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' 21 December 2005 . AGE-NC Project No 95-0128 ' Page 2 of 4 ' hydrochloric acid(sample preservative)and 1-liter amber bottles without preservative The samples collected were logged on a chain of custody form, placed in a chilled container and transported to Cal Tech Environmental Laboratories (CTEL) a California Department of Health Services (DHS)- certified laboratory, for analysis The ground water samples were analyzed for • Total petroleum hydrocarbons quantified as gasoline and diesel (TPH-g and TPH-d) In ' accordance with EPA Method 8015 Modified, • Benzene, toluene, ethylbenzene and xylene (BTEX) in accordance with EPA 8260B, and ' • Fuel additives dl-isopropyl ether (DIPS), ethyl tertiary-butyl ether(ETBE), methyl tertiary- butyl ether(MTBE),tertiary-amyl methyl ether(TAME),tertiary butanol(TBA),methanol, ethanol, 1,2-dibromoethane (EDB) and 1,2-dichloroethane (1,2-DCA) in accordance with ' EPA Method 8260B 3.0. FINDINGS Ground water elevations were determined by subtracting the measured depths to ground water from the surveyed casing elevations Ground water flow directions were determined by contouring the water elevations on a scaled site plan Contaminant impact to ground water was assessed by laboratory analysis 3 1 GROUND WATER ELEVATION AND GRADIENT The depth to ground water on 11 August 2005 ranged from 33 21 feet (MW-18) to 36 30 feet (MW-13)below the tops of the well casings The ground water elevation calculated from the same data,ranged from 21 21 feet(MW-7)to 23 41 feet(MW-17)below mean sea level(MSL) The depth to ground water averaged 36 14 feet this quarter,a decrease of approximately 2 4 feet since the last sampling event The ground water table occurred within the screened interval of the shallow- screened monitoring wells, however, wells MW-I to MW-3, MW-I IB, MW-12B and MW-18 are deeper-screened wells and are currently drowned The depth to ground water and ground water elevation data is summarized In Table 1 The ground water flow direction continues to he toward the north through east, with an apparent depression in the water table (MW-5 and MW-6) at the I northeast corner of the site Ground water gradients range between 0 01 ft/ft and 0 02 ft/ft across and north of the site and the lowest gradient was at 0 006 ft/ft east of the site under Pacific and Rialto avenues The ground water flow directions and gradients are depicted on Figure 3 IAdvanced GcoEnvironmental,Inc