standards. For pH, BOD, and TSS both technology-based effluent limitations and water quality-based effluent limitations are applicable. The more stringent of these effluent limitations are implemented by this Order. These limitations are not more stringent than required by the CWA. Water quality-based effluent limitations have been derived to implement water quality objectives that protect beneficial uses. Both the beneficial uses and the water quality objectives have been approved pursuant to federal law and are the applicable federal water quality standards. To the extent that toxic pollutant water CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-44 quality-based effluent limitations were derived from the CTR, the CTR is the applicable standard pursuant to 40 C.F.R. 131.38. The procedures for calculating the individual water quality-based effluent limitations for priority pollutants are based on the CTR implemented by the SIP, which was approved by U.S. EPA on May 18, 2000. Any water quality objectives and beneficial uses submitted to U.S. EPA prior to May 30, 2000, but not approved by U.S. EPA before that date, are nonetheless “applicable water quality standards for purposes of the CWA” pursuant to 40 C.F.R. 131.21(c)(1). Collectively, this Order’s restrictions on individual pollutants are no more stringent than required to implement the requirements of the CWA. 4.4.4. Summary of Final Effluent Limitations 4.4.4.1. Effluent Limitations. The following effluent limitations are applicable to the discharge of disinfected tertiary treated wastewater from the Facility at Discharge Point No. 001. Table F-10. Final Effluent Limitations – Discharge Point EFF-001 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Biochemical Oxygen Demand (BOD) 5-day at 20 degrees Celsius (°C) Milligram per liter (mg/L) 10 30 50 - - - BOD 5-day at 20°C Pounds per day (lbs/day) [1] 425 1275 2,125 - - - Total Suspended Solids (TSS) mg/L 10 30 75 - - - TSS lbs/day[1] 425 1,275 3,190 - - - pH[2],[3] standard units - - - 6.5 8.3 - Oil and Grease mg/L 5 - 10 - - - CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-45 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Settleable Solids milliliter per liter (mL/L) 0.1 - - - - - Dissolved Oxygen mg/L - - - 4.0 - - Chlorine Residual mg/L [4][5] Mercury, Total Recoverable µg/L 0.012 - 0.024 - - - Chlorodibromomethane (Dibromochloromethane) µg/L 0.401 - 0.81 - - - Chloroform µg/L 60 - 120.6 - - - Dichlorobromomethane (Bromodichloromethane) µg/L 0.56 - 0.96 - - - Methylene Chloride µg/L 4.7 - 9.45 - - - Pentachlorophenol µg/L 0.28 - 0.56 - - - Nitrate, Total (as Nitrogen (N)) mg/L 10 - - - - - Nitrite, Total mg/L 1 - - - - - Un-ionized Ammonia mg/L 0.025 - - - - - Methylene Blue Active Substances (MBAS) mg/L 0.2 - - - - - Molybdenum mg/L 0.01 - - - - - Total Dissolved Solids mg/L 650 - - - - - Chloride mg/L 100 - - - - - CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-46 Parameter Units Average Monthly Average Weekly Maximum Daily Instantaneous Minimum Instantaneous Maximum Monthly Median Sodium mg/L 50 - - - - - Sulfate mg/L 100 - - - - - Total Coliform MPN/100 mL [6] Chronic Toxicity[7] “Pass/Fail ” and Percent Effect - - “Pass” and Percent Effect <50[8] - - [9] [1] The average monthly percent removal for BOD and TSS shall not be less than 85 percent. [2] Applied as an instantaneous effluent limitation. [3] When the Discharger continuously monitors effluent pH, levels shall be maintained within specified ranges 99 percent of the time. To determine 99 percent compliance, the following conditions shall be met: • The total time during which pH is outside the range of 6.5-8.3 shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from the range of 6.5-8.3 shall exceed 30 minutes; • No single excursion shall fall outside the range of 6.0-9.0; and • When continuous monitoring is not being performed, standard compliance guidelines shall be followed (i.e., between 6.5-8.3 at all times, measured daily). [4] Compliance determination for total chlorine residual shall be based on 99 percent compliance. To determine 99 percent compliance, the following conditions shall be met: • The total time during which to the total chlorine residual values are above 0.1 mg/L (instantaneous maximum value) shall not exceed 7 hours and 26 minutes in any calendar month; • No single excursion from 0.1 mg/L shall exceed 30 minutes; • No single excursion shall exceed 2 mg/L. • When continuous monitoring is not being performed, standard compliance guidelines shall be followed. [5] Total chlorine residual monitoring is only required when chlorine is used for disinfection and or cleaning/maintenance purposes. The Discharger shall specify with the monthly, quarterly, and annual SMRs if chlorination occurred during the monitoring period. [6] Total Coliform: CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-47 • The median number of total coliform organisms in the effluent shall not exceed 2.2 MPN/100 mL as determined by results of bacteriological analyses for the last 7 days on which samples were taken; • No more than one sample shall exceed 23 MPN/100 mL total coliform in any 30- day period; • The maximum number of total coliform organisms in any sample shall not exceed 240 MPN/100 mL. [7] As specified in section 7.2 of this Order and section 5 of the Monitoring and Reporting Program (MRP) (Attachment E). [8] The Maximum Daily Effluent Limitation (MDEL) is exceeded if a chronic toxicity test using the most sensitive species results in a “Fail” at the in-stream waste concentration (IWC) for the sub-lethal endpoint measured in the test and a “Percent Effect” greater than or equal to 50 percent for the survival endpoint. [9] The Median Monthly Effluent Limitation (MMEL) is exceeded when two or more chronic toxicity tests using the most sensitive species initiated in a calendar month result in a “Fail” at the IWC for any endpoint (see section 5 of the MRP-Attachment E). 4.5. Interim Effluent Limitations – Not Applicable 4.6. Land Discharge Specifications – Not Applicable 4.7. Recycling Specifications This Order allows the production and onsite use of disinfected tertiary recycled wastewater in compliance with applicable state and local requirements regarding the production and use of reclaimed wastewater, including those requirements in the State Water Board’s Recycled Water Policy, and those established by DDW at title 22, sections 60301-60357 of the California Code of Regulations, Water Recycling Criteria. This Order includes water reclamation requirements for the Facility pursuant to the State Water Board’s Division of Drinking Water recommendations submitted to the Central Coast Water Board. This Order requires the Discharger to adhere to the requirements outlined in section 4.3 and any additional conditions pursuant to specifications in updated title 22 engineering reports approved by the State Water Board’s Division of Drinking Water. 4.8. Point of Compliance for Effluent Limitations 4.8.1. The Discharger must comply with the effluent limitations established in this order at location EFF-001. The facility includes a long concrete pipe that sends treated effluent from the facility to San Luis Obispo Creek. In previous permits, the discharge was monitored at the end of the pipe, just before it mixes with San Luis Obispo Creek. Due to safety and cost concerns, the Discharger requested to perform the majority of their compliance monitoring at the beginning of the pipe. The beginning of the pipe is referred to as EFF-001A and the end of the pipe is referred to as EFF-001B. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-48 5. RATIONALE FOR RECEIVING WATER LIMITATIONS 5.1. Surface Water Receiving water quality is a result of many factors, some unrelated to the discharge. This Order considers these factors and is designed to minimize the influence of the discharge on the receiving water. Specific water quality objectives established by the Basin Plan to meet this goal for all inland surface waters are included as receiving water limitations in section 5.1. of this Order. 