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20 February 2003 AGE-NC Project No 97-0290 Page 3 of 6 24 SOIL-VAPOR SAMPLING AND ANALYSIS A set of soil-vapor samples were collected from the carbon-adsorption soil vapor extraction system on 28 October 2002 The soil-vapor samples were collected in Tedlar vapor bags using a vacuum pump attached to the influent and effluent stream The samples were labeled, placed in a pre-chilled I cooler and transported under chain-of-custody to McCampbell Analytical Laboratories Inc The samples were analyzed for 0 TPH-g iIx accordance with EPA Methods 8015 Modified and 0 BTEX and MTBE in accordance with EPA Method 8020 I 3.0. FINDINGS Ground water elevation, flow direction and gradient were determined from field data collected on 13 January 2003, the contaminant impact to ground water was quantified from the ground water laboratory data From field and laboratory data collected at the SVE remediation system on 28 October 2002, AGE determined the average TPH-g concepti ation, the average flow rate and calculated the approximate mass and volume of hydrocarbons removed 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION The depths to ground water ranged from 46 25 feet to 51 31 feet below the tops of the well casings Ground water elevations calculated from the well monitoring data ranged from 0 58 feet to 1 0 feet above mean sea level(MSL) The depth to groundwater increased 0 8 feet since the previous quarter Ground water data is summarized on Table 1 The ground water flow direction at the former UST release area was south to southwest, with a gradient of 0 002 ft/ft Ground water elevation contours based upon the data for the monitonng event are illustrated on Figure 3 3 2 ANALYTICAL RESULTS OF WATER SAMPLES TPH-g was detected in water samples collected from wells MW-2, MW-4, at concentrations ranging between 120 gg/1 micrograms per liter (µg/l)in ground water samples MW-6 and MW-7)to 960 µg/1 in sample MW-2 Advanced GeaRnvtronznental,Inc I