2008-10-07_PERMIT FILE - C1981047 (4)

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• Caterpillar 820 KW Generators (two) Euclid and Terex Front End Loaders Fairbanks-Morse Portable Truck Scale The Blue Ribbon Mine is an existing mine. Construction of all facilities is complete at this time. ~ (3) Mine Facilities Earthwork development began at the ,Blue, ~Ribbaw,-]yine..i.n mid-December of 1977. The mine facilities were operational by~'May of;;1478.:~:;;;F~9m~,,iu~e~~evelopment to refine and improve these facilities is an ongoing program. At the bench where entries to the mine were driven (elevation 6,470 feet), three parallel entries exist. The fan is Located in the northernmost entrance (#3). It pulls air through #1, which is used to provide access for men and materials. The • #2 entry is occupied by the coal conveyor. All three entries are supported with structural steel and lined with concrete. A haul road to the portal bench vas constructed from the Hubbard Creek Road, County Road No. 4405 Drive. The sub-base of the road was built by cutting into the hillside the required width and side casting the cut material over the slope to the vest. Along this haul road there is little or no road fill and therefore the requirements under 4.03.1(3)(d)(ia) are not applicable. The sub-base is, therefore, natural ground. A layer of coarse road gravel vas graded over the sub-base. Over the coarse gravel a layer of finer road gravel was graded. A typical cross-section is included to demonstrate this (Exhibit U, Page 2 and Page 2 enlargement). Refer also to the access road stability analysis included in Appeadia D. The applicant is aware that the road cut elopes found at the Blue Ribbon mine do not have a safety factor of more than 1.5 in colluvial soils, but the factors of safety are greater than 1.5 in rock. The thickness of colluvium found in these cuts is minimal and will not result in significant enviro~ental harm, for eliding is not expected with elope safety factors of greater than 1.1 (see Appendix D, a May 26, 103 (Rev. 6/15/82)