6. RATIONALE FOR PROVISIONS 6.1. Standard Provisions Standard Provisions, which apply to all NPDES permits in accordance with 40 C.F.R. section 122.41, and additional conditions applicable to specified categories of permits in accordance with 40 C.F.R. section 122.42, are provided in Attachment D. The Discharger must comply with all standard provisions and with those additional conditions that are applicable under section 122.42. Sections 122.41(a)(1) and (b) through (n) of 40 C.F.R. establish conditions that apply to all state-issued NPDES permits. These conditions must be incorporated into the permits either expressly or by reference. If incorporated by reference, a specific citation to the regulations must be included in the Order. Section 123.25(a)(12) of 40 C.F.R. allows the state to omit or modify conditions to impose more stringent requirements. In accordance with 40 C.F.R. section 123.25, this Order omits federal conditions that address enforcement authority specified in 40 C.F.R. section 122.41(j)(5) and (k)(2) because the enforcement authority under the California Water Code is more stringent. In lieu of these conditions, this Order incorporates by reference California Water Code section 13387(e). 6.2. Special Provisions 6.2.1. Reopener Provisions The Order may be modified in accordance with the requirements set forth at 40 C.F.R. parts 122 and 124, to include appropriate conditions or limits based on newly available information, or to implement any, new state water quality objectives that are approved by the U.S. EPA. As effluent is further characterized through additional monitoring, and if a need for additional effluent limitations becomes apparent after additional effluent characterization, the Order will be reopened to incorporate such limitations. This Order may be reopened for modification to include an effluent limitation if monitoring establishes that the discharge causes, has the reasonable potential to cause, or contributes to an excursion above a SIP water quality objective. 6.2.2. Special Studies and Additional Monitoring Requirements 6.2.2.1. Whole Effluent Toxicity. The Basin Plan states, “All waters shall be maintained free of toxic substances in concentrations which are toxic to, or CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-49 which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Water Board.” The Basin Plan further states, “Survival of aquatic life in surface waters subjected to a waste discharge or other controllable water quality condition, shall not be less than that for the same waterbody in areas unaffected by the waste discharge…” and that effluent limitations based upon acute bioassays of effluent will be prescribed where appropriate. This permit establishes acute and chronic monitoring requirements, and chronic toxicity effluent limitations in accordance with the 2022 Toxicity Provisions, which incorporates the narrative objectives of the Basin Plan. The Order and MRP require the Discharger to conduct accelerated toxicity testing for exceedances of the acute toxicity WQOs, as described in the Toxicity Provisions, and/or chronic toxicity effluent limitations. If the accelerated testing demonstrates toxicity, the Discharger is required to submit a TRE Work Plan in accordance with U.S. EPA guidance, which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharge will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TIE process in accordance with the Work Plan if the results of toxicity testing exceed the effluent limitation or trigger for toxicity. 6.2.3. Best Management Practices and Pollution Prevention 6.2.3.1. Pollutant Minimization Program. The Discharger is required to minimize the discharge of pollutants consistent with the requirements of section 2.4.5.1 of the SIP. The goal of the Pollutant Minimization Program is to reduce all potential sources of a priority pollutant through pollutant minimization strategies to maintain the effluent concentration at or below water quality-based effluent limitations. 6.2.3.2. Salt and Nutrient Management Program. Section VI.C.3 of the previous Order required the Discharger to conduct a Salt Management Study to control levels of TDS, chloride, sodium, sulfate, and boron (collectively referred to as salts) in discharges from the Facility and attain applicable WQOs for salts in the San Luis Obispo Creek sub-basin of the Estero Bay Drainage Basin. Data from the term of the previous Order indicated the Facility has reasonable potential to cause or contribute to downstream impairment for salts loading. Therefore, in addition to effluent and receiving water monitoring for TDS, chloride, sulfate, boron and sodium, this Order requires the Discharger to continue to update and implement the Salt Management Program and provide annual reports. Additionally, the Discharger shall develop and implement a Nutrient Management Program as part of the Salt and Nutrient Management CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-50 Program, as discussed in section 6.3.3.1. of this Order, based on the Recycled Water Policy discussed in section 3.5.3. of this Fact Sheet. 6.2.4. Construction, Operation, and Maintenance Specifications 6.2.4.1 The Facility shall be operated as specified under Standard Provision 1.4 of Attachment D. 6.2.5. Special Provisions for Publicly Owned Treatment Works (POTWs) 6.2.5.1. Pretreatment. This Order contains pretreatment requirements consistent with applicable effluent limitations, national standards of performance, and toxic and performance effluent standards established pursuant to sections 208(b), 301, 302, 303(d), 304, 306, 307, 403, 404, 405, and 501 of the CWA, and amendments thereto. This permit contains requirements for the implementation of an effective pretreatment program pursuant to section 307 of the CWA; 40 CFR 35 and 403; and/or Title 23, CCR section 2233. 6.2.5.2. Collection System. The State Water Board issued General Waste Discharge Requirements for Sanitary Sewer Systems, Water Quality Order 2022-0103- DWQ (General Order) on December 6, 2022. The General Order requires public agencies that own or operate sanitary sewer systems with sewer lines one mile of pipe or greater to enroll for coverage and comply with the General Order. The General Order requires agencies to develop sanitary sewer management plans and report all sanitary sewer overflows, among other requirements and prohibitions. The General Order contains requirements for operation and maintenance of collection systems and for reporting and mitigating sanitary sewer overflows that are more extensive, and therefore, more stringent than the requirements under federal standard provisions. The Discharger obtained enrollment for regulation under the General Order 2022-0103-DWQ. 6.2.5.3. Resource Recovery from Anaerobically Digestible Material. Some POTWs choose to accept organic material such as food waste, fats, oils, and grease into their anaerobic digesters for co-digestion to increase production of methane and other biogases for energy production and to prevent such materials from being discharged into the collection system, which could cause sanitary sewer overflows. The California Department of Resources Recycling and Recovery has proposed an exemption from requiring Process Facility/Transfer Station permits where this activity is regulated under waste discharge requirements or NPDES permits. The proposed exemption is restricted to anaerobically digestible material that has been prescreened, slurried, and processed/conveyed in a closed system to be co-digested with regular POTW sludge. The proposed exemption requires that a POTW develop standard operating procedures for the proper handling, processing, tracking, and management of the anaerobically digestible material before it is received by the POTW. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-51 Standard operating procedures are required for POTWs that accept hauled food waste, fats, oil, and grease for injection into anaerobic digesters. The development and implementation of standard operating procedures for management of these materials is intended to allow the California Department of Resources Recycling and Recovery to exempt this activity from separate and redundant permitting programs. If the POTW does not accept food waste, fats, oil, or grease for resource recovery purposes, it is not required to develop and implement standard operating procedures. 6.2.5.4. Biosolids. Provisions regarding sludge handling and disposal ensure that such activities will comply with all applicable regulations. 40 C.F.R. part 503 sets forth U.S. EPA’s final rule for the use and disposal of biosolids, or sewage sludge, and governs the final use or disposal of biosolids. The intent of this federal program is to ensure that sewage sludge is used or disposed of in a way that protects both human health and the environment. U.S. EPA’s regulations require that producers of sewage sludge meet certain reporting, handling, and disposal requirements. As the U.S. EPA has not delegated the authority to implement the sludge program to the State of California, the enforcement of sludge requirements that apply to the Discharger remains under U.S. EPA's jurisdiction at this time. U.S. EPA, not the Central Coast Water Board, will oversee compliance with 40 C.F.R. part 503. 