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Maximum Contaminant Level (MCL) set by the US EPA for nitrate is 10 mg/L-N; the MCL for DBCP is 0.2 µg/L. On-Site Wells A domestic well is currently located on the Site. One well permit was identified for the Site from among the files of the San Joaquin County Environmental Health Department. The permit, dated June 1994, is for a new domestic well with a 100-foot grout seal. It .� appears that this well is located to the east of the current Site; an existing well located 1 (� on the Site was also indicated in the permit sketch. This permit has 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 30, 2019. 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. Nitrate was detected in the sample at a concentration of 5.2 mg/L-N. DBCP was(not detected. The laboratory analytical results are attached as Appendix 3 of this report In January 1995, Armstrong Engineering & Development, LTD. performed a Soil Suitability Study for a minor subdivision separating the Site from the adjacent land to the east (Appendix 4). As part of the study, a water sample was collected from the domestic well and analyzed for nitrate and DBCP. At that time, nitrate was detected at 8.8 mg/L-NO3 (equivalent to 1.9 mg/L-N); DBCP was not detected. 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 than 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. Although nitrate is a naturally-occurring compound necessary for plant growth, it can cause health problems when present at high levels in drinking water. The most common health effect of nitrates in water is methemoglobinemia, or blue baby LOGE 1931 Page 4