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�a W M 30 July 2008 Ei AGE-NC Project No . 99-0682 Page 9 of 13 f l v pore pressure. Hydrogeologic Unit 7 (HU7) - extends from 161 feet to 177 feet bsg; the unit is characterized by a thick sand interval on the eastern edge of the site which appears to transition to interbedded stiff fine grained soil, clays and silts towards the west. Pore pressures in HU7 range between low pressures in the sand interval to moderately low to moderate in the finer-grained soils . Hydrogeologic Unit 8 (HU8) - extends from 177 feet to 190 feet bsg; HU8 consists primarily of silt and clay, the unit is characterized by moderately low to moderate pore pressures . Hydrogeologic Unit 9 (I-1U9) - extends from 190 feet to 195 feet bsg; the unit is a silty sand to sandy silt layer characterized by low and some moderate pore pressures . Hydrogeologic Unit 10 (HUl0) - extends from 195 feet to 200 feet bsg; HU10 is predominately silt and clay; the unit is characterized by moderate and some low pore pressures . 3 .3 . ANALYTICAL RESULTS OF GROUND WATER SAMPLES Ten grab ground water samples were collected from borings CPT-6, CPT-7, CPT-8, B-5 and B-6 from two water bearing zones (67 to 75 feet bsg and 124 to 130 feet bsg); samples were analyzed for the constituents listed in Section 2. 1 .2. Water Bearing Zone: 67 to 75 feet bsg TPH-g was detected in samples CPT7-75, CPT8-70, and B6-75 at concentrations of 1 ,800 micrograms per liter (µg/l), 90,000 µg/l and 3,300 µg/1, respectively. TPH-dwas detected in samples CPT7-75, CPT8-70, and B6-75 at concentrations of 4,800 gg/l, 8,400 µg/1 and 5 ,600 gg/l, respectively. Two or more BTEX compounds were detected in samples CPT7-75, CPT8-70, and 136-75 at maximum concentrations of 3,300 µg/1 benzene, 4,200 µg/1 toluene, 3 ,000 µg/1 ethylbenzene, and 13, 100 µg/1 total xylenes in sample CPT8-70 . TAME and 1 ,2-DCA were detected in sample CPT8-70 at concentrations of 290 µg/1 and 82 µg/l, respectively. Chemicals of concern (COC) within this water bearing zone were not detected at or above detection limits in the samples collected from the CPT-6 and B-5 locations. Advanced GeoEnvironmental, Inc.