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Each successive pit cut occurs next to and parallel to the previous cut. When more than one seam <br />is recovered in a pit, partings are removed by dozer, or backhoe, or similar equipment if thin; or <br />by dragline, if thick. <br />The October 2006 landslide in the East Panel of Trapper Mine created a need for a change in <br />mining methods for the East Panel area, resulting in Permit Revision PR6. The K -Pit and L -Pit <br />(originally identified as G Pit) were originally planned as dragline pits, consistent with Trapper's <br />historical mining method. <br />Strip Pits <br />Trapper mined coal from the following four pits during the 2013-2017 permit term: <br />1. Ashmore East Pit <br />2. Kimber (K) Pit <br />3. L Pit <br />4. G Pit. <br />Pits advance generally southward. Individual cuts in pits are as much as 6,000 ft. long. The <br />maximum width of a cut is 200 feet. In 2002, D -Pit progressed to the point that it merged with <br />E -Pit. This combination D/E-Pit is approved for ash disposal. A (Ashmore) pit remains open for <br />ash disposal (see description of ash disposal below). <br />Removal of Topsoil and Overburden <br />Prior to disturbance, and in advance of pit construction, vegetation is cleared and topsoil is removed <br />and salvaged. Stockpiled soils are shaped and seeded to establish vegetation for protection from <br />wind and water erosion. After topsoil removal, the overburden is drilled and blasted in advance <br />of the pit. Overburden is then stripped by draglines, scrapers, truck/loader or bulldozers. Finally, <br />front-end loaders load coal into 90 -ton haul trucks, which deliver the raw coal to the Craig Power <br />Plant. <br />Trapper removed 24.6 billion cubic yards (BCY) of spoil material in the K -Pit and placed the <br />material in a permanent fill that is known as Horse Gulch Fill. Additional spoil from the K -Pit is <br />also placed north of the pit and elsewhere on the site to meet the requirements of the post -mine <br />topography. As of this permit renewal RN7, the Horse Gulch fill is completed. The only portion of <br />Trapper's operation located downslope from the Horse Gulch Fill is Trapper's Horse Gulch <br />sediment control pond. <br />Backfilling of Pits <br />After removing coal from economically recoverable coal seams, associated pits are backfilled with <br />spoil (overburden and interburden) and then graded by dragline and dozers. As a dragline <br />removes overburden and interburden, spoil ridges are created by dumping the material from a <br />recently open pit into a recently mined out pit. Dozers and graders then smooth the spoil ridges <br />and blend the ridges into the existing topography. <br />Timing of Backfilling and Grading <br />The Operator committed to the regulatory requirements of contemporaneous reclamation: that <br />Page 11 <br />Trapper RN7 Prepared by: R. Reilley <br />Nov 2017 <br />