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' 14 December 2005 • AGE-NC Project No 98-0533 Page 2 of 4 the wells to achieve a minimum 80% recovery of the pre-purge water volume The samples were ' transferred into laboratory-supplied 40-m1 EPA-approved VOA vials containing 0 5 ml 18% hydrochloric acrd as a sample preservative The sample vials were then labeled with the monitoring well designation,date,time of sampling and the sampler's initials The samples were transported in , a chilled container under chain of custody to MAI for analysis The samples were analyzed for ' - Total petroleum hydrocarbons quantified as aviation gasoline (TPH-ag) in accordance with EPA Method 5030/8015M, ' - Benzene,toluene,ethylbenzene and xylene(BTEX)and methyl tertiary-butyl ether(MTBE) in accordance with EPA Method 262'6, I - Fuel oxygenates - tertiary butanol (TBA), di-isopropyl ether (DIPS), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and MTBE in accordance with EPA Method ' 8260B, and Ethylene dibromide (EDB) and 1,2 dichloroethane (1,2 DCA) in accordance with EPA method 8260 At the request of the EHD,a ground water sample from the on-site domestic well was also collected ' and analyzed To ensure that formation water was being produced, water was allowed to run out of the well for approximately 20 minutes,which was long enough to automatically turn the well pump ' on Ground water was poured directly into the 40-m1 VOA vials from a valve at the well head ' 3.0. FINDINGS Ground water elevation, ground water gradient and flow direction were determined from field data, ' ground water were assessed by laboratory analysis of ground water samples 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION The elevation of ground water in each of the three monitoring wells was calculated by subtracting ' the depth to ground water from the surveyed relative casing elevations (Table 1) Depths to ground water ranged from 81 30 feet to 81 90 feet bsg Depth to ground water dropped an average of 9 77 feet since the previous monitoring event in May 2002 Ground water elevations at the site ranged ' from 24 54 feet(MW-1)to 24 90 feet(MW-3)below mean sea level The ground water gradient was . calculated to be 0 005 ft/ft directed towards the east-northeast Figure 3 illustrates the contoured IAdvanced GeoEnvironmental,Inc I