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Section 2: Water Supply Options and Alternatives Water Supply Alternatives Study 2-3 DRAFT for review purposes only. Use of contents on this sheet is subject to the limitations specified at the end of this document. Water Supply Alternatives Study-Draft Report.docx 2.2 Alternatives for Evaluation The initial screening resulted in identifying four alternatives for further consideration: •Alternative 1 – Baseline Project (PFAS Treatment and Wells 5, 6, & 8 Rehabilitation) •Alternative 2 – Reduced Baseline (PFAS Treatment for Well 8 only) •Alternative 3 – Two New City Wells (West of PFAS plume) •Alternative 4 – 100% purchases from Zone 7 To meet peak demand requirements, alternatives may require infrastructure improvements, such as booster pumps, pipelines, and/or a new turnout from Zone 7’s transmission system. Infrastructure improvements for each alternative were identified through Akel’s Water Supply Alternative Improvements summary dated August 2, 2023, and provided in Appendix E. Some near-term infrastructure improvements are required to accommodate future demands regardless of the alternative that moves forward. This Study assumes that the City will fund and address these near- term improvements (including pipelines F-1, F-4, and F-5 and baseline booster station BS-1 as identified in Akel’s Water Supply Alternative Improvements summary dated August 2, 2023 [Appendix E], estimated at ~$10.2M) in advance of implementing water supply alternatives. As noted in Section 1.1, Alternative 1 (Baseline Project) involves constructing a centralized treatment facility at the City’s Operations Services Center for PFAS treatment, disinfection, and fluoridation (Figures 2-1 and 2-2). Based on Carollo’s 50 percent design deliverable opinion of probable construction cost, the treatment facility would involve seven treatment trains with two vessels per train and a system peak design flow of 5,800 gallons per minute (gpm), including 3,500 gpm from Well 8 and 2,300 gpm from either Well 9 or Well 10 (Carollo, 2022). Alternative 1 would involve replacing Well 5 with a new Well 9 at Amador Park, rehabilitating Well 6 (renamed Well 10), and rehabilitating Well 8 to restore pumping capacity. This alternative also requires constructing a new raw water transmission pipeline and improvements to treated water distribution piping.