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07 July 2003 AGE-NC Project No. 95-0167 Page 2 of 4 was transferred into 40-m1 volatile organic analysis(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), a California Department of Health Services (DHS)-certified laboratory, and were analyzed for: • Total petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with EPA Method 8015 Modified; • Benzene, toluene, ethylbenzene and total xylenes (BTEX) and the fuel additives methyl- tertiary butyl ether (MTBE), di-isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), tertiary-amyl methyl ether(TAME),tertiary butyl alcohol(TBA), 1,2-dibromoethane(EDB) and 1,2-dichloroethane (1,2-DCA) in accordance with EPA Method 8260B. 3.0. 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 March 2003 sampling event, depths to ground water ranged from 14.72 feet to 1552 feet below the tops of the well casings. Ground water elevations at the site ranged from 5.11 feet(MW-5) to 6.36 feet (MW-2) below mean sea level (MSL). Ground water was within the screened interval of MW-1 through MW-6, and had and average elevation increase of 0.76 feet since the last monitoring event. 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 March 2003 monitoring event was in the form of a west-northwest-plunging trough; net flow of ground water at the site was determined to be to the west-northwest under an average gradient of 0.008 ft/ft.Figure 3 illustrates the contoured ground water elevations as measured on 06 March 2003. 3.2. LABORATORY RESULTS OF GROUND WATER SAMPLES TPH-g was detected in the water samples collected from monitoring wells MW--I and MW-2 at concentrations of 1,400 micrograms per liter (�Lg/l) and 340 gg/I, respectively. Advanced Geo Environmental,Inc.