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' 24 October 2005 . AGE-NC Project No 95-0167 ' Page 7 of 10 to gravelly sand below This zone is characterized by low pore pressures and may be considered a flow unit ' HU2-HU2 extends from approximately 33 feet to 43 feet bsg This zone consists primarily of clay, clayey silt, and silty clay This zone is characterized by generally low pore pressure, except for a high-pressure peak at the bottom of the unit associated with very fine sands or less permeable clayey material HU3 - Extending from 43 feet to approximately 55 feet bsg, HU3 is composed primarily of layers ' of sandy material (sand and fine- to coarse-grained sand) This zone exhibits uniformly low pore pressures and may be considered a flow unit ' HU4 - Extending from 55 feet to approximately 70 feet bsg, HU4 is composed primarily of thin, alternating layers of silty material (silt, and silt with clay) HU5 - Extending from 70 feet to approximately 80 feet bsg, HU5 is composed primarily of layers of sandy material (silty sand, sand, and fine-to coarse-grained sand) This zone exhibits uniformly low pore pressures and may be considered a flow unit 3 3 GROUND WATER GRADIENT AND FLOW DIRECTION On 24 September 2004, depths to ground water ranged from 16 13 feet to 16 94 feet below the tops ' of the well casings Groundwater elevations at the site averaged approximately 5 15 feet below mean sea level (MSL) Ground water was within the screened interval of each well, thus producing an accurate sampling of the first encountered ground water ' The ground water flow direction was determined by plotting and contouring the ground water elevation data The shape of the water table at the time of the September 2004 monitoring event was ' in the form of a mound centered over monitoring well MW-2,with a trough immediately to the west Ground water at the site was determined to be flowing radially outward from the mound under an average hydraulic gradient of approximately 0 012 foot/foot(ft/ft) Figure 5 illustrates the contoured ' ground water elevations as measured on 24 September 2004 3 4 ANALYTICAL RESULTS OF SOIL SAMPLES _ A total of seven soil samples were collected from pilot borings MW-7 and MW-8 and analyzed for ' the constituents listed in section 2 1 1 , no petroleum hydrocarbon constituents were detected at or • above laboratory reporting limits in the soil samples analyzed Advanced GeoEnvironmentsl,Inc