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drainages. This is the same area as the Ashmore Pit. The L, M and Q seams will be mined as a <br /> strikeline pit using truck and loader stripping, dozer and dragline stripping in the reopend N Pit. <br /> Stripping in the N Pit occurred in 2018 and 2019 as per TR 119. A temporary out of pit spoil <br /> placement area was permitted with the N pit as a result of Technical Revision TR124. The pile is <br /> designed for 7.6 million loose cubic yards although less volume than that will be stored. The <br /> projected life of the spoil pile ranges from 4-6 years. Spoil pile design stability exceeded the <br /> requirements of the coal rules and were verified by engineering assessment. The spoil <br /> placement area will be reclaimed as contemporaneous reclamation allows for replacing the spoil in <br /> the pit as per the Trapper permit. Highwall mining may take place in the N Pit from the pit boxcut. <br /> The pit, developed in sections from west to east and contemporaneous backfilling minimizing the <br /> out of pit spoil placement. The use of Mining Technologies HW h800 Addcar System or a similar <br /> system employing a belt conveyor is planned. Utilizing a video system complete with continuous <br /> three dimensional location information provides the ability to sense roof and floor rock and thereby <br /> maintaining the miner within the coal seam. For an in depth description of Trappers highwall <br /> mining process please see section 3.1.4.2 of the permit document. <br /> Strip Pits <br /> Trapper mined or plans to mine coal from the following four pits during the 2018-2022 permit <br /> term: <br /> 1. Lancaster(L), Pit <br /> 2. Nighthawk(N)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, Derringer, D Pit progressed to the point that it <br /> merged with E-Pit. This combination D/E-Pit is approved for ash disposal. However TMI plans <br /> to reclaim this pit as there is no longer a need to utilize the D and E Pits for ash disposal. Ashmore, <br /> A pit remains open for ash disposal (see description of ash disposal below). <br /> With this permitting revision TMI requested a variance from approximate original contour for the L <br /> and Ash Pits. Mining will cease earlier than originally planned and the nearby Craig power station <br /> will reduce operation sooner than originally planned. Trapper is permitted to receive ash from the <br /> power station. The ash is disposed of and buried as permitted in the Ash Pit. <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 /> 11 <br />