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' 2 • 1 December 2001 ' AGE-NC Project No 98-0433 Page 2 of ' 2 2 GROUND WATER SAMPLE COLLECTION ' Prior to the collection of ground water samples, the depth to ground water was re-measured in each well to ensure that a minimum of 80%ofthe initial water volume had recharged Water samples were then collected from each well using the pre-dedicated disposable bailer The water was transferred ' into one 1-liter amber bottle and three chilled 40-m1 volatile organic analysis(VOA)vials containing 0 5 ml hydrochloric acid(18%) as a sample preservative After collection, the samples were Iabeled and placed in a chilled container for transportation under chain-of-custodyto McCampbell Analytical ' Laboratories (MAI), a DHS-certified analytical laboratory Each sample was analyzed for • Total petroleum hydrocarbons quantified as gasoline and diesel (TPH-g and TPH-d) in Iaccordance with EPA Method 8015 Modified, • Benzene, toluene, ethyl benzene and total xylene(BTEX) in accordance with EPA Method I 8020, • Oxygenated fuel additives - methyl butyl ether (MTBE), tertiary butyl alcohol (TBA), di- isopropyI ether (DIPE), ethyl tertiary butyl ether (ETBE) and tertiary amyl methyl ether pe (TAME) in accordance with EPA Method 8260 Modified 3.0 FINDINGS - I Ground water elevations were determined by subtracting the measured depths-to-water• from the surveyed casing elevations Ground water flow directions were determined by contouring the water elevations on a scaled site plan (Figure 3) The impact of the unauthorized release on ground water Iwas quantified by laboratory analysis of samples collected during the quarter 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION Depth to ground water at the site on 05 October 2001 ranged from 20 26 to 22 04 feet below well casing tops The ground water elevations at the site ranged from 36 35 feet to 36 90 feet above mean sea level (mst) The data indicates an average decrease of the ground water elevation at the site of 1 6 feet since the previous quarterly monitoring event Ground water flow direction and gradient were calculated from the October 2001 gauging data The flow direction was determined to be in a westerly direction,from well MW-6 toward the former UST location and north away from the former UST area with a hydraulic gradient of approximately 0 002 feet/feet The depth to ground water and calculated elevation date are presented in Table 1 Figure I3 illustrates the contoured ground water elevations Advanced GeoEnviroamental,Inc I