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completion of the basis of design phase (when the project scope and cost estimate is more clearly defined) additional funding from Fund 421 Water Replacement Capital Improvement Program would be requested to advance the project. CIP 22179 — Well 8 Facility Improvements and CIP 23282 — Well 5/6 Facility Improvements would be eliminated as the work for these projects would be included in the PFAS Treatment and Wells 5, 6, and 8 Rehabilitation Project. BACKGROUND At the November 5, 2019 City Council meeting, staff provided a presentation on PFAS and their impacts to the City's water system. This report provides a status update on PFAS since that time including the topics of regulation, City and Zone 7 Water Agency (Zone 7) testing, cu rrent operational practices, and publicoutreach. PFAS are a large group of non-regulated substances used in products such as carpets, clothing, fabrics, paper packaging forfood, non-stick cookware, and fire -retarding foam that resist heat, oil, stains, and water. Although not regulated, the DDW has established advisory levels due to health concerns. As of February 2020, DDW has established Notification Levels of 5.1 parts per trillion (ppt) and 6.5 ppt for PFOA and PFOS, respectively. DDW has also established Response Levels of 10 ppt and 40 ppt for PFOA and PFOS, respectively. DDW has provided a tentative schedule to regulate PFOA and PFOS by establishing maximum contaminant levels (MCLs) by winter of 2023. DDW has also started the process of reviewing other PFAS (beyond PFOA and PFOS) for possible regulation, but schedu le forestablish ing Notification Levels, Response Levels, or MCLs has not yet been identified. In March of 2019, the City and Zone 7 received orders from DDW to test for the presence of PFOA and PFOS in the grou ndwater supply. Results have shown that all three City wells (shown on Attachment 1) contain the presence of PFOA and PFOS. However, only Well 8 has tested above the Response Level for PFOS. As a result, the City has not operated that well since the beginning of testing in June 2019. For Zone 7 wells (shown on Attachment 1), test results have shown thatall wells, except for the Hopyard wells, contain the presence of PFOA and PFOS. However, only the well known as Mocho 1 has tested above the Response Level for PFOS. Zone 7 is continuing their operational practices of blending waterfrom wells and/or treating well water at the Demineralization Facility to ensure water delivered to turnouts are kept below response levels. The City continues to post PFOA and PFOS test data for City and Zone 7 wells on its PFAS website. Results were also included in the recently issued 2019 Consumer Confidence Report (CCR) also available on the City and Zone 7's websites. On July 15, 2020, City staff provided a comprehensive PFAS status update to the Tri - Valley Water Subcommittee Members: Vice -Mayor Narumand CouncilmemberBrown . The Committee recommended that thefull City Council receive status update on PFAS including an overview of the City's work plan and findings related to the feasibility of self -implementing PFAS treatment at City wells. Staff is seeking Council's approval to prepare a basis of design report for PFAS Treatment and Wells 5, 6, and 8 Rehabilitation Project and other actions as described in the recommendations section of this report. Page 2 of 9