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sources. As of August 2019, DDW has issued a Notification Level of 5.1 parts per trillion (ppt) for PFOA, a Notification Level of 6.5 ppt for PFOS, and a Response Level of 70 ppt for PFOA and PFOS combined. As part of a statewide testing program being led by DDW, Zone 7 and the City have conducted testing for PFOA and PFOS in water supplies. For Zone 7, only the Mocho-1 Well tested above the combined PFOA and PFOS Response Level. As a result, Zone 7 immediately made the well the last to operate to meet water demands. When required to operate, the well will be blended with other wells or it will be treated by the Mocho Groundwater Demineralization Facility so that concentrations are below the Response Level. Zone 7's surface water supply was non-detect for PFOA and PFOS. For the City, only Well 8 tested above the combined PFOA and PFOS Response Level. As a result, staff immediately placed Well 8 into the last priority facility to operate when trying to meet water demands. Well 8 has not operated since and is only anticipated to operate under abnormal conditions such as extreme peak demand periods or if there are failures of other supply facilities. RECOMMENDATION 1. Receive a presentation on the City's water system and PFAS; 2. Confirm support for staff near-term actions related to PFAS that includes implementation of operational strategies and public notification as detailed in the Conclusion section of this report. 3. Confirm support for staff long-term actions related to PFAS that includes treatment evaluations, alternative water supply evaluations, financial impact evaluations, increased legislative tracking, and regional planning as detailed in the Conclusion section of this report. FINANCIAL STATEMENT The recommendations contained herein will result in additional capital and operational costs that will impact the Water Enterprise Fund. It is recommended that these impacts be evaluated as part of the current water rate study. BACKGROUND Water Supply The City of Pleasanton (City) distributes approximately 4,500 million gallons of treated water a year to 22,000 customers. Approximately 75% of that distributed water is sourced from the Zone 7 Water Agency (Zone 7). The other 25% is sourced directly by the City. Zone 7 has two sources of water: 1) surface water and 2) groundwater. In 2018, Zone 7's regional split of surface water to ground water supply was 85% to 15%. Zone 7's major sources of surface water are State Water Project water conveyed through the Delta and local runoff water from Del Valle Reservoir. These sources are treated (i.e. clarification, filtration, and disinfection using chloramination) at Zone 7's Del Valle Water Treatment Plant and Patterson Pass Water Treatment Plant and then pumped into large transmission lines for delivery to the Tri-Valley Water Retailers (City of Pleasanton, City of Livermore, Cal-Water Livermore, and Dublin San Ramon Services District). Zone 7 Page 2 of 13