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I <br /> After excavation, soil confirmation samples were collected from the four walls and bottom of the <br /> excavation. If a <br /> confirmation sidewall sample exceeded an RAO concentration, soil was <br /> h <br /> excavated 2 feet laterally beyond the confirmation sampling location, and the sidewall was <br /> exc Y Y <br /> j <br /> re-sampled. If the confirmation samples from the bottom of the excavation exceeded an RAO <br /> concentration, soil was excavated 1-foot deeper and 3-feet laterally beyond the confirmation <br /> sampling location, and the bottom soil was re-sampled. This process continued until all COC <br /> concentrations were below the RAOs. <br /> Treadwell & Rollo collected a total of 285 soil confirmation samples from the floor and <br /> sidewalls of the 37 RAP excavations. Figures 7 through 13 present the excavation dimensions <br /> and soil confirmation sample locations for the 37 RAP excavations. Sidewall soil confirmation <br /> samples were collected at approximately the same depth as the RI hot spot.sample locations. <br /> 3 The depths of sidewall samples ranged between 1 to 15 feet below ground surface (bgs). Soil <br /> s <br /> samples collected from the bottom of the excavation ranged in depth between 2 and 17 feet bgs. <br /> Each soil sample was collected by pushing a 2-inch-diameter by 6-inch-long stainless steel tube <br /> directly into soil from the excavation wall/floor or the excavator bucket. The ends of the sample <br /> tubes were covered with TeflonTM sheets; sealed with plastic caps, labeled,placed on ice in an <br /> insulated container and submitted for analyses under chain-of-custody protocol to Curtis & <br /> 1 <br /> Tompkins Laboratories in Berkeley, California a State-certified laboratory. <br /> The soil confirmation samples were analyzed for the COCs corresponding to each RAP <br /> excavation (Table 1). The RAP excavation confirmation sample analysis included: <br /> • TPHd and TPHmo using EPA Testing Method 8015 modified; <br /> • PAHs using EPA Testing Method 8270C; and <br /> J <br /> • arsenic and lead by EPA Testing Method 6010B. <br /> Tables 3 through 7 present the confirmation analytical results,.and Table 8 identifies the <br /> duplicate samples, and Table 9 presents the quality control/quality assurance sample results. <br /> The laboratory analytical reports are presented in Appendix B. <br /> 25971025.DGD 11 1 I August 2005 <br />