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Site Background Information AGE-NC Project No. 02-0950 Page 2 of 4 STRATIGRAPHY Generally, gray, orange-brown to dark-brown, dry silt with sand and gravel (fill material) was encountered from surface grade to approximately 6 feet below surface grade (bsg). Light yellow- orange-brown to dark brown, damp to moist clays, clayey silts, and clayey sands were encountered from approximately 6 feet to 21 feet bsg. Brown, blue-gray to dark-gray, saturated, fine to coarse sand and silty sand were encountered from approximately 21 feet to 29 feet bsg,but to almost 35 feet bsg in the area of MW-2. Gray to blue-gray,moist to saturated clay with medium to high toughness and plasticity was encountered from approximately 29 feet to 36 feet bsg. Blue-gray to green-gray, saturated silt was encountered from approximately 36 feet to 49 feet bsg in soil boring B4. Green- gray, saturated fine sand was encountered from approximately 49 feet bsg to total depth in soil boring B4. PREVIOUS SITE ASSESSMENTS On 15 and 16 October 2002,three soil borings (B1 though B3)were advanced to a depth of 35 feet bsg utilizing a van-mounted Geoprobe 5400 direct-push probing unit equipped with 1.25-inch probing rods,for the collection and analysis of soil and `grab' groundwater samples.After probing to a depth of 25 feet bsg, ground water was found to be at approximately 22 feet bsg. Soil boring B 1 was advanced in the northwest corner of the former UST excavation,soil boring B2 was advanced approximately 5 feet east of the former UST excavation, and soil boring B3 was advanced approximately 10 feet southwest of the former UST excavation. A total of six soil samples were analyzed for the petroleum hydrocarbon products. TPH-g was detected in soil samples collected from all three borings at a maximum concentration of 22,000 milligrams per kilogram (mg/kg) in sample 132-15. TPH-d was detected in soil samples collected from borings BI and B2 at a maximum concentration of 7,500 mg/kg in sample 132-15. BTEX compounds were detected in soil samples collected from all three borings at maximum concentrations of 1.1 mg/kg, 460 mg/kg, 320 mg/kg, and 1,830 mg/kg, respectively, in sample 132-15. Lead was detected by EPA Method 6010B in one soil sample collected in boring B2 at a concentration of 59 mg/kg in sample 132-15. No additional analytes were detected at or above laboratory detection limits in the soil samples analyzed. A grab ground water sample was collected from each of the three borings on 15 and 16 October 2002 and analyzed for the petroleum hydrocarbon products.TPH-g was detected in ground water samples collected from each boring at a maximum concentration of 170,000 micrograms per liter(µg/1) in boring B2. TPH-d was detected in ground water samples collected from borings B 1 and B2 at a maximum concentration of 23,000 µg/l in boring B2. BTEX compounds were detected in ground Advanced GeoEnvironmental,Inc.