HomeMy WebLinkAboutItem 5d. Advertise Bids for Groundwater Well Drilling Project and adopt Mitigated Negative Declaration (Spec 2091506) Item 5d
Department: Utilities
Cost Center: 6003
For Agenda of: 3/4/2025
Placement: Consent
Estimated Time: N/A
FROM: Aaron Floyd, Utilities Director
Prepared By: Nick Teague, Water Resources Program Manager
SUBJECT: AUTHORIZATION TO ADVERTISE THE GROUNDWATER WELL
DRILLING PROJECT, SPECIFICATION 2091506, AND ADOPTION OF
THE MITIGATED NEGATIVE DECLARATION AND MITIGATION
MONITORING AND REPORTING PROGRAM FOR THE
GROUNDWATER CONTAMINATION CHARACTERIZATION PROJECT
IMPLEMEN
RECOMMENDATION
1. Approve the project plans and special provisions for the Groundwater Well Drilling
Project, Specification Number 2091506; and
2. Authorize staff to advertise for bids; and
3. Authorize the City Manager to award the Construction Contract pursuant to Section
3.24.190 of the Municipal Code if the lowest responsive and responsible bid is within
the available budget for the Groundwater Well Drilling Project; and
4. Authorize the City Engineer to approve Contract Change Orders up to the available
project budget; and
5. Adopt a Draft Resolution entitled, “A Resolution of the City Council of the City of San
Luis Obispo, California, recommending adoption of the Mitigated Negative Declaration
and Mitigation Monitoring and Reporting Program for the Groundwater Contamination
Characterization Project”; and
6. Authorize the City Manager to approve contract amendments for the project, not to
exceed a cumulative total of $7,750,429.
REPORT IN BRIEF
The Groundwater Well Drilling Project is part of the Implementation Phase of the
Groundwater Contamination Characterization Project, which aims to design and equip
groundwater wells with treatment systems capable of removing tetrachloroethylene
(PCE) contamination, and to put the City’s available groundwater to beneficial use as a
drinking water source while removing PCE contamination from local groundwater
supplies. Implementation will occur in construction phases, with the first phase consisting
of groundwater well drilling. In addition, staff is requesting Council’s authorization for
contract amendments for the project, as described in the fiscal analysis.
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Council’s action also includes consideration of the California Environmental Quality Act
(CEQA) determination for the project as a whole. Staff prepared an Initial Study/Mitigated
Negative Declaration (IS/MND) for the project, which was noticed and circulated for public
review. In addition, tribal consultation was conducted consistent with Assembly Bill 52.
During the public review period, staff received three comment letters on the IS/MND and
conducted additional communications with Native American Tribal representatives.
These comments and recommendations have been addressed and incorporated into the
Final IS/MND. As summarized in this Council Agenda Report and documented in the
IS/MND and findings presented in the Draft Resolution, no new significant impacts were
identified and none of the conditions requiring recirculation of the IS/MND prior to
consideration and adoption have occurred.
POLICY CONTEXT
The Groundwater Well Drilling Project is consistent with the City’s adopted General Plan
Water and Wastewater Element (WWE) Goals A 2.1 and A 3.1 as providing an additional
reliable water supply source helps to ensure a long-term, reliable water supply and
manages the City’s water resources to meet both current and future water demand
associated with development envisioned by the General Plan. Specifically, Policy A 3.2.3
states that “the City will continue to use groundwater to enhance the resiliency of the
City’s water supply portfolio”.
DISCUSSION
Background
Use of available groundwater resources would improve resiliency in the City’s water
supply portfolio. Based on estimates published in the San Luis Obispo Valley Basin
Groundwater Sustainability Plan, the City anticipates about 700 acre-feet of groundwater
is available for use each year. The City does not currently use groundwater as a drinking
water source but considers groundwater as a valuable water resou rce that will help the
City meet its future water supply goals. Local groundwater quality sampling has
documented areas of the San Luis Obispo Valley Groundwater Basin underlying the City
that have localized groundwater contamination from PCE. PCE contamin ation restricts
the City’s use of groundwater as a source of drinking water and must be treated before
the City can utilize this resource. PCE is a chemical that is typically associated with dry
cleaners, textile operations, and metal degreasing activities . The origin of the
contamination remains unknown; however, it is not believed to be from a facility owned
by the City of San Luis Obispo.
In July 2020, the City received a $1,996,575 grant through Round 1 (Planning Phase) of
the State of California Proposition 1 Groundwater Grant Program to study PCE
contamination of the groundwater basin. The State’s program provides funding for grants
and loans for projects that prevent and clean up contamination of groundwater that
serves, or will serve, as a source of drinking water. A detailed understanding of the extent
of PCE contamination and remediation options were necessary steps in fully utilizing the
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City’s ground water supplies. The total Planning Phase cost including the City’s local
match was over $2 million. The Planning Phase of the Groundwater Contamination
Characterization Project, including completion of a Remedial Investigation Report (PCE
Plume Characterization Project Summary), Feasibility Study Report for the PCE Plume
Characterization Project, and submittal of all documentation required by the State Water
Resources Control Board (SWRCB) for reimbursement, was completed April 12, 2023.
In September 2021, staff submitted a conceptual proposal through the Proposition 1
Groundwater Grant Program indicating the City’s interest in additional grant funding for
the Project’s Implementation Phase (Round 3 of the Proposition 1 Groundwater Grant
Program). In April 2022, the SWRCB invited the City to submit a full grant application for
the Implementation Phase of the Groundwater Contamination Characterization Project.
The grant application for the Implementation Phase was submitted July 2022, and the
refined estimated budget was $6,607,850 (Attachment B). On March 13, 2023, staff
received a preliminary grant award letter from the SWRCB in the amount of $5,877,765,
the full amount requested in the grant application (Attachment C). The award of the grant
from the SWRCB required a local match of $730,085.
On August 30, 2023, the City received a memo from the SWRCB that informed the City
that SWRCB waived the match requirement for the City’s Implementation Phase
($730,085; Attachment D). The grant agreement was signed and executed on February
14, 2024, funding the full project budget amount of $6,607,850 with grant funding.
Recommended Action
Staff are currently requesting approval of the project plans and special provisions for, and
the authorizations and approvals needed to commence the Groundwater Well Drilling
Project. The Groundwater Well Drilling Project includes the drilling and construction of a
new groundwater production well along the Bob Jones Trail, about a quarter (0 .25) of a
mile south of the City’s Water Resource Recovery Facility (WRRF). This well will pump
groundwater north, to the future centralized groundwater treatment facility. As previously
mentioned, the Groundwater Well Drilling Project is part of the Implementation Phase of
the Groundwater Contamination Characterization Project, which includes the
Groundwater Well Drilling Project, and two additional Project components: a Monitoring
Well Drilling Project, and a Well Equipping Project. Completion of the projects comprising
the Implementation Phase is expected in Spring 2026, at which time the City will begin
using groundwater as a source of supply.
Staff are requesting authorization for the City Manager to approve contract amendments
for the project, not to exceed a cumulative total of $7,750,429. Previous Council
authorization on May 16, 2023, capped contract amendments for the project at
$7,020,344 ($5,877,765 of grant funding, $1,142,579 City funding). The increase in grant
funding resulting from the local match waiver increased the total available funding for the
project to $7,750,429 ($6,607,850 of grant funding, $1,142,579 City funding). This
authorization will allow staff to utilize the entire available funding amount.
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Previous Council or Advisory Body Action
The City Council authorized staff to prepare and submit a grant application for the
Groundwater Contamination Characterization Project (Round 1 – Planning Phase) on
February 5, 2019.
On December 7, 2021, the City Council approved and authorized specifications for the
Planning Phase of the Groundwater Contamination Characterization Project and award
of the construction contract; staff preparation and submittal of the grant application for the
Implementation Phase (Round 3) of the Project; funding for application preparation and
a local match of a maximum of 10 percent of the total project cost ; execution of grant
application documents; and a Resolution entitled “A Resolution authorizing entering into
a Funding Agreement with the State Water Resources Control Board and authorizing and
designating a representative for Phase 3 of the Groundwater Contamination
Characterization Project.”
On May 16, 2023, the City Council approved and authorized the use of up to $1,142,579
of City funding for the local match requirement (that was required at that time, but later
waived), and any potential increases in costs related to CEQA compliance, construction,
and materials costs and associated inflation; execution of required grant, consultant, and
construction-related agreements; and change orders and contract agreements for the
project, not to exceed a cumulative total of $7,020,344 (including $5,877,765 of grant
funding).
Public Engagement
A public forum was held on December 10, 2024, at the Public Library meeting room. At
the public forum, staff from the City and its consultant presented on this project, and
additional forthcoming projects that will, collectively, result in new infrastructure, which
will provide clean groundwater for use as a new water source for the City. As a result of
the public forum, the Groundwater Contamination Characterization Project was
highlighted in an article by the San Luis Obispo Tribune.
CONCURRENCE
The Utilities Department Deputy Director of Engineering concurs with the proposed scope
and approach of the project.
ENVIRONMENTAL REVIEW
An Initial Study/Mitigated Negative Declaration (IS/MND) was prepared for the “whole of
the action” of the Groundwater Contamination Characterization Project, which includes
the Groundwater Well Drilling Project described in this agenda report and attached
proposed bid package in addition to all other project implementation actions, including but
not limited to construction and operation of monitoring wells, well treatment systems, and
associated utility infrastructure.
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The IS/MND identifies potentially significant impacts to the following environmental
resources: aesthetics, biological resources, cultural resources, geology and soils, noise,
and tribal cultural resources. Mitigation measures are proposed that would reduce all
identified impacts to less-than-significant.
Native American Tribes were notified on July 25, 2024, about the project consistent with
City and State regulations including, but not limited to, Assembly Bill 52. During the
request for consultation window, two responses were received. The Santa Ynez Band of
Chumash Indians contacted the City on August 5, 2024, requesting a consultation
meeting to discuss the project. The City consulted with the Tribe on September 17, 2024,
and shared information regarding the project, the results of the cultural resources survey,
and proposed mitigation measures. The Tribe informed the City that they are in
agreement with the mitigation measures laid out in the public review Draft IS-MND for a
workers environmental awareness program training, archaeological monitoring, and
protocol in the event of unanticipated discoveries. The Salinan Tribe of Monterey
responded on August 30, 2024, requesting notification in the event of a cultural resource
discovery during construction. It is standard City policy to notify local Native American
tribes, including and not limited to the Salinan Tribe of Monterey, in the event of a cultural
resource discovery during construction; in addition, specific language has been added to
CUL-3 requiring notification of Native American tribal representatives. Pursuant to PRC
§21080.3.1 (b) the request for consultation window closed on August 26, 2024. No other
tribal agencies responded to the consultation request during this period.
The IS/MND and Notice of Availability/Notice of Intent (NOA/NOI) to Adopt a Mitigated
Negative Declaration was circulated for public and agency review from December 12,
2024, to January 10, 2025. The IS-MND was submitted to the State Clearinghouse, which
distributed it to affected state agencies. Staff provided the NOA/NOI and IS/MND to
federal and local agencies, Tribes, and interested parties. The environmental notice was
advertised in the New Times, and the document and required notices were posted on the
City’s website and filed with the San Luis Obispo County Clerk and State Office of
Planning and Research.
During the public review period, the City of San Luis Obispo received three comment
letters on the Draft IS-MND from State resource agencies: State Water Resources Control
Board (SWRCB) Division of Drinking Water; California Department of Fish and Wildlife
(CDFW) Central Region 4; and California Department of Transportation (Caltrans). The
Final IS/MND (Attachment E, Reading File) includes these letters, and incorporates
additional information in response to the comments received. These responses are
summarized below.
The SWRCB’s letter describes the agency’s role as a responsible agency and provides
comments recommending additional operational detail be added to the project
description, discussion of granulated activated carbon (GAC) replacement be added to
the hazardous materials evaluation, and discussion of the project’s relationship t o the San
Luis Valley Groundwater Basin be discussed. The Final IS -MND includes additional
details regarding the project’s compliance and consistency with the Groundwater
Sustainability Plan (GSP), operation of the wells and treatment systems, and
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Item 5d
management of the granulated activated carbon (GAC) media. The sustainable
management of the San Luis Valley Basin as described in the GSP includes provisions
for the use of groundwater by the City. As noted in the supplemental project description
details regarding operation and maintenance of the extraction and treatment wells, the
City would comply with the San Luis Obispo Valley Basin Groundwater Sustainability Plan
(GSP) by: implementing an Operations and Maintenance Plan and Monitoring and
Reporting Plan; pumping not more than 600 acre-feet per year (afy), which is less than
the San Luis Valley subarea’s identified groundwater surplus (700 afy); groundwater
quality, groundwater level, and pumping monitoring at the groundwater extraction and
monitoring wells; using telemetry data to automatically adjust pumping rates based on
groundwater levels; and complying with minimum thresholds identified in the GSP to
avoid conditions such as depletion of interconnected surface waters (San Luis Obispo
Creek).
CDFW’s letter describes the agency’s role as a responsible agency and provides
comments and recommendations related to identifying and mitigating the project’s
potential impacts on fish and wildlife resources. While the IS -MND circulated for public
review included and discussed potential impacts to species identified by CDFW, the Final
IS-MND incorporates revisions and additions that respond to CDFW’s comments and
incorporate CDFW’s recommendations, including additional mitigation requirements to
further reduce the project’s potential impacts on western burrowing owl and Crotch’s
bumble bee. The Final IS-MND also addresses CDFW’s comments regarding South-
Central California Coast steelhead. The Final IS-MND includes new and revised language
supporting the determination that the project would have less than significant impacts to
water and riparian resources, including interconnected surface waters and groundwater
dependent ecosystems. As noted above, operation of the project is required to comply
with the GSP and identified thresholds established for undesirable results, such as
depletion of waters in San Luis Obispo Creek; therefore, the project would not create a
condition that results in significant impacts to steelhead. In addition to these comments,
CDFW recommends coordination with CDFW staff prior to groundbreaking activities
onsite or submission of a Lake or Streambed Alteration (LSA) Notification to determine if
the activities proposed within the streams are subject to CDFW’s jurisdiction. The project
does not propose activity within streams, and the City’s required compliance with the GSP
will ensure that the proposed groundwater extractions would not “substantially divert or
obstruct the natural flow of any river, stream, or lake;” therefore, the project does not
include the conditions that would require a LSA.
The letter provided by Caltrans includes a list of the items that would be required as part
of the encroachment permit that the City will request from Caltrans for installation of the
water distribution line within the existing casing under U.S. 101. No specific comments
regarding the Initial Study were provided, and as noted, the City will submit an
encroachment permit application to Caltrans and will comply with the requirements of that
application submittal and permit.
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In addition, the City received additional correspondence from the Santa Ynez Band of
Chumash Indians during the public review period for the IS/MND. The Tribe requested
minor modifications to the language of mitigation measure CUL -1 (Workers
Environmental Awareness Program Training), to include a requirement for a Chumash
Tribal Representative to be present during the training. The Final IS -MND incorporates
this language into CUL-1.
CEQA Guidelines Section 15073.5 describes the requirements for recirculation of an IS-
MND prior to adoption:
a) A lead agency is required to recirculate a negative declaration when the document
must be substantially revised after public notice of its availability has previously
been given pursuant to Section 15072, but prior to its adoption. Notice of
recirculation shall comply with Sections 15072 and 15073.
b) A “substantial revision” of the negative declaration shall mean:
1) A new, avoidable significant effect is identified , and mitigation measures or
project revisions must be added in order to reduce the effect to insignificance,
or
2) The lead agency determines that the proposed mitigation measures or project
revisions will not reduce potential effects to less than significance and new
measures or revisions must be required.
c) Recirculation is not required under the following circumstances:
1) Mitigation measures are replaced with equal or more effective measures
pursuant to Section 15074.1.
2) New project revisions are added in response to written or verbal comments on
the project's effects identified in the proposed negative declaration which are
not new avoidable significant effects.
3) Measures or conditions of project approval are added after circulation of the
negative declaration which are not required by CEQA, which do not create new
significant environmental effects and are not necessary to mitigate an
avoidable significant effect.
4) New information is added to the negative declaration which merely clarifies,
amplifies, or makes insignificant modifications to the negative declaration.
Additional information and mitigation details have been added to the Final IS -MND in
response to the comments and recommendations provided by CDFW and SWRCB.
However, the added and clarified mitigation measures do not create new significant
environmental effects and are not necessary to mitigate an avoidable significant effect.
The new information that has been added to the Final IS-MND clarifies, amplifies, or
makes insignificant modifications to the mitigated negative declaration. Therefore, the
City of San Luis Obispo concludes that the additions and revisions described herein do
not require recirculation of the Draft IS-MND pursuant to CEQA Guidelines Section
15073.5.
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Item 5d
FISCAL IMPACT
Budgeted: Yes Budget Year: 2024-25
Funding Identified: Yes
Fiscal Analysis:
Funding for this project includes $6,607,850 that has been provided through the State
Water Resources Control Board (SWRCB) Proposition 1 Round 3 funds; $1,142,579 from
the City’s Water Fund that was previously allocated to the project by the City Council on
May 16, 2023. Council previously authorized a cumulative total project budget of
$7,020,344 ($5,877,765 of grant funding, $1,142,579 City funding). The increase in grant
funding resulting from the local match waiver increased the available funding to
$7,750,429 ($6,607,850 of grant funding, $1,142,579 City funding).
Table 1. Previously allocated funds and current funding request by funding source.
SWRCB Prop 1
Round 3 Grant
Funding
Water Fund (601)
Unreserved Working Capital
Previously Authorized
Funds
$5,877,765 $1,142,579
Additional Grant Funding $730,085*
Total Funding By Source $6,607,850 $1,142,579
New Total Project Cost $7,750,429
*Amount equal to the initial local match requirement. This funding was added to the total grant
funds following the waiver of the local match.
ALTERNATIVES
Deny the approval to advertise the project. City Council could choose to deny the
authorization to advertise this project. The project is necessary to satisfy the requirements
of the Prop. 1 Groundwater Cleanup grant and failure to advertise this project would result
in non-compliance and potential recoupment of grant funding.
ATTACHMENTS
A - Draft Resolution adopting the Mitigated Negative Declaration and Mitigation
Monitoring and Reporting Program for the Groundwater Contamination
Characterization Project
B - Estimated Budget Submitted with Round 3 Grant Application
C - Prop 1 Round 3 Preliminary Award Letter
D - Revised Memo for Match Waiver and Funding
E - Final Initial Study/Mitigated Negative Declaration and Mitigation Monitoring and
Reporting Program for the Groundwater Contamination Characterization Project
(Reading File)
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RESOLUTION NO. _____ (2025 SERIES)
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF SAN LUIS
OBISPO, CALIFORNIA, ADOPTING THE MITIGATED NEGATIVE
DECLARATION AND MITIGATION MONITORING AND REPORTING
PROGRAM FOR THE GROUNDWATER CONTAMINATION
CHARACTERIZATION PROJECT
WHEREAS, the Groundwater Contamination Characterization Project (Project)
aims to design and equip groundwater wells with treatment systems capable of removing
tetrachloroethylene (PCE) contamination, and to put the City’s available groundwater to
beneficial use as a drinking water source while removing PCE contamination from local
groundwater supplies; and
WHEREAS, the Project is consistent with the City’s adopted General Plan Water
and Wastewater Element because providing an additional reliable water supply source
helps to ensure a long-term, reliable water supply and manage the City’s water resources
to meet both current and future water demand associated with development envisioned
by the General Plan; and
WHEREAS, Native American Tribes were notified on July 25, 2024 about the
project consistent with City and State regulations including, but not limited to, Assembly
Bill 52; and
WHEREAS, an Initial Study/Mitigated Negative Declaration (IS/MND) and Notice
of Availability/Notice of Intent (NOA/NOI) to Adopt a Mitigated Negative Declaration was
prepared for the Groundwater Contamination Characterization Project and circulated for
the mandatory 30-day public and agency review period from December 12, 2024 to
January 10, 2025; and
WHEREAS, the IS/MND was submitted to the State Clearinghouse, who
distributed it to affected state agencies; City staff provided the NOA/NOI and IS/MND to
federal and local agencies, Tribes, and interested parties; the environmental notice was
advertised in the New Times, and the document and required notices were posted on the
City’s website, and filed with the San Luis Obispo County Clerk and State Office of
Planning and Research; and
WHEREAS, the City of San Luis Obispo received three comment letters on the
Draft IS/MND from State resource agencies: State Water Resources Control Board
(SWRCB) Division of Drinking Water; California Department of Fish and Wildlife (CDFW)
Central Region 4; and California Department of Transportation (Caltrans); and
WHEREAS, the City of San Luis Obispo received additional correspondence from
the Santa Ynez Band of Chumash Indians requesting minor modification of a mitigation
measure, which was incorporated into the Final IS/MND, and Northern Chumash Tribal
Council requesting additional information, which was provided; and
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Resolution No. _____ (2025 Series) Page 2
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WHEREAS, the Final IS/MND incorporates additional information and mitigation
details that address received comments, and this information clarifies, amplifies, or makes
insignificant modifications to the mitigated negative declaration.
NOW, THEREFORE, BE IT RESOLVED by the Council of the City of San Luis
Obispo that:
SECTION 1. Environmental Review. Based upon all evidence in the record before
it, including an initial study, the City Council hereby adopts the Final Initial Study–
Mitigated Negative Declaration (IS/MND) prepared and circulated for this Project, and
adopts all of the findings related to the Project:
a) The Groundwater Contamination Characterization Project IS /MND was
prepared and circulated for public review in accordance with the California
Environmental Quality Act (CEQA) and the State CEQA Guidelines. It reflects
the lead agency’s independent judgement and analysis, and it adequately
addresses potential environmental impacts associated with the proposed
Project; and
b) There is no substantial evidence that the Project will have a significant effect
on the environment as mitigated in accordance with the measures identified in
the IS/MND; and
c) Additional information and mitigation details have been added to the Final
IS/MND in response to the comments and recommendations provided in
response to the IS/MND. The added mitigation measures do not create new
significant environmental effects and are not necessary to mitigate an
avoidable significant effect. The new information that has been added to the
Final IS/MND clarifies, amplifies, or makes insignificant modifications to the
IS/MND. Therefore, the additions and revisions do not require recirculation of
the Draft IS-MND pursuant to CEQA Guidelines Section 15073.5 , as:
1) Mitigation measures are replaced with equal or more effective measures
pursuant to CEQA Guidelines Section 15074.1.
2) New project revisions have been added in response to written or verbal
comments on the project's effects identified in the proposed negative
declaration which are not new avoidable significant effects.
3) Mitigation measures have been added that do not create new significant
environmental effects.
4) New information has been added, which merely clarifies, amplifies, or
makes insignificant modifications to the IS/MND.
d) All potentially significant environmental effects were analyzed adequately in the
Final IS/MND IS/MND for the Groundwater Contamination Characterization
Project, subject to the following mitigation measures being incorporated into
the Project and subject to the mitigation monitoring program in the Final
IS/MND, which is hereby adopted:
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Resolution No. _____ (2025 Series) Page 3
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AESTHETICS
AES-1 Nighttime Work Requirements
In the event nighttime work is necessary during the project construction phase, any
portable lighting shall be shielded and/or directed away from adjacent properties. Night
lighting for construction activities shall be the minim um necessary to ensure safety and
security for nighttime activities and operations. Lighting at the project site shall consist of
light-emitting diode lights in all areas where nighttime construction activities will occur and
be either motion-activated or use timers to ensure safety and security and reduce the
impact of additional light pollution at night. The City shall verify compliance with the
construction night lighting requirements via an inspection during nighttime construction
activities.
AIR QUALITY
AQ -1 Odor Reduction
Where construction activities occur within 50 feet of a sensitive receptor, the construction
contractor shall implement the following additional idling restrictions, which shall be
shown on grading and construction plans:
Idling Restrictions Near Sensitive Receptors for Both On- and Off-Road Equipment
Staging and queuing areas shall be located at the greatest distance feasible from
sensitive receptor locations;
Diesel idling while equipment is not in use is not permitted;
Use of alternative-fueled equipment is recommended whenever possible; and
Signs that specify the no-idling requirements shall be posted and enforced at the
construction site.
The City Utilities Department shall verify these measures are located on construction
plans prior to the start of construction. Once during construction, City Inspector shall visit
the project site to verify these idling restrictions have been implemented.
BIOLOGICAL RESOURCES
BIO-1 Worker Environmental Awareness Program
Prior to initiation of construction activities at the treatment well site, all personnel
associated with project construction shall attend a Worker Environmental Awareness
Program (WEAP) training, conducted by a qualified biologist, to aid workers in recognizing
special-status species and nesting birds that may occur within the project site. The
specifics of this program shall include identification of special-status species with potential
to occur, a description of their regulatory status and habitat requirements, general
ecological characteristics of any other sensitive resources, and a review of the limits of
construction and measures required to avoid and/or reduce impacts to biological
resources within the project site. A fact sheet conveying this information shall also be
prepared for distribution to the construction contractor. All employees shall sign a form
provided by the biologist indicating they have attended the WEAP training and understand
the information presented to them. The construction foreman shall ensure crew members
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are aware of project boundaries and adhere to the mitigation measures designed to avoid
or minimize effects to listed species, nesting birds, and other special-status species.
BIO-2 Pre-Construction Survey for Special-Status Wildlife Species
A qualified biologist shall conduct a pre-construction survey of the treatment well site and
adjacent habitat no more than two weeks prior to the start of construction at the treatment
well site. The biologist shall document the presenc e or absence of any special-status
wildlife species with potential to occur within the treatment well site plus a 50 -foot buffer.
The pre-construction survey shall include surveys for burrowing owl that follow the
“Burrowing Owl Survey Protocol and Mitigation Guidelines” (California Burrowing Owl
Consortium [CBOC] 1993) and CDFW’s “Staff Report on Burrowing Owl Mitigation”
(California Department of Fish and Game [CDFG] 2012) within areas of suitable habitat
during the survey season immediately prior to construction.
If special-status species are observed onsite during the pre-construction surveys, they
shall be allowed time to leave or be relocated prior to the initiation of construction
activities. If special-status species are present during construction activities, they shall be
handled in accordance with Mitigation Measure BIO-7.
BIO-3 Burrowing Owl Buffers
If burrows known to be currently or previously occupied by burrowing owl are found, either
during surveys or project activities, a 500-meter no-disturbance buffer shall be
established around each burrow.
BIO-4 Burrowing Owl Take Authorization
If burrowing owl individuals or burrows known to be currently or previously occupied by
burrowing owl are found, either during surveys or project activitie s, the City of San Luis
Obispo shall consult with CDFW to discuss how to implement the project and avoid take.
If avoidance is not feasible, acquisition of a State Incidental Take Permit pursuant to
California Fish and Game Code Section 2081 subdivision (b), prior to any ground
disturbing activities, shall be required in order to comply with the California Endangered
Species Act.
BIO-5 Crotch’s Bumble Bee Habitat Assessment and Surveys
A qualified biologist shall conduct a habitat assessment to determine if the project area
and the immediate surrounding vicinity contain habitat suitable to support Crotch’s
bumble bee. The assessment shall document potential nesting sites, which include all
small mammal burrows, perennial bunch grasses, thatched annual gras ses, brush piles,
old bird nests, dead trees, and hollow logs.
If potentially suitable habitat for Crotch’s bumble bee is identified in the habitat
assessment, the qualified biologist shall conduct focused surveys for Crotch’s bumble
bee and their requisite habitat features, following the methodology outlined in the Survey
Considerations for California Endangered Species Act Candidate Bumble Bee Species
(CDFW 2023).
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BIO-6 Crotch’s Bumble Bee Buffers and Take Authorization
If Crotch’s bumble bee is detected during the required habitat assessment and surveys,
all small mammal burrows and thatched/bunch grasses shall be avoided by a minimum
of 50 feet to avoid take of Crotch’s bumble bee. If ground -disturbing activities would occur
during the overwintering period (October through February), the City of San Luis Obispo
shall consult with CDFW to discuss how to implement project activities and avoid take.
Any detection of Crotch’s bumble bee prior to or during project implementation warrants
consultation with CDFW to discuss how to avoid take.
If avoidance is not feasible, acquisition of a State Incidental Take Permit pursuant to
California Fish and Game Code Section 2081 subdivision (b), prior to any ground
disturbing activities, would be required in order to comply with the California Endangered
Species Act.
BIO-7 Biological Monitoring and Special-Status Species Relocation
A qualified biologist shall be onsite at the treatment well site during all vegetation removal,
initial ground disturbing activities, and/or during any construction activities that may
impact sensitive biological resources. If the biologist discovers special-status animal
species on the project site, the biologist shall have the authority to temporarily halt or
redirect work to avoid potential impacts. If avoidance is not feasible, the biologist shall be
responsible for relocating wildlife species out of the treatment well site in accordance with
the requirements of applicable regulatory agencies, such as CDFW or the United States
Fish and Wildlife Service. Special-status wildlife shall not be handled without prior
permission from the necessary regulatory agencies. Species-specific monitoring
requirements may be superseded or added to by resource agency permits and/or
incidental take authorizations. Following the relocation of wildlife, the biologist shall
submit a report to the City confirming the methodology and results of relocating the
wildlife.
BIO-8 Nesting Bird Surveys
A preconstruction nesting bird survey shall be conducted by a qualified biologist no more
than 14 days prior to initiation of project construction activities. The survey shall be
conducted within the treatment well site and include a 50 -foot buffer for passerines and a
500-foot buffer for raptors. The survey shall be conducted by a biologist familiar with the
identification of avian species known to occur in the region and shall focus on trees,
vegetated areas, and other potential nesting within the vicinity of the treatment well site.
If active nests are identified in the survey, an appropriate avoidance buffer (typically 50
feet for passerine species and 500 feet for raptors) shall be determined and demarcated
by the biologist with high visibility material located within or adjacent to the treatment well
site. All project personnel shall be notified as to the existence of the buffer zones and to
avoid entering buffer zones during the nesting season. No project construction activities
shall occur within the buffer until the biologist has confirmed that breeding/nesti ng is
complete, and the young have fledged the nest. Encroachment into the buffer shall occur
only at the discretion of the qualified biologist.
Page 105 of 717
Resolution No. _____ (2025 Series) Page 6
R ______
CULTURAL RESOURCES
CUL-1 Workers Environmental Awareness Program Training
All construction personnel and monitors who are not trained archaeologists shall be
briefed regarding unanticipated discoveries prior to the start of construction activities. A
basic presentation shall be prepared and presented by a qualified archaeologist and
Chumash Tribal Representative to inform all personnel working on the project about the
archaeological sensitivity of the area. The purpose of the WEAP training is to provide
specific details on the kinds of archaeological materials that may be identified during
construction of the project and explain the importance of and legal basis for the protection
of significant archaeological resources. Each worker shall also learn the proper
procedures to follow in the event that archaeological resources or human remains are
uncovered during ground-disturbing activities. These procedures include work curtailment
or redirection, and the immediate contact of the on -call archaeologist and Native
American representative. The necessity of training attendance shall be stated on all
construction plans and the City of San Luis Obispo shall maintain records demonstrating
construction worker WEAP participation.
CUL-2 Archaeological and Native American Monitoring
Prior to any ground disturbing activities, the project proponent shall retain an
archaeologist meeting the Secretary of the Interior’s Qualifications Standards (NPS 1983)
(Qualified Archaeologist) to oversee the implementation of this measure.
Prior to any ground disturbing activities, the archaeologist shall provide a Cultural
Resources Mitigation and Monitoring Plan (CRMMP) for review and approval by the City
of San Luis Obispo. The CRMMP should include, but not be limited to, the following:
a. A list of personnel involved in the monitoring activities;
b. Description of Native American involvement;
c. Description of how the monitoring shall occur;
d. Description of location and frequency of monitoring (e.g., full time, part time, spot
checking);
e. Description of what resources may be encountered;
f. Description of circumstances that would result in the halting of work at the project
site;
g. Description of procedures for halting work on the site and notification procedures;
h. Description of monitoring reporting procedures; and
i. Provide specific, detailed protocols for what to do in the event of the discovery of
human remains.
The Qualified Archaeologist shall provide conditional monitoring as well as on call
response in the case of an inadvertent discovery of archaeological resources. Given the
developed nature of monitoring well locations MW -01 through MW -08 and MW -10
through MW -12, and the method of construction activities proposed (i.e., drilling),
Page 106 of 717
Resolution No. _____ (2025 Series) Page 7
R ______
monitoring at these locations should be limited to spot-checking and periodic examination
of soils through selective sampling of soils brought to the surface as a result of the dri lling
activities. All construction-related ground disturbances, including clearing/grubbing and
drilling, within the treatment well site, west and east of U.S. 101) and west of San Luis
Obispo Creek be monitored by an archaeologist and a Native American re presentative.
In general, archaeological, and Native American monitoring shall be limited to initial
ground disturbance, which is defined as construction-related earthmoving of sediments
from their native place of deposition and does not include any second ary movement of
sediment that might be required for the project. The Qualified Archaeologist may adjust
monitoring efforts as needed (increase, decrease, or discontinue monitoring frequency)
based on the observed potential for construction activities to en counter archaeological
deposits. The Qualified Archaeologist shall be responsible for maintaining daily
monitoring logs.
Throughout the course of project construction activities, if a discovery is made by
construction personnel and a monitor is not presen t, the protocols and procedures
outlined in the Mitigation Measure CUL-3, Unanticipated Discovery of Archaeological
Resources, shall be followed. Following the completion of construction, the Qualified
Archaeologist shall prepare an archaeological monitoring report for submittal to the City
and the CCIC with the results of the archaeological monitoring program.
CUL-3 Unanticipated Discovery of Archaeological Resources
In the event that archaeological remains are encountered during construction, City staff
shall be notified and all work within 50 feet of the find shall be halted until the find is
evaluated by the Qualified Archaeologist or other designated archaeologist working under
the direction of the Qualified Archaeologist and appropriate mitigation, if necessary, is
implemented. Native American tribal representatives shall be notified. If archaeological
remains are identified, the resource shall be evaluated for significance under City
Archaeological Resource Preservation Program Guidelines, and further treatment
measures, including but not limited to avoidance consistent with City General Plan
Policies, Phase 2 Subsurface Archaeological Resource Evaluation, or Phase 3
Archaeological Data Recovery Excavation may be required. Work within 50 feet of the
find shall not resume until authorization is received from the City. This measure shall be
included on all construction plans.
GEOLOGY AND SOILS
GEO-1 Unanticipated Discovery of Paleontological Resources
In the event of a fossil discovery by construction personnel at the treatment well site, the
construction contractor shall halt all construction activities within the 50 feet of the fossil,
and a Qualified Professional Paleontologist shall be retained to e valuate the find prior to
resuming construction activity. If it is determined the fossil(s) is (are) scientifically
significant, the Qualified Professional Paleontologist shall complete the following
conditions to mitigate impacts to significant fossil resources:
Fossil Salvage. If fossils are discovered, the Qualified Professional Paleontologist
shall have the authority to halt or temporarily divert construction equipment within
Page 107 of 717
Resolution No. _____ (2025 Series) Page 8
R ______
50 feet of the find until the Qualified Professional Paleontologist evaluate the
discovery and determine if the fossil may be considered significant. Bulk matrix
sampling may be necessary to recover small invertebrates or microvertebrates
from within paleontologically sensitive deposits.
Fossil Preparation and Curation. Once salvaged, significant fossils shall be
identified to the lowest possible taxonomic level, prepared to a curation -ready
condition, and curated in a scientific institution with a permanent paleontological
collection along with all pertinent field notes, photos, d ata, and maps. Fossils of
undetermined significance at the time of collection may also warrant curation at
the discretion of the Qualified Professional Paleontologist.
Final Paleontological Report. The Qualified Professional Paleontologist shall
submit a report describing the results of the paleontological monitoring efforts
associated with the project. The report shall include a summary of the field and
laboratory methods, an overview of the project geology and paleontology, a list of
taxa recovered (if any), an analysis of fossils recovered (if any) and their scientific
significance, and recommendations. The report shall be submitted to the City.
NOISE
N-1 Noise Reducing Best Management Practices
During monitoring well installation at MW -01, MW -02, MW -03, MW -06, and MW -10, the
following construction noise best management practices shall be adhered to:
Stationary construction equipment that generates noise that exceeds 60 dBA shall
be shielded with the most modern noise control devices (i.e. mufflers, lagging,
and/or motor enclosures).
Impact tools (e.g., drills) used for project construction shall be h ydraulically or
electrically powered wherever possible to avoid noise associated with
compressed-air exhaust from pneumatically powered tools.
Where use of pneumatic tools is unavoidable, an exhaust muffler on the
compressed-air exhaust shall be used.
All construction equipment shall have the manufacturers’ recommended noise
abatement methods installed, such as mufflers, engine enclosures, and engine
vibration insulators, intact and operational.
All construction equipment shall undergo inspection at periodic intervals to ensure
proper maintenance and presence of noise control devices (e.g., mufflers,
shrouding, etc.).
At least 21 days prior to the start of construction, notify off -site businesses and
residents within 150 feet of construction of planned c onstruction activities. The
notification shall provide brief description of the project, activities that would occur,
hours of construction, the duration of construction, and a phone number to the City
Community Development Department for the public to direct noise-related
complaints.
Page 108 of 717
Resolution No. _____ (2025 Series) Page 9
R ______
N-2 City Approval and Personnel Briefing
Construction plans shall note construction hours, truck routes, and all construction noise
best management practices, and shall be reviewed and approved by the City Utilities
Department prior to advertisement of the construction request for bids. All construction
workers shall be briefed at a preconstruction meeting on construction hour limitations and
how, why, and where best management practices are to be implemented.
TRIBAL CULTURAL RESOURCES
Implement Mitigation Measures CUL-1, CUL-2, and CUL-3.
Upon motion of Council Member ___________, seconded by Council Member
___________, and on the following roll call vote:
AYES:
NOES:
ABSENT:
The foregoing resolution was adopted this _____ day of _______________ 2025.
___________________________
Mayor Erica A. Stewart
ATTEST:
______________________
Teresa Purrington
City Clerk
APPROVED AS TO FORM:
______________________
J. Christine Dietrick
City Attorney
IN WITNESS WHEREOF, I have hereunto set my hand and affixed the official seal of the
City of San Luis Obispo, California, on ______________________.
___________________________
Teresa Purrington
City Clerk
Page 109 of 717
Page 110 of 717
Attachment 7 - Budget Tables Proposition 1 GWGP Implementation Full Proposal
Applicant: City of San Luis Obispo FAAST PIN: 48368
Project: City of San Luis Obispo PCE Plume Characterization
Requested Grant Local Match Other Funding Total % Local Match
1. Direct Project Administration Costs $114,480 $12,720 $0 $127,200 10%
1.1 Program Management Administration $87,480 $9,720 $97,200 10%
1.2 City Staff Administration $27,000 $3,000 $30,000 10%
2. Planning/Design/Engineering/Environmental $588,690 $142,410 $0 $731,100 17%
2.1 Groundwater Model $117,000 $13,000 $130,000 10%
2.2 Develop Extraction and Monitoring Plan $28,800 $3,200 $32,000 10%
2.3 Design Monitoring Wells $66,420 $7,380 $73,800 10%
2.4 Design Extraction and Treatment Wells (two
locations)$376,470 $41,830 $418,300 10%
2.5 Permitting $0 $77,000 $77,000 100%
3. Construction/Implementation $5,108,670 $567,630 $0 $5,676,300 10%
3.1 Construction - Monitoring Well(s)$830,250 $92,250 $922,500 10%
3.2 Construction Administration - Monitoring Well(s)$99,630 $11,070 $110,700 10%
3.3 Construction - Extraction and Treatment Wells
(two locations)$3,764,700 $418,300 $4,183,000 10%
3.4 Construction Administration Extraction and
Treatment Well $414,090 $46,010 $460,100 10%
4. Monitoring/Performance $36,000 $4,000 $0 $40,000 10%
4.1 Continued Sampling and Monitoring $36,000 $4,000 $40,000 10%
5. Outreach $29,925 $3,325 $0 $33,250 10%
5.1 Outreach $19,800 $2,200 $22,000 10%
5.2 Technical Advisory Meetings $10,125 $1,125 $11,250 10%
Grand Total:$5,877,765 $730,085 $0 $6,607,850 11%
Other Funding Sources:
Note: CHECK YOUR NUMBERS! Do NOT assume this Excel spreadsheet is correct. Please refer to the READ ME tab.
Does the Budget Summary Total match the Budget Details Total?YES
Prop 1 GROUNDWATER GRANT PROGRAM - BUDGET SUMMARY
Page 111 of 717
Attachment 10 - Budget Tables Proposition 1 GWGP Implementation Full Proposal
Project: City of San Luis Obispo PCE Plume Characterization
1. Direct Project Administration Costs 1.9%$127,200
1.1 Program Management Administration Refer to Budget Narrative $0 $97,200.00 LS 1 $97,200 $97,200
1.2 City Staff Administration City Staff $100.00 300 $30,000 $0 $30,000
2. Planning/Design/Engineering/Environmental 10.7%$731,100
2.1 Groundwater Model Refer to Budget Narrative $0 $130,000.00 LS 1 $130,000 $130,000
2.2 Develop Extraction and Monitoring Plan Refer to Budget Narrative $0 $32,000.00 LS 1 $32,000 $32,000
2.3 Design Monitoring Wells Refer to Budget Narrative $0 $6,150.00 EA 12 $73,800 $73,800
2.4 Design Extraction and Treatment Wells (two
locations)Refer to Budget Narrative $0 $209,150.00 EA 2 $418,300 $418,300
2.5 Permitting Refer to Budget Narrative $0 $77,000.00 LS 1 $77,000 $77,000
3. Construction/Implementation 85.8%$5,676,300
3.1 Construction - Monitoring Well(s)Refer to Budget Narrative $0 $76,875 EA 12 $922,500 $922,500
3.2 Construction Administration - Monitoring
Well(s)Refer to Budget Narrative $0 $110,700 LS 1 $110,700 $110,700
3.3 Construction - Extraction and Treatment Wells
(two locations)Refer to Budget Narrative $0 $2,091,500 EA 2 $4,183,000 $4,183,000
3.4 Construction Administration Extraction and
Treatment Well Refer to Budget Narrative $0 $460,100 LS 1 $460,100 $460,100
4. Monitoring/Performance 1.2%$40,000
4.1 Continued Sampling and Monitoring Refer to Budget Narrative $0 $40,000 LS 1 $40,000 $40,000
5. Outreach 0.4%$33,250
5.1 Outreach Refer to Budget Narrative $0 $22,000 LS 1 $22,000 $22,000
5.2 Technical Advisory Meetings Refer to Budget Narrative $0 $11,250 LS 1 $11,250 $11,250
Grand Total:100%$6,607,850
Note: CHECK YOUR NUMBERS! Do NOT assume this Excel spreadsheet is correct. Please refer to the READ ME tab.
Does the Budget Summary Total match the Budget Details Total?YES
Discipline/Consultant/
Description
Prop 1 GROUNDWATER GRANT PROGRAM - BUDGET DETAIL
Applicant: City of San Luis Obispo FAAST PIN: 48368
# of
Units Total CostRate# of
Hours
Total
Labor
Percent of
CostBudget Category TOTALS
Consulting/Materials/Equipment
Unit Cost Units
Labor Costs
Page 112 of 717
Attachment 10 - Budget Tables Proposition 1 GWGP Implementation Full Proposal
Project: City of San Luis Obispo PCE Plume Characterization
Prop 1 GROUNDWATER GRANT PROGRAM - BUDGET NARRATIVE
Applicant: City of San Luis Obispo FAAST PIN: 48368
Costs associated with work with contracts to be awarded are based on professional experience and the latest program cost estimates. Note that consultant costs will be
completed on a time and materials basis and construction contractor costs will be paid based on bid documents and percent progress. The basis for each line item estimate in
the budget is described below.
1. Direct Project Administration Costs
1.1 Program Management Administration -Estimated at 1.5% of the overall program value.
1.2 City Staff Administration -Based on City staff availability and expected level of effort/involvement to provide general oversight on behalf of the City,manage consultants,
execute and manage City contracts. Budget assumes 300 hours of staff time at an hourly rate of $100/hr.
2. Planning/Design/Engineering/Environmental
2.1 Groundwater Model -Estimated based on experience and engineering judgement. Work anticipated to be performed by Water Systems Consulting Team.
2.2 Extraction and Monitoring Plan -Estimated based on experience and engineering judgement. Work anticipated to be performed by Water Systems Consulting Team.
2.3 Design Monitoring Wells -Estimated at 8% of the total construction cost of Task 3.1. Work anticipated to be performed by Water Systems Consulting Team.
2.4 Design Extraction and Treatment Wells (two locations) -Estimated at 10% of the total construction cost of Task 3.3. Work anticipated to be performed by Water Systems
Consulting Team.
2.5 Permitting -Estimated at 1.5% of the total construction cost of Task 3.1 and 3.3. Work anticipated to be performed by Water Systems Consulting Team and a City selected
environmental consultant. Assumes an IS/MND will be required prior to construction of the extraction wells.
3. Construction and Implementation
3.1 Monitoring Well Construction -Estimated construction cost is based on applying recent bidding information and applying engineering judgment for the construction of up to
12 monitoring wells (8 minimum). Costs based on sonic drilling method, and include permitting, traffic control, sound walls, waste disposal, drilling, construction, and well
development.
3.2 Monitoring Well Administration -Estimated at 12% of the total construction cost of Task 3.1, which includes monitoring well inspection, final design of well screening, and
general construction administration. Work anticipated to be performed by Water Systems Consulting Team.
3.3 Extraction and Treatment Well Construction -Estimated construction cost is based on amalgamating different cost estimating methods, including reviewing recent bidding
information, coordinating with suppliers and applying engineering judgement. Construction cost also escalated based on inflation rate of 3% average year over year to mid-2025,
which is the anticipated construction period. Construction anticipated to be awarded to two (2) independent construction contractors. One contractor will drill the well(s) and
another contractor will equip and install the treatment systems. Assumes the wells can be located on City owned property.
3.4 Extraction and Treatment Well Construction Administration -Estimated at 11% of the total construction costs of Task 3.3. Work anticipated to be performed by Water
Systems Consulting Team.
4. Monitoring and Performance
4.1 Monitoring and Performance -Includes field sampling and laboratory testing for the 12 monitoring wells (8 minimum) twice per year and includes preparation of summary
report. Budget estimate includes sampling for one year following construction.
5. Outreach
5.1 Outreach -Costs associated with this task were estimated using another project's estimated costs for similar work.
5.2 Technical Advisory Meetings -Budget based on attendance of six (6) 2-hour meetings and preparing materials for meeting
Page 113 of 717
Page 114 of 717
State Water Resources Control Board
March 6, 2023
Mr. Aaron Floyd
City of San Luis Obispo
Utilities Department
879 Morro Street
San Luis Obispo, CA 93401
afloyd@slocity.org
PROPOSITION 1 GROUNDWATER GRANT PROGRAM (GWGP) ROUND 3
IMPLEMENTATION GRANT SOLICITATION, NOTIFICATION OF AWARD
Dear Mr. Floyd:
Congratulations! The Tetrachloroethylene (PCE) Plume Characterization
Implementation Project (Project) has been approved for funding with a grant award of
$5,877,765.
The Project consists of preparing a fate and transport groundwater model of the PCE
plume, siting and construction of 2 extraction and treatment wells, and installation of a
minimum of 8 monitoring wells to monitor the long-term progress of treatment within the
City of San Luis Obispo (City).
The Project has been reviewed by technical experts from the State Water Resources
Control Board’s (State Water Board) Division of Financial Assistance (Division), the
Central Coast Regional Water Quality Control Board, and the State Water Board’s
Division of Drinking Water. The technical experts concur that the Project, as proposed,
should achieve the stated objectives and is eligible for funding per the GWGP
Guidelines, as amended on February 2, 2021.
Based on staff’s review of the City’s request for a reduced match, supporting information
provided in the Full Proposal, and the GWGP Guidelines, Table 2, the City qualifies for a
reduced match of eleven percent (11%) because one hundred percent (100%) of the
Project benefits a Disadvantaged Community or Economically Distressed Area.
Robin Guillot has been assigned as the Project Manager for this Project. You will
receive an introductory email from an assigned Program Analyst with further information
about roles and responsibilities, grant agreement development, invoicing, deliverables,
performance measures, and reporting requirements. You will also be contacted by your
assigned Project Manager to ensure that all conditions and comments are addressed
Page 115 of 717
Mr. Floyd - 2 -
prior to execution of the final grant agreement. We encourage your prompt response to
any requests from our staff because unreasonable delays or failure to respond could
result in withdrawal of this grant award.
Your grant award is conditioned on the successful negotiation of a grant agreement .
The agreement process will begin with the finalization of a scope of work and budget
that is acceptable to the Division. The scope of work will be based on the Full Proposal;
however, the Division may require changes to the scope of work and budget as part of
the grant agreement negotiation process. Based on the technical review of the Full
Proposal, staff have initially identified the following item(s) that will need to be
addressed.
Key information to be provided prior to execution of the grant agreement:
1. Additional documentation regarding monitoring requirements and a detailed
description of the remediation technology intended to be used for the Project.
2. Documents omitted from the Full Proposal including an up-to-date Project
Director Certification form signed by the City’s Authorized Representative.
Thank you for your consideration in addressing these items with Division staff. We look
forward to working with you on this Project. Please contact the assigned Project
Manager, Robin Guillot, with any questions at (916) 319-8259, or
Robin.Guillot@waterboards.ca.gov.