6.2.5.5. Discharges of Stormwater. Discharges of stormwater from POTWs with a design capacity greater than 1.0 MGD are applicable for coverage under General State Water Board Order No. 2014-0057-DWQ, NPDES General Permit No. CAS000001, Waste Discharge Requirements for Dischargers of Stormwater Associated with Industrial Activities Excluding Construction Activities. 6.2.6. Other Special Provisions 6.2.6.1. Recycled Water Policy Salt/Nutrient Management Plan. This Order requires the Discharger to develop and implement a Salt/Nutrient Management Plan. This requirement is based on the Recycled Water Policy. 6.2.6.2. Climate Change Adaptation Program. On March 7, 2017, the State Water Board adopted a resolution in recognition of the challenges posed by climate change that requires a proactive approach to climate change in all State Water Board actions, including drinking water regulation, water quality protection, and financial assistance (Resolution 2017- 0012). The resolution lays the foundation for a response to climate change that is integrated into all State Water Board actions, by giving direction to the State Water Board divisions and encouraging coordination with the regional water quality control boards. This Order requires the Discharger to implement and submit a Climate Change Adaptation Program. The Central Coast Water Board is addressing the threats of climate change and flooding by including provisions in new and reissued orders that ensure climate change mitigation and adaptation strategies are implemented. There is widespread scientific CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-52 consensus that climate change is occurring and will continue at an accelerating rate into the future. Extreme weather events, including drought, high-intensity precipitation, flooding, and extreme heat have occurred through much of California in recent years and are projected to increase in frequency, extent, or intensity due to climate change. Climate change has the potential to impact discharging facilities through inundation, storm impacts, and erosion, increasing the risk of accidental discharge that results in discharge permit violations. These events have significant implications for wastewater treatment and operations, such as increased corrosion, deposition of solids, infiltration, overflows, inundation of facilities, impairment of treatment processes, and disruption of power or electrical components. Due to the long-term nature of these risks, there is a need to avoid piecemeal or reactionary adaptation and instead undertake proactive, long-term planning with consideration of various adaptation strategies that both keep facilities safe, maintain safe discharging practices, and avoid impacts to resources. A description of the actions taken by the Discharger are described in section 2.5 – Response to Climate Change of this Order. These requirements are consistent with 40 CFR section 122.41(e), requiring permittees to ensure compliance through proper operation and maintenance of facilities, including installation and operation of appropriate auxiliary and backup facilities, and they are authorized pursuant to Water Code section 13383. (In re the City of Oceanside, Fallbrook Public Utilities Dist. And the Southern California Alliance of Publicly Owned Treatment Works, State Water Board Order WQ 2021- 0005, February 12, 2021 at p. 26.) The Los Angeles Water Board understands that the cost of preparing such a plan could be significant (estimated cost range of $25,000-$60,000), but "the costs of ensuring resilient infrastructure to protect water quality against the effects of climate change is warranted." (Fallbrook, at p. 27.) 6.2.7. Compliance Schedules – Not Applicable 7. RATIONALE FOR MONITORING AND REPORTING REQUIREMENTS CWA section 308 and 40 C.F.R. sections 122.41(h), (j)-(l), 122.44(i), and 122.48 require that all NPDES permits specify monitoring and reporting requirements. Sections 13267 and 13383 of the California Water Code also authorize the Central Coast Water Board to establish monitoring, inspection, entry, reporting, and recordkeeping requirements related to discharges to navigable waters or publicly owned treatment works, with section 13267 being the specific statute authorizing all such activities pertaining to the State Water Board’s Water Quality Control Policy for Recycled Water. The MRP, Attachment E of this Order, establishes monitoring, reporting, and recordkeeping requirements that implement federal and state requirements. The following provides the rationale for the inclusion of the monitoring and reporting requirements contained in the MRP for this facility to ensure compliance with Order requirements to ensure protection of water quality and beneficial uses. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-53 The Central Coast Water Board has considered the cost and need for monitoring and reporting generally in this NPDES permit. The discharger has provided the Central Coast Water Board with an estimation of its monitoring and reporting costs here, which are $226,860 for five years. Although the costs are significant, the costs are reasonable considering the nature of the wastewater discharge and because they result in critical data required under the Clean Water Act and which are needed to evaluate water quality generally, the impacts of the discharges on human and aquatic and benthic health, and water quality specifically, and to ensure that beneficial uses are protected. The requirements are generally comparable to other inland dischargers in the region. 7.1. Influent Monitoring In addition to influent flow monitoring, monitoring for BOD5 and TSS is required to determine compliance with the Order’s percent removal requirement for these pollutants and to assess plant performance. Influent monitoring requirements have been retained from the previous Order. 7.2. Effluent Monitoring Effluent monitoring is necessary to determine compliance with effluent limitations and evaluate compliance with applicable water quality objectives and criteria. Effluent monitoring requirements have been retained from the previous Order for Discharge Point 001, with some exceptions. Effluent monitoring for fecal coliform has been removed and replaced with E. coli monitoring to be consistent with the updated Bacteria Provisions. Effluent monitoring frequency has been increased in this Order to monthly for those pollutants with a reasonable potential to cause or contribute to an exceedance of a water quality standards and for which effluent limitations were established: mercury, chlorodibromomethane, chloroform, dichlorobromomethane, methylene chloride, pentachlorophenol, nitrite (as N), un- ionized ammonia, MBAS, total dissolved solids, sulfate, chloride, and sodium. Chronic toxicity monitoring has increased to monthly to reflect the requirements of the updated Toxicity Provisions. A quarterly effluent monitoring requirement has been established for hardness to assist with the next permit’s reasonable potential analysis. An annual effluent monitoring frequency has been established for results of the reasonable potential analysis and the 2019 Basin Plan objectives. 