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' 30 April 2005 AGE-NC Project No 03-1070 Page 2 of 4, labeled, placed in a chilled container and transported under chain of custody to Cal Tech ' Environmental Laboratories (CTEL) of Paramount, a California Department of Health Services- certified analytical laboratory, for analysis The samples 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) In accordance with EPA Method 8260B, and ' • Fuel additives including methyl tertiary-butyl ether(MTBE),di-isopropyl ether(DIPS),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 14 February 2005 The contaminant impact to ground water was quantified from the laboratory analytical data 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION At the time of the February 2005 sampling event,depths to ground water ranged from 30 09(MW-2) feet to 31 59(MW-1)feet below the tops of the well casings (Table 1) The ground water elevations Icalculated from the depth to water measurements averaged approximately 19 63 feet below mean sea level (MSL) The net ground water flow was inferred to be towards the west to southwest at a calculated hydraulic gradient of 0 034 foot per foot(ft/ft) Figure 3 illustrates the contoured ground water elevations as measured on 14 February 2005 During this monitoring event, the ground water level in wells MW-2 and MW-4 were at least 0 39 feet below the top of the well screens, indicating that the wells are properly screened and representative of shallow ground water conditions Wells MW-1 and MW-3 were at least 3 48 feet above the tops of the well screen, however, the ground water samples, although collected from "flooded" wells, are representative of shallow ground water conditions because the aquifer is confined by overlying fine-grained materials and the wells are screened in the first encountered ground water unit ` IAdvanced GeoEnvironmental,Inc I