Sincerely,
Joe Karkoski, Deputy Director
Division of Financial Assistance
cc: see next page
Joe Karkoski Digitally signed by Joe Karkoski
Date: 2023.03.06 10:48:31
-08'00'
Page 116 of 717
Mr. Floyd - 3 -
cc: Christopher Stevens
Division of Financial Assistance
Kim Dinh
Division of Financial Assistance
Alex Huang
Division of Financial Assistance
Robin Guillot
Division of Financial Assistance
Debbie Cheung
Division of Financial Assistance
Andrew Nevis
Office of Legislative Affairs
Jeff Densmore
Division of Drinking Water
Katie McNeill
Regional Water Quality Control Board
Dean Thomas
Regional Water Quality Control Board
Daniel Ellis
Regional Water Quality Control Board
Miguel Barcenas
City of San Luis Obispo
mbarcena@slocity.org
Page 117 of 717
Page 118 of 717
State Water Resources Control Board
TO:
FROM:
DATE:
Joe Karkoski
Deputy Director
DIVISION OF FINANCIAL ASSISTANCE
Alex Huang
Senior Engineering Geologist
DIVISION OF FINANCIAL ASSISTANCE
August 29, 2023
SUBJECT: REVISED - PROPOSITION 1 GROUNDWATER GRANT PROGRAM
(GWGP) ROUND 3 FUNDING RECOMMENDATIONS
BACKGROUND
The GWGP Round 3 full proposal solicitation window opened on April 14, 2022 , and
closed on July 15, 2022. Technical reviewers from several state agencies scored each
proposal according to the rubric in Appendix F of the GWGP guidelines. On
February 9, 2023, the Deputy Director of the Division of Financial Assistance (DFA)
approved staff’s recommendation to award funding for eight projects and to not award
funding for the Central Coast Blue project (Attachment A). DFA issued funding award
letters for the eight Round 3 projects approved for funding. On March 17, 2023, DFA
issued a funding denial letter for the Central Coast Blue project (Attachment B).
The following new developments occurred after the Deputy Director of DFA approved
staff’s recommendation:
1.DFA received an urgent appeal letter from the City of Pismo Beach (City)
regarding the funding determination for the Central Coast Blue project on
March 23, 2023 (Attachment C). Staff met with the City in person on
April 5, 2023, and again via Teams on April 25, 2023, to discuss the project and
its nexus to the cleanup or prevention of groundwater contamination. The City
initially asked for $35.7 million in its proposal, then reduced the request to
$18.5 million in its appeal letter. Most recently, in an email dated May 24, 2023,
the City asked DFA to reconsider an approval of $8 million in GWGP funding
(Attachment D).
2.The GWGP Guidelines were amended on May 2, 2023, to allow the Deputy
Director of DFA discretion to completely waive the match requirements for Round
3 projects that benefit disadvantaged communities (DACs) and severely
disadvantaged communities (SDACs), to the extent authorized by statute.
Page 119 of 717
Joe Karkoski - 2 -
ANALYSIS: REVISED FUNDING RECOMMENDATION FOR CITY OF PISMO
BEACH’S CENTRAL COAST BLUE PROJECT
DFA staff have re-evaluated the City’s proposed Central Coast Blue project (Project)
and concluded that the Project is eligible for GWGP funding, and recommend providing
$8 million in Prop 1 GWGP funding.
By statute, projects that prevent contamination of groundwater that has served, or
serves, as a source of drinking water are eligible. (Wat. Code, § 79771.) This project
would prevent groundwater contamination that has served, and serves, as a source of
drinking water by providing groundwater recharge to protect against contamination.
Under the GWGP Guidelines, projects that provide groundwater recharge to prevent or
reduce contamination of municipal or domestic wells, or that consist of groundwater
injection to prevent seawater intrusion, are specifically listed as eligible project types.
(GWGP Guidelines, § 4.4, subds. d and e.) Although the available information indicates
that the communities’ voluntarily reduced pumping has reduced the likelihood of
seawater intrusion, seawater intrusion would cause substantial adverse impacts to this
water supply. Based on the eligibility criteria in the statute and GWGP Guidelines, the
Project is eligible.
Staff have determined that $8 million in funding is appropriate, but not the full requested
amount of $35.7 million, based on the following considerations . The City and other local
governments have successfully forestalled the immediate threat of groundwater
degradation because the City and its partner agencies have diligently conserved water
and reduced their groundwater pumping rates. As a result, the Project scored lower
than the other proposals evaluated for Prop 1 GWGP funding. As discussed in the next
section, there are insufficient remaining Prop 1 GWGP funds to cover the entire
$35.7 million request.
However, DFA staff have determined that the benefits of the project are significant
enough to justify a GWGP grant. Future precipitation is unpredictable. During critically
dry years, dwindling surface water supplies may force the City and other local
governments to increase pumping rates, resulting in overdraft of the groundwater basin.
The Project aims to prevent situations like this from happening. Additionally, the
potential for the Project to enhance local water supply reliability and address the urgent
need for an alternative water supply cannot be overlooked. The Project supports the
priorities of Proposition 1 by enhancing water supply reliability (Wat. Code, §
79771(b)(3)), promoting groundwater recharge (Wat. Code, § 79771(b)(4)), and by
allowing California to adapt to changing hydrologic conditions brought on by climate
change (Wat. Code, § 79770). The project also aligns with California’s Water Supply
Strategy and conforms with Executive Order N-3-23.
Therefore, staff recommend providing $8 million in Prop 1 GWGP funding for the
Central Coast Blue Project.
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Joe Karkoski - 3 -
ANALYSIS: MATCH WAIVERS
The Prop 1 GWGP Guidelines set aside funds for projects benefiting DACs and SDACs
as required by statute. The rest of the funds may be used for any projects eligible for
Prop 1 GWGP, regardless of disadvantaged status (generic funds). The set-aside funds
for projects benefitting DACs were exhausted after the initial award of Round 3 projects,
and only one Round 3 project benefits an SDAC. Waiving the match requirement for
eligible Round 3 projects would enable the GWGP to commit an additional $6.2 million
from the generic funds and $1 million from the SDAC set-aside funds.
CONCLUSIONS
If the Deputy Director of DFA approves the $8 million request from the City and waives
the match requirement for all eligible Round 3 DAC and SDAC projects, there would be
$13.3 million remaining in generic funds, and $20.8 million left in the SDAC set-aside.
These funds may be used to fund additional cost increases for existing projects, or to
fund new drinking water treatment or wastewater projects that serve SDACs.
STAFF RECOMMENDATIONS
Staff recommends the following:
1. Award GWGP funds for the Central Coast Blue Project and waive match for all
Round 3 projects that serve DACs and an SDAC that are eligible for the match
waiver (a total of five projects) as shown in Table 1. One DAC project would not
qualify for match waiver, as explained in the footnote. The non-DAC projects do not
qualify for a match waiver under the amended Guidelines .
$635,900,000
$20,800,000 $13,300,000
Prop 1 GWGP Funds Remaining After
Waiving Match and Funding Central
Coast Blue
Committed SDAC Set-Aside Remaining Generic Funds Remaining
Page 121 of 717
Joe Karkoski - 4 -
TABLE 1 – GWGP Round 3 Revised Funding Recommendations
Applicant Proposal Title DAC
Status
Funding
approved
2/9/23
Match
waiver
Revised
funding
amount
City of Dinuba Wellfield Groundwater
Quality Improvement and
Sustainability Project
SDAC $9,541,601 Waive $10,611,819
City of Turlock Downtown Turlock PCE
Project
DAC $14,640,045 Waive $17,269,997
City of El Monte* Former Crown City Plating
Site
DAC $1,901,250 Do not
waive
$1,901,250
(No change)
San Gabriel
Basin Water
Quality Authority
Whitmore Street
Groundwater Remediation
Facility Expansion
Implementation
DAC $1,850,735 Waive $3,701,470
City of Modesto Municipal Groundwater
Supply Contamination
Prevention and Cleanup
DAC $8,445,035 Waive $9,434,145
City of San Luis
Obispo
PCE Plume
Characterization
DAC $5,877,765 Waive $6,607,850
Alameda County
Water District
Brackish Groundwater
Reclamation Project
Non-
DAC
$2,205,094 Do not
waive
$2,205,094
(No change)
United Water
Conservation
District
Phase 1 Pumping of
Coastal Brackish
Groundwater Wells to
Control Seawater
Intrusion, Oxnard Basin
Non-
DAC
$8,449,062 Do not
waive
$8,449,062
(No change)
City of Pismo
Beach
Central Coast Blue Non-
DAC
$0 Do not
waive
$8,000,000
Totals: $52,910,587 $68,180,687
*The City of El Monte’s project, while serving a DAC, would not be eligible for a match waiver under
present circumstances. Water Code, section 79771(c), prohibits funding to be used to pay any share of
the costs of remediation recovered or recoverable from responsible parties . Under current circumstances,
54% of the project funds appear to be recoverable from a viable potentially responsible party, the property
owner.
2. GWGP staff should notify Round 3 applicants that will be affected by the approval of
a complete waiver of match requirements.
3. GWGP staff should notify the City of Pismo Beach about DFA’s funding decision,
superseding the funding determination letter dated March 17, 2023.
Page 122 of 717
Joe Karkoski -5 -
APPROVAL
I, Joe Karkoski, Deputy Director of the State Water Board’s Division of Financial
Assistance, approve staff’s recommendations described above.
Approved: _________________________
Joe Karkoski, Deputy Director
Division of Financial Assistance
Attachments (4)
1.Attachment A - Round 3 Funding Recommendation Narrative
2.Attachment B - Pismo Beach - Funding Determination Letter
3.Attachment C - Pismo Beach Central Coast Blue Funding Determination
4.Attachment D - Support for Central Coast Blue and Funding Determination
cc: Christopher Stevens
Division of Financial Assistance
Kim Dinh
Division of Financial Assistance
Debbie Cheung
Division of Financial Assistance
Kari Holzgang
Division of Financial Assistance
Anabel Ruiz
Division of Financial Assistance
Joseph Escobar
Division of Financial Assistance
David Maurer
Division of Financial Assistance
Catarina Hinojos
Division of Financial Assistance
Joe Karkoski Digitally signed by Joe Karkoski
Date: 2023.08.29 15:29:00
-07'00'
Page 123 of 717
Page 124 of 717
Groundwater Contamination
Characterization Project
Final Initial Study – Mitigated Negative Declaration
prepared by
City of San Luis Obispo
Utilities Department
879 Morro Street
San Luis Obispo, California 93401
Contact: Shawna Scott, Special Projects Manager
prepared with the assistance of
Rincon Consultants, Inc.
1530 Monterey Street, Suite D
San Luis Obispo, California 93401
February 2025
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Table of Contents
Final Initial Study – Mitigated Negative Declaration i
Table of Contents
Initial Study .............................................................................................................................................1
1. Project Title .........................................................................................................................1
2. Lead Agency/Project Sponsor Name and Address ..............................................................1
3. Contact Person and Phone Number ...................................................................................1
4. Project Location ..................................................................................................................1
5. General Plan and Zoning Designations ...............................................................................6
6. Description of Project .........................................................................................................6
7. Surrounding Land Uses and Setting ................................................................................. 10
8. Other Public Agencies Whose Approval is Required ....................................................... 10
9. Have California Native American Tribes Traditionally and Culturally Affiliated with
the Project Area Requested Consultation Pursuant to Public Resources Code
Section 21080.3.1? ........................................................................................................... 10
10. Public Review of the Draft Initial Study – Mitigated Negative Declaration ..................... 11
Environmental Factors Potentially Affected ........................................................................................ 14
Determination ..................................................................................................................................... 14
Environmental Checklist ...................................................................................................................... 16
1 Aesthetics ......................................................................................................................... 16
2 Agriculture and Forestry Resources ................................................................................. 20
3 Air Quality ........................................................................................................................ 22
4 Biological Resources ......................................................................................................... 28
5 Cultural Resources ........................................................................................................... 40
6 Energy .............................................................................................................................. 46
7 Geology and Soils ............................................................................................................. 48
8 Greenhouse Gas Emissions .............................................................................................. 54
9 Hazards and Hazardous Materials ................................................................................... 58
10 Hydrology and Water Quality .......................................................................................... 63
11 Land Use and Planning ..................................................................................................... 68
12 Mineral Resources ........................................................................................................... 7 0
13 Noise ................................................................................................................................ 72
14 Population and Housing ................................................................................................... 76
15 Public Services .................................................................................................................. 78
16 Recreation ........................................................................................................................ 80
17 Transportation ................................................................................................................. 82
18 Tribal Cultural Resources ................................................................................................. 86
19 Utilities and Service Systems ........................................................................................... 90
20 Wildfire ............................................................................................................................ 94
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City of San Luis Obispo
Groundwater Contamination Characterization Project
ii
21 Mandatory Findings of Significance ................................................................................. 96
References ......................................................................................................................................... 102
Bibliography ............................................................................................................................... 102
List of Preparers ......................................................................................................................... 105
Tables
Table 1 Construction Air Quality Thresholds of Significance ........................................................ 23
Table 2 Estimated Criteria Pollutant Emissions During Construction ........................................... 24
Table 3 Plant Species Potential to Occur at The Treatment Well Site .......................................... 29
Table 4 Animal Species Potential to Occur at The Treatment Well Site ....................................... 30
Table 5 Project Consistency with the Climate Action Plan ........................................................... 56
Table 6 Typical Noise Levels for Construction Equipment ........................................................... 73
Figures
Figure 1 Project Overview .................................................................................................................2
Figure 2 Treatment Well Site ............................................................................................................3
Figure 3 Site Photographs – General Project Location .....................................................................4
Figure 4 Site Photographs - Treatment Well Location ......................................................................5
Figure 5 Vegetation Communities and Land Cover Types ............................................................. 31
Appendices
Appendix A Air Quality and Greenhouse Gas Modeling
Appendix B Botanical Memorandum
Appendix C Noise and Vibration Calculations
Appendix D Draft IS-MND Comment Letters
Appendix E Mitigation Monitoring and Reporting Program
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Initial Study
Final Initial Study – Mitigated Negative Declaration 1
Initial Study
1. Project Title
Groundwater Contamination Characterization Project
2. Lead Agency/Project Sponsor Name and Address
City of San Luis Obispo
Public Utilities Department
879 Morro Street
San Luis Obispo, California 93401
3. Contact Person and Phone Number
Shawna Scott, Special Projects Manager
City of San Luis Obispo
Public Utilities Department
879 Morro Street
San Luis Obispo, California 93401-3218
4. Project Location
The project is located within the City of San Luis Obispo in San Luis Obispo County, California. The
project site is in the southern portion of the City along U.S. Highway 101 (U.S. 101) between Prado
Road and Los Osos Valley Road within Assessor’s Parcel Numbers 053-051-045, 053-052-045, 053-
131-013, 053-141-012, 053-152-006, 053-152-008, 053-153-014, and 053-153-008.
The approximately 30.4-acre project site encompasses a 22-acre site for the proposed groundwater
extraction and treatment wells and up to 12 potential monitoring locations with a 100-foot
surrounding buffer accounting for the remaining 8.4 acres. Figure 1 and Figure 2 provide a map
illustration of the project components, in a regional and local context. The treatment well site is
identified as a polygon boundary containing two treatment well locations TW-3 and TW-4,1 and the
monitoring well locations are identified as points MW-1 through MW-12. Representative site
photographs are provided in Figure 3 and Figure 4.
1 There are only two treatment wells proposed; however, during earlier planning stages the City considered other well locations in
addition to TW-3 and TW-4.
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City of San Luis Obispo
Groundwater Contamination Characterization Project
2
Figure 1 Project Overview
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Initial Study
Final Initial Study – Mitigated Negative Declaration 3
Figure 2 Treatment Well Site
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City of San Luis Obispo
Groundwater Contamination Characterization Project
4
Figure 3 Site Photographs – General Project Location
Photograph 1. View of the treatment well site, east of U.S. 101, facing west. Photograph taken on
April 26, 2024.
Photograph 2. View of the treatment well site, east of U.S. 101, facing northeast. Photograph taken on
April 26, 2024.
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Initial Study
Final Initial Study – Mitigated Negative Declaration 5
Figure 4 Site Photographs - Treatment Well Location
Photograph 3. View of the water distribution connection area, west of U.S. 101, facing northeast.
Photograph taken on April 26, 2024.
Photograph 4. View of the treatment well site, east of U.S. 101, facing northeast. Photograph taken on
June 5, 2024.
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City of San Luis Obispo
Groundwater Contamination Characterization Project
6
5. General Plan and Zoning Designations
The southern portion of the treatment well site is zoned Conservation/Open Space (C/OS-20) and
has a land use designation of Open Space. The northern portion is zoned Public Facility (PF) and
Public Facility-Special Considerations (PF-S) with a land use designa tion of Public. Monitoring wells
would be dispersed on City property or within City easements or right-of-way within the following
zones: Conservation/Open Space (C/OS-20), Medium Density Residential (R-2), Low-Density
Residential Specific Plan Overlay (R-1-SP), Public Facility (PF), Service Commercial (C-S), Service
Commercial Mixed Use Overlay (C-S-MU), Service Commercial Planned Development Overlay (C-S-
PD), Retail Commercial (C-R), Retail Commercial Planned development Overlay (C-R-PD), and Tourist
Commercial (C-T). The monitoring wells are on land designated with the following land uses: Service
and Manufacturing, General Retail, Tourist Commercial, Public, Low Density Residential, Medium
Density Residential, and Open Space.
6. Description of Project
The purpose of the project is to clean-up and prevent PCE (tetrachloroethylene) contamination in
drinking water supply wells in the San Luis Valley Subarea of the San Luis Obispo Valley
Groundwater Basin and to expand local water supply resiliency and reduce reliance on local surface
water supplies. In support of these goals, the City of San Luis Obispo proposes to install a network of
monitoring wells and two treatment wells with associated utility infrastructure and a treatment
system to monitor water levels and quality in the Subarea of the Basin, further characterize the PCE
plume, and monitor the effectiveness of removing PCE impacted groundwater from the Subarea of
the Basin. Funding for the implementation phase of the project includes California State Water
Resources Control Board (SWRCB) Proposition 1 Groundwater Grant Program Agreement No.
D2312550.
The project includes 12 possible monitoring well locations and one 22-acre site for the two
proposed extraction treatment wells and the proposed water distribution line. The 12 monitoring
well locations, water conveyance pipelines, and the 22-acre treatment well site collectively
represent the project site. Details for the proposed treatment and monitoring wells are provided
below.
Monitoring Wells
The monitoring wells would be drilled using a hollow-stem auger or rotary sonic drilling method
depending on the location and depth of the proposed location. The installation of the monitoring
wells is anticipated to require an area measuring approximately 40 feet by 10 feet to account for the
drill rig footprint. For the purposes of this assessment, a 100-foot buffer is added to the 40 feet by
10 feet to account for the work zone to accommodate the support truck and decontamination truck,
as well as the work area for the crew.
Construction of the monitoring wells would include:
Each well would be hand augured to a depth of approximately 4 to 8 feet below ground surface
as an additional precautionary method to avoid subsurface utilities or infrastructure.
Each well would consist of one 2-inch or 4-inch diameter, Schedule 40 Polyvinyl Chloride (PVC)
casing.
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Initial Study
Final Initial Study – Mitigated Negative Declaration 7
The annulus between the well casing and the formation would be backfilled with filter pack
(sand) and Portland cement.
A flush-mounted traffic rated steel well box would be installed over each well.
The newly completed monitoring wells would be developed using a combination of bailing,
surging, and pumping.
The wells would likely be 60 to 160 feet deep, with a possibility of a maximum depth of 200 feet.
The boreholes would be 10 inches in diameter, which would produce approximately 50 cubic
feet of cuttings per 100 feet of borehole.
Wastes derived from well installation and well development activities would include soil
cuttings, decontamination water, and development water. Soil cuttings and water would be
containerized in 55-gallon drums, temporarily stored on-site or at an appropriate location, and
profiled for disposal. These investigation-derived wastes would be transported off-site and
disposed of at an appropriate disposal facility in accordance with applicable regulations, if
needed.
As necessary, concrete or asphalt concrete coring would be conducted to penetrate the
concrete surface at each boring location. The concrete coring process would advance a 12-inch
diameter cutter through the concrete. The core would be considered complete when the core
can be removed, and native soil or base fill can be found beneath the concrete slab.
Treatment Wells
Treatment Well #3 (TW-3)
The U.S. 101 well proposed to be equipped for treatment (TW-3) was drilled, constructed, and
tested in February 2003, but has since been capped. The well has a 12-inch casing and is 145 feet
deep, with a 40-foot-deep sanitary seal, set back approximately 300 feet from San Luis Obispo
Creek. The proposed site layout for TW-3 includes new extraction well infrastructure (an
approximately 650-square foot building to house the treatment well, electrical panels, and
disinfection system) as well as the centralized treatment system (treatment pad with granulated
activated carbon (GAC) vessels and bag filters, as well as two backwash storage tanks). The
proposed TW-3 site layout would also include security fencing, utility infrastructure, entailing a new
6-inch sewer line connecting the backwash storage tank to the City’s sanitary sewer system, a new
12-inch water line connecting the treatment infrastructure to the City’s water distribution system,
and a new 8-inch water line connecting TW-3 to the Bob Jones Trail treatment well (TW-4). A gravel
access road would be constructed between TW-3 and an existing gravel road approximately 100
feet west of the TW-3 site to provide access to the TW-3 site. The utility infrastructure would be
installed in the same locations as the gravel access road and underneath the existing disturbed
access road as shown in Figure 3 and Figure 4. The affected area consists of approximately 0.27
acre, including placement of gravel, paving, and structural elements. Construction of this utility
infrastructure and the gravel access road would require the removal of three cypress trees and four
oak trees. Tree removal would occur consistent with the requirements of Chapter 12.24 of the City’s
Municipal Code, including compensatory tree planting and protection of surrounding trees to
remain.
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City of San Luis Obispo
Groundwater Contamination Characterization Project
8
Treatment Well #4 (TW-4)
TW-4 would involve drilling, construction, and testing of a new groundwater production well (Bob
Jones Trail Well). The affected area consists of approximately 0.31 acre, including placement of
gravel, paving, and structural elements. The sequence of work would include:
Mobilization to the well site and installation of sound barriers, if identified as a requirement by
the City.
Drilling and installing a 50-foot deep conductor casing, annular materials, and cement seal.
Drilling a pilot borehole to a depth of 205 below ground surface.
Conducting a geophysical logging and deviation survey of the completed pilot borehole, and
submitting formation samples selected by the City to a testing laboratory for grain size
distribution analysis.
Reaming the pilot borehole to the diameter and depth per final well design.
Construction of the well, including mechanical, chemical, and pumping well development.
Conducting well testing, including production tests, groundwater sampling and flowmeter
survey, and video camera survey and plumbness/alignment survey.
Disinfection of well casing and installation of well casing and tubing end caps.
Demobilization, clean-up, and restoration of the well site. Restoration would include restoring
the well location to pre-existing conditions in accordance with City Standard Specifications and
Engineering Standards, and replacing plants and groundcover temporarily affected by the
construction activities.
The TW-4 site layout would include perimeter security fencing, paving, and a 250-square-foot, one-
story secure building to house the well and electrical panels. The building would be configured with
a removable roof (or hatch) for future well maintenance. In addition, TW-4 includes a new gravel
access road, connecting the TW-4 location to the existing Bob Jones Trail.
Construction Schedule/Staging/Equipment
Construction of the monitoring wells is anticipated to occur from April 2025 to October 2025.
Drilling of TW-4 is anticipated to occur from March 2025 to August 2025. Well equipping2 would
begin in June 2025 and would be completed in July 2026. Construction of the TW-3 site would occur
between August 2025 and February 2026. Construction of the TW-4 site would occur between
August 2025 and February 2026. Construction activities would generally occur within the City’s
permitted hours between 7:00am and 7:00pm Monday through Saturdays. However, some
construction activities may necessitate work outside of these hours in the event utility infrastructure
is shut off during the day but must be made operational the next day (e.g., water lines). Well drilling
is expected to last 40 days, and major Project construction activities associated with the
development of the TW sites visible from U.S. 101 would last approximately 120 working days.
All work would be conducted on City property or within City easement or right-of-way. Access to
TW-4 would be provided by approximately 200 feet of new gravel access road in two approximately
100-foot segments, connecting the TW-4 location to the existing Bob Jones Trail. No work would
occur within Caltrans right-of-way, aside from the installation of a water distribution pipe within an
existing casing located under U.S. 101. The following equipment is anticipated for all work: bucket
auger drill rig for conductor, tremie pipe, cement truck and concrete pump (conductor casing), hand
2 Well equipping refers to the process of outfitting a drilled well with all necessary components to make the well operational.
Page 136 of 717
Initial Study
Final Initial Study – Mitigated Negative Declaration 9
auger, hollow-stem auger or rotary sonic drill, support/water and decontamination truck,
decontamination trailer, forklift or backhoe, Baker tank(s) for development water, roll off
bins/drums for soil.
A plastic tarp and containment berm would be placed beneath the drilling rig during mobilization to
protect the site against oil or hydraulic fluid spills or leaks and would remain beneath the rig until
demobilization. A plastic tarp of the same thickness and containment berm would also be placed
beneath other stationary equipment such as air compressors and fuel tanks. Containment berm
protection for any fuel tanks would be equal to or greater than the maximum fuel capacity of the
tank(s).
Soil Disposal
Approximately 45 cubic yards of drill cuttings and approximately 7,400 gallons of drilling mud would
be generated at TW-4. Up to approximately 4 cubic yards of drill cuttings would be generated at
each monitoring well site. The total volume of drill cuttings is expected to be up to approximately
90-100 cubic yards. The construction contractor would be required to contain and store all
investigation-derived waste, including drill cuttings and drilling mud. Cuttings would not be allowed
to be stored on the ground due to the potential for the presence of PCE.
The construction contractor would be required to submit samples of drilling spoils for analytical
testing required for waste profiling. Based on the results of the analytical testing the drilling spoils
will be containerized, transported, and disposed of at the appropriate waste disposal facility. The
construction contractor would complete appropriately required waste disposal manifests and bills
of lading and submit such documents to the City of San Luis Obispo for signature and approval prior
to transporting waste from each monitoring well site. The construction contractor would furnish to
the City one original waste disposal manifest signed and certified by the disposal facility confirming
the volume and receipt of waste materials.
Operation and Monitoring
The project would extract groundwater from the San Luis Valley subarea of the San Luis Obispo
Valley Basin. The San Luis Valley subarea has an estimated surplus of 700 acre-feet per year (AFY).
The proposed combined pumping distribution for the two extraction and treatment wells will not
exceed 600 AFY. The two extraction and treatment wells will extract PCE-impacted groundwater
from the target aquifers and transport it to a ce ntralized facility for treatment using GAC. The GAC
media is designed to adsorb contaminants, including PCE during treatment. Once the media is
spent, as observed by the presence of PCE at the middle point of the treatment system during
routine water sampling, a GAC media exchange will be scheduled. The City will work with a qualified
vendor to supply new media and dispose of the spent media. Disposal options for GAC include
profiling and disposal at an Environmental Protection Agency (EPA)-approved landfill, incineration,
or regeneration. Due to the relatively low PCE concentrations, it is anticipated that approximately
one bed (20,000 pounds) of GAC will need to be disposed of annually.
The City is required to prepare and implement an Operations and Maintenance Plan for the
proposed groundwater extraction and water distribution to ensure compliance with DDW
regulations and the Sustainable Groundwater Management Act (SGMA) and adopted Groundwater
Sustainability Plan (GSP). A component of this plan includes groundwater level and pumping
monitoring at the extraction/treatment wells to ensure compliance with the GSP. The GSP identifies
sustainability indicators (which are used to define undesirable results), including but not limited to,
depletion of interconnected surface water (San Luis Obispo Creek). The GSP includes minimum
Page 137 of 717
City of San Luis Obispo
Groundwater Contamination Characterization Project
10
thresholds for this sustainability indicator, including an identified groundwater level elevation (96
feet) at a monitoring well located proximate to San Luis Creek. As defined in the GSP, minimum
thresholds refer to numeric values and are established at representative monitoring sites. Minimum
thresholds are indicators of where an unreasonable condition might occur.
In addition to the monitoring well identified in the GSP, the monitoring wells proposed as part of the
project will also provide groundwater level data, and will be equipped with telemetry to monitoring
pumping, and allow for automatic adjustments in pumping rates. The GSP is required to be updated
every five years, and the additional data collected from these new monitoring wells will inform
these updates and further support GSP-compliance.
The proposed monitoring wells will also provide the ability to monitor groundwater quality, further
enhance the characterization of the PCE plume and monitor the effectiveness of the groundwater
treatment facilities installed for the project. The monitoring wells will be sampled according to the
following schedule: initially, once after installation to collect baseline data; quarterly for the first five
years; and subsequently at the frequency specified in the project’s Monitoring and Reporting Plan
(WSC, 2024).
7. Surrounding Land Uses and Setting
The treatment well site is surrounded by U.S. 101 and commercial development to the north and
west, the City Water Resource Recovery Facility (WRRF) to the north, and San Luis Obispo Creek to
the east and south. U.S. 101 is partially included within the treatment well site, but no work is
proposed as part of the project that would directly affect U.S. 101 or occur in the U.S. 101 right-of-
way. The monitoring well sites are primarily located in developed residential and commercial
portions of the City.
8. Other Public Agencies Whose Approval is Required
The City of San Luis Obispo is the lead agency with approval over the proposed project. The City will
obtain permits from the County of San Luis Obispo for the new extraction well and each monitoring
well. The project will require approval from the California Department of Drinking Water.
9. Have California Native American Tribes Traditionally
and Culturally Affiliated with the Project Area
Requested Consultation Pursuant to Public Resources
Code Section 21080.3.1?
Native American Tribes were notified on July 25, 2024 about the project consistent with City and
State regulations including, but not limited to, Assembly Bill 52. During the request for consultation
window, two responses were received. The Santa Ynez Band of Chumash Indians contacted the City
on August 5, 2024 requesting a consultation meeting to discuss the project. The City consulted with
the Tribe on September 17, 2024 and shared information regarding the project, the results of the
cultural resources survey, and proposed mitigation measures. The Tribe informed the City that they
are in agreement with the mitigation measures laid out in the public review Draft IS-MND for a
workers environmental awareness program training, archaeological monitoring, and protocol in the
event of unanticipated discoveries. The Salinan Tribe of Monterey responded on August 30, 2024
requesting notification in the event of a cultural resource discovery during construction. It is
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Initial Study
Final Initial Study – Mitigated Negative Declaration 11
standard policy to notify local Native American tribes in the event of a cultural resource discovery
during construction; in addition, specific language has been added to CUL-3 requiring notification of
Native American tribal representatives. Pursuant to PRC §21080.3.1 (b) the request for consultation
window closed on August 26, 2024. No other tribal agencies responded to the consultation request.
In addition, the IS-MND was provided to Native American Tribes during the public review period.
The City received additional correspondence from the Santa Ynez Band of Chumash Indians,
consisting of a request for minor modifications to the language of mitigation measure CUL-1
(Workers Environmental Awareness Program Training). The Final IS-MND incorporates the
requested amendment into CUL-1. The City also received a request for maps and photos of the
project area and the archaeological report including record-search information from the Northern
Chumash Tribal Council; this information was provided by City staff and no further comments were
received.
10. Public Review of the Draft Initial Study – Mitigated
Negative Declaration
The Draft Initial Study – Mitigated Negative Declaration (IS-MND) was circulated for a 30-day public
review period that began on December 12, 2024 and ended on January 10, 2025. The City of San
Luis Obispo received three comment letters on the Draft IS-MND from State resource agencies, one
from the SWRCB, Division of Drinking Water, one from the California Department of Fish and
Wildlife (CDFW) Central Region 4, and one from the California Department of Transportation
(Caltrans). All comment letters are included in Appendix D to the Final IS-MND. Additions and
clarifications presented in this Final IS-MND are indicated in underlined format.
The SWRCB’s letter describes the agency’s role as a responsible agency and provides comments
recommending additional operational detail be added to the project description, discussion of
granulated activated carbon (GAC) replacement be added to the hazardous materials evaluation,
and discussion of the project’s relationship to the San Luis Valley Groundwater Basin be discussed.
The Final IS-MND includes additional details regarding the project’s compliance and consistency
with the Groundwater Sustainability Plan (GSP), operation of the wells and treatment systems, and
management of the granulated activated carbon (GAC) media. The sustainable management of the
San Luis Valley Basin as described in the GSP includes provisions for the use of groundwater by the
City. As noted in the supplemental project description details regarding operation and maintenance
of the extraction and treatment wells, the City would comply with the San Luis Obispo Valley Basin
Groundwater Sustainability Plan (GSP) by: implementing an Operations and Maintenance Plan and
Monitoring and Reporting Plan; pumping not more than 600 acre-feet per year (afy), which is less
than the San Luis Valley subarea’s identified groundwater surplus (700 afy); groundwater quality,
groundwater level, and pumping monitoring at the groundwater extraction and monitoring wells;
using telemetry data to automatically adjust pumping rates based on groundwater levels; and
complying with minimum thresholds identified in the GSP to avoid conditions such as depletion of
interconnected surface waters (San Luis Obispo Creek).
CDFW’s letter describes the agency’s role as a responsible agency and provides comments and
recommendations related to identifying and mitigating the project’s potential impacts on fish and
wildlife resources. While the IS-MND circulated for public review included and discussed potential
impacts to species identified by CDFW, the Final IS-MND incorporates revisions and additions that
respond to CDFW’s comments and incorporate CDFW’s recommendations, including additional
mitigation requirements to further reduce the project’s potential impacts on the State Candidate
western burrowing owl (Athene cunicularia hypugaea) and Crotch’s bumble bee (Bombus crotchii).
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City of San Luis Obispo
Groundwater Contamination Characterization Project
12
The Final IS-MND also addresses CDFW’s comments regarding State species of special concern and
federally threatened South-Central California Coast steelhead (S-CCC steelhead) (Oncorhynchus
mykiss irideus pop. 9). The Final IS-MND includes new and revised language supporting the
determination that the project would have less than significant impacts to water and riparian
resources, including interconnected surface waters and groundwater dependent ecosystems. As
noted above, operation of the project is required to comply with the GSP and identified thresholds
established for undesirable results, such as depletion of waters in San Luis Obispo Creek; therefore,
the project would not create a condition that results in significant impacts to steelhead. In addition
to these comments, CDFW recommends coordination with CDFW staff prior to groundbreaking
activities onsite or submission of a Lake or Streambed Alteration (LSA) Notification to determine if
the activities proposed within the streams are subject to CDFW’s jurisdiction. The project does not
propose activity within streams, and the City’s required compliance with the GSP will ensure that
the proposed groundwater extractions would not “substantially divert or obstruct the natural flow
of any river, stream, or lake; therefore, the project does not include the conditions that would
require a LSA.
The letter provided by Caltrans includes a list of the items that would be required as part of the
encroachment permit that the City will request from Caltrans for installation of the water
distribution line within the existing casing under U.S. 101. No specific comments regarding the Initial
Study were provided, and as noted, the City will submit an encroachment permit application to
Caltrans and will comply with the requirements of that application submittal and permit.
In addition, the City received additional correspondence from the Santa Ynez Band of Chumash
Indians during the public review period for the IS/MND. The Tribe requested minor modifications to
the language of mitigation measure CUL-1 (Workers Environmental Awareness Program Training), to
include a requirement for a Chumash Tribal Representative to be present during the training. The
Final IS-MND incorporates this language into CUL-1.
CEQA Guidelines Section 15073.5 describes the requirements for recirculation of an IS-MND prior to
adoption:
a) A lead agency is required to recirculate a negative declaration when the document must be
substantially revised after public notice of its availability has previously been given pursuant
to Section 15072, but prior to its adoption. Notice of recirculation shall comply with Sections
15072 and 15073.
b) A “substantial revision” of the negative declaration shall mean:
1) A new, avoidable significant effect is identified and mitigation measures or project
revisions must be added in order to reduce the effect to insignificance, or
2) The lead agency determines that the proposed mitigation measures or project revisions
will not reduce potential effects to less than significance and new measures or revisions
must be required.
c) Recirculation is not required under the following circumstances:
1) Mitigation measures are replaced with equal or more effective measures pursuant to
Section 15074.1.
2) New project revisions are added in response to written or verbal comments on the
project's effects identified in the proposed negative declaration which are not new
avoidable significant effects.
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Initial Study
Final Initial Study – Mitigated Negative Declaration 13
3) Measures or conditions of project approval are added after circulation of the negative
declaration which are not required by CEQA, which do not create new significant
environmental effects and are not necessary to mitigate an avoidable significant effect.
4) New information is added to the negative declaration which merely clarifies, amplifies,
or makes insignificant modifications to the negative declaration.
Additional information and mitigation details have been added to the Final IS-MND in response to
the comments and recommendations provided by CDFW and SWRCB. However, the added
mitigation measures do not create new significant environmental effects and are not necessary to
mitigate an avoidable significant effect. The new information that has been added to the Final IS-
MND clarifies, amplifies, or makes insignificant modifications to the mitigated negative declaration.
Therefore, the City of San Luis Obispo concludes that the additions and revisions described herein
do not require recirculation of the Draft IS-MND pursuant to CEQA Guidelines Section 15073.5.
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City of San Luis Obispo
Groundwater Contamination Characterization Project
14
Environmental Factors Potentially Affected
This project would potentially affect the environmental factors checked below, involving at least
one impact that is “Potentially Significant” or “Less than Significant with Mitigation Incorporated” as
indicated by the checklist on the following pages.
■ Aesthetics □ Agriculture and
Forestry Resources
■ Air Quality
■ Biological Resources ■ Cultural Resources □ Energy
■ Geology and Soils □ Greenhouse Gas
Emissions
□ Hazards and Hazardous
Materials
□ Hydrology and Water
Quality
□ Land Use and Planning □ Mineral Resources
■ Noise □ Population and
Housing
□ Public Services
□ Recreation □ Transportation ■ Tribal Cultural Resources
□ Utilities and Service
Systems
□ Wildfire ■ Mandatory Findings
of Significance
Determination
Based on this initial evaluation:
□ I find that the proposed project COULD NOT have a significant effect on the environment,
and a NEGATIVE DECLARATION will be prepared.
■ I find that although the proposed project could have a significant effect on the environment,
there will not be a significant effect in this case because revisions to the project have been
made by or agreed to by the project proponent. A MITIGATED NEGATIVE DECLARATION will
be prepared.
□ I find that the proposed project MAY have a significant effect on the environment, and an
ENVIRONMENTAL IMPACT REPORT is required.
□ I find that the proposed project MAY have a “potentially significant impact” or “less than
significant with mitigation incorporated” impact on the environment, but at least one effect
(1) has been adequately analyzed in an earlier document pursuant to applicable legal
standards, and (2) has been addressed by mitigation measures based on the earlier analysis
as described on attached sheets. An ENVIRONMENTAL IMPACT REPORT is required, but it
must analyze only the effects that remain to be addressed.
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Determination
Final Initial Study – Mitigated Negative Declaration 15
□ I find that although the proposed project could have a significant effect on the environment,
because all potential significant effects (a) have been analyzed adequately in an earlier EIR
or NEGATIVE DECLARATION pursuant to applicable standards, and (b) have been avoided or
mitigated pursuant to that earlier EIR or NEGATIVE DECLARATION, including revisions or
mitigation measures that are imposed upon the proposed project, nothing further is
required.
Signature Date
Printed Name Title
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City of San Luis Obispo
Groundwater Contamination Characterization Project
16
Environmental Checklist
1 Aesthetics
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Except as provided in Public Resources Code
Section 21099, would the project:
a. Have a substantial adverse effect on a
scenic vista? □ □ ■ □
b. Substantially damage scenic resources,
including but not limited to, trees, rock
outcroppings, and historic buildings
within a state scenic highway? □ □ ■ □
c. In non-urbanized areas, substantially
degrade the existing visual character or
quality of public views of the site and its
surroundings? (Public views are those
that are experienced from a publicly
accessible vantage point). If the project is
in an urbanized area, would the project
conflict with applicable zoning and other
regulations governing scenic quality? □ □ ■ □
d. Create a new source of substantial light or
glare that would adversely affect daytime
or nighttime views in the area? □ ■ □ □
Environmental Setting
The project site is located in the San Luis Valley, within the southern portion of the City of San Luis
Obispo, in San Luis Obispo County, California. The to pography of the treatment well site is relatively
flat, with an approximate elevation ranging from 111 to 126 feet above mean sea level, sloping
southward, with an average slope of 2 percent. Immediately surrounding land uses include
transportation/roadways, including U.S. 101 and commercial development to the north and west,
the City WRRF to the north, and San Luis Obispo Creek to the east and south (refer to Figure 2). San
Luis Obispo Creek is immediately east and parallel to the eastern boundary of the treatment well
site and Laguna Lake is approximately 0.6 mile to the northwest. The treatment well site is located
on vegetative grasses and open space (refer to Figure 1). The monitoring well sites are located
throughout the City, on City property or within City easements or right-of-way. The majority of the
monitoring well locations are paved, except for MW-4, which is located on aggregate and topsoil.
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Environmental Checklist
Aesthetics
Final Initial Study – Mitigated Negative Declaration 17
The nearest officially designated state scenic highway, State Route 1,3 is approximately three miles
north of the treatment well site. There is no line of sight between this portion of State Route 1 and
the treatment well site. West of the treatment well site, State Route 1 and U.S. 101 converge and
share a designation of an Eligible Scenic Highway (Caltrans 2019). The City identifies the portion of
U.S 101 adjacent to the treatment well site as having high scenic value. However, no scenic vistas
are identified through the treatment well site. The nearest scenic vista is located 0.6 mile north,
with north facing views from Madonna Road (City of San Luis Obispo 2014a).
Impact Analysis
a. Would the project have a substantial adverse effect on a scenic vista?
b. Would the project substantially damage scenic resources, including but not limited to, trees,
rock outcroppings, and historic buildings within a state scenic highway?
The project site is not located in an area with an identified scenic vista. The project site is not visible
from or located within the viewsheds experienced at Madonna Road (i.e., views of Laguna Lake
Park, Irish Hills Natural Preserve, and Cerro San Luis) or any other designated scenic vista. Although
the treatment well site is located along a high scenic value portion of State Route 1/U.S. 101, which
is an Eligible Scenic Highway, project construction activities visible from U.S. 101 would be
temporary, lasting approximately 120 working days. These temporary construction activities would
not restrict views of scenic vistas through the treatment well site. Following construction
completion, the treatment wells and associated structural infrastructure would not preclude views
of surrounding scenic vistas as the height of proposed infrastructure would not pose substantial
impediments to existing views. The monitoring wells do not include any development or structures;
work would be conducted in the subsurface. Post completion, a flush-mounted traffic rated steel
well box would be installed over each monitoring well. Therefore, the monitoring wells would not
provide any visual impediments to surrounding scenic vistas.
There are no rock outcroppings, or historic buildings at the treatment well site locations, and no
rock outcropping, or historic buildings would be modified or otherwise impacted as a result of the
project. The project would remove seven trees to install the access road and utility infrastructure.
The treatment well site and surroundings are lined with trees along San Luis Obispo Creek and the
minimal tree removal required for the project would not have a substantial adverse effect on public
views from U.S. 101 or the surrounding area.
The project would not include infrastructure with the potential to substantially affect views of scenic
vistas and no rock outcropping, or historic buildings would be modified or otherwise impacted as a
result of the project. The project would not have a substantial adverse effect on a scenic vista or
damage scenic resources within a state scenic highway. Therefore, these impacts would be less than
significant.
LESS-THAN-SIGNIFICANT IMPACT
3 State Route 1 is officially designated as a scenic highway starting at the intersection of Santa Rosa Street and Highland Drive. At its
convergence with U.S. 101 adjacent to the treatment well site it is designated as an eligible state scenic highway.
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City of San Luis Obispo
Groundwater Contamination Characterization Project
18
c. Would the project, in an urbanized area, conflict with applicable zoning and other regulations
governing scenic quality?
The project site is adjacent to commercial, residential, public facilities uses, and U.S. 101. Given the
population density of the City of San Luis Obispo, and the developed nature of the project site and
its surroundings, the project is evaluated as an urban area consistent with CEQA Guidelines Section
15387.4 Therefore, this discussion examines if the project would conflict with City zoning and other
regulations governing scenic quality.
The southern portion of the treatment well site is zoned Conservation/Open Space (C/OS-20), and
the northern portion is zoned Public Facility (PF) and Public Facility-Special Considerations (PF-S).
The monitoring wells would not introduce above-ground infrastructure, and therefore, would not
result in conflicts with regulations related to scenic quality. The treatment wells would introduce
new above-ground infrastructure to the treatment well site such as perimeter security fencing,
buildings to house each well and electrical panels, two GAC vessels, and two storage tanks within
the Conservation/Open Space (C/OS-20), Public Facility (PF) and Public Facility-Special
Considerations (PF-S) zones. These zones permit public service infrastructure. The proposed project
would not interfere with established setbacks in these zones and would not exceed height
requirements or otherwise interfere with regulations governing scenic quality in these zones. The
project would not conflict with applicable zoning and other regulations governing scenic quality or
substantially degrade existing visual character or quality. Therefore, this impact would be less than
significant.
LESS-THAN-SIGNIFICANT IMPACT
d. Would the project create a new source of substantial light or glare that would adversely affect
daytime or nighttime views in the area?
Pursuant to Municipal Code Section 9.12.050, construction work is limited to daytime hours
between 7:00 a.m. and 7:00 p.m. unless discretionary approval for nighttime work is granted by the
City’s Community Development Department. Daytime work would not require the use of temporary
flood lights or other light/glare generating sources during the day. Nighttime work, if necessary,
would be carried out in accordance with lighting provisions set forth by the City’s Community
Development Department. However, nighttime construction work would have the potential to
constitute a temporary source of new light that may affect nighttime views. This impact would be
potentially significant.
Once construction activities are completed, potential sources of light may include shielded security
lighting. Any exterior lighting would be required to be consistent with the City’s Lighting and Night
Sky Preservation standards, which require that outdoor lighting is fully shielded and directed
downward and away from adjacent properties and public rights-of-way. Therefore, operation of the
project would not create a new source of substantial light or glare which would adversely affect day
or nighttime views in the area, and this impact would be less than significant.
4 The population of San Luis Obispo is approximately 48,684 (California Department of Finance 2024). CEQA Guidelines Section 15387
provides that an urbanized area means a city with a population of 50,000 or an area having a population density of at least 1,000 persons
per square mile. San Luis Obispo is approximately 13.2 square miles, providing a population density of approximately 3,688 persons per
square mile. Therefore, San Luis Obispo meets the criteria of an urbanized area pursuant to CEQA Guidelines 15387.
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Environmental Checklist
Aesthetics
Final Initial Study – Mitigated Negative Declaration 19
Mitigation Measures
AES-1 Nighttime Work Requirements
In the event nighttime work is necessary during the project construction phase, any portable lighting
shall be shielded and/or directed away from adjacent properties. Night lighting for construction
activities shall be the minimum necessary to ensure safety and security for nighttime activities and
operations. Lighting at the project site shall consist of light-emitting diode lights in all areas where
nighttime construction activities will occur and be either motion-activated or use timers to ensure
safety and security and reduce the impact of additional light pollution at night. The City shall verify
compliance with the construction night lighting requirements via an inspection during nighttime
construction activities.
Significance After Mitigation
Implementation of AES-1 would reduce potential project impacts related to nighttime lighting to a
less than significant level by requiring shielding of lighting.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
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City of San Luis Obispo
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20
2 Agriculture and Forestry Resources
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Convert Prime Farmland, Unique Farmland,
or Farmland of Statewide Importance
(Farmland), as shown on maps prepared
pursuant to the Farmland Mapping and
Monitoring Program of the California
Resources Agency, to non-agricultural use? □ □ □ ■
b. Conflict with existing zoning for agricultural
use or a Williamson Act contract? □ □ □ ■
c. Conflict with existing zoning for, or cause
rezoning of, forest land (as defined in
Public Resources Code Section 12220(g));
timberland (as defined by Public Resources
Code Section 4526); or timberland zoned
Timberland Production (as defined by
Government Code Section 51104(g))? □ □ □ ■
d. Result in the loss of forest land or
conversion of forest land to non-forest
use? □ □ □ ■
e. Involve other changes in the existing
environment which, due to their location
or nature, could result in conversion of
Farmland to non-agricultural use or
conversion of forest land to non-forest
use? □ □ ■ □
Environmental Setting
The California Department of Conservation’s (DOC) Farmland Mapping and Monitoring Program
classifies the treatment well site and each of the 12 monitoring well locations as Urban and Built-Up
Land, which is defined as land that is occupied by structures with a building density of at least one
unit to 1.5 acres (DOC 2022). The treatment well site is zoned Conservation/Open Space (C/OS-20),
Public Facility (PF) and Public Facility-Special Considerations (PF-S). The treatment and monitoring
well sites are not located within active agricultural uses, land zoned for agriculture, or classified
forest land (City of San Luis Obispo 2014a).
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Environmental Checklist
Agriculture and Forestry Resources
Final Initial Study – Mitigated Negative Declaration 21
Impact Analysis
a. Would the project convert Prime Farmland, Unique Farmland, or Farmland of Statewide
Importance (Farmland), as shown on maps prepared pursuant to the Farmland Mapping and
Monitoring Program of the California Resources Agency, to non-agricultural use?
b. Would the project conflict with existing zoning for agricultural use or a Williamson Act
contract?
