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