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Page 2 <br />Table 1. Summary of Municipal Well Pumping and Groundwater ElevaƟons at Test Well Sites <br />Over Past Ten Years1 <br />Year Water Year <br />Type <br />City of Pleasanton <br />Annual Pumping <br />(AF) <br />Total Municipal and <br />Agricultural Pumping <br />(AF)2 <br />Test Well <br />Spring/Fall GWE <br />(Ō msl) <br />2015 CriƟcal 2,775 8,874 265-270/270 <br />2016 Dry 3,752 9,860 <br />2017 Wet 4,222 11,369 <br />2018 Below Normal 3,913 12,657 <br />2019 Wet 3,785 15,309 <br />2020 Dry 2,701 17,069 <br />2021 CriƟcal 3,802 23,597 260-275/250-255 <br />2022 CriƟcal 2,587 21,497 265-270/245-255 <br />2023 Wet 270 9,987 <br />2024 Above Normal 0 7,104 <br />1. Annual pumping derived from Table D-3 in 2024 Water Year Annual Report (Zone 7, March 2025). <br />2. Total Municipal and Agricultural Pumping includes City of Pleasanton pumping. <br />A summary of the proposed top of well screen, high and low depths to (static) water, and calculated <br />available drawdown at each test well site are summarized in Table 2. <br />Table 2. Summary of Test Well Sites CriƟcal Year Depth to Water <br />Well <br />Depth to <br />Top of <br />Screen <br />High DTW <br />(Ō bgs) <br />Low <br />DTW <br />(Ō bgs) <br />Maximum <br />Available <br />Drawdown (Ō) <br />Minimum Available <br />Drawdown (Ō) <br />Tennis 195 16.7 75 178 120 <br />Hansen 298 24.5 75 273.5 223 <br />Del Prado 170 16.7 65 153 105 <br />Notes: DTW = Depth to Water <br />Based on the analysis summarized above, the regional groundwater level conditions assumed for the well <br />capacity analysis are based on a time of maximum overall municipal/agricultural groundwater pumping <br />(since at least 1974) and relatively high City of Pleasanton groundwater pumping (2,600 to 3,800 AFY vs. <br />long-term average of 3,100 AFY). Thus, the well capacity analysis assumes that groundwater pumping at <br />the test well sites is occurring in addition to maximum historical municipal pumping (since at least 1974), <br />which is likely a very conservative assumption for this assessment (i.e., the new test well sites are expected <br />to supplement and be used in conjunction with existing Zone 7 municipal well sites, and not constitute <br />additional pumping at a time of maximum pumping of existing municipal production wells). <br />Methodology <br />The well capacity calculation methodology requires input values for specific capacity, available drawdown, <br />and assumed production well efficiency. Specific capacity varies (declines) with time, although the rate of