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Ramcon Standard Procedure <br /> HAWPDATAMMPROCEEDWHYPNCH <br /> Groundwater Grab Sample Collection With Hollow Stem Auger Equipment <br /> All drilling equipment that comes into contact with the ground (truck tires and pneumatic jacks <br /> excepted)or borehole is decontaminated prior to first and successive uses. The hollow-stem augers <br /> are advanced through the vadose zone and capillary fringe into water-bearing material. All <br /> procedures and precautions merited in hollow-stem auger drilling are incorporated. If the water table <br /> depth is known, from existing wells on site,the augers are advanced several feet past this depth. If <br /> specific depth discrete information is required,as may be the case for DNAPLS or metals,the target <br /> depth is reached. For most fuel hydrocarbons,the zone of interest is immediately below water table. <br /> The drill rod and end plug are removed from the boring; the augers are left in place in the boring. <br /> The decontaminated well point, well screen and hydropunch drive apparatus are assembled at the <br /> surface. The well point and sampler are attached to the end of the drill rod. The assembly is <br /> emplaced back into the hole. When bottom is tagged by the assembly, the depth is checked and <br /> compared with that of the augers in the ground. The depth should be consistent. The drill rod is <br /> marked at the surface, usually with chalk, and the assembly is advance into fresh, undisturbed <br /> formation to a depth below the lead auger bit. The depth below the bit will depend on the variable <br /> length of commercially available samplers. Three to five feet is typical. The drill rod is raised a <br /> lesser length, opening the sampler below grade and exposing the well screen to formation and <br /> formation fluids. Water level may be checked in the boring and the sampler with a decontaminated <br /> water level indicator. A decontaminated or pre-cleaned bailer is used (with clean cord) to collect <br /> a water sampler from within the well point. The sample is brought to the surface and immediately <br /> decanted into appropriate sample vessels. The samples are then secured, handled, transported and <br /> relinquished according to Ramcon standard procedure #3, sample handling. When sufficient <br /> samples have been collected and any necessary data collected and logged,the boring is grouted shut <br /> in accordance with permit conditions. The well point is typically left in place and grouted shut. <br /> H:IWPDATAIMIKEIPROCFED18H}PNCH <br /> Page 2 of 2 <br />