7.3. Whole Effluent Toxicity Testing Requirements Acute and chronic toxicity monitoring requirements and chronic toxicity effluent limitations have been established in this Order in accordance with the 2020 Toxicity Provisions in the ISWEBE Plan. An acute toxicity test is conducted over a short time period and measures mortality. A chronic toxicity test is conducted over a longer period of time and may measure mortality, reproduction, and growth. For this permit, chronic toxicity in the discharge was evaluated using U.S. EPA’s 2010 TST hypothesis testing approach and is expressed as “Pass” or “Fail” for the median monthly summary results and “Pass” or “Fail” and “Percent Effect” for each individual acute and chronic toxicity result. The chronic toxicity effluent limitations CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-54 protect the narrative WQO in the Basin Plan and comply with the requirement in the Toxicity Provisions to establish chronic effluent limitations for Facilities with permitted discharges greater than 5.0 MGD and a pretreatment program. This Order requires the Discharger to submit an updated TRE Work Plan submitted pursuant to Order No. R9-2014-0033 within 90 days of the effective date of the Order. The TRE Work Plan must describe steps the Discharger intends to follow if the effluent limitation for chronic toxicity is exceeded. If a routine acute and/or chronic toxicity test results in a “Fail” at the IWC, this Order requires the Discharger to conduct accelerated monitoring to determine the cause of the toxicity. A TRE is required when the Discharger has any combination of two or more MDEL or MMEL violations within a single calendar month or within two successive calendar months. In addition, if other information indicates toxicity (e.g., results of additional monitoring, fish kills, intermittent recurring toxicity, etc.), then the Central Coast Water Board may require a TRE. If a TRE is required, the Discharger is required to submit a detailed TRE Work Plan in accordance with U.S. EPA guidance which shall include further steps taken by the Discharger to investigate, identify, and correct the causes of toxicity; actions the Discharger will take to mitigate the effects of the discharge and prevent the recurrence of toxicity; and a schedule for these actions. This provision also includes requirements to conduct the TRE/TlE process in accordance with the submitted work plan if the results of toxicity testing exceed the effluent limitations for chronic toxicity. This Order retains annual acute toxicity monitoring requirements and establishes monthly chronic toxicity monitoring requirements based on the RPA determination for toxicity using the TST approach and the Toxicity Provisions. Refer to section 5 of the MRP (Attachment E). 7.4. Recycled Water Monitoring Recycled water monitoring is necessary to evaluate compliance with recycling specifications detailed in section 4.3 of this Order. 7.5. Receiving Water Monitoring 7.5.1. Surface Water Surface water receiving water requirements are necessary to evaluate compliance with water quality objectives, WQBELs, and the protection of beneficial uses. Surface water monitoring requirements have been retained from Order R3-2014-0033 for Discharge Point 001, with some changes in sampling frequency and additional constituents to monitor. Annual monitoring for CTR and title 22 pollutants has been included in this Order because it had not been required historically and is necessary to obtain the background (B) concentration data that will be used for the next permit’s reasonable potential analysis. Quarterly sampling of E.coli has been included in this Order to be consistent with the statewide Bacteria Provisions. Sampling frequency for flow, turbidity, color, pH, dissolved oxygen, and temperature have been decreased from weekly to CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-55 monthly due to personnel safety concerns at sampling locations in the creek. Monthly monitoring of these parameters will provide sufficient data of the receiving water. Quarterly monitoring of boron and monthly monitoring of TDS, chloride, sodium, and sulfate have been included in this Order to provide an understanding of salts concentrations in the receiving water. The addition of quarterly monitoring of hardness in this Order will assist with the next permit’s reasonable potential analysis. 7.5.2. Groundwater Consistent with the previous permit, groundwater monitoring requirements have not been included. 7.6. Other Monitoring Requirements 7.6.1. Discharge Monitoring Report-Quality Assurance (DMR-QA) Study Program Under the authority of section 308 of the CWA (33 U.S.C. 1318), U.S. EPA requires major and selected minor dischargers under the NPDES Program to participate in the annual DMR-QA Study Program. The DMR-QA Study Program evaluates the analytical ability of laboratories that routinely perform or support self-monitoring analyses required by NPDES permits. There are two options to satisfy the requirements of the DMR-QA Study Program: (1) The Discharger can obtain and analyze a DMR-QA sample as part of the DMR-QA Study; or (2) Per the waiver issued by U.S. EPA to the State Water Board, the Discharger can submit the results of the most recent Water Pollution Performance Evaluation Study from its own laboratories or its contract laboratories. A Water Pollution Performance Evaluation Study is similar to the DMR-QA Study. Thus, it also evaluates a laboratory’s ability to analyze wastewater samples to produce quality data that ensure the integrity of the NPDES Program. The Discharger shall ensure that the results of the DMR-QA Study or the results of the most recent Water Pollution Performance Evaluation Study are submitted annually to the State Water Board. The State Water Board’s Quality Assurance Program Officer will send the DMR-QA Study results or the results of the most recent Water Pollution Performance Evaluation Study to U.S. EPA’s DMR-QA Coordinator and Quality Assurance Manager. 7.6.2. Annual Volumetric Reporting of Wastewater and Recycled Water To establish a realistic estimate of statewide recycled water use and potential for increased recycled water use statewide, the Recycled Water Policy requires Dischargers to report the volume of treated wastewater and recycled water. The annual report will meet implementation needs of the Recycled Water Policy and fill data gaps for additional statewide water planning efforts. The burden and cost of preparing the report is reasonable and consistent with the interest of the state in maintaining water quality and developing alternative water supplies to increase water resiliency. The Discharger shall ensure that all volumetric reporting requirements from this Order are submitted in electronic format via the State Water Board’s Internet GeoTracker system at http://geotracker.waterboards.ca.gov/. The State Water Board will evaluate CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-56 progress towards the recycled water goals in the Recycled Water Policy and evaluate the need to update the recycled water goals in the future based on consistent statewide data. 7.6.3. Biosolids/Sludge Monitoring Biosolids monitoring shall be reported in the annual report in accordance with 40 C.F.R. 503. Biosolids monitoring requirements have been retained from the previous Order. 7.6.4. Pretreatment Monitoring Pretreatment monitoring shall be reported in the annual report in accordance with requirements in 40 C.F.R. 403.8. Pretreatment monitoring requirements have been retained from the previous Order. 7.6.5. Salt and Nutrient Management Plan Reporting Salt and Nutrient Management Plan reporting requirements have been retained in this Order to help identify and reduce salt and nutrient loading in effluent. This salt/nutrient management report shall be included as a separate report from the annual report. 7.6.6. Discharge to Evaporation Ponds Reports of discharge to and from the Facility’s evaporation ponds are required pursuant to California Water Code section 13383. Any costs incurred with this reporting are expected to be minimal. The reporting is necessary to ensure compliance with the provisions of this Order, inform follow-up actions in the event of noncompliance with the provisions of this Order, and to protect human health and water quality. 8. CONSIDERATION OF NEED TO PREVENT NUISANCE AND WATER CODE SECTION 13241 FACTORS The requirements set forth in subsections 2.4 and 4.3 of this Order are included to implement state law only. These requirements are not required or authorized under the federal CWA; consequently, violations of these requirements are not subject to the enforcement remedies that are available for NPDES violations. As required by Water Code section 13263, the Central Coast Water Board has considered the need to prevent nuisance and the factors listed in Water Code section 13241 in establishing the state law provisions/requirements. The Central Coast Water Board finds, on balance, that the state law requirements in this Order are reasonably necessary to prevent nuisance and to protect beneficial uses identified in the Basin Plan, and the section 13241 factors are not sufficient to justify failing to protect those beneficial uses. 8.1. Need to prevent pollution or nuisance In establishing effluent limitations in this Order, the Central Coast Water Board has considered state law requirements to prevent pollution or nuisance as defined in section 13050, subdivisions (l) and (m), of the Water Code. The requirements in this CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-57 Order, including those set forth in subsections 2.4 and 4.3, will prevent pollution and nuisance. 