WORK PLANS - Laserfiche WebLink

Home Browse Search

TO E RO E K SOP No.021,REV.1 „ SOIL GAS SAMPLING METHODS ASSOCIATES,INC. PAGE 6 or equivalent sampling tube. To prevent ambient air from entering the canister during sample collection, all connections must be airtight. To collect soil gas samples using this method, the following procedures are used: 1. Confirm the valve is closed and remove the brass cap. Attach the pressure gauge and flow controller(integrated system)to the canister. Attach the soil probe to the sample train with Tygon or equivalent tubing. 2. Open the canister valve, which will allow the evacuated canister to draw in soil gas, and immediately record the canister pressure reading and time. 3. Monitor sampling progress periodically. When target sample collection time has been reached, close the canister valve. 4. Record the time and post-sampling pressure reading on the canister pressure valve. Do not let the vacuum be reduced to zero pressure as this will compromise the analytic results. 5. Remove the canister from the sample train and replace the brass cap. 6. Follow the leak check procedures described in Section 2.8. 7. Label the canister and its corresponding field data sheet with the sample number. 8. Fill out the rest of the field data sheet and chain of custody and document all information in a field logbook. 9. Ship samples to the laboratory for analysis. Summa samples do not need to be chilled after collection or during transportation. 2.6 SAMPLE COLLECTION USING SORBENT TUBES Sorbent tubes are provided by the laboratory, and selection of the sorbent tube media is dependent on the compounds to be reported. The pump should be calibrated before sample collection begins, and flow rates should be recorded. To collect soil gas samples using this method, the following procedure is used: 1. Connect the sampling inlet end of the sorbent tube to the soil gas probe with a union fitting. 2. Connect the other end of the sorbent tube to the pump using Tygon® or equivalent tubing. 3. Start the pump and record the start time. After the desired duration, stop the pump and record the end time. 4. Remove the sorbent tube from the probe and pump, and replace the end plugs on both ends of the tube. 5. Follow the leak check procedures described in Section 2.8. 6. Record the sample number,tube number, sample flow rate, collection date and time on the field data sheet and chain of custody and document all information in a field logbook. 7. Due to the sampling medium, samples must be stored and transported in a cooler with ice