Laserfiche WebLink
n <br />u <br />11 <br />C� <br />F <br />r <br />L <br />L <br />C <br />L <br />L <br />11 <br />r <br />Ci <br />I' <br />0 <br />G <br />I <br />0 <br />Complete sampling with the following steps. <br />• Close the bag valve (valve stem pulled out and lock screw <br />tightened) and disconnect the bag inlet from the sampler <br />outlet. <br />• After removing the sample bag, activate the sampler pump <br />and obtain a final flow rate reading. Turn off the sam- <br />pler. <br />• Close the shutoff valve at the probe inlet. <br />• Transport the sample bag in its cardboard box to the labo- <br />ratory for analysis. Each sample must be analyzed within <br />72 hours. Take precautions necessary to preserve the <br />integrity of the sample. <br />• Record the sample information, as required, on the data <br />sheet. <br />Gas Migration Investigation <br />Probe Installation and Sampling <br />The probe borings will be 4 inches in diameter and drilled or hand- <br />augered to an appropriate depth (approximately 8 feet). The boring will <br />then be backfilled with 1/2 foot of 3/8 -inch or 1/4 -inch pea gravel. <br />The probe (see Figure 4) will be inserted and the boring will be back- <br />filled with pea gravel to a level of 2 feet above the probe foot. A <br />bentonite/soil mixture of 1:4 will be added to complete the backfill of <br />the hole; plain soil can be used if the clay content is moderately <br />high. To protect the probe, a plastic 10 -inch vault box will be placed <br />over the probe boring and soil mounded to approximately 3 inches above <br />the grade to promote drainage away from the probe. The probe casings <br />will be capped immediately after installation. A nipple will be placed <br />in the cap to allow samples to be taken without allowing air to <br />infiltrate the probe. <br />Each probe will be sampled no sooner than 24 hours after installation. <br />To test a probe, a technician will attach the Gastech meter to the <br />PJI 9390301 14 <br />