8.2. Past, present, and probable future beneficial uses of water Chapter 2 of the Basin Plan identifies designated beneficial uses for water bodies in the Central Coast Region. Beneficial uses of water relevant to this Order are also identified above in sections 3.3.1 of this Fact Sheet. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order, including those set forth in sections 2.4 and 4.3 of this Order. Accordingly, the requirements herein protect and augment the past, present and probable future beneficial uses of the water. 8.3. Environmental characteristics of the hydrographic unit under consideration, including the quality of water available thereto The environmental characteristics of this watershed are discussed in the Basin Plan, as well as available in State of the Watershed reports and the State’s CWA Section 303(d) List of impaired waters. The environmental characteristics of the hydrographic unit, including the quality of available recycled water that may be produced as a result of this Order will be improved by compliance with the requirements of this Order. 8.4. Water quality conditions that could reasonably be achieved through the coordinated control of all factors which affect water quality in the area The water quality standards necessary to protect beneficial uses of San Luis Obispo Creek Sub-Basin of the Estero Bay Drainage Basin can reasonably be achieved through the coordinated control of all factors that affect water quality in the area, including the conservation of water and/or the production of recycled water authorized by this Order. For example, the water quality in the watershed and/or groundwater basin could be improved through the addition or use of recycled water authorized by this Order, which meets title 22 standards. The Central Coast Water Board has taken this factor into account in establishing effluent limitations in the Order. 8.5 Economic Considerations The Permittee presented evidence regarding cost of monitoring but did not present additional evidence concerning other economic considerations related to this Order, such as the benefits of producing recycled water and benefits resulting from protection of beneficial uses of San Luis Obispo Creek. The Central Coast Water Board has considered the economic impact of requiring certain provisions pursuant to state law, including the costs of conducting feasibility studies for recycling, conservation, and climate change. Any additional costs associated with producing any study are reasonably necessary to prevent nuisance and protect beneficial uses identified in the Basin Plan and to improve the water supply resiliency. The failure to consider conservation or recycled water could result in the loss of, or impacts to, beneficial uses, which would have a detrimental economic impact, particularly given the effects on beneficial uses and supplies of water from the drought and climate change. Economic considerations related to costs of CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-58 compliance are therefore not sufficient, in the Central Coast Water Board’s determination, to justify failing to prevent nuisance and protect beneficial uses. 8.6 The need for developing housing within the region The Central Coast Water Board does not anticipate that these state law requirements will adversely impact the need for housing in the area. To the contrary, this Order helps address the need for housing by controlling pollutants in discharges and by allowing the reuse and exportation of recycled water for use in the area. Both of these things will improve the quality of local surface and groundwater, as well as water supply generally. This may in turn increase the region’s capacity to support continued housing development. Therefore, the potential for developing housing in the area will be facilitated by the conservation of water, or reuse or the production of recycled water, under this permit. 8.7. Need to develop and use recycled water The State Water Board’s Recycled Water Policy requires the Central Coast Water Board to encourage the use of recycled water. In addition, as discussed immediately above, a need to develop and use recycled water exists within the region, especially during times of drought. To encourage recycling, the Permittee is required by this Order to continue to explore the feasibility of recycling to maximize the beneficial reuse of tertiary treated effluent and to report on its recycled water production and use. The Discharger shall submit an update to this feasibility investigation as part of the submittal of the Report of Waste Discharge (ROWD) for the next permit renewal. 9. PUBLIC PARTICIPATION The Central Coast Water Board is considering the issuance of WDRs that will serve as an NPDES permit for the City of San Luis Obispo Water Resource Recovery Facility. As a step in the WDR adoption process, Central Coast Water Board staff developed tentative WDRs and encourages public participation in the WDR adoption process. 9.1. Notification of Interested Persons The Central Coast Water Board notified the Discharger and interested agencies and persons of its intent to prescribe WDRs for the discharge and provided an opportunity to submit written comments and recommendations. Notification was provided via the Central Coast Water Board’s website and e-mail subscription service. The public can access the agenda and any changes in dates and locations through the Central Coast Water Board’s website at http://www.waterboards.ca.gov/centralcoast/ 9.2. Written Comments Interested persons were invited to submit written comments on December 14, 2023, concerning these tentative WDRs. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-59 To be fully responded to by staff and considered by the Central Coast Water Board, the written comments were due at the Central Coast Water Board office by 5:00 p.m. on January 16, 2024. The Central Coast Water Board will hold a public hearing on the tentative WDRs during its regular Board meeting on the following date and time and at the following location: Date: April 18-19, 2024 Time: 9:00 am-5:00 pm Location: Link to video and teleconference were provided at https://www.waterboards.ca.gov/centralcoast/board_info/age ndas/2024/2024_agendas.html Interested persons are invited to attend. At the public hearing, the Central Coast Water Board will hear testimony pertinent to the discharge, WDRs, and permit. For accuracy of the record, important testimony was requested in writing. 9.4. Reconsideration of Waste Discharge Requirements Any person aggrieved by this action of the Central Coast Water Board may petition the State Water Board to review the action in accordance with Water Code section 13320 and California Code of Regulations, title 23, sections 2050 and following. The State Water Board must receive the petition by 5:00 p.m., within 30 calendar days of the date of adoption of this Order at the following address, except that if the thirtieth day following the date of this Order falls on a Saturday, Sunday, or state holiday, the petition must be received by the State Water Board by 5:00 p.m. on the next business day: State Water Resources Control Board Office of Chief Counsel P.O. Box 100, 1001 I Street Sacramento, CA 95812-0100 Or by email at waterqualitypetitions@waterboards.ca.gov For instructions on how to file a petition for review, see the State Water Board’s website on instructions for filing water quality petitions at: https://www.waterboards.ca.gov/public_notices/petitions/water_quality/wqpetition_i nstr.shtml. 9.5. Information and Copying The Report of Waste Discharge, other supporting documents, and comments received are on file and may be inspected at the address above at any time between 8:00 a.m. and 5:00 p.m., Monday through Friday. Copying of documents may be arranged through the Central Coast Water Board by calling (805) 549- 3147. CITY OF SAN LUIS OBISPO DRAFT ORDER R3-2024-0001 WATER RESOURCE RECOVERY FACILITY NPDES CA0049244 ATTACHMENT F – FACT SHEET F-60 9.6. Register of Interested Persons Any person interested in being placed on the mailing list for information regarding the WDRs and NPDES permit should contact the Central Coast Water Board, reference this facility, and provide a name, address, and phone number. 