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' 25 November 2005 . AGE-NC Project No 95-0167 Page 2 of 4 ' water sample was transferred into three 40-milliliter (ml) volatile organic analysis (VOA) vials containing 0 5 ml 18% hydrochloric acid solution as a sample preservative After collection, the samples were properly labeled,placed to a chilled container,and transported under chain of custody ' to Cal Tech Environmental Laboratories (CTEL), a California Department of Health Services (DHS)-certified analytical laboratory to Paramount, California The samples were analyzed for • Total petroleum hydrocarbons quantified as gasoline (TPH-g) In accordance with EPA Method 8015 Modified, and ' Benzene, toluene, ethylbenzene, and total xylenes (BTEX) and the fuel additives methyl tertiary-butyl ether MTBE, di-isopropyl ether (DIPS), ethyl tertiary-butyl ether (ETBE), tertiary-amyl methyl ether(TAME),tertiary-butyl alcohol(TBA), 1,2-dibromoethane(EDB), and 1,2-dichloroethane (1,2-DCA) in accordance with EPA Method 8260B ' 3.0. FINDINGS Ground water flow direction,elevation,and gradient were determined from data collected in the field iduring the March 2005 quarterly monitoring event The hydrocarbon impact to ground water was quantified by laboratory data obtained from ground water samples ! An error was discovered in the surveying data supplied by Morrow Surveying on 05 October 2004 The corrected casing elevation for MW-2 was used to recalculate ground water elevations from the ' 3" and 4t`quarterly monitoring events in 2004 Updated ground water gradient and flow maps for these quarters are included in Appendix D, correct surveying Exhibit is included in Appendix E ' 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION ' On 25 March 2005,depths to ground water ranged from 13 48 feet(MW-5 and MW-7)to 14 61 feet (MW-2) below the tops of the well casings Ground water elevations at the site averaged i approximately 2 98 feet below mean sea level (MSL), indicating an average elevation Increase of ' 2 6 feet since the last monitoring event In December 2004 (Table 1) During this monitoring event, ground water was within the screened interval of each well,thus producing an accurate sampling of the first encountered ground water The ground water flow direction was determined by plotting and contouring the ground water elevation data At the time of the March 2005 monitoring event, ground water at the site was idetermined to be flowing east-northeast under a hydraulic gradient ranging from 0 004 ft/ft in the . western portion of the site, to 0 002 ft/ft in the eastern portion (see Figure 3) iAdvanced GeoEnvlronmental,Inc i