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Dykxhoorn Page 4 of 9 <br /> Project Number: E07024B <br /> Date: October 31, 2007 <br /> 4.4 Water Sample Constituents <br /> The water sample was analyzed for nitrate and' DBCP. Nitrate was fou at 28 mg/ NO3; <br /> below the maximum contaminant level (MCL) set by the US EPA. DBCP was detein the <br /> sample. The analytical reports prepared by FGL Environmental can be found in ppendix of <br /> this report. <br /> The presence of nitrates is not uncommon in shallow ground water aquifers in San Joaquin <br /> County and other parts of the Central Valley. Nitrate in ground water occurs as a result of the <br /> application of fertilizers, livestock waste, and untreated septic tank waste. Nitrate is mobile and <br /> often accumulates in the shallow ground water zones. <br /> In the early 1900s, natural levels of nitrate in ground water were measured in forty-three (43) <br /> wells throughout the Sacramento Valley by Bryan (1923). It was thought that ground water at <br /> that time was close to "natural" conditions. Based on the work by Bryan, it is estimated thy" <br /> under"natural" conditions, ground water concentration containing nitrate is no more then about <br /> 13.5 mg/L-NO3 (3 mg/L-N). Areas having 24.75 mg/L-NO3 (5.5 mg/L-N) or more are those in <br /> which nitrate concentrations may be increasing (Hull, 1984). <br /> DBCP was not found in the sample. DBCP is a nematocide and soil fumigant for vegetables and <br /> grapes. It is thought to cause health problems consisting of kidney damage, liver damage, and <br /> cancer. The use of DBCP was discontinued in 1979. The Environmental Protection Agency <br /> (EPA) set the maximum contaminant limit (MCL) at 0.2 parts per billion (ppb) because the EPA / <br /> believes that given present technology and resources, this is the lowest level to which water <br /> systems can reasonably be required to remove this contaminant should it occur in drinking <br /> water. <br /> 4.5 Well Water Sample Collection, Handling, and Transportation <br /> The sample for nitrate was collected in a clean plastic container; the sample for DBCP was <br /> collected in two clean glass vials. The samples were then transported on ice and remanded <br /> under chain of custody to FGL Environmental, Stockton. <br /> 4.6 Chain of Custody <br /> The Chain of Custody document has been included in the appendix of this report. <br /> 5.0 SOIL PROFILE AND GEOLOGIC INFORMATION <br /> The Site is depicted on the Geologic Maps of the Sacramento-Sanodeposi <br /> s within the <br /> Quaternary Modesto Formation and Quaternary Riverbank FormatioQuaternary <br /> Modesto Formation (undifferentiated) is unit of undifferentiated alluinly arkosic, <br /> forming the toe of the Mokelumne alluvial fan, generally coveredof Holocene <br /> intertidal deposits. <br /> 902 Industrial Way•Lodi,CA 95240•209.367.3701 •Fax 209.369.4228 ©2007 Neil O.Anderson&Associates,Inc <br />