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Passive Soil Gas and Subslab Installation and Retrieval Standard Operating Procedure (SOP) Instructions for Placement of Passive Soil Gas (PSG) Sampler IMPORTANT-Sampling Depths Greater than 12-inches Wire length: The standard wire length is intended for placement in Subslab or max depth of 12-inches. For deeper installations beyond 12-inches, additional wire or braided fishing line is required to place sampler at desired depths. 1. Remove a Beacon PSG Sampler(a rugged,borosilicate glass vial containing two sets of hydrophobic adsorbent cartridges) and unwind the retrieval wire wrapped around it. Holding the capped end of the vial in one hand, pull the wire tight(to straighten it)with the other hand. 2. Remove the solid cap on the Sampler Vial and replace it with a Sampling Cap (a one-hole cap with a screen meshing insert). Store the solid cap in the Cap Storage Container. 3. Obtain approximately 1 ft by 1 ft sheet of aluminum foil and crumple into a ball. Wrap sampler retrieval wire around the ball. With the screened-capped-end pointing down into the hole, lower the Sampler into the soil vapor well until the aluminum foil ball rests on top of soil vapor well. Be sure to place the sampler %2 to 1-inch above the bottom of the vapor well to minimize contact with soil matrix. Surface Seal Subslab or asphalt covered surfaces: Tamp down the aluminum foil ball with sampler wire wrapped around it over the top of the hole /soil vapor well. Use the dowel to ensure it is pushed down approximately 1/4" or more below grade. Be sure that no wire or aluminum foil sticks up. Prepare ready mix concrete patch and place on top of the compacted aluminum foil so that it is flush with grade. The vapor well is now sealed at the surface. Mark the surface with colored marking spray paint or other method. Soil or uncovered surfaces: Tamp down the aluminum foil ball with sampler wire wrapped around it over the top of the hole/soil vapor well. Use the dowel to ensure it is pushed down approximately 1/4" or more below grade. Be sure that no wire or aluminum foil sticks up. Use a hammer to collapse native soils above the foil plug. Mark the surface with a small flag or colored marker spray paint. Documentation and Field Report Fill in the provided Chain of Custody record: (a) sample-point number; (b) date and time of emplacement; and(c) other relevant information(e.g., soil type,vegetation,proximity to potential source areas). Be sure to mark the sample location on a map and take detailed notes (i.e., compass bearings and distances from fixed reference points or GPS coordinates). IMPORTANT: PLEASE MARK TIME OF PLACEMENT FOR CONCENTRATION REPORTING Page 6 of 8