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A A.' "k WDODARR &CURRAN be supplied. The description and analysis shall be based on information that is reasonably available, including, but not limited to, historic use records. (4)A detailed description and analysis of the amount and location of groundwater that is projected to be pumped by the public water system, or the city or county if either is required to comply with this part pursuant to subdivision (b), from any basin from which the proposed project will be supplied. The description and analysis shall be based on information that is reasonably available, including, but not limited to, historic use records. (5)An analysis of the sufficiency of the groundwater from the basin or basins from which the proposed project will be supplied to meet the projected water demand associated with the proposed project.A water supply assessment shall not be required to include the information required by this paragraph if the public water system determines, as part of the review required by paragraph(1), that the sufficiency of groundwater necessary to meet the initial and projected water demand associated with the project was addressed in the description and analysis required by subparagraph (D)of paragraph (4)of subdivision (b) of Section 10631. In addition to the SSJID supply, the City owns and operates a total of five groundwater production wells within the Tracy Subbasin (Wells 6, 7, 8, 9, and 10),which produce the majority of the City's water supply. These five wells are listed in Table 6 along with their existing maximum pumping capacity. Each is located within the City, east of 1-5, as shown in Figure 5. Groundwater from these wells is treated to remove arsenic at the Louise Avenue Water Treatment Facility(LAWTF),which came online in 2012.As shown,the combined maximum pumping capacity of Wells 6 through 10 is 7,250 gallons per minute(gpm),although this is limited by the treatment capacity of the LAWTF(6,250 gpm). For the purposes of this evaluation, it is assumed that the City's wells are pumped at 50 percent of their maximum capacity on an annual basis. Given this supply assumption,the City's current annual groundwater supply capacity is equivalent to approximately 5,850 AFY if all five wells were in service.As explained below,Well 9 is currently offline,which reduces the groundwater supply to approximately 4,720 AFY. The City currently has no plans to increase production at their active wells to account for Well 9 production loss. The City owns an additional well(Well 21)that includes a treatment facility(Well 21 Water Treatment Facility)designed for disinfection and manganese treatment. Well 21 has remained inactive since 2013 due to sanding in the well and elevated levels of arsenic and uranium. Well 21 is also above the response level (RL) for per- and polyfluoroalkyl substances(PFAS), and the City is working to relocate the well and provide improvements to bring it back on-line.The City has begun engineering design for the replacement of Well 21 and Well 21 Water Treatment Facility. In addition, since the publication of the 2015 UWMP, Well 9 was also taken offline due to elevated PFAS above the RL.The City is investigating alternatives to bring this well back online such that the drinking water will be below the RL for PFAS. Potential options include conducting well profiling at Well 9 to evaluate potential modifications, relocating Well 9 to address PFAS and other constituents of concern (CDCs), and providing treatment at the Louise Avenue Water Treatment Facility or Well 21 Water Treatment Facility. The option to provide PFAS treatment for Well 9 at the Well 21 Water Treatment Facility would remove limitation for groundwater production based on LAWTF treatment capacity. Because Wells 9 and 21 are currently offline,the Current Well Capacity estimate in Table 6 does not include production from these two wells. Califia(0011533.00) 14 Woodard&Curran, Inc. River Islands Phase 2 Development Water Supply Assessment September 2020