9.7. Additional Information Requests for additional information or questions regarding this order should be directed to Sarah Crable at (805) 549-3706 or Sarah.Crable@waterboards.ca.gov or Arwen Wyatt-Mair at (805) 542-4695 or Arwen.Wyattmair@waterboards.ca.gov. 114 From:Patrick McGrath <eids.fa.sender@workflow.email.us-ashburn-1.ocs.oraclecloud.com> Sent:Thursday, June 20, 2024 9:49 PM To:McGrath, Patrick Subject:FYI: Document (Requester Change Order) 617251 (Requisition 34233) Changed Attachments:PO_617251_6.pdf This message is from an External Source. Use caution when deciding to open attachments, click links, or respond. Access this task in the Workspace Application Document (Requester Change Order) 617251 (Requisition 34233) Changed Details Assignee Daniel Clancy Patrick McGrath From Patrick McGrath Assigned Date 06/20/2024 21.48 Expiration Date 07/20/2024 21.48 Task Number 2393557 Sold-to Legal Entity City of San Luis Obispo Order 617251 Procurement BU City of San Luis Obispo Buyer Daniel Clancy Justification Change Order Details Change Order 6 Description Blanket PO - Biosolids Hauling Initiating Party Requester Creation Date 06/20/2024 10.24 New Order Amount 600,000.00 USD Order Details Supplier Engel & Gray, Inc Supplier Site Main Ship-to Location Water Resource Recovery Supplier Order Description FY Open PO - 23-24 - Blanket PO - Biosolid Hauling Note to Supplier FY Open PO - 23-24 - Blanket PO - Biosolid Hauling - PO for attached FY 23-24 Open PO - This is an estimate PO and is not a guarantee the City will purchase the total amount Requisitioning BU City of San Luis Obispo Requisition 34233 Requester Patrick McGrath 115 Cost Center 6104 Attachments PO_617251_6.pdf Purchase Order 617251 Order Date 18-AUG-2023 Change Order 6 Change Order Date 21-JUN-2024 Revision 3 Ordered 600,000.00 USD INCLUDE PURCHASE ORDER NUMBER ON ALL INVOICES & CORRESPONDENCE SEND ALL INVOICES TO AP@SLOCITY.ORG INCLUDE DELIVER TO CITY STAFF CONTACT NAME ON ALL INVOICES Sold To City of San Luis Obispo 990 Palm Street SAN LUIS OBISPO, CA 93401 Supplier Engel & Gray, Inc 745 W. Betteravia Rd. SANTA MARIA, CA 93454SANTA BARBARA Bill To City of San Luis Obispo 990 Palm Street SAN LUIS OBISPO, CA 93401SAN LUIS OBISPO UNITED STATES Ship To 35 Prado Road SAN LUIS OBISPO, CA 93401SAN LUIS OBISPO UNITED STATES Notes USD = US Dollar FY Open PO - 23-24 - Blanket PO - Biosolid Hauling - PO for attached FY 23-24 Open PO - This is an estimate PO and is not a guarantee the City will purchase the total amount Customer Account Number Supplier Number Payment Terms Freight Terms FOB Shipping Method 10193 Net 30 Destination Confirm To Deliver To Contact Daniel Clancy Patrick McGrath Phone 1-805-781-7510 Line Item Price Quantity UOM Ordered Taxable 1 Blanket PO - Biosolid Hauling 600,000.00 Promised 600,000.00 08/23/2023 Requested 08/23/2023 Requested and Promised Dates correspond to the date of arrival at the Ship-to Location. Line Total 600,000.00 Total 600,000.00 1 Purchase Order 617251 Change Order 6 Authorized By: 2 Purchase Order 617251 Proprietary and Confidential Contract Terms and Conditions Purchase Order Terms and Conditions Standard Purchase Order Terms & Conditions 1. Acceptance. By delivering the ordered goods or commencing performance under this Purchase Order, ("Order") supplier agrees to the general terms, specifications, and conditions in or referenced by this document. If supplier and The City of San Luis Obispo ("City") have entered into a contract outside of this Order, the terms and conditions set forth in the contract shall prevail. Supplier's additional or different terms and conditions are expressly excluded from this Order and the City does not agree to such terms or conditions, unless such agreement is made expressly, in writing by the City's authorized representative, or a contract has been signed outside of this Order between the Supplier and The City. 2. Business License & Tax. Supplier must have a valid City of San Luis Obispo business tax certificate prior to the execution of the contract. Additional information regarding the City's business tax program may be obtained by calling (805) 781-7134. 3. Ability to Perform. Supplier warrants that it possesses, or has arranged through subcontracts, all capital and other equipment, labor, materials, and licenses necessary to carry out and complete the work hereunder in compliance with any and all federal, state, county, city, and special district laws, ordinances, and regulations. 4. Warranties. Supplier warrants that all goods delivered will be free from defects in workmanship, material, and manufacture; are new (not refurbished or reconditioned) unless otherwise stated in this Order; are of merchantable quality and fit for the purpose intended by the City to the extent that purpose has been disclosed to Supplier; complies with the requirements of this Order; and complies with all applicable laws and regulations. Supplier also warrants that all services performed under this Order shall be rendered in a good and workmanlike manner by skilled personnel in compliance with all applicable laws and regulations. 5. Changes. No change or modification in terms may be made without express authorization, in writing by the City's authorized representative. 6. Delivery. Supplier agrees that time is of the essence to delivery and any other performance required under this Order. No charge for delivery, parcel post, packing, cartage, insurance, license fees, permits, or any other purpose will be paid by the City unless it is expressly included on the face of this Order. Supplier must arrange for the lowest- cost transportation and prepay and add freight to its invoice. If delivery is made by a carrier, an itemized delivery ticket must be attached to the outside of the package. Each container or package must be marked with the Order number. 7. Laws to be Observed. Supplier shall keep itself fully informed of and shall observe and comply with all applicable state and federal laws and county and City of San Luis Obispo ordinances, regulations and adopted codes during its performance of the work. 8. Payment of Taxes. The contract prices shall include full compensation for all taxes that Supplier is required to pay. 9. Permits and Licenses. Supplier shall procure all permits and licenses, pay all charges and fees, and give all notices necessary. 10. Safety Provisions. Supplier shall conform to the rules and regulations pertaining to safety established by OSHA and the California Division of Industrial Safety Public and Employee Safety. Whenever Supplier's operations create a condition hazardous to the public or City employees, it shall, at its expense and without cost to the City, furnish, erect and maintain such fences, temporary railings, barricades, lights, signs and other devices and take such other protective measures as are necessary to prevent accidents or damage or injury to the public and employees. 11. Preservation of City Property. Supplier shall provide and install suitable safeguards, approved by the City, to protect City property from injury or damage. If City property is injured or damaged as a result of Supplier's operations, it shall be replaced or restored at Supplier's expense. The facilities shall be replaced or restored to a condition as good as when the Supplier began work 12. Immigration Act of 1986. Supplier warrants on behalf of itself and all sub-suppliers engaged for the performance of this work that only persons authorized to work in the United States pursuant to the Immigration Reform and Control Act of 1986 and other applicable laws shall be employed in the performance of the work hereunder. 13. Supplier Non-Discrimination. In the performance of this work, Supplier agrees that it will not engage in, nor permit such sub-suppliers as it may employ, to engage in discrimination in the employment of persons because of age, race, color, sex, national origin or ancestry, sexual orientation, or religion of such persons. 14. Work Delays. Should Supplier be obstructed or delayed in the work required to be done hereunder by changes in the work or by any default, act, or omission of the City, or by strikes, fire, earthquake, or any other Act of God, or by the inability to obtain materials, equipment, or labor due to federal government restrictions arising out of defense or war programs, then the time of completion may, at the City's sole option, be extended for such periods as may be agreed upon by the City and the Supplier. 15. Payment Terms. The City's payment terms are 30 days from the receipt of an original invoice and acceptance by the City of the services provided by Supplier (Net 30). 