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r11 September 2002 . AGE-NC Project No 96-0249 Page 3 of 6 3.0. FINDINGS Ground water elevation, flow direction and gradient were determined from field data collected on 13 June 2002,the contaminant impact to ground water was assessed from laboratory analysis of the ground water samples collected on 13 June 2002 3 1 GROUND WATER ELEVATION AND GRADIENT The depths to ground water in wells MW-1 through MW-6 vaned from 10 68 to 12 74 feet below the tops of the well casings, ground water elevations were calculated to be between 2 90 feet and 3 91 feet below mean sea level Ground water elevation at the site increased an average 0 71 feet ' between the March 2002 and the June 2002 ground water monitoring events The ground water elevation data for MWA through MW-6 during the June 2002 ground water monitoring event is depicted in Figure 3 Based on the ground water elevation data, ground water was inferred to be flowing toward an east- west-trending depression of the water table extending from the east side of Flag City Chevron lie through the domestic well at the Three B's Truck Plaza (Figure 3) Ground water gradients range from approximately 0 001 ft/ft around Flag City Chevron to 0 01 ft/ft around Three B's Truck Plaza 3 2 LABORATORY RESULTS OF MONITORING WELL GROUND WATER SAMPLES ' A total of six ground water samples were submitted for analysis to McCampbell Analytical Inc (MAI), a DHS-certified laboratory ' TPH-g was detected in the water samples collected from wells MW-1, MW-2, MW-3, MW-5 and MW-6 at concentrations ranging between 250 and 17,000 micrograms per liter(µg/1),the laboratory ' reported each TPH-g chromatogram as having unmodified or weakly modified gasoline patterns TPH-d was detected in water samples collected from MWA, MW-2, MW-3 and MW-6 at concentrations ranging between 370 and 1,500 µg/1, however, the laboratory noted that the diesel ' range hydrocarbons in the samples had non-diesel patterns and the samples contained significant lighter gasoline range compounds ' BTEX compounds were detected in water samples collected from MW-1,MW-2,MW-3,MW-5 and MW-6 at concentrations ranging as high as 5,500 µg/1 (benzene, MW-6) ' MTBE was detected by EPA Method 8260 Modified in water samples MWA, MW-2, MW-4 and • MW-6 at concentrations as high as 90 µg/1(MW-4) In addition, the oxygenated fuel additive TBA Advanced GcoEnvironmental,Inc