Laserfiche WebLink
r <br /> February 14, 1992 AA —���� <br /> ARCO Service Station No 2130, Stockton, California <br /> 1 <br /> During drilling, the geologist collected soil samples at approximately 5-foot intervals and <br /> classified the samples using visual and manual methods according to the Unified Soil <br /> Classification System (Plate C1, Appendix Q Descriptions of materials encountered are <br /> presented in the Logs of Borings (Plates C2 through C24) The materials consisted <br /> predominately of silt, clay, and silty sand <br /> The geologist used a PID to evaluate the soil samples for hydrocarbon vapors <br /> Hydrocarbons vapors were detected using the PID in soil from borings B2 through B8 below <br /> 30 feet below surface grade (bsg) <br />' Two to four soil samples from each boring were submitted to State-Certified laboratories <br /> for analyses The samples submitted for analyses are shown on the Chain Of Custody <br /> Records in Appendix B <br /> Installation of Wells <br /> We observed Woodward Drilling install four 4-inch-diameter vapor-extraction wells VW-1 <br /> through VW-4 in borings B3, B4, B5, and B7, respectively The vapor-extraction wells were <br /> installed to evaluate whether remediation of hydrocarbons in native soil underlying the site <br /> is feasible by vapor extraction Soil borings B2, B6, and B8 were converted to ground-water <br /> monitoring wells MW-1, MW-2, and MW-3, respectively, to evaluate ground water for <br /> dissolved hydrocarbons Details of well construction are shown on the Logs of Borings in <br /> Appendix C Well construction is summarized on Table 2 On December 31, 1991, our <br /> technician developed the wells <br /> • <br /> M3-4W 4 <br />