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i 4 Report 402.331-87.4 Drilling and Sampling Procedures. Borehole logging and sampling was conducted by a DER Civil Unit geologist. The borings were drilled by Tom McMullen of Exceltech utilizing aMobile B-53 drill rig and 6 inch continuous flight solid stem: augers. No fluids were added to the borings while. drilling. Soil samples collected from the borings were drive samples taken with a 2.5" I.D. split spoon sampler with three 2.5" X 6" brass tube liners. The sampler was driven 18 inches into the undisturbed soil beyond the tip of the auger by a 140 lb - [ safety hammer with a 30" drop. The sampling interval ranged- from 1.5 to 5 f feet apart. The soil samples were logged and visually classified (ASTM D-2487-83) by the on-site geologist. Prior to each soil sampling effort, the split spoon sampler and brass tube liners were thoroughly washed (with potable water and TriSodium Phosphate) to avoid cross contamination. The drive samples selected for laboratory analysis were retained in the brass liners, labeled, capped with polyethylene lids, sealed with electrical tape and placed on ice. l A single water sample from each borehole was obtained by lowering a �! teflon bailer into the upper one .foot of the water column in each completed borehole and retrieving a sample. The water samples were then decanted into 40 ml VOA (Volatile Organic Analysis) vials, labeled, and placed on ice. All of the soil and water samples were transported to DER's chemical laboratory. Soil and water samples selected for chemical analysis were submitted to Clayton Environmental Consultants, Inc. Field Work Field work for this study consisted of drilling:-and sampling two borings (see Figure 2) in the vicinity of the underground fuel storage tank. Prior to drilling, underground utilities were located and marked by Service _Center personnel. The top and bottom of the tank was measured-to be at 3 and 8 feet below ground surface, .re.spectively. . Two exploratory borings (B1 and B2) were drilled and sampled to depths of 13.5 and 15.5 feet respectively: Ground water was encountered .at approximately 8'08" in boring -Bl and 9102" in boring B2. The upper .4 to 6.5 feet of material encountered in each boring is a moist, stiff, 'low plasticity, greenish-gray silty clay. The appearance and stiffness of this material suggests that the clay represents native soil. Below this silty clay layer (to termination depth), both borings penetrated a moist, stiff, brown clayey silt or clayey silt with sand. Moderate to strong product odor was noted in all soil samples recovered above the water table in boring Bl. No product odor was detected from any of the soil samples obtained from boring B2. Free product was found floating on the ground.water in both boreholes. Apparent product thickness was measured and found to be 3.5 .inches in borehole Bl and 0.5 inches in borehole B2. 'Drilling and sampling was completed on November 14, 1986 and the boreholes grouted to the surface. Borehole logs with the sampling intervals are included in Appendix A.