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Page 2 <br />dĂďůĞϭ͘^ƵŵŵĂƌLJŽĨDƵŶŝĐŝƉĂůtĞůůWƵŵƉŝŶŐĂŶĚ'ƌŽƵŶĚǁĂƚĞƌůĞǀĂƟŽŶƐĂƚdĞƐƚtĞůů^ŝƚĞƐ <br />Over Past Ten Years <br />Year Water Year Type City of Pleasanton <br />Annual Pumping (AF) <br />Total Municipal <br />Pumping (AF) <br />Test Well Spring/Fall <br />'t;ŌŵƐůͿ <br />2015 ƌŝƟĐĂů 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 ƌŝƟĐĂů 3,802 23,597 260-275/250-255 <br />2022 ƌŝƟĐĂů 2,587 21,497 265-270/245-255 <br />2023 Wet 270 9,987 <br />2024 Above Normal 0 7,104 <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 />dĂďůĞϮ͘^ƵŵŵĂƌLJŽĨdĞƐƚtĞůů^ŝƚĞƐƌŝƟĐĂůzĞĂƌĞƉƚŚƚŽtĂƚĞƌ <br />Well <br />ĞƉƚŚƚŽ <br />Top of <br />Screen <br />,ŝŐŚdt <br />;ŌďŐƐͿ <br />Low <br />dt <br />;ŌďŐƐͿ <br />Maximum <br />Available <br />ƌĂǁĚŽǁŶ;ŌͿ <br />Minimum Available <br />ƌĂǁĚŽǁŶ;ŌͿ <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 groundwater pumping (since at least <br />1974) and relatively high City of Pleasanton groundwater pumping (2,600 to 3,800 AFY vs. long-term <br />average of 3,100 AFY). Thus, the well capacity analysis assumes that groundwater pumping at the test <br />well sites is occurring in addition to maximum historical municipal pumping (since at least 1974), which is <br />likely a very conservative assumption for this assessment (i.e., the new test well sites are expected to <br />supplement and be used in conjunction with existing municipal well sites, and not constitute additional <br />pumping at a time of maximum pumping of existing municipal production wells). <br />DĞƚŚŽĚŽůŽŐLJ <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 <br />decline decreases dramatically after about 24 hours for most high-capacity wells. Given the planned long- <br />term continuous operation of the new wells, 30-day and 90-day specific capacity values were evaluated