Construction equipment and well sites would be staged within individual work zones on City
property or within City easement or right-of-way. No portions of the project are located on land
designated as Prime Farmland, Unique Farmland, or Farmland of Statewide Importance as mapped
by the DOC (DOC 2022). As such, there is no potential for the project to convert such lands to non-
agricultural uses. No portions of the project are currently zoned for agriculture or held under
Williamson Act or any other land conservation contract. The project would not convert Farmland or
conflict with existing zoning for agricultural use or a Williamson Act contract. Therefore, no impact
would occur.
NO IMPACT
c. Would the project conflict with existing zoning for, or cause rezoning of, forest land (as defined
in Public Resources Code Section 12220(g)); timberland (as defined by Public Resources Code
Section 4526); or timberland zoned Timberland Production (as defined by Government Code
Section 51104(g))?
d. Would the project result in the loss of forest land or conversion of forest land to non-forest use?
No portions of the project are located on land that is in current timberland production, including
any lands designated as forest land or timberland. Therefore, the project would not conflict with
existing zoning for forest land, timberland, or timberland zoned Timberland Production, or result in
the loss of forest land or conversion of forest land to non-forest use. No impact would occur.
NO IMPACT
e. Would the project involve other changes in the existing environment which, due to their
location or nature, could result in conversion of Farmland to non-agricultural use or conversion
of forest land to non-forest use?
No portions of the project are located on forest land or timberland. The portion of the project
adjacent to the City Farm and San Luis Ranch agricultural area would be located within an existing
easement, and within an existing access road along Highway 101; furthermore, infrastructure would
be below ground, consisting of an underground water distribution pipe. No lands under cultivation
would be affected by the project. Therefore, the project would not result in the conversion of
Farmland to non-agricultural use or conversion of forest land to non-forest use. Impacts would be
less than significant.
LESS-THAN-SIGNIFICANT IMPACT
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3 Air Quality
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Conflict with or obstruct implementation
of the applicable air quality plan? □ □ □ ■
b. Result in a cumulatively considerable net
increase of any criteria pollutant for
which the project region is non-
attainment under an applicable federal
or state ambient air quality standard? □ □ ■ □
c. Expose sensitive receptors to substantial
pollutant concentrations? □ □ ■ □
d. Result in other emissions (such as those
leading to odors) adversely affecting a
substantial number of people? □ ■ □ □
Environmental Setting
The project site is located in the South Central Coast Air Basin (SCCAB) which covers San Luis Obispo,
Santa Barbara, and Ventura counties (California Air Resources Board [CARB] 2014). The San Luis
Obispo Air Pollution Control District (SLOAPCD) monitors and regulates the local air quality in San
Luis Obispo County and enforces the Clean Air Plan. SLOAPCD is required to monitor air pollutant
levels to ensure that National Ambient Air Quality Standards (NAAQS) and California Ambient Air
Quality Standards (CAAQS) are met and, if they are not met, to develop strategies to meet the
standards.
Depending on whether the standards are met or exceeded, the SCCAB is classified as being in
“attainment” or “nonattainment” for air quality. The SCCAB is in nonattainment for the federal
standards for ozone (eastern San Luis Obispo County only) and the state standards for ozone, and
particulate matter less than 10 microns in diameter (PM10). The SCCAB is designated in attainment
for all other federal and state standards (SLOAPCD 2019).
SLOAPCD is required to prepare a plan for air quality improvement for pollutants for which its
jurisdiction is in nonattainment. Because the SCCAB is currently designated nonattainment for
federal and State standards for ozone and State standards for PM10, SLOAPCD is required to
implement strategies that would reduce pollutant levels to recognized acceptable standards.
SLOAPCD adopted the Clean Air Plan in 2001 which evaluates long-term emissions and establishes
programs to reach acceptable air quality levels (SLOAPCD 2001). SLOAPCD has also adopted the
Particulate Matter Report to identify strategies to reduce public exposure to particulate matter, and
the Ozone Emergency Episode Plan which provides the basis for taking action when ambient ozone
concentrations reach a level that poses a threat to public health in the County (SLOAPCD 2005;
SLOAPCD 2020).
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Environmental Checklist
Air Quality
Final Initial Study – Mitigated Negative Declaration 23
SLOAPCD provides numerical thresholds to analyze the significance of a project’s construction and
operational impacts on regional air quality. These thresholds, listed in Table 1, are designed such
that a project with estimated emissions that do not exceed the thresholds would not have an
individually or cumulative significant impact on the air quality of the SCCAB.
Table 1 Construction Air Quality Thresholds of Significance
Threshold
Pollutant
Daily
(pounds per day)
Quarterly Tier 1
(tons per quarter)
Quarterly Tier 2
(tons per quarter)
ROG + NOx (combined) 137 2.5 6.3
Diesel Particulate Matter (DPM) 7 0.13 0.32
Fugitive Particulate Matter (PM10), Dust – 2.5 –
ROG = Reactive Organic Gases; NOx = Nitrous Oxides
Source: SLOAPCD 2023
Sensitive receptors typically include residences, schools, healthcare facilities, and other live-in
housing facilities such as prisons or dormitories. The closest sensitive receptors to the monitoring
wells include single-family residences located approximately 15 feet east of MW-10, a single-family
residence located approximately 45 feet north of MW-06, a single-family residence located
approximately 50 feet east of MW-01, and mobile homes located approximately 65 feet north of
MW-03. The closest sensitive receptors to the treatment well site are single-family residences
located approximately 245 feet east of the treatment well site. The portion of the Bob Jones Trail
within the treatment well site is a recreational use which is not considered a sensitive receptor.
Impact Analysis
a. Would the project conflict with or obstruct implementation of the applicable air quality plan?
The applicable air quality plan is the SLOAPCD Clean Air Plan. Based on SLOAPCD’s CEQA Air Quality
Handbook (2023), if a project is consistent with the land use assumptions and transportation control
measures within the Clean Air Plan, the project would be consistent with the Clean Air Plan
(SLOAPCD 2023). The transportation control measures within the Clean Air Plan are primarily
related to providing alternative transportation options, enhancing bike infrastructure, and
circulation management (SLOAPCD 2001). Because the proposed project would not result in
population growth or result in changes to existing City land use designations or long-term
transportation patterns, the transportation control measures in the Clean Air Plan are not directly
applicable to the proposed project, and the proposed project would not conflict with the population
projections and land use assumptions of the Clean Air Plan. Therefore, the proposed project would
not conflict with or obstruct implementation of SLOAPCD’s Clean Air Plan, and no impact would
occur.
NO IMPACT
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Groundwater Contamination Characterization Project
24
b. Would the project result in a cumulatively considerable net increase of any criteria pollutant for
which the project region is non-attainment under an applicable federal or state ambient air
quality standard?
The California Emissions Estimator Model (CalEEMod), version 2022.1.1.22 was used to estimate the
project’s air pollution emissions. CalEEMod uses project-specific information, including a project’s
land uses, construction equipment parameters, and location, to model a project’s construction
emissions. Operation of the proposed project would generate a nominal amount of air pollutants
from minimal electricity consumption and vehicle trips to the well sites for maintenance activities
and would not result in substantial air pollutant emissions or generate a cumulatively considerable
net increase of any criteria pollutant for which the SCCAB is in nonattainment. Therefore, for the
purposes of this analysis, only construction emissions were modeled and compared to SLOAPCD
construction emission thresholds. CalEEMod modeling outputs are included in Appendix A.
Table 2 shows the proposed project’s estimated criteria air pollutant emissions and compares the
emissions to SLOPACD thresholds. Construction of the proposed project would not exceed SLOAPCD
construction thresholds and would not result in a cumulatively considerable net increase of any
criteria pollutant for which the SCCAB is in nonattainment. Therefore, this impact would be less than
significant.
Table 2 Estimated Criteria Pollutant Emissions During Construction
Estimated Emissions
ROG NOx CO SO2 PM10 PM2.5
Construction Emissions (pounds per day) 6.3 48.0 55.7 0.2 1.9 1.6
Construction Emissions (tons per quarter) 0.1 0.6 0.7 <0.01 0.03 0.02
SLOAPCD Thresholds (Daily) 137 pounds per day
(combined ROG
and NOx)
N/A N/A N/A 7 pounds
per day
SLOAPCD Thresholds (Quarterly) 2.5 tons
(combined ROG
and NOx)
N/A N/A 2.5 tons 0.13 tons
Thresholds Exceeded? No N/A N/A No No
ROG = reactive organic gases; NOX = nitrogen oxides; CO = carbon monoxide; SO2 = sulfur dioxide; PM10 = particulate matter 10
microns or less in diameter; PM2.5 = particulate matter 2.5 microns or less in diameter
Source: SLOAPCD 2023; Appendix A
LESS-THAN-SIGNIFICANT IMPACT
c. Would the project expose sensitive receptors to substantial pollutant concentrations?
Fugitive Dust
Most of the proposed monitoring wells would be located in paved areas with minimal potential to
generate substantial fugitive dust. However, MW-11 would be constructed approximately 815 feet
from single-family residences, and TW-3, TW-4, and MW-09 would be constructed approximately
450 west of single-family residences. As described in Threshold 3(b), the project would not result in
particulate matter emissions that would exceed SLOAPCD’s regional thresholds. Construction
personnel would be required to adhere to California Code of Regulations Title 13 Section 2485,
which prohibits idling of diesel-powered vehicles for over five minutes to minimize diesel particulate
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Environmental Checklist
Air Quality
Final Initial Study – Mitigated Negative Declaration 25
matter emissions. In addition to these requirements, SLOAPCD guidelines require projects that
would disturb greater than four acres within 1,000 feet of a sensitive receptor to implement
standard mitigation measures to minimize fugitive dust emissions (SLOAPCD 2023). For project
construction activities at all sites, the City’s Special Provisions and specifications would require the
contractor implement applicable SLOAPCD fugitive dust measures as best management practices to
minimize localized fugitive dust emissions during construction. These measures include, but are not
limited to, watering to prevent airborne dust, stabilization of soils, limiting vehicle speeds on the
project site, and use of devices to prevent sand or dirt from falling out of trucks during transport
(SLOAPCD 2023). With the inclusion and implementation of SLOAPCD’s standard mitigation for
fugitive dust emissions reduction, the proposed project’s potential to expose sensitive receptors to
substantial fugitive dust emissions would be less than significant.
Naturally Occurring Asbestos
Naturally occurring asbestos (NOA) has been identified by CARB as a toxic air contaminant.
Serpentinite and ultramafic rocks are common throughout San Luis Obispo and may contain
naturally occurring asbestos (SLOAPCD 2018). Under CARB’s Air Toxic Control Measures related to
construction and grading, a geologic evaluation is required to determine of NOA is present prior to
any grading activities at the project site. If NOA is identified at the site during ground-disturbing
activities, requirements outlined in CARB’s Air Toxic Control Measures would be enforced, in
addition to requirements stipulated in the National Emission Standard for Hazardous Air Pollutants
(40 Code of Federal Regulations Section 61, Subpart M -Asbestos). These requirements include
notifying SLOAPCD at least 10 days prior to commencing construction, preparing an asbestos survey
conducted by a Certified Asbestos Consultant, and implementation of removal and disposal protocol
and requirements for identified NOA. A SLOAPCD Permit to Operate for Excavation of Contaminated
Soils is included in the City’s Standard Specifications and Engineering Standards (August 2020). This
Permit states that required Naturally Occurring Asbestos and NESHAP requirements have been met,
and monitoring, recordkeeping, and District notification procedures are in place. With adherence to
the SLOAPCD permit and State requirements for NOA abatement, the proposed project would have
a less than significant impact on sensitive receptors due to the presence of NOA.
LESS-THAN-SIGNIFICANT IMPACT
d. Would the project result in other emissions (such as those leading to odors) adversely affecting
a substantial number of people?
The project would not involve operation of any land uses identified by SLOAPCD that may generate
substantial odors, such as asphalt batch plants, chemical manufacturing, sanitary landfill, or a
wastewater treatment plant (SLOAPCD 2023). Construction would generate temporary odors
associated with diesel exhaust emitted by construction equipment. These odors would be localized
to the project site and restricted to the duration of equipment use, which would be temporary and
infrequent. The distances between both treatment well sites and receptors and most monitoring
well sites and receptors are generally large enough such that construction would not result in
nuisance due to odors. In addition, construction personnel would be required to adhere to idling
restrictions for on- and off-road vehicles and equipment which would minimize diesel odors.
However, due to the proximity of MW-01, MW-06, and MW-10 to single-family residences, there is
potential that construction of these monitoring wells could result in short-term nuisance due to
odors at nearby residences. This impact would be potentially significant.
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26
Mitigation Measure
AQ-1 Odor Reduction
Where construction activities occur within 50 feet of a sensitive receptor, the construction
contractor shall implement the following additional idling restrictions, which shall be shown on
grading and construction plans:
Idling Restrictions Near Sensitive Receptors for Both On- and Off-Road Equipment
Staging and queuing areas shall be located at the greatest distance feasible from sensitive
receptor locations;
Diesel idling while equipment is not in use is not permitted;
Use of alternative-fueled equipment is recommended whenever possible; and
Signs that specify the no-idling requirements shall be posted and enforced at the
construction site.
The City Utilities Department shall verify these measures are located on construction plans prior to
the start of construction. Once during construction, City Inspector shall visit the project site to verify
these idling restrictions have been implemented.
Significance After Mitigation
Implementation of Mitigation Measure AQ-1 would ensure construction within 50 feet of sensitive
receptors would not result in substantial odors affecting the adjacent single-family residence
through implementation of idling restrictions. Implementation of Mitigation Measure AQ-1 would
reduce the proposed project’s impact related to odors to a less than significant level.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
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4 Biological Resources
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Have a substantial adverse effect, either
directly or through habitat modifications,
on any species identified as a candidate,
sensitive, or special status species in local
or regional plans, policies, or regulations, or
by the California Department of Fish and
Wildlife or U.S. Fish and Wildlife Service? □ ■ □ □
b. Have a substantial adverse effect on any
riparian habitat or other sensitive natural
community identified in local or regional
plans, policies, or regulations, or by the
California Department of Fish and Wildlife
or U.S. Fish and Wildlife Service? □ □ ■ □
c. Have a substantial adverse effect on state
or federally protected wetlands (including,
but not limited to, marsh, vernal pool,
coastal, etc.) through direct removal, filling,
hydrological interruption, or other means? □ □ ■ □
d. Interfere substantially with the movement
of any native resident or migratory fish or
wildlife species or with established native
resident or migratory wildlife corridors, or
impede the use of native wildlife nursery
sites? □ □ ■ □
e. Conflict with any local policies or
ordinances protecting biological resources,
such as a tree preservation policy or
ordinance? □ □ ■ □
f. Conflict with the provisions of an adopted
Habitat Conservation Plan, Natural
Community Conservation Plan, or other
approved local, regional, or state habitat
conservation plan? □ □ □ ■
Rincon prepared a Botanical Survey Memorandum (Botanical Memorandum, Appendix B) in June
2024 to summarize methodology and results of protocol-level botanical surveys and literature
review to determine presence or absence of federally and/or State-listed or other special-status
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plant species within the treatment well site. Surveys were carried out in accordance with the
California Native Plant Survey’s (CNPS) Botanical Survey Guidelines and the California Department of
Fish and Wildlife’s (CDFW) Protocols for Surveying and Evaluating Impacts to Special Status Native
Plant Populations and Natural Communities. The botanical surveys were conducted in April and June
of 2024, and were timed to capture the flowering periods of all special-status plant species
determined to have a low, moderate, or high potential to occur on-site based on the literature
review and regionally specific knowledge. The monitoring well locations were not evaluated for the
potential to support sensitive plant or animal species, or other potentially significant biological
resources, as each of the monitoring well locations outside of the treatment well site would be
developed on locations that are paved and feature existing infrastructure (as confirmed based on
site visits conducted by City staff), and thus do not present the potential for encountering sensitive
biological resources.
In addition, in July 2024, Rincon conducted a review of the California Natural Diversity Database
(CNDDB) using a 5-Mile radius buffer, a review of the CNPS inventory, and completed an evaluation
of the species-specific potential to occur at the treatment well site, based on a site visit on July 15,
2024 and the CNDDB/CNPS results (also included in Appendix B). The setting and impact analysis
provided are summarized based on the results of the Botanical Memorandum and CNDDB
documentation.
Environmental Setting
Plant Species
The CNDDB and CNPS identified 121 special-status plant and lichen species with documented
occurrences within a five-mile radius of the treatment well site. Of these plant and lichen species, 11
have a low potential to occur, five have a moderate potential to occur, and four have a high
potential to occur at the treatment well site.
Table 3 provides an overview of the CNDDB and CNPS results for species with moderate and high
potential to occur.
Table 3 Plant Species Potential to Occur at The Treatment Well Site
Species
Potential
to Occur
Potentially Suitable Habitat
Present at Treatment Well Site
club-haired mariposa-lily (Calochortus clavatus var. clavatus) High Yes
Cambria morning-glory (Calystegia subacaulis ssp. episcopalis) High Yes
San Luis Obispo owl’s-clover (Castilleja densiflora var. obispoensis) High Yes
Jones’ layia (Layia jonesii) High Yes
Congdon’s tarplant (Centromadia parryi ssp. congdonii) Moderate Yes
Chorro Creek bog thistle (Cirsium fontinale var. obispoense) Moderate Yes
large-flowered leptosiphon (Leptosiphon grandifloras) Moderate Yes
adobe sanicle (Sanicula maritima) Moderate Yes
saline clover (Trifolium hydrophilum) Moderate Yes
Source: Appendix B
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Animal Species
The CNDDB review identified five invertebrate species, two fish species, five amphibian species, two
reptile species, 20 bird species, and eight mammal species with documented occurrences within a
five-mile radius of the treatment well site. Of these animal species, 16 have a low potential to occur,
six have a moderate potential to occur, and two have a high potential to occur at the treatment well
site.
Table 4 provides an overview of the CNDDB results for species with moderate and high potential to
occur at the treatment well site.
Table 4 Animal Species Potential to Occur at The Treatment Well Site
Species Potential to Occur
Potentially Suitable Habitat Present at
Treatment Well Site
California red-legged frog (Rana draytonii) High Yes
loggerhead shrike (Lanius ludovicianus) High Yes
Crotch’s bumble bee (Bombus crotchii) Moderate Yes
burrowing owl (Athene cunicularia) Moderate Yes
ferruginous hawk (Buteo regalis) Moderate Yes
Merlin (Falco columbarius) Moderate Yes
pallid bat (Antrozous pallidus) Moderate Yes
American badger (Taxidea taxus) Moderate Yes
Source: Appendix B
Land Cover Types/Vegetation Communities
Rincon conducted a review of vegetation communities present at the site, which are shown in
Figure 5. A description of these vegetation communities is provided below.
DEVELOPED
Developed land cover consists of areas that have been previously developed or modified to the
extent that they no longer contain native soil and habitat conditions and no longer support most
vegetation. This land cover type may also contain areas that are sparsely vegetated, primarily with
non-native species. Within the treatment well site, these areas include buildings, paved areas and
roadways, and gravel or hardpacked dirt roadways. This land cover type occurs throughout the
treatment well site and is associated with commercial development west of U.S. 101, the City
corporation yard and the WRRF, and existing paved and unpaved roadways and trails.
Approximately 8.3 acres of this land cover type is present.
AGRICULTURE
Agriculture consists of areas associated with existing agricultural operations. Within the treatment
well site (the area proposed for a water distribution pipe and connection to the City’s existing water
distribution system), these areas consist of hoop houses and row crops associated with existing
agricultural operations. This land cover type occurs in the northwest portion of the treatment well
site, west of U.S. 101. Approximately 0.2 acre of this land cover type is present.
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Figure 5 Vegetation Communities and Land Cover Types
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ORNAMENTAL
Ornamental land cover includes areas with planted vegetation, such as windbreaks, privacy screens,
lawns, or other landscaped areas. Ornamental areas are located throughout the treatment well site
and are often found adjacent to developed areas, particularly along roads, trails, and the San Luis
Obispo treatment plant. Planted species within ornamental areas on-site include pepper tree
(Schinus molle), Monterey pine (Pinus radiata), coast live oak (Quercus agrifolia), olive (Olea
europea), Santa Cruz island ironwood (Lyonothamnus floribundus ssp. aspleniifolius), wattle (Acacia
sp.), glossy privet (Ligustrum lucidum), and toyon (Heteromeles arbutifolia). Approximately 4.7 acres
of this land cover type is present.
COYOTE BRUSH SCRUB
Coyote brush scrub (Baccharis pilularis Shrubland Alliance) is a native coastal scrub vegetation
community that occurs on coastal bluffs, terraces, stabilized dunes, stream sides, and other similar
areas and features variable soils with sandy or relatively heavy clay. Coyote brush (Baccharis
pilularis) is dominant to co-dominant in the shrub canopy, occupying at least 50 percent absolute
cover in the shrub canopy. This vegetation community is typically less than three meters tall, the
shrub canopy is variable, and the herbaceous layer is variable. This vegetation community is ranked
G5S5 and is not classified as a CDFW sensitive natural community (CDFW 2024a). Coyote brush
scrub is present in several small patches in the southeastern portion of the treatment well site.
These patches are associated with larger, undisturbed areas of coyote brush scrub immediately
south of the treatment well site. Within the treatment well site, coyote brush is the dominant
species in the shrub canopy, with non-native herbaceous species including slender oat, cheeseweed
mallow (Malva parviflora), and milk thistle (Silybum marianum) present in the herbaceous layer.
Less than 0.1 acre of this vegetation community is present.
FENNEL PATCHES
Fennel patches (Foeniculum vulgare, Herbaceous Semi-Natural Alliance) are a native vegetation
community found across all topography between 0 and 1,000 meters. Fennel (Foeniculum vulgare)
contributes at least 50 percent relative cover in the herbaceous layer, and the herbaceous layer is
open to continuous. This vegetation community is not considered a CDFW sensitive natural
community (CDFW 2024a). Fennel patches are present along the existing unpaved roadway that
runs parallel to U.S. 101 in the eastern portion of the treatment well site. Within the treatment well
site, fennel is the dominant species in the herbaceous layer, with non-native wild radish (Raphanus
sativus) and bristly ox-tongue (Helminthotheca echioides) also present at lower cover.
Approximately 0.1 acre of this vegetation community is present.
UPLAND MUSTARD FIELDS
Upland mustard fields (Brassica nigra, Herbaceous Semi-Natural Alliance) are an open to continuous
semi-naturalized non-native vegetation community that occurs within fallow fields, rangelands,
grasslands, roadsides, and disturbed coastal scrub habitats. The soils are variable and contain clay to
sandy loams. This vegetation community is dominated by non-native ruderal forbs (e.g., black
mustard, short podded mustard [Hirschfeldia incana], and tocalote [Centaurea melitensis]). This
vegetation community is not classified as a CDFW sensitive natural community (CDFW 2024a).
Upland mustard fields are present throughout the treatment well site and are typically associated
with developed areas subject to frequent human disturbance, including paved and unpaved
roadways and trails. Within the treatment well site, dominant species within this vegetation
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community include non-native black mustard, short-podded mustard, tocalote, and prickly lettuce.
Other non-native species present include slender oat, bristly ox-tongue, Bermuda grass (Cynodon
dactylon), poison hemlock (Conium maculatum), and castor bean (Ricinus communis).
Approximately 3.9 acres of this vegetation community is present.
WILD OATS GRASSLAND
Wild oats grassland (Avena spp., Semi-Natural Alliance) is an open-to-dense naturalized vegetation
community that is dominated or co-dominated by non-native, often invasive, annual grasses (e.g.,
wild oats [Avena spp.] and foxtail barley [Hordeum murinum]). This vegetation community is often
interspersed with native and non-native forbs. Emergent trees and shrubs may be present but at
low cover. This vegetation community is not classified as a CDFW sensitive natural community
(CDFW 2024a). Wild oats grassland is present throughout the eastern portion of the treatment well
site and typically occurs in open areas adjacent to existing paved and unpaved roadways. Within the
treatment well site, this vegetation community is subject to frequent human disturbance in the
form of routine mowing and vegetation maintenance. Dominant species in the herbaceous layer
include slender oat and foxtail barley, with non-native prickly lettuce, field bindweed, and bristly ox-
tongue also present. Several small patches of native grasses, including purple needlegrass (Stipa
pulchra) and creeping wildrye (Elymus triticoides), are also present within this vegetation
community on-site. Additionally, several emergent coast live oak trees are present within this
vegetation community on-site. Approximately 5.6 acres of this vegetation community is present.
Impact Analysis
a. Would the project have a substantial adverse effect, either directly or through habitat
modifications, on any species identified as a candidate, sensitive, or special status species in
local or regional plans, policies, or regulations, or by the California Department of Fish and
Wildlife or U.S. Fish and Wildlife Service?
Plant Species
Each of the monitoring well locations outside of the treatment well site would be developed on
locations that are paved and feature existing infrastructure, and thus do not present the potential
for encountering sensitive plant species. The CNDDB and CNPS review identified five plant species
with a moderate potential to occur and four plant species with a high potential to occur at the
treatment well site. Based on the results of the Botanical Memorandum (Appendix B), no federal-
listed, state-listed, or other special-status plant species were observed at the treatment well site
during the botanical surveys. Therefore, no special-status plant species are present at the treatment
well site, and the project would have no impact on special-status plant species.
Animal Species
Each of the monitoring well locations outside of the treatment well site would be developed on
locations that are paved and feature existing infrastructure, and thus would not affect animal
species or their habitats. As summarized in Table 4, the CNDDB review identified six animal species
with a moderate potential to occur and two animal species with a high potential to occur at the
treatment well site. While no federal-listed, state-listed, or other special-status animal species were
observed at the treatment well site during field visits conducted in April, June, and July 2024, the
treatment well site does contain suitable habitat for these species. In addition to these species, the
project site contains suitable nesting habitat for nesting bird species. Due to the presence of
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suitable habitat at the treatment well site, project construction could result in the direct disturbance
of these special-status species (i.e., injury or mortality) if individuals are present in the work area
during construction. Furthermore, destruction or abandonment of native bird nests would violate
the California Fish and Game Code and Migratory Bird Treaty Act. These regulations make it
unlawful to take, possess, or destroy birds of prey and migratory birds, and their nests and eggs.
Therefore, potential direct impacts to special-status animal species are potentially significant.
Construction would also have the potential to result in indirect impacts to special-status species
through the potential introduction of sediment or pollutants to San Luis Obispo Creek. As detailed in
Section 7, Geology and Soils, the City’s construction contractor would be required to obtain
coverage under the General Permit for Storm Water Discharges Associated with Construction and
Land Disturbance Activities, Order No. 2022-0057-DWQ, NPDES No. CAS000002 (Construction
Stormwater General Permit), and would also be required to comply with the City’s standard BMPs
for erosion and sedimentation control (as required by the City’s adopted Standard Specifications
and Engineering Standards) which would ensure that best management practices (BMP) are
implemented which would minimize erosion and stormwater pollution. With adherence to the
Construction Stormwater General Permit and mandatory City Standards, the project would not
introduce substantial erosion or other pollutants into San Luis Obispo Creek and would not result in
substantial indirect impacts on the riparian habitat on the treatment well site or within San Luis
Obispo Creek.
Operation of the project would not involve extraction of a substantial volume of groundwater that
could have the potential to significantly impact groundwater levels or result in an undesirable
condition such as depletion of interconnected surface water. In July 2024, the Treatment Well Siting
Analysis for the Bob Jones Trail Well and Highway 101 Well was reviewed by the Department of
Drinking Water (DDW). The City’s consultant, WSC, conducted the EPA’s Assessment of
Groundwater Under the Influence of Surface Water (GWUDISW) for both proposed
extraction/treatment well sites, and neither well scored above 40, which indicates that the
groundwater near these wells is unlikely to be under the direct influence of surface water, and
pumping is unlikely to impact surface water in the creek.
The City is required to prepare and implement an Operations and Maintenance Plan for the
proposed groundwater extraction and water distribution to ensure compliance with DDW
regulations and the Sustainable Groundwater Management Act (SGMA) and adopted Groundwater
Sustainability Plan (GSP). A component of this plan includes groundwater level and pumping
monitoring at the extraction/treatment wells to ensure compliance with the GSP. The GSP identifies
sustainability indicators (which are used to define undesirable results), including but not limited to,
depletion of interconnected surface water (San Luis Obispo Creek) and minimum thresholds for this
sustainability indicator. In addition to the monitoring well identified in the GSP, the monitoring wells
proposed as part of the project will also provide groundwater level data, and will be equipped with
telemetry to monitoring pumping, and allow for automatic adjustments in pumping rates. The
project includes this ongoing monitoring and the ability to automatically adjust pumping rates to
ensure compliance with the GSP and avoid significant impacts to San Luis Obispo Creek and
steelhead (in addition to other species present within the creek).
Regarding indirect impacts to nesting birds, in general, avian species can typically avoid direct
impacts from construction activity. However, construction activity around any active nests could
result in nest abandonment because of noise, vibrations, or human activity. Accordingly, project
construction could indirectly impact nesting birds, and this impact would be potentially significant.
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Mitigation Measures
BIO-1 Worker Environmental Awareness Program
Prior to initiation of construction activities at the treatment well site, all personnel associated with
project construction shall attend a Worker Environmental Awareness Program (WEAP) training,
conducted by a qualified biologist, to aid workers in recognizing special-status species and nesting
birds that may occur within the project site. The specifics of this program shall include identification
of special-status species with potential to occur, a description of their regulatory status and habitat
requirements, general ecological characteristics of any other sensitive resources, and a review of
the limits of construction and measures required to avoid and/or reduce impacts to biological
resources within the project site. A fact sheet conveying this information shall also be prepared for
distribution to the construction contractor. All employees shall sign a form provided by the biologist
indicating they have attended the WEAP training and understand the information presented to
them. The construction foreman shall ensure crew members are aware of project boundaries and
adhere to the mitigation measures designed to avoid or minimize effects to listed species, nesting
birds, and other special-status species.
BIO-2 Pre-Construction Survey for Special-Status Wildlife Species
A qualified biologist shall conduct a pre-construction survey of the treatment well site and adjacent
habitat no more than two weeks prior to the start of construction at the treatment well site. The
biologist shall document the presence or absence of any special-status wildlife species with
potential to occur within the treatment well site plus a 50-foot buffer. The pre-construction survey
shall include surveys for burrowing owl that follow the “Burrowing Owl Survey Protocol and
Mitigation Guidelines” (California Burrowing Owl Consortium [CBOC] 1993) and CDFW’s “Staff
Report on Burrowing Owl Mitigation” (California Department of Fish and Game [CDFG] 2012) within
areas of suitable habitat during the survey season immediately prior to construction.
If special-status species are observed onsite during the pre-construction surveys, they shall be
allowed time to leave or be relocated prior to the initiation of construction activities. If special-
status species are present during construction activities, they shall be handled in accordance with
Mitigation Measure BIO-3 BIO-7.
BIO-3 Burrowing Owl Buffers
If burrows known to be currently or previously occupied by burrowing owl are found, either during
surveys or project activities, a 500-meter no-disturbance buffer shall be established around each
burrow.
BIO-4 Burrowing Owl Take Authorization
If burrowing owl individuals or burrows known to be currently or previously occupied by burrowing
owl are found, either during surveys or project activities, the City of San Luis Obispo shall consult
with CDFW to discuss how to implement the project and avoid take. If avoidance is not feasible,
acquisition of a State Incidental Take Permit pursuant to California Fish and Game Code Section
2081 subdivision (b), prior to any ground disturbing activities, shall be required in order to comply
with the California Endangered Species Act.
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BIO-5 Crotch’s Bumble Bee Habitat Assessment and Surveys
A qualified biologist shall conduct a habitat assessment to determine if the project area and the
immediate surrounding vicinity contain habitat suitable to support Crotch’s bumble bee. The
assessment shall document potential nesting sites, which include all small mammal burrows,
perennial bunch grasses, thatched annual grasses, brush piles, old bird nests, dead trees, and hollow
logs.
If potentially suitable habitat for Crotch’s bumble bee is identified in the habitat assessment, the
qualified biologist shall conduct focused surveys for Crotch’s bumble bee and their requisite habitat
features, following the methodology outlined in the Survey Considerations for California
Endangered Species Act Candidate Bumble Bee Species (CDFW 2023).
BIO-6 Crotch’s Bumble Bee Buffers and Take Authorization
If Crotch’s bumble bee is detected during the required habitat assessment and surveys, all small
mammal burrows and thatched/bunch grasses shall be avoided by a minimum of 50 feet to avoid
take of Crotch’s bumble bee. If ground-disturbing activities would occur during the overwintering
period (October through February), the City of San Luis Obispo shall consult with CDFW to discuss
how to implement project activities and avoid take. Any detection of Crotch’s bumble bee prior to
or during project implementation warrants consultation with CDFW to discuss how to avoid take.
If avoidance is not feasible, acquisition of a State Incidental Take Permit pursuant to California Fish
and Game Code Section 2081 subdivision (b), prior to any ground disturbing activities, would be
required in order to comply with the California Endangered Species Act.
BIO-37 Biological Monitoring and Special-Status Species Relocation
A qualified biologist shall be onsite at the treatment well site during all vegetation removal, initial
ground disturbing activities, and/or during any construction activities that may impact sensitive
biological resources. If the biologist discovers special-status animal species on the project site, the
biologist shall have the authority to temporarily halt or redirect work to avoid potential impacts. If
avoidance is not feasible, the biologist shall be responsible for relocating wildlife species out of the
treatment well site in accordance with the requirements of applicable regulatory agencies, such as
CDFW or the United States Fish and Wildlife Service. Special-status wildlife shall not be handled
without prior permission from the necessary regulatory agencies. Species-specific monitoring
requirements may be superseded or added to by resource agency permits and/or incidental take
authorizations. Following the relocation of wildlife, the biologist shall submit a report to the City
confirming the methodology and results of relocating the wildlife.
BIO-48 Nesting Bird Surveys
A preconstruction nesting bird survey shall be conducted by a qualified biologist no more than 14
days prior to initiation of project construction activities. The survey shall be conducted within the
treatment well site and include a 50-foot buffer for passerines and a 500-foot buffer for raptors. The
survey shall be conducted by a biologist familiar with the identification of avian species known to
occur in the region and shall focus on trees, vegetated areas, and other potential nesting within the
vicinity of the treatment well site. If active nests are identified in the survey, an appropriate
avoidance buffer (typically 50 feet for passerine species and 500 feet for raptors) shall be
determined and demarcated by the biologist with high visibility material located within or adjacent
to the treatment well site. All project personnel shall be notified as to the existence of the buffer
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zones and to avoid entering buffer zones during the nesting season. No project construction
activities shall occur within the buffer until the biologist has confirmed that breeding/nesting is
complete, and the young have fledged the nest. Encroachment into the buffer shall occur only at the
discretion of the qualified biologist.
Significance After Mitigation
Implementation of Mitigation Measures BIO-1 through BIO-4 8 would require worker environmental
awareness training, pre-construction surveys for special-status species and nesting birds, biological
monitoring and avoidance of special-status species and nesting birds, and, if necessary, relocation of
special-status species. With implementation of Mitigation Measures BIO-1 through BIO-48, direct
and indirect impacts to special-status species would be reduced to a less than significant level.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
b. Would the project have a substantial adverse effect on any riparian habitat or other sensitive
natural community identified in local or regional plans, policies, or regulations, or by the
California Department of Fish and Wildlife or U.S. Fish and Wildlife Service?
Each of the monitoring well locations outside of the treatment well site would be developed on
locations that are paved and feature existing infrastructure, and thus do not present the potential to
affect riparian habitat or sensitive natural communities. As described in the environmental setting
and shown in Figure 5, there are five vegetation communities at the treatment well site. None of
these vegetation communities are identified as sensitive natural communities. San Luis Obispo
Creek and its associated riparian habitat are located adjacent to the treatment well site; however,
the project would not directly impact this riparian habitat. As described in Section 10, Hydrology and
Water Quality, adherence to the Construction Stormwater General Permit and the City’s mandatory
Standard Specifications and Engineering Standards would ensure appropriate BMPs are
implemented to minimize erosion and stormwater pollution, ensuring construction at the treatment
well site would not indirectly affect the riparian habitat of San Luis Obispo Creek through the
introduction of stormwater pollutants.
In addition, as described above, operation of the project would not involve extraction of a
substantial volume of groundwater that could have the potential to significantly impact
groundwater levels or result in an undesirable condition such as depletion of interconnected surface
water. The City is required to prepare and implement an Operations and Maintenance Plan for the
proposed groundwater extraction and water distribution to ensure compliance with DDW
regulations and the Sustainable Groundwater Management Act (SGMA) and adopted Groundwater
Sustainability Plan (GSP). The project includes this ongoing monitoring and the ability to
automatically adjust pumping rates to ensure compliance with the GSP and avoid significant impacts
to San Luis Obispo Creek and associated waters and riparian habitat.
Therefore, the project result in less than significant direct and indirect impacts to riparian habitats or
other sensitive natural communities.LESS-THAN-SIGNIFICANT IMPACT
c. Would the project have a substantial adverse effect on state or federally protected wetlands
(including, but not limited to, marsh, vernal pool, coastal, etc.) through direct removal, filling,
hydrological interruption, or other means?
Each of the monitoring well locations outside of the treatment well site would be developed on
locations that are paved and feature existing infrastructure, and thus do not present the potential to
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affect wetlands. Based on a review of the National Wetlands Inventory, no wetlands are located on
the treatment well site or any of the monitoring well locations, but wetland habitat does exist
within San Luis Obispo Creek (United States Fish and Wildlife Service 2024). As described in
Threshold 4(b), construction would occur in accordance with the requirements of the Construction
Stormwater General Permit and the City’s mandatory Standard Specifications and Engineering
Standards, which would minimize the potential for erosion to fill or otherwise adversely affect San
Luis Obispo Creek. With regulatory adherence, the project would have a less than significant impact
related to wetland habitat.
LESS-THAN-SIGNIFICANT IMPACT
d. Would the project interfere substantially with the movement of any native resident or
migratory fish or wildlife species or with established native resident or migratory wildlife
corridors, or impede the use of native wildlife nursery sites?
Each of the monitoring well locations outside of the treatment well site would be developed on
locations that are paved and feature existing infrastructure, and thus do not present substantial
habitat connectivity. Based on a review of the CDFW Biogeographic Information and Observation
System, the treatment well site is not located in an area of substantial habitat connectivity (CDFW
2024b). The treatment well site is adjacent to commercial, residential, public facilities uses, and U.S.
101, and as such does not provide effective migration corridors for terrestrial species. San Luis
Obispo Creek is adjacent to the treatment well site; however, as described in Threshold 4(b),
regulatory compliance would minimize potential indirect impacts to San Luis Obispo Creek which,
subsequently, would minimize potential impacts to aquatic habitat utilizing San Luis Obispo Creek
for movement or nursery sites. Therefore, the project would have a less than significant impact
related to wildlife movement.
LESS-THAN-SIGNIFICANT IMPACT
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e. Would the project conflict with any local policies or ordinances protecting biological resources,
such as a tree preservation policy or ordinance?
The project would not interfere with the long-term natural function of the treatment well site’s
open space, consistent with the City’s policies to protect natural communities and avoid habitat
disturbance pursuant to the Conservation and Open Space Element of the General Plan (City of San
Luis Obispo 2014b). The monitoring well locations are all located on City property or within City
easement. The project would remove seven trees to install the access road and utility infrastructure.
Tree removal would occur consistent with the requirements of Chapter 12.24 of the City’s Municipal
Code, including compensatory tree planting (minimum 1:1 ratio). There is adequate area within the
City-owned parcel proposed for the treatment well site to accommodate the compensatory
plantings. All proximate trees proposed to remain would be avoided and preserved pursuant to the
City’s mandatory Standard Specifications and Engineering Standards for tree protection. The project
would not conflict with any local policies or ordinances protecting biological resources; therefore,
impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
f. Would the project conflict with the provisions of an adopted Habitat Conservation Plan, Natural
Community Conservation Plan, or other approved local, regional, or state habitat conservation
plan?
The project site is not located in any applicable adopted Habitat Conservation Plan, Natural
Community Conservation Plan, or other approved local, regional, or state habitat conservation plan
(City of San Luis Obispo 2006). Therefore, no impact would occur.
NO IMPACT
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5 Cultural Resources
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Cause a substantial adverse change in the
significance of a historical resource
pursuant to §15064.5? □ □ ■ □
b. Cause a substantial adverse change in the
significance of an archaeological resource
pursuant to §15064.5? □ ■ □ □
c. Disturb any human remains, including
those interred outside of formal
cemeteries? □ ■ □ □
Rincon prepared a Cultural Resources Technical Report (CRTR) dated May 2024 which includes a
California Historical Resources Information System (CHRIS) records search through the Central Coast
Information Center (CCIC); a Native American Heritage Commission (NAHC) Sacred Lands File (SLF)
search; background research including in-depth review, archival, academic, and ethnographic
information; a review of a feasibility study that summarizes historical data and background studies
to understand the current PCE plume; a cultural resources pedestrian survey of the project site; an
analysis of the sensitivity of the project site to contain cultural resources; as well as management
recommendations. The setting and impact analysis provided are summarized based on the results of
the CRTR.5
Environmental Setting
On April 29, 2024, CCIC staff at the Santa Barbara Museum of Natural History conducted a CHRIS
records search to identify previously recorded cultural resources within the project site (treatment
well site and 12 monitoring well locations) and a 0.5-mile radius surrounding it. The CHRIS records
search identified 177 previous cultural resource studies within the 0.5-mile records search area, 29
of which address portions of the project site. The records search identified 256 previously recorded
cultural resources within the 0.5-mile records search radius. Of these, three are mapped as within
the project site: two historic buildings and/or structures and one historic period Chinese American
Cemetery. Of the remaining 253 previously recorded cultural resources, 25 are prehistoric and/or
historic period archaeological sites, four are prehistoric isolated cultural materials, and 224 are built
environment resources.
5 The report contains sensitive and confidential information concerning archaeological sites and is therefore held confidential not for
public distribution. Archaeological site locations are exempt from the California Public Records Act, as specified in Government Code
6254.10, and from the Freedom of Information Act (Exemption 3), under the legal authority of both the National Historic Preservation Act
(PL 102-574, Section 304[a]) and the Archaeological Resources Protection Act (PL 96-95, Section 9[a]).
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Final Initial Study – Mitigated Negative Declaration 41
Impact Analysis
a. Would the project cause a substantial adverse change in the significance of a historical resource
pursuant to §15064.5?
The CHRIS records search identified two previously recorded cultural resources within the treatment
well site and one resource overlapping MW-02 and MW-03: two historic buildings and/or structures
and one historic period Chinese American Cemetery. One of the resources identified within the
treatment well site is documented as the San Luis Obispo WRRF and is mapped in CCIC records as
overlapping approximately 60 percent of the eastern portion of the treatment well site; however,
these areas are undeveloped and/or are developed with the Bob Jones Trail used for recreational
purposes and no buildings or structures associated with the facility were identified within the
project site. The other resource mapped within the treatment well site, Dalidio Ranch, is mapped in
CCIC records as overlapping approximately 5 percent of the northwestern portion of the treatment
well site; however, this portion of the treatment well site is undeveloped. Only minor utility
installations associated with the project would occur in this location and would not alter any existing
structures. Considering the absence of Dalidio Ranch structures and that the project would not
affect existing WRRF structures, the project would not affect historical resources associated with
Dalidio Ranch or the WRRF. According to the CRTR, the Chinese American Cemetery is mapped in
CCIC records as overlapping two monitoring well locations; however, the CRTR states review of
historical aerials and archival research suggests that it is possible that the resource is mapped
further south than what is captured in CCIC records, west and outside of the monitoring well
locations. Furthermore, there are no structures on at the monitoring well sites that suggest the
presence of a cemetery as the treatment well site is primarily undeveloped aside from the Bob
Jones Trail. Due to the lack of historic structures indicating the presence of a cemetery, the project
would not cause a substantial change in the significance of the cemetery. Therefore, the project
would not result in the substantial adverse change in the significance of a historical resource
pursuant to CEQA Guidelines Section 15064.5. Impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
b. Would the project cause a substantial adverse change in the significance of an archaeological
resource pursuant to §15064.5?
The NAHC SLF search returned a positive result; no informal outreach was conducted as part of the
CRTR.6 Refer to Section 18, Tribal Cultural Resources for a summary of formal tribal consultation
conducted for the project. The cultural resources pedestrian survey performed as part of the CRTR
focused on areas with exposed ground surfaces, which was limited to the treatment well site and
location of MW-09. The pedestrian field survey did not identify any cultural materials. Given the
developed nature of monitoring well locations MW-01 through MW-08 and MW-10 through MW-
12, and the method of construction activities proposed (i.e., drilling), there is limited potential to
encounter archaeological resources at these sites. As discussed above, historical aerials and archival
research suggests that it is possible that the Chinese American Cemetery resource is mapped further
south than what is captured in CCIC records, west and outside of the monitoring well location. The
alternative location believed to be the true location of resource of the Chinese American Cemetery
is a developed area outside of the treatment well site and monitoring well locations. Although the
treatment well site has been previously disturbed, the treatment well site is nevertheless
6 SLF search results do not provide details on cultural resources and are based on the township, range, and section information for a
project site rather than a precise location; therefore, the exact location and nature of the cultural resource is unknown.
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considered sensitive for archaeological resources, consistent with the City’s Archaeological Resource
Preservation Program Guidelines and Conservation and Open Space Element. If project related
construction activities were to interfere with subsurface archaeological resources, this would be a
potentially significant impact.
Mitigation Measures
CUL-1 Workers Environmental Awareness Program Training
All construction personnel and monitors who are not trained archaeologists shall be briefed
regarding unanticipated discoveries prior to the start of construction activities. A basic presentation
shall be prepared and presented by a qualified archaeologist and Chumash Tribal Representative to
inform all personnel working on the project about the archaeological sensitivity of the area. The
purpose of the WEAP training is to provide specific details on the kinds of archaeological materials
that may be identified during construction of the project and explain the importance of and legal
basis for the protection of significant archaeological resources. Each worker shall also learn the
proper procedures to follow in the event that archaeological resources or human remains are
uncovered during ground-disturbing activities. These procedures include work curtailment or
redirection, and the immediate contact of the on-call archaeologist and if appropriate, Native
American representatives. The necessity of training attendance shall be stated on all construction
plans and the City of San Luis Obispo shall maintain records demonstrating construction worker
WEAP participation.
CUL-2 Archaeological and Native American Monitoring
Prior to any ground disturbing activities, the project proponent shall retain an archaeologist meeting
the Secretary of the Interior’s Qualifications Standards (NPS 1983) (Qualified Archaeologist) to
oversee the implementation of this measure.
Prior to any ground disturbing activities, the archaeologist shall provide a Cultural Resources
Mitigation and Monitoring Plan (CRMMP) for review and approval by the City of San Luis Obispo.
The CRMMP should include, but not be limited to, the following:
a. A list of personnel involved in the monitoring activities;
b. Description of Native American involvement;
c. Description of how the monitoring shall occur;
d. Description of location and frequency of monitoring (e.g., full time, part time, spot
checking);
e. Description of what resources may be encountered;
f. Description of circumstances that would result in the halting of work at the project site;
g. Description of procedures for halting work on the site and notification procedures;
h. Description of monitoring reporting procedures; and
i. Provide specific, detailed protocols for what to do in the event of the discovery of human
remains.
The Qualified Archaeologist shall provide conditional monitoring as well as on call response in the
case of an inadvertent discovery of archaeological resources. Given the developed nature of
monitoring well locations MW-01 through MW-08 and MW-10 through MW-12, and the method of
construction activities proposed (i.e., drilling), monitoring at these locations should be limited to
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Final Initial Study – Mitigated Negative Declaration 43
spot-checking and periodic examination of soils through selective sampling of soils brought to the
surface as a result of the drilling activities. All construction-related ground disturbances, including
clearing/grubbing and drilling, within the treatment well site, west and east of U.S. 101) and west of
San Luis Obispo Creek be monitored by an archaeologist and a Native American representative. In
general, archaeological, and Native American monitoring shall be limited to initial ground
disturbance, which is defined as construction-related earthmoving of sediments from their native
place of deposition and does not include any secondary movement of sediment that might be
required for the project. The Qualified Archaeologist may adjust monitoring efforts as needed
(increase, decrease, or discontinue monitoring frequency) based on the observed potential for
construction activities to encounter archaeological deposits. The Qualified Archaeologist shall be
responsible for maintaining daily monitoring logs.
Throughout the course of project construction activities, if a discovery is made by construction
personnel and a monitor is not present, the protocols and procedures outlined in the Mitigation
Measure CUL-3, Unanticipated Discovery of Archaeological Resources, shall be followed. Following
the completion of construction, the Qualified Archaeologist shall prepare an archaeological
monitoring report for submittal to the City and the CCIC with the results of the archaeological
monitoring program.
CUL-3 Unanticipated Discovery of Archaeological Resources
In the event that archaeological remains are encountered during construction, City staff shall be
notified and all work within 50 feet of the find shall be halted until the find is evaluated by the
Qualified Archaeologist or other designated archaeologist working under the direction of the
Qualified Archaeologist and appropriate mitigation, if necessary, is implemented. Native American
tribal representatives shall be notified. If archaeological remains are identified, the resource shall be
evaluated for significance under City Archaeological Resource Preservation Program Guidelines, and
further treatment measures, including but not limited to avoidance consistent with City General
Plan Policies, Phase 2 Subsurface Archaeological Resource Evaluation, or Phase 3 Archaeological
Data Recovery Excavation may be required. Work within 50 feet of the find shall not resume until
authorization is received from the City. This measure shall be included on all construction plans.
