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' 09 October 2003 . AGE-NC Project No 99-0637 ' Page 2 of 4 ' Total petroleum hydrocarbons quantified as gasoline (TPH-g) and diesel (TPH-d) in accordance with EPA Method 8015-modified, • Benzene, toluene, ethylbenzene and total xylenes (BTEX) and in accordance with EPA ' Method 8021, and • Fuel additives Including methyl tertiary-butyl ether(MTBE),di-isopropyl ether(RIPE), ethyl ' tertiary-butyl ether (ETBE), tertiary-amyl methyl ether (TAME), tertiary butanol (TBA), ethylene dibromide (EDB) and 1,2-dichloroethane (1,2-DCA) in accordance with EPA Method 8260B ' 3.0. FINDINGS Ground water elevation, flow direction, and gradient were determined from field data collected ' onl2 August 2003 The MTBE-impact to groundwater was quantified from the laboratory analysis of the ground water samples lie 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION At the time of the August 2003 sampling event, depths to ground water ranged from 20 78 feet to 2198 feet below the tops of the well casings Ground water elevations at the site ranged from. 11 56 feet above mean sea level (MSL) in well MW9 to l2 54 feet above MSL in well MW2 (Table 1) Dunng this monitoring event, the ground water levels in the wells were at least ten to eleven feet below the tops of the well screens,indicating that the wells are screened properly to yield representative shallow ground water samples The ground water elevation at the site decreased approximately 3 49 feet between the May 2003 and August 2003 monitoring events I Ground water flow was inferred to be flowing toward the west to slightly northwest, away from the former UST area at an average gradient of 0 005 feet/feet Figure 3 illustrates the contoured ground water elevations as measured on 12 August 2003 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES ITPH-g, BTEX and the fuel oxygenates, excluding MTBE, were not detected in any of the ground water samples IMTBE was detected in the ground water samples collected from wells MW1, MW4, MW5, MW6 • and MW9 at concentrations ranging from 1 4 �ig/l in well MW6 to 1,100 µg/1 in well MW4 TBA Advanced GeoEnvironmental,Inc.