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' 10 February 2004 AGE-NC Project No 01-0839 ' Page 2 of 3 ' a California Department ofHealth Services-certified analytical laboratory,for analysis The samples were analyzed for • Total petroleum hydrocarbons as gasoline(TPH-g)in accordance with EPA Method 8015M, ' and • Benzene, toluene, ethylbenzene and total xylenes (BTEX), di-isopropyl ether(RIPE), ethyl ' tertiary-butyl ether(ETBE),methyl tertiary-butyl ether(MTBE),tertiary-amyl methyl ether (TAME), tertiary-butyl alcohol (TBA),ethylene dibromide (EDB) and 1,2 dichloroethane (1,2-DCA) by EPA Method 8260B I 3.0. FINDINGS The ground water elevation, flow direction, and gradient were determined from field data The contaminant impact to ground water was quantified by the laboratory analytical data • 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION I At the time of the December 2003 sampling event, depths to ground water ranged from 69 75 feet I to 70 05 feet below the tops of the well casings(Table 1), ground water elevations at the site ranged from 36 12 feet(MW-2)to 36 22 feet(MW-1)below mean sea level(MSL) During this monitoring event,the ground water level was within the screened interval of the wells, indicating that the wells Iwere properly screened to yield representative shallow ground water samples The ground water flow direction was calculated from the well elevation data The net ground water rflow direction was inferred to be towards the north at a gradient of between 0 001 ft/ft and 0 002 ft/f1 (Figure 3) I 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected only In the water sample collected from well MW 1, at a concentration of 900 micrograms per liter(µg/1) IThe fuel additives MTBE and 1,2-DCA were detected in water samples MW1 and MW2 at maximum concentrations of 890 µg/1 and 5 3 pg/l, respectively INo other analytes were detected at or above laboratory detection limits in the ground water samples analyzed The laboratory analytical results are summarized on Table 2 The laboratory report(CTEL Advanced GeoEnvironmental,Inc I