Significance After Mitigation
Implementation of Mitigation Measures CUL-1, CUL-2, and CUL-3 would ensure construction
personnel are informed of subsurface conditions and procedures are followed, such as halt of
construction work, retaining a qualified archaeological and native American monitor, and if
necessary, resource recovery. Adherence to Mitigation Measures CUL-1 through CUL-3 would
reduce the project’s impact on archaeological resources to a less than significant level.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
c. Would the project disturb any human remains, including those interred outside of formal
cemeteries?
Known prehistoric and historic period burials within or outside of formal cemeteries were identified
within a 0.5-mile of the 22-acre site and within areas of proposed monitoring wells as a result of the
CHRIS records search, literature review, and background research. According to the CRTC, a “Burial
Sensitivity Area” overlaps with one of the monitoring well locations. As a result, due to the
prehistoric and historical presence of Native Americans within the project area, including
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documented burials within the 0.5-mile records search area, the project’s proximity to Mission San
Luis Obispo, and the Chinese American cemetery identified within CCIC records, there is a potential
to encounter previously unknown or yet identified human remains during project construction
activities.
In the event that human remains are inadvertently encountered during ground disturbing activities,
they would be treated consistent with state and local regulations including California Health and
Safety Code Section 7050.5, California Public Resources Code Section 5097.98, and the California
Code of Regulations Section 15064.5(e). In accordance with these regulations, if human remains are
found, the County Coroner must immediately notified of the discovery. No further disturbance
would occur until the County Coroner has made a determination of origin and disposition pursuant
to Public Resources Code Section 5097.98. If the County Coroner determines that the remains are,
or believed to be Native American origin, the County Coroner is required to notify the NAHC, who in
turn notifies those persons believed to be the most likely descendant (MLD). The MLD has 48 hours
from being granted site access to make recommendations for the disposition of the remains. If the
MLD does not make recommendations within 48 hours, the City would reinter the remains in an
area of the property secure from subsequent disturbance. Compliance with California Health and
Safety Code Section 7050.5, California Public Resources Code Section 5097.98, and the California
Code of Regulations Section 15064.5(e) would ensure the project would have a less than significant
impact related to the disturbance of human remains.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
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6 Energy
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Result in a potentially significant
environmental impact due to wasteful,
inefficient, or unnecessary consumption
of energy resources, during project
construction or operation? □ □ ■ □
b. Conflict with or obstruct a state or local
plan for renewable energy or energy
efficiency? □ □ ■ □
Environmental Setting
Energy consumption is directly related to environmental quality in that the consumption of
nonrenewable energy resources releases criteria air pollutant and greenhouse gas (GHG) emissions
into the atmosphere. Energy use during construction work would be in the form of fuel
consumption (e.g., gasoline and diesel fuel) to operate construction equipment. The City’s
Conservation and Open Space Element and Climate Action Plan contain goals and policies primarily
related to reducing operational energy, including introduction of solar power, implementation of
energy conservation features in buildings, and implementation of carbon-sequestration measures
(City of San Luis Obispo 2014b; City of San Luis Obispo 2020a).
The environmental impacts of air pollutant and GHG emissions associated with the project’s energy
consumption are discussed in detail in Section 3, Air Quality, and Section 8, Greenhouse Gas
Emissions.
Impact Analysis
a. Would the project result in a potentially significant environmental impact due to wasteful,
inefficient, or unnecessary consumption of energy resources, during project construction or
operation?
Energy use during construction would be temporary for the duration of project construction activity.
Construction contractors would be required to comply with the provisions of California Code of
Regulations Title 13 Sections 2449 and 2485, which prohibit off-road diesel vehicles and diesel-
fueled commercial motor vehicles, respectively, from idling for more than five minutes and would
minimize unnecessary fuel consumption. Construction equipment would be subject to the United
States Environmental Protection Agency (USEPA) Construction Equipment Fuel Efficiency Standard
which would also minimize inefficient, wasteful, or unnecessary fuel consumption. Construction
contractors would be required to utilize fuel-efficient equipment consistent with state regulations
and would comply with state measures to ensure that inefficient, wasteful, or unnecessary
consumption of energy does not occur. Operation of the proposed project would require minimal
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Energy
Final Initial Study – Mitigated Negative Declaration 47
energy in the form of electricity to power monitoring and treatment systems in addition to gasoline
use for vehicle trips to the well sites. This minimal energy use would not be wasteful, inefficient, or
unnecessary as it would be required to ensure proper function of the monitoring and treatment
wells to clean-up and prevent PCE contamination. With adherence to applicable regulations related
to energy efficiency, the proposed project’s impact related to energy use would be less than
significant.
LESS-THAN-SIGNIFICANT IMPACT
b. Would the project conflict with or obstruct a state or local plan for renewable energy or energy
efficiency?
State regulations for energy conservation, such as the California Green Building Standards Code and
California Energy Code, target energy efficiency in the development or renovation of buildings and
would be inapplicable to the proposed project. In addition, the City’s energy-related goals and
policies within the Conservation and Open Space Element and Climate Action Plan have limited
applicability to the project as they focus primarily on energy conservation in buildings, solar design,
achieving carbon-free electricity, and carbon sequestration (City of San Luis Obispo 2014b; City of
San Luis Obispo 2020a). As the proposed buildings are limited to housing treatment equipment and
infrastructure, no State or local plans for renewable energy or energy efficiency would apply to the
proposed project. Therefore, impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
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7 Geology and Soils
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Directly or indirectly cause potential
substantial adverse effects, including the
risk of loss, injury, or death involving:
1. Rupture of a known earthquake
fault, as delineated on the most
recent Alquist-Priolo Earthquake
Fault Zoning Map issued by the
State Geologist for the area or
based on other substantial evidence
of a known fault? □ □ ■ □
2. Strong seismic ground shaking? □ □ ■ □
3. Seismic-related ground failure,
including liquefaction? □ □ ■ □
4. Landslides? □ □ ■ □
b. Result in substantial soil erosion or the
loss of topsoil? □ □ ■ □
c. Be located on a geologic unit or soil that
is unstable, or that would become
unstable as a result of the project, and
potentially result in on- or off-site
landslide, lateral spreading, subsidence,
liquefaction, or collapse? □ □ ■ □
d. Be located on expansive soil, as defined
in Table 18-1-B of the Uniform Building
Code (1994), creating substantial direct
or indirect risks to life or property? □ □ ■ □
e. Have soils incapable of adequately
supporting the use of septic tanks or
alternative wastewater disposal systems
where sewers are not available for the
disposal of wastewater? □ □ □ ■
f. Directly or indirectly destroy a unique
paleontological resource or site or unique
geologic feature? □ ■ □ □
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Final Initial Study – Mitigated Negative Declaration 49
Environmental Setting
The project site is within the southern Coast Range geomorphic province. The Coast Range province
is comprised of sub-parallel northwest-southeast trending faults, folds, and mountain ranges (City of
San Luis Obispo 2014a). According to the California Geological Survey the project site is not within
an Alquist-Priolo Fault Zone or overlay an active earthquake fault, the closest active fault to the
treatment well site is the Los Osos Fault Zone, located approximately one mile northwest (California
Geological Survey 2021). The Safety Element of the City’s General Plan recognizes the treatment
well site as an area having high liquefaction potential (City of San Luis Obispo 2014c). The treatment
well site is not within a landslide hazard zone (City of San Luis Obispo 2014c). Soils underlying the
treatment well site are primarily Salinas silty clay loam soil with zero to two percent slopes (United
States Department of Agriculture [USDA] 2024).
Impact Analysis
a.1. Would the project directly or indirectly cause potential substantial adverse effects, including the
risk of loss, injury, or death involving rupture of a known earthquake fault, as delineated on the
most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the
area or based on other substantial evidence of a known fault?
a.2. Would the project directly or indirectly cause potential substantial adverse effects, including the
risk of loss, injury, or death involving strong seismic ground shaking?
a.3. Would the project directly or indirectly cause potential substantial adverse effects, including the
risk of loss, injury, or death involving seismic-related ground failure, including liquefaction?
a.4. Would the project directly or indirectly cause potential substantial adverse effects, including the
risk of loss, injury, or death involving landslides?
c. Would the project be located on a geologic unit or soil that is unstable, or that would become
unstable as a result of the project, and potentially result in on- or off-site landslide, lateral
spreading, subsidence, liquefaction, or collapse?
d. Would the project be located on expansive soil, as defined in Table 18-1-B of the Uniform
Building Code (1994), creating substantial direct or indirect risks to life or property?
Individual well installation activities would include drilling to a maximum of 200 feet and would not
create conditions that would exacerbate unstable seismic conditions or stresses in the Earth’s crust.
Although the well locations are located near seismically active areas such as the Los Osos Fault
Zone, the project does not include development of occupiable buildings or infrastructure, thereby
exposing persons to geologic or soil related hazards, including ground shaking, fault rupture, lateral
spreading, subsidence, soil expansivity, landside, liquefaction or collapse. While there is a potential
for disturbance of the proposed water and wastewater distribution lines during a major seismic
event, the project would be designed to minimize the potential hazard and the City would
implement standard emergency protocols to minimize any related potential hazards due to pipe
displacement. Therefore, potential impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
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b. Would the project result in substantial soil erosion or the loss of topsoil?
Each monitoring well would consist of one 2-inch or 4-inch diameter well. Due to the minimal
ground disturbance required for drilling and installation of a 2-inch or 4-inch diameter well, there is
no potential for monitoring well drilling to result in substantial erosion or siltation. As the overall
footprint of construction activities, including work at the treatment well site, would exceed one
acre, the project would be required to comply with the Construction Stormwater General Permit,
adopted by the SWRCB. This State requirement was developed to ensure that stormwater is
managed, and that erosion is controlled on construction sites. The Construction Stormwater General
Permit requires preparation and implementation of a Storm Water Pollution Prevention Plan
(SWPPP), which requires implementation of BMPs to control stormwater run-on and runoff from
construction work sites. The project would also be required to comply with the City’s standard BMPs
for erosion and sedimentation control (as required by the City’s adopted Standard Specifications
and Engineering Standards). BMPs may include, but would not be limited to, physical barriers to
reduce erosion and sedimentation, construction of sedimentation basins, limitations on work
periods during storm events, use of infiltration swales, protection of stockpiled materials, and a
variety of other measures to be identified by a qualified SWPPP developer that would substantially
reduce erosion from occurring during construction. With adherence to the Construction Stormwater
General Permit and the City’s mandatory Engineering Standards and Specifications, the project
would have a less than significant impact related to soil erosion.
LESS-THAN-SIGNIFICANT IMPACT
e. Would the project have soils incapable of adequately supporting the use of septic tanks or
alternative wastewater disposal systems where sewers are not available for the disposal of
wastewater?
The project would not include or require the use of septic tanks or alternative wastewater disposal
systems. On-site portable restroom facilities would be provided by the construction contractor for
workers operating at the site. No impact would occur.
NO IMPACT
f. Would the project directly or indirectly destroy a unique paleontological resource or site or
unique geologic feature?
Paleontological resources, or fossils, are the evidence of once-living organisms preserved in the rock
record. Such resources include both the fossilized remains of ancient plants and animals and the
traces of such remains. Paleontological resources are not found in “soil” but are rather found in the
geologic deposits or bedrock that underlies the soil layer. Typically, fossils are greater than 5,000
years old (i.e., older than middle Holocene in age) and preserved in sedimentary rocks. Although
rare, fossils can also be preserved in volcanic rocks or low-grade metamorphic rocks under certain
conditions (Society of Vertebrate Paleontology [SVP] 2010). Fossils often occur in an unpredictable
distribution within some sedimentary units.
Ground disturbing activities associated with the monitoring wells include drilling a 10-inch diameter
hole to install the wells. Only soil cuttings would be derived from the drilling; no underlying
geological units would be excavated. Soil cuttings do not produce geological materials with the
potential to discover or identify fossils. Accordingly, paleontological monitoring of monitoring well
installation could not result in quantitative or qualitative evaluations of potential paleontological
resources. As defined by SVP (2010), a fossil’s significance is tied directly to its scientific value; as
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Final Initial Study – Mitigated Negative Declaration 51
such, fossils that would not be exposed during project activity or reasonably could be anticipated to
be exposed as a result of future human or natural events lack the access to scientific inquiry
necessary to be found as significant under CEQA. Therefore, because no known paleontological
resources would be impacted and any undiscovered resources would not otherwise be
encountered, ground disturbing activities at the monitoring wells would have a less than significant
impact on paleontological resources.
Ground disturbing activities at the treatment well site would involve drilling as well as grading to
install utility infrastructure and gravel access roads. According to mapping by Jennings (1958), the
treatment well site is underlain by Quaternary-aged alluvium (Jennings 1958). Similar to the
discussion of monitoring well drilling, drilling treatment well TW-4 would have a less than significant
impact on paleontological resources. Other ground disturbing activities at the treatment well site
are not anticipated to reach depths where older, potentially more sensitive sediments could be
encountered. However, the possibility remains that unanticipated paleontological resources could
be discovered during ground-disturbing activities at the treatment well site. Therefore, this impact
would be potentially significant.
Mitigation Measure
GEO-1 Unanticipated Discovery of Paleontological Resources
In the event of a fossil discovery by construction personnel at the treatment well site, the
construction contractor shall halt all construction activities within the 50 feet of the fossil, and a
Qualified Professional Paleontologist shall be retained to evaluate the find prior to resuming
construction activity. If it is determined the fossil(s) is (are) scientifically significant, the Qualified
Professional Paleontologist shall complete the following conditions to mitigate impacts to significant
fossil resources:
Fossil Salvage. If fossils are discovered, the Qualified Professional Paleontologist shall have the
authority to halt or temporarily divert construction equipment within 50 feet of the find until
the Qualified Professional Paleontologist evaluate the discovery and determine if the fossil may
be considered significant. Bulk matrix sampling may be necessary to recover small invertebrates
or microvertebrates from within paleontologically sensitive deposits.
Fossil Preparation and Curation. Once salvaged, significant fossils shall be identified to the
lowest possible taxonomic level, prepared to a curation-ready condition, and curated in a
scientific institution with a permanent paleontological collection along with all pertinent field
notes, photos, data, and maps. Fossils of undetermined significance at the time of collection
may also warrant curation at the discretion of the Qualified Professional Paleontologist.
Final Paleontological Report. The Qualified Professional Paleontologist shall submit a report
describing the results of the paleontological monitoring efforts associated with the project. The
report shall include a summary of the field and laboratory methods, an overview of the project
geology and paleontology, a list of taxa recovered (if any), an analysis of fossils recovered (if
any) and their scientific significance, and recommendations. The report shall be submitted to
the City.
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Significance After Mitigation
Mitigation Measure GEO-1 describes procedures that shall be followed in the event an
unanticipated paleontological resource is encountered during construction at the treatment well
site. With implementation of Mitigation Measure GEO-1, potential impacts to paleontological
resources would be reduced to a less than significant level.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
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8 Greenhouse Gas Emissions
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Generate greenhouse gas emissions,
either directly or indirectly, that may
have a significant impact on the
environment? □ □ ■ □
b. Conflict with an applicable plan, policy, or
regulation adopted for the purpose of
reducing the emissions of greenhouse
gases? □ □ ■ □
Environmental Setting
The principal state GHG reduction plans and policies are Assembly Bill (AB) 32, the California Global
Warming Solutions Act of 2006, and the subsequent legislation, Senate Bill (SB) 32 and AB 1279. The
goal of SB 32 is to reduce GHG emissions to 40 percent below 1990 levels by 2030. In 2022, the
State passed AB 1279, which declares the State would achieve net-zero GHG emissions by 2045 and
would reduce GHG emissions by 85 percent below 1990 levels by 2045. To implement these
requirements, CARB has published the 2022 Scoping Plan, which focuses on outcomes needed to
achieve carbon neutrality by assessing paths for clean technology, energy deployment, natural and
working lands, and others, and is designed to meet the state’s long-term climate objectives and
support a range of economic, environmental, energy security, environmental justice, and public
health priorities (CARB 2022).
SLOAPCD has developed GHG thresholds of significance through 2045 in accordance with Assembly
Bill 1279 and the California Air Resource Board’s 2022 Scoping Plan, which set forth a goal of
reducing GHG emissions by 85 percent below 1990 levels no later than 2045 (SLOAPCD 2023).
Pursuant to SLOAPCD guidance, projects which result in less than 830 metric tons of carbon dioxide
equivalent7 (MT CO2e) per year in 2026 would have a less than significant impact related to GHG
emissions.
In 2020, the City adopted a Climate Action Plan, which establishes 2030 GHG emissions targets and
a carbon neutrality target by 2035 (City of San Luis Obispo 2020a).
7 Carbon dioxide equivalent is a unit of measurement used to standardize the climate effects of various GHGs in terms of the amount of
carbon dioxide that would create the same amount of global warming.
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Final Initial Study – Mitigated Negative Declaration 55
Impact Analysis
a. Would the project generate GHG emissions, either directly or indirectly, that may have a
significant impact on the environment?
Based on the results of the CalEEMod modeling (Appendix A), construction of all components of the
proposed project would generate approximately 842 MT CO2e. Amortized over a 30-year period,
construction of the project would generate approximately 28 MT CO2e per year. This level of GHG
emission does not exceed SLOAPCD’s annual threshold of 830 MT CO2e. Therefore, construction of
the proposed project would have a less than significant impact related to GHG emissions.
Operation of the project would generate a nominal amount of GHG emissions from electricity
consumption to operate the treatment wells and occasional vehicle trips to the monitoring and
treatment well sites for maintenance activities, which would not have the potential to exceed
SLOAPCD GHG emissions thresholds. Therefore, the proposed project would have a less than
significant impact related to GHG emissions.
LESS-THAN-SIGNIFICANT IMPACT
b. Would the project conflict with an applicable plan, policy, or regulation adopted for the purpose
of reducing the emissions of greenhouse gases?
The City adopted a Climate Action Plan in 2020 with a goal of carbon neutrality by 2035. Since the
release of the City’s Climate Action Plan, the State adopted AB 1279, which sets a goal of achieving
statewide carbon neutrality by 2045. Although the City’s Climate Action Plan was released prior to
the adoption of AB 1279, because the Climate Action Plan sets a carbon neutrality goal consistent
with statewide efforts to achieve carbon neutrality, the Climate Action Plan is consistent with the AB
1279 carbon neutrality targets. Therefore, for the purposes of this analysis, the City’s Climate Action
Plan is the applicable plan for the project. Appendix C of the City’s Climate Action Plan includes
thresholds and guidance for preparation of GHG emissions analyses for projects within the city. To
support progress toward the City’s carbon neutrality goal, projects in San Luis Obispo must
demonstrate consistency with the Climate Action Plan.
Table 5 summarizes the proposed project’s consistency with the City’s Climate Action Plan, based on
applicable GHG Emissions Compliance Checklist measures (City of San Luis Obispo 2020a). As
described therein, the proposed project would not conflict with the Climate Action Plan. Therefore,
this impact would be less than significant.
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Table 5 Project Consistency with the Climate Action Plan
Climate Action Plan Measures Project Consistency
Pillar 4: Connected Community
6a. Is the estimated Project/Plan-generated Vehicle Miles
Traveled (VMT) within the City’s adopted thresholds, as
confirmed by the City’s Transportation Division?
Consistent. Trips associated with the proposed project
would not exceed the City’s 110 trip per day threshold of
significance. For more information, refer to Section 17,
Transportation.
Pillar 6: Natural Solutions
9. Does the Project/Plan comply with Municipal Code
requirements for trees?
Consistent. The project would remove seven trees to
install the access road and utility infrastructure. Tree
removal would occur consistent with the requirements of
Chapter 12.24 of the City’s Municipal Code, including
compensatory tree planting (minimum 1:1 ratio). There is
adequate area within the City-owned parcel proposed for
the treatment well site to accommodate the
compensatory plantings. All proximate trees proposed to
remain would be avoided and preserved pursuant to the
City’s mandatory Standard Specifications and Engineering
Standards for tree protection.
Source: City of San Luis Obispo 2020a
LESS-THAN-SIGNIFICANT IMPACT
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Environmental Checklist
Greenhouse Gas Emissions
Final Initial Study – Mitigated Negative Declaration 57
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9 Hazards and Hazardous Materials
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Create a significant hazard to the public
or the environment through the routine
transport, use, or disposal of hazardous
materials? □ □ ■ □
b. Create a significant hazard to the public
or the environment through reasonably
foreseeable upset and accident
conditions involving the release of
hazardous materials into the
environment? □ □ ■ □
c. Emit hazardous emissions or handle
hazardous or acutely hazardous
materials, substances, or waste within
0.25 mile of an existing or proposed
school? □ □ ■ □
d. Be located on a site that is included on a
list of hazardous material sites compiled
pursuant to Government Code Section
65962.5 and, as a result, would it create a
significant hazard to the public or the
environment? □ □ ■ □
e. For a project located in an airport land
use plan or, where such a plan has not
been adopted, within two miles of a
public airport or public use airport, would
the project result in a safety hazard or
excessive noise for people residing or
working in the project area? □ □ ■ □
f. Impair implementation of or physically
interfere with an adopted emergency
response plan or emergency evacuation
plan? □ □ ■ □
g. Expose people or structures, either
directly or indirectly, to a significant risk
of loss, injury, or death involving wildland
fires? □ □ ■ □
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Hazards and Hazardous Materials
Final Initial Study – Mitigated Negative Declaration 59
Environmental Setting
The following databases were reviewed in July 2024 for known hazardous material contamination at
the treatment well site:
The SWRCB Geotracker database
The California Department of Toxic Substances Control’s (DTSC) EnviroStor database
The Superfund Enterprise Management System (SEMS) database
The treatment well site does not appear on any hazardous material site list compiled pursuant to
Government Code Section 65962.5 (DTSC 2024; SWRCB 2024a; U.S. EPA 2024). The treatment well
site is located within the San Luis Obispo County Regional Airport Land Use Plan, inside Zone 6,
Traffic Pattern Zone (RS&H 2021). There are no schools within 0.25-mile of the treatment well site.
The monitoring wells are not located on a hazardous material site list compiled pursuant to
Government Code Section 65962.5 (DTSC 2024; SWRCB 2024a; U.S. EPA 2024). The closest
hazardous materials sites to the monitoring wells are located approximately 320 feet west of MW-
01, 280 feet west of MW-02, 300 feet west of MW-03, and 150 feet north of MW-05. The sites
located proximate to MW-01, MW-03, and MW-05 are identified as “Completed- Case Closed”
which means site investigation and remedial action has been completed, and the Central Coast
Regional Water Quality Control Board determined no further action was required (SWRCB 2024a).
The site 280 feet west of MW-02, the South Higuera Street and Pismo Street Pipeline, is case open
for verification monitoring, meaning that remediation has been completed and monitoring of the
site has continued to ensure no further action is required (SWRCB 2024b). MW-04, MW-05, MW-07,
MW-09, MW-10, MW-11, and MW-12 are located within the San Luis Obispo County Regional
Airport Land Use Plan, inside Zone 6, Traffic Pattern Zone (RS&H 2021). MW-08 is located
approximately 0.25-mile southeast of Pacific Beach High School.
Impact Analysis
a. Would the project create a significant hazard to the public or the environment through the
routine transport, use, or disposal of hazardous materials?
b. Would the project create a significant hazard to the public or the environment through
reasonably foreseeable upset and accident conditions involving the release of hazardous
materials into the environment?
c. Would the project emit hazardous emissions or handle hazardous or acutely hazardous
materials, substances, or waste within 0.25 mile of an existing or proposed school?
The project would not involve the routine use or disposal of hazardous materials, as project
activities would only last the duration of the construction phase (approximately 120 working days),
and no permanent project features would involve the operational use or disposal of hazardous
materials. There are no schools within 0.25-mile of the treatment well site. MW-08 is located
approximately 0.25-mile southeast of Pacific Beach High School.
Construction equipment would require the use of diesel fuel, gasoline, motor oil, and other similar
materials. Wastes derived from well installation and well development activities would include soil
cuttings, decontamination water, and development water. Pursuant to Title 22 of the California
Code of Regulations, the construction contractor would be required to submit samples of drilling
spoils for analytical testing required for waste profiling. Based on the results of the analytical
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60
testing, soil cuttings and water would be containerized in 55-gallon drums, temporarily stored on-
site or at an appropriate location, and profiled for disposal; derived wastes would be transported
off-site and disposed of at an appropriate disposal facility.
These materials would be properly handled and disposed of in accordance with applicable
regulations. Construction personnel would be required to have the necessary training and/or
certifications to operate equipment used during project activities, minimizing the risk of accidental
release of hazardous materials due to equipment failure. The project would not increase,
encourage, or otherwise facilitate the transportation of hazardous materials above existing
conditions. The amount of fuels and oil to power construction equipment would be typical of similar
projects. The GAC media is designed to adsorb contaminants, including PCE during treatment. Once
the media is spent, as observed by the presence of PCE at the middle point of the treatment system
during routine water sampling, a GAC media exchange will be scheduled. The City will work with a
qualified vendor to supply new media and dispose of the spent media. Disposal options for GAC
include profiling and disposal at an Environmental Protection Agency (EPA)-approved landfill,
incineration, or regeneration. Due to the relatively low PCE concentrations, it is anticipated that
approximately one bed (20,000 pounds) of GAC will need to be disposed of annually. and nNo
significant long-term operational impacts related to the routine transport, handling, or disposal of
hazardous materials would result from the project.
Therefore, the project would not create a significant hazard to the public or environment through
the routine transport, use, or disposal of hazardous materials, through reasonably foreseeable upset
and accident conditions involving the release of hazardous materials, or through use of hazardous
materials within 0.25-mile of a school. These impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
d. Would the project be located on a site that is included on a list of hazardous material sites
compiled pursuant to Government Code Section 65962.5 and, as a result, would it create a
significant hazard to the public or the environment?
The treatment well site is not included on any lists of hazardous materials compiled pursuant to
Government Code Section 65962.5 (DTSC 2024; SWRCB 2024a; U.S. EPA 2024).
Therefore, the project would not create a significant hazard to the public or environment due to
being located on a hazardous materials site compiled pursuant to Government Code Section
65962.5. No impact would occur. The site 280 feet west of MW-02, the South Higuera Street and
Pismo Street Pipeline, is case open for verification monitoring, meaning that remediation has been
completed and monitoring of the site has continued to ensure no further action is required (SWRCB
2024b). Due to the nature of construction at MW-02, temporary drilling lasting approximately 120
days would not have the potential to create a significant hazard to the public. As described in
Thresholds 9 (a)(b)(c), the construction contractor would be required to submit samples of drilling
spoils for analytical testing required for waste profiling transported off-site and disposed of at an
appropriate disposal facility. Therefore, any potentially contaminated soil from the hazardous
materials site 280 feet west of MW-02 would be safely disposed. MW-02 would be operated
remotely and would not continuously introduce the public to significant hazards. Therefore, this
impact would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
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Environmental Checklist
Hazards and Hazardous Materials
Final Initial Study – Mitigated Negative Declaration 61
e. For a project located within an airport land use plan or, where such a plan has not been
adopted, within two miles of a public airport or public use airport, would the project result in a
safety hazard or excessive noise for people residing or working in the project area?
The closest airport to the project site is the San Luis Obispo County Regional Airport, approximately
1.5 miles southeast of the treatment well site. Although the treatment well site is located in the
Traffic Pattern Zone, the project includes the installation of subsurface monitoring wells associated
with the treatment of groundwater. The project does not include development of habitable
structures and, therefore, would not continuously expose workers to airport noise. Temporary
project workers at the treatment well site would only be required during the length of the
construction period (approximately 120 working days) or routine operational maintenance. As such,
the project would not result in a safety hazard or excessive noise for working at the project site. This
impact would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
f. Would the project impair implementation of or physically interfere with an adopted emergency
response plan or emergency evacuation plan?
Construction at the treatment wells would not involve interference with roadways. Construction of
a majority of the monitoring wells would be located adjacent to and within existing roadways which
could pose temporary interference with roadways due to staging of construction equipment.
Pursuant to the City’s Specifications and Engineering Standards, the construction contractor would
be required to create a temporary traffic control plan that adheres to standards for emergency
access in order to allow construction staging areas into the street network (City of San Luis Obispo
2020b). The traffic control plan would address required equipment, barricading, flagmen, use of
pilot vehicles, signing, tapers, and other components required to maintain traffic circulation. The
traffic control plan is required to address how traffic would be routed, including traffic from cross
streets, alleys, and private driveways. The traffic control plan would be subject to the approval of
the City Engineer prior to the start of construction activities. With development and implementation
of the traffic control plan, the project would not interfere with traffic management such that it
would conflict with City emergency response or evacuation plans. The project would not conflict
with adopted emergency response plan or emergency evacuation plan. This impact would be less
than significant.
LESS-THAN-SIGNIFICANT IMPACT
g. Would the project expose people or structures, either directly or indirectly, to a significant risk
of loss, injury, or death involving wildland fires?
The project site is located within a Local Responsibility Area and are not within a Very High Fire
Hazard Severity Zone, as defined by the California Department of Forestry and Fire Protection (CAL
FIRE) (CAL FIRE 2024). California Public Resources Code Section 4442 mandates the use of spark
arrestors, which prevent the emission of flammable debris from exhaust on earth-moving and
portable construction equipment with internal combustion engines that are operating on any forest-
covered, brush-covered, or grass-covered land. California Public Resources Code Section 4428
requires construction contractors to maintain fire suppression equipment during the highest fire
danger period (April 1 to December 1) when operating on or near any forest-covered, brush-
covered, or grass-covered land. Pursuant to compliance with this existing regulation, the project
would not expose people or structures, directly or indirectly, to a significant risk of loss, injury, or
death involving wildland fires. This impact would be less than significant.
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City of San Luis Obispo
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62
LESS-THAN-SIGNIFICANT IMPACT
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Environmental Checklist
Hydrology and Water Quality
Final Initial Study – Mitigated Negative Declaration 63
10 Hydrology and Water Quality
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Violate any water quality standards or
waste discharge requirements or
otherwise substantially degrade surface
or ground water quality? □ □ ■ □
b. Substantially decrease groundwater
supplies or interfere substantially with
groundwater recharge such that the
project may impede sustainable
groundwater management of the basin? □ □ ■ □
c. Substantially alter the existing drainage
pattern of the site or area, including
through the alteration of the course of a
stream or river or through the addition of
impervious surfaces, in a manner which
would:
(i) Result in substantial erosion or
siltation on- or off-site; □ □ ■ □
(ii) Substantially increase the rate or
amount of surface runoff in a
manner which would result in
flooding on- or off-site; □ □ ■ □
(iii) Create or contribute runoff water
which would exceed the capacity of
existing or planned stormwater
drainage systems or provide
substantial additional sources of
polluted runoff; or □ □ ■ □
(iv) Impede or redirect flood flows? □ □ ■ □
d. In flood hazard, tsunami, or seiche zones,
risk release of pollutants due to project
inundation? □ □ □ ■
e. Conflict with or obstruct implementation
of a water quality control plan or
sustainable groundwater management
plan? □ □ ■ □
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City of San Luis Obispo
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64
Environmental Setting
The San Luis Obispo Creek watershed is an approximately 53,271-acre coastal basin in southern San
Luis Obispo County, which rises to an elevation of about 2,500 feet above sea level in the Santa
Lucia Range. San Luis Obispo Creek flows to the Pacific Ocean and has six major tributary basins:
Stenner Creek, Prefumo Creek, Laguna Lake, East Branch San Luis Obispo Creek, Davenport Creek,
and See Canyon. The creek flows through the City and empties into the Pacific Ocean just west of
Avila Beach.
The City of San Luis Obispo is not subject to inundation from tsunami or seiche (City of San Luis
Obispo 2014c). The treatment well site is not located in a Special Flood Hazard Area, but is located
in an “Other Area of Flood Hazard” identified with a 0.2 percent annual chance flood hazard; areas
of one percent annual chance flood with average depth less than one foot or with drainage areas of
less than one square mile (FEMA 2024).
In 2015, the state legislature approved the Sustainable Groundwater Management Act (SGMA).
SGMA requires governments and water agencies of high and medium priority basins to halt
overdraft and bring groundwater basins into balanced levels of pumping and recharge. Under
SGMA, these basins should reach sustainability within 20 years of implementing their sustainability
plans. The project is located within the San Luis Obispo Valley Groundwater Basin, which has been
designated by the California Department of Water Resources (DWR) as a high-priority basin (DWR
2022). The County and City formed Groundwater Sustainability Agencies (GSAs) within their
respective jurisdictions to ensure full compliance with SGMA throughout the entire San Luis Obispo
Valley Groundwater Basin. The City is the GSA with jurisdiction over the well locations (City of San
Luis Obispo Department of Public Works 2022).
Groundwater is not currently used for the City’s drinking water supply. While the City does not
currently receive drinking water from the San Luis Obispo Valley Groundwater Basin, it had
previously maintained a network of production wells for drinking and irrigation use. While those
wells are no longer in use, the sustainable management of the Basin as described in the San Luis
Obispo Valley Basin Groundwater Sustainability Plan includes provisions for the use of groundwater
by the City. As part of the GSP, a water budget was developed to evaluate water inflow and outflow.
The San Luis Valley subarea of the Basin has an estimated surplus of 700 acre-feet per year (AFY).
The project was initiated to characterize a PCE plume within the San Luis Valley Subarea of the San
Luis Obispo Valley Groundwater Basin, DWR Bulletin 118 Basin No. 3-09 (Basin), in San Luis Obispo
County.
Impact Analysis
a. Would the project violate any water quality standards or waste discharge requirements or
otherwise substantially degrade surface or ground water quality?
As stormwater flows over a construction site, it can pick up sediment, debris, and chemicals and
transport them to receiving water bodies. Additionally, soil disturbance during project construction
would increase the potential for erosion and sedimentation. Construction of the monitoring wells
would require minimal construction activities limited to linear drilling at one location for each
monitoring well, precluding the possibility of erosion. Construction at the treatment well site would
involve excavation for utility installation in addition to surface work to construct foundations for the
buildings, GAC vessels, and storage tanks, and the gravel access roads. As described in Threshold
7(b), construction would be required to comply with the Construction Stormwater General Permit,
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Environmental Checklist
Hydrology and Water Quality
Final Initial Study – Mitigated Negative Declaration 65
which mandates preparation and implementation of a SWPPP and associated BMPs to control
stormwater run-on and runoff from construction work sites. The project is also required to comply
with the City’s standard BMPs for erosion and sedimentation control (as required by the City’s
adopted Standard Specifications and Engineering Standards). BMPs may include, but would not be
limited to, physical barriers to reduce erosion and sedimentation, construction of sedimentation
basins, limitations on work periods during storm events, use of infiltration swales, protection of
stockpiled materials, and a variety of other measures to be identified by a qualified SWPPP
developer that would substantially reduce erosion from occurring during construction. At the
completion of construction, the project would not introduce stormwater pollutants. With adherence
to these regulations, project construction would have a less than significant impact related to
violating water quality standards or waste discharge requirements.
LESS-THAN-SIGNIFICANT IMPACT
b. Would the project substantially decrease groundwater supplies or interfere substantially with
groundwater recharge such that the project may impede sustainable groundwater
management of the basin?
The purpose of the project is to improve water quality, through clean-up of existing PCE
contamination within in the San Luis Valley Subarea of the San Luis Obispo Valley Groundwater
Basin, and to expand local water supply resiliency by reducing reliance on local surface water
supplies. As part of the GSP, a water budget was developed to evaluate water inflow and outflow.
The San Luis Valley subarea of the Basin has an estimated surplus of 700 acre-feet per year (AFY),
and the GSP identifies the sustainable yield as 2,500 AFY for San Luis Valley. The proposed combined
pumping distribution for the two extraction wells will not exceed 600 AFY, less than the estimated
surplus.
Extraction of groundwater would occur in compliance with SGMA and the approved Groundwater
Sustainability Plan (GSP), and meters would be installed to ensure compliance, consistent with the
City’s requirements to monitor all new wells within the City. The City is required to prepare and
implement an Operations and Maintenance Plan for the proposed groundwater extraction and
water distribution to ensure compliance with DDW regulations, SGMA, and GSP. A component of
this plan includes groundwater level and pumping monitoring at the extraction/treatment wells. The
GSP identifies sustainability indicators (which are used to define undesirable results), including but
not limited to, chronic lowering of groundwater levels, reduction of groundwater storage, land
subsidence, and depletion of interconnected surface water. The GSP includes minimum thresholds
for each sustainability indicator, including an identified groundwater level elevation (96 feet) at a
monitoring well located proximate to San Luis Creek. In addition to the monitoring well identified in
the GSP, the monitoring wells proposed as part of the project will also provide groundwater level
data, and will be equipped with telemetry to monitoring pumping, and allow for automatic
adjustments in pumping rates.
In addition, the proposed pumping strategy may be reduced if monitoring well data indicates
declining PCE concentrations. Pumping volumes will not exceed 600 AFY, and adjustments will be
based on monitoring results and decreasing PCE levels. The California Maximum Contaminant Level
(MCL) for PCE is 5.0 µg/L, which will be used as a cleanup metric when applicable. As the two wells
are intended to provide resiliency, and the primary water supplies for the City would consist of the
existing surface water supplies, the City has the ability to reduce pumping at one or both of the
wells to ensure GSP compliance.
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City of San Luis Obispo
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66
Impervious surfaces would be limited to structural foundations and paving within the protected and
fenced treatment well sites (approximately 0.4 acre). The project is required to comply with City
Standard Specifications and Engineering Standards for post-construction stormwater compliance.
Therefore, based on compliance with existing standards and requirements, including on-going
metering and monitoring of the groundwater extractions, the project would not substantially
decrease groundwater supplies, or substantially interfere with groundwater recharge such that the
project would impede sustainable groundwater management of the basin. Therefore, impacts
would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
c.(i) Would the project substantially alter the existing drainage pattern of the site or area,
including through the alteration of the course of a stream or river or through the addition of
impervious surfaces, in a manner which would result in substantial erosion or siltation on- or
off-site?
c.(ii) Would the project substantially alter the existing drainage pattern of the site or area,
including through the alteration of the course of a stream or river or through the addition of
impervious surfaces, in a manner which would substantially increase the rate or amount of
surface runoff in a manner which would result in flooding on- or off-site?
c.(iii) Would the project substantially alter the existing drainage pattern of the site or area,
including through the alteration of the course of a stream or river or through the addition of
impervious surfaces, in a manner that would create or contribute runoff water which would
exceed the capacity of existing or planned stormwater drainage systems or provide
substantial additional sources of polluted runoff?
c.(iv) Would the project substantially alter the existing drainage pattern of the site or area,
including through the alteration of the course of a stream or river or through the addition of
impervious surfaces, in a manner which would impede or redirect flood flows?
Construction activities would be limited to linear drilling at one location for each monitoring well,
precluding the possibility for exposing soil to erosion or siltation, exacerbating flooding, contributing
excess runoff, or impeding or redirecting flood flows. The monitoring wells would not introduce new
impervious surfaces which have the potential to alter existing drainage patterns which could result
in flooding or increase run off. Once subsurface monitoring wells are installed, a flush-mounted
traffic rated steel well box will be installed over each well. The project would create approximately
0.40 acre of impervious surfaces due to structural foundations and paving within the two treatment
well locations. The project is required to comply with City Standard Specifications and Engineering
Standards for post-construction stormwater compliance. New gravel access roads would be installed
at the TW-3 and TW-4 sites; however, these would not be paved roads and therefore would not
result in additional impervious surfaces. Therefore, the project would not significantly alter the
existing drainage pattern of the site or area. Potential impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
d. In flood ha9zard, tsunami, or seiche zones, would the project risk release of pollutants due to
project inundation?
The City of San Luis Obispo is not subject to inundation from tsunami or seiche and the treatment
well site is not located in a Special Flood Hazard Area. Facilities or construction activities that use or
store large quantities of hazardous materials could harm the environment if inundated by a flood
resulting from a storm event or dam failure. As discussed in Section 9, Hazards and Hazardous
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Environmental Checklist
Hydrology and Water Quality
Final Initial Study – Mitigated Negative Declaration 67
Materials, the project would not involve the routine use or disposal of hazardous materials beyond
the construction period, as project activities would only last the duration of construction
(approximately 120 working days for TW-4 and 50 working days for monitoring wells), and no
permanent features would be constructed that would involve the use or disposal of hazardous
materials. Groundwater contaminated with PCE would be treated and discharged into backwash
tanks, and wastewater would be transported to the City’s sewer system, all within a contained
system. There are no operational components which have the potential to introduce new pollutants
to the project site or result in a change to the existing flood patterns. Since the project would not
risk pollutant release due to project inundation in a flood hazard area, there would be no impact.
NO IMPACT
e. Would the project conflict with or obstruct implementation of a water quality control plan or
sustainable groundwater management plan?
The Water Quality Control Plan for the Central Coast Basin, adopted by the Central Coast Regional
Water Quality Control Board, is the water quality control plan applicable to the project site. The
Basin Plan establishes implementation programs to achieve water quality objectives to protect
beneficial uses. As described in Threshold 10(a), construction of the would be conducted in
compliance with the Construction Stormwater General Permit and the City’s mandatory Standards
Specifications and Engineering Standards to minimize the potential for pollutants to degrade water
quality. Operation of the project would not introduce new stormwater pollutants. Therefore, the
project would not conflict with the water quality objectives within the Water Quality Control Plan
for the Central Coast Basin.
The San Luis Obispo Valley Basin Groundwater Sustainability Plan is the applicable sustainable
groundwater management plan to the project site. As described in Threshold 10(b), the purpose of
the project is to improve water quality, through clean-up and prevention of PCE contamination in
drinking water supply wells in the San Luis Valley Subarea of the San Luis Obispo Valley
Groundwater Basin, and to expand local water supply resiliency by reducing reliance on local surface
water supplies. Extraction of groundwater would occur in compliance with SGMA and the approved
GSP, and meters would be installed to ensure compliance, consistent with the City’s requirements
to monitor all new wells within the City. Therefore, the project would not conflict with or obstruct
implementation of the San Luis Obispo Valley Basin Groundwater Sustainability Plan.
LESS-THAN-SIGNIFICANT IMPACT
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68
11 Land Use and Planning
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Physically divide an established
community? □ □ □ ■
b. Cause a significant environmental impact
due to a conflict with any land use plan,
policy, or regulation adopted for the
purpose of avoiding or mitigating an
environmental effect? □ □ ■ □
Environmental Setting
The 22-acre treatment well site is located in the southern portion of the City along U.S. 101 between
Prado Road and Los Osos Valley Road, the monitoring wells are dispersed on City property or within
City easement or right-of-way. The southern portion of the treatment well site is zoned
Conservation/Open Space (C/OS-20) and has a land use designation of Open Space. The northern
portion is zoned Public Facility (PF) and Public Facility-Special Considerations (PF-S) with a land use
designation of Public. The treatment well site is surrounded by U.S. 101 and commercial
development to the north, the City Water Resource Recovery Facility (WRRF) to the north, San Luis
Obispo Creek and residential development to the north/south.
Monitoring wells would be dispersed on City property or within City easements within the following
zones: Conservation/Open Space (C/OS-20), Medium Density Residential (R-2), Low-Density
Residential Specific Plan Overlay (R-1-SP), Public Facility (PF), Service Commercial (C-S), Service
Commercial Mixed Use Overlay (C-S-MU), Service Commercial Planned Development Overlay (C-S-
PD), Retail Commercial (C-R), Retail Commercial Planned development Overlay (C-R-PD), and Tourist
Commercial (C-T). The monitoring wells are on land designated with the following land uses: Service
and Manufacturing, General Retail, Tourist Commercial, Public, Low Density Residential, Medium
Density Residential, and Open Space.
Impact Analysis
a. Would the project physically divide an established community?
Construction staging for treatment well installation would occur in an area measuring approximately
40 feet by 10 feet to account for the drill rig footprint. As discussed in the Project Description, a 100-
foot buffer is added to the 40 feet by 10 feet to account for the work zone to accommodate the
support and decontamination truck, as well as the work area for the crew. Treatment well
installation would occur in City maintained open space along U.S. 101. Staging for monitoring well
locations would be conducted to maintain local access for residents to the extent practicable in
compliance with temporary traffic control measures specified within the City’s Standard
Specifications & Engineering Standards (City of San Luis Obispo 2020b). All work would occur within
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Environmental Checklist
Land Use and Planning
Final Initial Study – Mitigated Negative Declaration 69
City property or City easement or right-of-way and would be temporary, lasting approximately 120
days for TW-4 and 50 days for monitoring wells. The project would not involve changes in land uses
or the creation of highways or other large-scale development or infrastructure with the potential to
divide an established community. Therefore, no impact would occur.
NO IMPACT
b. Would the project cause a significant environmental impact due to a conflict with any land use
plan, policy, or regulation adopted for the purpose of avoiding or mitigating an environmental
effect?
The project does not propose any land use designation or zoning changes. The purpose of the
project is to monitor water quality and monitor the effectiveness of extracting and treating
impacted groundwater via the installation of treatment wells in an area surrounded by existing
public facility uses, such as the City corporation yard and the WRRF. Monitoring wells would be
dispersed on City property or within City easement or right-of-way. The project would not conflict
with any land use plan, policy, or regulation adopted for the purpose of avoiding or mitigating an
environmental effect. The project incorporates identified standards and regulations in effect for the
protection of the environment.
LESS-THAN-SIGNIFICANT IMPACT
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City of San Luis Obispo
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12 Mineral Resources
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Result in the loss of availability of a
known mineral resource that would be of
value to the region and the residents of
the state? □ □ □ ■
b. Result in the loss of availability of a
locally important mineral resource
recovery site delineated on a local
general plan, specific plan, or other land
use plan? □ □ □ ■
Environmental Setting
Pursuant to Policy 6.5.1 of the Conservation and Open Space Element of the City’s General Plan,
mineral extraction is prohibited within City limits (City of San Luis Obispo 2014b).
Impact Analysis
a. Would the project result in the loss of availability of a known mineral resource that would be of
value to the region and the residents of the state?
b. Would the project result in the loss of availability of a locally important mineral resource
recovery site delineated on a local general plan, specific plan, or other land use plan?
The well sites are located on land classified as a Mineral Resources Zone-3, a classification where
mineral resources of unknown significance exist (DOC 1989). The well sites are within an existing
urbanized area of the City and the Conservation and Open Space Element of the City’s General Plan
prohibits mineral extraction. As such, the project would not result in the loss of availability of a
known mineral resource or locally important mineral resource recovery site delineated on a local
general plan, specific plan, or other land use plan. Therefore, no impacts would occur.
NO IMPACT
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Mineral Resources
Final Initial Study – Mitigated Negative Declaration 71
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13 Noise
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project result in:
a. Generation of a substantial temporary or
permanent increase in ambient noise
levels in the vicinity of the project in
excess of standards established in the
local general plan or noise ordinance, or
applicable standards of other agencies? □ ■ □ □
b. Generation of excessive groundborne
vibration or groundborne noise levels? □ □ ■ □
c. For a project located within the vicinity of
a private airstrip or an airport land use
plan or, where such a plan has not been
adopted, within two miles of a public
airport or public use airport, would the
project expose people residing or
working in the project area to excessive
noise levels? □ □ □ ■
Environmental Setting
Sound is a vibratory disturbance created by a moving or vibrating source, which is capable of being
detected by the hearing organs. Noise is defined as sound that is loud, unpleasant, unexpected, or
undesired and may therefore be classified as a more specific group of sounds. The effects of noise
on people can include general annoyance, interference with speech communication, sleep
disturbance, and, in the extreme, hearing impairment. Noise levels are commonly measured in
decibels (dB) using the A-weighted sound pressure level (dBA). The A-weighting scale is an
adjustment to the actual sound pressure levels so that they are consistent with the human hearing
response. Groundborne vibration of concern in environmental analysis consists of the oscillatory
waves that move from a source through the ground to adjacent buildings or structures and vibration
energy may propagate through the buildings or structures. The primary concern from vibration is
that it may cause structural damage.
The City Municipal Code Chapter 9.12 - Noise Control, mandates that operating tools or equipment
used for construction activities between weekday hours of 7:00 p.m. and 7:00 a.m. or any time on
Sundays or holidays is strictly prohibited, except for emergency works of public service utilities or by
exception issued by the City Community Development Department. The Municipal Code also states
that construction activities shall be conducted in such a manner, where technically and economically
feasible, that the maximum noise levels at affected properties shall not exceed 75 dBA at single-
family residences, 80 dBA at multi-family residences, and 85 dBA at mixed residential/commercial
uses. The Municipal Code prohibits operating any device that creates ground vibration above the
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Environmental Checklist
Noise
Final Initial Study – Mitigated Negative Declaration 73
vibration perception threshold of an individual at or beyond 150 feet from the source on a public
space or right-of-way.
Noise exposure for various types of land uses reflect the varying noise sensitivities associated with
those uses. Sensitive receptors typically include residences, schools, healthcare facilities, and other
live-in housing facilities such as prisons or dormitories. The closest sensitive receptors to the project
site include single-family residences located approximately 15 feet east of MW-10, a single-family
residence located approximately 45 feet north of MW-06, a single-family residence located
approximately 50 feet east of MW-01 and mobile homes located approximately 65 feet north of
MW-03.
Regarding human perception, vibration levels would begin to be perceptible at levels of 0.04 inches
per second peak particle velocity (in/sec ppv) for continuous events and 0.25 in/sec ppv for
transient events (Caltrans 2020).
Impact Analysis
a. Would the project result in generation of a substantial temporary or permanent increase in
ambient noise levels in the vicinity of the project in excess of standards established in the local
general plan or noise ordinance, or applicable standards of other agencies?
