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ARCADIS Ms. Kathy Amaru October 19, 2010 for the presence of volatile organic compounds using a MiniRAE 2000 photo- ionization detector(PID). Soil around former borings SB-02 and SB-13 was excavated vertically to approximately seven feet bgs which is approximately one foot below the impacted soil observed during the April 2010 sampling. The first three vertical feet of the SB- 02/SB-13 excavation was removed with the air knife/vacuum truck due to the presence of subsurface utilities. The final four feet this excavation was conducted with the backhoe. The presence of above ground structures and subsurface pipelines and conduits limited the ability to remove additional soil horizontally in this area. Soil around former boring SB-04 was proposed to be excavated vertically to approximately 10 feet bgs which is approximately two feet below the impacted soil observed during the April 2010 sampling. Potentially affected-soils were observed at approximately seven feet bgs to 10 feet bgs. Soils were removed to eight feet bgs along the north side wall. Further vertical excavation along the north sidewall was terminated when the upper portion of this sidewall became unstable and began sloughing. A 10-inch subsurface water line is adjacent to the north sidewall at approximately four feet bgs and further soil removal could potentially undermine the stability of this utility. The east and south sidewalls were vertically excavated to approximately 11 feet bgs and the bottom was excavated to approximately 11.5 feet bgs. Groundwater was not encountered in either of the excavated areas. Removed soil was loaded into roll-off bins prior to disposal. Approximately 48 cubic yards(cy) of impacted soils were excavated from the two soil removal areas. The final limits of the excavation are shown on Figures 2 and 3. Confirmation Soil Sampling After accessible impacted soils had been removed to the extent feasible without jeopardizing nearby structures and underground utilities, confirmation soil samples were collected from the floor and sidewalls of the excavated areas. Post-excavation confirmation soil samples were collected from the bucket of the backhoe due to the depth of the excavations. One sidewall confirmation soil sample was collected from the approximate midpoint of each of the excavation sidewalls at depth intervals that correspond to areas exhibiting field indications of potential impacts. If potential impacts were not observed sidewall samples were collected at depths where previous samples indicated impacts were present. Page: 0 111012775 d. 4/12