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Description of the Reclamation Plan <br /> <br />Backfilling of Pits <br /> <br />Backfilling and grading is discussed in section 3.5 of the permit. After removal of all coal seams <br />which can economically be recovered, the pits at the Trapper Mine are backfilled with spoil <br />(overburden and interburden) and then graded by dragline and dozers. As a dragline removes <br />overburden and interburden, spoil ridges are created by dumping the material from a recently <br />opened pit into a recently mined-out pit. Dozers and graders then smooth the spoil ridges and <br />blend the ridges into the existing topography. <br /> <br />Timing of Backfilling and Grading <br /> <br />Timing of backfilling and grading is discussed in section 3.5.2 of the permit. In section 3.5.2, <br />Trapper indicates that most cuts will remain active longer than 180 days. This is due to the long <br />pit lengths, the need to remove interburden from above recoverable coal seams, and cycling <br />times. This is beyond the 180-day time limit for rough backfilling and grading in accordance <br />with Rule 4.14.1(1)(c). Trapper provided a detailed analysis that additional time is necessary in <br />accordance with this rule. However, Trapper commits there will be no more than three un- <br />regraded spoil rows, including the active spoil row, at any one time in each pit being worked. <br />This commitment meets the requirement of rule 4.14.1(1)(c). The Division proposes to approve <br />such a variance. <br /> <br />Topsoiling and Seeding <br /> <br />Permit sections 3.2 and 4.9 address topsoiling and section 3.6 addresses seeding. After final <br />grading of the spoil ridges, topsoil is placed on the spoil to a depth of 18 inches on cropland and <br />12 inches on rangeland. A variation of +/- 2 inches is allowed due to compaction and operational <br />considerations. Areas are then seeded with one of three main seed mixes, depending on the <br />elevation. Range site A&B seed mix corresponds to the highest elevations within the mine site; <br />range site C seed mix the lower elevations. Cropland seed mix occupies the lowest elevations. <br />The A&B range sites use the same seed mix which contains various grasses, forbs and shrubs, <br />while the range site C seed mix contains only grasses and forbs. Shrub clumps of approximately <br />1.6 acres are established from the transplanting of mature shrubs retrieved from the advancing <br />areas of the pits. Seeding will be done by both drill and broadcasting methods. Areas will be <br />drill seeded at a rate of no less than 30 lbs PLS per square foot or, if broadcast seeded, no less <br />than 45 lbs PLS per square foot. <br /> <br />Long-Term Ash Disposal Plan <br /> <br />Permit section 4.3.4 discusses ash disposal activities at the site. Trapper will continue to backfill <br />Ashmore Pit with ash from the Craig Power Plant. Ash will also be disposed in <br />Enfield/Derringer pit. Enfield /Derringer Pit is approved to remain idle until utility ash disposal <br />beings sometime after the 2013-2017 permit term. 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 /> <br /> <br />21 <br /> <br />Trapper MineJuly 9, 2013 <br /> <br />