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r � 31 October 1997 AGE-NC Project No 95-0137 Page 2 of 5 were collected from each well using new, clean, disposable plastic bailers The samples were transferred into 40-m1 EPA-approved VOA vials and into 1-liter amber bottles Samples were stored in a chilled container and transported under chain-of-custody to McCampbell Analytical Laboratories (MAI) in Pacheco, California Each sample was analyzed in accordance with EPA Method 8015-m modified for total petroleum hydrocarbons quantified as gasoline (TPH-g), in accordance with EPA Method 8015-M modified for total petroleum hydrocarbons quantified as diesel (TPH-d), in accordance with EPA Method 8020 for benzene, toluene, ethylbenzene and xylenes (BTE&X)with methyl-tert butyl ether(MTBE), and in accordance with EPA Method 8260 for and MTBE and other oxygenated fuel additives, including tertiary butyl alcohol (TBA), di- isopropyl ether (DIPS), ethyl tertiary butyl ether (ETBE) and tertiary amyl methyl ether(TAME) Additionally, a water sample was collected from monitoring wells MW-1 and MW-2 using disposable plastic bailer The sample was transferred into a 1-liter amber bottle This sample was stored in a chilled container and transported under chain-of-custody to MAI Each sample was analyzed in accordance with EPA Method 6020 for dissolved Iron and Manganese • 3 0. FINDINGS 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION Depth to ground water at the site ranged from 17 75 to 18 60 feet The data indicates an average incl ease of ground water elevation at the site of 1 75 feet since June 1997 Historically, ground water flow direction at the site has varied from northwest to southeast, consistently at a low gradient The gradient for October 1997 was calculated to be 0 0073 ft/ft, with an approximately N 45' W flow direction Figure 3 -Relative Ground Water Elevation illustrates the contoured relative ground water elevations as measured on 01 October 1997 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g was detected in wells MW-1 though MW-5 at concentrations as high as 7,200 parts per billion(ppb, reported as micrograms per liter) TPH-d was detected in wells MW-I through MW-5 at concentrations up to 5,100 ppb (MW-3) Benzene was detected in the sample from MW-2 at 1,200 ppb, toluene was detected in MW-2 at a concentration of 46 ppb Ethylbenzene and xylenes were detected in samples collected from MW-1 • and MW-2 at concentrations as high as 580 ppb (xylenes, MW-2)