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:,`i1/NC. Site, one equipment blank was collected from drilling equipment between boreholes at the Site to demonstrate the adequacy of decontamination procedures, and one blank was collected from sampling equipment prior to sampling at the Site. 2.6 Subsurface Conditions Subsurface conditions from 6.5 to 8.5 feet below ground surface bgs consisted typically of moist, dark to pale yellow-brown silty sand. In boreholes BH-7 and BH-8, north of the property boundary, pale yellow-brown sand with few fines was observed from the surface to a depth of nine feet bgs. Groundwater was encountered from depths of 23 to 27 feet bgs. 2.7 Soil Sampling and Analytical Results During the drilling activities, one soil sample was collected at a depth of seven feet bgs from each borehole. A portion of the sample was retained for headspace analysis and descriptive logging according to the Unified Soil Classification System (ASTM D-2487). The locations of the boreholes are shown in Figure 2. One soil sample from each borehole was submitted to Excelchem Environmental Laboratories (Excelchem), California Department of Health Services Certification No. 2119, for analysis for volatile organic compounds (VOCs) using EPA Method 8240. Volatile organic compounds were not detected in the soil samples. The analytical results for the soil samples are summarized in Table 1, and a copy of the laboratory analytical results and project chain-of-custody documents are included in Appendix E. 2.8 Groundwater Sampling and Analytical Results Each of the six boreholes was extended approximately five feet into groundwater and a groundwater grab sample was collected through the center of the drilling rod. Samples were decanted into in EPA-approved containers and submitted to Excelchem for analysis for VOCs by EPA Method 624. Volatile organic compounds were not detected in groundwater by the analytical testing, with the exception of low concentrations of ethylbenzene and xylene in borehole BH-10. These compounds are constituents normally associated with petroleum hydrocarbons. In addition, constituents of concern were not detected in equipment blanks collected at the Site, indicating that cross-contamination did not occur. The analytical results for the groundwater samples are summarized in Table 1, and a complete copy of the laboratory analytical results and project chain-of-custody documents are included in Appendix E. HABOFATHASEM]UPONWPON28.DFT 4