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Section 2: Water Supply Options and Alternatives Water Supply Alternatives Study 2-2 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 In coordination with City staff, BC performed initial screening of the water supply options, as summarized in Table 2-2. To pass initial screening, options needed to meet the annual yield of 3,500 AFY and show early potential for reducing costs compared to the baseline project. Further details on the screening process are included in Appendix A. Table 2-2. Results of Initial Screening of Potential Water Supply Options Category Option Is there potential for lower cost/increased benefit compared to Baseline Project? Does the option pass an initial screening for technical and institutional feasibility “fatal flaws”? Baseline Project PFAS Treatment and Wells 5, 6, & 8 Rehabilitation Project Not applicable Yes Modified PFAS Treatment (Well 8)Yes Yes New City well(s) outside PFAS plume (west part of the City)Yes Yes Zone 7 pump on City’s behalf Yes No – This concept was initially screened out due to Zone 7’s anticipated timing for updating its regional groundwater model and Well Siting Master Plan. Zone 7 subsequently decided to accelerate its planning, which makes a joint project potentially viable. The City and Zone 7 will continue to explore this option as Zone 7 progresses its planning. Regional PFAS Treatment Facility (at Pleasanton’s Operations Services Center) Yes No – Zone 7 is not interested in advancing this concept. Groundwater Supply Options Blending/Dilution No No – Based on mass balance calculations, dilution would require substantially more supply from Zone 7 than is available or capable of being delivered to the City. 100% purchases from Zone 7 Maybe Yes Purchases from another agency No No – Connections to San Francisco Public Utilities Commission or East Bay Municipal Utility District do not currently exist and are not institutionally feasible. Long-term transfers through Zone 7’s system are considered under the option for 100% purchases from Zone 7. Other Supply Sources Local alternative supplies No No – High cost of desalination or satellite treatment relative to baseline and seasonality/unpredictability of stormwater availability Expansion of non-potable system No No – Recycled water is supply-limited in the peak season, which is when the City typically relies on groundwater for meeting peak potable demands. Demand Management Long-term WUE No Yes – While WUE alone cannot reduce the City’s peak demand and annual need for 3,500 AFY within the timeframe desired by the City, WUE is considered an “add-on” that complements all other water supply options.