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5.1 SJC/EHD Rqport Review <br /> Pending the SJC/EHD review of the summary report four groundwater monitoring wells ill be <br /> installed at the approved/agreed locations on the Boy si e. a scuss the <br /> monitoring well drilling and installation procedures. <br /> 6.0 Field Methods—Drilling and Sampling Monitoring Well Exploratory Borings <br /> Four (4) exploratory borings will be drilled at approved PHS/EHD locations following review of <br /> the Limited Phase I Investigation report. Drilling and well installation permits will be secured <br /> from the SJC/EHD, and an underground utility clearance will be completed prior to doing the <br /> fieldwork. A site safety plan and traffic control plan will be prepared for the site work. <br /> The boreholes will be drilled with a truck-mounted hollow-stem auger rig. All drilling <br /> equipment and sampling tools will be cleaned prior to arriving, and before leaving the site. The <br /> decontamination process will use a tri-phosphate soap to wash the soil sampler between each <br /> sample run and each borehole. Augers and drill rods will be decontaminated in similar fashion <br /> between each borehole using a pressure washer as needed to remove soil/sediment adhering to <br /> the augers, rods and drill bits. The hollow-stem augers will be advanced and discrete soil samples <br /> will be collected at five-foot intervals of depth from each borehole. The augers and drill rod will <br /> be advanced to the desired sampling depth interval, and a drive split spoon sampler driven ahead <br /> of the drill bit The soil samples will be sealed with Teflon paper and plastic endcaps, labeled <br /> with a unique sample number, logged onto chain-of-custody forms and place in a chilled ice <br /> chest on crushed ice for transport to a State certified analytical laboratory. <br /> The borcholes will be logged using the Unified Soil Classification System under the supervision <br /> of a professional geologist. Additional lithologic information will be collected to describe the <br /> subsurface geology. The soil samples will be collected at five-foot intervals, at intervals of <br /> obvious contamination and at stratigraphic features of interest. Soil samples will be field <br /> screened with a portable photoionization detector(PID) for fuel hydrocarbons vapor and staining. <br /> Samples showing elevated PID readings will be selected for chemical analysis. If field screening <br /> is inconclusive, soil samples will be selected based upon possible staining, site stratigraphy and <br /> near the occurrence of groundwater. Upon completion of the borehole drilling and collection of <br /> soil samples, three (3) boreholes will be converted to groundwater monitoring wells using the <br /> procedures discussed below. <br /> Borehole drill cuttings, decontamination water, cement mixing and cleanup water will be placed <br /> into closed top drums, labeled and left at the Client specified location onsite. <br /> 7.0 Groundwater Monitoring Well Installation and Sampling <br /> 7.1 Monitoring Well Design and Installation <br /> -Three monitoring wells will be constructed using threaded Sch. 40 PVC casing; glues will not be <br /> used. Final well design will be modified to the site-specific conditions encountered in the <br /> borehole during drilling. Once the aquifer strata are defined, the casing will be lowered to the <br /> Page 4 of 6 <br />