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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. K pit is currently in the reclamation <br /> process. Mining of the N Pit is discussed above. Reclamation of the N Pit will be <br /> accomplished by backfilling from seam to seam from the bottom to the top of the coal seam <br /> in the north and south highwalls as well as any endwalls. The backfilled pit will be graded to <br /> approximate pre mining contour and blended with surrounding topography. Final grading <br /> will take place along the contour where safety allows. Once the area is prepared for topsoil <br /> replacement,topsoil is placed on graded spoil and the seedbed prepared and seeded as <br /> described below. <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 had <br /> been planned to be disposed in Enfield/Derringer pit. However,with the early closing of the <br /> power plant this plan changed. <br /> The ash is approximately 60% fly ash, 20%bottom ash, and 20% scrubber sludge. A <br /> maximum of 5,250 tons per day of the waste will be disposed of at the Trapper Mine with an <br /> average of 1,222 tons per day expected. This is equivalent to an average annual volume of <br /> waste of about 231 acre-feet, after compaction. The applicant expects this waste burial process <br /> will continue for the life of the mine. Down-gradient ground water monitoring wells are in <br /> place to detect any potential degradation of the ground water due to leachate through the ash <br /> waste pile. <br /> Findings of the Colorado Division of Reclamation, Mining_ and Safety <br /> for Trapper Mine <br /> Explanation of Findings <br /> Pursuant to Rule 2.07.6(2) of the Regulations of the Colorado Mined Land Reclamation Board for <br /> Coal Mining, and the approved state program,the Division of Reclamation, Mining and Safety or the <br /> Board must make specific written findings prior to issuance of a permit,permit renewal or permit <br /> 12 <br />