Noise from construction equipment, site disturbance, and other project activities may temporarily
and intermittently dominate the noise environment in the immediate vicinity of the wells. As stated
above, the closest sensitive receptors to the project site include single-family residences located
approximately 15 feet east of MW-10, a single-family residence located approximately 45 feet north
of MW-06, a single-family residence located approximately 50 feet east of MW-01 and mobile
homes located approximately 65 feet north of MW-03. The nearest sensitive receptors to the
treatment well site are single-family residences located approximately 245 feet east of the
treatment well site. The portion of the Bob Jones Trail within the treatment well site is a
recreational use which is not considered a sensitive receptor. Table 6 shows typical noise levels
produced by common construction equipment anticipated to be used during construction of the
proposed monitoring wells and treatment well.
Table 6 Typical Noise Levels for Construction Equipment
Equipment Typical Noise Level 50 Feet from Source, dBA
Backhoe 80
Concrete Pump 82
Crane, Mobile 83
Rock Drill 95
Source: Federal Transit Administration 2018
At 245 feet, use of the construction equipment shown in Table 6 would result in a maximum noise
level of approximately 71 dBA which would not exceed the 75 dBA threshold established in the City
Municipal Code (Appendix C). Therefore, construction at the treatment well site would have a less
than significant impact related to construction noise.
Construction activities would occur at each monitoring well for approximately four days; therefore,
the time which sensitive noise receptors near monitoring well locations would be exposed to
construction noise would be short-term. However, use of this construction equipment could exceed
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74
75 dBA as far as 150 feet from each monitoring well site (Appendix C). Therefore, sensitive noise
receptors near monitoring well locations (primarily residential properties within 150 feet of MW-01,
MW-02, MW-03, MW-06, and MW-10) would be exposed to intermittent and temporary
construction noise levels that exceed Municipal Code standards for construction near single-family
residential properties. As such, there would be a potentially significant impact to residential
properties surrounding monitoring well locations from short-term construction noise.
The proposed project would not include any operational components that create substantial noise
or otherwise introduce any long-term operational noise sources in the city. Therefore, operation of
the proposed project would have a less than significant impact related to excessive noise.
Mitigation Measures
N-1 Noise Reducing Best Management Practices
During monitoring well installation at MW-01, MW-02, MW-03, MW-06, and MW-10, the following
construction noise best management practices shall be adhered to:
Stationary construction equipment that generates noise that exceeds 60 dBA shall be shielded
with the most modern noise control devices (i.e. mufflers, lagging, and/or motor enclosures).
Impact tools (e.g., drills) used for project construction shall be hydraulically or electrically
powered wherever possible to avoid noise associated with compressed-air exhaust from
pneumatically powered tools.
Where use of pneumatic tools is unavoidable, an exhaust muffler on the compressed-air
exhaust shall be used.
All construction equipment shall have the manufacturers’ recommended noise abatement
methods installed, such as mufflers, engine enclosures, and engine vibration insulators, intact
and operational.
All construction equipment shall undergo inspection at periodic intervals to ensure proper
maintenance and presence of noise control devices (e.g., mufflers, shrouding, etc.).
At least 21 days prior to the start of construction, notify off-site businesses and residents within
150 feet of construction of planned construction activities. The notification shall provide brief
description of the project, activities that would occur, hours of construction, the duration of
construction, and a phone number to the City Community Development Department for the
public to direct noise-related complaints.
N-2 City Approval and Personnel Briefing
Construction plans shall note construction hours, truck routes, and all construction noise best
management practices, and shall be reviewed and approved by the City Utilities Department prior
to advertisement of the construction request for bids. All construction workers shall be briefed at a
preconstruction meeting on construction hour limitations and how, why, and where best
management practices are to be implemented.
Significance After Mitigation
Mitigation Measures N-1 and N-2 require implementation of standards noise best management
practices, such as the use of electric or hydraulically powered impact tools, and requirements for
signs and briefing of construction employees regarding all noise control measures to be
implemented throughout the construction phase. The Municipal Code states, where technically and
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Environmental Checklist
Noise
Final Initial Study – Mitigated Negative Declaration 75
economically feasible, construction activities shall be conducted in such a manner that the
maximum noise levels at affected properties will not exceed listed thresholds. Mitigation
Measures N-1 and N-2 serve as mitigation that would lower temporary and intermittent noise levels
to the extent technically and economically feasible. Therefore, following implementation of
Mitigation Measures N-1 and N-2, the proposed project would be consistent with the Municipal
Code, and this impact would be reduced to a less than significant level.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
b. Would the project result in generation of excessive groundborne vibration or groundborne noise
levels?
Use of a rotary sonic drill or hollow-stem auger for drilling would generate temporary and
intermittent groundborne noise or groundborne vibration during construction. These construction
activities would be periodic and limited in duration. As stated above, the closest sensitive receptors
to the project site include single-family residences located near monitoring well sites, including a
single-family residence located approximately 15 feet east of MW-10, a single-family residence
located approximately 45 feet north of MW-06, a single-family residence located approximately 50
feet east of MW-01 and mobile homes located approximately 65 feet north of MW-03.
Vibration levels associated with monitoring well drilling would begin to be perceptible at levels of
0.04 in/sec ppv for continuous events and 0.25 in/sec ppv for transient events. Given the short
duration and infrequent nature of drilling at the monitoring wells occurring during daytime hours,
the 0.25 in/sec ppv threshold for transient events is utilized for this analysis. At 15 feet, drilling
could result in a vibration level of approximately 0.19 in/sec ppv which would not exceed the exceed
the 0.25 in/sec ppv for transient events (Appendix C). Given that the 15 feet represents the closest
distance between a proposed well (MW-10) and sensitive receptor, monitoring well drilling would
not generate substantial groundborne vibration or groundborne noise exceeding applicable human
annoyance thresholds.
During operation, the proposed project would not include any components which would generate
any significant groundborne vibration or noise. Therefore, this impact would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
c. For a project located within the vicinity of a private airstrip or an airport land use plan or,
where such a plan has not been adopted, within two miles of a public airport or public use
airport, would the project expose people residing or working in the project area to excessive
noise levels?
All wells except for MW-01 and MW-02 would be located within two miles of San Luis Obispo
County Regional Airport. However, according to the Airport Land Use Plan for the airport, the well
sties would be located outside of the noise contours of the San Luis Obispo County Regional Airport
(RS&H 2021). Therefore, the project would not expose construction workers to excessive airport
noise. Furthermore, the project does not include development of habitable or occupiable structures
and therefore would not expose any occupants to excessive airport noise. No impact would occur.
NO IMPACT
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14 Population and Housing
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Induce substantial unplanned population
growth in an area, either directly (e.g., by
proposing new homes and businesses) or
indirectly (e.g., through extension of
roads or other infrastructure)? □ □ □ ■
b. Displace substantial numbers of existing
people or housing, necessitating the
construction of replacement housing
elsewhere? □ □ □ ■
Environmental Setting
As of January 1, 2024, San Luis Obispo County’s population was 278,469 with 262,597 households,
and the City’s population was 48,684 persons, with 47,293 households (California Department of
Finance [DOF] 2024).
Impact Analysis
a. Would the project induce substantial unplanned population growth in an area, either directly
(for example, by proposing new homes and businesses) or indirectly (for example, through
extension of roads or other infrastructure)?
b. Would the project displace substantial numbers of existing people or housing, necessitating the
construction of replacement housing elsewhere?
The project would not require the removal of housing and therefore would not displace people or
housing. The project would not result in the construction of habitable structures or
commercial/industrial uses and would not induce population growth. The project would utilize a
minor number of temporary construction personnel over the course of the approximate 120
working day period for TW-4 and 50 working days for monitoring wells. Construction equipment
would be staged within individual work zones on City property or within City easement, which
would not interfere with surrounding infrastructure. Once completed, the project would not involve
ongoing operational uses that would result in new employment opportunities. The project would
not induce substantial unplanned population growth in an area, either directly or indirectly, or
require the displacement of existing people or housing. No impact would occur.
NO IMPACT
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Population and Housing
Final Initial Study – Mitigated Negative Declaration 77
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15 Public Services
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
a. Would the project result in substantial
adverse physical impacts associated with
the provision of new or physically altered
governmental facilities, or the need for
new or physically altered governmental
facilities, the construction of which could
cause significant environmental impacts,
in order to maintain acceptable service
ratios, response times or other
performance objectives for any of the
public services:
1 Fire protection? □ □ ■ □
2 Police protection? □ □ ■ □
3 Schools? □ □ □ ■
4 Parks? □ □ □ ■
5 Other public facilities? □ □ □ ■
Environmental Setting
The San Luis Obispo Fire Department (SLOFD) provides fire protection services for the City. The fire
stations nearest to the well sites are Station 1, located at 2160 Santa Barbara Avenue,
approximately 0.75-mile northeast of MW-1, and Station 4, located at 1395 Madonna Road, 2,000
feet northwest of MW-6. In 2023, SLOFD maintained an average travel time of five minutes and 53
seconds, with a total response time of eight minutes and 41 seconds (SLOFD 2023).
The San Luis Obispo Police Department (SLOPD) provides public safety services for the City. SLOPD’s
Operation Bureau provides 24-hours emergency and non-emergency response, traffic enforcement,
and neighborhood outreach (SLOPD 2024). The SLOPD operates out of one police station located at
1042 Walnut Street.
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Environmental Checklist
Public Services
Final Initial Study – Mitigated Negative Declaration 79
Impact Analysis
a. Would the project result in substantial adverse physical impacts associated with the provision
of new or physically altered governmental facilities, or the need for new or physically altered
governmental facilities, the construction of which could cause significant environmental
impacts, in order to maintain acceptable service ratios, response times or other performance
objectives for any of the public services:
1 Fire protection?
2 Police protection?
The project would not induce population growth, either directly or indirectly, or include any actions
that would have the potential to increase demand for fire protection or police protection services
such that new or physically altered fire or police stations would be warranted. If necessary,
supporting fire or police protective services during temporary construction activities would be
provided by the City’s police or fire departments. The project would not result in substantial
physical impacts associated with the provision of new or physically altered governmental facilities,
the construction of which could cause significant environmental impacts, in order to maintain
acceptable service ratios, response times or other performance objectives for fire protection
services or police protection services. No significant impacts to public services would occur.
LESS-THAN-SIGNIFICANT IMPACT
a. Would the project result in substantial adverse physical impacts associated with the provision
of new or physically altered governmental facilities, or the need for new or physically altered
governmental facilities, the construction of which could cause significant environmental
impacts, in order to maintain acceptable service ratios, response times or other performance
objectives for any of the public services:
3 Schools?
4 Parks?
5 Other public facilities?
The project would not induce population growth, either directly or indirectly, or include any actions
that would have the potential to increase demand for schools, libraries or other public services such
that new or physically altered public facilities would be warranted. Project activities would be
temporary and contained within individual work zones on City property or within City easement or
right-of-way, precluding the possibility to interfere with the existing use of parks or recreational
facilities. The project would not result in substantial physical impacts associated with the provision
of new or physically altered governmental facilities, the construction of which could cause
significant environmental impacts, in order to maintain acceptable service ratios or other
performance objectives for schools, parks, or other public facilities. No impact would occur.
NO IMPACT
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16 Recreation
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
a. Would the project increase the use of
existing neighborhood and regional parks
or other recreational facilities such that
substantial physical deterioration of the
facility would occur or be accelerated? □ □ □ ■
b. Does the project include recreational
facilities or require the construction or
expansion of recreational facilities which
might have an adverse physical effect on
the environment? □ □ □ ■
Environmental Setting
The Park and Recreation Blueprint for the Future identifies 28 City parks and 15 recreational
facilities in the City, including a golf course, sports complex, stadium, swim center, community
center, skate park, senior center, and community gardens. Additionally, the City owns and manages
13 open spaces and recreational trails that cover approximately 4,050 acres (City of San Luis Obispo
2021).
Impact Analysis
a. Would the project increase the use of existing neighborhood and regional parks or other
recreational facilities such that substantial physical deterioration of the facility would occur or
be accelerated?
b. Does the project include recreational facilities or require the construction or expansion of
recreational facilities which might have an adverse physical effect on the environment?
The project would not induce population growth, either directly or indirectly, which would have the
potential to increase the demand for parks or other recreational facilities. Temporary construction
activities would be staged within individual work zones on City property or within City easement,
precluding the possibility to interfere with or prohibit the use of existing neighborhood or regional
parks or other recreational facilities such that other parks or recreational facilities would be utilized
more frequently, and substantial physical deterioration of the facility would occur or be accelerated.
The project does not include construction of recreational facilities and would not require the
construction or expansion of recreational facilities which might have an adverse physical effect on
the environment. Therefore, no impacts to recreation would occur.
NO IMPACT
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Recreation
Final Initial Study – Mitigated Negative Declaration 81
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17 Transportation
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Conflict with a program, plan, ordinance
or policy addressing the circulation
system, including transit, roadway,
bicycle and pedestrian facilities? □ □ ■ □
b. Conflict or be inconsistent with CEQA
Guidelines section 15064.3, subdivision
(b)? □ □ ■ □
c. Substantially increase hazards due to a
geometric design feature (e.g., sharp
curves or dangerous intersections) or
incompatible use (e.g., farm equipment)? □ □ ■ □
d. Result in inadequate emergency access? □ □ ■ □
Environmental Setting
Regional access to the project site is available via U.S. 101. Monitoring wells are located throughout
the City of San Luis Obispo and are accessed via local roads. Local access to the treatment well site is
provided via Prado Road, Los Osos Valley Road, and Calle Joaquin. Bicycle facilities on these streets
include buffered lanes and protected bike lanes (City of San Luis Obispo 2024a). In addition, the
treatment well site includes a portion of the Bob Jones Trail which is a multi-use path available for
cyclists and pedestrians.
Impact Analysis
a. Would the project conflict with a program, plan, ordinance or policy addressing the circulation
system, including transit, roadway, bicycle and pedestrian facilities?
Trips associated with project activities would be limited to worker trips to and from the project site,
delivery trips for heavy equipment and construction tools, and trips to dispose of soil and other
construction debris. Construction-related vehicle trips would be temporary and would cease once
construction is complete. Construction contractors would be required to comply with the temporary
traffic control provisions set forth in the City’s Standard Specifications and Engineering Standards
(City of San Luis Obispo 2020b). This document provides guidelines for traffic control during
construction, including maintaining traffic, specifications for flagging, pavement delineation, among
other topics. In addition, a Traffic Control Plan, compliant with the provisions set forth in the
Caltrans Manual on Uniform Traffic Control Devices would be required to be approved by the City
Engineer or their designee prior to the start of construction activities. All traffic coordination on City
Streets and within the Bob Jones Bikepath undertaken by construction contractors would require
the City Engineer’s approval no fewer than three days prior to implementation of traffic
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Environmental Checklist
Transportation
Final Initial Study – Mitigated Negative Declaration 83
coordination activities (City of San Luis Obispo 2020b). Compliance with these existing standards
and measures would ensure that project construction would not conflict with a program, plan,
ordinance or policy addressing the circulation system.
Operation of the project would result in minimal vehicle trips for occasional monitoring activities,
and these trips would not result in vehicle traffic which could conflict with a program, plan,
ordinance or policy addressing the circulation system. Therefore, this impact would be less than
significant.
LESS-THAN-SIGNIFICANT IMPACT
b. Would the project conflict or be inconsistent with CEQA Guidelines section 15064.3,
subdivision (b)?
CEQA Guidelines Section 15064.3 describes specific considerations for evaluating a project’s
transportation impacts. Specifically, the guidelines state VMT exceeding an applicable threshold of
significance may indicate a significant impact. Pursuant to CEQA Guidelines Section 15064.3(b)(3), a
lead agency may include a qualitative analysis of project-related traffic. The City has adopted VMT
thresholds consistent with the thresholds and methodologies contained in the California Governor’s
Office of Land Use and Climate Innovation’s (formerly the Governor’s Office of Planning and
Research) Technical Advisory on Evaluating Transportation Impacts in CEQA (City of San Luis Obispo
2020c). As described therein, a project that is anticipated to generate less than 110 vehicle trips per
day may be assumed to cause a less than significant impact.
Construction of the proposed project would result in short-term, temporary vehicle trips to and
from the project site during the construction period. These temporary vehicle trips would not result
in long-term changes to VMT within San Luis Obispo; therefore, project construction VMT would not
conflict or be inconsistent with CEQA Guidelines Section 15064.3(b).
During operation, minimal maintenance trips would be required to monitor the wells and maintain
the extraction and treatment system; however, these trips would not result in an exceedance of 110
daily vehicle trips, and the project would not generate growth or create an increase in traffic such
that substantial increases in VMT could occur. Therefore, the project would not conflict or be
inconsistent with CEQA Guidelines Section 15064.3(b), and this impact would be less than
significant.
LESS-THAN-SIGNIFICANT IMPACT
c. Would the project substantially increase hazards due to a geometric design feature (e.g., sharp
curves or dangerous intersections) or incompatible use (e.g., farm equipment)?
The proposed project would not alter or affect the city’s existing street network. Construction of
MW-01, MW-05, MW-07, MW-08, MW-10, and MW-12 may temporarily result in partial road
closures; however, construction contractors would be required to comply with temporary traffic
control provisions set forth in the City’s Standard Specifications and Engineering Standards,
including implementation of a traffic control plan to reduce temporary traffic hazards during
construction (City of San Luis Obispo 2020b). At the completion of construction activity, equipment
would be removed, and the monitoring wells would be located underground. The project site would
not have any new geometric design features or incompatible uses that would increase hazards for
vehicular and pedestrian traffic. Therefore, the proposed project would not substantially increase
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84
hazards due to a geometric design feature or incompatible uses. This impact would be less than
significant.
LESS-THAN-SIGNIFICANT IMPACT
d. Would the project result in inadequate emergency access?
Traffic impacts during project construction would be primarily associated with minor roadway and
multi-use pathway delays and temporary partial lane closures. However, any minor delays during
project construction would be temporary in nature and would not result in long-term inadequate
emergency access. To minimize potential impacts to emergency access during construction, the
project would be required to comply with the City’s Standard Specifications and Engineering
Standards and implement a traffic control plan that adheres to City standards for emergency access,
including prohibiting personal vehicles of construction workers from parking on the traveled way of
the construction zone and approval from the City’s Engineer or their designee for any traffic
restrictions (City of San Luis Obispo 2020b). Operation of the project would not impair emergency
access as wells would be located underground, and minimal operational vehicle trips would be
required. Therefore, the proposed project would have a less than significant impact related to
emergency access.
LESS-THAN-SIGNIFICANT IMPACT
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Transportation
Final Initial Study – Mitigated Negative Declaration 85
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18 Tribal Cultural Resources
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project cause a substantial adverse
change in the significance of a tribal cultural
resource, defined in a Public Resources Code
Section 21074 as either a site, feature, place,
or cultural landscape that is geographically
defined in terms of the size and scope of the
landscape, sacred place, or object with
cultural value to a California Native American
tribe, and that is:
a. Listed or eligible for listing in the
California Register of Historical
Resources, or in a local register of
historical resources as defined in Public
Resources Code Section 5020.1(k)? □ ■ □ □
b. A resource determined by the lead
agency, in its discretion and supported by
substantial evidence, to be significant
pursuant to criteria set forth in
subdivision (c) of Public Resources Code
Section 5024.1? In applying the criteria
set forth in subdivision (c) of Public
Resources Code Section 5024.1, the lead
agency shall consider the significance of
the resource to a California Native
American tribe. □ ■ □ □
Environmental Setting
California Assembly Bill 52 of 2014 (AB 52) expanded CEQA by defining a new resource category,
“tribal cultural resources.” AB 52 establishes that “a project with an effect that may cause a
substantial adverse change in the significance of a tribal cultural resource is a project that may have
a significant effect on the environment” (PRC Section 21084.2). It further states that the lead agency
shall establish measures to avoid impacts that would alter the significant characteristics of a tribal
cultural resource, when feasible (PRC Section 21084.3).
PRC Section 21074 (a)(1)(A-B) defines tribal cultural resources as “sites, features, places, cultural
landscapes, sacred places, and objects with cultural value to a California Native American tribe” and
are:
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Environmental Checklist
Tribal Cultural Resources
Final Initial Study – Mitigated Negative Declaration 87
1. Listed or eligible for listing in the CRHR, or in a local register of historical resources as defined in
PRC Section 5020.1(k), or
2. A resource determined by the lead agency, in its discretion and supported by substantial
evidence, to be significant pursuant to criteria set forth in PRC Section 5024.1(c). In applying
these criteria, the lead agency shall consider the significance of the resource to a California
Native American tribe.
The City sent notification letters to listed tribal contacts in the region on July 25, 2024, which
included the Santa Ynez Band of Mission Indians, the Barbareno/Ventureno Band of Mission Indians,
the Salinan Tribe of Monterey and San Luis Obispo County, the Tule River Indian TribeYak Tityu Tityu
– Northern Chumash Tribe, the Northern Chumash Tribal Council, the Torres Martinez Desert
Cahuilla Indians, the Chumash Council of Bakersfield, and the Coastal Band of the Chumash Nation.
Native American Tribes were notified on July 25, 2024 about the project consistent with City and
State regulations including, but not limited to, Assembly Bill 52. During the request for consultation
window, two responses were received. The Salinan Tribe of Monterey responded on August 30,
2024 requesting notification in the event of a cultural resource discovery during construction. It is
standard City policy to notify local Native American tribes, including and not limited to the Salinan
Tribe of Monterey, in the event of a cultural resource discovery during construction; in addition,
specific language has been added to CUL-3 requiring notification of Native American tribal
representatives. The Santa Ynez Band of Chumash Indians contacted the City on August 5, 2024
requesting a consultation meeting to discuss the project. The City consulted with the Tribe on
September 17, 2024 and shared information regarding the project, the results of the cultural
resources survey, and proposed mitigation measures. The Tribe informed the City that they are in
agreement with the mitigation measures laid out in the public review Draft IS-MND for a workers
environmental awareness program training, archaeological monitoring, and protocol in the event of
unanticipated discoveries. Pursuant to PRC §21080.3.1 (b) the request for consultation window
closed on August 26, 2024. No other tribal agencies responded to the consultation request.
In addition, the IS-MND was provided to Native American Tribes during the public review period.
The City received additional correspondence from the Santa Ynez Band of Chumash Indians,
consisting of a request for minor modifications to the language of mitigation measure CUL-1
(Workers Environmental Awareness Program Training). The Final IS-MND incorporates the
requested amendment into CUL-1. The City also received a request for maps and photos of the
project area and the archaeological report including record-search information from the Northern
Chumash Tribal Council; this information was provided by City staff and no further comments were
received.
Impact Analysis
a. Would the project cause a substantial adverse change in the significance of a tribal cultural
resource as defined in Public Resources Code Section 21074 that is listed or eligible for listing in
the California Register of Historical Resources, or in a local register of historical resources as
defined in Public Resources Code Section 5020.1(k)?
b. Would the project cause a substantial adverse change in the significance of a tribal cultural
resource as defined in Public Resources Code 21074 that is a resource determined by the lead
agency, in its discretion and supported by substantial evidence, to be significant pursuant to
criteria set forth in subdivision (c) of Public Resources Code Section 5024.1?
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During preparation of the Cultural Resources Assessment, Rincon contacted the NAHC on
December 17, 2021, requesting an SLF search for traditional cultural resources. The NAHC
responded on March 11, 2022, indicating the results of the SLF search was positive, meaning
traditional cultural resources are present within the SLF search area. The NAHC provided a
consultation list of 14 Native American groups within traditional lands or cultural places located
within the SLF search area.
SLF searches are conducted by using USGS quadrangle maps, each of which covers an approximately
50- to 70-square-mile area, and the NAHC does not provide the specific location of tribal heritage
resources. Consequently, a positive SLF search does not explicitly indicate the presence of tribal
cultural resources on the project site. However, based on the positive results of the SLF search, the
project site could have the potential to contain tribal cultural resources that could be eligible for
listing in the CRHR or local register, or considered to be a tribal cultural resource under CEQA. As
discussed in Section 5, Cultural Resources, the potential to encounter archaeological resources
during ground-disturbing activities exists. If encountered, previously undiscovered cultural
resources could potentially be considered eligible for listing in the CRHR or a local register or be
considered tribal cultural resources. As such, impacts to tribal cultural resources would be
potentially significant.
Mitigation Measures CR-1, CR-2, and CR-3 CUL-1, CUL-2, and CUL-3 would implement a worker’s
environmental awareness program, standard procedures for the unanticipated discovery of cultural
resources, require a Native American representative to participate in the worker’s environmental
awareness program and evaluation of unanticipated cultural resources discovered during
construction activities, and enforce procedures for Native American consultation in the event
human remains are discovered. Upon implementation of Mitigation Measures CR-1, CR-2, CUL-1 and
CUL-2 the project would not cause a substantial adverse change in the significance of a tribal
cultural resource.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
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Tribal Cultural Resources
Final Initial Study – Mitigated Negative Declaration 89
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19 Utilities and Service Systems
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Would the project:
a. Require or result in the relocation or
construction of new or expanded water,
wastewater treatment or storm water
drainage, electric power, natural gas, or
telecommunications facilities, the
construction or relocation of which could
cause significant environmental effects? □ □ ■ □
b. Have sufficient water supplies available
to serve the project and reasonably
foreseeable future development during
normal, dry and multiple dry years? □ □ ■ □
c. Result in a determination by the
wastewater treatment provider which
serves or may serve the project that it
has adequate capacity to serve the
project’s projected demand in addition to
the provider’s existing commitments? □ □ ■ □
d. Generate solid waste in excess of State or
local standards, or in excess of the
capacity of local infrastructure, or
otherwise impair the attainment of solid
waste reduction goals? □ □ ■ □
e. Comply with federal, state, and local
management and reduction statutes and
regulations related to solid waste? □ □ ■ □
Environmental Setting
The City’s Utilities Department provides water and wastewater services to the City. Wastewater
generated within the City, California Polytechnic State University, and the County airport is treated
at the Water Resource Recovery Facility (WRRF). The WRRF treats approximately 4.5 million gallons
of wastewater daily (City of San Luis Obispo 2024c). The City’s Utilities Department is also
responsible for administering an agreement with the San Luis Garbage Company for waste
collection services. Most solid waste collected in the City is disposed of at the Cold Canyon Landfill
(City of San Luis Obispo 2014a). Cold Canyon Landfill has a maximum permitted capacity of 1,650
tons per day (California Department of Resources, Recycling, and Recovery [CalRecycle] 2020). As of
2020, the landfill’s estimated remaining capacity was 13,000,000 cubic yards with an estimated
closure date of December 2040 (CalRecycle 2020). Electricity services in the City are provided by
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Utilities and Service Systems
Final Initial Study – Mitigated Negative Declaration 91
Pacific Gas & Electric Company and natural gas services are provided by the Southern California Gas
Company.
Impact Analysis
a. Would the project require or result in the relocation or construction of new or expanded water,
wastewater treatment or storm water drainage, electric power, natural gas, or
telecommunications facilities, the construction or relocation of which could cause significant
environmental effects?
b. Would the project have sufficient water supplies available to serve the project and reasonably
foreseeable future development during normal, dry and multiple dry years?
c. Would the project result in a determination by the wastewater treatment provider which serves
or may serve the project that it has adequate capacity to serve the project’s projected demand
in addition to the provider’s existing commitments?
As described under Section 3, Air Quality, construction activities would require minimum amounts
of water for dust suppression. Adequate water supplies would be available to meet the needs of the
project for dust suppression purposes. In accordance with Municipal Code Section 13.07.070(c),
potable City water would not be used for major construction activities, such as grading and dust
control, and would not be used to wash down sidewalks, driveways, or parking areas except to
alleviate immediate fire or sanitation hazards. Consequently, the project would not use the City’s
drinking water for dust suppression. No buildings or structures would be constructed that would
result in new long-term water demand. Minimal wastewater would be generated by construction
worker personnel during temporary construction activities (approximately 120 working days for the
TW-4 and 50 working days for the monitoring wells, including testing) which would be served by on-
site portable restroom facilities. The City’s WRRF and collection system has sufficient capacity to
accept the wastewater generated by the treatment process. Groundwater extraction would occur in
compliance with SGMA and the adopted GSP to ensure to adverse impacts occur to the
groundwater basin or flows within San Luis Obispo Creek.
Therefore, the project would have sufficient water supplies available, would not require or result in
relocation or construction of new or expanded water or stormwater facilities, and would not exceed
wastewater treatment demand beyond existing conditions.
As discussed in Section 6, Energy, the project would require minimal, temporary energy use
throughout construction, and construction equipment used would be typical of similar-sized
construction projects in the region. Project operation would not increase the demand for additional
electric power or natural gas as compared to existing conditions. Therefore, the project would not
require or result in additional electric power or natural gas facilities. Similarly, the project would not
require the need for additional telecommunications facilities.
Overall, the project would not require relocation or construction of new or expanded utilities
facilities, increase water demand, or result in inadequate wastewater treatment capacity. These
impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
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d. Would the project generate solid waste in excess of State or local standards, or in excess of the
capacity of local infrastructure, or otherwise impair the attainment of solid waste reduction
goals?
e. Would the project comply with federal, state, and local management and reduction statutes
and regulations related to solid waste?
Project construction activities would generate construction waste; wastes derived from well
installation and well development activities would include soil cuttings, decontamination water, and
development water. The construction contractor would be required to submit samples of drilling
spoils for analytical testing required for waste profiling. Based on the results of the analytical
testing, soil cuttings and water would be containerized in 55-gallon drums, temporarily stored on-
site or at an appropriate location, and profiled for disposal; derived wastes would be transported
off-site and disposed of at an appropriate disposal facility.
For other temporary solid waste applicable to landfill (i.e. trash, green, sand, and/or non-recyclable
PCC), Cold Canyon Landfill has sufficient permitted capacity to accommodate the project’s
temporary solid waste disposal needs associated with construction activities. Pursuant to Assembly
Bill 939 and Municipal Code Chapter 8.04, recoverable materials generated during construction
would be separated and recycled to minimize construction and waste exportation from the site,
resulting in limited demand on the landfills within the County. Operation of the project would not
generate solid waste. Therefore, the project would not generate solid waste in excess of State or
local standards, or in the excess of capacity of local infrastructure, and the project would comply
with federal, state, and local management reduction statues and regulations related to solid waste.
These impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
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20 Wildfire
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
If located in or near state responsibility areas
or lands classified as very high fire hazard
severity zones, would the project:
a. Substantially impair an adopted
emergency response plan or emergency
evacuation plan? □ □ ■ □
b. Due to slope, prevailing winds, and other
factors, exacerbate wildfire risks and
thereby expose project occupants to
pollutant concentrations from a wildfire
or the uncontrolled spread of a wildfire? □ □ ■ □
c. Require the installation or maintenance
of associated infrastructure (such as
roads, fuel breaks, emergency water
sources, power lines or other utilities)
that may exacerbate fire risk or that may
result in temporary or ongoing impacts
to the environment? □ □ ■ □
d. Expose people or structures to significant
risks, including downslopes or
downstream flooding or landslides, as a
result of runoff, post-fire slope instability,
or drainage changes? □ □ ■ □
Environmental Setting
The central coast of California is prone to wildfire due to a warm, dry climate and expansive
coverage of ignitable vegetation. However, the project site is not within a State Responsibility Area
or a Very High Fire Hazard Severity Zone as defined by CAL FIRE (CALFIRE 2024). The closest Fire
Hazard Severity Zone to the treatment well site is approximately one mile west, extending from
foothills of Mine Hill.
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Wildfire
Final Initial Study – Mitigated Negative Declaration 95
Impact Analysis
a. If located in or near state responsibility areas or lands classified as very high fire hazard severity
zones, would the project substantially impair an adopted emergency response plan or
emergency evacuation plan?
b. If located in or near state responsibility areas or lands classified as very high fire hazard severity
zones, would the project, due to slope, prevailing winds, and other factors, exacerbate wildfire
risks and thereby expose project occupants to pollutant concentrations from a wildfire or the
uncontrolled spread of a wildfire?
c. If located in or near state responsibility areas or lands classified as very high fire hazard severity
zones, would the project require the installation or maintenance of associated infrastructure
(such as roads, fuel breaks, emergency water sources, power lines or other utilities) that may
exacerbate fire risk or that may result in temporary or ongoing impacts to the environment?
d. If located in or near state responsibility areas or lands classified as very high fire hazard severity
zones, would the project expose people or structures to significant risks, including downslopes
or downstream flooding or landslides, as a result of runoff, post-fire slope instability, or
drainage changes?
The project site is not within a State Responsibility Area or a Very High Fire Hazard Severity Zone
(CAL FIRE 2024). The project would involve the movement of construction equipment, hauling of
construction equipment, and transportation of construction personnel which could temporarily
increase traffic on roadways when accessing the well locations, which could possibly delay
emergency vehicles. However, any minor delays during project construction would be temporary in
nature and would not impair an adopted emergency response plan or emergency evacuation plan.
The project would be required to comply with the City’s Standard Specifications and Engineering
Standards and implement a traffic control plan that adheres to City standards for emergency access.
Therefore, the project would not substantially impair an adopted emergency response plan or
emergency evacuation plan.
Heavy duty equipment used during construction that may produce sparks that could ignite
vegetation would be limited through regulatory compliance. California Public Resources Code
Section 4442 mandates the use of spark arrestors, which prevent the emission of flammable debris
from exhaust on earth-moving and portable construction equipment with internal combustion
engines that are operating on any forest-covered, brush-covered, or grass-covered land. PRC Section
4428 requires construction contractors to maintain fire suppression equipment during the highest
fire danger period (April 1 to December 1) when operating on or near any forest-covered, brush-
covered, or grass-covered land. These regulations would minimize the risk of fire resulting from
project construction activities. No roads, fuel breaks, emergency water sources, or power lines
would be installed. In addition, the project would not result in additional housing and would not
accommodate occupants. Thus, the project would not expose persons to pollutant concentrations
from a wildfire, exacerbate fire risk due to installation or maintenance of associated infrastructure,
or expose people or structures to significant risks as a result of runoff, post-fire slope instability, or
drainage changes. These impacts would be less than significant.
LESS-THAN-SIGNIFICANT IMPACT
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21 Mandatory Findings of Significance
Potentially
Significant
Impact
Less than
Significant
with
Mitigation
Incorporated
Less-than -
Significant
Impact No Impact
Does the project:
a. Have the potential to substantially
degrade the quality of the environment,
substantially reduce the habitat of a fish
or wildlife species, cause a fish or wildlife
population to drop below self-sustaining
levels, threaten to eliminate a plant or
animal community, substantially reduce
the number or restrict the range of a rare
or endangered plant or animal or
eliminate important examples of the
major periods of California history or
prehistory? □ ■ □ □
b. Have impacts that are individually
limited, but cumulatively considerable?
(“Cumulatively considerable” means that
the incremental effects of a project are
considerable when viewed in connection
with the effects of past projects, the
effects of other current projects, and the
effects of probable future projects)? □ ■ □ □
c. Have environmental effects which will
cause substantial adverse effects on
human beings, either directly or
indirectly? □ ■ □ □
Impact Analysis
a. Does the project have the potential to substantially degrade the quality of the environment,
substantially reduce the habitat of a fish or wildlife species, cause a fish or wildlife population
to drop below self-sustaining levels, threaten to eliminate a plant or animal community,
substantially reduce the number or restrict the range of a rare or endangered plant or animal or
eliminate important examples of the major periods of California history or prehistory?
The project is limited to activities that would occur at the treatment well site and monitoring well
sites; therefore, the project would not impact the total mapped habitat areas of the special-status
plant and animal species with potential to occur at these sites. The project does not include large-
scale activities which would pose a substantial threat to special-status species or their mapped
habitats. Due to the local scale of the project, the project would not substantially reduce the habitat
of a fish or wildlife species cause a fish or wildlife population to drop below self-sustaining levels,
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Environmental Checklist
Mandatory Findings of Significance
Final Initial Study – Mitigated Negative Declaration 97
threaten to eliminate a plant or animal community, or substantially reduce the number or restrict
the range of a rare or endangered plant or animal. This impact would be less than significant.
The well sites do not contain important examples of the major periods of California history or
prehistory. Therefore, the project would not have a substantial effect on these resources. As
discussed in Section 5, Cultural Resources, Mitigation Measures CR-1, CR-2, CR-3, and CR-4 would
minimize potential effects on cultural and tribal cultural resources. Accordingly, the project would
not eliminate important examples of the major periods of California history or prehistory.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
b. Does the project have impacts that are individually limited, but cumulatively considerable?
(“Cumulatively considerable” means that the incremental effects of a project are considerable
when viewed in connection with the effects of past projects, the effects of other current
projects, and the effects of probable future projects)?
As described in Sections 1 through 20, with respect to all environmental issues, the project’s
potential impacts associated with project construction activities would be either less than significant
or reduced to a less than significant level with implementation of required mitigation. This is
because project construction would be temporary, and project operation would not result in
adverse effects on the environmental baseline conditions. Cumulatively considerable impacts could
occur if the construction of other projects occurs at the same time as the project and in the same
vicinity, such that the effects of similar impacts of multiple projects combine to expose a resource to
greater levels of impact than would occur under the project.
Certain resource areas (e.g., Geology and Soils, Hazards and Hazardous Materials) are by their
nature specific to a project location, such that impacts at one location do not add to impacts at
other locations.
Other resource areas inherently address cumulative impacts. As noted in Section 3, Air Quality, and
Section 8, Greenhouse Gas Emissions, the project would comply with SLOAPCD’s Clean Air Plan and
the City’s Climate Action Plan, along with other regulations that would reduce the project’s air
quality impacts and greenhouse gas emissions to less than significant levels. The Clean Air Plan
establishes thresholds, and the Climate Action Plan contains a consistency checklist, both of which
that are designed such that a project that demonstrates compliance with these items would not
have an individually or cumulatively significant impact. Consequently, the project would not
generate a cumulatively considerable impacts to air quality or greenhouse gas emissions.
Additionally, the project would have no impact on agriculture and forestry resources, land use,
mineral resources, population and housing, public services, or recreation, and therefore, would not
have the potential to contribute to cumulative impacts to these environmental issue areas. The
discussion of cumulative impacts is limited to the following issue areas:
Aesthetics. Projects within San Luis Obispo have the potential to result in cumulative changes to
the city’s visual environment by introducing development that blocks scenic views, is visually
inconsistent with its surroundings, or introduces substantial light and glare. However, these
projects would be subject to the City’s applicable regulations related to scenic quality, height
limitations, and minimum setback requirements established within the City’s General Plan and
Municipal Code. These projects would implement City lighting standards to shield lighting from
adjacent sites. With adherence to City regulations related to aesthetics, cumulative
development in the City of San Luis Obispo would have a less than significant impact related to
aesthetics.
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98
Biological Resources. Cumulative projects that may be developed within the city would be
subject to similar regulatory requirements as the project. These include, but are not limited to,
the federal Endangered Species Act, California Endangered Species Act, and Migratory Bird
Treaty Act. These regulations are designed to protect individual species and their habitats.
Cumulative projects would be required to abide by the provisions of these regulations and
subject to review from agencies including, but not limited to, CDFW and the United States Fish
and Wildlife Service, to ensure potential impacts to species or habitat are minimized. However,
existing regulatory requirements alone cannot guarantee species loss, habitat loss, or other
impact to biological resources due to cumulative development. The project has the potential to
impact special-status species and nesting birds during construction, but the project would
incorporate mitigation measures, including worker environmental awareness training, pre-
construction surveys, and biological monitoring and special status species relocation or
avoidance. With incorporation of these measures, the project would not contribute
considerably to cumulative impacts related to biological resources.
Cultural Resources. Projects within San Luis Obispo, particularly those in undeveloped areas,
may disturb archaeological resources during construction and other ground-disturbing activities.
Therefore, cumulative development has the potential to have a significant impact on cultural
resources. Project construction at the well sites could result in potential disturbance to
subsurface archaeological resources; however, implementation of Mitigation Measures CUL-1
through CUL-3, which require construction worker training on identifying archaeological
resources, presence of Native American Tribal representatives, monitoring during ground
disturbance activities, and procedures for the unanticipated discovery of archaeological
resources. With incorporation of these measures, the project would not contribute considerably
to cumulative impacts related to cultural resources.
Energy. Cumulative projects in the city would use energy during construction and operation in
the form of gasoline, diesel, natural gas, and electricity. Cumulative development would be
required to comply with existing State regulations such as California Code of Regulations Title 13
Sections 2449 and 2485, the California Green Building Standards Code, and California Energy
Code, which are implemented, in part, to ensure development does not result in the wasteful,
inefficient, or unnecessary consumption of energy resources. With adherence to these
regulatory requirements, cumulative impacts related to energy would be less than significant.
Hydrology and Water Quality. The geographic area used to assess cumulative impacts to
surface water is the San Luis Obispo Creek watershed. The geographic area used to assess
cumulative impacts to groundwater is the San Luis Obispo Valley Groundwater Basin. A
cumulative impact could occur if projects discharge pollutants to the San Luis Obispo Creek
watershed and violate water quality standards, or if these projects would result in substantially
decreased groundwater supplies. Cumulative projects would be required to comply with
federal, state, and City water quality requirements, such as the Construction Stormwater
General Permit and City Standard Specifications and Engineering Standards (erosion and
sedimentation control, and water quality standards). Cumulative impacts to hydrology and
surface water quality would be minimized with adherence to these regulations. Therefore,
cumulative impacts to surface water would be less than significant. Cumulative development
could result in increased water demand from the San Luis Obispo Valley Groundwater Basin.
However, the basin is managed through the San Luis Obispo Valley Basin Groundwater
Sustainability Plan which would ensure cumulative development in San Luis Obispo does not
increase groundwater extraction beyond sustainable levels. As a result, cumulative
development would not receive groundwater in conflict with the sustainable management
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Environmental Checklist
Mandatory Findings of Significance
Final Initial Study – Mitigated Negative Declaration 99
policies of the San Luis Obispo Valley Groundwater Basin. Cumulative impacts related to
sustainable groundwater management would be less than significant
Noise. Construction and operational noise and vibration are localized and rapidly attenuate.
Cumulative construction impacts could occur if cumulative development in San Luis Obispo is
located proximate to the treatment or monitoring wells such that overlapping construction
schedules or operational noise- or vibration-generating sources could result in increased noise
and vibration at the same sensitive receptors. The closest cumulative development to the
project site is expansion of the WRRF, currently under construction, located adjacent to the
treatment well stie to the northeast (City of San Luis Obispo 2024d). Due to the proximity to the
project site, there is potential that if construction of the project and the WRRF overlapped,
nearby sensitive receptors could potentially be exposed to substantial noise. Therefore,
cumulative impacts are potentially significant. At the treatment well site the project would not
exceed the City’s 75 dBA threshold for construction noise. Therefore, the project would not
contribute considerably to cumulative noise impacts.
Transportation. Cumulative development could result in a greater number of vehicle trips in San
Luis Obispo compared to existing conditions, increasing citywide VMT, which would be a
significant cumulative impact. The project would require temporary construction trips which
would not result in long-term changes to VMT in San Luis Obispo. Operation of the project
would require minimal maintenance trips which would not exceed 110 daily trips, and would
not result in substantial increases in citywide VMT. Therefore, the project would not contribute
considerably to cumulative transportation impacts.
Utilities and Service Systems. Cumulative development could result in increased water demand
in excess of existing supplies, wastewater generation and solid waste generation in excess of
existing facilities’ capacity, and increased electric and natural gas demand requiring substantial
infrastructure. As described in the City’s Urban Water Management Plan, the City anticipates
having adequate water to supply cumulative development through 2040 in normal, single dry
years, and multiple dry years (City of San Luis Obispo 2024e). Therefore, cumulative water
supply impacts would be less than significant. The WRRF treats approximately 4.5 million gallons
per day and has a capacity of 5.1 million gallons per day. However, expansion to the WRRF,
anticipated to be completed in late 2024, would increase treatment capacity to 5.4 million
gallons per day, which is planned to accommodate wastewater flows in the City under full
General Plan buildout. Therefore, cumulative wastewater impacts would be less than significant.
Cold Canyon Landfill has an estimated remaining capacity of 13,000,000 cubic yards with an
estimated closure date of December 2040. Therefore, adequate landfill capacity is available to
serve cumulative development and cumulative solid waste impacts would be less than
significant. Existing electric and natural gas infrastructure is present throughout San Luis Obispo,
and cumulative development is anticipated to only require minor connections to existing natural
gas and electric infrastructure. Therefore, cumulative impacts to electric and natural gas
infrastructure would be less than significant.
Wildfire. Cumulative development in San Luis Obispo could result in wildfire hazards that could
potentially expose residents and employees within San Luis Obispo to wildfire or pollutants
associated with wildfire smoke. Cumulative development would be required to adhere to
applicable regulations to minimize fire risk, including the California Fire Code, California Public
Resources Code Regulations, and San Luis Obispo Fire Department requirements. These
regulations would ensure cumulative development would minimize the potential for wildfire to
occur within SaSan Luis Obispo. Therefore, cumulative wildfire impacts would be less than
significant.
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100
Based on the analysis above, the project would not result in a cumulatively considerable
contribution to a significant cumulative impact.
LESS-THAN-SIGNIFICANT IMPACT
c. Does the project have environmental effects which will cause substantial adverse effects on
human beings, either directly or indirectly?
Adverse effects on human beings are typically associated with air quality, hazards and hazardous
materials, noise, and wildfire impacts. These impacts are addressed in Section 3, Air Quality, Section
8, Hazards and Hazardous Materials, and Section 12, Noise. As discussed in detail in these sections,
the project would not result in substantial adverse effects to humans due to exposure to air quality
criteria pollutants in excess of established regulatory thresholds set by SLOAPCD. The project would
not result in substantial impacts related to hazards and hazardous materials. With implementation
of Mitigation Measures N-1 and N-2, the project would minimize temporary and intermittent noise
levels during construction. Therefore, the project would not have environmental effects which
would cause substantial adverse effects on human beings and this impact would be less than
significant with mitigation incorporated.
LESS THAN SIGNIFICANT WITH MITIGATION INCORPORATED
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Final Initial Study – Mitigated Negative Declaration 101
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References
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(accessed July 2024).
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https://www.envirostor.dtsc.ca.gov/public/map/?myaddress=san+luis+obispo (accessed
July 2024).
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Final Initial Study – Mitigated Negative Declaration 103
California Department of Transportation (Caltrans). 2019. California State Scenic Highway System
Map. https://dot.ca.gov/programs/design/lap-landscape-architecture-and-community-
livability/lap-liv-i-scenic-highways (accessed July 2024).
______. 2020. Transportation and Construction Vibration Guidance Manual. https://dot.ca.gov/-
/media/dot-media/programs/environmental-analysis/documents/env/tcvgm-apr2020-
a11y.pdf (accessed August 2024).
California Department of Water Resources (DWR). 2022. SGMA Basin Prioritization Dashboard.
https://gis.water.ca.gov/app/bp-dashboard/final/ (accessed July 2024).
______. 2025. Sustainable Groundwater Management Act (SGMA) Data Viewer. Accessed January 3,
2025. https://sgma.water.ca.gov/webgis/?appid=SGMADataViewer#currentconditions
California Geological Survey (CGS). 2024. EQ Zapp: California Earthquake Hazard Zones Application.
https://maps.conservation.ca.gov/cgs/EQZApp/app/ (accessed July 2024).
City of San Luis Obispo. 2014a. Land Use and Circulation Element Update Volume I Draft Program
EIR. June 2014.
https://www.slocity.org/home/showpublisheddocument/6723/635671221997970000
(accessed July 2024).
______. 2014b. Conservation and Open Space Element.
https://www.slocity.org/home/showpublisheddocument/6651/635670212786530000
(accessed July 2024).
______. 2014c. Safety Element. December 9, 2014.
https://www.slocity.org/home/showpublisheddocument/6645/635670212766530000
(accessed July 2024).
______. 2020a. Climate Action Plan For Community Recovery.
https://www.slocity.org/government/department-directory/city-administration/office-of-
sustainability-and-natural-resources/climate-action/climate-action-plan (accessed August
2024).
______. 2020b. Standard Specifications & Engineering Standards.
https://www.slocity.org/home/showpublisheddocument/27919/637341402080900000
(accessed July 2024).
______. 2020c. Transportation Impact Study Guidelines.
https://www.slocity.org/home/showpublisheddocument/26883/637290299618070000
(accessed August 2024).
______. 2021. Parks + Recreation Blueprint for the Future: 2021-2041. July 2021.
https://www.slocity.org/home/showpublisheddocument/29503/637690273249070000
(accessed July 2024).
______. 2024a. San Luis Obispo Bike Map.
https://slocity.maps.arcgis.com/apps/Viewer/index.html?appid=26dbd38b9b46474a9f067a
ce6a453fc4 (accessed August 2024).
______. 2024b. SLO Transit Rider Portal. https://slo.rider.peaktransit.com/ (accessed August 2024).
______. 2024c. Wastewater Treatment. https://www.slocity.org/government/department-
directory/utilities-department/wastewater/wastewater-treatment (accessed July 2024).
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City of San Luis Obispo
Groundwater Contamination Characterization Project
104
______. 2024d. Current Development Projects.
https://storymaps.arcgis.com/stories/d6ad7b71ca324c5b95773617e182a042 (accessed
September 2024).
______. 2024e. 2020 Urban Water Management Plan.
https://www.slocity.org/home/showpublisheddocument/31041/637673768464130000
(accessed September 2024).