16. Inspection. Supplier shall furnish City with every reasonable opportunity for City to ascertain that the services of Supplier are being performed in accordance with the requirements and intentions of this contract. All work done and all materials furnished, if any, shall be subject to the City's inspection and approval. The inspection of such work shall not relieve Supplier of any of its obligations to fulfill its contract requirements. 17. Audit. The City shall have the option of inspecting and/or auditing all records and other written materials used by Supplier in preparing its invoices to City as a condition precedent to any payment to Supplier. 18. Interests of Supplier. Supplier covenants that it presently has no interest, and shall not acquire any interest direct or indirect or otherwise, which would conflict in any manner or degree with the performance of the work hereunder. Supplier further covenants that, in the performance of this work, no sub-Supplier or person having such an interest shall be employed. Supplier certifies that no one who has or will have any financial interest in performing this work is an officer or employee of the City. It is hereby expressly agreed that, in the performance of the work hereunder, Supplier shall at all times be deemed an independent Supplier and not an agent or employee of the City. 19. Hold Harmless and Indemnification. (a) Non-design, non-construction Professional Services: To the fullest extent permitted by law (including, but not limited to California Civil Code Sections 2782 and 2782.8), Consultant shall indemnify, defend, and hold harmless the City, and its elected officials, officers, employees, volunteers, and agents ("City Indemnitees"), from and against any and all causes of action, claims, liabilities, obligations, judgments, or damages, including reasonable legal counsels' fees and costs of litigation ("claims"), arising out of the Consultant's performance or Consultant's failure to perform its obligations under this Agreement or out of the operations conducted by Consultant, including the City's active or passive negligence, except for such loss or damage arising from the sole negligence or willful misconduct of the 3 Purchase Order 617251 Proprietary and Confidential City. In the event the City Indemnitees are made a party to any action, lawsuit, or other adversarial proceeding arising from Consultant's performance of this Agreement, the Consultant shall provide a defense to the City Indemnitees or at the City's option, reimburse the City Indemnitees their costs of defense, including reasonable legal fees, incurred in defense of such claims. (b) Non-design, construction Professional Services: To the extent the Scope of Services involve a "construction contract" as that phrase is used in Civil Code Section 2783, this paragraph shall apply in place of paragraph A. To the fullest extent permitted by law (including, but not limited to California Civil Code Sections 2782 and 2782.8), Consultant shall indemnify, defend, and hold harmless the City, and its elected officials, officers, employees, volunteers, and agents ("City Indemnitees"), from and against any and all causes of action, claims, liabilities, obligations, judgments, or damages, including reasonable legal counsels' fees and costs of litigation ("claims"), arising out of the Consultant's performance or Consultant's failure to perform its obligations under this Agreement or out of the operations conducted by Consultant, except for such loss or damage arising from the active negligence, sole negligence or willful misconduct of the City. In the event the City Indemnitees are made a party to any action, lawsuit, or other adversarial proceeding arising from Consultant's performance of this Agreement, the Consultant shall provide a defense to the City Indemnitees or at the City's option, reimburse the City Indemnitees their costs of defense, including reasonable legal fees, incurred in defense of such claims. (c) Design Professional Services: In the event Consultant is a "design professional", and the Scope of Services require Consultant to provide "design professional services" as those phrases are used in Civil Code Section 2782.8, this paragraph shall apply in place of paragraphs A or B. To the fullest extent permitted by law (including, but not limited to California Civil Code Sections 2782 and 2782.8) Consultant shall indemnify, defend and hold harmless the City and its elected officials, officers, employees, volunteers and agents ("City Indemnitees"), from and against all claims, damages, injuries, losses, and expenses including costs, attorney fees, expert consultant and expert witness fees arising out of, pertaining to or relating to, the negligence, recklessness or willful misconduct of Consultant, except to the extent caused by the sole negligence, active negligence or willful misconduct of the City. Negligence, recklessness or willful misconduct of any subcontractor employed by Consultant shall be conclusively deemed to be the negligence, recklessness or willful misconduct of Consultant unless adequately corrected by Consultant. In the event the City Indemnitees are made a party to any action, lawsuit, or other adversarial proceeding arising from Consultant's performance of this Agreement, the Consultant shall provide a defense to the City Indemnitees or at the City's option, reimburse the City Indemnitees their costs of defense, including reasonable legal fees, incurred in defense of such claims. In no event shall the cost to defend charged to Consultant under this paragraph exceed Consultant's proportionate percentage of fault. However, notwithstanding the previous sentence, in the event one or more defendants are unable to pay its share of defense costs due to bankruptcy or dissolution of the business, Consultant shall meet and confer with other parties regarding unpaid defense costs. (d) The review, acceptance or approval of the Consultant's work or work product by any indemnified party shall not affect, relieve or reduce the Consultant's indemnification or defense obligations. This Section survives completion of the services or the termination of this contract. The provisions of this Section are not limited by and do not affect the provisions of this contract relating to insurance. 20. Contract Assignment. Supplier shall not assign, transfer, convey or otherwise dispose of the contract, or its right, title or interest, or its power to execute such a contract to any individual or business entity of any kind without the previous written consent of the City. 21. Termination for Convenience. The City may terminate all or part of this Agreement for any or no reason at any time by giving 30 days written notice to Contractor. Should the City terminate this Agreement for convenience, the City shall be liable as follows: (a) for standard or off-the-shelf products, a reasonable restocking charge not to exceed ten (10) percent of the total purchase price; (b) for custom products, the less of a reasonable price for the raw materials, components work in progress and any finished units on hand or the price per unit reflected on this Agreement. For termination of any services pursuant to this Agreement, the City's liability will be the lesser of a reasonable price for the services rendered prior to termination, or the price for the services reflected on this Agreement. Upon termination notice from the City, Contractor must, unless otherwise directed, cease work and follow the City's directions as to work in progress and finished goods. 22. Termination. If during the term of the contract, the City determines that the Contractor is not faithfully abiding by any term or condition contained herein, the City may notify the Contractor in writing of such defect or failure to perform. This notice must give the Contractor a 10 (ten) calendar day notice of time thereafter in which to perform said work or cure the deficiency. If the Contractor has not performed the work or cured the deficiency within the ten days specified in the notice, such shall constitute a breach of the contract and the City may terminate the contract immediately by written notice to the Contractor to said effect.Thereafter, neither party shall have any further duties, obligations, responsibilities, or rights under the contract except, however, any and all obligations of the Contractor's surety shall remain in full force and effect, and shall not be extinguished, reduced, or in any manner waived by the terminations thereof. In said event, the Contractor shall be entitled to the reasonable value of its services performed from the beginning date in which the breach occurs up to the day it received the City's Notice of Termination, minus any offset from such payment representing the City's damages from such breach."Reasonable value" includes fees or charges for goods or services as of the last milestone or task satisfactorily delivered or completed by the Contractor as may be set forth in the Agreement payment schedule; compensation for any other work, services or goods performed or provided by the Contractor shall be based solely on the City's assessment of the value of the work-in-progress in completing the overall work scope. The City reserves the right to delay any such payment until completion or confirmed abandonment of the project, as may be determined in the City's sole discretion, so as to permit a full and complete accounting of costs.In no event, however, shall the Contractor be entitled to receive in excess of the compensation quoted in its proposal. 