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I03 December 2003 <br /> AGE-NC Project No 95-0184 <br />' Page 2 of 5 <br />' 2 2 COLLECTION OF GROUND WATER SAMPLES <br /> Water samples were collected from MW-I through MW-4, MW-7, VW-3 and VW-4 with a hose <br />' bailer while dedicated disposable plastic bailers were used to sample the remaining wells after <br /> allowing the wells to achieve a minimum 80%recovery of the pre-purge water volume Each water <br /> sample was transferred into laboratory-supplied 40-m1 VOA vials containing 0 5 ml 18% <br />' hydrochloric acid as a sample preservative,the sample from MW-4 was also transferred into a 1-liter <br /> amber bottle without preservative After collection, the samples were properly labeled, placed in a <br /> chilled container and transported under cham-of custody to Cal Tech Environmental Laboratories <br />' (CTEL), a California Department of Health Services (DHS)-certified analytical laboratory for <br /> analysis The samples were analyzed for <br />' C Total petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with EPA <br /> Method 8015M, and <br />' • Volatile organic compounds (VOCs), including benzene, toluene, ethylbenzene and total <br /> xylenes (BTEX) with fuel oxygenates, including di-isopropyl ether (DIPE), ethyl tertiary- <br /> butyl ether(ETBE),methyl tert butyl ether(MTBE),tertiary-amyl methyl ether(TAME)and <br /> tertiary butyl alcohol (TBA) in accordance with EPA method 8260B Full Scan <br /> In addition, ground water sample MW-4 was analyzed for diesel (TPH-d) in accordance with EPA <br /> Method 8015M <br /> 3.0 FINDINGS <br />' Ground water elevation and flow direction were inferrea from field data Hydrocarbon-impact to <br /> ground water was quantified by laboratory analysis of the ground water samples <br /> 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION <br /> IThe elevation of ground water in each well was calculated by subtracting the depth to ground water <br /> from the surveyed casing elevations (Table 1) Depths to ground water ranged from 35 97 feet to <br /> 36 67 feet below the tops of the well casings The average ground water elevation at the site was <br /> 23 51 feet below mean sea level (MSL), indicating an average decrease of 2 61 feet below rMSL <br /> between the second quarter 2003 and third quarter 2003 monitoring events The ground water levels <br /> were as high as approximately 19 feet above the screened intervals in wells MW-1 through MW-4 <br /> and MW-7 <br /> Advanced GeoEnvironmen,tal,Inc <br /> I <br />