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-56- <br /> worst case assumption of instantaneous application of the entire structure's <br /> five year configuration load. Utilizing this worst case assumption, the <br /> amended analysis projects a worst case static slope safety factor of 1 .6 and a <br /> corresponding worst case pseudo-static slope safety factor of 1 .35 for the <br /> proposed pile. The applicant has demonstrated, to the Division' s <br /> satisfaction, that the proposed coal processing waste pile's foundation will <br /> provide adequate support under realistic anticipated rates of loading. <br /> The proposed operation will be in compliance with the requirements of this <br /> section. <br /> XIX. Roads - Rules 2.05.3(3) and 4.03 <br /> Information on roads reviewed by the Division can be found in Section II-B of <br /> Volume 1 , Appendix II-B-7 of Volume 3, Chapters V and VI of Volume 7 of the <br /> application, and Permit Revision No. 1 . <br /> Approximately twelve miles of graveled haul roads connect the preparation <br /> plant with the five mines. In addition, there are several miles of light use <br /> roads in the areas around the mine portals and an access road approximately 4 <br /> miles long from Redstone to the preparation plant. <br /> The twelve miles of haul roads within Coal Basin are used mainly by 30 ton <br /> off-highway trucks to transport the run-of-mine coal from the mines to the <br /> preparation plant. The haul roads, which connect the preparation plant at <br /> 8,000 feet with the mines at approximately 10,000 feet elevation were <br /> constructed with grades ranging from 2% to 9%. The roads are 50-60 feet wide <br /> and have been constructed within 60 foot wide right-of-ways. Road cut <br /> embankments in unconsolidated material are not steeper than 1v:1 .5h and are <br /> not steeper than 1v:0.25h in rock. The applicant has not supplied evidence <br /> that embankment slopes meet the requirements of Rule 4.03.1 (3) (d) (ix) . <br /> However, some of these roads have been in existence since Mine No. 1 was <br /> opened in 1956 and all have been in existence since Mine No. 5 was opened in <br /> about 1971 . These embankments will be surveyed as part of an extensive haul <br /> road mapping system as discussed later in this section. <br /> Following completion of the rock tunnel project, there will be no need for the <br /> present 50-60 feet wide haul roads. The haul roads will be reclaimed by <br /> reducing the present width to 20-30 feet. This size reduction will occur by <br /> moving the drainage ditch into the center of the road and allowing the cut <br /> slope to slough. This would reduce the haul roads to an access road status. <br /> These access roads will remain as part of the post-mining land use. The U.S. <br /> Forest Service has requested that these roads be retained, as evidenced by the <br /> letter in Appendix V-C-1 of Volume 7. <br /> The Division expressed concern that more detailed plans for reclamation of <br /> this complex road system would be necessary. Haul roads should be mapped and <br /> categorized in accordance with their geology, exposure to avalanches and <br /> landsliding, type of construction (cut versus fill) , original cross-slope <br /> angles, etc. Each typical category of haul road should then be analyzed in <br /> order to determine what specific backfill , grading, drainage, and reclamation <br /> procedures would best assure stability of the final reclaimed configuration. <br /> Optimum procedures should then be proposed as the reclamation plan for each of <br /> the typical categories of haul road. <br />