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Use Data dated February 20, 2019 (Plates 6 and 7). According to the nitrate map, three wells within a one -mile radius of the subject Site have been tested for nitrate. Nitrate was detected at a concentration between 0.1 and 5.0 mg/L-N in one of the wells, and at concentrations between 5.1 and 10 mg/L-N in the other two wells. According to the DBCP map, two wells within a one -mile radius of the Site have been tested for DBCP. DBCP was not detected in either well. On -Site Wells A domestic well is located on the Site (Plate 3). Two documents related to the well were identified for the Site from among the files of the San Joaquin County Environmental Health Department: • October 2019 well completion report. The well was completed to a total depth of 320 feet, and the static water level was reported as 130 feet. • October 2019 permit for the above new well. These permits have been included in Appendix 4 of this report. Water Sample Live Oak collected a water sample from the domestic well on the Site on May 2, 2022. 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 three 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. Nitrate was detected in the water sample at a concentration of 1.4 mg/L-N. DBCP was not detected in the sample. The laboratory analytical results are attached as Appendix 5 of this report. Nitrate is commonly detected in shallow ground water aquifers of the Central Valley. Application of fertilizers, livestock waste, and untreated septic tank waste can all contribute to nitrate in ground water. Nitrate is mobile and tends to accumulate in shallow ground water zones. Based on work in the Sacramento Valley from the early 1900s, it is estimated that under "natural" conditions, ground water contains nitrate at concentrations no more then about 3 mg/L-N. Nitrate may be increasing in areas with concentrations of 5.5 mg/L-N or more (Hull, 1984). The US EPA has set the Maximum Contaminant Level (MCL) for nitrate at 10 mg/L-N. LOGE 2226 Page 4