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' 29 October 2002 AGE-NC Project No 95-0167 Page 2 of 4 transferred into 40-m1 VOA vials containing 0 5 ml 18%hydrochloric acid as a sample preservative After collection, the samples were properly labeled, placed in a chilled container and transported under chain-of-custody to Cal Tech Environmental Laboratories (CTEL), and were analyzed for ' - Total petroleum hydrocarbons quantified as gasoline (TPH-g) In accordance with EPA Method 8015 Modified, and ' - Benzene,toluene,ethylbenzene and total xylenes(BTEX)and the fuel additives di-isopropyl ether(DIPE),ethyl tertiary-butyl ether(ETBE),methyl tertiary-butyl ether(MTBE),tertiary- ' amyl methyl ether(TAME), tertiary butanol (TBA),methanol, ethanol, 1,2-dibromoethane (EDB) and 1,2-dichloroethane (1,2-DCA) in accordance with EPA Method 8260B ' 30 FINDINGS Ground water flow direction, elevation, and gradient were determined from data collected in the field The hydrocarbon impact to ground water was quantified by the laboratory data obtained from the ground water samples ' 3 1 GROUND WATER ELEVATION AND GRADIENT For the August 2002 sampling event, depths to ground water ranged from 14 42 feet to 15 49 feet ' below the tops of the well casings Ground water elevations at the site ranged from 4 81 feet(MW-5) to 6 40 feet (MW-2) below mean sea level (MSL) Ground water was within the screened interval of MW-1 through MW-6 The ground water flow direction was determined by plotting and contouring the ground water elevation data The shape of the water table at the time of the August 2002 monitoring event was in ' the form of a northwest-plunging trough, net flow of ground water at the site was determined to be to the northwest under an average gradient of 0 03 ft/ft Figure 3 illustrates the contoured ground water elevations as measured on 23 August 2002 32 LABORATORY RESULTS OF GROUND WATER SAMPLES ' TPH- was detected in the water samples collected from monitoring wells MW-1 and MW-2 at 2 g P concentrations of 23,000 micrograms per liter(µg11) and 250 µg/l, respectively • ' Advanced GeoEnvironmental,Inc