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Description of the Reclamation Plan <br />Backfillin, of Pits <br />After removal of all coal seams which can economically be recovered, the pits at the Trapper <br />Mine are backfilled with spoil (overburden and interburden) and then graded by dragline and <br />dozers. As a dragline removes overburden and interburden, spoil ridges are created by dumping <br />the material from a recently open pit into a recently mined -out pit. Dozers and graders then <br />smooth the spoil ridges and blend the ridges into the existing topography. <br />Timing of Backfilling and Grading <br />Backfilling and grading will not be contemporaneous within the time limits of the Rules and <br />Regulations, due to the long pit lengths, the need to remove interburden from above recoverable <br />coal seams, and cycling times. While the Operator has committed to the regulatory requirements <br />that there will never be more than four un- graded spoil rows (including the active one) at any one <br />time, the operator is seeking a variance from the requirement that rough backfilling and grading <br />is completed within 180 days following coal removal. The Division proposes to approve such a <br />variance. The operations will be bonded accordingly. <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. Range site A &B seed mix corresponds to the highest elevations <br />within the mine site; range site C seed mix the lower elevations. Cropland occupies the lowest <br />elevations. The A and B range sites use the same seed mix which contains various grasses, forbs <br />and shrubs, while the range site C seed mix contains only grasses and forbs. Shrub clumps of <br />approximately 1.6 acres are established from the transplanting of mature shrubs retrieved from <br />the advancing areas of the pits. Seeding will be done by both drill and broadcasting methods. <br />Areas will be drill seeded at a rate of no less than 30 lbs PLS per square foot or, if broadcast <br />seeded, no less than 45 lbs PLS per square foot. <br />Long -Term Ash Disposal Plan <br />The applicant will continue to backfill Ashmore pit with ash from the Craig Power Plant. Ash <br />will also be disposed in Enfield/Derringer pit. The ash is approximately 60% fly ash, 20% <br />bottom ash, and 20% scrubber sludge. A maximum of 5,250 tons per day of the waste will be <br />disposed of at the Trapper Mine with an average of 1,222 tons per day expected. This is <br />equivalent to an average annual volume of waste of about 231 acre -feet, after compaction. The <br />applicant expects this waste burial process will continue for the life of the mine. The permit <br />prohibits ash disposal in the down dip end of a pit where a spoil aquifer may develop. The ash <br />must be covered with at least 10 feet of non -toxic spoil prior to final reclamation. Although <br />column leaching tests predict that no ash leachate will form, down - gradient ground water <br />monitoring wells are in place to detect any potential degradation of the ground water. <br />Trapper Mine 17 July 9, 2013 <br />