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' 25 August 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 r • TotaI 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 826013, and ' • Fuel additives including methyl tertiary-butyl ether(MTBE),dl-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 17 May 2005 The contaminant impact to groundwater was quantified from the laboratory analytical data 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION ' At the time of the May 2005 sampling event,depths to ground water ranged from 27 43 (MW-2)feet to 27 83 (MW-1) feet below the tops of the well casings (Table 1) The ground water elevations ' calculated from the depth to water measurements averaged approximately 16 57 feet below mean sea level (MSL) The net ground water flow was inferred to be towards the east at a calculated ' hydraulic gradient of 0 003 foot per foot (ft/ft) Figure 3 illustrates the contoured ground water elevations as measured on 17 May 2005, ' During this monitoring event, the ground water level in well MW-2 was 2 57 feet below the top of the well screen, indicating that the well is properly screened and representative of shallow ground water conditions Wells MW-1, MW-3 and MW-4 were at 7 17 feet, 7 35 feet and 2 41 feet, respectively, above the tops of the well screens, 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 ' Advanced GeoEnvironmtntal,Inc I