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DBCP map, two wells within a one-mile radius of the Site have been tested for DBCP. No DBCP was detected in the first well; it was detected at a concentration over 0.2 ug/L in the second well. On-Site Wells Two domestic wells and two irrigation wells are located on the Site. The San Joaquin County Environmental Health Department well permit files were searched for the Site address. Four permits were identified: • November 1991 permit for pump installation at domestic well. The permit indicates a depth of 200 feet to the grout seal and notes that an old well was destroyed (3592). • December 1998 permit for pump repair at well (3592). • January 1978 permit for pump repair at well (3434). • July 1995 permit for new irrigation well with a grout seal at 50 feet (3434). These permits have been included in Appendix 4 of this report. Water Sample Live Oak collected a water sample from the domestic well at 3592 West Sargent on September 21, 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 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. Neither nitrate nor DBCP was detected in the water sample. The laboratory analytical reports 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 2151 Page 4