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10 August 2005 AGE-NC Project No 02-0964 Page 2 of 4 ' monitoring well designation, date,time of sampling, and the sampler's initials and transported in a chilled container under chain of custody to Cal Tech Environmental Laboratories (CTEL), a Department of Health Services (DHS)-certified analytical laboratory for analysis The sample was ' analyzed for • Total petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with EPA Method 8015M, • Volatile aromatic compounds benzene,toluene,ethylbenzene,and total xylenes(BTEX) with ' fuel oxygenates tertiary butanol(TBA),di-isopropyl ether(DIPE), ethyl tertiary-butyl ether (ETBE), tertiary-amyl methyl ether(TAME), methyl tertiary butyl ether(MTBE), and fuel lead scavengers ethylene dibromide(EDB)and 1,2-dichloroethane(1,2-DCA)in accordance ' with EPA Method 8260B ' 3.0. FINDINGS Ground water elevation and flow direction were inferred from field data, hydrocarbon-impact to ground water was quantified by laboratory analysis of the ground water sample ' 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION The elevation of ground water in each of the monitoring wells was calculated by subtracting the depth to ground water from the surveyed relative casing elevations(Table 1) Depths to ground water ranged from 28 07 feet below top of casing(btoc)to 28 49 feet btoc Ground water elevations at the site ranged from 16 38 feet(MW-3)to 17 30 feet(MW-1)below mean sea level(MSL) The ground water gradient was calculated to be approximately 0 008 foot/foot (ft/ft)toward the east-northeast During this monitoring event,the ground water elevations were within the screened intervals of the ' wells Figure 3 illustrates the contoured ground water elevations as measured on 16 June 2005 3 2 ANALYTICAL RESULTS OF GROUND WATER SAMPLES During this monitoring event,a sample was only taken from well MW-1 TPH-g was detected in the ' water sample from well MW-1 at a concentration of 11,000 micrograms per liter(µg/1),benzene was detected at a concentration of 190 µg/l, toluene was detected at a concentration of 25 µg/l, and ethylbenzene and total xylenes were detected at concentrations of 2,000 µg11 and 5,250 µg/l, ' respectively (Table 2) 1,2-DCA was detected was non-detect this quarter(Table 3) No additional target analytes were detected at or above laboratory reporting limits in the ground water sample from Advanced GeoEnvironmental,Inc 1