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study is completed and the City Council provides direction regarding long-term water supply; and 3) Conduct a Public Hearing to accept the City's 2022 Public Health Goals Report. FINANCIAL STATEMENT There are no fiscal impacts from receiving the Zone 7 groundwater modeling and PFAS contamination presentation and from accepting the City's 2022 Public Health Goals Report. Relative to the purchase of replacement water supply necessitated by taking wells 5 and 6 offline, Zone 7 has indicated that it can provide the additional water, initially through a short-term arrangement. This cost would be funded by the Zone 7 pass-through to utility rate payers. BACKGROUND Zone 7 Groundwater Model and PFAS Contamination Presentation Zone 7 recently completed a groundwater modeling analysis of mobilization of the PFAS plume under different drought management pumping scenarios. The study used an existing MODFLOW groundwater flow model and the United States Geological Survey (USGS) MT3 - Groundwater Solute Transport Simulator for the basin to analyze mobilization of the plumes as compared to baseline conditions. There were five scenarios that modeled varied pumping rates for Zone 7's production wells, with one baseline scenario reflecting average pumping condition and four scenarios entailing increased pumping rates in selected wells in response to supplying water needs during drought. All scenarios span a 20-year simulation period and begin with a three-year drought. The findings from the modeling study were presented to the Zone 7 Board on August 31, 2022. Zone 7 General Manager Valerie Pryor will provide this same presentation to the City Council as foundational information for current and future decision-making. It should be noted that given the timeframe in which the study was conducted, it did not account for the City of Pleasanton's recent request for Zone 7 to provide up to 3,500 Acre-Foot (AF) to replace the City's groundwater pumping allotment. PFHXS Health Advisory and City Water Well Operation Perfluorohexanesulfonic acid (PFHxS) is a member of a large class of chemicals known as per- and polyfluoroalkyl substances (PFAS). PFAS do not occur naturally, and their presence in the environment is due to human activity; they are chemical compounds that act as a surfactant used in numerous commercial products such as water- and stain-repellents and fire-fighting foams. New State health-based notification and response levels have been established for PFHxS. In response to the State Water Resources Control Board Division of Drinking Water's (DDW) February 2020 request, on March 17, 2022, the Office of Environmental Health Hazard Assessment (OEHHA) provided a PFHxS notification level recommendation of 2 ng/L (ppt). Health and Safety Code (HSC) section 116455 describes notification levels as nonregulatory, health-based advisory levels established as precautionary measures for contaminants that may be candidates for maximum contaminant levels, but which have not yet completed the regulatory standard setting process and are not drinking Page 2 of 5