City of San Luis Obispo Department of Public Works. 2022. Interactive Data Viewer.
https://gis.slocounty.ca.gov/Html5Viewer/Index.html?configBase=/Geocortex/Essentials/RE
ST/sites/PW_SGMA/viewers/PW_Viewer/virtualdirectory/Resources/Config/Default&Layer
Theme=3 (accessed July 2024).
Federal Emergency Management Agency (FEMA). 2024. National Flood Hazard Layer.
https://hazards-
fema.maps.arcgis.com/apps/webappviewer/index.html?id=8b0adb51996444d4879338b552
9aa9cd (accessed July 2024).
Jennings, C. 1958. Geologic Map of California San Luis Obispo Sheet.
https://www.conservation.ca.gov/cgs/Documents/Publications/Geologic-Atlas-
Maps/GAM_18-SanLuisObispo-1958-Map.pdf (accessed September 2024).
RS&H. 2021. Amended and Restated San Luis Obispo County Regional Airport – Airport Land Use
Plan. Accessible at: https://sloairport.com/wp-
content/uploads/2024/02/Airport_Land_Use_Plan_Amended_5-26-21.pdf (accessed July
2024).
San Luis Obispo Air Pollution Control District (SLOAPCD). 2001. Clean Air Plan.
https://storage.googleapis.com/slocleanair-
org/images/cms/upload/files/business/pdf/CAP.pdf (accessed August 2024).
______. 2005. Particulate Matter Report Implementation of SB 656 Requirements.
https://storage.googleapis.com/slocleanair-org/images/cms/upload/files/PM.ReportFin.pdf
(accessed August 2024).
______. 2018. SLO APCD NOA Screening.
https://www.google.com/maps/d/u/0/viewer?mid=1YAKjBzVkwi1bZ4rQ1p6b2OMyvIM&ll=
35.364986805363785%2C-120.52563349999998&z=10 (accessed August 2024).
______. 2019. San Luis Obispo County Attainment Status.
https://storage.googleapis.com/slocleanair-
org/images/cms/upload/files/AttainmentStatus29January2019.pdf (accessed August 2024).
______. 2020. Ozone Emergency Episode Plan. https://storage.googleapis.com/slocleanair-
org/images/cms/upload/files/San%20Luis%20Obispo%20County%20Ozone%20Emergency%
20Episode%20Plan%2022%20January%202020.pdf (accessed August 2024).
______. 2023. CEQA Air Quality Handbook. https://storage.googleapis.com/slocleanair-
org/images/cms/upload/files/CEQA%20Handbook%202023_Final.pdf (accessed August
2024).
San Luis Obispo Fire Department (SLOFD). 2023. 2023 Annual Report.
https://www.slocity.org/home/showpublisheddocument/35237/638518006009370000
(accessed July 2024).
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San Luis Obispo Police Department (SLOPD). 2024. About the Department.
https://www.slocity.org/government/department-directory/police-department/about-the-
department (accessed July 2024).
Society of Vertebrate Paleontology (SVP). 2010. Standard Procedures for the Assessment and
Mitigation of Adverse Impacts to Paleontological Resources. https://vertpaleo.org/wp-
content/uploads/2021/01/SVP_Impact_Mitigation_Guidelines-1.pdf (accessed July 2024).
State Water Resources Control Board (SWRCB). 2022. GeoTracker.
https://geotracker.waterboards.ca.gov/map/?CMD=runreport&myaddress=city+of+san+luis
+obsipo (accessed July 2024).
United States Department of Agriculture (USDA). 2024. Web Soil Survey.
https://websoilsurvey.sc.egov.usda.gov/app/WebSoilSurvey.aspx (accessed July 2024).
United States Environmental Protection Agency (U.S.EPA). 2024. Superfund Enterprise Management
System. July 1, 2024. https://enviro.epa.gov/envirofacts/sems/search (accessed July 2024).
Water Systems Consulting (WSC). 2024. Monitoring and Reporting Plan (July 2024).
List of Preparers
Rincon Consultants, Inc. prepared this IS-MND under contract to the City of San Luis Obispo. Persons
involved in data gathering analysis, project management, and quality control are listed below.
Rincon Consultants, Inc.
Richard Daulton, MURP, Vice President/Senor Principal
Megan Jones, Principal
Chris Bersbach, MESM, Senior Supervising Planner
Nik Kilpelainen, Environmental Planner
Ethan Knox, Environmental Planner
Bryan Valladares, GIS Analyst
Debra Jane Seltzer, Formatting Specialist
Page 233 of 717
Appendix A
Air Quality and Greenhouse Gas Modeling
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PCE Plume Characterization Detailed Report
Table of Contents
1. Basic Project Information
1.1. Basic Project Information
1.2. Land Use Types
1.3. User-Selected Emission Reduction Measures by Emissions Sector
2. Emissions Summary
2.1. Construction Emissions Compared Against Thresholds
2.2. Construction Emissions by Year, Unmitigated
3. Construction Emissions Details
3.1. Monitoring Well Construction (2025) - Unmitigated
3.3. Well Equipping (2025) - Unmitigated
3.5. Well Equipping (2026) - Unmitigated
3.7. TW-3 Construction (2025) - Unmitigated
3.9. TW-3 Construction (2026) - Unmitigated
3.11. TW-4 Drilling (2025) - Unmitigated
3.13. TW-4 Drilling (2026) - Unmitigated
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4. Operations Emissions Details
4.10. Soil Carbon Accumulation By Vegetation Type
4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated
4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated
4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated
5. Activity Data
5.1. Construction Schedule
5.2. Off-Road Equipment
5.2.1. Unmitigated
5.3. Construction Vehicles
5.3.1. Unmitigated
5.4. Vehicles
5.4.1. Construction Vehicle Control Strategies
5.5. Architectural Coatings
5.6. Dust Mitigation
5.6.1. Construction Earthmoving Activities
5.6.2. Construction Earthmoving Control Strategies
5.7. Construction Paving
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5.8. Construction Electricity Consumption and Emissions Factors
5.18. Vegetation
5.18.1. Land Use Change
5.18.1.1. Unmitigated
5.18.1. Biomass Cover Type
5.18.1.1. Unmitigated
5.18.2. Sequestration
5.18.2.1. Unmitigated
6. Climate Risk Detailed Report
6.1. Climate Risk Summary
6.2. Initial Climate Risk Scores
6.3. Adjusted Climate Risk Scores
6.4. Climate Risk Reduction Measures
7. Health and Equity Details
7.1. CalEnviroScreen 4.0 Scores
7.2. Healthy Places Index Scores
7.3. Overall Health & Equity Scores
7.4. Health & Equity Measures
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7.5. Evaluation Scorecard
7.6. Health & Equity Custom Measures
8. User Changes to Default Data
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1. Basic Project Information
1.1. Basic Project Information
Data Field Value
Project Name PCE Plume Characterization
Construction Start Date 1/2/2025
Lead Agency —
Land Use Scale Project/site
Analysis Level for Defaults County
Windspeed (m/s) 3.20
Precipitation (days) 26.6
Location 35.249893196861194, -120.67849021021235
County San Luis Obispo
City San Luis Obispo
Air District San Luis Obispo County APCD
Air Basin South Central Coast
TAZ 3332
EDFZ 6
Electric Utility Pacific Gas & Electric Company
Gas Utility Southern California Gas
App Version 2022.1.1.29
1.2. Land Use Types
Land Use Subtype Size Unit Lot Acreage Building Area (sq ft) Landscape Area (sq
ft)
Special Landscape
Area (sq ft)
Population Description
Other Non-Asphalt
Surfaces
30.4 Acre 30.4 0.00 0.00 — — —
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1.3. User-Selected Emission Reduction Measures by Emissions Sector
No measures selected
2. Emissions Summary
2.1. Construction Emissions Compared Against Thresholds
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Un/Mit. TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 7.43 6.25 48.0 55.7 0.16 1.70 0.18 1.88 1.57 0.04 1.61 — 17,834 17,834 0.73 0.15 0.81 17,899
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 7.43 6.25 48.0 55.7 0.16 1.70 0.18 1.88 1.57 0.04 1.61 — 17,826 17,826 0.72 0.15 0.02 17,890
Average
Daily
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 2.11 1.77 13.7 15.8 0.05 0.49 0.04 0.52 0.45 0.01 0.46 — 5,070 5,070 0.21 0.04 0.08 5,088
Annual
(Max)
— — — — — — — — — — — — — — — — — —
Unmit. 0.39 0.32 2.50 2.89 0.01 0.09 0.01 0.10 0.08 < 0.005 0.08 — 839 839 0.03 0.01 0.01 842
2.2. Construction Emissions by Year, Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Year TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Daily -
Summer
(Max)
— — — — — — — — — — — — — — — — — —
2025 7.43 6.25 48.0 55.7 0.16 1.70 0.18 1.88 1.57 0.04 1.61 — 17,834 17,834 0.73 0.15 0.81 17,899
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2026 1.77 1.48 11.3 13.9 0.04 0.39 0.00 0.39 0.36 0.00 0.36 — 4,456 4,456 0.18 0.04 0.00 4,471
Daily -
Winter
(Max)
— — — — — — — — — — — — — — — — — —
2025 7.43 6.25 48.0 55.7 0.16 1.70 0.18 1.88 1.57 0.04 1.61 — 17,826 17,826 0.72 0.15 0.02 17,890
2026 5.46 4.59 33.9 41.2 0.12 1.19 0.09 1.28 1.09 0.02 1.11 — 13,289 13,289 0.54 0.11 0.01 13,336
Average
Daily
— — — — — — — — — — — — — — — — — —
2025 2.11 1.77 13.7 15.8 0.05 0.49 0.04 0.52 0.45 0.01 0.46 — 5,070 5,070 0.21 0.04 0.08 5,088
2026 0.87 0.73 5.48 6.71 0.02 0.19 0.01 0.20 0.17 < 0.005 0.18 — 2,157 2,157 0.09 0.02 0.01 2,165
Annual — — — — — — — — — — — — — — — — — —
2025 0.39 0.32 2.50 2.89 0.01 0.09 0.01 0.10 0.08 < 0.005 0.08 — 839 839 0.03 0.01 0.01 842
2026 0.16 0.13 1.00 1.22 < 0.005 0.03 < 0.005 0.04 0.03 < 0.005 0.03 — 357 357 0.01 < 0.005 < 0.005 358
3. Construction Emissions Details
3.1. Monitoring Well Construction (2025) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.80 1.51 12.0 13.9 0.04 0.42 — 0.42 0.39 — 0.39 — 4,451 4,451 0.18 0.04 — 4,467
Dust
From
Material
Movement
— — — — — — < 0.005 < 0.005 — < 0.005 < 0.005 — — — — — — —
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0.000.000.000.000.000.00—0.000.000.000.000.000.000.000.000.000.000.00Onsite
truck
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.80 1.51 12.0 13.9 0.04 0.42 — 0.42 0.39 — 0.39 — 4,451 4,451 0.18 0.04 — 4,467
Dust
From
Material
Movement
— — — — — — < 0.005 < 0.005 — < 0.005 < 0.005 — — — — — — —
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.25 0.21 1.64 1.91 0.01 0.06 — 0.06 0.05 — 0.05 — 610 610 0.02 < 0.005 — 612
Dust
From
Material
Movement
— — — — — — < 0.005 < 0.005 — < 0.005 < 0.005 — — — — — — —
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.04 0.04 0.30 0.35 < 0.005 0.01 — 0.01 0.01 — 0.01 — 101 101 < 0.005 < 0.005 — 101
Dust
From
Material
Movement
— — — — — — < 0.005 < 0.005 — < 0.005 < 0.005 — — — — — — —
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
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Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.06 0.04 0.49 0.00 0.00 0.09 0.09 0.00 0.02 0.02 — 91.4 91.4 0.01 < 0.005 0.38 93.2
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 8.77 8.77 < 0.005 < 0.005 0.02 9.21
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.06 0.04 0.48 0.00 0.00 0.09 0.09 0.00 0.02 0.02 — 87.6 87.6 < 0.005 < 0.005 0.01 88.9
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 8.77 8.77 < 0.005 < 0.005 < 0.005 9.20
Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.01 0.01 0.01 0.06 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 12.1 12.1 < 0.005 < 0.005 0.02 12.3
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 1.20 1.20 < 0.005 < 0.005 < 0.005 1.26
Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 2.00 2.00 < 0.005 < 0.005 < 0.005 2.03
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 0.20 0.20 < 0.005 < 0.005 < 0.005 0.21
3.3. Well Equipping (2025) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
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4,467—0.040.184,4514,451—0.39—0.390.42—0.420.0413.912.01.511.80Off-Roa
d
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.80 1.51 12.0 13.9 0.04 0.42 — 0.42 0.39 — 0.39 — 4,451 4,451 0.18 0.04 — 4,467
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.75 0.63 4.99 5.80 0.02 0.18 — 0.18 0.16 — 0.16 — 1,855 1,855 0.08 0.02 — 1,862
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.14 0.11 0.91 1.06 < 0.005 0.03 — 0.03 0.03 — 0.03 — 307 307 0.01 < 0.005 — 308
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
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Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
3.5. Well Equipping (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.77 1.48 11.3 13.9 0.04 0.39 — 0.39 0.36 — 0.36 — 4,456 4,456 0.18 0.04 — 4,471
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
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Off-Roa
Equipment
1.77 1.48 11.3 13.9 0.04 0.39 — 0.39 0.36 — 0.36 — 4,456 4,456 0.18 0.04 — 4,471
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.63 0.53 4.01 4.95 0.01 0.14 — 0.14 0.13 — 0.13 — 1,587 1,587 0.06 0.01 — 1,592
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.11 0.10 0.73 0.90 < 0.005 0.03 — 0.03 0.02 — 0.02 — 263 263 0.01 < 0.005 — 264
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
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Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
3.7. TW-3 Construction (2025) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.90 1.60 12.0 13.0 0.04 0.44 — 0.44 0.41 — 0.41 — 4,276 4,276 0.17 0.03 — 4,291
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.90 1.60 12.0 13.0 0.04 0.44 — 0.44 0.41 — 0.41 — 4,276 4,276 0.17 0.03 — 4,291
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
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1,260—0.010.051,2551,255—0.12—0.120.13—0.130.013.813.520.470.56Off-Roa
d
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.10 0.09 0.64 0.70 < 0.005 0.02 — 0.02 0.02 — 0.02 — 208 208 0.01 < 0.005 — 209
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
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Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
3.9. TW-3 Construction (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.87 1.57 11.3 12.9 0.04 0.41 — 0.41 0.38 — 0.38 — 4,279 4,279 0.17 0.03 — 4,294
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.12 0.10 0.73 0.84 < 0.005 0.03 — 0.03 0.02 — 0.02 — 276 276 0.01 < 0.005 — 277
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.02 0.02 0.13 0.15 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 45.8 45.8 < 0.005 < 0.005 — 45.9
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Offsite — — — — — — — — — — — — — — — — — —
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Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Worker 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
3.11. TW-4 Drilling (2025) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.80 1.51 12.0 13.9 0.04 0.42 — 0.42 0.39 — 0.39 — 4,451 4,451 0.18 0.04 — 4,467
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———————< 0.005< 0.005—< 0.005< 0.005——————Dust
From
Material
Movement
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.80 1.51 12.0 13.9 0.04 0.42 — 0.42 0.39 — 0.39 — 4,451 4,451 0.18 0.04 — 4,467
Dust
From
Material
Movement
— — — — — — < 0.005 < 0.005 — < 0.005 < 0.005 — — — — — — —
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.53 0.44 3.51 4.09 0.01 0.12 — 0.12 0.11 — 0.11 — 1,307 1,307 0.05 0.01 — 1,311
Dust
From
Material
Movement
— — — — — — < 0.005 < 0.005 — < 0.005 < 0.005 — — — — — — —
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.10 0.08 0.64 0.75 < 0.005 0.02 — 0.02 0.02 — 0.02 — 216 216 0.01 < 0.005 — 217
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———————< 0.005< 0.005—< 0.005< 0.005——————Dust
From
Material
Movement
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.06 0.04 0.49 0.00 0.00 0.09 0.09 0.00 0.02 0.02 — 91.4 91.4 0.01 < 0.005 0.38 93.2
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 12.2 12.2 < 0.005 < 0.005 0.02 12.8
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.06 0.04 0.48 0.00 0.00 0.09 0.09 0.00 0.02 0.02 — 87.6 87.6 < 0.005 < 0.005 0.01 88.9
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 12.2 12.2 < 0.005 < 0.005 < 0.005 12.8
Average
Daily
— — — — — — — — — — — — — — — — — —
Worker 0.02 0.02 0.01 0.14 0.00 0.00 0.02 0.02 0.00 0.01 0.01 — 25.9 25.9 < 0.005 < 0.005 0.05 26.3
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 3.57 3.57 < 0.005 < 0.005 < 0.005 3.75
Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.03 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 4.29 4.29 < 0.005 < 0.005 0.01 4.36
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 0.59 0.59 < 0.005 < 0.005 < 0.005 0.62
3.13. TW-4 Drilling (2026) - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
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Location TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Onsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
1.77 1.48 11.3 13.9 0.04 0.39 — 0.39 0.36 — 0.36 — 4,456 4,456 0.18 0.04 — 4,471
Dust
From
Material
Movement
— — — — — — < 0.005 < 0.005 — < 0.005 < 0.005 — — — — — — —
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Average
Daily
— — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.11 0.10 0.73 0.90 < 0.005 0.03 — 0.03 0.02 — 0.02 — 288 288 0.01 < 0.005 — 289
Dust
From
Material
Movement
— — — — — — < 0.005 < 0.005 — < 0.005 < 0.005 — — — — — — —
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Annual — — — — — — — — — — — — — — — — — —
Off-Roa
d
Equipm
ent
0.02 0.02 0.13 0.16 < 0.005 < 0.005 — < 0.005 < 0.005 — < 0.005 — 47.6 47.6 < 0.005 < 0.005 — 47.8
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———————< 0.005< 0.005—< 0.005< 0.005——————Dust
From
Material
Movement
Onsite
truck
0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Offsite — — — — — — — — — — — — — — — — — —
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Worker 0.06 0.06 0.04 0.45 0.00 0.00 0.09 0.09 0.00 0.02 0.02 — 86.1 86.1 < 0.005 < 0.005 0.01 87.3
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 0.02 0.01 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 11.9 11.9 < 0.005 < 0.005 < 0.005 12.5
Average
Daily
— — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.03 0.00 0.00 0.01 0.01 0.00 < 0.005 < 0.005 — 5.60 5.60 < 0.005 < 0.005 0.01 5.69
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 0.77 0.77 < 0.005 < 0.005 < 0.005 0.81
Annual — — — — — — — — — — — — — — — — — —
Worker < 0.005 < 0.005 < 0.005 0.01 0.00 0.00 < 0.005 < 0.005 0.00 < 0.005 < 0.005 — 0.93 0.93 < 0.005 < 0.005 < 0.005 0.94
Vendor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 — 0.00 0.00 0.00 0.00 0.00 0.00
Hauling < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 < 0.005 — 0.13 0.13 < 0.005 < 0.005 < 0.005 0.13
4. Operations Emissions Details
4.10. Soil Carbon Accumulation By Vegetation Type
4.10.1. Soil Carbon Accumulation By Vegetation Type - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)Page 254 of 717
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Vegetati TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
4.10.2. Above and Belowground Carbon Accumulation by Land Use Type - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Land
Use
TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
Daily,
Summer
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Total — — — — — — — — — — — — — — — — — —
4.10.3. Avoided and Sequestered Emissions by Species - Unmitigated
Criteria Pollutants (lb/day for daily, ton/yr for annual) and GHGs (lb/day for daily, MT/yr for annual)
Species TOG ROG NOx CO SO2 PM10E PM10D PM10T PM2.5E PM2.5D PM2.5T BCO2 NBCO2 CO2T CH4 N2O R CO2e
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——————————————————Daily,
Summer
(Max)
Avoided — — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Sequest
ered
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Remove
d
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
— — — — — — — — — — — — — — — — — — —
Daily,
Winter
(Max)
— — — — — — — — — — — — — — — — — —
Avoided — — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Sequest
ered
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Remove
d
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
— — — — — — — — — — — — — — — — — — —
Annual — — — — — — — — — — — — — — — — — —
Avoided — — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Sequest
ered
— — — — — — — — — — — — — — — — — —
Subtotal — — — — — — — — — — — — — — — — — —
Remove
d
— — — — — — — — — — — — — — — — — —
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Subtotal — — — — — — — — — — — — — — — — — —
— — — — — — — — — — — — — — — — — — —
5. Activity Data
5.1. Construction Schedule
Phase Name Phase Type Start Date End Date Days Per Week Work Days per Phase Phase Description
Monitoring Well
Construction
Building Construction 4/1/2025 10/1/2025 5.00 50.0 —
Well Equipping Building Construction 6/2/2025 7/1/2026 5.00 84.0 —
TW-3 Construction Building Construction 8/4/2025 2/2/2026 5.00 50.0 —
TW-4 Drilling Trenching 8/4/2025 2/2/2026 5.00 36.0 —
5.2. Off-Road Equipment
5.2.1. Unmitigated
Phase Name Equipment Type Fuel Type Engine Tier Number per Day Hours Per Day Horsepower Load Factor
Monitoring Well
Construction
Bore/Drill Rigs Diesel Average 1.00 8.00 83.0 0.50
Monitoring Well
Construction
Cement and Mortar
Mixers
Diesel Average 1.00 8.00 10.0 0.56
Monitoring Well
Construction
Off-Highway Trucks Diesel Average 2.00 8.00 376 0.38
Monitoring Well
Construction
Cranes Diesel Average 1.00 8.00 367 0.29
Monitoring Well
Construction
Rough Terrain Forklifts Diesel Average 1.00 8.00 96.0 0.40
Well Equipping Cement and Mortar
Mixers
Diesel Average 1.00 8.00 10.0 0.56
Well Equipping Off-Highway Trucks Diesel Average 2.00 8.00 376 0.38
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Well Equipping Cranes Diesel Average 1.00 8.00 367 0.29
Well Equipping Rough Terrain Forklifts Diesel Average 1.00 8.00 96.0 0.40
Well Equipping Bore/Drill Rigs Diesel Average 1.00 8.00 83.0 0.50
TW-3 Construction Cement and Mortar
Mixers
Diesel Average 1.00 8.00 10.0 0.56
TW-3 Construction Off-Highway Trucks Diesel Average 2.00 8.00 376 0.38
TW-3 Construction Cranes Diesel Average 1.00 8.00 367 0.29
TW-3 Construction Rough Terrain Forklifts Diesel Average 1.00 8.00 96.0 0.40
TW-3 Construction Trenchers Diesel Average 1.00 8.00 40.0 0.50
TW-4 Drilling Bore/Drill Rigs Diesel Average 1.00 8.00 83.0 0.50
TW-4 Drilling Cement and Mortar
Mixers
Diesel Average 1.00 8.00 10.0 0.56
TW-4 Drilling Off-Highway Trucks Diesel Average 2.00 8.00 376 0.38
TW-4 Drilling Cranes Diesel Average 1.00 8.00 367 0.29
TW-4 Drilling Rough Terrain Forklifts Diesel Average 1.00 8.00 96.0 0.40
5.3. Construction Vehicles
5.3.1. Unmitigated
Phase Name Trip Type One-Way Trips per Day Miles per Trip Vehicle Mix
TW-4 Drilling — — — —
TW-4 Drilling Worker 15.0 8.10 LDA,LDT1,LDT2
TW-4 Drilling Vendor — 6.90 HHDT,MHDT
TW-4 Drilling Hauling 0.17 20.0 HHDT
TW-4 Drilling Onsite truck — — HHDT
Monitoring Well Construction — — — —
Monitoring Well Construction Worker 15.0 8.10 LDA,LDT1,LDT2
Monitoring Well Construction Vendor 0.00 6.90 HHDT,MHDT
Monitoring Well Construction Hauling 0.12 20.0 HHDT Page 258 of 717
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Monitoring Well Construction Onsite truck — — HHDT
Well Equipping — — — —
Well Equipping Worker 0.00 8.10 LDA,LDT1,LDT2
Well Equipping Vendor 0.00 6.90 HHDT,MHDT
Well Equipping Hauling 0.00 20.0 HHDT
Well Equipping Onsite truck — — HHDT
TW-3 Construction — — — —
TW-3 Construction Worker 0.00 10.8 LDA,LDT1,LDT2
TW-3 Construction Vendor 0.00 6.85 HHDT,MHDT
TW-3 Construction Hauling 0.00 20.0 HHDT
TW-3 Construction Onsite truck — — HHDT
5.4. Vehicles
5.4.1. Construction Vehicle Control Strategies
Non-applicable. No control strategies activated by user.
5.5. Architectural Coatings
Phase Name Residential Interior Area
Coated (sq ft)
Residential Exterior Area
Coated (sq ft)
Non-Residential Interior Area
Coated (sq ft)
Non-Residential Exterior Area
Coated (sq ft)
Parking Area Coated (sq ft)
5.6. Dust Mitigation
5.6.1. Construction Earthmoving Activities
Phase Name Material Imported (Cubic
Yards)
Material Exported (Cubic
Yards)
Acres Graded (acres) Material Demolished (sq. ft.) Acres Paved (acres)
Monitoring Well Construction 0.00 48.0 8.40 0.00 —
TW-4 Drilling 0.00 45.0 22.0 0.00 —
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5.6.2. Construction Earthmoving Control Strategies
Non-applicable. No control strategies activated by user.
5.7. Construction Paving
Land Use Area Paved (acres) % Asphalt
Other Non-Asphalt Surfaces 30.4 0%
5.8. Construction Electricity Consumption and Emissions Factors
kWh per Year and Emission Factor (lb/MWh)
Year kWh per Year CO2 CH4 N2O
2025 0.00 204 0.03 < 0.005
2026 0.00 204 0.03 < 0.005
5.18. Vegetation
5.18.1. Land Use Change
5.18.1.1. Unmitigated
Vegetation Land Use Type Vegetation Soil Type Initial Acres Final Acres
5.18.1. Biomass Cover Type
5.18.1.1. Unmitigated
Biomass Cover Type Initial Acres Final Acres
5.18.2. Sequestration
5.18.2.1. Unmitigated
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Tree Type Number Electricity Saved (kWh/year) Natural Gas Saved (btu/year)
6. Climate Risk Detailed Report
6.1. Climate Risk Summary
Cal-Adapt midcentury 2040–2059 average projections for four hazards are reported below for your project location. These are under Representation Concentration Pathway (RCP) 8.5 which
assumes GHG emissions will continue to rise strongly through 2050 and then plateau around 2100.
Climate Hazard Result for Project Location Unit
Temperature and Extreme Heat 8.08 annual days of extreme heat
Extreme Precipitation 5.60 annual days with precipitation above 20 mm
Sea Level Rise — meters of inundation depth
Wildfire 49.2 annual hectares burned
Temperature and Extreme Heat data are for grid cell in which your project are located. The projection is based on the 98th historical percentile of daily maximum/minimum temperatures from
observed historical data (32 climate model ensemble from Cal-Adapt, 2040–2059 average under RCP 8.5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.
Extreme Precipitation data are for the grid cell in which your project are located. The threshold of 20 mm is equivalent to about ¾ an inch of rain, which would be light to moderate rainfall if
received over a full day or heavy rain if received over a period of 2 to 4 hours. Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.
Sea Level Rise data are for the grid cell in which your project are located. The projections are from Radke et al. (2017), as reported in Cal-Adapt (Radke et al., 2017, CEC-500-2017-008), and
consider inundation location and depth for the San Francisco Bay, the Sacramento-San Joaquin River Delta and California coast resulting different increments of sea level rise coupled with
extreme storm events. Users may select from four scenarios to view the range in potential inundation depth for the grid cell. The four scenarios are: No rise, 0.5 meter, 1.0 meter, 1.41 meters
Wildfire data are for the grid cell in which your project are located. The projections are from UC Davis, as reported in Cal-Adapt (2040–2059 average under RCP 8.5), and consider historical data
of climate, vegetation, population density, and large (> 400 ha) fire history. Users may select from four model simulations to view the range in potential wildfire probabilities for the grid cell. The
four simulations make different assumptions about expected rainfall and temperature are: Warmer/drier (HadGEM2-ES), Cooler/wetter (CNRM-CM5), Average conditions (CanESM2), Range of
different rainfall and temperature possibilities (MIROC5). Each grid cell is 6 kilometers (km) by 6 km, or 3.7 miles (mi) by 3.7 mi.
6.2. Initial Climate Risk Scores
Climate Hazard Exposure Score Sensitivity Score Adaptive Capacity Score Vulnerability Score
Temperature and Extreme Heat N/A N/A N/A N/A
Extreme Precipitation N/A N/A N/A N/A
Sea Level Rise N/A N/A N/A N/A
Wildfire N/A N/A N/A N/A
Flooding N/A N/A N/A N/A
Drought N/A N/A N/A N/A
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Snowpack Reduction N/A N/A N/A N/A
Air Quality Degradation N/A N/A N/A N/A
The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the
greatest exposure.
The adaptive capacity of a project refers to its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5
representing the greatest ability to adapt.
The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores do not include implementation of climate risk reduction
measures.
6.3. Adjusted Climate Risk Scores
Climate Hazard Exposure Score Sensitivity Score Adaptive Capacity Score Vulnerability Score
Temperature and Extreme Heat N/A N/A N/A N/A
Extreme Precipitation N/A N/A N/A N/A
Sea Level Rise N/A N/A N/A N/A
Wildfire N/A N/A N/A N/A
Flooding N/A N/A N/A N/A
Drought N/A N/A N/A N/A
Snowpack Reduction N/A N/A N/A N/A
Air Quality Degradation N/A N/A N/A N/A
The sensitivity score reflects the extent to which a project would be adversely affected by exposure to a climate hazard. Exposure is rated on a scale of 1 to 5, with a score of 5 representing the
greatest exposure.
The adaptive capacity of a project refers to its ability to manage and reduce vulnerabilities from projected climate hazards. Adaptive capacity is rated on a scale of 1 to 5, with a score of 5
representing the greatest ability to adapt.
The overall vulnerability scores are calculated based on the potential impacts and adaptive capacity assessments for each hazard. Scores include implementation of climate risk reduction
measures.
6.4. Climate Risk Reduction Measures
7. Health and Equity Details
7.1. CalEnviroScreen 4.0 Scores
The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state.
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Indicator Result for Project Census Tract
Exposure Indicators —
AQ-Ozone 13.6
AQ-PM 12.8
AQ-DPM 66.6
Drinking Water 74.4
Lead Risk Housing 29.3
Pesticides 88.0
Toxic Releases 24.5
Traffic 92.0
Effect Indicators —
CleanUp Sites 11.8
Groundwater 55.6
Haz Waste Facilities/Generators 80.2
Impaired Water Bodies 66.7
Solid Waste 0.00
Sensitive Population —
Asthma 40.6
Cardio-vascular 16.8
Low Birth Weights 10.6
Socioeconomic Factor Indicators —
Education 53.1
Housing 21.1
Linguistic 43.9
Poverty 63.8
Unemployment 35.0
7.2. Healthy Places Index Scores
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The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.
Indicator Result for Project Census Tract
Economic —
Above Poverty 52.3675093
Employed 18.46528936
Median HI 43.83421019
Education —
Bachelor's or higher 65.64865905
High school enrollment 100
Preschool enrollment 38.90671115
Transportation —
Auto Access 73.42486847
Active commuting 68.02258437
Social —
2-parent households 89.83703323
Voting 78.12139099
Neighborhood —
Alcohol availability 58.37289876
Park access 81.35506224
Retail density 34.12036443
Supermarket access 79.9563711
Tree canopy 49.72411138
Housing —
Homeownership 62.4534839
Housing habitability 80.1360195
Low-inc homeowner severe housing cost burden 27.39638137
Low-inc renter severe housing cost burden 91.45386886
Uncrowded housing 62.10701912
Health Outcomes —
I
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Insured adults 46.18247145
Arthritis 0.0
Asthma ER Admissions 78.8
High Blood Pressure 0.0
Cancer (excluding skin) 0.0
Asthma 0.0
Coronary Heart Disease 0.0
Chronic Obstructive Pulmonary Disease 0.0
Diagnosed Diabetes 0.0
Life Expectancy at Birth 14.9
Cognitively Disabled 6.9
Physically Disabled 13.7
Heart Attack ER Admissions 86.7
Mental Health Not Good 0.0
Chronic Kidney Disease 0.0
Obesity 0.0
Pedestrian Injuries 19.6
Physical Health Not Good 0.0
Stroke 0.0
Health Risk Behaviors —
Binge Drinking 0.0
Current Smoker 0.0
No Leisure Time for Physical Activity 0.0
Climate Change Exposures —
Wildfire Risk 0.0
SLR Inundation Area 0.0
Children 64.0
Elderly 23.5
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English Speaking 69.5
Foreign-born 29.5
Outdoor Workers 48.7
Climate Change Adaptive Capacity —
Impervious Surface Cover 60.0
Traffic Density 63.3
Traffic Access 0.0
Other Indices —
Hardship 33.2
Other Decision Support —
2016 Voting 80.2
7.3. Overall Health & Equity Scores
Metric Result for Project Census Tract
CalEnviroScreen 4.0 Score for Project Location (a) 37.0
Healthy Places Index Score for Project Location (b) 60.0
Project Located in a Designated Disadvantaged Community (Senate Bill 535) No
Project Located in a Low-Income Community (Assembly Bill 1550) No
Project Located in a Community Air Protection Program Community (Assembly Bill 617) No
a: The maximum CalEnviroScreen score is 100. A high score (i.e., greater than 50) reflects a higher pollution burden compared to other census tracts in the state.
b: The maximum Health Places Index score is 100. A high score (i.e., greater than 50) reflects healthier community conditions compared to other census tracts in the state.
7.4. Health & Equity Measures
No Health & Equity Measures selected.
7.5. Evaluation Scorecard
Health & Equity Evaluation Scorecard not completed.
7.6. Health & Equity Custom Measures
No Health & Equity Custom Measures created.Page 266 of 717
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8. User Changes to Default Data
Screen Justification
Construction: Construction Phases City-provided schedule. Assumes 36 days of drilling for TW-4, and an estimated 50 days for
monitoring wells and TW-3 construction, and 84 working days for well equipping.
Construction: Off-Road Equipment City-provided equipment list. The bucket auger drill rig is modeled as a bore/drill rig. The
cement truck and concrete pump is modeled as an off-highway truck and cement and mortar
mixer. The hollow-stem auger or rotary sonic drill is modeled as a crane. The support/water and
decontamination truck is modeled as an off-highway truck.
Construction: Dust From Material Movement Each monitoring well site would generate approximately 4 cubic yards of drill cuttings. 4 cubic
yards x 12 monitoring well sites = 48 cubic yards. TW-4 would require 45 cubic yards of drill
cuttings. In total, 93 cubic yards of cut would occur.
Construction: Trips and VMT Monitoring Well Construction workers increased to 15 to match CalEEMod defaults for the Well
Equipping and TW-4 Drilling phases.
Page 267 of 717
Appendix B
Botanical Memorandum
Page 268 of 717
Rincon Consultants, Inc.
1530 Monterey Street, Suite D
San Luis Obispo, California 93401
805-547-0900
www.rinconcons ultan ts.com
June 18, 2024
Project No: 24-15910
Shawna Scott
Special Projects Manager
City of San Luis Obispo
Public Utilities Department
879 Morro Street
San Luis Obispo, California 93401
Via email: sscott@slocity.org
Subject: Botanical Survey Memorandum for the PCE Plume Characterization Project,
City of San Luis Obispo, California
Dear Ms. Scott,
Rincon Consultants, Inc. (Rincon) is pleased to submit this Botanical Survey Memorandum (memo) for
the Tetrachloroethylene (PCE) Plume Characterization Project (Project) to the City of San Luis Obispo
(City). Rincon biologist Frances McKechnie conducted protocol-level botanical surveys to determine
presence or absence of federally and/or State-listed or other special-status plant species within the
Project site. This memo summarizes the methodology and results of the botanical survey effort.
Project Location
The Project is located within the City of San Luis Obispo in San Luis Obispo County, California. The
Project site is located in the southern portion of the City along U.S. Highway 101 (US 101) between
Prado Road and Los Osos Valley Road within Assessor’s Parcel Numbers 053-051-045, 053-052-045,
053-131-013, 053-141-012, 053-152-006, 053-152-008, 053-153-014, and 053-153-008 (Figure
1). The Project occurs within the San Luis Obispo, California and Pismo Beach, California United States
Geological Survey (USGS) 7.5-minute topographic quadrangles and is associated with Township 31S,
Range 12E, Sections 3 and 10, Mt. Diablo Meridian. The study area for this Project encompasses
approximately 18.1 acres and includes the entirety of the Project site except for the California
Department of Transportation right-of-way (Figure 1).
Methodology
Literature Review
Rincon conducted a literature review to determine the potential for federally and State-listed, as well
as special-status plant species, to occur within the study area. Queries of the California Department
of Fish and Wildlife (CDFW) California Natural Diversity Database (CNDDB; 2024) and California Native
Plant Society (CNPS) Rare Plant Inventory (2024) were conducted to obtain comprehensive
information regarding federally and State-listed species, and other special-status species, considered
to have potential to occur within the San Luis Obispo, California and Pismo Beach, California USGS
7.5-minute topographic quadrangles and the surrounding eight quadrangles (Port San Luis, Morro Bay
South, Morro Bay North, Atascadero, Santa Margarita, Lopez Mountain, Arroyo Grande NE, and
Oceano). The final list of special-status plant species with potential to occur on-site was evaluated
RINCON CONSULTANTS,INC.SINCE 1994
Page 269 of 717
City of San Luis Obispo
PCE Plume Characterization Project
2
based on presence of suitable habitat and documented occurrences within the eight-quadrangle
search area. The evaluation results and justification were compiled into a table (Attachment 1).
Surveys
Rincon conducted protocol-level botanical surveys to determine presence or absence of any federally
and/or State-listed or other special-status plant species in accordance with Botanical Survey
Guidelines (CNPS 2001) and Protocols for Surveying and Evaluating Impacts to Special Status Native
Plant Populations and Natural Communities (CDFW 2018). Rincon biologist Frances McKechnie
conducted the botanical surveys on April 26 and June 5, 2024. The details regarding the weather
conditions on-site during these surveys are provided in Table 1 below.
Table 1 Botanical Survey Conditions
Date Time
Temperature Range
(°Fahrenheit)
Average Wind Speed
(miles per hour)
Average Cloud Cover
(%)
April 26, 2024 0900-1330 60-64 1-15 50
June 5, 2024 0900-1200 64-78 2-8 0
The botanical surveys were floristic in nature; meaning that all vascular plant species encountered on-
site were identified to the lowest possible taxonomic level required to determine the presence or
absence and phenological stage (e.g., vegetative, flowering, fruiting) of special-status plant species.
The botanical surveys were timed to capture the flowering periods of all special-status plant species
determined to have a low, moderate, or high potential to occur on-site based on the literature review
and regionally specific knowledge. The surveys were conducted using systematic field techniques by
walking parallel transects through the entire study area. Special attention was given to areas with a
high potential to support special-status species (e.g., north-facing slopes, vegetation community
interfaces, areas with unique soils, and other attributes required of species that have been previously
documented). Locations of special-status plant species, if encountered, were recorded using a Geode
Global Positioning System unit with sub-meter accuracy. The Jepson Manual: Vascular Plants of
California, Second Edition (Baldwin et al. 2012), Vascular Plants of San Luis Obispo County, California,
Second Edition (Keil and Hoover 2022), and a 10x hand lens aided in confirmation of species identity
in the field. Identification of collected specimens was confirmed in the laboratory with a dissecting
microscope. The results of the botanical surveys are discussed below.
Results
No federally or State-listed or other special-status plant species were observed during the
appropriately-timed botanical surveys. A floral compendium including all vascular plant species
observed during the botanical surveys is provided in Attachment 2. Site photographs taken during the
botanical surveys are included in Attachment 3.
Thank you for the continued opportunity to work with you on this Project. Please contact us if you have
any questions or concerns regarding the information presented herein.
Sincerely,
Rincon Consultants, Inc.
Frances McKechnie Michael Tom, MS
Biologist Senior Biologist
Page 270 of 717
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PCE Plume Characterization Project
3
Attachments
Figure 1 Project Site and Study Area
Attachment 1 Special-Status Plant Species Evaluation Table
Attachment 2 Floral Compendium
Attachment 3 Site Photographs
Page 271 of 717
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PCE Plume Characterization Project
4
References
Baldwin, B.G., D.H. Goldman, D.J. Keil, R.W. Patterson, T.J. Rosatti, and D.H. Wilkin (eds). 2012. The
Jepson Manual: Vascular Plants of California, Second Edition. University of California Press.
Berkeley, California.
California Department of Fish and Wildlife (CDFW). 2018. Protocols for Surveying and Evaluating
Impacts to Special Status Native Plant Populations and Natural Communities. Available at:
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=18959&inline. Accessed April 2024.
______. 2024. California Natural Diversity Database (CNDDB), Rarefind V. Accessed April 2024.
California Native Plant Society (CNPS). 2001. Botanical Survey Guidelines. Available at:
http://www.cnps.org/cnps/rareplants/pdf/cnps_survey_guidelines.pdf. Accessed April
2024.
_______. 2024. Rare Plant Inventory (v9.5). Available at: https://www.rareplants.cnps.org. Accessed
April 2024.
Keil, D.J., and R.F Hoover. 2022. Vascular Plants of San Luis Obispo County, California, Second
Edition. Pacific Street Publishing. San Luis Obispo, California.
Page 272 of 717
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PCE Plume Characterization Project
5
Figure 1 Project Site and Study Area
Fig X Project Site
Page 273 of 717
Attachment 1
Special-Status Plant Species Evaluation Table
Page 274 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-1
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Abronia maritima
red sand-verbena
None/None
G4/S3?
4.2
Perennial herb. Coastal dunes. Dune plant. Elevations: 0-330ft. (0-100m.) Blooms Feb-Nov.Does Not Occur No suitable habitat is present within the study area.
Agrostis hooveri
Hoover's bent grass
None/None
G2/S2
1B.2
Perennial herb. Chaparral, cismontane woodland, closed-cone coniferous forest, valley and
foothill grassland. Sandy (usually). Elevations: 20-2000ft. (6-610m.) Blooms Apr-Jul.
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area. The
closest CNDDB record is from 1980 and is located approximately 3.5 miles south of the study
area. This species was not observed within the study area during April or June botanical
surveys. This species is not expected to occur on site.
Amsinckia douglasiana
Douglas' fiddleneck
None/None
G4/S4
4.2
Annual herb. Cismontane woodland, valley and foothill grassland. Dry. Elevations: 0-6400ft.
(0-1950m.) Blooms Mar-May.
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area. No
CNDDB or CNPS records occur within 5 miles of the study area. This species was not observed
within the study area during April or June botanical surveys. This species is not expected to
occur on site.
Arctostaphylos luciana
Santa Lucia manzanita
None/None
G2/S2
1B.2
Perennial evergreen shrub. Chaparral, cismontane woodland. Shale. Elevations: 1150-
2790ft. (350-850m.) Blooms Dec-Mar.
Does Not Occur The study area is located outside the known elevation range of this species.
Arctostaphylos morroensis
Morro manzanita
FT/None
G1/S1
1B.1
Perennial evergreen shrub. Chaparral, cismontane woodland, coastal dunes, coastal scrub.
On baywood sands, usually with chaparral associates. Elevations: 15-675ft. (5-205m.)
Blooms Dec-Mar.
Does Not Occur The study area is located outside the known range of this species.
Arctostaphylos obispoensis
Bishop manzanita
None/None
G3/S3
4.3
Perennial evergreen shrub. Chaparral, cismontane woodland, closed-cone coniferous forest.
Rocky, serpentinite. Elevations: 490-3295ft. (150-1005m.) Blooms Feb-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Arctostaphylos osoensis
Oso manzanita
None/None
G1/S1
1B.2
Perennial evergreen shrub. Chaparral, cismontane woodland. Usually occurs in openings
w/in oak woodland on dacite porphyry buttes. Elevations: 310-1640ft. (95-500m.) Blooms
Feb-Mar.
Does Not Occur The study area is located outside the known elevation range of this species.
Arctostaphylos pechoensis
Pecho manzanita
None/None
G2/S2
1B.2
Perennial evergreen shrub. Chaparral, closed-cone coniferous forest, coastal scrub. Grows
on siliceous shale with other chaparral associates. Elevations: 410-2790ft. (125-850m.)
Blooms Nov-Mar.
Does Not Occur The study area is located outside the known elevation range of this species.
Arctostaphylos pilosula
Santa Margarita manzanita
None/None
G2?/S2?
1B.2
Perennial evergreen shrub. Broadleafed upland forest, chaparral, cismontane woodland,
closed-cone coniferous forest. Sandstone (sometimes). Elevations: 245-3610ft. (75-
1100m.) Blooms Dec-May.
Does Not Occur The study area is located outside the known elevation range of this species.
Arctostaphylos rudis
sand mesa manzanita
None/None
G2/S2
1B.2
Perennial evergreen shrub. Chaparral, coastal scrub. Sandy. Elevations: 80-1055ft. (25-
322m.) Blooms Nov-Feb.
Low Potential Marginally suitable coastal scrub habitat is present within the study area. No CNDDB or CNPS
records occur within 5 miles of the study area. This species was not observed within the study
area during April or June botanical surveys. This species is not expected to occur on site.
Arctostaphylos tomentosa ssp.
daciticola
dacite manzanita
None/None
G4T1/S1
1B.1
Perennial evergreen shrub. Chaparral, cismontane woodland. Only known from one site in
SLO County on dacite porphyry buttes. About 120m. Elevations: 330-985ft. (100-300m.)
Blooms Mar-May.
Does Not Occur The study area is located outside the known elevation range of this species.
Arenaria paludicola
marsh sandwort
FE/SE
G1/S1
1B.1
Perennial stoloniferous herb. Marshes and swamps. Openings, sandy. Elevations: 10-560ft.
(3-170m.) Blooms May-Aug.
Does Not Occur No suitable habitat is present within the study area.
Aspidotis carlotta-halliae
Carlotta Hall's lace fern
None/None
G3/S3
4.2
Perennial rhizomatous herb. Chaparral, cismontane woodland. Serpentinite (usually).
Elevations: 330-4595ft. (100-1400m.) Blooms Jan-Dec.
Does Not Occur The study area is located outside the known elevation range of this species.
Astragalus didymocarpus var.
milesianus
Miles' milk-vetch
None/None
G5T2/S2
1B.2
Annual herb. Coastal scrub. Clay soils. Elevations: 65-295ft. (20-90m.) Blooms Mar-Jun. Low Potential Marginally suitable coastal scrub habitat is present within the study area. The closest CNDDB
record is from 2016 and is located approximately 1.1 miles northeast of the study area. This
species was not observed within the study area during April or June botanical surveys. This
species is not expected to occur on site.
Astragalus nuttallii var. nuttallii
ocean bluff milk-vetch
None/None
G4T4/S4
4.2
Perennial herb. Coastal bluff scrub, coastal dunes. Elevations: 10-395ft. (3-120m.) Blooms
Jan-Nov.
Does Not Occur No suitable habitat is present within the study area.
Page 275 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-2
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Atriplex coulteri
Coulter's saltbush
None/None
G3/S1S2
1B.2
Perennial herb. Coastal bluff scrub, coastal dunes, coastal scrub, valley and foothill
grassland. Alkaline (sometimes), clay (sometimes). Elevations: 10-1510ft. (3-460m.)
Blooms Mar-Oct.
Does Not Occur The study area is located outside the known range of this species.
Calandrinia breweri
Brewer's calandrinia
None/None
G4/S4
4.2
Annual herb. Chaparral, coastal scrub. Burned areas, disturbed areas, loam (sometimes),
sandy (sometimes). Elevations: 35-4005ft. (10-1220m.) Blooms (Jan)Mar-Jun.
Low Potential Marginally suitable coastal scrub habitat is present within the study area. The closest CNPS
record is from 1995 and is located approximately 4.6 miles northeast of the study area. This
species was not observed within the study area during April or June botanical surveys. This
species is not expected to occur on site.
Calochortus clavatus var. clavatus
club-haired mariposa-lily
None/None
G4T3/S3
4.3
Perennial bulbiferous herb. Chaparral, cismontane woodland, coastal scrub, valley and
foothill grassland. Clay, Rocky, serpentinite (usually). Elevations: 100-4265ft. (30-1300m.)
Blooms (Mar)May-Jun.
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area.
Several CNPS records are known from the vicinity of the study area, the nearest of which is
from 2023 and is located approximately 0.7-mile west of the study area. This species was not
observed within the study area during April or June botanical surveys. This species is not
expected to occur on site.
Calochortus obispoensis
San Luis mariposa-lily
None/None
G2/S2
1B.2
Perennial bulbiferous herb. Chaparral, cismontane woodland, coastal scrub, valley and
foothill grassland. Serpentinite (often). Elevations: 165-2395ft. (50-730m.) Blooms May-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Calochortus simulans
La Panza mariposa-lily
None/None
G2/S2
1B.3
Perennial bulbiferous herb. Chaparral, cismontane woodland, lower montane coniferous
forest, valley and foothill grassland. Granitic (often), sandy, serpentinite (sometimes).
Elevations: 1065-3775ft. (325-1150m.) Blooms Apr-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Calystegia subacaulis ssp.
episcopalis
Cambria morning-glory
None/None
G3T2?/S2?
4.2
Perennial rhizomatous herb. Chaparral, cismontane woodland, coastal prairie, valley and
foothill grassland. Clay (usually). Elevations: 100-1640ft. (30-500m.) Blooms (Mar)Apr-
Jun(Jul).
