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N . 25 January 2005 AGE-NC Project No 99-0559 Page 3 of 12 The general ground water flow direction for HU1/HU2 was towards the west-northwest and and the ground water flow direction was calculated to be north or northwest in the lower flow units (HU3 to HU6) Approximately six inches or less of free-product has been intermittently observed in well MW-2 and lesser volumes have been detected in well MW-1 and MW-3 The highest concentrations of dissolved total petroleum hydrocarbons quantified as gasoline (TPH-g) and MTBE have been documented in the area of the former UST and approximately 75 feet southwest of the suspected release The highest concentrations of MTBE have been detected in samples from well MW-2 at the former UST release area TPH-g and benzene have been detected at concentrations as great as 870,000 microgram pre liter(µg/1) and 48,000 µg/1, respectively in May 2003 The last samples collected from each of the four shallow wells contain benzene above 6,000µg/1 and TPH-g at concentrations greater than 170,000 µg/1, fiirther MTBE was detected above 2,200 µg11 The highest concentrations of petroleum hydrocarbons detected in the CMT wells at the site were present in the ground water samples collected from wells screened in HU 1 and HU2 at the east edge of the UST area(MW-7) The well MW-8 also had detectable concentrations of BTEX compounds during sampling Variable concentrations of low BTEX values were detected in well MW-5 and moderate concentrations of MTBE were also detected in the upper screen of the well Low to moderate, yet stable concentrations of BTEX compounds were detected in well MW-6, also moderate concentrations of MTBE were also detected in the upper screen of the well MW-6 with lower concentrations detected in the lower screened wells of MW-6 The fuel additives TAME,ETBE and 1,2-DCA were detected in samples from the former UST area, and down-gradient of the UST area (MW-4/MW-6) The vertical extent of impacted ground water, has been defined at the perimeter of the site, the vertical extent of impacted ground water at the western and southern edge of the site are defined by well MW-5, and to a lesser degree by MW-6 The vertical extent of impacted ground water, at the former UST area,has not been defined and extends beyond the vertical depth of well MW-7E The lateral extent of shallow impacted ground water towards the west and southwest,down-gradient of the UST area, has not been defined • Advanced GeoEnvironmental,Inc