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A 5 S O C I A T E S I N C , according to the Unified Soil Classification System. Descriptions of soil types encountered and sample collection intervals are presented on the boring logs contained in Appendix A. 3.2.1 Soil Sampling Each soil sample was field screened with a PID for the presence of volatile organic compounds. No petroleum hydrocarbons were observed during field activities in borings SBI through SB4 to depths of 11 feet bgs, the maximum depth explored. The PID readings from each boring were consistently at 0 parts per million (ppm). Sample tubes were sealed at each end using Teflon tape and plastic end caps, labeled, and placed on ice. Soil samples were placed on ice and submitted with chain-of-custody documentation to Sequoia Analytical for laboratory analysis. Copies of field notes are contained in Appendix B. ' 3.2.2 Groundwater Sampling One groundwater sample was collected from each boring at the depth groundwater was first encountered, approximately 10 feet bgs. A GeoprobeO Screen Point 15 Groundwater Sampler was threaded onto the leading end of the Geoprobe after groundwater had been encountered. When the sampler was advanced, O-ring seals and an expendable drive point provided a ! watertight system to ensure sample integrity. ' When the tool was advanced to the desired depth, extension rods were sent downhole to brace the bottom of the sample screen as the tool casing was retracted. When the casing was retracted, approximately 41-inches of screen with slot sizes of 0.004 inches was exposed. Teflon tubing j, with a check valve attached to one end was inserted down the casing until it was immersed in groundwater. Water was then pumped through the tubing and to the ground surface by ' oscillating the tubing up and down. Groundwater samples were placed on ice and submitted with chain-of-custody documentation to Sequoia Analytical for laboratory analysis. Following soil and groundwater sample collection, the borings were backfilled with neat cement grout to the ground surface. ' 3,2.3 Soil and Groundwater Sample Analysis Selected soil and groundwater samples were analyzed by Sequoia Analytical for TPHd, TPHg, BTEX, and oxygenate fuel additives. The analytical results for soil samples are summarized in Table I and the analytical results for groundwater samples are summarized in Table 2. Laboratory data sheets and chain-of-custody documentation are included in Appendix C. wA822541sumrptdoc 4