WORK PLANS - Laserfiche WebLink

Home Browse Search

The sampling procedure requires one end of the tubing to be been inserted into the ground a bentonite seal must be slipped over the sampling port and the other end over the formed between ambient air and the sample air. The canister nozzle or flow meter(if required) to acquire an air- bentonite must be hydrated and create an air tight seal tight connection. The valve should be opened at this time around the probe. If required IPA can be placed on the joints and the initial pressure should then be recorded to verify that of the vapor probe and analyzed for in the sample to ensure the Summa canister is under vacuum. The Summa canister that ambient air is not diluting the soil vapor survey samples. is allowed to collect the soil vapor sample at a predetermined duration. After the sample has been Once the sample apparatus has been set up new tubing will collected record the final vacuum reading (approximately five be connected to the inlet of the SKC sample pump. The pounds per square inch (psig))to ensure that the flow meter pump operates at a low flow purge rate of 200 milliliters per was working properly, if applicable. Immediately following minute to prevent air stripping of contaminants from the soil. the sample collection, complete sampling information is Once three volumes have been evacuated (minimum 4.2 recorded on the label on the air sampling canister(e.g., minutes of sample time) a sample can be collected. sample ID, date, time, location, and temperature). The Verification with a PID will determine when the maximum sample is placed in a non-refrigerated, dry cooler with concentration is obtained and a sample should be collected. sufficient packing to ensure against damage during If measurable concentrations are not obtained with the PID transport. Cooling samples will cause condensation of any after 7 purge volumes (10 minutes) a sample should be moisture within the air sample, thereby distorting laboratory collected. Once a sample has been determined to be analysis. collected new tubing will be placed on the effluent of the sample pump running to the Tedlar bag, which should be Summa canister samples are subject to hold times of filled to 3/4 of volume capacity. Caution should be taken not typically 30 days and with some compounds a more rigid to overfill the sampling bag. The sample is placed in a non- hold time of 14 days is required. refrigerated dry cooler with sufficient packing to eliminate damage during transport. Cooling samples will cause SOP-13 condensation of moisture within the sample, thereby SOIL VAPOR SAMPLING: SYRINGE SAMPLING distorting laboratory analysis. TECHNIQUE To minimize the potential for cross-contamination between Prior to vapor sampling, the vacuum system must reach a air samples new polyethylene tubing will be used for every stabilized air flow(cubic feet per minute) for approximately sample. 15 minutes. Prior to the actual collection of the vapor sample, the following data is recorded: air flow, temperature, Vapor samples are also subject to the same hold times and and pressure at collection ports and gauges. must be stored as stated in SOP-10. The sampling equipment consists of a clean, 100cc, gas- SOP-15 tight syringe and silicone septa. SOIL GAS SAMPLING FROM DIRECT PUSH SOIL BORING: "TEDLAR" BAG SAMPLING TECHNIQUE The sampling ports are brass connections, fitted with silicone septa, and threaded into a tapped hole in the system piping. To obtain soil gas samples from a direct push drill rig, Samples are collected by inserting a clean syringe into the advance a discreet sampling rod with a 6-inch retractable septum and the plunger actuated several times. Each vapor screen to the desired sample depth. Release the syringe should be purged of three syringe volumes before sample screen cover from the screen and retract the rod 6- collecting the sample. On the fourth purge, the plunger is inches. Place a dry bentonite powder layer in the annulus to extracted slowly until the syringe is filled with a gas sample, seal the borehole from surface air interference. Tamp the then the syringe is withdrawn and the needle immediately bentonite powder, place a hydrated bentonite layer in the plugged with a silicone stopper. The sample should be annulus, and follow with a second dry bentonite layer. Attach placed in a non-refrigerated, dry cooler with sufficient the soil gas sampling diaphragm pump to the rod casing packing to eliminate breakage during transport. Cooling using polyethylene tubing. samples will cause condensation of moisture, thereby distorting laboratory analysis. The sampling equipment consists of a TedlarTm bag (available in 1, 3, 5, and 10 liter sizes), a diaphragm pump, Duplicate air samples should be collected as in SOP-10. and 3/16-inch-diameter polyethylene tubing (approximately 1 Vapor samples are also subject to the same hold times and foot long). The TedlarTm bag should be fitted with an integral must be stored as stated in SOP-10. valve for filling and sealing the bag after sampling. The diaphragm pump inlet and outlet are fitted with 3/16-inch SOP-14 hose barbs for attaching the sample tubing. A sample label SOIL VAPOR SURVEY SAMPLING: "TEDLAR" BAG with the sample number and date and time of sample SAMPLING TECHNIQUE collection is prepared and placed on the TedlarTm bag. The sampling equipment consists of a"Tedlar" bag The sampling procedure requires one end of the tubing be (available in 1, 3, 5, and 10 liter sizes), an SKC universal slipped over the direct push drill rod sample port hose barb sample pump, soil vapor probe, and 1/4-inch-diameter and the other end over the diaphragm pump inlet hose barb polyethylene tubing (approximately three feet long). to form an air-tight connection. The sampling pump is then started and the pump is purged for 1 minute with the vapor A Roto-hammer or slam bar is used to obtain a three foot to be sampled. Following purging, the discharge of the hole into the ground area, where the soil vapor sample will pump is then connected to the TedlarTm bag using a section be collected. Once the hole has been formed the soil vapor of 3/16-inch tubing. The pump is restarted and the bag is probe will be inserted into the hole and advanced the opened and allowed to fill to approximately 3/4 of its remaining two feet, five feet total below ground surface capacity. Caution should be taken not to overfill the (bgs), with the use of either a slide hammer, using a tee sampling bag. The sample is placed in a non-refrigerated adapter and using physical force. Once the vapor probe has dry cooler with sufficient packing to prevent damage during