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On-Site Wells One domestic well is 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 Live Oak collected a water sample from the domestic well on the Site on March 18, 2019. The sample was analyzed for nitrate and dibromochloropropane (DBCP) per San Joaquin County Environmental Health Department policy. Additional water samples were collected on April 1 and April 10, 2019; these samples were analyzed for nitrate. The additional sampling was conducted because Mr. Kumar indicated the domestic well has been largely unused for several years. For the March 18 sample, the well was pumped for five minutes per the sampling protocol. Live Oak felt that additional pumping should take place since the well has been unused for such a long time. After pumping for several hours, the second water sample was collected on April 1; after a second round of pumping, the third sample was collected on April 10. As required by the laboratory, the samples were collected in plastic containers and two glass vials for nitrate and DBCP analysis, respectively. Trip blanks were also utilized for the DBCP analysis. The samples were placed on ice and transported under chain of custody to FGL Environmental, Stockton. Nitrate was detected in the March 18 sample at a concentration of 11.5 mg/L-N. DBCP was not detected in the water sample. Nitrate was detected in the April 1 and 10 samples at a concentration of 10.5 mg/L-N. 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. 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 syndrome, which results in reduced oxygen supply to vital tissues. Pregnant women and certain others can also develop methemoglobinemia. Symptoms include a bluish LOGE 1909 Page 4