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R10/71-51-1C between drilling locations The 11 soil borings were advanced to depths ranging between 5 feet to 94 feet Table 3 (see Appendix C) summarizes the soil boring (SB15, S1317, SB18, SB22, and SS23) specifications and Table 4 summarizes the monitoring well (MW13, MW14, MW16, MW19, MW20, and MW24) construction information Soil samples were obtained initially at approximately 1 5 feet below the surface and then at approximately five-foot intervals or change in lithology down to predetermined depths or groundwater encounter Where groundwater was encountered and a monitoring well was not to be installed in that boring, water samples were collected in order to get an idea of the potential groundwater contamination The laboratory results for these water samples will not be used for defining contamination plume nor will these be used as a quantitative measurement of contaminant levels The boreholes were then promptly backfilled with bentonite grout and cement All drill-samples were obtained using a modified California split-spoon sampler The appropriate number of stainless steel r sleeves and dummy brass sleeves depending on the inner diameter (either 2-inch or 2 5- inch) of the sampler were used The split-spoon sampler and sleeves were cleaned using a detergent solution and deionized water and inspected for complete decontamination 1 prior to use The soil samples were retained in sleeves placed inside the sampler Immediately following collection at each horizon, the stainless steel sleeve nearest the driving tip of the sampler were immediately covered with a Teflon sheet and capped at both ends The sieeves were then placed in resealable plastic bags and then placed into a cooler with ice for preservation of sample integrity The soil in the sleeves above the sleeves taken out for chemical sampling were emptied into resealable plastic bags and 1 were subsequently exposed under the sun and read the head space with a Foxboro Organic Vapor Analyzer Samplers were advanced eighteen inches by the repeated 30-inch drop of a 140-pound hammer Blow counts were recorded for each six inches of advance Refusal, caused by the encounter of sub-surface obstructions, was defined as failure to advance more ' than six inches for fifty blow-counts or the encounter of insurmountable boulders by the auger ' Soil logging and drilling activities were conducted under the supervision of Mr Ramesh Shah, a California-registered geologist Soil/Waste descriptions including information concerning the color, grain-size, grain-sorting, soil moisture and soil density as indicated ' by blow counts and any unusual features were entered in the field log book Soils were described with reference to the Unified Soil Classification System (USCS) (ASTM D2488- 84) The data were utilized to prepare soil boring logs presented in Appendix D r 13 r