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31 August 2005 <br />AGE -NC Project No. 02-0918 <br />Page 2 of 4 <br />• Total petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with EPA <br />Method 8015 Modified; and <br />• Benzene, toluene, ethylbenzene and total xylenes (BTEX) and the fuel additives methyl <br />tertiary -butyl ether (MTBE), di -isopropyl ether (DIPE), ethyl tertiary -butyl ether (ETBE), <br />tertiary -amyl methyl ether (TAME), tertiary butanol (TBA), ethylene dibromide (EDB) and <br />1,2-dichloroethane (1,2 -DCA) in accordance with EPA Method 8260B. <br />3.0. FINDINGS <br />Ground water elevation, flow direction, and gradient were determined from field data collected on <br />02 June 2005. The contaminant impact to ground water was quantified from the laboratory analytical <br />data. <br />3.1. GROUND WATER GRADIENT AND FLOW DIRECTION <br />At the time of the June 2005 sampling event, depths to ground water ranged from 41.93 (MW -1) feet <br />to 42.66 (MW -2) feet below the tops of the well casings (Table 1). The ground water elevations <br />calculated from the depth to water measurements averaged approximately 26.50 feet below mean <br />sea level (MSL) increasing approximately 2.40 feet since the February 2005 monitoring event The <br />net ground water flow was inferred to be towards the southeast at a calculated hydraulic gradient of <br />0.002 foot per foot (ft/ft). Figure 3 illustrates the contoured ground water elevations as measured on <br />02 June 2005. <br />During this monitoring event, the ground water level in the wells was approximately twelve feet <br />below the top of the well screens, indicating that the wells are properly screened and representative <br />of shallow ground water conditions. <br />3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES <br />TPH-g was detected in wells MW -1, MW -2 and MW -3 at concentrations of 220 micrograms per liter <br />(µg11), 21,000 µg/l and 29,000 µg/1, respectively. BTEX constituents were detected in ground water <br />samples collected from wells MW -2 and MW -3 at maximum concentrations of 5,000 µg11 benzene <br />(MW -3),2,200 µg/1 toluene (MW -3), 3,100 µg/l ethylbenzene (MW -2), and 7,300 µg/l total xylenes <br />(MW -3). <br />The fuel additive MTBE was detected in all three ground water samples collected from wells at <br />Advanced GeoEnviroamental, Inc. <br />