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The sampling procedure requires one end of the tubing to be been inserted into the ground a bentonite seal must be
<br /> slipped over the sampling port and the other end over the formed between ambient air and the sample air. The
<br /> canister nozzle or flow meter (if required) to acquire an air- bentonite must be hydrated and create an air tight seal
<br /> tight connection . The valve should be opened at this time around the probe . If required IPA can be placed on the joints
<br /> and the initial pressure should then be recorded to verify that of the vapor probe and analyzed for in the sample to ensure
<br /> the Summa canister is under vacuum . The Summa canister that ambient air is not diluting the soil vapor survey samples .
<br /> is allowed to collect the soil vapor sample at a
<br /> predetermined duration . After the sample has been Once the sample apparatus has been set up new tubing will
<br /> collected record the final vacuum reading (approximately five be connected to the inlet of the SKC sample pump . The
<br /> pounds per square inch (psig)) to ensure that the flow meter pump operates at a low flow purge rate of 200 milliliters per
<br /> was working properly, if applicable. Immediately following minute to prevent air stripping of contaminants from the soil ,
<br /> the sample collection , complete sampling information is Once three volumes have been evacuated (minimum 4 .2
<br /> recorded on the label on the air sampling canister (e.g . , minutes of sample time) a sample can be collected .
<br /> sample ID , date , time, location , and temperature) . The Verification with a PID will determine when the maximum
<br /> sample is placed in a non-refrigerated , dry cooler with concentration is obtained and a sample should be collected ,
<br /> sufficient packing to ensure against damage during If measurable concentrations are not obtained with the PID
<br /> transport. Cooling samples will cause condensation of any after 7 purge volumes (10 minutes) a sample should be
<br /> moisture within the air sample, thereby distorting laboratory collected . Once a sample has been determined to be
<br /> analysis , collected new tubing will be placed on the effluent of the
<br /> sample pump running to the Tedlar bag , which should be
<br /> Summa canister samples are subject to hold times of filled to 3/4 of volume capacity. Caution should be taken not
<br /> typically 30 days and with some compounds a more rigid to overfill the sampling bag . The sample is placed in a non-
<br /> hold time of 14 days is required , refrigerated dry cooler with sufficient packing to eliminate
<br /> damage during transport. Cooling samples will cause
<br /> SOP43 condensation of moisture within the sample , thereby
<br /> SOIL VAPOR SAMPLING : SYRINGE SAMPLING distorting laboratory analysis .
<br /> TECHNIQUE
<br /> To minimize the potential for cross-contamination between
<br /> Prior to vapor sampling , the vacuum system must reach a air samples new polyethylene tubing will be used for every
<br /> stabilized air flow (cubic feet per minute) for approximately sample .
<br /> 15 minutes . Prior to the actual collection of the vapor
<br /> sample, the following data is recorded : air flow, temperature, Vapor samples are also subject to the same hold times and
<br /> and pressure at collection ports and gauges , must be stored as stated in SOP-10.
<br /> The sampling equipment consists of a clean , 100cc, gas- SOP-15
<br /> tight syringe and silicone septa. SOIL GAS SAMPLING FROM DIRECT PUSH SOIL
<br /> The sampling ports are brass connections , fitted with silicone BORING : "TEDLAR" BAG SAMPLING TECHNIQUE
<br /> septa , and threaded into a tapped hole in the system piping . To obtain soil gas samples from a direct push drill rig ,
<br /> Samples are collected by inserting a clean syringe into the advance a discreet sampling rod with a 6-inch retractable
<br /> septum and the plunger actuated several times . Each vapor screen to the desired sample depth. Release the
<br /> syringe should be purged of three syringe volumes before sample screen cover from the screen and retract the rod 6-
<br /> collecting the sample. On the fourth purge , the plunger is inches . Place a dry bentonite powder layer in the annulus to
<br /> extracted slowly until the syringe is filled with a gas sample , seal the borehole from surface air interference . Tamp the
<br /> then the syringe is withdrawn and the needle immediately bentonite powder, place a hydrated bentonite layer in the
<br /> plugged with a silicone stopper. The sample should be annulus , and follow with a second dry bentonite layer. Attach
<br /> placed in a non-refrigerated , dry cooler with sufficient the soil gas sampling diaphragm pump to the rod casing
<br /> packing to eliminate breakage during transport. Cooling using polyethylene tubing ,
<br /> samples will cause condensation of moisture , thereby
<br /> distorting laboratory analysis . The sampling equipment consists of a TedlarT74 bag
<br /> (available in 1 , 3 , 5, and 10 liter sizes) , a diaphragm pump,
<br /> Duplicate air samples should be collected as in SOP- 10 . and 3/16-inch-diameter polyethylene tubing (approximately 1
<br /> Vapor samples are also subject to the same hold times and foot long) . The TedlarTM bag should be fitted with an integral
<br /> must be stored as stated in SOP- 10. valve for filling and sealing the bag after sampling . The
<br /> diaphragm pump inlet and outlet are fitted with 3/16-inch
<br /> SOP44 hose barbs for attaching the sample tubing . A sample label
<br /> SOIL VAPOR SURVEY SAMPLING : "TEDLAR" BAG with the sample number and date and time of sample
<br /> SAMPLING TECHNIQUE collection is prepared and placed on the TediarTm bag .
<br /> The sampling equipment consists of a "Tediar" bag The sampling procedure requires one end of the tubing be
<br /> (available in 1 , 39 5, and 10 liter sizes) , an SKC universal slipped over the direct push drill rod sample port hose barb
<br /> sample pump , soil vapor probe , and 1 /4-inch4ameter and the other end over the diaphragm pump inlet hose barb
<br /> polyethylene tubing (approximately three feet long) . to form an air-tight connection. The sampling pump is then
<br /> started and the pump is purged for 1 minute with the vapor
<br /> A Roto-hammer or slam bar is used to obtain a three foot to be sampled . Following purging , the discharge of the
<br /> hole into the ground area, where the soil vapor sample will pump is then connected to the TedlarTm bag using a section
<br /> be collected . Once the hole has been formed the soil vapor of 3/164nch tubing . The pump is restarted and the bag is
<br /> probe will be inserted into the hole and advanced the opened and allowed to fill to approximately 3/4 of its
<br /> remaining two feet, five feet total below ground surface capacity. Caution should be taken not to overfill the
<br /> (bgs) , with the use of either a slide hammer, using a tee sampling bag . The sample is placed in a non-refrigerated
<br /> adapter and using physical force . Once the vapor probe has dry cooler with sufficient packing to prevent damage during
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