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Given that the ground elevation of the Site is approximately 48 feet above mean sea level, the depth to water below the Site is estimated to be approximately 58 to 63 feet. 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 (Plates 6 and 7). According to the nitrate map, six wells within a one-mile radius of the subject Site have been tested for nitrate. Five of these wells were found to contain nitrate at concentrations between 0.1 and 5.0 mg/L-N; the remaining well had a concentration over 10 mg/L-N. According to the DBCP map, seven wells within a one-mile radius of the Site have been tested for DBCP. DBCP was detected in three of the wells at concentrations between 0.01 and 0.2 g/L; it was detected at concentrations over 0.2 !Ag/L in the remaining four wells. On-Site Wells A domestic well is located on the Site (Plate 2). One well permit was identified for the Site from among the files of the San Joaquin County Environmental Health Department. The permit, dated April 1995, was for a new domestic well approximately 250 feet deep, with a grout seal at 200 feet. An older well was to be destroyed at the same time. This permit has been attached in Appendix 4 of this report. Water Sample Live Oak collected a water sample from the domestic well on the Site on June 16, 2021. The sample was analyzed for nitrate and dibromochloropropane (DBCP) per San Joaquin County Environmental Health Department policy. As required by the laboratory, the sample was collected in a plastic container and two glass vials for nitrate and DBCP analysis, respectively. Trip blanks were also utilized. The sample was placed on ice and transported under chain of custody to FGL Environmental, Stockton. LOGE 2132 Page 3