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. still were present beneath the open pit area. This sampling confirmed that residual diesel <br /> impacted soils were present beneath and adjacent to the pit. <br /> Kleinfelder was retained by Mr. Calkins to evaluate the site soils with respect to maintaining <br /> the structural integrity of the building and utilities near the existing excavation. The July 21, <br /> 1993 Kleinfelder report recommends that any further excavation in the pit area should <br /> maintain a 1 horizontal to i vertical slope from the base of the building. This cut slope <br /> allows the additional excavation in the vicinity of boring SB-3 behind the building to about <br /> 18 feet and in excess of 30 feet in the center of the excavation pit. A copy of the report is <br /> attached to this work plan. <br /> 3.0 WORK PLAN <br /> 3.1 Over Excavation of Soils <br /> Diesel impacted soils will be excavated from the pit and stockpiled on site. Initially the <br /> excavation will be controlled by the visual appearance of the soil and the maintenance of the <br /> 1:1 recommended cut slope to protect the integrity of the building and utilities. Obviously <br /> impacted soils will be excavated and stockpiled on visqueen or plastic to isolate the soils <br /> from the underlying oiled soils or asphalt paving. <br /> 3.2 Excavation Soil Sampling <br /> After the removal of visually impacted soils has been completed, two soil samples will be <br /> collected from the new pit bottom and one from each sidewall of the tank excavation, and <br /> analyzed for TPH as gasoline and diesel and BTEX to confirm that the excavation had been <br /> satisfactorily completed. Should impacted soils be below the 1:1 excavation cut slope, the <br /> analyses will document the diesel concentrations being left in place. Sample analysis results <br /> will be evaluated prior to any further pit excavation or backfilling of the excavation. <br /> Soil samples for laboratory analysis will be collected in brass liners. The liner will be <br /> pushed into the soil to minimize the loss of volatile compounds. Soil samples will be <br /> analyzed for TPH as diesel and gasoline and BTEX using methods modified 8015 and 8020, <br /> respectively. Evaluation of the analytical test results will determine whether additional soil <br /> excavation will be required. <br /> 3.3 Stockpile soil Sampling <br /> Soil samples will be collected from the stockpile and analyzed for TPH as gasoline and diesel <br /> and BTEX. Samples will be collected from a grid, which will be laid out on the newly <br /> graded soil pile. One sample will be collected from approximately each fifty (50) cubic <br /> yards of material. Samples will be collected using a modified California sampler or <br /> equivalent, using cleaned brass liners. The brass sleeve will be capped with teflon, sealed, <br /> 5003H 3 <br />