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1 <br /> i A <br /> G-R Field Methods and Procedures <br /> Grab Groundwater Sampling <br /> Grab samples of groundwater are collected from the boring using a parastaltic pump or micro-bailer. With <br /> the parastaltic pump, new Tygong tubing is placed in the pump prior to collection of each sample. The <br /> tubing is lowered into the boring through the GeoProbe equipment after groundwater has been allowed to <br /> collect. The parastaltic pump is used to evacuate water from the boring where it is discharged to laboratory- <br /> supplied containers appropriate for the anticipated analyses. With the micro-bailer, the cleaned bailer is <br /> lowered through the GeoProbe equipment into the groundwater. The bailer is allowed to fill, then is brought <br /> to the surface where the water is decanted into the sample container. The micro-bailer may also consist of <br /> a clean piece of tubing with a check valve at the bottom. The tubing is pumped up and down to bring the <br /> water sample to the surface and discharge the sample to the appropriate container. <br /> Following collection of the groundwater sample, the sample bottles are then labeled and placed in chilled <br /> storage for transport to the analytical laboratory. A chain-of-custody form is initiated in the field and <br /> accompanies the groundwater samples to the analytical laboratory. <br /> Soil Vapor Sampling <br /> Soil vapor samples are collected by advancing the GeoprobeQD to a discrete depth. Once the desired depth <br /> is attained, a 1 /4-inch polyethylene tubing is threaded through the inside diameter of the drive rods and <br /> connected either to a tedlar bag or summa canister. The bottom portion of the drive rod is retracted and a <br /> vacuum is induced to purge a soil vapor sample. Used tubing is discarded after each sample. <br /> A-2 <br />