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Water Sample <br /> Live Oak collected a water sample from the domestic well on the Site on September 27, <br /> 2022. The sample was analyzed for nitrate and dibromochloropropane (DBCP) per San <br /> Joaquin County Environmental Health Department policy. <br /> As required by the laboratory, the sample was collected in a plastic container and three <br /> glass vials for nitrate and DBCP analysis, respectively. Trip blanks were also utilized. <br /> The sample was placed on ice and transported under chain of custody to FGL <br /> Environmental, Stockton. <br /> Nitrate was detected in the water sample at a concentration of 4.0 mg/L-N. DBCP was <br /> not detected in the sample. The laboratory analytical results are attached as Appendix 5 <br /> of this report. <br /> Nitrate is commonly detected in shallow ground water aquifers of the Central Valley. <br /> Application of fertilizers, livestock waste, and untreated septic tank waste can all <br /> contribute to nitrate in ground water. Nitrate is mobile and tends to accumulate in shallow <br /> ground water zones. Based on work in the Sacramento Valley from the early 1900s, it is <br /> estimated that under "natural" conditions, ground water contains nitrate at concentrations <br /> no more then about 3 mg/L-N. Nitrate may be increasing in areas with concentrations of <br /> 5.5 mg/L-N or more (Hull, 1984). The US EPA has set the Maximum Contaminant Level <br /> (MCL) for nitrate at 10 mg/L-N. <br /> Although nitrate is a naturally-occurring compound necessary for plant growth, it can <br /> cause health problems when present at high levels in drinking water. The most common <br /> health effect of nitrates in water is methemoglobinemia, or blue baby syndrome, which <br /> results in reduced oxygen supply to vital tissues. Pregnant women and certain others <br /> can also develop methemoglobinemia. Symptoms include a bluish color of the skin, as <br /> well as headache, dizziness, weakness, and difficulty breathing. Ingestion of high levels <br /> of nitrates over time can also lead to gastric problems. <br /> DBCP is a nematocide and soil fumigant for vegetables and grapes. It is known to cause <br /> male reproductive effects and is classified as a probable human carcinogen. Most <br /> domestic use of DBCP was discontinued in 1977 through 1979. The US EPA set the MCL <br /> at 0.2 parts per billion (ppb, equivalent to µg/L) because it believes that given present <br /> technology and resources, this is the lowest level to which water systems can reasonably <br /> be required to remove this contaminant should it occur in drinking water. The Maximum <br /> Contaminant Level Goal (MCLG) for DBCP is zero. <br /> Soil Profile and Geologic Information <br /> The Site is depicted on the Preliminary Geologic Map of the Lodi 30' x 60' Quadrangle, <br /> California (Dawson, 2009). The Site is depicted within a map unit of the Riverbank <br /> LOGE 2245 Page 4 <br />