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1 a excavation and Building 817 (Appendix A, Photo 5). Approximately 45 cubic yards of stockpiled soil was covered with visqueen after completion of the field activities on April 20, 1992 (Appendix A, Photo 6). Asphalt pavement was stockpiled in a separate pile to the south of the excavated soil to the west of the excavation. The associated piping that was removed from the tank excavation was placed with the excavated soil. All piping that was not removed was capped at the sides of the excavation. Currently, an eight -foot high chain link fence surrounds the stockpiled soil, asphalt, and associated piping that were removed from the tank excavation (Appendix A, Photo 9). After removal of the tank and associated piping, the following materials were observed in a cross section of the tank excavation pit sidewall. The uppermost 14 inches of material consisted of Iasphalt underlain by aggregate base course. Below the base course, to a depth of approximately D seven feet, fill materials were horizontally variable. The eastern on -third of the sidewall consisted of medium sand, gravel, and cobbles to four inches in diameter. The central portion of the sidewall consisted of well graded fill sand and the western portion of the sidewall consisted mainly of sandy clay with some well graded fill sand. The excavation pit was terminated at seven feet because of the presence of a concrete slab. Approximately 25 dime -sized (15 millimeter diameter) holes were observed along the bottom of the tank at the time of its removal. A significant amount of rust was observed on all exterior areas of the tank. The soil in the excavation pit showed signs of historic leakage from the tank and associated piping around the tank, including soil staining and PID readings exceeding 500 ppm. A total of three soil samples were collected during tank removal activities. Two soil samples were collected from the excavation sidewalls, one from each end of the UST; and one sample was collected from under the product supply piping. Soil samples were collected by PRC personnel at the locations shown on Figure 3. The two soil samples from the UST excavation pit were collected on April 20, 1992. This was accomplished by driving a 2 -inch (inside diameter) by 6 -inch long brass liner into soil removed from the excavation pit by backhoe bucket. Sample NCS -3 was collected at a depth of 6 feet at the west end of the excavation and NCS -4 was collected at a depth of 7 feet at the east end. Soil sample NCS -5 was collected on April 24, 1992, from a depth of 5.5 feet below ground surface (bgs) in the product delivery piping trench. The sample was collected by removing 6 inches of soil from the bottom of the trench and then driving a 2 -inch (inside diameter) by 6 -inch long brass 7