2008-02-22_APPLICATION CORRESPONDENCE - C2008086 (46)

Home Browse Search

CHAPTERTWO Alternatives The proposed rail alignment was modified to mitigate safety and environmental concerns. The following changes have been made to the proposed alignment: • A loop track near the loading facility at the mine site was designed. • In response to safety concerns, the alignment was modified to construct agrade-separated crossing at the intersection of the proposed rail alignment and SH 139. • The proposed alignment was modified to minimize impacts to wetland areas. • Grades were adjusted to comply with UPRR standards. • The proposed alignment was modified to balance the earthwork for construction. Figure 2-1, Rail Alignment Revisions and CR 10 Realignment, depicts these various modifications. Cuts and Fills To construct the rail alignment, cuts and fills would be necessary to provide a level, gently sloping railbed. Railroad standards permit no more than a 2-percent grade. Maximum curve radius will not exceed 10 degrees (573 feet), with 6 degrees (955 feet) preferred. The railbed width would be approximately 24 feet. Fill slopes would be 2 (horizontal) to 1 (vertical) (2H:1 V) unless conditions warrant flatter slopes. Cut slopes would be not less than 1. SH:1 V in common material, with steeper slopes allowable in rock cuts. See Figure 2-9, Typical Cut & Fill Sections, for depictions of typical sections. Cuts and fills vary, with 25- to 50-foot-deep cuts and fills being common. The deepest cuts and fills are located in the loadout area, where 90-foot- deep cuts are projected. Utilities such as gas lines in the cut and fill areas would be relocated, cased, or both. CAM owns or has easements across the private lands along the applicant-proposed alignment, so there would be little need to relocate or case irrigation pipelines or relocate overhead power lines on private properties. Culverts would be installed under the railbed at the location of each significant ephemeral channel; and bridges or concrete boxes would be constructed at major drainages and the SH 139 underpass. Construction Information A sequential construction process would provide for cut and fill, compaction, and track laying along the railroad corridor. Earth moving for the railbed would be performed with a fleet of articulated six-wheel-drive dump trucks that would be loaded with a large, tracked backhoe or front-end wheel loader. Two push-pull scrapers would likely assist the earth-moving operation. The push-pull scrapers may be the best equipment for topsoil salvage. The equipment spreads shown in Table 2-3, Earth Moving, have the capacity to excavate, place, and compact approximately 20,000 cubic yards per day. There are approximately 2,400,000 cubic yards to move. While the cuts and fills would be balanced, some topsoil would need to be stored along the railroad. Therefore, the equipment spreads would be on site approximately 120 work days, or 6 months, assuming two 10-hour shifts per day; five days per week. The anticipated earth- moving spread is shown on Table 2-3. 2-34