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HomeMy WebLinkAbout05/06/2003, C9 - ARCHEOLOGICAL SERVICES - DOWNTOWN PIPELINE PROJECTS council "lay 6, 2003 j acEnaa wpopt �N� cq CITY O F SAN LUIS OBISPO FROM: Michael D. McCluskey, Director of Public Works Prepared By: Barbara Lynch Civil EngineeI SUBJECT: ARCHEOLOGICAL SERVICES —DOWNTOWN PIPELINE PROJECTS CAO RECOMMENDATION 1. Approve additional funding for the completion of archeological monitoring for the downtown pipeline projects. DISCUSSION In November of last year, the City Council authorized the advertising of two projects to replace existing water, sewer and storm drain lines in the downtown. The environmental document included a mitigation measure for archeological monitoring. During the preparation of the environmental document, Public Works obtained the services of an archeological firm to complete a Phase I study. That study identified the potential for discovery of primarily historical resources and recommended that an archeologist be present during excavations in previously undisturbed areas. The archeologist was also to include monitoring by a Native American where it seemed appropriate. It was believed this recommendation affected the water and storm drain portion of the work primarily. Sewer lines are normally replaced within an existing, and therefore previously disturbed, trench. Public Works has established an on-call resource for environmental services such as this. That list was established through a Request for Qualifications process approved by the City Council and authorizes the CAO to execute Purchase Orders up to $50,000. A contract for monitoring services was obtained and authorized by the CAO. This firm prepared a monitoring plan which was approved by the Community Development Department in accordance with the City's established archeological guidelines. Currently, construction work is progressing at two separate work sites with two separate contractors. City staff is providing coordination of the work efforts and a single archeological monitoring program has been established for the two efforts. The first phase of the work, for both projects currently underway, was the replacement of sections of sewer line. Soon after the work began, it became apparent the existing sewer line had been installed in a hand dug trench. Modern equipment cuts a much wider trench. The trench walls exposed during the current work were undisturbed and therefore fell under the requirement for monitoring. The result is an unanticipated cost to the Wastewater Fund.. Additionally, during digging in the lower Palm Street area (near Nipomo Street) a "hearth" was discovered in the sidewall of the trench. This is to the layman, a fire pit. Testing is underway to C CouncilAgendaReport—Archeological Services—Downtown Pipeline Projects Page 2 determine the era, but the presence of the hearth has raised the possibility the hearth is part of a larger "site." This possibility resulted in greater scrutiny of the Palm street work area by the archeologist and a Native American monitor. A third monitor was then needed at the other work area and consequently the costs have increased. FISCAL IMPACT Staff's previous experience working in the street right of way insensitive areas was that little if anything of significance is found. The original funding level for archeological services was based on 1) previous experience 2) no monitoring would be needed for the sewer work and 3) only minimal materials, bits and pieces, would be found in the trench areas. We currently anticipate; based on the age and location of the sewer lines, the entire project will have to be monitored. Staff has held several discussions with the monitoring company to emphasize the need to keep costs to a minimum. The total cost for monitoring is estimated to be$249,000. This estimate is based on a combination of costs to date, potential savings with improved coordination and staffing control and the speed of construction by the Contractors so far. Water Fund Creek& Flood Fund Sewer Fund Total Monitoring Estimate: $ 86,000 $ 10,000 $ 153,000 $ 249,000 Budget to Date: $40,500 $4,500 $ 0 $ 45,000 Additional Funding Required: $45,500 $5,500 $153,000 $ 204,000 Funds Available: 1 $ 106,000 $ 80,000* $ 177,000 * CIP Reserve There are no funds currently available in the Creek and Flood Protection Fund. Additional funding for the monitoring attributed to the storm drain work will come from the CIP Reserve Account. These additional costs will impact delivery of anticipated projects for pipeline replacements in the water and sewer funds. Projects would continue to be done in priority order with lowest priority projects shifted to the next year. g.\-current pmj=s\semA9M61 dt sever-watertdocumems\1-staff repods\9MW add amh$.da