2013-06-12_PERMIT FILE - C1994082 (5)

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highwall slopes would be reduced to 3H: 1V. This produces a final stable topography that could not only be revegetated, but would also allow drainage to flow through the pit area without impounding water. However, in reality, this is not achievable; instead most slopes are constructed between 5H:1 V and 3H:1 V. It was also assumed that in most cases there would be four standing spoils behind the open pit. This is a very conservative estimate because, in most cases, reclamation grading is current to within two spoil piles. However, in the Neck Pit area there was only one spoil ridge constructed. The cut and fill volumes are balanced to determine material needed to create the above - described topography. A swell factor of 17 percent was utilized for the bonding estimate. The adjacent spoil would be dozed into the open pit and the three other spoils would be graded into the adjacent v's created by the spoil (see appropriate worksheets in Attachment 25 -1). Highwalls will be reduced and sloped towards the open pit. This would be accomplished by drilling and shooting the highwall and then dozing the blasted material into the open pit. See appropriate worksheets in Attachment 25 -1 for a complete listing of volumes to be dozed into the open pit. Various computer programs are used to determine equipment production. See appropriate worksheets in Attachment 25 -1 for production and costs. The 2004 topography (determined from aerial photography) and postmining topography maps were compared for material movement. Although a specific postmine topography map is not available for a 2004 mine closure, drainage patterns will generally remain the same as the planned final topography. Ripping Work This task includes dozer work in final pit and haul road areas that need to be ripped to alleviate compaction following regarding. Road Reclamation This task consists of dozer and motorgrader work to narrow and blend temporary and permanent roads into the surrounding topography and to place the excess material in appropriate locations. Originally, it was assumed that surface material/gravel ripped to narrow roads and parking areas would be hauled to a final pit for disposal. However, the sequencing and timing of the various phases of reclamation will have the final pit areas totally reclaimed before the roads and parking lots are reclaimed. Therefore, the material will be ripped and dozed and configured in place. Finish/Final Grading This task represents final grading (versus rough grading) of backfilled pit areas. It includes such things as knocking down small piles and/or ridges of spoil that may have TR -53 3 Revised 05/13