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Given that the ground elevation of the Site is approximately 33 to 34 feet above mean sea level, the depth to water below the Site is estimated to be approximately 12 to 16- feet. San Joaquin County experienced its highest recent ground-water levels in 1983 and 1999 (Plates 7 and 8). Maps of ground-water levels were reviewed for this study (San Joaquin County Flood Control and Water Conservation District, 1983 and 1999). The Site is outside the mapped area for 1983; depth to water beneath the Site was approximately 10 feet in 1999. Potential Ground Water Contamination Issues The Soil Suitability Study is not intended to be an investigation into ground-water contamination sources, and no such investigation was conducted. Many sources can contribute to ground water contamination, including leaking underground storage tanks, agricultural activities, dairies, septic systems, and storm water infiltration. Agricultural activities and the use of septic systems in the area are known ground water contamination sources with the potential to impact the Site. Two common ground-water contaminants in San Joaquin County are nitrate and dibromochloropropane (DBCP). Live Oak reviewed the San Joaquin County Environmental Health Department's maps of Nitrate — Land Use Data and DBCP— Land Use Data dated February 20, 2019. According to the maps (Plate 9 and 10), no wells within a half-mile radius of the subject Site have been tested. Six wells within a one- mile radius have been tested for nitrate; it was detected in all six at concentrations greater than 10.0 mg/L-N. One well within a one-mile radius of the Site was tested for DBCP; no DBCP was detected. The Maximum Contaminant Level (MCL) set by the US EPA for nitrate is 10 mg/L-N; the MCL for DBCP is 0.2 ug/L. Seven dairies are located within three-quarters of a mile of the Site; the dairies are likely the cause of the elevated nitrate levels detected in nearby wells; indeed, based on the sample locations and lack of other development in the area, it appears that many of the water samples were collected from wells at the dairies. On-Site Wells No wells are currently located on the Site. No well permits were identified for the Site from among the files of the San Joaquin County Environmental Health Department. Water Sample No water sample was collected as part of this study. LOGE 1914 Page 3