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I 03 October 2003 AGE-NC Project No 97-0290 ' Page 3 of 5 ' 24 SOIL-VAPOR SAMPLING AND ANALYSIS A set of soil-vapor samples were collected from the carbon-adsorption soil vapor extraction system ' on 11 March, 15 April, 23 June, 24 July,14 August and I 1 September 2003 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 cooler and transported under chain-of ' custody to MAI The samples were analyzed for • TPH-g in accordance with EPA Methods 8015CM and ' • BTEX and MTBE in accordance with EPA Method 8021B 3.0. FINDINGS ' Ground water elevation, flow direction and gradient were determined from field data collected on 28 August 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 six event in the two quarters, AGE determined the average TPH-g concentration, the average flow rate and calculated fthe approximate mass and volume of hydrocarbons removed 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION ' The depths to ground water ranged from 49 03 feet to 52 30 feet below the tops of the well casings Ground water elevations calculated from the well monitoring data ranged from 157 feet to 2 37 feet above mean sea level (MSL) The depth to ground water increased 3 7 feet since the previous quarter Ground water data is summarized on Table I The ground water flow direction at the former UST release area was south to southeast, with a I gradient of 0 003 ft/ft Ground water elevation contours based upon the data for the monitoring event are illustrated on Figure 3 32 ANALYTICAL RESULTS OF WATER SAMPLES TPH-g was detected in the water samples collected from wells MW-2 and MW-4 at concentration . of 10,000 µg/i micrograms per liter (µg/l) and 2,300 µg/1, respectively Benzene was detected in ground water samples MW-2 and MW-4 at concentrations of 2,100 µg/1 and 9 3 µg/1,respectively Advanced GeoEnvironmental,Inc.