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' 07 February 2005 AGE-NC Project No 97-0326 Page 3 of 5 ' 3.0. FINDINGS Ground water elevation, and flow direction were determined from field data Hydrocarbon-impact to ground water was quantified by laboratory analysis of ground water samples 1 ' 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION At the time of the June 2004 sampling event,depths to ground water ranged from 35 00 feet to 37 75 ' feet below the tops of the well casings The depth to ground water (36 10 feet) at well MW-1 was affected by the presence of approximately 0 5 inches of free product, so the depth was recalculated (36 06 feet)utilizing the measured thickness of free product in well MW-1 DH,=Dm - (tg * dgldj ' D,= Corrected depth to water D =Measured depth to water tg= Total thickness of free product (-0 05 foot) , . dg= Density of free product (gasoline at—0 75 g/ml) dw= Density of water (-10 gm/ml) During this monitoring event, the water level was within the screened intervals of all the wells, indicating that the wells are screened properly to yield representative shallow ground water samples Ground water elevation contours based on the data for the June 2004 monitoring event are illustrated on Figure 3 The ground water flow direction was southeast with an average hydraulic gradient of approximately 0 004 feet/feet The gradient and flow direction are consistent with the majority of ' previous monitoring events Utilizing multilevel wells MW-8 and MW-9,the vertical gradient between adjacent screen intervals in successively deeper hydrogeologic intervals can be calculated by determining the difference between ground water elevations(dh)and dividing by the difference of the screen interval midpoints ' (dl) Downward vertical gradients were calculated between HU 1 and HU2,HU2 and HU4,and HU4 and HU6 • ' Advanced GeoEnvironmental,Inc