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the problem the wells were overdrilled to the bentonite plug and neat-cement placed in the wellbore as reported in the drilling logs in Appendix IV The driller did not charge the client for time lost during this effort PHSEHD staff were onsite to observe the placement of the neat cement grout and verify that wells were completed as appropriate to PHSEHD requirements and as described in the approved workplan All drilling and sampling equipment was washed prior to use In addition,to minimize cross-contamination between borings, all appropriate downhole drilling and sampling equipment was washed between borings 3.3.3 Groundwater Grab Sample Collection Groundwater grab samples were collected from soil borings using a2-inch diameter disposable PVC weighted bailer Samples were collected from soil borings PT-SB-8,9,and 10(Figure 6) Groundwater sampled was from the first encountered groundwater at a depth of about 46 5 feet bgs The groundwater grab samples were labeled, packaged, stored on ice in an insulated chest for transport and transported under chain of custody manifest to Kiff Analytical laboratory in Davis, California 3.3.4 Monrtorine Well Installation and Development Completion of monitoring wells PT-MW4, 5, and 6 consisted of a 2-inch diameter PVC casing with flush points, installed down through the hollow stem augers in accordance with well installation protocol outlined I in Appendix Il Appendix IV contains detailed diagrams of the individual well completions The wells were constructed with 40 feet of 2-inch diameter solid PVC casing to a depth of 40 feet below ground surface A screened zone from 40 to 60 feet below ground surface was set with 2-inch diameter schedule 40 PVC casing Screen size was 0 010 inch The bottom of each well was completed with a cap Filter pack material consisting of Monterey#212 sand was placed between the screened PVC casing and the formation as the flite augers were removed A 24 inch thick bentonite seal was placed around the casing and the formation from a depth of 38 to 40 feet below ground surface Neat cement grout was placed around the casing and the formation from a depth of 37 to 2 feet bgs A metal traffic box that protected the wellhead was set to a depth of 15 feet below ground surface A locking well cap was placed on the wellbore that secures the top of the - wellborn A tabulation of monitoring well construction details is presented as Table 5 Mam1RlEncnronmentallPannarTexacolReporls15AR1203wpd Page 15