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3.3.2 Topsoil Removal Suitable topsoil material from the entire 125-foot construction ROW will be removed in conjunction with clearing and grading and will be conserved in stockpiles within the ROW. Where topsoil and subsoil (trench spoil) conditions differ, they will be placed in sepazate piles (see Figure 2-1). To protect soils, construction activities will not be performed during periods when the soil is too wet to adequately support construction equipment. 333 Trenching Operations After the working area is prepazed, trenching operations will begin.. Trenches will be excavated with a backhce along most of the pipeline corridor. Under .some circumstances, awheel-ditcher may be used. The wheel-ditcher can excavate a trench width of approximately 28 inches, although width will vary with different types of ditchers or setups. Gentle topography and fine-textured soils might allow use of awheel-ditcher, while a backhce can be used in almost all soils. Trenches will be open for several days (the estimated maximum is 25 days) until the pipe is placed and backfilling is completed. This will allow enough time for ditching, stringing, bending, coating joints, lowering, and backfilling. ' , The depth of the trench will vary with the conditions encountered. The cover from the top of the pipe to ground level will generally be 36 inches, except in areas where significant rocks exist where this distance may be reduced to 30 inches. Rock that is placed back into the trench will be crushed to a maximum diameter of 5 inches. In some cases, the pipeline trench maybe 5 to 10 feet deep, e.g., where the proposed pipeline passes under existing pipelines, roads, or other obstacles. Ramps that can be negotiated by livestock or wildlife will be placed across the trench at intervals not to exceed 1 mile wherever the continuous pipeline trench is not interrupted by a road or pipeline crossing. The excavated trench will be inspected every morning for livestock or wildlife that may have fallen in during the night. Steep, rocky terrain has been identified at four locations: 1) at the upper end of Hatch Gulch, 2) immediately south of the second Piceance Creek crossing, 3) in Stewart Gulch at the northern end of Bames Ridge, and 4) at Davis Point. In rocky terrain, arock-trencher (also known as a rock-saw or arock-hammer) will be used to minimize environmental disturbance. Backhce hydraulic rams will assist in rock excavation where rock-trenchers are ineffective. No blasting is planned for excavation of these areas because of the close proximity of the • existing natural gas pipelines. A likely exception is the section off the east face of Pipelire Plan of Development 21 Yatilcee Gulch Sodium Minerals Project Hmerion Soda, LLP.