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Site Background Information: Cherokee Truck Stop AGE-NC Project No. 97-0312 Page 9 of 11 geologic cross sections B-B', D-D', E-E' and G-G' were previously illustrated. Since initiation of ground water monitoring by AGE in March 2001, depth to ground water measurements have fluctuated between approximately 54 feet and 73 feet below the tops of the well casings. The inferred ground water flow direction beneath the site has generally been toward the northeast at gradients ranging between 0.0001 ft/ft and 0.007 ft/ft. Graphs illustrating depth to ground water and ground water elevation trends were included. MIGRATION OF PETROLEUM RELEASE Release(s) of petroleum hydrocarbons occurred from the former on-site USTs, including USTs Nos. 1 through 5,located along the northern edge of the site,UST No.6,located at the eastern edge of the site, and two waste oil USTs located in the southwest comer of the site (Figure 2). The majority of the UST release occurred from dispenser line leaks, based on sampling from the UST removal. During UST and product piping removal activities conducted in September 1997,it was noted that USTs Nos. 1 through 5 appeared to be in good condition;however, a hole was observed on the bottom of UST No. 6, beneath the fill port. Obvious field indications of hydrocarbon- impacted soil were observed immediately surrounding the USTs and product piping. TPH-g and TPH-d were detected at concentrations as high as 520 mg/kg and 32,000 mg/kg,respectively,in a sample collected approximately 2 feet below the east end of UST No.3 and at concentrations of 1,000 mg/kg and 11,000 mg/kg, respectively, in a sample collected at approximately 17 feet bsg, below the UST No. 6 excavation. TPH-g and TPH-d were detected in piping/dispenser samples at concentrations as high as 1,200 mg/kg and 16,000 mg/kg, respectively; BTEX constituents were detected at concentrations as high as 60 mg/kg(xylenes). Once released to the subsurface,the contaminants migrated through the fine-grained silty material below the UST areas,to a vertical depth of approximately 20 to 30 feet bsg at the northeastern UST location (UST Nos. 1 through 5), and as much as 70 to 75 feet bsg west of the former UST No. 6 location.Contamination in the area of former UST Nos. 1 through 5 does not appear to extend below 40 feet bsg;petroleum hydrocarbons were not detected in soil samples collected below 30 feet bsg from soil boring B 14. West of the former UST No. 6 area,vertical migration of TPH-g and BTEX contaminants appears to extend to depths as great as approximately 70 feet to 75 feet bsg. In a soil sample collected from boring MW-1 at 70 feet bsg, TPH-g and TPH-d were detected at concentrations of 5.3 mg/kg and 80 mg/kg, respectively; however, no petroleum hydrocarbon constituents were detected in a sample collected at 85 feet bsg from the same boring.Low detections of TPH-g and BTEX were reported in soil samples collected from boring MW-9 at depths of 90 feet and 100 feet bsg;however, no petroleum hydrocarbon contamination has been reported in ground water samples collected from the well to date. Advanced GeoEnvironmental,Inc.