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14 December 2011 AGE-NC Project No. 99-0682 Page 2 of 5 Water Table Zone: 20 to 50 feet below surface grade (bsq) • Depths to ground water within the water table zone ranged between 26.00 feet (MW-1A) below the top of the well casing (btoc) and 27.45 feet (MW-3) btoc (Table 1). Ground water elevations in the water table zone ranged between 12.55 feet (MW-5) below North American Vertical Datum (NAVD88) and 12.81 feet (MW-6) below NAVD88. • Utilizing site wells, MW-1A, MW-2, 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 0.005 foot per foot (ft/ft). Figure 3 illustrates contoured shallow ground water elevations as measured on 20 October 2011 on-site. • Total petroleum hydrocarbons quantified as gasoline (TPH-g) were detected in samples collected from wells MW-1A, MW-2, and MW-6 at concentrations of 290,000 micrograms per liter (pg/1), 110 pg/I and 190 pg/l, respectively. Total petroleum hydrocarbons quantified as diesel (TPH-d)were detected in the samples collected from well MW-1A at a concentration 100,000 pg/I. • Two or more benzene, toluene, ethylbenzene and total xylenes (BTEX) compounds were reported in wells MW-1A, MW-2 and MW-6 and at maximum concentrations of 540 pg/I, 66,000 pg/I, 12,000 pg/I and 74,000 pg/I, respectively, in well MW-1A. • Lead scavengers 1,2-dichloroethane(1,2-DCA), 1 ,2-dibromoethane(EDB), and fuel oxygenate tertiary-amyl methyl ether (TAME) were detected in the samples collected from well MW-1A at concentrations of 23 pg/l, 5.2 pg/I and 9.3 pg/1, respectively. • Figure 5 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 bsg • Depths to ground water with this water-bearing zone ranged between 27.18 feet (MW-9) btoc and 28.01 feet (MW-11) btoc (Table 1). Ground water elevations ranged between 13.24 feet (MW-9) below NAVD88 and 13.76 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 north-northeasterly towards well MW-10, under a calculated hydraulic gradient of 0.004 ft/ft. Figure 4 illustrates contoured ground water elevations within this water-bearing zone as measured on 20 and 21 October 2011 on-site and off-site. • TPH-g were reported in wells MW-7 through MW-11 at concentrations ranging Advanced GeoEnvironmenlal,Inc.