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= 1 <br /> Field Practices and Procedures <br /> Page 5 <br /> 1 <br /> retracted from the hole. Continuous grouting will prevent:cross contamination of water <br /> bearing zones that can occur through an open borehole. The boring will be backfilled to <br /> surface grade. An asphalt patch will be placed,over the borehole.. <br /> Direct Push Technology, Water Water Samplin `} <br /> A well known example of direct push techryology for water sampling is the Hydropuncho. <br /> For the purpose of this field method the term hydropunch will be used instead of direct <br /> push technology for water sampling. <br /> r <br /> The hydropunch is typically used with a drill .rig. A,boring is drilled with hollow stem- <br /> augers to just above the sampling zone. In some soil conditions the drill rig can push <br /> directly from the surface to the sampling interval. The hydropunch is conveyed to the <br /> bottom of the boring using drill rods. Once on bottom the hydropunch is driven a <br /> maximum of five feet. The tool is then opened by lifting up-the drill rod no more than <br /> four feet. Once the tool is opened, watersentcrs an'd a sample can be'collected with a <br /> bailer or tubing utilizing a peristaltic pump. Soil particles larger than silt are prevented <br /> from entering the tool by a screen within the' tool. The water sample is collected, labeled, <br /> and handled according to the Quality Assurance Plana 1 <br /> i <br /> =k <br /> MAReld Practiccfficld P and P with CPT for Joes-revised 07-2004 by SJC.doe <br />