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I03 August 2005 . AGE-NC Project No 02-0950 ' Page 2 of 4 preservative After collection,the samples were properly labeled,placed in 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,for analysis The samples were ' analyzed for • Total petroleum hydrocarbons quantified as gasoline (TPH-g) and diesel (TPH-d) In accordance with EPA Method 8015 Modified, • Benzene,toluene,ethylbenzene,and total xylenes(BTEX)and fuel additives methyl tertiary- butyl ether(MTBE),tertiary-butyl alcohol(TBA), di-isopropyl ether(DIPE), ethyl tertiary- butyl.ether(ETBE),tertiary-amyl methyl ether(TAME), 1,2-dichloroethane(1,2-DCA),and 1,2-dibromoethane (EDB) in accordance with EPA Method 8260B, and • Lead in accordance with EPA Method 6010B ' 3.0. FINDINGS Ground water elevation, flow direction, and gradient were determined from field data collected on 24 March 2005 The contaminant Impact to soil and ground water was quantified from laboratory analytical data 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION At the time of the March 2005 sampling event, depths to ground water ranged from 16 91 feet (MW-1)to 17 20 feet(MW-2 and MW-3)below the tops of the well casings Ground water elevation ' at the site averaged approximately 9 28 feet below mean sea level(MSL), Indicating an Increase in ground water elevation of approximately 3 feet between December 2004 and March 2005 (Table 1) During this monitoring event,the ground water levels in the wells were at least 2 feet below the tops of the well screens, Indicating that the wells are screened properly to yield representative shallow ground water samples ' The general ground water was Inferred to be flowing toward the northwest under a hydraulic gradient of approximately 0 009 foot/foot (ft/ft) Figure 3 Illustrates the contoured ground water elevations as measured on 24 March 2005 Ground water directions and gradients can vary greatly, as they are ' influenced by seasonal changes to the static water table 1 • ' Advanced GcoEnvironmentai,Inc r