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I l18 February 2003 AGE-NC Project No 96-0229 Page 5 of 9 3.0. FINDINGS Soil descnptigns were utilized to construct geologic cross sections of the site Field data was utilized to select soil samples for laboratory analysis and to determine ground water flow direction and gradient Hydrocarbon Impact to soil and ground water was assessed and quantified by laboratory analysis 31 STRATIGRAPHY Generally, a dark brown,damp medium dense,clayey sand was encountered at 5 feet bsg and a pale brown, damp,very stiff,silty clay with some fine sand was encountered at 10 feet bsg at both boring locations Between 15 and 20 feet bsg, finer-grained clayey sand underlain by clay was Identified in boring MW-11,whereas brown to red-brown silty sand was Identified in boring MW-12 Below 20 feet bsg In both borings,the soil consisted of a brown to gray,damp to saturated,medium dense,fine to coarse sand with some gravel at between 25 and 35 feet bsg, and gray-brown to red-brown, saturated, dense, clayey fine sand at between 40 and 45 feet bsg Boring logs are included In r • Appendix B General lithology beneath the site in cross-sectional view is depicted in Figures 5 and 6 ` Saturated soil was encountered at approximately 35 feet bsg in both borings, ground water levels were measured at approximately 32 feet bsg utilizing a Solinst water level meter 32 FIELD EVIDENCE OF HYDROCARBON-IMPACTED SOIL AND GROUND WATER I I No petroleum hydrocarbon odor,petroleum hydrocarbon vapor(using a PID)or discoloration were observed in soil sample duplicates collected from soil borings MW-11 and MW-12 3 3 GROUND WATER ELEVATION AND GRADIENT During the 25 November 2002 monitoring event, depths to ground water in wells MW-1 through MW-12 were measured at between 30 87 and 33 17 feet below the tops of the welt casings t I able 2) Ground water elevations were calculated to be between 20 30 feet(MW-5)and 22 18 feet(MW-12) below mean sea level (MSL), the ground water elevation decreased an average of 1 35 feet between the August 2002 and the November 2002 ground water monitoring events The ground water surface elevation at the site was within the screened Intervals of wells MW-2 through MW-I OA, MW-11 and M W-12 but was approximately 16 and 18 feet above the screen intervals in wells MW-1 and MW-IOB,respectively Advanced GeoE oviren mental,Inc