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1 0 <br /> i 1tadwell&Rolb <br /> 1� <br /> 4.2 Deviations from Workplan <br /> 1 Work was conducted in accordance with the 2004 Workplan with the following exceptions: <br /> • Approximately 715 cubic yards of soil was removed compared to 684 cubic yards as <br /> 1 estimated. <br /> 1 • Approximately 40,000 gallons of groundwater was pumped from the excavation_into <br /> Baker tanks for eventual treatment and discharge to the Sanitary Sewer. This is <br /> 1 approximately 10,000 gallons more than originally estimated in the 2004 Workplan. <br /> • Approximately 500 versus 4,500 pounds of ORCO was placed in the excavation prior to <br /> 1 backfilling. <br /> 1 4.3 Shoring and Soil Excavation <br /> On 24 April 2004 through 4 May 2004 the perimeter of the excavation was shored with metal <br /> sheet piles. The shored excavation dimensions were 30 feet long, 28 feet wide and 22 feet deep. <br /> 1 Approximately 715 cubic yards (cy) of soil were removed and stockpiled for characterization. <br /> Mr. Jeff Wong of the SJCEHD was periodically on-site to observe the excavation. Since the <br /> 1 excavation perimeter was shored, confirmation samples were not collected from the sidewalls. <br /> 1 4.4 Soil and Groundwater Sampling and Analyses <br /> Following five days of dewatering, on 11 May 2004, one soil confirmation sample was collected <br /> 1 from the bottom of the Area 16 excavation at 23 bgs (Figure 3). One groundwater sample was' <br /> also collected from the bottom of the excavation. Both samples were analyzed for TPHg and <br /> 1 BTEX compounds by EPA Methods 8015M and 8020 respectively. In soil confirmation sample <br /> 16-EXC-23, TPHg was detected at 7,200 mg/kg, and BTEX were detected at Z1 320nd <br /> 1 76prmQ/kg, respectively. In groundwater sample 16-EXC-W, TPHg was detected at 43,000 <br /> i µid BTEX compounds were detected at 820, 3,900, 309 and 7,000 gg/L, respectively._ <br /> 1� <br /> 1 25971021.DJS 6 18 November 2004 <br />