2013-10-06_PERMIT FILE - C1981019

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RULE 2 PERMITS reclamation efforts and justifications for concepts such as variable topsoil depths, slope determinate vegetation community establishment and ethical management of the topsoil resource that apply to the Collom area as well. The pre- mining condition of the permit area has been characterized through collection of baseline data (Exhibit 10 Item 6). 2.05.4 (2)(a) Reclamation Timetable The sequence for reclamation following the mining process is shown on Map 29B (Spoil Grading — Collom). Final reclamation of the Little Collom X and Collom Lite pits will continue through 2033. A large, temporary out of pit stockpile of approximately 250 million cubic yards will be needed during the initial years of mining. As activities progress, a sufficient volume of backfill void will be created, and the Collom Lite pit should reach a steady state of operation where the advancing overburden face moves southward at the same rate as the advancing backfilling benches. This should occur approximately five years after mining is initiated. At that time, spoil regrading and subsequent reclamation activities will accelerate. The temporary out of pit stockpile is expected to remain in place until the final two years of mining activities. At that time, this material will be needed to fill the final pit void. 2.05.4 (2)(b) Reclamation Costs The estimate of the cost of reclamation of the proposed operations required to be covered by the performance bond will be found under Rule 3. Appropriate materials will be submitted for review during the technical adequacy phase of permitting. 2.05.4 (2)(c) Backfilling Plan As mining progresses to the south, overburden material from each successive cut will be backfilled into the previously mined out area and the additional spoil will continue to buildup in previously mined areas. Initially a temporary out of pit spoil pile will be created to the North of the Collom Lite Pit and will remain in place until the end of mine life. Table 2.05.6 -5 presents a mine wide volumetric calculation in support of post mining topography and illustrates that permanent out of pit spoil will not be needed. The backfilled mining areas will be graded to establish a stable post mine topography that blends into the undisturbed areas outside the mining limits (Map 19C). Colowyo will grade all final slopes so that overall grades do not exceed 3H:1 V (Map 20C). 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 in the existing permit area. 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 19C) will approximate the overall pre- mining grades (Map 19D). 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 20C). The regrading plan reestablishes escape cover, south facing slopes for wintering big game populations and small drainages suitable as future location of stockponds necessary to achieve the post- mining land use. 2.05.4 (2)(d) Topsoil Savage Collom — Rule 2, Page 105 Revision Date: 9/28/11 Revision No.: PR -03