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• Construct a Centralized Treatment Facility at the OSC that provides PFAS treatment, disinfection, and fluoridation of groundwater from Wells 5, 6, and 8 and room for expansion to accommodate potential future regulations. The recommended PFAS treatment media is granular activated carbon (GAC). However, it is recommended that the PFAS treatment system be designed to allow the use of either GAC media or ion-exchange media (IX) in the future due to the uncertainty of regulations, volatility of media pricing, and rapidly progressing field of research. • Construct a new 18-inch pipeline to pump groundwater from Wells 5 and 6 to the OSC for treatment. Note that the Well 8 facility is located at the OSC. • Upsize a 14-inch treated water distribution main on Santa Rita Road (between Valley Ave. and Black Ave.) to 20-inch to mitigate the impacts of Wells 5 and 6 groundwater being introduced into the treated water distribution system at a new location. • Rehabilitate the existing Well 8 facility (originally constructed in 1992) to restore original pumping capacities (which have been reduced due to turbidity issues) and to replace equipment/systems that have reached the end of their useful life. • Abandon the existing Well 5 facility (originally constructed in 1962) since rehabilitation is not recommended at its existing location. Construct a new facility named Well 9 that is located at Amador Park. Test drilling during final design is required to confirm adequacy of the water aquifer at this location. The grass field at the Alisal Elementary School has been identified as an alternative location to explore in the event test drilling determines Amador Park is not a feasible location. • Rehabilitate the existing Well 6 facility (originally constructed in 1965) including replacement of the well casing and equipment/systems that have reached the end of their useful life. Upon completion, the facility would be renamed to Well 10. • The project schedule includes commissioning the rehabbed Well 8 facility, new Well 9 facility, new pipeline, and new CTF by May 2024, around the time DDW is anticipated to issue PFAS MCLs. After this point, existing Well 5 will be permanently decommissioned and existing Well 6 shut down for rehabilitation with an estimated commissioning date of December 2024. • The estimated construction cost is $34,600,000. The estimated overall project cost (including design services, construction change order contingency, and construction support services) is $46,000,000. Regional Alternatives Parallel to preparation of the BODR, City staff has explored regional alternatives to address PFAS with Zone 7. Below highlights discussions to date: • Regional PFAS treatment facility —The City and Zone 7 staff explored whether a regional PFAS treatment facility for City Wells 5, 6, and 8 and Zone 7 Chain of Lake (COL) wells could provide construction cost savings due to economy of scale. It was determined that cost savings would not be realized since pumping and pipeline facilities would be required to move water from the OSC to the COL site (and potentially back), and additional property at COL site would need to be purchased to accommodate the combined treatment facility footprint. These additional costs would exceed any economy of scale cost savings. On May 5, 2021, the Zone 7 Board of Page 3 of 4