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r` 07 April 2003 AGE-NC Project No. 97-0360 I Page 2 of 4 i collection, the samples were properly labeled, placed in a chilled container and transported under chain-of custody to Cal Tech Environmental Laboratories (CTEL), a California Department of Health Services-certified laboratory. The samples were analyzed for: 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(BTE&X) and methyl tertiary-butyl ether (MTBE) in accordance with EPA Method 8021; and • Fuel additives including 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 on 19 November 2002. The hydrocarbons-impact to ground water was quantified from the laboratory analysis of the ground water samples. 3.1. GROUNDWATER GRADIENT AND FLOW DIRECTION 4,5 l�r�lq'S At the time of the November 2002 sampling vent,depths to ground water in wells MW 1 through MWS and EWl ranged from 7.40 feet to 8.7 feet-below the well heads. Ground water elevations at the site ranged from 3.55 feet above mean sea level(MSL)in well MW4 to 3.74 feet above MSL in well MW5 (Table 1). The ground water flow direction was inferred using ground water elevation data from the monitoring wells on-site. Well MW2 was not used in ground water flow direction or gradient determination because it is screened at a deeper interval than the other wells. The flow direction was inferred to be toward the north at a gradient of 0.002 feet/feet. Figure 3 illustrates the contoured ground water elevations as measured on 19 November 2002. 3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was only detected in the ground water sample collected from well EW1 at a concentration of 160 micrograms per liter (�Lg/l) TPH-d was also only detected in the sample from EW 1 at a Advanced GevEnvironmental,Inc.