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Water Sample Live Oak collected a water sample from the domestic well on the Site on October 18, ( 3� 2010. The sample was to be analyzed for nitrate and dibromochloropropane (DBCP) 6(_0per 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 DBCPana is, respectively. A trip blank was also utilized. The sample was placed ice and transported chain of custody to FGL Environmental, Stockton Results of the tests are forthco 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 13.5 mg/L-NO3 (3 mg/L-N). Nitrate may be increasing in areas with concentrations of 24.75 mg/L-NO3 (5.5 mg/L-N) or more (Hull, 1984). DBCP is a nematocide and soil fumigant for vegetables and grapes. It is known to cause male reproductive effects and is classified as a probable human carcinogen. Most domestic use of DBCP was discontinued in 1977 through 1979. The US EPA set the MCL at 0.2 parts per billion (ppb) because it believes that given present technology and resources, this is the lowest level to which water systems can reasonably be required to remove this contaminant should it occur in drinking water. The Maximum Contaminant Level Goal (MCLG) for DBCP is zero. Soil Profile and Geoloaic_informatiion The Site is depicted on the Preliminary.geologic map showing Quatemary deposits of the Lodi Quadrangle, California (Marchand and Atwater, 1979). The Site is depicted -primarily within the- Riverbank Formation .middle unit, described as "arkosic alluvium forming Mokelumne River terraces and alluvial fan; chiefly sand; probably glacial outwash." Portions of the Site also fall within the Riverbank Formation upper unit, described as "foothilkderived alluvial sand and silt; contains abundant volcanic detritus." Holocene alluvium, described as channel, levee, and floodplain deposits; chiefly sift and clay with fine sand along principal drainageways," is present along the north side of the Site (Plate 7). The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of San Joaquin complex, with small areas of Sailboat silt loam and Bruella sandy loam (Plate 8) (USDA, 2009). The table below presents some selected properties of these soils. LOGE1024 Page 4