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L f Soil samples were collected from five soil borings drilled around the previous sample location #4, as shown on Figure 3. One boring (SB5) was placed in approximately the same location as sample location #4, and the other four borings (SBI through SB4) were located surrounding boring SB5. The borings were installed with a low-clearance portable, Simco 2400 drill rig using 5-inch diameter hollow stem augers. Each boring was advanced to auger refusal which was between 27 and 30 feet bgs. Groundwater was not encountered in any of the borings. Cuttings and samples were field screened for volatile organic compounds using an organic vapor analyzer (OVA). A small portion of soil from each sampling interval was placed in a clean resealable ziplock bag, allowed to set a minimum of 5 minutes for any VOCs to volatilize, and then screened with the OVA. Results of the OVA field screening were noted on the boring logs which are included as Appendix B of this report.- A total of 23 soil samples were collected from the five soil borings beginning at 15 feet bgs and at 5 foot intervals thereafter. For a detailed description of soil sampling procedures refer to Appendix A. Seventeen of the 23 samples were analyzed as follows: • Total Petroleum Hydrocarbons as diesel TPH-D) by EPA Method 8015m (laboratory detection limits less than 2 mg/Kg). ' Benzene, Toluene, Ethylbenzene and Xylenes (BTEX) by EPA Method 8020 (laboratory detection limits less than 0.003 mg/Kg). Soil samples were submitted for chemical analysis from depths of 15, 20 and 25 feet bgs from borings SBI, SB2, SB4 and SB5. Moderate petroleum odors were encountered in native soil L at 4 feet bgs in boring SB3 and consequently, samples from 5, 15, and 20 feet bgs were submitted for chemical analysis from this boring. Two field duplicate soil samples (SB3-5'Dup and SB5-15'Dup) were analyzed to provide QA. The remaining deep samples were temporarily archived at the laboratory for potential analysis later, however, analytical results indicated that it was not necessary to analyze these samples. 4.0 ANALYTICAL RESULTS L The analytical results for the soil samples collected during this investigation are summarized in Table I. The complete laboratory analytical reports are presented in Appendix C. As shown on Table 1, all of the soil samples analyzed during this investigation did not contain detectable concentrations of TPH-D or BTEX except for SB3-5'Dup. TPH-D concentrations were detected in this duplicate sample at 310 mg/Kg which was inconsistent with the non-detect results found in the primary sample SB3-5'. Both samples were collected from soil which contained approximately 40% clay and from within the same 1-foot interval (5.5 to 6.5 feet bgs). Both samples (SB3-5' and SB3-5'Dup) were re-extracted and re-analyzed. No extractable hydrocarbons were detected during the re-analysis in either sample. The different results for the original analysis and re-analysis are attributed to sample variability. This variability in results within the same sample can be attributed to differential adsorption of the hydrocarbons to the clay particles, however, if there is 310 mg/Kg in soil in this area, it is very limited (less than 6 inches thick) in volume and extent. LMX%APCSWYPONDC.WP 5 03/_794