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12 June 2012 AGE-NC Project No. 99-0682 Page 2 of 7 Water Table Zone: 20 to 50 feet below surface grade (bsq) • Depths to ground water within the water table zone ranged between 24.91 feet (MW-1A) below the top of the well casing (btoc) and 26.41 feet (MW-3) btoc (Table 1). Ground water elevations in the water table zone ranged between 11.53 feet(MW-1A)below the North American Vertical Datum (NAVD88)and 11.77 feet (MW-3) below NAVD88. • Utilizing site wells, MW-1A, MW-3, MW-4, MW-5 and MW-6, net ground water flow direction was inferred to be toward the northeast at a calculated hydraulic gradient of 0.004 foot per foot (ft/ft). Figure 3 illustrates contoured shallow ground water elevations as measured on 24 April 2012 on-site. • Total petroleum hydrocarbons quantified as gasoline (TPH-g) were detected in samples collected from wells MW-1A and MW-6 at concentrations of 180,000 micrograms per liter (Ng/1) and 160 pg/1, respectively. • Benzene, toluene, ethylbenzene and total xylenes (BTEX) were detected in the ground water samples collected from well MW-1A at concentrations of 390 Ng/1, 29,000 pg/I, 4,800 pg/I and 31,500 pg/I, respectively. • Lead scavengers 1,2-dichloroethane (1,2-DCA) and fuel oxygenate tertiary-amyl methyl ether (TAME) were detected in the samples collected from well MW-1A at concentrations of 6.6 pg/I and 3.6 pg/1, respectively. • Figure 4 depicts the approximate lateral extent of dissolved chemicals of concern (COC) within the water table zone on-site. Water-Bearing Zone: 60 to 70 feet bsq • Depths to ground water with this water-bearing zone ranged between 25.87 feet (MW-8) btoc and 26.74 feet (MW-11) btoc (Table 1). Ground water elevations ranged between 11.93 feet (MW-8) below NAVD88 and 12.41 feet (MW-10) below NAVD88. • Utilizing wells MW-7, MW-8, MW-9, MW-10, and MW-11, net ground water flow direction was inferred to be towards the north-northeast in the direction of well MW-10, under a calculated hydraulic gradient of 0.003 ft/ft. Figure 5 illustrates contoured ground water elevations within this water-bearing zone as measured on 24 April 2012 on-site and off-site. • TPH-g were detected in samples collected from wells MW-7 through MW-10 at concentrations ranging between 140 dig/l (MW-9) and 120,000 pg/l (MW-8). • BTEX compounds were detected in samples collected from wells MW-7 through Advanced GeoEnvironmental,Inc.