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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. The Horse Gulch fill is completed. The only portion of Trapper's operation located <br />downslope from the Horse Gulch Fill is Trapper's Horse Gulch 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 />there will never be more than four ungraded spoil rows (including the active one) at any one <br />time. <br />Topsoiling and Seeding <br />After final grading of the spoil ridges, topsoil is placed on the spoil to a depth of 18 inches on <br />cropland and 12 inches on rangeland. A variation of+/- 2 inches is allowed due to compaction <br />and operational considerations. Areas are then seeded with one of three main seed mixes, <br />depending on the elevation. Seed mixes contain various native grasses, forbs and shrubs, while <br />the lowest elevation site seed mix contains only grasses and forbs. Shrub clumps of <br />approximately 1.6 acres are also located throughout the reclaimed areas. Seeding occurs by both <br />drill and broadcasting methods. <br />Long -Term Ash Disposal Plan <br />The applicant continues to backfill Ashmore pit with ash from the Craig Power Plant. Ash will <br />also be disposed in Enfield/Derringer pit. The ash is approximately 60% fly ash, 20% bottom <br />ash, and 20% scrubber sludge. A maximum of 5,250 tons per day of the waste will be disposed <br />11 <br />