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r-, <br /> KA10APAMAR <br /> Working To Restore Nature <br /> ±' 3.2 REMEDIAL ACTIONS <br /> 3.2.1 Soil <br /> Soil remedial actions consisted of source removal excavation conducted on October 7, 8, and <br /> Y`r 9, 1992. Approximately 375-400 cubic yards of soil were removed. The former diesel tank pit <br /> was opened to an approximate depth of 14 feet below grade (5-6 feet below groundwater) in <br /> order to remove contaminated soil previously found to exist above and below the water table. <br /> Excavation continued until photoionization detector readings and visual and olfactory evidence <br /> ~` indicated that no petroleum hydrocarbon contamination remained on the northern, eastern and <br /> P Y <br /> southern sides of the pit. To verify removal of the petroleum hydrocarbon impacted soils, <br /> confirmation samples were collected from the three "clean" sides of the excavation. The western <br /> wall of the former tank pit was excavated to the maintenance structure flooring edge. Samples <br /> := were collected from the western wall to determine the level and extent of contamination left in <br /> place. Depicted on Figure 2 is the extent of excavation and the locations of the soil samples <br /> collected from the sidewalls. The confirmation soil samples were analyzed for TPHd and <br /> BTEX. Sample analysis indicated that petroleum hydrocarbon impacted soils were totally <br /> removed from the northern, eastern and southern walls of the tank pit. Complete removal of <br /> -- petroleum hydrocarbon impacted soils from the west wall was not possible because impacted <br /> soils were beneath the maintenance shed and further excavation in this direction would have <br /> threatened the footings of the structure. Soil sample analytical results are summarized in Table <br /> 2. The pit was backfilled to grade with self compacting material and paved with asphalt. <br /> I-M <br /> On November 9, 1992 nine composite soil samples were collected from the excavation soil piles <br /> Fr: and analyzed for BTEX and TPHd. Excavated soil was stockpiled on site, underlain and <br /> f s <br /> covered by visqueen. The former location of the stockpiled soil, the estimated volume in each <br /> pile, and the soil pile sampling locations are depicted on Figure 2. Two soil samples were <br /> collected from each 50 cubic yards of soil, a total of nine samples, and composited by the <br /> r j <br /> 0W01951REF0RTSICL012594.FNL 5 <br /> t�fi <br />