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1 j , <br /> 24 August 1998 <br /> AGE-NC Project No 96-0232 <br />' Page 5 of 8 <br />' 3 1 SOIL PROFILE <br /> r A pale brown to red-brown, silty, poorly graded fine sand was encountered from surface grade to <br />' depths of approximately 20 feet in each boring A pale brown to dark brown,fine sandy,clayey,very <br /> stiff silt was generally encountered from 20 feet to 30 feet bsg A mottled red-brown and brown, <br /> silty,poorly graded fine sand was encountered from 30 feet to 40 feet bsg A brown and gray,poorly <br /> sorted, fine to coarse sand,was generally encountered at depths between 40 feet and 50 feet bsg A <br /> dark brown, very stiff, clayey silt was encountered at depths greater than 50 feet bsg <br /> Saturated soil was encountered in each boring at depths between 15 feet and 20 feet bsg Boring logs <br /> are included in Appendix A General lithology beneath the site in cross sectional view is depicted 4 <br /> in Figures 3 and 4 <br /> 3 2 FIELD EVIDENCE OF HYDROCARBON-IMPACTED SOIL AND GROUND WATER <br /> Neither petroleum hydrocarbon odor nor discoloration were observed in soil or ground water <br /> samples collected from MW-5 through MW-7 Organic vapor was detected from a soil sample <br /> duplicate collected from MW-7 at a concentration of 0 1 parts per million (ppm) Organic vapors <br /> were not detected in other soil samples <br /> - <br /> 3 3 GROUND WATER ELEVATION AND GRADIENT <br /> I r <br /> The depths to ground water in monitoring wells MW-1 through MW-7 were measured between 6 50 <br /> to 10 22 feet below the tops of the well casings Between February 1998 and July 1998, ground . <br />' water elevation generally decreased an average,6 88 feet at the site The ground watefelevation data <br /> for MW-l'though MW-7 during July's ground water monitoring event is depicted in Figure 8 <br /> 1 In July 1998,the gradient was calculated to be 0 003 ft/ft, or approximately 14 feet per mile (Figure <br /> 3)for the area located between wells MW-1 through MW-7 Ground water monitoring data collected <br />' in the area of MW-1 through MW-7 suggests that the ground water flow direction was generally <br /> west northwest Due to the low gradient at the site, slight variations in ground water measurements <br /> or changes of recharge/discharge of the local ground water could greatly modify ground water flow <br /> direction , <br />' 34 RESULTS OF SOIL SAMPLE ANALYSIS _ <br /> A total of four soil samples were submitted for analysis of TPH-g, TPH-d, BTEX and fuel <br /> r <br /> ` Advanced GeoEnvironmental,Inc <br /> s <br /> r <br />