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} 12 August 2003 AGE-NC Project No. 03-1035 Page 5 of 7 4.4. EQUIPMENT DECONTAMINATION AND BORING ABANDONMENT Prior to sample collection, soil sampling equipment was thoroughly rinsed with clean water after washing with a solution of Alconox. Geoprobe rods were thoroughly cleaned prior to soil probe boring advancement. Following soil and ground water sample collection, each probe-boring location was backfilled to surface grade with Portland cement. 5.0. FINDINGS Soil descriptions (lithologies), were determined from field data. Hydrocarbon impact to soil was characterized from field and laboratory analytical data. 5.1. STRATIGRAPHY The soil boring samples indicate that the vertical soil profile consisted of a reddish- to yellowish- brown silty fine sand and fine sand from the surface to approximately 25 feet bsg. The clay content is generally low(<5%),but can range up to approximately 20%. A reddish-to yellowish-brown silt with generally low toughness and plasticity occurs 'from approximately 25 to 40 feet bsg and a reddish-brown clayey silt with high toughness and low to moderate plasticity occurs from 40 feet bsg to total depth. A faint petroleum hydrocarbon-like odor was noted only in the soil sample collected from probe boring B-1 at 9 feet bsg. Organic vapors were detected with the PID in sample B 1-14' at 2.0 parts �. per million(ppm), sample B1-24 `at 1.0 ppm, and sample B3-50 at 9.1 ppm. Depth to ground water was estimated at 42 feet bsg in soil boring B-3. 5.2 ANALYTICAL RESULTS OF SOIL AND GROUND WATER SAMPLES Five soil samples from boring B-1 and five soil samples from boring B-2 were submitted to CTEL on 29 May and 02 June 2003, respectively, for analysis. Toluene, ethylbenzene and xylenes were detected in sample B1-24 at 0.042 milligrams per kilogram (mg/kg), 0.10 mg/kg and 0.81 mg/kg, respectively. In addition, the fuel additive MTBE was detected in samples B1-14 and B1-24 at concentrations of 0.012 mg/kg and 0.050 mg/kg,respectively. However, prior to removal in 1989, the former gasoline UST at the site was reportedly out-of-service for 20 to 25 years, which would -+ Advanced GeoEnvironmental,Inc.