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As required by the laboratory, the sample was collected in a plastic container and two glass vials for nitrate and DBCP analysis, respectively. A trip blank was also utilized. The sample was placed on ice and transported under chain of custody to FGL Environmental, Stockton. Results of the tests are forthcoming. Qr/,77r� 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 Geologic Information The Site is depicted on the boundary of two geologic maps in an area without detailed mapping. To the north of the site the geology is mapped and shown on a map titled Preliminary Geologic map of Cenozoic Deposits of the Bellota Quadrangle, California (Marchand and Atwater, 1979). Geologic mapping located to the west of the site is titled Geologic Maps of the Sacramento — San Joaquin Delta by Atwater (1982). Based on these maps and experience in the area, the site is located within alluvial deposits of the Pleistocene age upper member of the Modesto Formation and Alluvium of the Calaveras River and vicinity. The Alluvium of Calaveras River and vicinity is a bundled or combined grouping of the Modesto Formation on Marchand and Atwater's map. Both of these mapped units which exist at the site consist of arkosic alluvium forming river terraces and alluvial fans. It is composed of sand, silt, and clay mixtures, with minor gravel, probably glacial outwash (Plate 9). The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of Hollenbeck silty clay, 0 to 2 percent slopes (Plate 10) (USDA, 2009). The table below presents some selected properties of this soil: LOGE0914 Page 4