23. Ownership of Materials. All original drawings, plan documents and other materials prepared by or in possession of Supplier as part of the work or services under these specifications shall become the permanent property of the City, and shall be delivered to the City upon demand. 24. Release of Reports and Information. Any reports, information, data, or other material is given to, prepared by or assembled by Supplier as part of the work or services under these specifications shall be the property of City, and shall not be made available to any individual or organization by Supplier without the prior written approval of the City. 25. Copies of Reports and Information. If the City requests additional copies of reports, drawings, specifications, or any other material in addition to what Supplier is required to furnish in limited quantities as part of the work or services under these specifications, Supplier shall provide such additional copies as are requested, and City shall compensate Supplier for the costs of duplicating of such copies at the Supplier's direct expense. 26. Insurance. Supplier shall procure and maintain for the duration of the Order insurance that is sufficient in scope and amount to permit Supplier to pay in the ordinary course of business against claims for injuries to persons or damages to property that may arise from or in connection with the performance of the work hereunder by Supplier, its agents, representatives, employees or sub-contractors. Supplier will maintain Workers Compensation insurance at statutory levels covering all employees who perform work under this Order. Additional Public Works Construction Purchase Order Terms & Conditions 1. Compensation for Authorized Additional Expenses. To receive compensation for additional expenses outside the scope of the project work, the Supplier shall obtain prior written authoriza-tion from the City to incur those expenses. Compensa-tion for these addition-al expenses shall include time and materials. 2. Payment Terms. The supplier may request one progress payment each month for work satisfactorily completed and accepted by the City. The City shall issue payment within 30 days. The City shall withhold 10 percent of each progress payment as retention to ensure resolution of any stop notices or liens. The City shall release this retention 35 days after filing a notice of completion. 3. Faithful Performance Bond. The supplier shall furnish a surety bond in the amount of 125 percent of the contract price guaranteeing the faithful performance of the contract, including any attorney's fees or other collection costs. 4. Work in the Right-of-Way or on City Property. For work on City managed property, the supplier/ consultant shall obtain a no-fee encroachment permit. A Traffic Control Plan and Water Pollution Control Plan shall be submitted and approved prior to issuance of the permit unless determined by the City not to be required. 5. Prevailing Wage. The supplier and any subcontractors are required to pay prevailing wage and must be registered with the Department of Industrial Relations pursuant to Section 1725.5 of the Labor Code. 6. Insurance. The supplier shall procure and maintain for the duration of the contract insurance against claims for injuries to persons or dam-ages to property which may arise from or in connection with the performance of the work hereunder by the supplier, its agents, representatives, employees or subs. Minimum Scope of Insurance. Coverage shall be at least as broad as: 4 Purchase Order 617251 Proprietary and Confidential a. Insurance Services Office Commercial General Liability coverage (occurrence form CG 20 10 Prior to 1993 or CG 20 10 07 04 with CG 20 37 10 01 or the exact equivalent as determined by the City). b. Insurance Services Office form number CA 0001 (Ed. 1/87) covering Automobile Liability, code 1 (any auto). c. Workers' Compensation insurance as required by the State of California and Employer's Liability Insurance. Minimum Limits of Insurance. The supplier shall maintain limits no less than: a. General Liability: $1,000,000 per occurrence for bodily injury, personal injury and property damage. If Commercial General Liability or other forms with a general aggregate limit is used, either the general aggregate limit shall apply separately to this project/location or the general aggregate limit shall be twice the required occurrence limit. b. Automobile Liability: $1,000,000 per accident for bodily injury and property damage. c. Employer's Liability: $1,000,000 per accident for bodily injury or disease. d. Deductibles and Self-Insured Retentions. Any deductibles or self-insured retentions must be declared to and approved by the City. At the option of the City, either: the insurer shall reduce or eliminate such deductibles or self-insured retentions as respects the City, its officers, officials, employees, and volunteers; or the supplier shall procure a bond guaranteeing payment of losses and related investigations, claim administration and defense expenses. Other Insurance Provisions. The general liability and automobile liability policies are to contain, or be endorsed to contain, the following provi-sions: a. The City, its officers, officials, employees, agents, and volunteers are to be covered as insureds as respects: liability arising out of activities performed by or on behalf of the supplier; products and completed operations of the supplier; premises owned, occupied or used by the supplier; or automobiles owned leased, hired or borrowed by the supplier. The coverage shall contain no special limitations on the scope of protection afforded to the City, its officers, officials, employees, agents or volunteers. b. For any claims related to this project, the supplier's insurance coverage shall be primary insurance as respects the City, its officers, officials, employees, agents, and volunteers. Any insur-ance or self- insurance maintained by the City, its officers, offi-cials, employees, agents or volunteers shall be excess of the supplier's insurance and shall not contribute with it. c. Any failure to comply with reporting or other provisions of the policies including breaches of warranties shall not affect coverage provided to the City, its officers, officials, employees, agents or volunteers. d. The supplier's insurance shall apply separately to each insured against whom claim is made or suit is brought, except with respect to the limits of the insurer's liability. e. Each insurance policy required by this clause shall be endorsed to state that coverage shall not be suspended, voided, canceled by either party, reduced in coverage or in limits except after thirty (30) days' prior written notice by certified mail, return receipt requested, has been given to the City. Acceptability of Insurers. Insurance is to be placed with insurers with a current A.M. Best's rating of no less than A:VII. Verification of Coverage. The supplier shall furnish the City with a certificate of insurance showing required coverage. Original endorse-ments affecting general liability and automobile liability coverage are also required by this clause. The endorsements are to be signed by a person authorized by that insurer to bind coverage on its behalf. All endorsements are to be received and approved by the City before work commences. Subcontractors. The supplier shall include all subcontractors as insured under its policies or shall furnish separate certifi-cates and endorsements for each subcontractor. All coverages for subcontractors shall be subject to all of the requirements stated herein. 5