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liner. Following extraction from the Macro-Core Sampler, core tubes were typically cut in half, capped, labeled and temporarily stored in an ice-cooled chest. A lithologic log was prepared during drilling based on examination of the soil cores and utilizing the Unified Soil Classification System and generally accepted geologic interpretive descriptions (Appendix A). Soil cores were visually examined for the presence of staining, discoloration, or odors indicative of petroleum hydrocarbon contamination and these observations were recorded on the lithologic log (Appendix A). Weak product odor was detected in core samples collected in boring B5-1 within the interval from about 14 to 25 feet bgs. Selected soil samples within this interval were transferred to a clean plastic bag that was sealed for subsequent headspace screening using a photoionization detector (PID). The PID was also used to monitor ambient air in the breathing zone around the boring and was used to periodically screen for volatile - ionizable organics inside the open borehole. The PID values were recorded on the lithologic log (Appendix A). After reviewing the core samples and PID recordings, Carol Oz of PHS/FHD requested that three soil samples at 16, 21, and 26 feet bgs be submitted to the laboratory for PHC analysis. Groundwater was present in the open borehole after the boring had been advanced to about 20 feet bgs. A groundwater sample was collected after the boring had been advanced to the total depth of 28 feet bgs by inserting 1-inch diameter polyvinyl chloride (PVC) tubing, machine slotted with 0.001-inch diameter openings, from the bottom of the boring to the surface. Prior to collecting the groundwater sample, the depth-to-water was measured using an electric water- level sounder lowered into the PVC tubing. One quarter-inch diameter Teflon tubing, equipped with a check valve at the submerged end, was then inserted into the slotted PVC tube. Groundwater was brought to the surface within the Teflon tube by moving the Teflon tube up and down in a piston-like motion. Two additional borings, B5-2, and B5-3, were drilled along the southern and western margins of the former UST excavation, respectively (Figure 2). Both borings were drilled to 28 feet bgs°and soil samples were collected for laboratory submittal in both borings at 16, 21, and 26 feet bgs at' the request of Carol Oz. Samples were collected using a 2-foot long, 1-inch " diameter, Large-Bore Soil Sampler equipped with a clear plastic liner. No petroleum product I odor or discoloration were detected in core samples from these borings. Groundwater samples were collected in both borings at a depth of 22 feet bgs using the method described above. Borings B5=4 and B5-5 were drilled approximately 10 feet south and north of the former dispenser area, respectively, approximately 180 feet west-southwest of the former USTs (Figure 2). . Both borings were drilled to 21 feet bgs. Two-foot long soil-core samples were collected at 4, 9, 14, and 19 feet bgs in both.borings using the Large-Bore Soil Sampler. Dark-gray soil discoloration (interpreted in the field to be due to petroleum products) was 4 "117U VV_MWUSTM-PYr