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Drilling will be terminated when groundwater is reached (estimated <br /> to be between 50 and 60 feet) or when field screening suggests that <br /> the vertical limit of contamination has been reached, whichever is <br /> shallower. <br /> The lateral extent of contamination will be determined by "stepping <br /> out" from CM-1 and drilling additional borings . The estimated depth <br /> of these borings is between 30 and 50 feet, but will depend on soil <br /> conditions and evidence of contamination. Depending on the results <br /> obtained from CM-1, one boring may be terminated within the <br /> capillary fringe and a hydropunch sampler used to punch into the <br /> saturated zone and collect a groundwater sample. <br /> At present, we estimate that 20 samples will be selected and <br /> transmitted to McCampbell Analytical Laboratories in Pacheco, <br /> California for analysis . One or more samples will be analyzed for <br /> total lead. <br /> Upon completion of all field and laboratory �ork, a Preliminary <br /> Investigation and Evaluation Report will be prepared by a <br /> California registered geologist. The report, will be used to <br /> determine whether soil and/or groundwater remediation is required. <br /> 4 .0 PROCEDURES <br /> 1 ) Notify San Joaquin EHD at least 48 hours prior to field work. <br /> 2 ) Drill five vertical borings to depths of 30 to 60 feet below <br /> grade using a hollow-stem auger drilling rig. <br /> 3) Collect discrete soil samples at 5-foot intervals, using a <br /> California modified split-spoon sampler loaded with three 6" <br /> brass sample sleeves . <br /> 4) Preserve the bottom sleeve by covering theends with aluminum <br /> foil or teflon sheets, capping, and sealing with duct tape. <br /> Place samples in a cooled ice chest. <br /> 5 ) Screen the middle sample for the presence of organic vapors <br /> using a portable photo-ionization detector (PID) and record <br /> the measurement on the boring log. <br /> 6) Extrude the middle and upper sleeves and record the sample <br /> descriptions on the boring log in accordance with the Unified <br /> Soil Classification System. <br /> 7 ) Decontaminate the sampling equipment between samples . <br /> 8 ) Steam clean the drilling equipment between borings . <br /> 9 ) Place auger returns on visquine. <br /> 10) Use a hydropunch sampling device to collect a groundwater <br />