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.-: 29 July 2.002 AGE-NC Project No. 97-0360 Page 2of3 sample preservative and into one 1-liter amber bottle without 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), 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 i accordance with EPA Method 8015 Modified; • Benzene, toluene, ethylbenzene and total xylenes (BTEX) and methyl tertiary-butyl ether (MTBE) in accordance with EPA Method 8 02 1; and i ' Fuel additives including MTBE,di-isopropyl ether IPE ethyl tertiary-butyl ether ETBE , - g (DIPE), Y ( ) 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 I ! Groundwater elevation, flow direction, and gradient were determined from field data collected on 13 May 2002;the contaminant impact groundwater was quantified by the laboratory analytical data. I ' 3.1. GROUND WATER GRADIENT AND FLOW DIRECTION I At the time of the May 2002 sampling event,depths to ground water in wells MW 1 through MW5 and EWl ranged from 7.89 feet to 9.42 feet below the well heads. Ground water elevations at the site ranged from 2.98 feet above mean sea level (MSL) in well MW2 to 3.22 feet above MSL in well MW4 (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 east-southeast at a gradient of 0.0006 feetifeet.Figure 3 illustrates the contoured ground water elevations as measured on 13 May 2002. 3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the ground water samples collected from wells MWl and EW1 at concentrations of 110 micrograms per liter(µg/1)and 100µg/l,respectively.No other analytes were detected at or above laboratory reporting limits in the ground water samples. Advanced GeoEnvironmental,Inc.