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Ile 29 June 2001 AGE-NC Project No 97-0333 ' Page 4 of 5 ' • Ground water flow direction at the site was inferred to be towards the northeast at a gradient of 0 001 or less; due to the low gradient at the site, slight variations in ground water measurements or changes of recharge/discharge of the local ground water could greatly ' modify ground water flow direction • The ground water elevation at the site was within the screened intervals of wells MW-1, MW-2, MW-3,MW-4 and MW-5 which should yield samples fully representative of shallow ' ground water conditions (First Water Zone), ground water elevation was approximately S feet above the screen interval at MW-6 (drowned), but should still yield a sample representative of First Water Zone as defined in Cone Penetrometer Testing Site Investigation -Fourth Quarter 2000, dated 07 February 2001 • Ground water elevation decreased at the site an average 0 40 feet between the January 2001 ' and the April 2001 ground water monitoring events, the decrease of ground water elevation is probably due to seasonal fluctuation ' ■ The core of the dissolved petroleum hydrocarbon plume appears to be located in the area of MW-2 (screened between 12 and 32 feet bsg) and MW-6 (screened 20 to 45 feet bsg) and is impacted by TPH-g, BTEX, and MTBE ' • Substantial concentrations of dissolved TAME have previously been detected in water samples collected from well MW-1 and a grab ground water sample collected from P-3 indicating that there is a limited area impacted with TAME in ground water in the area assessed • Substantial concentrations of PCE were detected in water samples collected from MW-4, PCE is a chlorinated solvent often associated with dry cleaning operations Substantial concentrations of chloroform were detected in water samples collected from MW-1 and MW-2 ' It is possible that 1,2,3-tnchlorobenzene, hexachlorobutadiene, and tnchloroethene (TCE) were present in water samples but not detected (masked) due to abnormally high laboratory ' detection levels ■ The vertical extern of dissolved petroleum hydrocarbons is not known at the site, Figures 5 and 6 in Cone Penetrometer Testing Site Investigation - Fourth Quarter 2000, dated 07 February 2001 depict dissolved petroleum hydrocarbon-impact at depths up to 137 feet bsg, ' The lateral extent of the dissolved petroleum hydrocarbon plume is not fully defined toward the northwest, north, east and southeast of the current area bound by wells MW-1 through MW-6 (Figures 4 and 5) 4dtancrriGeoFinirnnmudal [mL