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The first 4.7 million BCY of material will be hauled to the North, and will be placed at the toe of the landslide <br />• area. This should serve as a buttress against further movement of the slide block. Upon completion of the <br />buttress, spoils will be hauled to an off-site fill in Horse Gulch. For the safety of the miners working in the <br />Truck/Excavator pit, no material will be placed upslope of the operation. Backfilling of K Pit may occur in a <br />given block when that block is completed, and only if that block will remain downslope of any remaining <br />mining operation. <br />Block C may be started when the dragline has completed its pass along the Southern edge of Block B. <br />Block C will be mined in the same manner as described for Block B. Block B does not have to be complete <br />for operations to begin in Block B, provided truck and loader faces in Block B remain downslope of Block C. <br />For PR-6, the Horse Gulch fill is designed for 24.6 million BCY. When that fill is complete, Blocks B and <br />and a portion of block C should be fully mined. This allows backfilling to begin at the Northern edge of <br />Block B, progressing upslope. <br />The M12 series of maps in PR-6 depicts the planned Post Mining Topography. Sheet 3 specifically depicts <br />the K Pit area. The topography depicted meets the definition of approximate original contour, per Statute <br />34-33-103(3) and Regulation 1.04(13). The proposed topography closely resembles the general surface <br />configuration of the land prior to mining, and blends into and complements the drainage pattern of the <br />surrounding terrain. The variance of post mining elevations and pre-mining elevations are consistent with <br />Trapper's prior, and successful, reclamation efforts. As such, the Horse Gulch fill and K Pit Buttress qualify <br />as excess spoil, as defined by Regulation 1.04(45a). These fills will be left as permanent reclamation <br />features, consistent with the planned post mining land use of Rangeland and Wildlife Habitat <br />Both fills will be constructed with overburden, as defined by Regulation 1.04(83). Neither coal mine waste, <br />as defined by Regulation 1.04(22a), nor coal processing waste, as defined by Regulation 1.04(24), will be <br />used in the construction of either fill. Topsoil will be stripped and salvaged prior to construction, and no <br />organic material will be used in construction of either fill. <br />• The Horse Gulch area was chosen for excess spoil placement because the area contains neither <br />ephemeral streams, as defined in Regulation 1.04(42), nor intermittent streams, as defined by Regulation <br />1.04(69). This location will allow construction of a head of hollow fill, as defined by Regulation 1.04(56), <br />which will blend with the surrounding topography. Detailed cross sections can be found in PR-6, Appendix <br />T. <br />The K Pit Buttress location was selected with regard to geotechnical investigation which indicated its need <br />for stability both during and following mining operations. Detailed cross sections can be found in PR-6, <br />Appendix T. <br />The spoil and coal geochemistry of the K Pit is similar to the affected area, as defined by Regulation <br />1.04(7), of Trapper's current permit. In its mining history, Trapper Mine has not experienced problems with <br />acid or toxic forming materials, and does not foresee problems arising in the future. As previously stated, <br />no coal mine waste or coal processing waste will be used in the construction of either fill. <br />The hydrologic balance, as defined by Regulation 1.04(61), is protected with this mine plan. There is no <br />discernable change in the quality or quantity of water inflow to our outflow of the Yampa River Basin. <br />Upon completion of the K Pit, the general plan is to begin prestripping in L Pit. This will assist the dragline <br />operation, and provide for the continued backfill of K Pit. When K Pit is backfilled, spoil material removed <br />via T/S will be placed in the L pit spoils. <br />The final cut in any given pit may be open for as long as 18 months as the need to remove coal to allow for <br />continuous stripping operations is not a factor. Final cuts are a logical area to carry inventory. <br />is <br />3-39a <br />Revision: PQ-I- <br />Approved: <br />4'° 5c,