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08 June 2010 AGE-NC Project No. 01-0839 Page 4 of 5 Clean and dry direct-push soil boring rods and a post-run tubing (PRT) system assembly will be prepared for advancement by installing new disposable O-rings on the PRT expendable point holder (the PRT adapter) and the disposable drive point. The boring rod with the PRT assembly will be advanced to the target sampling depth of 5 feet bsg for each soil vapor sampling location, then the boring rod will be retracted approximately 12 inches. The PRT adaptor will then be connected to a chemically resistant and disposable polyethylene '/4-inch tubing. The PRT adaptor and tubing will be inserted through the hollow boring rods down to the PRT assembly attached to the lead probe rod and seated to the adaptor into the top of the PRT probe assembly. Hydrated bentonite will be placed around the drive rod at ground surface to prevent ambient air intrusion. A minimum of 20 minutes equilibrium time will be allowed at each soil vapor boring location prior to sample collection. 3.2 SOIL-VAPOR SAMPLE COLLECTION AND ANALYSIS One-liter Summa sampling and five-liter Summa purge canisters will be used to collect each soil- vapor sample. The sampling and purge canisters will be connected together with a dedicated and serialized sampling inlet manifold.The sampling inlet manifold will consist of a vapor-tight valve; a particulate filter; a calibrated flow restricter, calibrated to 200 milliliters per minute(ml/min); a stainless steel tee-fitting;two vacuum gauges at either end of the flow controller and connections for both purge and sampling canisters (manifold assembly). The manifold assembly will be attached to the tubing from the direct-push soil probe rods.The purge canister will be attached to the end of the sampling manifold while the sample canisters will be attached to the tee-fitting between the PRT and purge container. Teflon®tape will be placed on the threads of each open fitting of the manifold assembly prior to attaching the PRT and sampling and purge canisters. Each canister's initial vacuum will be measured and recorded between-27 and-9 inches of mercury (in hg). Leak tests will be performed on each assembly by attaching and securing the sample and purge canisters to the manifold and opening the valves on the purge canister and the manifold. The leak test will be performed for approximately 10 minutes on each assembly. Each soil-vapor boring location will be isolated from ambient air by enclosing the borehole,tubing and manifold/canister assembly in clear plastic sheeting supported by a Type-1 wooden traffic barricade and weighted at the surface.Isopropyl alcohol(IPA)as a liquid will be placed in a stainless steel bowl within the plastic structure and allowed to volatilize into the air enclosed within the Advanced GeoEnvironmental,Inc.