Laserfiche WebLink
4 Report 402.331-87.4 <br /> Drilling and Sampling Procedures <br /> Borehole logging and sampling was conducted by a DER Civil Unit <br /> geologist. The borings were drilled by Tom McMullen of Exceltech utilizing <br /> a Mobile B-53 drill rig and 6 inch continuous flight solid stem augers. No <br /> fluids were added to the borings while drilling. Soil samples collected <br /> from the borings were drive samples taken with a 2.5" I.D. split spoon <br /> sampler with three 2.5" X 6" brass tube liners. The sampler was driven 18 <br /> inches into the undisturbed soil beyond the tip of the auger by a 140 lb <br /> safety hammer with a 30" drop. The sampling interval ranged from 1.5 to 5 <br /> feet apart. The soil samples were logged and visually classified (ASTM <br /> D-2487-83) by the on-site geologist. <br /> Prior to each soil sampling effort, the split spoon sampler and brass <br /> tube liners were thoroughly washed (with potable water and TriSodium <br /> Phosphate) to avoid cross contamination. The drive samples selected for <br /> laboratory analysis were retained in the brass liners, labeled, capped with <br /> polyethylene lids, sealed with electrical tape and placed on ice. <br /> A single water sample from each borehole was obtained by lowering a <br /> teflon bailer into the upper one foot of the water column in each completed <br /> borehole and retrieving a sample. The water samples were then decanted into <br /> 40 ml VOA (Volatile Organic Analysis) vials, labeled, and placed on ice. <br /> . All of the soil and water samples were transported to DER's chemical <br /> laboratory. Soil and water samples selected for chemical analysis were <br /> submitted to Clayton Environmental Consultants, Inc. <br /> Field Work <br /> Field work for this study consisted of drilling and sampling two <br /> borings (see Figure 2) in the vicinity of the underground fuel storage tank. <br /> Prior to drilling, underground utilities were located and marked by Service <br /> Center personnel. The top and bottom of the tank was measured to be at 3 <br /> and 8 feet below ground surface, respectively. <br /> Two exploratory borings (B1 and B2) were drilled and sampled to depths <br /> of 13.5 and 15.5 feet respectively. Ground water was encountered at <br /> approximately 8'08" in boring B1 and 9'02" in boring B2. The upper 4 to 6.5 <br /> feet of material encountered in each boring is a moist, stiff, low <br /> plasticity, greenish-gray silty clay. The appearance and stiffness of this <br /> material suggests that the clay represents native soil. Below this silty <br /> clay layer (to termination depth), both borings penetrated a moist, stiff, <br /> brown clayey silt or clayey silt with sand. Moderate to strong product odor <br /> was noted in all soil samples recovered above the water table in boring B1. <br /> No product odor was detected from any of the soil samples obtained from <br /> boring B2. Free product was found floating on the ground water in both <br /> boreholes. Apparent product thickness was measured and found to be 3.5 <br /> inches in borehole B1 and 0.5 inches in borehole B2. <br /> • Drilling and sampling was completed on November 14, 1986 and the <br /> boreholes grouted to the surface. Borehole logs with the sampling intervals <br /> are included in Appendix A. <br />