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`%OW 1"W Site Background Information: Cherokee Truck Stop AGE-NC Project No. 97-0312 Page 4 of 11 Stockpile sampling was summarized the AGE's Quarterly Report-December 1997, dated 13 February 1998. • June 1999-Soil borings B 14 through B 17 and monitoring well UST-6 were installed at the site and soil and grab water samples were collected. The borings were advanced to further define the hydrocarbon-impacted soil plume;UST-6 was installed to delineate the northern extent of hydrocarbon-impacted ground water.Borings B 14 through B 17 were advanced to a vertical depth of approximately 100 feet below surface grade (bsg); boring UST-6 was drilled to a vertical depth of 75 feet bsg.TPH-g was detected in samples B 14-20 and B 15-15 at concentrations of 570 mg/kg and 540 mg/kg,respectively.TPH-d was detected in six of the 24 samples analyzed (B14-20, B14-30, B15-15, B15-20, B17-25 and B17-40) at concentrations as high as 13,000 mg/kg(B 14-20).Benzene was detected in sample B 14-20 at a concentration of 4.1 mg/kg.Toluene,ethylbenzene and xylenes were detected in samples B 14-20 and B 15-15 at concentrations as high as 9.8 mg/kg. Other petroleum hydrocarbons were not detected in the 24 soil samples analyzed.MTBE was detected by EPA Method 8260 in samples B 14-20, B 17-25 and B 17-40 at concentrations of 0.41 mg/kg, 12 mg/kg and 8.1 mg/kg,respectively. Tert-butanol was detected in sample B14-20 at a concentration of 0.3 mg/kg. Other oxygenates were not detected in these three samples or in sample B15-15. MTBE was detected by EPA Method 8020 in samples B14-30 and B 17-50 at concentrations of 0.051 mg/kg and 0.54 mg/kg,respectively.Additionally,grab ground water samples were collected from borings B-14, B-15 and B-17. TPH-g, TPH-d, MTBE and BTEX were detected in each sample.MTBE concentrations ranged from 6.4µg/1 in the sample from B-14 to 9,700 µg/1 in the sample from B-17. • September 1999-Twelve soil borings were advanced at the site to further define the lateral and vertical extent of hydrocarbon-impacted soil.Borings B 18 through B29 were advanced to vertical depths between 30 and 70 feet bsg. TPH-g was detected in only one sample (B21-10) at a concentration of 6.7 mg/kg. TPH-d was detected in 11 of the 39 samples analyzed at concentrations as high as 660 mg/kg(B21-10).Benzene was detected in four of the 39 samples at concentrations as high as 0.057 mg/kg. Toluene was detected in sample B2140 at a concentration of 0.091 mg/kg. Ethylbenzene and xylenes were not detected in the soil samples analyzed from the September 1999 drilling.MTBE was detected in three of seven soil samples analyzed by EPA Method 8260 at concentrations as high as 2.7 mg/kg. Other oxygenates were not detected. • 30 July 2002-Ground water monitoring well UST-1 was destroyed by over-drilling to total depth. Following over-drilling, the boring was backfilled to surface grade with portland cement in accordance with EHD regulations. • 06 December 2002-One ground water monitoring well(UST-7)was installed to a depth of 90 feet bsg; the well screen of UST-7 was recorded as placed between 85 feet and 90 feet bsg. Soil samples were collected at 25 feet bsg and 45 feet bsg. The physical properties of Advanced GeoEnvironmental,Inc.