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R1 14 IN I 4.'Ida -1 S"o-1 L....... <br /> Ilcrman d FI:Iru,hl.v in.i >ttalton CA <br /> to the drilling. The PHYEj1ID and Reclamation District No. 2029 were notified 4 the fieldwork 48 <br />' hours in advance. <br />' 3.2 Drilling Procedures <br /> The monitor wells (MW-1, MW-2. MW-3 and MW-4) were drilled by Spectrum Exploration <br /> of Stockton. California (C57 license #512268). A Condor geologist was on site to supervise the <br /> drilling, soil sampling, and well installation. The monitor well locations are shown in Figure 2. <br />' Appendix A. Prior to commencement of fieldwork, a tailgate safety meeting was held and the site- <br /> specific Health and Safety Plan was discussed with, and presented to, all crew members for their <br /> signatures. <br /> The monitor well boreholes were drilled using 8-inch U.D., continuous-flight, hollow-stem <br /> augers. The augers were stearn cleaned before each borehole was drilled. The soil sampling <br /> equipment (i.e., split-spoon) was cleaned prior to collecting each sample. The cleaning procedures <br /> consisted of washing the sampling spoon in a solution of laboratory-grade, non-phosphate detergent <br /> and hydrocarbon-free water, and double-rinsing with hydrocarbon-free \\ater. <br /> The boreholes for MW-1, MW-2, MW-3, and MW--f were drilled to a depth of approximately <br /> 16, 13.5, 13.5, and 15 feet bgs, respectively. The static depth to groundwater was approximately 6, <br /> 4.5, and 4.5 ft bgs in MW-1, MW-2, and MW-3, respectively. MW-4 was dry at the time of drilling. <br /> fField observations during the drilling indicated that groundwater was present in the subsurface around <br /> MW-4 but was filling the borehole so slowly that the static depth to groundwater could not be <br /> determined. Because of the very shallow groundwater at the site, a soil sample was collected from <br /> each boring at what was expected to be the capillary fringe. Because of the very loose peaty soil, <br />' however, the soil sample collected from MW-3 at approximately 4 feet bgs was not retained by the <br /> sampler. <br /> 1 <br /> Samples were collected with a California-modified, split-spoon sampler fitted with three clean, <br /> brass liners. During the sampling, the split-spoon sampler was driven ahead of the auger. The <br /> uppermost liner was discarded. The middle sample liner was used for geological logging and for field <br /> screening using* an organic vapor analyzer (OVA) and the bottommost liner was prepared, as described <br />