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r ' 05 May 2004 AGE-NC Project No, 95-0106 ' Page 2 of 4 The samples were transported in a' chilled. container under chain-of-custody'to -.Cal Tech Environmental Laboratories. (CTEL}, a California Department of Health Services (DHS)-certified analytical-laboratory, and analyzed for: ; Total 'petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with ' h6d 8015-Modified and EPA Met� Benzene,toluene,ethylbenzene and xylenes(BTEX); and the fuel additives methyl-tertiary- . • butyl ether(MTBE), tertiary butyl alcohol (TBA), di-isopropyl ether (DIPE), ethyl tertiary butyl ether(ETBE)',and tertiary amyl methyl ether(TAME), 1,2-dibromoethane(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. The hydrocarbon impact to ground water was quantified by laboratory analysis of the ground water samples. 3.1GROUNDWATER ELEVATION AND FLOW DIRECTION ' The relative ground water elevation ranged from 32.69 feet (MW-6 upper) to 33.51 feet (MW-2), increasing an average of 0.75 ,feet since the. September 2003 monitoring event. The water table " appears as a northerly plunging ridge; the east limb of the ridge flows toward the northeast at a ' gradient of approximately 0.006 feet/feet.and the west limb flows toward the northwest at a gradient of approximately'0.007 feet/feet. Ground water elevation data is presented in Table 1 'while the contoured ground water elevation data is shown on Figure 3. •3.2. ANALYTICAL RESULTS OF GROUNDWATER SAMPLES- ; ,TPH-g was 'detected at concentrations of 1,200 micrograms per liter (µg/L) and 1,7000 µg/L in. samples from wells MW-1 and MW-4; respectively (Figure 4). F BTEX compounds were detected in wells MW-1 and MW=4 at the following concentrations: benzene 40 µg/L iri well MW-4;toluene 170`µtWL and 2.8 µg/L,ethylbenzene 24 µg/L,and 55 µg/L ' and xylenes 209 µg/L•and-20.9, µg/L, respectively. Benzene was not detected this quarter in.the samples collected'from well Mw-j... . Advanced GeoEnvironmental,Inc.