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area. The
closest CNDDB record is from 2003 and is located approximately 1.3 miles east of the study
area. This species was not observed within the study area during April or June botanical
surveys. This species is not expected to occur on site. .
Camissoniopsis hardhamiae
Hardham's evening-primrose
None/None
G2/S2
1B.2
Annual herb. Chaparral, cismontane woodland. Burned areas (sometimes), carbonate,
disturbed areas (sometimes), sandy. Elevations: 460-3100ft. (140-945m.) Blooms Mar-
May.
Does Not Occur The study area is located outside the known elevation range of this species.
Carex obispoensis
San Luis Obispo sedge
None/None
G3?/S3?
1B.2
Perennial cespitose herb. Chaparral, closed-cone coniferous forest, coastal prairie, coastal
scrub, valley and foothill grassland. Usually in transition zone on sand, clay, serpentine, or
gabbro. In seeps. Elevations: 35-2690ft. (10-820m.) Blooms Apr-Jun.
Low Potential Potentially suitable closed-cone coniferous forest, coastal scrub, and valley and foothill
grassland habitats are present within the study area. The closest CNDDB record is from 2011
and is located approximately 1.2 miles west of the study area. This species was not observed
within the study area during April or June botanical surveys. This species is not expected to
occur on site.
Castilleja densiflora var.
obispoensis
San Luis Obispo owl's-clover
None/None
G5T2/S2
1B.2
Annual herb (hemiparasitic). Meadows and seeps, valley and foothill grassland. Serpentinite
(sometimes). Elevations: 35-1410ft. (10-430m.) Blooms Mar-May.
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area.
Several CNDDB records are known from the vicinity of the study area, the nearest of which is
from 2008 and is located approximately 1.1 mile east of the study area. This species was not
observed within the study area during April or June botanical surveys. This species is not
expected to occur on site.
Ceanothus cuneatus var.
fascicularis
Lompoc ceanothus
None/None
G5T4/S4
4.2
Perennial evergreen shrub. Chaparral. Sandy soils. Elevations: 15-1310ft. (5-400m.)
Blooms Feb-Apr.
Does Not Occur No suitable habitat is present within the study area.
Ceanothus impressus var.
nipomensis
Nipomo Mesa ceanothus
None/None
G3T2/S2
1B.2
Perennial shrub. Chaparral. Sandy. Elevations: 100-805ft. (30-245m.) Blooms Feb-Apr. Does Not Occur No suitable habitat is present within the study area.
Ceanothus thyrsiflorus var.
obispoensis
San Luis Obispo ceanothus
None/None
G5T1/S1
1B.1
Perennial shrub. Chaparral, cismontane woodland. Dacite. Elevations: 460-740ft. (140-
225m.) Blooms Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Centromadia parryi ssp. congdonii
Congdon's tarplant
None/None
G3T2/S2
1B.1
Annual herb. Valley and foothill grassland. Alkaline soils, sometimes described as heavy
white clay. Elevations: 0-755ft. (0-230m.) Blooms May-Oct(Nov).
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area. The
closest CNDDB record is from 2002 and is located approximately 0.6 mile east of the study
area. This species was not observed within the study area during April or June botanical
surveys. This species is not expected to occur on site.
Cercocarpus betuloides var.
blancheae
island mountain-mahogany
None/None
G5T4/S4
4.3
Perennial evergreen shrub. Chaparral, closed-cone coniferous forest. Elevations: 100-
1970ft. (30-600m.) Blooms Feb-May.
Low Potential Marginally suitable closed-cone coniferous forest habitat is present within the study area. The
closest CNPS record is from 1975 and is located approximately 2.2 miles northwest of the
study area. This species was not observed within the study area during April or June botanical
surveys. This species is not expected to occur on site.
Page 276 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-3
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Chenopodium littoreum
coastal goosefoot
None/None
G1/S1
1B.2
Annual herb. Coastal dunes. Generally on sandy soils, and on dunes. Elevations: 35-100ft.
(10-30m.) Blooms Apr-Aug.
Does Not Occur No suitable habitat is present within the study area.
Chlorogalum pomeridianum var.
minus
dwarf soaproot
None/None
G5T3/S3
1B.2
Perennial bulbiferous herb. Chaparral. Serpentine. Elevations: 1000-3280ft. (305-1000m.)
Blooms May-Aug.
Does Not Occur The study area is located outside the known elevation range of this species.
Chloropyron maritimum ssp.
maritimum
salt marsh bird's-beak
FE/SE
G4?T1/S1
1B.2
Annual herb (hemiparasitic). Coastal dunes, marshes and swamps. Limited to the higher
zones of salt marsh habitat. Elevations: 0-100ft. (0-30m.) Blooms May-Oct(Nov).
Does Not Occur The study area is located outside the known elevation range of this species.
Chloropyron maritimum ssp.
palustre
Point Reyes salty bird's-beak
None/None
G4?T2/S2
1B.2
Annual herb (hemiparasitic). Marshes and swamps. Usually in coastal salt marsh with
Salicornia, Distichlis, Jaumea, Spartina, etc. Elevations: 0-35ft. (0-10m.) Blooms Jun-Oct.
Does Not Occur The study area is located outside the known elevation range of this species.
Chorizanthe aphanantha
Irish Hills spineflower
None/None
G1/S1
1B.1
Annual herb. Chaparral, coastal scrub. Gravelly, rocky, serpentinite. Elevations: 330-1215ft.
(100-370m.) Blooms Apr-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Chorizanthe breweri
Brewer's spineflower
None/None
G3/S3
1B.3
Annual herb. Chaparral, cismontane woodland, closed-cone coniferous forest, coastal scrub.
Gravelly (sometimes), rocky (sometimes), serpentinite. Elevations: 150-2625ft. (45-800m.)
Blooms Apr-Aug.
Does Not Occur The study area is located outside the known elevation range of this species.
Chorizanthe douglasii
Douglas' spineflower
None/None
G4/S4
4.3
Annual herb. Chaparral, cismontane woodland, coastal scrub, lower montane coniferous
forest, valley and foothill grassland. Gravelly (sometimes), sandy (sometimes). Elevations:
180-5250ft. (55-1600m.) Blooms Apr-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Chorizanthe palmeri
Palmer's spineflower
None/None
G4/S4
4.2
Annual herb. Chaparral, cismontane woodland, valley and foothill grassland. Rocky,
serpentinite. Elevations: 180-3100ft. (55-945m.) Blooms Apr-Aug.
Does Not Occur The study area is located outside the known elevation range of this species.
Chorizanthe rectispina
straight-awned spineflower
None/None
G2/S2
1B.2
Annual herb. Chaparral, cismontane woodland, coastal scrub. Often on granite in chaparral.
Elevations: 280-3395ft. (85-1035m.) Blooms Apr-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Chorizanthe ventricosa
potbellied spineflower
None/None
G3/S3
4.3
Annual herb. Cismontane woodland, valley and foothill grassland. Serpentinite. Elevations:
215-4050ft. (65-1235m.) Blooms May-Sep.
Does Not Occur The study area is located outside the known elevation range of this species.
Cirsium fontinale var. obispoense
Chorro Creek bog thistle
FE/SE
G2T2/S2
1B.2
Perennial herb. Chaparral, cismontane woodland, coastal scrub, valley and foothill
grassland. Drainages, seeps, serpentinite. Elevations: 115-1265ft. (35-385m.) Blooms Feb-
Jul(Aug-Sep).
Low Potential Potentially suitable coastal scrub, cismontane woodland, and valley and foothill grassland
habitats are present within the study area. The closest CNDDB record is from 2015 and is
located approximately 1.1 mile northeast of the study area. This species was not observed
within the study area during April or June botanical surveys. This species is not expected to
occur on site.
Cirsium occidentale var. lucianum
Cuesta Ridge thistle
None/None
G3G4T2/S2
1B.2
Perennial herb. Chaparral. Disturbed areas, roadsides, rocky (often), serpentinite, slopes
(often). Elevations: 1640-2460ft. (500-750m.) Blooms Apr-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Cirsium rhothophilum
surf thistle
None/ST
G1/S1
1B.2
Perennial herb. Coastal bluff scrub, coastal dunes. Open areas in central dune scrub;
usually in coastal dunes. Elevations: 10-195ft. (3-60m.) Blooms Apr-Jun.
Does Not Occur No suitable habitat is present within the study area.
Cirsium scariosum var. loncholepis
La Graciosa thistle
FE/ST
G5T1/S1
1B.1
Perennial herb. Cismontane woodland, coastal dunes, coastal scrub, marshes and swamps,
valley and foothill grassland. Mesic, sandy. Elevations: 15-720ft. (4-220m.) Blooms May-
Aug.
Does Not Occur The study area is located outside the known range of this species.
Cladium californicum
California saw-grass
None/None
G4/S2
2B.2
Perennial rhizomatous herb. Marshes and swamps, meadows and seeps. Freshwater or
alkaline moist habitats. Elevations: 195-5250ft. (60-1600m.) Blooms Jun-Sep.
Does Not Occur The study area is located outside the known elevation range of this species.
Cladonia firma
popcorn lichen
None/None
G4/S1
2B.1
Squamulose lichen (terricolous). Coastal dunes, coastal scrub. On soil and detritus on
stabilized sand dunes, in pure stands or intermixed with other lichens and mosses forming
biotic soil crusts, covering areas up to several meters. Elevations: 100-245ft. (30-75m.)
Does Not Occur No suitable habitat is present within the study area.
Page 277 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-4
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Clarkia speciosa ssp. immaculata
Pismo clarkia
FE/SR
G4T1/S1
1B.1
Annual herb. Chaparral, cismontane woodland, valley and foothill grassland. Sandy.
Elevations: 80-605ft. (25-185m.) Blooms May-Jul.
Low Potential Potentially suitable cismontane woodland and valley and foothill grassland habitats are present
within the study area. The closest CNDDB record is from 2015 and is located approximately 3.1
miles southeast of the study area. This species was not observed within the study area during
April or June botanical surveys. This species is not expected to occur on site.
Clinopodium mimuloides
monkey-flower savory
None/None
G3/S3
4.2
Perennial herb. Chaparral, north coast coniferous forest. Mesic, streambanks. Elevations:
1000-5905ft. (305-1800m.) Blooms Jun-Oct.
Does Not Occur The study area is located outside the known elevation range of this species.
Deinandra paniculata
paniculate tarplant
None/None
G4/S4
4.2
Annual herb. Coastal scrub, valley and foothill grassland, vernal pools. Usually in vernally
mesic sites. Sometimes in vernal pools or on mima mounds near them. Elevations: 80-
3085ft. (25-940m.) Blooms (Mar)Apr-Nov.
Low Potential Potentially suitable coastal scrub and valley and foothill grassland habitats are present within
the study area. The closest CNDDB record is from 1969 and is located approximately 3.8 miles
northwest of the study area. This species was not observed within the study area during April or
June botanical surveys. This species is not expected to occur on site.
Delphinium hutchinsoniae
Hutchinson's larkspur
None/None
G2/S2
1B.2
Perennial herb. Broadleafed upland forest, chaparral, coastal prairie, coastal scrub. On
semi-shaded, slightly moist slopes, usually west-facing. Elevations: 0-1400ft. (0-427m.)
Blooms Mar-Jun.
Does Not Occur The study area is located outside the known range of this species.
Delphinium parryi ssp. blochmaniae
dune larkspur
None/None
G4T2/S2
1B.2
Perennial herb. Chaparral, coastal dunes. On rocky areas and dunes. Elevations: 0-655ft.
(0-200m.) Blooms Apr-Jun.
Does Not Occur No suitable habitat is present within the study area.
Delphinium parryi ssp. eastwoodiae
Eastwood's larkspur
None/None
G4T2/S2
1B.2
Perennial herb. Chaparral, valley and foothill grassland. Serpentine. Openings. Elevations:
245-1640ft. (75-500m.) Blooms (Feb)Mar-Apr.
Does Not Occur The study area is located outside the known elevation range of this species.
Delphinium umbraculorum
umbrella larkspur
None/None
G3/S3
1B.3
Perennial herb. Chaparral, cismontane woodland. Mesic sites. Elevations: 1310-5250ft.
(400-1600m.) Blooms Apr-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Dithyrea maritima
beach spectaclepod
None/ST
G1/S1
1B.1
Perennial rhizomatous herb. Coastal dunes, coastal scrub. Sea shores, on sand dunes, and
sandy places near the shore. Elevations: 10-165ft. (3-50m.) Blooms Mar-May.
Does Not Occur No suitable habitat is present within the study area.
Dudleya abramsii ssp. bettinae
Betty's dudleya
None/None
G4T2/S2
1B.2
Perennial herb. Chaparral, coastal scrub, valley and foothill grassland. On rocky, barren
exposures of serpentine within scrub vegetation. Elevations: 65-590ft. (20-180m.) Blooms
May-Jul.
Low Potential Marginally suitable coastal scrub and valley and foothill grassland habitats are present within
the study area. The closest CNDDB record is from 2008 and is located approximately 1.6 mile
east of the study area. This species was not observed within the study area during April or June
botanical surveys. This species is not expected to occur on site.
Dudleya abramsii ssp. murina
mouse-gray dudleya
None/None
G4T2/S2
1B.1
Perennial leaf. Chaparral, cismontane woodland, valley and foothill grassland. Serpentine
outcrops. Elevations: 295-1725ft. (90-525m.) Blooms May-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Dudleya blochmaniae ssp.
blochmaniae
Blochman's dudleya
None/None
G3T2/S2
1B.1
Perennial herb. Chaparral, coastal bluff scrub, coastal scrub, valley and foothill grassland.
Open, rocky slopes; often in shallow clays over serpentine or in rocky areas with little soil.
Elevations: 15-1475ft. (5-450m.) Blooms Apr-Jun.
Low Potential Marginally suitable coastal scrub and valley and foothill grassland habitats are present within
the study area. The closest CNDDB record is from 1987 and is located approximately 0.75 mile
southwest of the study area. This species was not observed within the study area during April or
June botanical surveys. This species is not expected to occur on site.
Eleocharis parvula
small spikerush
None/None
G5/S3
4.3
Perennial herb. Marshes and swamps. In coastal salt marshes. Elevations: 5-9910ft. (1-
3020m.) Blooms (Apr)Jun-Aug(Sep).
Does Not Occur No suitable habitat is present within the study area.
Eriastrum luteum
yellow-flowered eriastrum
None/None
G2/S2
1B.2
Annual herb. Broadleafed upland forest, chaparral, cismontane woodland. On bare sandy
decomposed granite slopes. Elevations: 950-3280ft. (290-1000m.) Blooms May-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Erigeron blochmaniae
Blochman's leafy daisy
None/None
G2/S2
1B.2
Perennial rhizomatous herb. Coastal dunes, coastal scrub. Sand dunes and hills. Elevations:
10-150ft. (3-45m.) Blooms Jun-Aug.
Does Not Occur No suitable habitat is present within the study area.
Erigeron sanctarum
saints' daisy
None/None
G3/S3
4.2
Perennial rhizomatous herb. Chaparral, cismontane woodland, coastal scrub. Elevations:
245-1150ft. (75-350m.) Blooms Mar-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Page 278 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-5
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Eriodictyon altissimum
Indian Knob mountainbalm
FE/SE
G1/S1
1B.1
Perennial evergreen shrub. Chaparral, cismontane woodland, coastal scrub. Ridges in open,
disturbed areas within chaparral on Pismo sandstone. Elevations: 260-885ft. (80-270m.)
Blooms Mar-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Eryngium aristulatum var. hooveri
Hoover's button-celery
None/None
G5T1/S1
1B.1
Annual/perennial herb. Vernal pools. Alkaline depressions, vernal pools, roadside ditches
and other wet places near the coast. Elevations: 10-150ft. (3-45m.) Blooms (Jun)Jul(Aug).
Does Not Occur No suitable habitat is present within the study area.
Erysimum capitatum var.
lompocense
San Luis Obispo wallflower
None/None
G5T3/S3
4.2
Perennial herb. Chaparral, coastal scrub. Sandy hillsides and mesas. Elevations: 195-
1640ft. (60-500m.) Blooms Feb-May.
Does Not Occur The study area is located outside the known elevation range of this species.
Erysimum suffrutescens
suffrutescent wallflower
None/None
G3/S3
4.2
Perennial herb. Chaparral, coastal bluff scrub, coastal dunes, coastal scrub. Coastal dunes
and bluffs. Elevations: 0-490ft. (0-150m.) Blooms Jan-Jul(Aug).
Does Not Occur No suitable habitat is present within the study area.
Erythranthe serpentinicola
Irish Hills monkeyflower
None/None
G1/S1
1B.1
Annual herb. Chaparral (openings), meadows and seeps (edges). Serpentine, rocky,
openings, mesic. 60-360m. Blooms Feb-May.
Does Not Occur No suitable habitat is present within the study area.
Eschscholzia hypecoides
San Benito poppy
None/None
G4/S4
4.3
Annual herb. Chaparral, cismontane woodland, valley and foothill grassland. Serpentine
clay. Elevations: 655-4920ft. (200-1500m.) Blooms Mar-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Extriplex joaquinana
San Joaquin spearscale
None/None
G2/S2
1B.2
Annual herb. Chenopod scrub, meadows and seeps, playas, valley and foothill grassland. In
seasonal alkali wetlands or alkali sink scrub with Distichlis spicata, Frankenia, etc.
Elevations: 5-2740ft. (1-835m.) Blooms Apr-Oct.
Does Not Occur The study area is located outside the known range of this species.
Fritillaria agrestis
stinkbells
None/None
G3/S3
4.2
Perennial bulbiferous herb. Chaparral, cismontane woodland, pinyon and juniper woodland,
valley and foothill grassland. Sometimes on serpentine; mostly found in nonnative
grassland or in grassy openings in clay soil. Elevations: 35-5100ft. (10-1555m.) Blooms
Mar-Jun.
Low Potential Potentially suitable cismontane woodland and valley and foothill grassland habitats are present
within the study area. No CNDDB or CNPS records occur within 5 miles of the study area. This
species was not observed within the study area during April or June botanical surveys. This
species is not expected to occur on site.
Fritillaria ojaiensis
Ojai fritillary
None/None
G3/S3
1B.2
Perennial bulbiferous herb. Broadleafed upland forest, chaparral, cismontane woodland,
lower montane coniferous forest. Rocky sites. Sometimes on serpentine; sometimes along
roadsides. Elevations: 740-3275ft. (225-998m.) Blooms Feb-May.
Does Not Occur The study area is located outside the known elevation range of this species.
Galium cliftonsmithii
Santa Barbara bedstraw
None/None
G4/S4
4.3
Perennial herb. Cismontane woodland. Light shade, coastal canyons, dry banks. Elevations:
655-4005ft. (200-1220m.) Blooms May-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Gilia tenuiflora ssp. amplifaucalis
trumpet-throated gilia
None/None
G3G4T3/S3
4.3
Annual herb. Cismontane woodland, valley and foothill grassland. Sandy soils. Elevations:
1280-2955ft. (390-900m.) Blooms Mar-Apr.
Does Not Occur The study area is located outside the known elevation range of this species.
Grindelia hirsutula var. maritima
San Francisco gumplant
None/None
G5T1Q/S1
3.2
Perennial herb. Coastal bluff scrub, coastal scrub, valley and foothill grassland. Sandy or
serpentine slopes, sea bluffs. Elevations: 50-1310ft. (15-400m.) Blooms Jun-Sep.
Low Potential Marginally suitable coastal scrub and valley and foothill grassland habitats are present within
the study area. No CNDDB or CNPS records occur within 5 miles of the study area. This species
was not observed within the study area during April or June botanical surveys. This species is
not expected to occur on site.
Horkelia cuneata var. puberula
mesa horkelia
None/None
G4T1/S1
1B.1
Perennial herb. Chaparral, cismontane woodland, coastal scrub. Sandy or gravelly sites.
Elevations: 230-2660ft. (70-810m.) Blooms Feb-Jul(Sep).
Does Not Occur The study area is located outside the known elevation range of this species.
Horkelia cuneata var. sericea
Kellogg's horkelia
None/None
G4T1?/S1?
1B.1
Perennial herb. Chaparral, closed-cone coniferous forest, coastal dunes, coastal scrub. Old
dunes, coastal sandhills; openings. Sandy or gravelly soils. Elevations: 35-655ft. (10-200m.)
Blooms Apr-Sep.
Does Not Occur The study area is located outside the known range of this species.
Horkelia yadonii
Santa Lucia horkelia
None/None
G3/S3
4.2
Perennial rhizomatous herb. Broadleafed upland forest, chaparral, cismontane woodland,
meadows and seeps, riparian woodland. Sandy meadow edges, seasonal streambeds.
Granitic soils. Elevations: 985-6235ft. (300-1900m.) Blooms Apr-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Juncus acutus ssp. leopoldii
southwestern spiny rush
None/None
G5T5/S4
4.2
Perennial rhizomatous herb. Coastal dunes, marshes and swamps, meadows and seeps.
Moist saline places. Elevations: 10-2955ft. (3-900m.) Blooms (Mar)May-Jun.
Does Not Occur No suitable habitat is present within the study area.
Page 279 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-6
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Lasthenia californica ssp.
macrantha
perennial goldfields
None/None
G3T2/S2
1B.2
Perennial herb. Coastal bluff scrub, coastal dunes, coastal scrub. Elevations: 15-1705ft. (5-
520m.) Blooms Jan-Nov.
Does Not Occur The study area is located outside the known range of this species.
Lasthenia glabrata ssp. coulteri
Coulter's goldfields
None/None
G4T2/S2
1B.1
Annual herb. Marshes and swamps, playas, vernal pools. Usually found on alkaline soils in
playas, sinks, and grasslands. 1-. Elevations: 5-4005ft. (1-1220m.) Blooms Feb-Jun.
Does Not Occur The study area is located outside the known range of this species.
Lasthenia leptalea
Salinas Valley goldfields
None/None
G3/S3
4.3
Annual herb. Cismontane woodland, valley and foothill grassland. Elevations: 195-3495ft.
(60-1065m.) Blooms Feb-Apr.
Does Not Occur The study area is located outside the known elevation range of this species.
Layia erubescens
blushing layia
None/None
G2/S2
1B.2
Coastal dunes, coastal scrub. Prefers loose, fine sand of stabilized dunes and sandhills. 10-
245m. Blooms (Feb)Mar-May(Jun).
Does Not Occur No suitable habitat is present within the study area.
Layia jonesii
Jones' layia
None/None
G2/S2
1B.2
Annual herb. Chaparral, valley and foothill grassland. Clay soils and serpentine outcrops.
Elevations: 15-1310ft. (5-400m.) Blooms Mar-May.
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area. The
closest CNPS record is from 1988 and is located approximately 0.5 mile west of the study area.
This species was not observed within the study area during April or June botanical surveys.This
species is not expected to occur on site.
Leptosiphon grandiflorus
large-flowered leptosiphon
None/None
G3G4/S3S4
4.2
Annual herb. Cismontane woodland, closed-cone coniferous forest, coastal bluff scrub,
coastal dunes, coastal prairie, coastal scrub, valley and foothill grassland. Open, grassy
flats, generally sandy soil. 5-. Elevations: 15-4005ft. (5-1220m.) Blooms Apr-Aug.
Low Potential Potentially suitable closed-cone coniferous forest, cismontane woodland, coastal scrub, and
valley and foothill grassland habitats are present within the study area. The closest CNPS
record is from 1982 and is located approximately 1.6 miles northwest of the study area. This
species was not observed within the study area during April or June botanical surveys. This
species is not expected to occur on site.
Lessingia tenuis
spring lessingia
None/None
G4/S4
4.3
Annual herb. Chaparral, cismontane woodland, lower montane coniferous forest. Openings.
Elevations: 985-7055ft. (300-2150m.) Blooms May-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Linanthus californicus ssp.
tomentosus
fuzzy prickly-phlox
None/None
G5T3/S3
4.2
Perennial deciduous shrub. Coastal dunes. Elevations: 5-605ft. (1-185m.) Blooms Mar-Aug.Does Not Occur No suitable habitat is present within the study area.
Lomatium parvifolium
small-leaved lomatium
None/None
G3/S3
4.2
Perennial herb. Chaparral, closed-cone coniferous forest, coastal scrub, riparian woodland.
On serpentine. Elevations: 65-2295ft. (20-700m.) Blooms Jan-Jun.
Low Potential Marginally suitable closed-cone coniferous forest habitat is present within the study area. The
closest CNPS record is from 1988 and is located approximately 0.5 mile southwest of the study
area. This species was not observed within the study area during April or June botanical
surveys. This species is not expected to occur on site.
Lupinus ludovicianus
San Luis Obispo County lupine
None/None
G1/S1
1B.2
Perennial herb. Chaparral, cismontane woodland. Open areas in sandy soil, Santa Margarita
formation. Elevations: 165-1725ft. (50-525m.) Blooms Apr-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Lupinus nipomensis
Nipomo Mesa lupine
FE/SE
G1/S1
1B.1
Annual herb. Coastal dunes. Dry sandy flats, restricted to back dunes, associated with
central dune scrub habitat - a rare community type. Elevations: 35-165ft. (10-50m.) Blooms
Dec-May.
Does Not Occur No suitable habitat is present within the study area.
Malacothamnus gracilis
slender bush-mallow
None/None
G1Q/S1
1B.1
Perennial deciduous shrub. Chaparral. Dry, rocky slopes. Elevations: 625-1885ft. (190-
575m.) Blooms May-Oct.
Does Not Occur The study area is located outside the known elevation range of this species.
Malacothamnus jonesii
Jones' bush-mallow
None/None
G4/S4
4.3
Perennial deciduous shrub. Chaparral, cismontane woodland. Elevations: 525-3525ft. (160-
1075m.) Blooms (Mar)Apr-Oct.
Does Not Occur The study area is located outside the known elevation range of this species.
Malacothamnus palmeri var.
palmeri
Santa Lucia bush-mallow
None/None
G3T2Q/S2
1B.2
Perennial deciduous shrub. Chaparral. Dry rocky slopes, mostly near summits, but
occasionally extending down canyons to the sea. Elevations: 195-1180ft. (60-360m.)
Blooms May-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Malacothrix incana
dunedelion
None/None
G3G4/S3S4
4.3
Perennial herb. Coastal dunes, coastal scrub. On flats and slopes, as well as unstabilized
dunes near the ocean. Elevations: 5-115ft. (2-35m.) Blooms (Jan)Apr-Oct.
Does Not Occur The study area is located outside the known range of this species.
Page 280 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-7
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Mielichhoferia elongata
elongate copper moss
None/None
G5/S3S4
4.3
Moss. Broadleafed upland forest, chaparral, cismontane woodland, coastal scrub, lower
montane coniferous forest, meadows and seeps, subalpine coniferous forest. Moss growing
on very acidic, metamorphic rock or substrate; usually in higher portions in fens. Often on
substrates naturally enriched with heavy metals (e.g. copper) such as mine tailings. 5-.
Elevations: 0-6430ft. (0-1960m.)
Does Not Occur The study area is located outside the known range of this species.
Monardella palmeri
Palmer's monardella
None/None
G2/S2
1B.2
Perennial rhizomatous herb. Chaparral, cismontane woodland. On serpentine, often found
associated with Sargent cypress forests. Elevations: 655-2625ft. (200-800m.) Blooms Jun-
Aug.
Does Not Occur The study area is located outside the known elevation range of this species.
Monardella sinuata ssp. sinuata
southern curly-leaved monardella
None/None
G3T2/S2
1B.2
Annual herb. Chaparral, cismontane woodland, coastal dunes, coastal scrub. Sandy soils.
Elevations: 0-985ft. (0-300m.) Blooms Apr-Sep.
Does Not Occur No suitable habitat is present within the study area.
Monardella undulata ssp. crispa
crisp monardella
None/None
G3T2/S2
1B.2
Perennial rhizomatous herb. Coastal dunes, coastal scrub. Often on the borders of open,
sand areas, usually adjacent to typical backdune scrub vegetation. Elevations: 35-395ft.
(10-120m.) Blooms Apr-Aug(Dec).
Does Not Occur No suitable habitat is present within the study area.
Monardella undulata ssp. undulata
San Luis Obispo monardella
None/None
G2/S2
1B.2
Perennial rhizomatous herb. Coastal dunes, coastal scrub. Stabilized sand of the immediate
coast. Elevations: 35-655ft. (10-200m.) Blooms May-Sep.
Does Not Occur No suitable habitat is present within the study area.
Monolopia gracilens
woodland woollythreads
None/None
G3/S3
1B.2
Annual herb. Broadleafed upland forest, chaparral, cismontane woodland, north coast
coniferous forest, valley and foothill grassland. Grassy sites, in openings; sandy to rocky
soils. Often seen on serpentine after burns, but may have only weak affinity to serpentine.
Elevations: 330-3935ft. (100-1200m.) Blooms (Feb)Mar-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Mucronea californica
California spineflower
None/None
G3/S3
4.2
Annual herb. Chaparral, cismontane woodland, coastal dunes, coastal scrub, valley and
foothill grassland. Sandy soil. Elevations: 0-4595ft. (0-1400m.) Blooms Mar-Jul(Aug).
Low Potential Potentially suitable cismontane woodland, coastal scrub, and valley and foothill grassland
habitats are present within the study area. The closest CNPS record is from 1885 and is
located approximately 1.6 miles northwest of the study area. This species was not observed
within the study area during April or June botanical surveys. This species is not expected to
occur on site.
Muhlenbergia utilis
aparejo grass
None/None
G4/S2S3
2B.2
Perennial rhizomatous herb. Chaparral, cismontane woodland, coastal scrub, marshes and
swamps, meadows and seeps. Alkaline (sometimes), Serpentinite (sometimes).Elevations:
80-7630ft. (25-2325m.) Blooms Mar-Oct.
Low Potential Marginally suitable coastal scrub, cismontane woodland, and valley and foothill grassland
habitat is present within the study area. The closest CNPS record is from 2021 and is located
approximately 2.2 miles west of the study area. This species was not observed within the study
area during April or June botanical surveys. This species is not expected to occur on site.
Nasturtium gambelii
Gambel's water cress
FE/ST
G1/S1
1B.1
Perennial rhizomatous herb. Marshes and swamps. Freshwater and brackish marshes at
the margins of lakes and along streams, in or just above the water level. Elevations: 15-
1085ft. (5-330m.) Blooms Apr-Oct.
Does Not Occur The study area is located outside the known range of this species.
Navarretia nigelliformis ssp.
radians
shining navarretia
None/None
G4T2/S2
1B.2
Annual herb. Cismontane woodland, valley and foothill grassland, vernal pools. Apparently
in grassland, and not necessarily in vernal pools. Elevations: 215-3280ft. (65-1000m.)
Blooms (Mar)Apr-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Nemacaulis denudata var.
denudata
coast woolly-heads
None/None
G3G4T2/S2
1B.2
Annual herb. Coastal dunes. Elevations: 0-330ft. (0-100m.) Blooms Apr-Sep.Does Not Occur No suitable habitat is present within the study area.
Perideridia pringlei
adobe yampah
None/None
G4/S4
4.3
Perennial herb. Chaparral, cismontane woodland, coastal scrub, pinyon and juniper
woodland. Serpentine, clay soils. Grassland hillsides; seasonally wet sites. Elevations: 985-
5905ft. (300-1800m.) Blooms Apr-Jun(Jul).
Does Not Occur The study area is located outside the known elevation range of this species.
Piperia michaelii
Michael's rein orchid
None/None
G3/S3
4.2
Perennial herb. Chaparral, cismontane woodland, closed-cone coniferous forest, coastal
bluff scrub, coastal scrub, lower montane coniferous forest. Mudstone and humus,
generally dry sites. Elevations: 10-3000ft. (3-915m.) Blooms Apr-Aug.
Low Potential Marginally suitable cismontane woodland, closed-cone coniferous forest, and coastal scrub
habitats are present within the study area. The closest CNPS record is from 1886 and is
located approximately 2.5 miles northeast of the study area. This species was not observed
within the study area during April or June botanical surveys. This species is not expected to
occur on site.
Plagiobothrys uncinatus
hooked popcornflower
None/None
G2/S2
1B.2
Annual herb. Chaparral, cismontane woodland, valley and foothill grassland. Sandstone
outcrops and canyon sides; often in burned or disturbed areas. Elevations: 985-2495ft.
(300-760m.) Blooms Apr-May.
Does Not Occur The study area is located outside the known elevation range of this species.
Page 281 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-8
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Poa diaboli
Diablo Canyon blue grass
None/None
G2/S2
1B.2
Perennial rhizomatous herb. Chaparral, cismontane woodland, closed-cone coniferous
forest, coastal scrub. Shale, sometimes burned areas. Elevations: 395-1310ft. (120-400m.)
Blooms Mar-Apr.
Does Not Occur The study area is located outside the known elevation range of this species.
Prunus fasciculata var. punctata
sand almond
None/None
G5T4/S4
4.3
Perennial deciduous shrub. Chaparral, cismontane woodland, coastal dunes, coastal scrub.
Sandy flats. Elevations: 50-655ft. (15-200m.) Blooms Mar-Apr.
Does Not Occur The study area is located outside the known range of this species.
Ribes sericeum
Santa Lucia gooseberry
None/None
G4/S4
4.3
Perennial deciduous shrub. Broadleafed upland forest, cismontane woodland, coastal bluff
scrub, north coast coniferous forest. Along streams in redwood forests and on the coastal
slopes of the Santa Lucia Mtns. Elevations: 1000-4005ft. (305-1220m.) Blooms Feb-Apr.
Does Not Occur The study area is located outside the known elevation range of this species.
Sanicula hoffmannii
Hoffmann's sanicle
None/None
G3/S3
4.3
Perennial herb. Broadleafed upland forest, chaparral, cismontane woodland, coastal bluff
scrub, coastal scrub, lower montane coniferous forest. Cool slopes in deep soil, often in
moist shaded serpentine soils, or in clay soils. Elevations: 100-985ft. (30-300m.) Blooms
Mar-May.
Low Potential Marginally suitable cismontane woodland and coastal scrub habitats are present within the
study area. The closest CNPS record is from 2015 and is located approximately 0.6 mile
southwest of the study area. This species was not observed within the study area during April or
June botanical surveys. This species is not expected to occur on site.
Sanicula maritima
adobe sanicle
None/SR
G2/S2
1B.1
Perennial herb. Chaparral, coastal prairie, meadows and seeps, valley and foothill
grassland. Moist clay or ultramafic soils. Elevations: 100-785ft. (30-240m.) Blooms Feb-
May.
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area. The
closest CNPS record is from 2016 and is located approximately 1 mile northeast of the study
area. This species was not observed within the study area during April or June botanical
surveys. This species is not expected to occur on site.
Scrophularia atrata
black-flowered figwort
None/None
G2?/S2?
1B.2
Perennial herb. Chaparral, closed-cone coniferous forest, coastal dunes, coastal scrub,
riparian scrub. Sand, diatomaceous shales, and soils derived from other parent material;
around swales and in sand dunes. Elevations: 35-1640ft. (10-500m.) Blooms Mar-Jul.
Low Potential Marginally suitable closed-cone coniferous forest and coastal scrub habitats are present within
the study area. The closest CNDDB record is from 2012 and is located approximately 3.5 miles
southeast of the study area. This species was not observed within the study area during April or
June botanical surveys. This species is not expected to occur on site.
Senecio aphanactis
chaparral ragwort
None/None
G3/S2
2B.2
Annual herb. Chaparral, cismontane woodland, coastal scrub. Drying alkaline flats.
Elevations: 50-2625ft. (15-800m.) Blooms Jan-Apr(May).
Low Potential Marginally suitable cismontane woodland and coastal scrub habitats are present within the
study area. The closest CNDDB record is from 1927 and is located approximately 1.1 miles
northeast of the study area. This species was not observed within the study area during April or
June botanical surveys. This species is not expected to occur on site.
Senecio astephanus
San Gabriel ragwort
None/None
G3/S3
4.3
Perennial herb. Chaparral, coastal bluff scrub. Rocky slopes. Elevations: 1310-4920ft. (400-
1500m.) Blooms May-Jul.
Does Not Occur The study area is located outside the known elevation range of this species.
Senecio blochmaniae
Blochman's ragwort
None/None
G3/S3
4.2
Perennial herb. Coastal dunes. Elevations: 0-330ft. (0-100m.) Blooms May-Oct. Does Not Occur No suitable habitat is present within the study area.
Sidalcea hickmanii ssp. anomala
Cuesta Pass checkerbloom
None/SR
G3T1/S1
1B.2
Perennial herb. Chaparral, closed-cone coniferous forest. Rocky serpentine soil; associated
with Sargent cypress forest. Elevations: 1970-2625ft. (600-800m.) Blooms May-Jun.
Does Not Occur The study area is located outside the known elevation range of this species.
Streptanthus albidus ssp.
peramoenus
most beautiful jewelflower
None/None
G2T2/S2
1B.2
Annual herb. Chaparral, cismontane woodland, valley and foothill grassland. Serpentine
outcrops, on ridges and slopes. Elevations: 310-3280ft. (95-1000m.) Blooms (Mar)Apr-
Sep(Oct).
Does Not Occur The study area is located outside the known elevation range of this species.
Suaeda californica
California seablite
FE/None
G1/S1
1B.1
Perennial evergreen shrub. Marshes and swamps. Margins of coastal salt marshes.
Elevations: 0-50ft. (0-15m.) Blooms Jul-Oct.
Does Not Occur The study area is located outside the known elevation range of this species.
Sulcaria isidiifera
splitting yarn lichen
None/None
G1/S1
1B.1
Fruticose lichen (epiphytic). Coastal scrub. On branches of oaks and shrubs in old growth
coastal scrub. Elevations: 65-100ft. (20-30m.)
Does Not Occur No suitable habitat is present within the study area.
Sulcaria spiralifera
twisted horsehair lichen
None/None
G3G4/S2
1B.2
Fruticose lichen (epiphytic). Coastal dunes, north coast coniferous forest. Usually on
conifers. Elevations: 0-295ft. (0-90m.)
Does Not Occur No suitable habitat is present within the study area.
Symphyotrichum defoliatum
San Bernardino aster
None/None
G2/S2
1B.2
Perennial rhizomatous herb. Cismontane woodland, coastal scrub, lower montane
coniferous forest, marshes and swamps, meadows and seeps, valley and foothill grassland.
Vernally mesic grassland or near ditches, streams and springs; disturbed areas. Elevations:
5-6695ft. (2-2040m.) Blooms Jul-Nov.
Does Not Occur The study area is located outside the known range of this species.
Page 282 of 717
City of San Luis Obispo
PCE Plume Characterization Project
1-9
Scientific Name
Common Name Status Habitat Requirements
Potential to Occur in
Project Site Habitat Suitability/Observations
Trifolium hydrophilum
saline clover
None/None
G2/S2
1B.2
Annual herb. Marshes and swamps, valley and foothill grassland, vernal pools. Mesic,
alkaline sites. Elevations: 0-985ft. (0-300m.) Blooms Apr-Jun.
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area. The
closest CNDDB record is from 1998 and is located approximately 1.1 miles northwest of the
study area. This species was not observed within the study area during April or June botanical
surveys. This species is not expected to occur on site.
Tropidocarpum capparideum
caper-fruited tropidocarpum
None/None
G1/S1
1B.1
Annual herb. Valley and foothill grassland. Alkaline clay. Elevations: 5-1495ft. (1-455m.)
Blooms Mar-Apr.
Low Potential Potentially suitable valley and foothill grassland habitat is present within the study area. No
CNDDB or CNPS records occur within 5 miles of the study area. This species was not observed
within the study area during April or June botanical surveys. This species is not expected to
occur on site.
Status (Federal/State)
FE = Federal Endangered
FT = Federal Threatened
SE = State Endangered
ST = State Threatened
SR = State Rare
CRPR (California Native Plant Society California Rare Plant Rank)
1B = Rare, Threatened, or Endangered in California and elsewhere
2B= Rare, Threatened, or Endangered in California, but more common elsewhere
CRPR Threat Code Extension
.1 = Seriously endangered in California (>80% of occurrences threatened/high degree and immediacy of threat)
.2 = Moderately threatened in California (20-80% of occurrences threatened/moderate degree and immediacy of threat)
.3 = Not very endangered in California (<20% of occurrences threatened/low degree and immediacy of threat)
Other Statuses
G1 or S1 Critically Imperiled Globally or Subnationally (state)
G2 or S2 Imperiled Globally or Subnationally (state)
G3 or S3 Vulnerable to extirpation or extinction Globally or Subnationally (state)
G4/5 or S4/5Apparently secure, common and abundant
Additional notations may be provided as follows
T – Intraspecific Taxon (subspecies, varieties, and other designations below the level of species)
Q – Questionable taxonomy that may reduce conservation priority
? – Inexact numeric rank
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Attachment 2
Floral Compendium
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City of San Luis Obispo
PCE Plume Characterization Project
2-1
Common Name1 Scientific Name Native/Non-native Status
Wattle Acacia sp. Non-native --
Box elder Acer negundo Native --
American bird’s foot trefoil Acmispon americanus Native --
Buckeye Aesculus californica Native --
Ragweed Ambrosia psilostachya Native --
Narrow leaf milkweed Asclepias fascicularis Native --
Slender oat Avena barbata Non-native; Cal-IPC moderate --
Wild oat Avena fatua Non-native; Cal-IPC moderate --
Coyote brush Baccharis pilularis Native
Black mustard Brassica nigra Non-native; Cal-IPC moderate --
Rescue grass Bromus catharticus Non-native --
Ripgut brome Bromus diandrus Non-native; Cal-IPC moderate --
Soft brome Bromus hordeaceus Non-native; Cal-IPC limited --
California brome Bromus stichensis var. carinatus Native --
Incense cedar Calocedrus decurrens Native --
Italian thistle Carduus pycnocephalus Non-native; Cal-IPC moderate --
Yellow star thistle Centaurea solstitialis Non-native; Cal-IPC high --
Bull thistle Cirsium vulgare Non-native; Cal-IPC moderate --
Poison hemlock Conium maculatum Non-native; Cal-IPC moderate --
Field bindweed Convulvulus arvensis Non-native --
Bermuda grass Cynodon dactylon Non-native; Cal-IPC moderate --
Tall flatsedge Cyperus eragrostis Native --
Creeping wildrye Elymus triticoides Native --
Perennial veldt grass Ehrharta calycina Non-native; Cal-IPC high --
Canada horseweed Erigeron canadensis Native --
Coastal heron’s bill Erodium cicutarium Non-native; Cal-IPC limited --
California poppy Eschscholzia californica Native --
Fringed willowherb Epilobium ciliatum Native --
Blue gum Eucalyptus globulus Non-native; Cal-IPC limited --
Petty spurge Euphorbia peplus Non-native --
Italian rye grass Festuca perennis Non-native; Cal-IPC moderate --
Sweet fennel Foeniculum vulgare Non-native; Cal-IPC moderate --
Coffeeberry Frangula californica Native --
White ramping fumitory Fumaria capreolata Non-native --
Common bedstraw Galium aparine Native --
French broom Genista monspessulana Non-native; Cal-IPC high --
Cutleaf geranum Geranium dissectum Non-native; Cal-IPC limited --
Bristly ox-tongue Helminthotheca echioides Non-native; Cal-IPC limited --
Monterey cypress Hesperocyparis macrocarpa Native 1B.23
Toyon Heteromeles arbutifolia Native --
Foxtail barley Hordeum murinum Non-native; Cal-IPC moderate --
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City of San Luis Obispo
PCE Plume Characterization Project
2-2
Common Name1 Scientific Name Native/Non-native Status
Common barley Hordeum vulgare Non-native --
Northern California black
walnut
Juglans hindsii Native --
Prickly lettuce Lactuca serriola Non-native --
Glossy privet Ligustrum lucidum Non-native; Cal-IPC limited --
Santa Cruz Island ironwood Lyonothamnus floribundus ssp.
aspleniifolius
Native 1B.23
Cheeseweed mallow Malva parviflora Non-native --
Bur clover Medicago polymorpha Non-native; Cal-IPC limited --
Annual yellow sweetclover Melilotus indicus Non-native --
California wax myrtle Morella californica Native --
Mexican evening primrose Oenothera speciosa Non-native --
Olive Olea europaea Non-native; Cal-IPC limited --
Kikuyu grass Pennisetum clanedestinum Non-native; Cal-IPC limited --
Avocado Persea americana Non-native --
Harding grass Phalaris aquatica Non-native; Cal-IPC moderate --
Monterey pine Pinus radiata Native --
English plantain Plantago lanceolata Non-native; Cal-IPC limited --
Prostrate knotweed Polygonum aviculare Non-native --
Rabbitsfoot grass Polypogon monspeliensis Non-native; Cal-IPC limited --
Fremont cottonwood Populus fremontii Native --
Apricot Prunus armeniaca Non-native --
Jersey cudweed Pseudognaphalium luteoalbum Non-native --
Wild radish Raphanus sativus Non-native; Cal-IPC limited --
Coast live oak Quercus agrifolia Native --
Valley oak Quercus lobata Native --
Wild radish Raphanus sativus Non-native; Cal-IPC limited --
Lemonade berry Rhus integrifolia Native --
Castor bean Ricinus communis Non-native; Cal-IPC limited --
California rose Rosa californica Native --
Himalayan blackberry Rubus armeniacus Non-native; Cal-IPC high --
California blackberry Rubus ursinus Native --
Curly dock Rumex crispus Non-native; Cal-IPC limited --
Red willow Salix laevigata Native --
Arroyo willow Salix lasiolepis Native --
Blue elderberry Sambucas nexicana Native --
Peruvian pepper tree Schinus molle Non-native; Cal-IPC limited --
Coast redwood Sequoia sempervirens Native --
Milk thistle Silybum marianum Non-native; Cal-IPC limited --
Common nightshade Solanum americanum Native --
Spiny sowthistle Sonchus asper Non-native --
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City of San Luis Obispo
PCE Plume Characterization Project
2-3
Common Name1 Scientific Name Native/Non-native Status
Smilo grass Stipa miliacea Non-native --
Purple needlegrass Stipa pulchra Native --
Purple salsify Tragopogon porrifolius Non-native --
Rose clover Trifolium hirtum Non-native; Cal-IPC limited --
Common wheat Triticum aestivum Non-native --
Garden nasturtium Tropaeolum majus Non-native --
Spring vetch Vicia sativa Non-native --
Mexican fan palm Washingtonia robusta Non-native; Cal-IPC moderate --
Cal-IPC = California Invasive Plant Council
1Calflora 2024
2California Invasive Plant Council 2006. California Invasive Plant Inventory. Cal-IPC Publication 2006-02. California Invasive Plant
Council: Berkeley, CA. www.cal-ipc.org. Accessed June 2024.
3Not naturally occurring within the study area (i.e., ornamentally planted stands); as such, these individuals are not considered special-
status.
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Attachment 3
Site Photographs
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City of San Luis Obispo
PCE Plume Characterization Project
3-1
Photograph 1. View of the study area east of Highway 101, facing west. Taken April 26, 2024.
Photograph 2. View of the study area east of Highway 101, facing northeast. Taken April 26, 2024.
Page 289 of 717
City of San Luis Obispo
PCE Plume Characterization Project
3-2
Photograph 3. View of the study area east of Highway 101, facing northeast. Taken April 26, 2024.
Photograph 4. View of the study area east of Highway 101, facing northwest. Taken April 26, 2024.
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City of San Luis Obispo
PCE Plume Characterization Project
3-3
Photograph 5. View of the study area east of Highway 101, facing east. Taken April 26, 2024.
Photograph 6. View of the study area east of Highway 101, facing north. Taken April 26, 2024.
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City of San Luis Obispo
PCE Plume Characterization Project
3-4
Photograph 7. View of the study area west of Highway 101, facing northeast. Taken April 26, 2024.
Photograph 8. View of the study area east of Highway 101, facing northeast. Taken June 5, 2024.
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City of San Luis Obispo
PCE Plume Characterization Project
3-5
Photograph 9. View of the study area east of Highway 101, facing south. Taken June 5, 2024.
Photograph 10. View of the study area east of Highway 101, facing southwest. Taken June 5, 2024.
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Appendix C
Noise and Vibration Calculations
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Roadway Construction Noise Model (RCNM),Version 1.1
Report date:8/13/2024
Case Description:Treatment Wells
---- Receptor #1 ----
Baselines (dBA)
DescriptionLand Use Daytime Evening Night
ResidencesResidential 65 60 55
Equipment
Spec Actual Receptor Estimated
Impact Lmax Lmax Distance Shielding
Description Device Usage(%)(dBA)(dBA)(feet)(dBA)
Backhoe No 40 80 245 0
Concrete Pump Truck No 20 82 245 0
Crane No 16 85 245 0
Rock Drill No 20 85 245 0
Results
Calculated (dBA)Noise Limits (dBA)
Day Evening Night
Equipment *Lmax Leq Lmax Leq Lmax Leq Lmax
Backhoe 66.2 62.2 N/A N/A N/A N/A N/A
Concrete Pump Truck 68.2 61.2 N/A N/A N/A N/A N/A
Crane 71.2 63.2 N/A N/A N/A N/A N/A
Rock Drill 71.2 64.2 N/A N/A N/A N/A N/A
Total 71.2 68.9 N/A N/A N/A N/A N/A
*Calculated Lmax is the Loudest value.
