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17 February 2006 AGE-NC Project No. 05-1256 Page 3 of 10 site by AGE utilizing a van-mounted Geoprobe 5400 direct-push probing unit equipped with _ 1.25-inch probing rods. The borings were advanced to depths of 25 feet and 26 feet bsg. A total of seventeen soil samples were analyzed for petroleum hydrocarbon products. TPH-g was detected in soil samples collected from borings B 1 through B3 at concentrations as high as 29 mg/kg,in sample B3-20;MTBE was detected in all soil samples except B5-20 and B6-25 at a concentrations as high as 25 mg/kg (B3-20); JTAME was detected samples B1-15, 131-25, 132-15, and B3-15 at concentrations as high as 0.038 mg/kg(132-15); and Xylenes were detected in soil sample B2-25 at a concentration of 0.022 mg/kg. Grab ground water samples were collected from first-encountered ground water from soil borings B 1 through B6 and analyzed for petroleum hydrocarbon products. TPH-g was detected in ground water samples BI through B3 at concentrations as high as 86,000 micrograms per liter (µg/1) in boring 132; MTBE was detected in samples B 1 through B3 and B6 at concentrations ranging from 75 pg/l (B6)to 55,000 µg/1 (B2); TAME was detected in samples Bl through B3 at concentrations as high as 120 µg/l in B1;and BTEX constituents were detected in samples B2 and B3 at maximum concentrations in sample B3 of 110 µg/1 benzene, 390 pg/l toluene, 270 gg/l ethylbenzene, and �r 680 µg/l xylenes. The plume of dissolved MTBE and TPH in ground water is defined to non-detectable levels north of the upgraded dispenser area. 2.3. STRATIGRAPHY From surface grade to approximately 4 feet bsg, dark brown to black, dry to slightly moist organic topsoil was encountered throughout the site, generally underlain by a layer of brown, moist sandy silt and sand to approximately 13 feet bsg. From 13 feet to between 20 feet and 23 feet bsg,brown, dark brown,and gray-brown clayey silt and silty clay were identified. A '/2-foot to 1-foot thick layer of clayey sand and sandy clay occurred throughout most of the southern portion of the site at a depth of approximately 20 feet to 24 feet bsg, underlain by silty sand and sand to the total depth of the borings (25 feet to 26 feet bsg). 3.0. SCOPE OF WORK The proposed scope of work is to assess the vertical and lateral extent of hydrocarbon-impacted soil and ground water at the site. The assessment includes the following tasks: • Permitting and pre-field work activities; • CPT drilling and sample collection; • Laboratory analysis of soil and grab ground water samples; Advanced GeoEnvironmental,Inc.