2022-02-07_PERMIT FILE - M2022005

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EXHIBIT L Reclamation Costs In order to calculate maximum potential reclamation liability to the State, we have selected a point in time where reclamation costs could be at a maximum. It is assumed that the time of maximum mining disturbance will be midway through Phase I. During this scenario, no reclamation will have been performed on the active mining face, pit side slopes on both sides of the mining face, and about half the exposed pit bottom. Since backfilling side slopes and the active mining face to a minimum 3H:1 V slopes is more costly than "cut and fill" sloping, backfilling is used to estimate reclamation costs. Stockpiles with available topsoil/overburden for backfilling will be near the pit and areas for reclamation, so haul distances will generally be less than 1,000 feet. Each aspect is listed in the following table with associated disturbed area. Please refer to Exhibit D, Pre-Mining/Mining Plan, for a listing of disturbed areas that total 28.3 acres. This estimate will follow the same order as the listing in Exhibit D. Connell Resources Inc. is an earth moving and construction contractor and unit costs for reclamation activities were provided from bidding documents associated with similar projects. Since all structures used in the mining operation are portable, it is assumed that removal of the structures do not have associated costs. The active mining area will include the active mining face, un-reclaimed pit side slopes, un- reclaimed pit floor, and partially reclaimed pit side slopes and pit floor. The active mining face will be near vertical with a maximum length of 1,000 feet and an average height of 10 feet. In front of the active mining face, an area 100 feet wide will have been pre-stripped in anticipation of mining (2.3 acres). In addition, a maximum 500 feet of un-reclaimed pit side slopes may be adjacent to each end of the active mine face. These side slopes will also be near vertical with an average height of 10 feet. Framed by the active mining face and pit side slopes, the pit floor (11.5 acres) will be un- reclaimed, contain overburden, raw material, and product stockpiles. Following backfill, the areas are rough graded in preparation for topsoil/overburden growth medium placement, final grading, and seeding for revegetation. In addition to the active mining area,parts of the mine pit will be partially reclaimed. A maximum of 2,000 feet of pit side slopes dozed or backfilled to 3H:1 V, and an area of pit floor backfilled with a layer of topsoil/overburden growth medium, will require final reclamation. Since backfilling and grading may occur several seasons before final reclamation, the areas will be rough graded prior to additional reclamation activities. Final reclamation for these areas will include topsoil/overburden growth medium placement, final grading, and seeding for revegetation. Miscellaneous disturbed areas at the point of maximum disturbance will include the main site access road, internal haul roads, and other areas disturbed by mining activities. These areas will be tilled in preparation for topsoil/overburden growth medium placement, final grading, and seeding for revegetation. It is estimated that the combined area of these disturbances will be approximately two (2) acres. Since quality topsoil is scarce on the Carr Pit East site, vegetation growth medium will include the best quality topsoil/overburden material available. If available, a minimum of 6 inches of growth medium will be placed on all disturbed areas following backfilling, scarifying, and/or rough grading. Final grading of the topsoil/overburden growth medium will prepare the surface for seeding. After initial seeding and the first season's growth, it is estimated that approximately 20 percent of the seeded area will need to be re-seeded. Carr Pit East DBMS 112 Permit Application Page 26