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' 15 November 2005 i AGE-NC Project No 01-0877 ' Page 2 of 4 ' analysis(VOA)vials containing 0 5 ml 18%hydrochloric acid solution as a sample preservative,and one 1-liter amber bottle without 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 State of California Department of Health Services (DHS)-Environmental Laboratory Accreditation Program certified(#2424)analytical laboratory,for analysis The samples were analyzed for ' 0 Total petroleum hydrocarbons quantified as gasoline(TPH-g),diesel(TPH-d),and motor oil (TPH-mo) in accordance with EPA Method 8015 Modified, and ' 0 Benzene,toluene,ethylbenzene, and total xylenes (BTEX) and volatile organic compounds 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 8260 ' 3.4. FINDINGS ' ! Ground water flow direction, elevation, and gradient were determined from data collected in the field The hydrocarbon impact to ground water was quantified by the laboratory data obtained from ' the ground water samples ' 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION At the time of the July 2005 sampling event, depths to ground water ranged from 25 63 (MW-3)to 26 32(MW-4)feet below the tops of the well casings(Table 1) The average ground water elevation at the site was approximately 15 92 feet below mean sea level (MSL), which indicates an increase in the static ground water elevation of approximately 0 23 feet since the last monitoring event Ground water flow was inferred to be towards the northeast at an average gradient of 0 003 foot/foot Figure 3 illustrates the contoured ground water elevations as measured on 22 July 2005 During the July 2005 monitoring event, ground water levels were within the screened interval of each well, indicating that the wells were screened properly to yield representative ground water samples 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in all water samples at concentrations ranging from 39,000 micrograms per liter • (µg11) in sample MW-4 to 470,000 µg/1 in sample MW-3 TPH-d was detected in all water samples Advancer!GeoEnvironmentsl,Inc '