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19 January 2012 AGE-NC Project No. 11-2006 Page 3 of 7 • VOCs in accordance with EPA method 8260B; and • SVOC's in accordance with EPA method 8270. SOIL-VAPOR SAMPLE COLLECTION Soil-vapor samples were collected using a Geoprobe soil-vapor sampling assembly from borings V1 and V2 at depths of 5 feet bsg. An expendable vapor point was placed into a point holder at the bottom of an assembly of 1.25-inch diameter hollow rods.The assembly was then advanced to the specified depth (i.e. 5 feet bsg) and retracted approximately twelve inches in order to disengage the bottom expendable point and expose a column of strata from which soil-vapor could be extracted. Single use, '/4-inch diameter disposable polyethylene tubing was then attached to a tubing adapter equipped with an O-ring to ensure a vacuum-tight seal. The adapter assembly was lowered through the center of the hollow drive rods to the specified depth and secured by threading into the expendable vapor point holder. Above ground, the surface around the soil-vapor sampler was sealed with bentonite powder and hydrated to prevent ambient air intrusion. Soil- vapor sample collection was conducted using 1-liter Tedlar bags. To ensure that a reliable soil-vapor sample was collected with no ambient air breakthrough down the probe rod, AGE erected a plastic enclosure over the probe rod, and applied an appropriate amount (approximately 6 to 8 ounces) of Isopropyl Alcohol (IPA) as a tracer to adequately wet a towel; the wetted towel was completely wrapped around the base of the probe rod where it contacted the surface and the bentonite seal. The end of the polyethylene tubing was attached by a two-way inlet port to a Tedlar bag placed inside an SKC Vac-U-Chamber (lung box) vacuum chamber. A vacuum pump attached to a purge port of the vacuum chamber was then used to purge the exposed soil column, through the sampling tubing and inlet port, until at minimum, three volumes of soil-vapor and ambient air were evacuated through the sampling system. The vacuum chamber was sealed and the vacuum pump was then attached to the vacuum outlet port of the chamber. Vacuum was applied to the chamber to create negative pressure around the Tedlar bag, which inflated and allowed the soil-vapor sample to enter directly into the bag via the inlet port. When the sample was collected, the negative pressure in the chamber was reduced and the sample bag was sealed, labeled, logged on a chain of custody form, and placed into a dry cooler (room temperature). All of the collected soil-vapor samples were delivered to CTEL and analyzed for the following constituents: • TPH-g in accordance with EPA Modified Method TO-3; and • BTEX and Isopropyl alcohol (IPA)in accordance with EPA Modified Method TO-17. Advanced GeuEnvironmental,Inc.