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Ia <br /> E <br /> Field Practices and Procedures <br /> Page 5 <br /> f 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 Sampling <br /> A well known example of direct push technology 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 /> 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, water enters and 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 Plan. <br /> 1 <br /> ' I <br /> M:1Field PracticesWield P and P with CPT for Joes-revised 07-2004 by SJC.doc <br /> l <br /> _1 <br />