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CONCLUSIONS <br /> Based on the method and assumptions described, the result of the nitrate loading <br /> estimate indicates that the proposed development on the Site has the potential to cause <br /> a buildup of nitrates in the aquifer of up to 9.7 mg/L-N for a four-bedroom house, 10.7 <br /> mg/L-N for a five-bedroom house, or 11.6 mg/L-N for a six-bedroom house. The results <br /> for a five- or six-bedroom house exceed the drinking water standard of 10 mg/L-N. <br /> The depth of ground water based on recent aquifer levels is estimated to be 32 to 40 <br /> feet below ground surface. The ground-water flow is to the north or northeast at a rate <br /> of approximately seven to ten feet per mile, depending on the season. <br /> A water sample was collected from the main domestic well on the Site. Nitrate was <br /> detected in the sample at a concentration of 4.1 mg/L-N, well below the MCL of 10 <br /> mg/L-N. DBCP was not detected in the water sample. <br /> Live Oak reviewed maps of water test results for nitrate and DBCP compiled by the San <br /> Joaquin County Environmental Health Department (2019). According to the maps <br /> reviewed, ground-water concentrations of nitrate within one-half mile of the Site appear <br /> to be below the MCL; DBCP does not appear to be a problem in the area. <br /> Based on conservative nature of the nitrate loading calculation, clay soil present in the <br /> area, and lack of existing nitrate impacts in the area, the actual nitrate impact to the <br /> ground water from the proposed development may be less than predicted. Recent San <br /> Joaquin County Environmental Health Department policy has been to evaluate each <br /> project on a case-by-case basis to determine whether additional measures to mitigate <br /> nitrate should be employed. <br /> LOGE 20-21 Page 11 <br />