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O8 November 2002 AGE-NC Project No.02-0918 Page 6 of 9 4.0. FINDINGS The stratigraphy and ground water hydrogeology underlying the site was characterized from the field descriptions. Contaminant impact to ground water samples was assessed by laboratory analysis. 4.1. STRATIGRAPHY AND DEPTH TO GROUND WATER Silt,sand and clay with a tan,brown or gray color,apparently depending on hydrocarbon impact,was generally encountered from a depth of approximately 5 feet to 65 feet bsg.Silt was the dominant soil type encountered to total depth in the boreholes.Silty sand was encountered between 10 and 15 feet bsg(possible backfill)in borings B1,B2 and B3 and between 20 and 26 feet bsg and 45 and 50 feet bsg in boring B1. A thin clay horizon (less than 5-foot thick) was encountered at approximately 25 feet bsg in borings B2 through 134; clay was also identified at approximately 15 feet bsg and. between 40 and 45 feet bsg in boring B 1.A stratigraphic cross section is depicted in Figure 3; soil boring logs are provided in Appendix A. Ground water was encountered at a depth of 50 feet bsg during drilling;the ground water elevation data are provided in Table 3. 4.2. HYDROCARBON-IMPACTED SOIL A total of nineteen soil samples were analyzed for hydrocarbons and fuel additives. • TPH-g was detected in six soil samples from boring B1, two soil samples from boring B3 and two samples from boring B4.The highest concentration of TPH-g(6,100 milligram per kilogram-mg/kg)was detected in the soil sample collected from boring B1 at 20 feet bsg (B1-20); low concentrations of TPH-g, at or below 20 mg/kg, were detected in the other impacted soil samples. • Various BTEX compounds were detected in fourteen of the soil samples analyzed. The highest concentration of a BTEX compound was detected in soil sample B1-20 (xylene 350 mg/kg).BTEX compounds were detected in the remaining soil samples at concentrations at or below 89 mg/kg. • BTEX compounds were detected in soil samples collected from boring B1 to the total depth of the soil boring; BTEX compounds were detected in the soil samples collected from the remaining borings at varying depths. • The highest benzene concentration was detected in soil sample B 1-40 at 6.2 mg/kg. Advanced GeoEnvlroamental,Inc.