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23 August 2012 AGE-NC Project No. 96-0236 Page 2 of 4 3.0. FINDINGS The ground water elevation, flow direction and gradient were determined from field data collected on 27 June 2012. The hydrocarbon impact to ground water was quantified by the laboratory analytical data. Findings include the following: • At the time of the June 2012 sampling event, depths to ground water ranged from 9.38 feet (MW-19) below the tops of the well casings (btoc) to 11.68 feet (MW-5) btoc (Table 2). Ground water elevations at the site ranged from 8.33 feet (MW-8) to 10.25 feet (MW-24) below the North American Vertical Datum (NAVD). • Hydrogeologic Unit 1 (HU1) ground water flow(wells screened between 10 and 30 feet bsg) was inferred to be toward the northeast and to the north at hydraulic gradients between 0.002 foot per foot(ft/ft)and 0.004 ft/ft. The inferred HU1 ground water flow direction and gradient is depicted on Figure 3. • Hydrogeologic Unit 2 (HU2) ground water flow(wells screened between 30 and 50 feet bsg) was inferred to be toward the southwest at hydraulic gradients between 0.0009 ft/ft and 0.005 ft/ft. The inferred HU2 ground water flow direction and gradient is depicted on Figure 4. • Hydrogeologic Unit 4 (HU4) ground water flow (wells screened between 70 and 85 feet bsg) was inferred to be oriented eastward at hydraulic gradients between 0.0008 and 0.001 ft/ft. The inferred HU4 ground water flow direction and gradient is depicted on Figure 5. • Total petroleum hydrocarbons quantified as gasoline (TPH-g) were detected in ground water samples collected from wells MW-7, MW-10B, MW-11A, MW-12, MW-13, MW-14, MW-16, MW-19, DPE1 and DPE-2 at concentrations as high as 42,000 pg/I (MW-10B). The estimated extent of dissolved TPH-g in HU2 is depicted in Figure 6. • Benzene was detected in ground water samples collected from wells MW-10B, MW-11A, MW-12, MW-13, MW-14, MW-16, MW-19, DPE-1 and DPE-2 at concentrations as high as 6,540 pg/I (MW-10B). One or more toluene, ethyl- benzene and total xylene (TEX) constituents were detected in ground water samples collected from wells MW-7, MW-10B, MW-11A, MW-12, MW-13, MW-14, MW-16, MW-19, DPE-1 and DPE-2 at concentrations as high as 1,700 pg/I toluene, 720 pg/I ethylbenzene and 3,800 pg/I xylenes (DPE-1). • 1,2-dichloroethane (1,2-DCA)was detected in groundwater samples collected from wells MW-10B, MW-12, MW-14, MW-16, MW-19, DPE-1 and DPE-2 at concentrations as high as 47 pg/I (MW-10B). Advanced GenEnvirnnmcntal,Inc.