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Noise Limit Exceedance (dBA)
Day Evening Night
Leq Lmax Leq Lmax Leq Lmax Leq
N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A
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Roadway Construction Noise Model (RCNM),Version 1.1
Report date:8/13/2024
Case Description:
---- Receptor #1 ----
Baselines (dBA)
DescriptionLand Use Daytime Evening Night
Residence Residential 65 60 55
Equipment
Spec Actual Receptor Estimated
Impact Lmax Lmax Distance Shielding
Description Device Usage(%)(dBA)(dBA)(feet)(dBA)
Backhoe No 40 80 150 0
Concrete Pump Truck No 20 82 150 0
Crane No 16 85 150 0
Rock Drill No 20 85 150 0
Results
Calculated (dBA)Noise Limits (dBA)
Day Evening Night
Equipment *Lmax Leq Lmax Leq Lmax Leq Lmax
Backhoe 70.5 66.5 N/A N/A N/A N/A N/A
Concrete Pump Truck 72.5 65.5 N/A N/A N/A N/A N/A
Crane 75.5 67.5 N/A N/A N/A N/A N/A
Rock Drill 75.5 68.5 N/A N/A N/A N/A N/A
Total 75.5 73.1 N/A N/A N/A N/A N/A
*Calculated Lmax is the Loudest value.
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Noise Limit Exceedance (dBA)
Day Evening Night
Leq Lmax Leq Lmax Leq Lmax Leq
N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A
N/A N/A N/A N/A N/A N/A N/A
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MTSJ-02 Vibration @ 25 ft Residential Area (15 feet) Residential Area (45 feet)
Phase 1 15 45
Cassion Drilling 0.089 0.191 0.037
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Page 300 of 717
Appendix D
Draft IS-MND Comment Letters
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State of California – The Natural Resources Agency GAVIN NEWSOM, Governor
DEPARTMENT OF FISH AND WILDLIFE CHARLTON H. BONHAM, Director
Central Region
1234 East Shaw Avenue
Fresno, California 93710
(559) 243-4005
www.wildlife.ca.gov
Conserving California’s Wildlife Since 1870
January 9, 2025
Shawna Scott, Special Projects Manager
City of San Luis Obispo
Public Utilities Department
879 Morro Street
San Luis Obispo, California 93401-3218
SScott@slocity.org
Subject: Groundwater Contamination Characterization Project (Project)
Mitigated Negative Declaration (MND)
SCH Number: 2024120528
Dear Shawna Scott:
The California Department of Fish and Wildlife (CDFW) received a Notice of Intent to
Adopt an Initial Study (IS)/MND from the City of San Luis Obispo for the Project
pursuant to the California Environmental Quality Act (CEQA) and CEQA Guidelines.1
Thank you for the opportunity to provide recommendations regarding th e activities
proposed at the Project site that may affect California fish and wildlife. Likewise, CDFW
appreciates the opportunity to provide comments regarding those aspects of the Project
that CDFW, by law, may be required to carry out or approve through the exercise of its
own regulatory authority under Fish and Game Code.
CDFW ROLE
CDFW is California’s Trustee Agency for fish and wildlife resources and holds those
resources in trust by statue for all the people of the State (Fish and Game Code,
§§ 711.7, subd. (a) & 1802; Pub. Resources Code, § 21070; CEQA Guidelines § 15386,
subd. (a)). CDFW, in its trustee capacity, has jurisdiction over the conservation,
protection, and management of fish, wildlife, native plants, and habitat necessary for
biologically sustainable populations of those species (Id., § 1802). Similarly, for
purposes of CEQA, CDFW is charged by law to provide, as available, biological
1 CEQA is codified in the California Public Resources Code in section 21000 et seq. The “CEQA
Guidelines” are found in Title 14 of the California Code of Regulations, commencing with section 15000.
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January 9, 2025
Page 2
expertise during public agency environmental review efforts, focusing specifically on
projects and related activities that have the potential to adversely affect fish and wildlife
resources.
CDFW is also submitting comments as a Responsible Agency under CEQA (Pub.
Resources Code, § 21069; CEQA Guidelines, § 15381). CDFW may need to exercise
regulatory authority as provided by the Fish and Game Code. For example, the Project
may be subject to CDFW’s lake and streambed alteration regulatory authority (Fish & G.
Code, § 1600 et seq.). Likewise, to the extent implementation of the Project as
proposed may result in “take” as defined by State law of any species protected under
the California Endangered Species Act (CESA) (Fish & Game Code, § 2050 et seq.),
related authorized as provided by the Fish and Game Code will be required.
In this role, CDFW is responsible for providing, as available, biological expertise during
public agency environmental review efforts (e.g., CEQA), focusing specifically on proje ct
activities that have the potential to adversely affect fish and wildlife resources. CDFW
provides recommendations to identify potential impacts and possible measures to avoid
or reduce those impacts.
Bird Protection: CDFW has jurisdiction over actions with potential to result in the
disturbance or destruction of active nest sites or the unauthorized take of birds. Fish
and Game Code sections that protect birds, their eggs and nests include sections 3503
(regarding unlawful take, possession or needless destruction of the nest or eggs of any
bird), 3503.5 (regarding the take, possession or destruction of any birds -of-prey or their
nests or eggs), and 3513 (regarding unlawful take of any migratory nongame bird).
Federally Listed Species: CDFW recommends consulting with the National Marine
Fisheries Service (NMFS) on potential impacts to anadromous Federally listed species.
Take under the Federal Endangered Species Act (ESA) is more broadly defined than
CESA; take under ESA also includes significant habitat modification or degradation that
could result in death or injury to a listed species by interfering with essential behavioral
patterns such as breeding, foraging, or nesting. Consultation with the NMFS to comply
with ESA is advised well in advance of any ground disturbing activities.
PROJECT DESCRIPTION SUMMARY
Proponent: City of San Luis Obispo (City)
Objective and Project Description: The City of San Luis Obispo is proposing to
construct monitoring and treatment wells to clean-up and prevent tetrachloroethylene
(PCE) contamination in drinking water supply wells. A maximum of 12 monitoring wells
will be constructed on developed locations that are paved and have exiting
infrastructure and be approximately 60 to 160 feet deep with a maximum depth of 200
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January 9, 2025
Page 3
feet. Two groundwater extraction and treatment wells with associated water conveyance
pipeline and infrastructure will be constructed on a 22-acre undeveloped site. One
treatment well (TW -3) was constructed in February 2003 but has since been capped.
Construction of the treatment wells and associated infrastructure includes the following:
Constructing a 650 square foot building at TW-3 site, to secure the well and
electrical panels, and to serve as the centralized treatment system for both wells.
Installing new treatment well TW -4, to a depth of 205 feet below ground surface.
Constructing a 250 square foot building at TW-4 site, to secure the well and
electrical panels.
Installing a new 6-inch sewer line to connect the backwash storage tank to the
City’s sanitary sewer system.
Installing a new 12-inch water line connecting the treatment infrastructure to the
City’s water distribution system.
Installing a new 8-inch water line connecting TW-4 to TW-3.
Installing perimeter security fencing, utility infrastructure, and access roads at
both sites.
Location: The Project is located within the City of San Luis Obispo, in the southern
portion of the City along U.S. Highway 101 between Prado Road and Los Osos Valley
Road, in San Luis Obispo County, within Assessor’s Parcel Number (APN) 053-051-
045, 053-052-045, 053-131-013, 053-141-012, 053-152-006, 053-152-008, 053-153-
014, and 053-153-008. The centroid for the treatment well location is approximately
35.24845 °N, -120.67869 °W.
Timeframe: Approximately beginning April of 2025 through October 2025.
COMMENTS AND RECOMMENDATIONS
CDFW offers the following recommendations to assist the City in adequately identifying
and/or mitigating the Project’s significant, or potentially significant, direct, indirect, and
cumulative impacts on fish and wildlife resources. Editorial comments or other
suggestions may also be included to improve the document.
Currently, the IS/MND acknowledges that the Project site is within the geographic range
of several special-status animal species and proposes general mitigation measures to
reduce impacts to less than significant; however, CDFW has concerns about the ability
of some proposed mitigation measures to reduce impacts to less than significant and to
avoid unauthorized take for special-status species including, but not limited to, the State
Candidate western burrowing owl (Athene cunicularia hypugaea) and Crotch’s bumble
bee (Bombus crotchii), and the State species of special concern and federally
threatened South-Central California Coast steelhead (S-CCC steelhead)
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Page 4
(Oncorhynchus mykiss irideus pop. 9). In addition, CDFW has concerns regarding
potential Project related impacts to water and riparian resources, including
interconnected surface waters and groundwater dependent ecosystems.
CDFW recommends that the following modifications and/or edits be incorporated into
the IS/MND, including proposed avoidance and minimization measures, prior to its
adoption by the City.
Western Burrowing Owl (BUOW)
The California Fish and Game Commission approved western burrowing owl (BUOW)
as a candidate for potential listing as a protected species under CESA on October 10,
2024, and published these findings in the California Regulatory Notice Register on
October 25, 2024. As such, BUOW is now a candidate under CESA and receives the
same legal protection afforded to an endangered or threatened species (Fish & G.
Code, §§ 2074.2 & 2085).
The Project is within known geographic range of BUOW (CDFW 2024) and the IS/MND
indicates that the proposed treatment well area contains suitable habitat for the species,
however, the IS/MND does not include a description of potential impacts to this species.
The IS/MND includes mitigation measures for general special-status species surveys
(BIO-2) and general nesting bird surveys (BIO-3), however, BUOW specific mitigation
measures are not included. As BUOW is now a candidate under CESA, CDFW
recommends that the Project’s mitigation measures be updated to reflect the species
updated status and recommends the following measures be incorporated into the
Project to avoid unauthorized take.
Recommended Mitigation Measure 1: BUOW Surveys Prior to Construction
CDFW recommends that surveys, following the “Burrowing Owl Survey Protocol and
Mitigation Guidelines” (CBOC 1993) and CDFW’s “Staff Report on Burrowing Owl
Mitigation” (CDFG 2012) be conducted within areas of suitable habitat the survey
season immediately prior to construction.
Recommended Mitigation Measure 2: BUOW Buffers
If BUOW burrows known to be currently or previously occupied by BUOW are found,
either during surveys or Project activities, CDFW recommends implementing a 500-
meter no-disturbance buffer around each burrow.
Recommended Mitigation Measure 3: BUOW Take Authorization
If BUOW or burrows known to be currently or previously occupied by BUOW are
found, either during surveys or Project activities, consultation with CDFW is
warranted to discuss how to implement the Project and avoid take . If avoidance is
not feasible, acquisition of a State Incidental Take Permit pursuant Fish and Game
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Code section 2081 subdivision (b), prior to any ground disturbing activities, would be
necessary in order to comply with CESA.
Crotch’s Bumble Bee (CBB)
The Project is within known geographic range of CBB and CBB have been recently
found in the area (CDFW 2024). The IS/MND indicates that proposed treatment well
area contains suitable habitat for the species, however, the IS/MND does not include
any evaluation for the species. The IS/MND includes a mitigation measure for general
special-status species surveys (BIO-2), however, CBB specific mitigation measures are
not included. CBB are known to inhabit areas of grasslands and scrub that contain
requisite habitat elements for nesting, such as small mammal burrows and
bunch/thatched grasses (Xerces Society et al. 2018; CDFW 2024), and these habitat
elements appear to be present within the Project site. The Project has the potential to
impact CBB nesting habitat, overwintering queen refugia, and result in direct mortality of
individuals. Without appropriate avoidance and minimization measures for CBB,
potentially significant impacts associated with the Project’s activities include burrow
collapse, inadvertent entrapment, reduced reproductive success, reduction in health
and vigor of bumble bee nests, and direct mortality of individuals. As such, CDFW
recommends the following:
Recommended Mitigation Measure 4: CBB Habitat Assessment
CDFW recommends a qualified biologist conduct a habitat assessment to
determine if the Project area and the immediate surrounding vicinity contain habitat
suitable to support CBB. Potential nesting sites, which include all small mammal
burrows, perennial bunch grasses, thatched annual grasses, brush piles, old bird
nests, dead trees, and hollow logs would need to be documented as part of the
assessment.
Recommended Mitigation Measure 5: CBB Surveys
If potentially suitable habitat is identified, CDFW recommends that a qualified
biologist conduct focused surveys for CBB, and their requisite habitat feat ures
following the methodology outlined in the Survey Considerations for California
Endangered Species Act Candidate Bumble Bee Species (CDFW 2023).
Recommended Mitigation Measure 6: CBB Buffers
If CBB is detected, then CDFW recommends that all small mammal burrows and
thatched/bunch grasses be avoided by a minimum of 50 feet to avoid take and
potentially significant impacts. If ground-disturbing activities will occur during the
overwintering period (October through February), consultation with CDFW is
warranted to discuss how to implement Project activities and avoid take. Any
detection of CBB prior to or during Project implementation warrants consultation
with CDFW to discuss how to avoid take.
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Recommended Mitigation Measure 7: CBB Take Authorization
If avoidance is not feasible, acquisition of a State Incidental Take Permit pursuant
Fish and Game Code section 2081 subdivision (b), prior to any ground disturbing
activities, would be necessary in order to comply with CESA.
South-Central California Coast (S-CCC) Steelhead
The locations of the proposed treatment wells are within approximately 300 feet of San
Luis Obispo Creek, which is occupied by S-CCC steelhead. It is unclear how much
groundwater will be extracted from the treatment wells, and if an analysis of impacts to
San Luis Obispo Creek, including impacts to steelhead, was conducted. Data from
Groundwater Sustainability Plans (GSP) groundwater monitoring sites within this area
indicate depth to groundwater is approximately less than 20 feet (DWR 2025). The
proposed treatment wells may be hydrologically connected to San Luis Creek. CDFW
recommends the IS/MND include an analysis of Project-related activities in relation to
potential impacts to San Luis Obispo Creek, including potential impacts to steelhead.
Editorial Comments and/or Suggestions
Sustainable Groundwater Management Act (SGMA), Interconnected Surface
Waters, and Groundwater Dependent Ecosystems (GDE):
Groundwater Sustainability Plans were prepared for the San Luis Obispo Valley. The
San Luis Obispo Valley Groundwater Basin (No. 3-009) is designated as a high priority
basin by the Department of Water Resources (DWR). SGMA defines sustainable
groundwater management as, “management and use of groundwater in a manner that
can be maintained during the planning and implementation horizon without causing
undesirable results (Water Code, § 10721 (v)).” The IS/MND states the proposed wells
are within the City of San Luis Obispo Groundwater Sustainability Agency (GSA), and
groundwater extraction would occur in compliance with SGMA and the approved San
Luis Obispo Valley Basin GSP, however, further details are not provided. It is unclear
how much groundwater will be extracted from the treatment wells and if an analysis of
impacts to interconnected surface waters and groundwater dependent ecosystems was
conducted in relation to the operation of the proposed treatment wells.
As stated above, both treatment wells are within approximately 300 feet of San Luis
Obispo Creek, and Figure 5-17 of the San Luis Obispo Valley Basin GSP (page 5-33)
indicates this location is an area identified as having potential GDEs with an estimated
depth to groundwater of less than or equal to 30 feet (SLO GSA 2021). Data from GSP
groundwater monitoring sites within this area also indicate depth to groundwater is
within this range (DWR 2025). CDFW recommends that the IS/MND include an analysis
of Project-related activities in relation to the San Luis Obispo Valley Basin GSP,
including analysis of potential undesirable results and adverse impacts to groundwater
dependent ecosystems including the biological resources listed above.
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Lake and Streambed Alteration (LSA): Based on GSP groundwater monitoring sites,
depth to groundwater in the area of the proposed treatment wells is less than 20 to 30
feet (DWR 2025). The proposed treatment wells may be hydrologically connected to
San Luis Creek, and it is unclear if operation of the treatment wells may impact the
natural flow of San Luis Creek. These Project activities may be subject to the
notification requirement of Fish and Game Code section 1602, which requires an entity
to notify CDFW prior to commencing any activity that may (a) substantially divert or
obstruct the natural flow of any river, stream, or lake; (b) substantially change or use
any material from the bed, bank, or channel of any river, stream, or lake (including the
removal of riparian vegetation); (c) deposit debris, waste or other materials that could
pass into any river, stream, or lake. “Any river, stream, or lake” includes those that are
ephemeral or intermittent as well as those that are perennial.
CDFW recommends coordination with CDFW staff prior to groundbreaking activities on -
site or submission of a Lake or Streambed Alteration (LSA) Notification to determine if
the activities proposed within the streams are subject to CDFW’s jurisdiction. CDFW is
required to comply with CEQA in the issuance of a LSA Agreement; therefore, if the
CEQA document approved for this Project does not adequately describe the Project and
its impacts, a subsequent CEQA analysis may be necessary for LSA Agreement
issuance. For additional information on notification requirements, please contact staff in
the Central Region Lake and Streambed Alteration Program at (559) 243-4593 or
R4LSA@wildlife.ca.gov, or the Program website:
https://wildlife.ca.gov/Conservation/LSA.
Nesting birds: CDFW recommends that Project ground-disturbing activities occur
during the bird non-nesting season; however, if ground-disturbing or vegetation-
disturbing activities must occur during the nesting season (Feb ruary 1st through
September 15th), the Project applicant is responsible for ensuring that implementation
of the Project does not result in violation of the Migratory Bird Treaty Act or relevant
Fish and Game Code sections as referenced above.
CDFW further recommends that a qualified biologist conduct a pre-construction survey
for active nests no more than 10 days prior to the start of ground or vegetation
disturbance to maximize the probability that nests that could potentially be impacted are
detected. CDFW also advises that surveys cover a sufficient area around the Project
site to identify nests and determine their status. A sufficient area means any area
potentially affected, either directly or indirectly, by the Project. In addition to direct
impacts (i.e., nest destruction), noise, vibration, and movement of workers or equipment
could also affect nests. CDFW recommends that a qualified biologist establish a
behavioral baseline of all identified nests. Once Project activities begin, CDFW
recommends having a qualified biologist continuously monitor nests to detect behavioral
changes resulting from the Project. If behavioral changes occur, CDFW recommends
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Shawna Scott
City of San Luis Obispo
January 9, 2025
Page 8
halting the work causing that change and consulting with CDFW for additional
avoidance and minimization measures.
If continuous monitoring of identified nests by a qualified biologist is not feasible, CDFW
recommends a minimum no-disturbance buffer of 250 feet around active nests of non -
listed bird species and a 500-foot no-disturbance buffer around active nests of non-
listed raptors. These buffers are advised to remain in place until the breeding season
has ended or until a qualified biologist has determined the birds have fledged and are
no longer reliant upon the nest or on-site parental care for survival. Variance from these
no-disturbance buffers is possible when there is a compelling biological or ecological
reason to do so, such as when the Project site would be concealed from a nest site by
topography. CDFW recommends that a qualified biologist advise and support any
variance from these buffers and notify CDFW in advance of implementing a variance.
ENVIRONMENTAL DATA
CEQA requires that information developed in environmental impact reports and negative
declarations be incorporated into a database, which may be used to make subsequent
or supplemental environmental determinations (Pub. Resources Code, § 21003, subd.
(e)). Accordingly, please report any special-status species and natural communities
detected during Project surveys to CNDDB. The CNNDB field survey form can be found
at the following link: https://www.wildlife.ca.gov/Data/CNDDB/Submitting-Data. The
completed form can be mailed electronically to CNDDB at the following em ail address:
CNDDB@wildlife.ca.gov. The types of information reported to CNDDB can be found at
the following link: https://www.wildlife.ca.gov/Data/CNDDB/Plants-and-Animals.
FILING FEES
The Project, as proposed, could have an impact on biological resources, and an
assessment of filing fees will be necessary. Fees are payable upon filing of the Notice of
Determination by the Lead Agency and serve to help defray the cost of environmental
review by CDFW. Payment of the fee is required in order for the underlying project
approval to be operative, vested, and final (Cal. Code Regs, tit. 14, § 753.5; Fish &
Game Code, § 711.4; Pub. Resources Code, § 21089).
CONCLUSION
CDFW appreciates the opportunity to comment on the IS/MND to assist the City of San
Luis Obispo in identifying and mitigating Project impacts on biological resources.
More information on survey and monitoring protocols for sensitive species can be found
at CDFW’s website (https://www.wildlife.ca.gov/Conservation/Survey-Protocols). Please
see the enclosed Mitigation Monitoring and Reporting Program (MMRP) table which
corresponds with recommended mitigation measures in this comment letter.
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Shawna Scott
City of San Luis Obispo
January 9, 2025
Page 9
If you have any questions regarding this letter or further coordination, please contact
Jackson Powell, Environmental Scientist, at the (559) 899-9758 by electronic mail at
Jackson.Powell@wildlife.ca.gov.
Sincerely,
Julie A. Vance
Regional Manager
ec: State Clearinghouse
Governor’s office of planning and Research
State.Clearinghouse@opr.ca.gov
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Shawna Scott
City of San Luis Obispo
January 9, 2025
Page 10
REFERENCES
California Burrowing Owl Consortium. 1993. Burrowing owl survey protocol and
mitigation guidelines. Pages 171-177 in Lincer, J. and K. Steenhof (editors).
1993. The burrowing owl, its biology and management. Raptor Research Report
Number 9.
California Department of Fish and Game. 2012. Staff report on burrowing owl mitigation.
California Department of Fish and Game, Sacramento, California, USA.
California Department of Fish and Wildlife. 2024. Biogeographic information and
observation system (BIOS). https://www.wildlife.ca.gov/Data/BIOS. Accessed
December 31, 2024.
California Department of Water Resources (DWR). 2025. Sustainable Groundwater
Management Act (SGMA) Data Viewer. Accessed January 3, 2025.
https://sgma.water.ca.gov/webgis/?appid=SGMADataViewer#currentconditions
Hatfield, R., S. Jepsen, R. Thorp, L. Richardson, and S. Colla. 2015. Bombus crotchii.
The International Union for Conservation of Nature red list of threatened Species.
https://www.iucnredlist.org/species/44937582/46440211
San Luis Obispo Valley Groundwater Basin Groundwater Sustainability Agencies (SLO
GSA). 2021. San Luis Obispo Valley Basin Groundwater Sustainability Plan.
October 2021.
Xerces Society for Invertebrate Conservation, Defenders of Wildlife, and Center for
Food Safety. 2018. A petition to the state of California fish and game commission
to list the Crotch’s bumble bee (Bombus crotchii), Franklin’s bumble bee
(Bombus franklini), Suckley cuckoo bumble bee (Bombus suckleyi), and western
bumble bee (Bombus occidentalis occidentalis) as Endangered under the
California Endangered Species Act. October 2018.
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Page 311 of 717
Attachment 1
CALIFORNIA DEPARTMENT OF FISH AND WILDLIFE
RECOMMENDED MITIGATION MONITORING AND REPORTING PROGRAM
(MMRP)
PROJECT: Groundwater Contamination Characterization Project (Project)
STATE CLEARINGHOUSE NO.: 2024120528
RECOMMENDED MITIGATION MEASURE STATUS/DATE/INITIALS
Before Disturbing Soil or Vegetation
BUOW
Mitigation Measure 1: BUOW Surveys Prior to
Construction
Mitigation Measure 3: BUOW Take Authorization
CBB
Mitigation Measure 4: CBB Habitat Assessment
Mitigation Measure 5: CBB Surveys
Mitigation Measure 7: CBB Take Authorization
During Construction
BUOW
Mitigation Measure 2: BUOW Buffers
CBB
Mitigation Measure 6: CBB Buffers
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State Water Resources Control Board
January 10, 2025
Shawna Scott
City of San Luis Obispo
879 Morro Street
San Luis Obispo, CA 93401
SAN LUIS OBISPO (CITY), INITIAL STUDY/MITIGATED NEGATIVE DECLARATION
(IS/MND), FOR THE GROUNDWATER CONTAMINATION CHARACTERIZATION
PROJECT (PROJECT); STATE CLEARINGHOUSE #2024120528
Dear Shawna Scott:
Thank you for the opportunity to review the IS/MND for the proposed Project. The State
Water Resources Control Board, Division of Drinking Water (State Water Board, DDW)
is responsible for issuing water supply permits pursuant to the Safe Drinking Water Act.
This Project is within the jurisdiction of the State Water Board, DDW’s Santa Barbara
District. DDW Santa Barbara District issues domestic water supply permit amendments
to public water systems pursuant to Waterworks Standards (Title 22 California Code of
Regulations [Cal Code Regs.] chapter 16 et. seq.). A public water system requires a
water supply permit amendment when changes are made to a domestic water supply
source, storage, or treatment and for the operation of new water system components-
as specified in the Cal. Code Regs. § 64556. The City will need to apply for a water
supply permit amendment for approval of a new source and operation of new treatment.
The State Water Board, DDW, as a responsible agency under the California
Environmental Quality Act (CEQA), has the following comments on the City’s IS/MND:
·In the IS/MND, under section 6 Description of the Project, please discuss the
operation of the wells and treatment system and implementation of the
monitoring program.
·When discussing the Project’s operational impacts for possible hazardous
materials, please discuss the granulated activated carbon replacement timeline,
testing, transportation, and disposal (PDF page 58).
·According to the Department of Water Resources (DWR), Sustainable
Groundwater Management Act Prioritization dashboard, the Project falls within
the San Luis Valley Groundwater Basin, which has been designated by the DWR
as a high priority basin under the Sustainable Groundwater Management Act.
o DWR’s April 27, 2023, approval letter for the 2022 Groundwater
Sustainability Plan talks about “a goal to maintain groundwater levels at
Page 313 of 717
Shawna Scott - 2 - January 10, 2025
historical low conditions minus a small margin of operational flexibility
designed to account for future drought conditions.” Please discuss the
City’s historical use of groundwater, how it compares to the two new
wells, and if this continued use has been considered as part of the long-
term sustainable management of the basin.
o Please discuss the amount of water that will be pumped per year and if
pumping will be seasonal and/or strategic. Please also discuss the City’s
requirement to monitor (PDF page 63). If changes will be made to
pumping based on monitoring results, please discuss the thresholds that
will trigger them and what actions will be taken.
When the CEQA review process is completed, please forward the following items with
the permit application to the State Water Board, DDW Santa Barbara District Office at
DWPDIST06@waterboards.ca.gov:
·Copy of the IS/MND and Mitigation Monitoring and Reporting Plan (MMRP);
·Copy of all comment letters received and the lead agency responses as
appropriate;
·Copy of the Resolution or Board Minutes adopting the IS/MND and MMRP; and
·Copy of the date stamped Notice of Determination filed at the San Luis Obispo
County Clerk’s Office and the Governor’s Office of Land Use and Climate
Innovation, State Clearinghouse.
Please contact Lori Schmitz of the State Water Board at (916) 449-5285 or
Lori.Schmitz@waterboards.ca.gov, for questions regarding this comment letter.
Sincerely,
Lori Schmitz
Environmental Scientist
Division of Financial Assistance
Special Project Review Unit
1001 I Street, 16th floor
Sacramento, CA 95814
Cc:
Governor’s Office of Land Use and Climate Innovation, State Clearinghouse
Jason Cunningham
District Engineer
Santa Barbara District
Page 314 of 717
CALTRANS DISTRICT 5
50 HIGUERA STREET | SAN LUIS OBISPO, CA 93401-5415
(805) 549-3101 | FAX (805) 549-3329 TTY 711
www.dot.ca.gov
January 9, 2025
Attn: Shawna Scott, Special Projects Manager
City of San Luis Obispo
Sent via email: sscott@slocity.org
RE: Caltrans Comments on the Groundwater Contamination Characterization Project
MND – SCH # 2024120528
Dear Ms. Scott,
Caltrans has reviewed the December 2024 Mitigated Negative Declaration (MND) for
the proposed groundwater contamination characterization project and offers the
following comments:
Any work within the State Right of Way will require an encroachment permit. Any right
of way and environmental issues (including stormwater) must be resolved prior to
submittal of the permit application.
Per the MND, the proposed work would place a water conveyance line within an
existing sewer conduit under Route 101, which would require a Caltrans encroachment
permit. The following items will be required as part of the encroachment permit
application package:
• An engineered plan and profile (signed, stamped, and dated by a CA civil
engineer) will be required for the proposed work. The plan and profile should
show the Route number, State right of way lines, edge of pavement, edge of
traveled way, and all existing utilities.
• Encasement is required for all utilities (except gravity flow sewer lines) that cross
the State highway right of way. Please refer to Section 603.3C of the
Encroachment Permit Manual for encasement requirements (it is doubtful that
the existing sewer conduit meets these requirements).
• By policy, trenchless technology is required for all underground utility installations.
Please refer to Section 603.6A of the Encroachment Permit Manual for trenchless
installation requirements. Please note Section 603.6A-2 “Geotechnical
Investigation,” which is required for all trenchless technology work, and Section
603.6A-3 “Geotechnical Design Report,” which is required if the bore diameter is
greater than 10” and the minimum clearance is less than eight times the bore
diameter.
• Any open excavation 5’ or greater in depth will require engineered shoring
plans.
Page 315 of 717
The encroachment permit application form, directions to complete the form, and plan
requirements can be found at the following web address:
https://dot.ca.gov/programs/traffic-operations/ep/applications. Completed
application packages may either be emailed to d5.permits@dot.ca.gov or submitted
through the Caltrans Encroachment Permit System (CEPS) public portal.
Thank you for the opportunity to provide comment, and Caltrans looks forward to
continued coordination with the City of San Luis Obispo on this and future projects.
Sincerely,
Shelby Fredrick
Local Development Review Coordinator
Caltrans, District 5
Cc: Veronica Lezama, Branch Chief, Caltrans D5 Regional Planning South
Cc: Chris Bjornstad, Local Development Review Coordinator, District 5
Page 316 of 717
Appendix E
Mitigation Monitoring and Reporting Program
Page 317 of 717
Groundwater Contamination Characterization Project - Mitigation Monitoring and Reporting Program
Mitigation Measures Monitoring Program
Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
Aesthetics
AES-1 Nighttime Work Requirements
In the event nighttime work is
necessary during the project
construction phase, any portable
lighting shall be shielded and/or
directed away from adjacent
properties. Night lighting for
construction activities shall be the
minimum necessary to ensure safety
and security for nighttime activities
and operations. Lighting at the project
site shall consist of light-emitting
diode lights in all areas where
nighttime construction activities will
occur and be either motion-activated
or use timers to ensure safety and
security and reduce the impact of
additional light pollution at night. The
City shall verify compliance with the
construction night lighting
requirements via an inspection during
nighttime construction activities.
City of San Luis
Obispo
Construction
Contractor
Incorporate measure into
plans and specifications.
City staff conduct
inspection to confirm
compliance.
City of San Luis
Obispo
During
construction,
if nightwork is
conducted.
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Mitigation Measures Monitoring Program
Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
Air Quality
AQ-1 Odor Reduction
Where construction activities occur
within 50 feet of a sensitive receptor,
the construction contractor shall
implement the following additional
idling restrictions, which shall be
shown on grading and construction
plans:
• Idling Restrictions Near Sensitive
Receptors for Both On- and Off-
Road Equipment
• Staging and queuing areas shall
be located at the greatest
distance feasible from sensitive
receptor locations;
• Diesel idling while equipment is
not in use is not permitted;
• Use of alternative-fueled
equipment is recommended
whenever possible; and
• Signs that specify the no-idling
requirements shall be posted and
enforced at the construction site.
The City Utilities Department shall
verify these measures are located on
construction plans prior to the start of
construction. Once during
City of San Luis
Obispo
Construction
Contractor
Incorporate measure into
plans and specifications.
City staff conduct
inspection to confirm
compliance.
City of San Luis
Obispo
During
construction
within 50 feet
of a sensitive
receptor.
Page 319 of 717
Mitigation Measures Monitoring Program
Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
construction, City Inspector shall visit
the project site to verify these idling
restrictions have been implemented.
Biological Resources
BIO-1 Worker Environmental
Awareness Program
Prior to initiation of construction
activities at the treatment well site, all
personnel associated with project
construction shall attend a Worker
Environmental Awareness Program
(WEAP) training, conducted by a
qualified biologist, to aid workers in
recognizing special-status species
and nesting birds that may occur
within the project site. The specifics of
this program shall include
identification of special-status species
with potential to occur, a description
of their regulatory status and habitat
requirements, general ecological
characteristics of any other sensitive
resources, and a review of the limits
of construction and measures
required to avoid and/or reduce
impacts to biological resources within
the project site. A fact sheet
conveying this information shall also
be prepared for distribution to the
City of San Luis
Obispo
Construction
Contractor
Consulting Biologist
Incorporate measure into
plans and specifications.
Provide WEAP training
and provide materials at
pre-construction
meeting(s).
City of San Luis
Obispo
Prior to
construction
(pre-
construction
meeting).
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Mitigation Measures Monitoring Program
Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
construction contractor. All employees
shall sign a form provided by the
biologist indicating they have
attended the WEAP training and
understand the information presented
to them. The construction foreman
shall ensure crew members are
aware of project boundaries and
adhere to the mitigation measures
designed to avoid or minimize effects
to listed species, nesting birds, and
other special-status species.
BIO-2 Pre-Construction Survey for
Special-Status Wildlife Species
A qualified biologist shall conduct a
pre-construction survey of the
treatment well site and adjacent
habitat no more than two weeks prior
to the start of construction at the
treatment well site. The biologist shall
document the presence or absence of
any special-status wildlife species
with potential to occur within the
treatment well site plus a 50-foot
buffer. The pre-construction survey
shall include surveys for burrowing
owl that follow the “Burrowing Owl
Survey Protocol and Mitigation
Guidelines” (California Burrowing Owl
Consortium [CBOC] 1993) and
City of San Luis
Obispo
Construction
Contractor
Consulting Biologist
Incorporate measure into
plans and specifications.
Consulting biologist to
conduct pre-construction
surveys, provide
documentation of surveys
and any additional
actions.
City of San Luis
Obispo
Prior to
construction
(no more than
two weeks
prior to start
of
construction)
and
immediately
prior to
construction.
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Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
CDFW’s “Staff Report on Burrowing
Owl Mitigation” (California
Department of Fish and Game
[CDFG] 2012) within areas of suitable
habitat during the survey season
immediately prior to construction.
If special-status species are observed
onsite during the pre-construction
surveys, they shall be allowed time to
leave or be relocated prior to the
initiation of construction activities. If
special-status species are present
during construction activities, they
shall be handled in accordance with
Mitigation Measure BIO-7.
BIO-3 Burrowing Owl Buffers
If burrows known to be currently or
previously occupied by burrowing owl
are found, either during surveys or
project activities, a 500-meter no-
disturbance buffer shall be
established around each burrow.
City of San Luis
Obispo
Construction
Contractor
Consulting Biologist
Incorporate measure into
plans and specifications.
Comply with no-
disturbance buffer
requirements.
City of San Luis
Obispo
Prior to
construction
and during
construction.
BIO-4 Burrowing Owl Take
Authorization
If burrowing owl individuals or
burrows known to be currently or
previously occupied by burrowing owl
are found, either during surveys or
City of San Luis
Obispo
Construction
Contractor
Consulting Biologist
Incorporate measure into
plans and specifications.
Consult with CDFW if
individuals or burrows are
observed.
City of San Luis
Obispo
Prior to
construction
and during
construction.
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Mitigation Measures Monitoring Program
Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
project activities, the City of San Luis
Obispo shall consult with CDFW to
discuss how to implement the project
and avoid take. If avoidance is not
feasible, acquisition of a State
Incidental Take Permit pursuant to
California Fish and Game Code
Section 2081 subdivision (b), prior to
any ground disturbing activities, shall
be required in order to comply with
the California Endangered Species
Act.
BIO-5 Crotch’s Bumble Bee Habitat
Assessment and Surveys
A qualified biologist shall conduct a
habitat assessment to determine if the
project area and the immediate
surrounding vicinity contain habitat
suitable to support Crotch’s bumble
bee. The assessment shall document
potential nesting sites, which include
all small mammal burrows, perennial
bunch grasses, thatched annual
grasses, brush piles, old bird nests,
dead trees, and hollow logs.
If potentially suitable habitat for
Crotch’s bumble bee is identified in
the habitat assessment, the qualified
biologist shall conduct focused
surveys for Crotch’s bumble bee and
City of San Luis
Obispo
Construction
Contractor
Consulting Biologist
Incorporate measure into
plans and specifications.
Complete habitat
assessment and comply
with CDFW requirements
for focused surveys.
Provide documentation of
assessment and surveys.
City of San Luis
Obispo
Prior to
construction.
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Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
their requisite habitat features,
following the methodology outlined in
the Survey Considerations for
California Endangered Species Act
Candidate Bumble Bee Species
(CDFW 2023).
BIO-6 Crotch’s Bumble Bee Buffers
and Take Authorization
If Crotch’s bumble bee is detected
during the required habitat
assessment and surveys, all small
mammal burrows and thatched/bunch
grasses shall be avoided by a
minimum of 50 feet to avoid take of
Crotch’s bumble bee. If ground-
disturbing activities would occur
during the overwintering period
(October through February), the City
of San Luis Obispo shall consult with
CDFW to discuss how to implement
project activities and avoid take. Any
detection of Crotch’s bumble bee prior
to or during project implementation
warrants consultation with CDFW to
discuss how to avoid take.
If avoidance is not feasible,
acquisition of a State Incidental Take
Permit pursuant to California Fish and
Game Code Section 2081 subdivision
(b), prior to any ground disturbing
City of San Luis
Obispo
Construction
Contractor
Consulting Biologist
Incorporate measure into
plans and specifications.
Comply with avoidance
requirements and consult
with CDFW if species is
detected.
City of San Luis
Obispo
Prior to
construction
and during
construction.
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Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
activities, would be required in order
to comply with the California
Endangered Species Act.
BIO-7 Biological Monitoring and
Special-Status Species Relocation
A qualified biologist shall be onsite at
the treatment well site during all
vegetation removal, initial ground
disturbing activities, and/or during any
construction activities that may impact
sensitive biological resources. If the
biologist discovers special-status
animal species on the project site, the
biologist shall have the authority to
temporarily halt or redirect work to
avoid potential impacts. If avoidance
is not feasible, the biologist shall be
responsible for relocating wildlife
species out of the treatment well site
in accordance with the requirements
of applicable regulatory agencies,
such as CDFW or the United States
Fish and Wildlife Service. Special-
status wildlife shall not be handled
without prior permission from the
necessary regulatory agencies.
Species-specific monitoring
requirements may be superseded or
added to by resource agency permits
and/or incidental take authorizations.
City of San Luis
Obispo
Construction
Contractor
Consulting Biologist
Incorporate measure into
plans and specifications.
Conduct biological
monitoring as specified
and provide monitoring
documentation.
Comply with
avoidance/relocation
requirements, and
consult with applicable
regulatory agencies prior
to species handling.
City of San Luis
Obispo
During
construction.
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Mitigation Measures Monitoring Program
Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
Following the relocation of wildlife, the
biologist shall submit a report to the
City confirming the methodology and
results of relocating the wildlife.
BIO-8 Nesting Bird Surveys
A preconstruction nesting bird survey
shall be conducted by a qualified
biologist no more than 14 days prior
to initiation of project construction
activities. The survey shall be
conducted within the treatment well
site and include a 50-foot buffer for
passerines and a 500-foot buffer for
raptors. The survey shall be
conducted by a biologist familiar with
the identification of avian species
known to occur in the region and shall
focus on trees, vegetated areas, and
other potential nesting within the
vicinity of the treatment well site. If
active nests are identified in the
survey, an appropriate avoidance
buffer (typically 50 feet for passerine
species and 500 feet for raptors) shall
be determined and demarcated by the
biologist with high visibility material
located within or adjacent to the
treatment well site. All project
personnel shall be notified as to the
existence of the buffer zones and to
City of San Luis
Obispo
Construction
Contractor
Consulting Biologist
Incorporate measure into
plans and specifications.
Consulting biologist to
conduct pre-construction
surveys, provide
documentation of surveys
and any additional
actions.
Comply with avoidance
requirements.
City of San Luis
Obispo
Prior to
construction
(no more than
two weeks
prior to start
of
construction).
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Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
avoid entering buffer zones during the
nesting season. No project
construction activities shall occur
within the buffer until the biologist has
confirmed that breeding/nesting is
complete, and the young have
fledged the nest. Encroachment into
the buffer shall occur only at the
discretion of the qualified biologist.
Cultural Resources
CUL-1 Workers Environmental
Awareness Program Training
All construction personnel and
monitors who are not trained
archaeologists shall be briefed
regarding unanticipated discoveries
prior to the start of construction
activities. A basic presentation shall
be prepared and presented by a
qualified archaeologist and Chumash
Tribal Representative to inform all
personnel working on the project
about the archaeological sensitivity of
the area. The purpose of the WEAP
training is to provide specific details
on the kinds of archaeological
materials that may be identified during
construction of the project and explain
the importance of and legal basis for
City of San Luis
Obispo
Construction
Contractor
Consulting
Archaeologist
Incorporate measure into
plans and specifications.
Consulting archaeologist
and Native American
tribal representative to
conduct WEAP training.
Complete and retain
documentation.
City of San Luis
Obispo
Prior to
construction
(pre-
construction
meeting).
Page 327 of 717
Mitigation Measures Monitoring Program
Implementation
Responsibility
Monitoring and
Reporting Action
Monitoring
Responsibility
Monitoring
Schedule
the protection of significant
archaeological resources. Each
worker shall also learn the proper
procedures to follow in the event that
archaeological resources or human
remains are uncovered during
ground-disturbing activities. These
procedures include work curtailment
or redirection, and the immediate
contact of the on-call archaeologist
and if appropriate, Native American
representatives. The necessity of
training attendance shall be stated on
all construction plans and the City of
San Luis Obispo shall maintain
records demonstrating construction
worker WEAP participation.
CUL-2 Archaeological and Native
American Monitoring
Prior to any ground disturbing
activities, the project proponent shall
retain an archaeologist meeting the
Secretary of the Interior’s
Qualifications Standards (NPS 1983)
(Qualified Archaeologist) to oversee
the implementation of this measure.
Prior to any ground disturbing
activities, the archaeologist shall
provide a Cultural Resources
Mitigation and Monitoring Plan
City of San Luis
Obispo
Construction
Contractor
Consulting
Archaeologist
Incorporate measure into
plans and specifications.
Prepare and implement
CRMMP, and comply with
monitoring, notification,
and
reporting/documentation
requirements.
City of San Luis
Obispo
Prior to and
during
construction.
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(CRMMP) for review and approval by
the City of San Luis Obispo. The
CRMMP should include, but not be
limited to, the following:
a. A list of personnel involved in the
monitoring activities;
b. Description of Native American
involvement;
c. Description of how the monitoring
shall occur;
d. Description of location and
frequency of monitoring (e.g., full
time, part time, spot checking);
e. Description of what resources
may be encountered;
f. Description of circumstances that
would result in the halting of work
at the project site;
g. Description of procedures for
halting work on the site and
notification procedures;
h. Description of monitoring
reporting procedures; and
i. Provide specific, detailed
protocols for what to do in the
event of the discovery of human
remains.
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The Qualified Archaeologist shall
provide conditional monitoring as well
as on call response in the case of an
inadvertent discovery of
archaeological resources. Given the
developed nature of monitoring well
locations MW-01 through MW-08 and
MW-10 through MW-12, and the
method of construction activities
proposed (i.e., drilling), monitoring at
these locations should be limited to
spot-checking and periodic
examination of soils through selective
sampling of soils brought to the
surface as a result of the drilling
activities. All construction-related
ground disturbances, including
clearing/grubbing and drilling, within
the treatment well site, west and east
of U.S. 101) and west of San Luis
Obispo Creek be monitored by an
archaeologist and a Native American
representative. In general,
archaeological, and Native American
monitoring shall be limited to initial
ground disturbance, which is defined
as construction-related earthmoving
of sediments from their native place of
deposition and does not include any
secondary movement of sediment
that might be required for the project.
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The Qualified Archaeologist may
adjust monitoring efforts as needed
(increase, decrease, or discontinue
monitoring frequency) based on the
observed potential for construction
activities to encounter archaeological
deposits. The Qualified Archaeologist
shall be responsible for maintaining
daily monitoring logs.
Throughout the course of project
construction activities, if a discovery is
made by construction personnel and
a monitor is not present, the protocols
and procedures outlined in the
Mitigation Measure CUL-3,
Unanticipated Discovery of
Archaeological Resources, shall be
followed. Following the completion of
construction, the Qualified
Archaeologist shall prepare an
archaeological monitoring report for
submittal to the City and the CCIC
with the results of the archaeological
monitoring program.
CUL-3 Unanticipated Discovery of
Archaeological Resources
In the event that archaeological
remains are encountered during
construction, City staff shall be
notified and all work within 50 feet of
City of San Luis
Obispo
Construction
Contractor
Incorporate measure into
plans and specifications.
Comply with avoidance,
monitoring, notification,
evaluation, and reporting/
City of San Luis
Obispo
During
construction.
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the find shall be halted until the find is
evaluated by the Qualified
Archaeologist or other designated
archaeologist working under the
direction of the Qualified
Archaeologist and appropriate
mitigation, if necessary, is
implemented. Native American tribal
representatives shall be notified. If
archaeological remains are identified,
the resource shall be evaluated for
significance under City Archaeological
Resource Preservation Program
Guidelines, and further treatment
measures, including but not limited to
avoidance consistent with City
General Plan Policies, Phase 2
Subsurface Archaeological Resource
Evaluation, or Phase 3 Archaeological
Data Recovery Excavation may be
required. Work within 50 feet of the
find shall not resume until
authorization is received from the
City. This measure shall be included
on all construction plans.
Consulting
Archaeologist
documentation
requirements.
Geology and Soils
GEO-1 Unanticipated Discovery of
Paleontological Resources
City of San Luis
Obispo
Incorporate measure into
plans and specifications.
City of San Luis
Obispo
During
construction.
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In the event of a fossil discovery by
construction personnel at the
treatment well site, the construction
contractor shall halt all construction
activities within the 50 feet of the
fossil, and a Qualified Professional
Paleontologist shall be retained to
evaluate the find prior to resuming
construction activity. If it is determined
the fossil(s) is (are) scientifically
significant, the Qualified Professional
Paleontologist shall complete the
following conditions to mitigate
impacts to significant fossil resources:
• Fossil Salvage. If fossils are
discovered, the Qualified
Professional Paleontologist shall
have the authority to halt or
temporarily divert construction
equipment within 50 feet of the
find until the Qualified
Professional Paleontologist
evaluate the discovery and
determine if the fossil may be
considered significant. Bulk
matrix sampling may be
necessary to recover small
invertebrates or microvertebrates
from within paleontologically
sensitive deposits.
Construction
Contractor
Consulting
Paleontologist
Comply with avoidance,
notification, evaluation,
and reporting/
documentation
requirements.
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• Fossil Preparation and Curation.
Once salvaged, significant fossils
shall be identified to the lowest
possible taxonomic level,
prepared to a curation-ready
condition, and curated in a
scientific institution with a
permanent paleontological
collection along with all pertinent
field notes, photos, data, and
maps. Fossils of undetermined
significance at the time of
collection may also warrant
curation at the discretion of the
Qualified Professional
Paleontologist.
• Final Paleontological Report. The
Qualified Professional
Paleontologist shall submit a
report describing the results of
the paleontological monitoring
efforts associated with the
project. The report shall include a
summary of the field and
laboratory methods, an overview
of the project geology and
paleontology, a list of taxa
recovered (if any), an analysis of
fossils recovered (if any) and their
scientific significance, and
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recommendations. The report
shall be submitted to the City.
Noise
N-1 Noise Reducing Best
Management Practices
During monitoring well installation at
MW-01, MW-02, MW-03, MW-06, and
MW-10, the following construction
noise best management practices
shall be adhered to:
• Stationary construction
equipment that generates noise
that exceeds 60 dBA shall be
shielded with the most modern
noise control devices (i.e.
mufflers, lagging, and/or motor
enclosures).
• Impact tools (e.g., drills) used for
project construction shall be
hydraulically or electrically
powered wherever possible to
avoid noise associated with
compressed-air exhaust from
pneumatically powered tools.
• Where use of pneumatic tools is
unavoidable, an exhaust muffler
on the compressed-air exhaust
shall be used.
City of San Luis
Obispo
Construction
Contractor
Incorporate measure into
plans and specifications.
Comply with notification
and noise reduction
measures at specified
monitoring well sites.
City of San Luis
Obispo
Prior to (no
less than 21
days prior to
construction)
and during
construction.
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• All construction equipment shall
have the manufacturers’
recommended noise abatement
methods installed, such as
mufflers, engine enclosures, and
engine vibration insulators, intact
and operational.
• All construction equipment shall
undergo inspection at periodic
intervals to ensure proper
maintenance and presence of
noise control devices (e.g.,
mufflers, shrouding, etc.).
• At least 21 days prior to the start
of construction, notify off-site
businesses and residents within
150 feet of construction of
planned construction activities.
The notification shall provide brief
description of the project,
activities that would occur, hours
of construction, the duration of
construction, and a phone
number to the City Community
Development Department for the
public to direct noise-related
complaints.
N-2 City Approval and Personnel
Briefing
City of San Luis
Obispo
Incorporate measure into
plans and specifications.
City of San Luis
Obispo
Prior to (pre-
construction
meeting) and
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Construction plans shall note
construction hours, truck routes, and
all construction noise best
management practices, and shall be
reviewed and approved by the City
Utilities Department prior to
advertisement of the construction
request for bids. All construction
workers shall be briefed at a
preconstruction meeting on
construction hour limitations and how,
why, and where best management
practices are to be implemented.
Construction
Contractor
Comply with briefing
requirements.
during
construction.
Tribal Cultural Resources
Implement CUL-1, CUL-2, and CUL-
3.
City of San Luis
Obispo
Construction
Contractor
Consulting
Archaeologist
See above See above See above
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