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1 <br />' Results of the soil analyses showed that petroleum hydrocarbons and VOCs were detected <br /> in only one soil sample (boring MW-1 at 11 to 11 5 feet BGS) Petroleum hydrocarbons <br /> quantified as hydraulic oil and as mineral spirits were detected in this sample at <br /> concentrations of 22,300 and 840 mg/kg, respectively Low concentrations (from 0 001 <br /> to 0 113 mg/kg) of seven VOCs were also detected in the sample The remaining nine soil <br /> samples did not contain detectable amounts of TPH or VOCs Results of soil analyses are <br /> presented in Appendix A and summarized in Table 1 The results of the groundwater <br /> analyses are presented in Appendix B and summarized in Table 2 <br />' The initial groundwater sample was collected from MW-1 on November 21, 1994 At the <br /> request of the SJCPHS, well MW-1 was resampled in June 1995 The groundwater <br /> 1 samples collected for the retesting were tested for TPH by USEPA method 8015 and <br /> VOCs by USEPA method 8260 <br />' The results of the initial groundwater analyses showed that, except for 14 micrograms per <br /> liter (pg/L) chloroform, no petroleum hydrocarbons or VOCs were detected The absence <br /> of chloroform from the soil samples suggests that the chloroform might have been <br />' introduced during the development of the well, for which municipally chlorinated water <br /> was used Its absence In the subsequent analyses confirms that it is not characteristic of <br /> this groundwater <br />' At the request of the SJCPHS, a second groundwater sample was collected on June 22, <br /> 1995 As with the initial sample, no TPH was detected However, low levels (1 0 to <br /> 2 6 pg/L) of 13 VOCs were detected m this sample Because this was not consistent with <br /> the initial groundwater results, a confirmatory sample was collected on June 27, 1995, and <br /> analyzed by the same laboratory No VOCs were detected in the June 27, 1995, sample <br />' The results of the laboratory QC presented u1 Appendix B (1 e , method blank, surrogate <br /> recoveries, matrix spike, and matrix spike duplicate samples) for both samples tested in <br /> June show the data are of acceptable quality The results of the first and third rounds of <br />' sampling agree, and field and laboratory quality control (QC) results show that the third <br /> sampling event contained no field- or laboratory-introduced contamination This suggests <br /> that the samples collected during the second round of sampling might have become <br /> contaminated either during sample collection or before their analysis The results from the <br /> second groundwater sampling event (Appendix B) are therefore considered suspect, and <br />' are not included in Table 2 <br />' 1.3 Baseline Conditions <br /> The sediments encountered in borings B-1 and MW-1 are predominantly sands (with clay, <br /> ' silt, or gravel) Boring MW-1 was terminated after encountering clay at a depth of 93 to <br /> 98 feet BGS Depth to groundwater in well MW-1 was approximately 72 feet BGS <br /> during November 1994 The lithology beneath the site is depicted in Figure 3 <br /> 1 <br /> 1 1PJ21RXK00285 DOC-951jlc 1 Rev 0 8/28/95 <br /> 22074-001 001 1-2 <br />