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• • 08 April 2014 AGE Project No. 07-1537 Page 5 of 6 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 1/4-inch Teflon® tubing from the soil-vapor well. The purge canister will be attached to the end of the stainless steel sampling manifold while the sample canisters will be attached to the tee-fitting between the %-inch Teflon® tubing and purge container. Teflon® tape will be placed on the threads of each open fitting of the manifold assembly prior to attaching the %-inch Teflon® tubing and sampling and purge canisters (Figure 4). Each canister's initial vacuum will be measured and recorded between -26 and -30 inches of mercury (in hg). Shut-in 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 shut-in test is performed for approximately 10 minutes on each assembly. Each soil-vapor monitoring well location will be isolated from ambient air by enclosing the borehole, tubing and manifold/canister assembly in a 100-liter shroud. Isopropyl alcohol (IPA) is emitted into the shroud surrounding the well borehole, tubing and manifold/canister assembly and acts as a tracer gas to evaluate if leaks in the sampling apparatus have allowed infiltration of ambient air. Upon achieving a successful leak test, the purge canister valve will be opened for a period of time to allow the three calculated volumes of air to be purged (Appendix B). The purge vacuum gauge will be monitored to ensure a proper decrease of vacuum purged. Upon achieving the targeted purge volume, the purge canister valve will be closed and the sample canister valve opened. The initial pressure and time is recorded. Upon reaching at least -5 in Hg or less, the sample canister valve will be closed and final pressure and time recorded. The sampling port on the sampling canister will be capped with a brass end-cap. After collection of the sample, soil-vapor from the polyethylene tubing will be monitored for the presence of volatile organics using a PID. 3.4. EQUIPMENT DECONTAMINATION Prior to use, all sampling tools used for sample collection will be thoroughly rinsed with clean water after being washed with a solution of Alconox. All probing rods will be cleaned prior to advancement at each probe boring location. Advanced GcoEnvironmental Inc.