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28 August 2003 AGE -NC Project No. 03-1063 Page 2 of 7 P-15 was advanced adjacent to an abandoned in -ground hydraulic lift located in the wash -down and detailing unit of the auto body shop building. Soil probe borings P-16 and P-17 were completed at the former locations of the waste oil UST and gasoline UST, respectively. Soil probe borings P-1 through B-12, and P-15 were advanced to depths of 15.5 feet below surface grade (bsg) to assess the potential for hydrocarbon impacts to soil and/or ground water below the base of each of the lift units. Probe borings P-13 and P-14 were advanced to a depth of 10.5 feet bsg to assess the vertical extent of potential hydrocarbon impacts at locations of surficial staining. Soil probe borings P-16 and P-17 were advanced to depths of 30.5 feet bsg to assess the vertical extent of potential petroleum hydrocarbon impacts to soil and/or ground water related to the former gasoline and waste oil USTs. Discrete soil samples were collected from each of the soil probe borings at selected depths below the vertical extent of former UST, hydraulic lift, and surficial staining locations. Ground water samples were collected from soil probe borings P-6, P-12, and P-17. Ground water table was encountered at approximately 13 feet bsg. Ground water samples were collected from the top of the ground water table in probe borings P-6 and P-12 at a sampling interval of 13 to 18 feet bsg. A ground water sample was collected from boring P-12 at a sampling interval of 11 to 16 feet bsg. The only reported detections of total petroleum hydrocarbons (TPH) were in the soil sample collected from soil probe boring P-6. TPH as gasoline (TPH-g), TPH as diesel (TPH-d) and TPH as motor oil (TPH-mo) were reported in the soil sample collected at 10.5 feet bsg from probe boring P-6' at concentrations of 1.4 milligrams per kilogram (mg/kg), 13,000 mg/kg, and 16,000 mg/kg, respectively. However, the analytical laboratory reported that the chromatogram for the detection of gasoline -range (C6 -C 12) and diesel -range (C 10 - C23) hydrocarbons did not match the gasoline and diesel standards, respectively, and was assumed to be hydraulic fluid. TPH-d and TPH-mo were reported in ground water sample P-6 at concentrations of 2,300 micrograms per liter (µg/1) and 3,300 µg/1, respectively. 2.3. MONITORING WELL INSTALLATION Three monitoring wells were installed at the site in 2002 by Kleinfelder, Inc. Each well was installed to a depth of approximately 30 feet bsg. Based upon data collected from the wells, ground water flow direction was shown to flow northwest; the depth to ground water was approximately 21 feet bsg. The detection of petroleum hydrocarbons in any of the wells could not be confirmed. Advanced GeoEnvironmental, Inc.