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3.2 EXCAVATION PROCEDURES <br /> The excavation work will proceed in a southeast to northwest or northwest to southeast <br /> mode, excavating one discrete location and then proceeding to the next discrete location, <br /> with backfilling commencing in the same manner, once analytical results have been <br /> obtained. <br /> Since the excavation will be limited to a depth of 5 fbg, the excavation sidewalls will be <br /> dug neat (no slope) unless the designated excavation competent person determines <br /> sloping is necessary to maintain personnel safety. <br /> The top 6-to 8-inches of soil materials will be stripped off as clean topsoil and seed bank <br /> that will be placed over the final backfilled excavation areas. The stripped topsoil will <br /> be temporarily placed in a stockpile area in close proximity to the excavation area. <br /> Excavation will then commence at one end of the discrete location working parallel to <br /> the pipeline alignment. The remainder of the upper 3 to 4 feet of material would be <br /> excavated by the track excavator and transported by a wheeled loader to a separate <br /> potentially "clean' soil stockpile area located in close proximity to the active excavation <br /> area. This material is considered potentially "clean' given the depth of the former <br /> pipelines was approximately 4 fbg. The excavator would then proceed with excavating <br /> to the final depth of 5 fbg. <br /> CRA field personnel will screen soils, using a flame ionization detector (FID), for <br /> indications of crude oil impact throughout the vertical and lateral limits.Soil considered <br /> impacted,based on field indicators,will be segregated and stockpiled separately. <br /> Following excavation of impacted soils, any required sloping would be performed to <br /> permit access to the excavation by operated equipment. <br /> Completed open excavations will be surrounded with temporary orange construction <br /> safety fencing mounted to steel t-posts while waiting for analytical results. Once <br /> analytical results indicate no further excavation is warranted, the excavation will be <br /> backfilled. <br /> A street sweeper will be used for cleaning haul roads during excavation and backfilling <br /> activities. A water truck will be used to spray active work areas,stockpiles,haul routes, <br /> and excavation working areas to control dust. During periods of backfilling, a water <br /> truck will be used to ensure that the maintenance of the haul roads is managed. <br /> 060223(33) 8 CONESTOGA-ROVERS$ASSOCIATES <br />