2008-05-28_REVISION - C1981019 (2)

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lands. The reclamation timetable for the various aspects of the mining operation are indicated in Section 2.03 on Table 1., Affected Areas For Mining and Reclamation. As indicated in Section 2.05.3, the east half of the coal lease will be mined from north to south. To meet the maximum coal recovery requirements of the U.S. Bureau of Land Management and to avoid disturbing the area twice, a strip of land 500 to 600 feet wide along the Streeter drainage will be left unreclaimed until the west half of the lease is mined (see Spoil Grading Map (Map 29)). The west half of the coal lease will be mined from north to south. The initial mining in section 15 and 16 will be "X" seam only. Mining will start on the east and west and progress toward the ridge in the middle of Section 16. Later, a portion of the west pit will progress into the northern portion of Section 16. The estimate of the cost of reclamation of the proposed operations required to be covered by the performance bond is found under Rule 3. As discussed in detail in Section 2.05.3, the mining method proposed by Colowyo is referred to as open-pit multiple seam/single seam dragline mining. The overburden material from the initial boxcut area was deposited in the Streeter Fill. As mining progresses to the south, overburden material from each successive cut will be backfilled into the previously mined out area. This cycle will be repeated for the entire mining area. Because an open-pit mining technique is employed, the regrading and backfilling of the spoil material will be as contemporaneous as possible behind the mined-out area to facilitate proper leveling of the overburden material. The mining techniques utilizing dragline and truck/shovel operation are shown in detail on Mining Range Diagram (Map 24), and show the approximate distance between topsoil removal and replacement. The backfilled mining areas will be graded to establish the approximate original contour and to blend in with the undisturbed areas outside the mining limits. Colowyo will grade all final slopes so that overall grades do not exceed 33%. Additional information on the backfilling and regrading plan are discussed further in Section 2.05.3 and Section 4.14. Where necessary, the spoil surface will be roughened by ripping or discing etc., to ensure a bond between the topsoil and spoil to reduce slippage. To date there is no evidence of topsoil slippage on reclaimed areas. A few small tension cracks resulting from settling of fill and topsoil have occurred in a few areas within a year or two after reclamation, but soon stabilize and begin to fill in. The final surface as shown on the Post-mining Topography Map (Map 19) will approximate the overall pre-mining grades. Appropriate cross sections that show the anticipated final surface configuration of the proposed permit area, in conjunction with the existing pre- mining topography, are shown on the Pre-mining and Post-mining Cross Section (Map 20). This final surface configuration also reflects an often neglected concept of providing topographic relief for wildlife habitat. The regrading plan reestablishes escape cover, south facing slopes for wintering big game populations and small drainages suitable as fixture location of stockponds necessary to achieve the post-mining land use. Colowyo has prepared this reclamation plan with the understanding that some aspects of current reclamation practices are still in the development stages. Therefore, a degree of flexibility has been provided to allow changes and modification as techniques are refined or 2.05-41 Revision Date: 3/14/08 Revision No.: TR-72