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Ali soil samples were analyzed for the following parameters: <br /> o Organochlorine Pesticides EPA Method 8080 <br /> o Organophosphoroiis Pesticides EPA Method 8140 <br /> o Carbamates Method 632 Modified. <br /> A]_] water samples were analyzed for the following parameters- <br /> 0 Organochlorine Pesticides EPA Method 608 <br /> o Organophosphorous Pesticides EPA Method 614 <br /> o Chlorinated Phenoxy Acid Herbicides SM 509B <br /> a Carbamate Pesticides EPA Method 632 <br /> (% Triazi.ne _Herb.l.c_Ldes EPA Method 619 <br /> A summary of the analytical results for soil and water is pre- <br /> sented in `Fables 2 and 3 respectively and all laboratory reports <br /> n their entirety az-e presented in Appendices B and C. <br /> A.5. 1 Interpretation of Soil Sample Results <br /> As shown on Table 2 , all but one borehole soil sample (BC-5) <br /> contained detectable concentrations of one or more of the chemi- <br /> Gals for which the analyses were conducted. <br /> To compare the chemical concentrations found to regulatory agencyt <br /> criteria, Table 2 includes entries from published regulatory <br /> -' standards. The standards utilized for the comparison purposes A . <br /> are as follows: <br /> o California Department of Health Services (DOHS) Total <br /> Threshold .Limit Concentration (TTLC) <br /> c, Regional Water Quality Control Board (RWQCB) designated y <br /> levels (DL) for allowable chemical concentrations in a solid <br /> for the protection of. groundwater. <br /> When compared to these standards, only the samples collected from <br /> four boreholes (BA, BC, BG and BH) contained concentration of <br /> pesticide compounds in excess of current regulatory criteria. <br /> The only compounds found above regulatory criteria were from the <br /> DDT family of chemicals (DDT, DDE and DDD) . As an aid to inter- <br /> pretation, Figure 4 presents the total DDT compound concentra- <br /> tions (DDT + DDD + DUE) as found at each borehole location. <br /> At borehole BA, while the concentrations detected were below the <br /> TI'LC value of 1 mu/Kg, the soil samples collected from all three ;.,; . <br /> depths (11 , 3 ' and 51 ) contained concentrations of 4 , 4-DDT in <br /> excess of the DL, which for this compound is 240 ng/Kg. <br /> '- For borehole BC, 4 , 4-DDT and 4 ,4-DDE were only detected in the 1' <br /> and 3 ' samples. The concentrations observed in the sample <br /> collected from the 1 ' depth exceeded both the DL and the TTLC <br /> - 7 - <br />