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19 October 2012 AGE-NC Project No. 97-0312 Page 6 of 22 mg/kg, respectively. Additionally, grab groundwater samples were collected from borings B-14, B-15 and B-17. TPH-g, TPH-d, MTBE and BTEX were detected in each sample. MTBE concentrations ranged from 6.4 pg/I in the sample from B-14 to 9,700 pg/I in the sample from B-17. • September 1999 - Twelve soil borings were advanced at the site to further define the lateral and vertical extent of hydrocarbon-impacted soil. Borings B18 through B29 were advanced to vertical depths between 30 and 70 feet bsg. TPH-g was detected in only one sample (B21-10) at a concentration of 6.7 mg/kg. TPH-d was detected in 11 of the 39 samples analyzed at concentrations as high as 660 mg/kg (B21-10). Benzene was detected in four of the 39 samples at concentrations as high as 0.057 mg/kg. Toluene was detected in sample B21-10 at a concentration of 0.091 mg/kg. Ethylbenzene and xylenes were not detected in the soil samples analyzed from the September 1999 drilling. MTBE was detected in three of seven soil samples analyzed by EPA Method 8260 at concentrations as high as 2.7 mg/kg. Other oxygenates were not detected. • 30 July 2002- Groundwater monitoring well UST-1 was destroyed by over-drilling to total depth. Following over-drilling,the boring was backfilled to surface grade with portland cement in accordance with EHD regulations. • 06 December 2002 - One groundwater monitoring well (UST-7) was installed to a depth of 90 feet bsg; the well screen of UST-7 was recorded as placed between 85 feet and 90 feet bsg. Soil samples were collected at 25 feet bsg and 45 feet bsg. The physical properties of soil samples MW7A-25 and MW7A-45 were described as a brown silt and a brown clay with specific gravity of 2.76 and 2.75, permeability of 6.2 x 10' and 8.4 x 10-8, porosity of 49.96% and 43.99%, pH of 7.6 and 7.5, and total organic content of 1.8% and 2.2%, respectively. Tetrachloroethene was detected in the groundwater sample collected from UST-7 at a concentration of 1.3 pg/I. No other analytes of concern were detected. • 07 September 2005 - Groundwater monitoring wells UST-8 and UST-9 were completed using 2-inch diameter PVC casing; 0.020-inch slotted screen was installed from approximately 65 feet to 75 feet bsg in well UST-8, and from approximately 95 feet to 105 feet bsg in well UST-9, with blank casing extending to — the surface in both borings. Generally, clayey silt was encountered to 70 feet bsg and silty and sandy soil (sandy silt, silty sand, and sand) were encountered in the borings to 105 feet bsg (total depth of UST-9). TPH-g and TPH-d were detected at concentrations ranging from 1.7 mg/kg (UST9-100) to 320 mg/kg (UST9-25) and 14,000 mg/kg (UST8-10 and UST9-25)to 16,000 mg/kg (UST9-10), respectively in the soil samples collected from UST-8 and UST-9. BTEX constituents were also �-' detected in the soil samples UST9-10, UST9-25, UST9-90 and UST9-100 with maximum concentrations found in sample UST9-25 at 2.6 mg/kg benzene, 6.0 83 mg/kg toluene, 41 mg/kg ethylbenzene and 247 mg/kg total xylenes. Advanced CeoEnvironmental,Inc. V