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Description of the Reclamation Plan <br />Backfillin og_ f Pits <br />After removal of all coal seams which can economically be recovered, the pits are backfilled with <br />spoils (overburden and interburden) and then graded by the dragline and dozers. As a dragline <br />removes overburden and interburden, spoil ridges are created by dumping the material from the <br />pit opened into the mined out pit. Dozers and graders then smooth the spoil ridges and blend the <br />ridges into the existing topography. Due to the nature of the overburden and interburden after <br />being blasted and removed from the pit, the material occupies approximately 25% more volume <br />than in its original condition. When replaced and regraded, the result will be such that the <br />topography of the reclaimed surface will be slightly higher than the original surface (an average <br />of 12 feet). <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. The operator has committed to the criteria that there will never be <br />more than four un-graded spoil rows (including the active one) at any one time. This has been <br />approved as a variance by the Division and is 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 PLS per square foot or, if broadcast seeded, <br />no less than 45 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 />Trapper Mine 15 July 25, 2008