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BACKGROUND The City of Pleasanton (City) owns and operates three well facilities: Well 5, Well 6, and Well 8. These facilities are utilized to pump the city's annual groundwater alIotmentof 1,140 million gallons, which is approximately 20 percent of the City's water supply; the remaining approximately 80 percent of the city's water supply is purchased from the Zone 7 Water Agency (Zone 7). The City typically requires simultaneous operation of two of its three well facilities, in combination with Zone 7 supply, to meet demands during peak periods. The third well facility provides redundancy in the event of facility outages. The City's well facilities are reaching the end of their useful lives and require rehabilitation and/or replacement. Additionally, groundwater monitoring has found the presence of per- and polyfluoroalkyl substances (PFAS) in all three well facilities. PFAS are unregulated contaminants of emerging concern in drinking waterdue to theirhealth impacts and tendencyto accumulate in groundwater. Perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are the most studied substances and are the focus of initial regulatory efforts in California. The State Water Resources Control Board Division of Drinking Water (DDW) intends to regulate PFOA and PFOS by establishing maximum contaminant levels (MCLs) as early as 2024. DDW has not yet indicated the duration of any compliance windows after issuing MCLs. DDW has also started the process of reviewing other PFAS for possible regulation, buta schedule for implementation has notyet been clearly identified. At the City Council meeting on June 15, 2021, City Council authorized staff to proceed with final design forthe PFAS Treatment and Wells Rehabilitation Project. The goal of the project is to implement PFAS treatment and rehabilitate and/or replace the City's well facilities to extend theiruseful lives as reliable, locally controlled sources of water. The project includes the elements described below: • Rehabilitate the existing Well 8 facility and restore its original pumping capacity of 3,500 gallons per minute (gpm) • Constructa new Well 9 facility located in Amador Valley Community Park with a capacity of 2,300 gpm. Well 9 would replace the existing Well 5 facility • Rehabilitate the existing Well 6 facility (to be renamed Well 10) including construction of a newwell casing. The facilitywould maintain its existing pumping capacity of 2,300 gpm • Constructa centralized treatment facility (CTF) for disinfection, fluoridation, and PFAS treatment of the city's groundwater prior to distribution. The CTF would be designed for an ultimate capacity of 8,100 gpm • Install approximately 5,200 feet of piping to convey raw groundwaterfrom the well facilities to the CTF • Replace and upsize 1,600 feet of treated water distribution main along Santa Rita Road to allow the treated groundwaterto be distributed from a centralized location. The estimated cost for the project is $46 million. The cost estimate was last prepared in June2021 and is currently being u pdated to reflect cu rrent economic conditions. It is anticipated that the cost estimate will increase due to recent inflation trends. At the City Council Meeting on November 16, 2021, City Council authorized staff to apply fora Drinking Water State Revolving Fund (DWSRF)loan from the State Water Resource Control Board (SWRCB)to help fund the project. To date, the general, technical and environmental applications have been submitted, while the financial application has not Page 2 of 3