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ventilation fan and associated equipment, emergency hoist equipment shaft heater, and electrical equipment will be <br /> removed and reused at another location, salvaged, or disposed of off-site. Concrete pads will be broken up and <br /> foundations will be demolished to at least 2 feet below grade, and the resulting concrete debris will be disposed of in <br /> the shaft opening. The upper 4 feet of the shaft collar and the concrete shaft slab will also be broken up and disposed of <br /> into the shaft opening. A cement plug will be placed in the bottom 15 feet of the shaft and the remainder of the shaft <br /> will be filled with inert material including the shaft cuttings and collar excavation materials. A cement plug will be <br /> poured from 10 feet below grade to within approximately 3 feet of the surface. The remaining 3 feet will be filled with <br /> soil, and graded to blend with the surrounding terrain. As noted in the discussion of construction for the 18-Left <br /> Ventilation Shafts, any required pressure—grout boreholes will be sealed at the time of construction. Cement grout <br /> will be pumped through the boreholes to seal any wet zones encountered and the boreholes will be filled with grout <br /> and allowed to set-up on completion of grouting operations. Any surface casing extending above ground surface <br /> would be cut-off flush with or below natural ground level. The MAC borehole and Utility Borehole will be <br /> Plugged and sealed using the same methods as previously described for the shaft seal. The pipeline will be <br /> reclaimed by cutting the ends of the pipeline off below the ground surface, capping the ends, and leaving the <br /> pipeline buried in-place. <br /> Following removal of structures and equipment, and plugging and sealing of the shaft and borehole(s); any cuttings <br /> remaining in the temporary mine waste disposal pit will be covered with excavated shaft collar material; road culverts <br /> will be removed and disposed of off-site; road-base and surfacing materials will be removed and placed on the shaft <br /> pad; and the shaft pad, substation area, sedimentation pond, and light-use road disturbance areas will be regraded to <br /> reestablish effective drainage and blend with the surrounding terrain. Cover over any cuttings remaining in the cuttings <br /> pit will be a mininunn of 2 feet of suitable material, and the postmining configuration will approximate the premining <br /> contours. As-built certification will be provided to the CDMG following final closure, backfilling, and grading of <br /> the cuttings pit. Any excess road-base and surfacing materials not required to reestablish approximate original contour <br /> will be hauled off-site and disposed of. Stockpiled topsoil will then be replaced on those disturbed areas where it was <br /> previously removed and seeded with a pastureland seed mixture. <br /> 13-Left Outby Utility Borehole (MR15-291) - The 13LT Outby Utility Borehole will have a limited life, being used <br /> only to support cementing operations in the final panel areas for the 12LT and 13LT Panels. When the borehole is no <br /> longer needed to support these activities,the borehole will be plugged and sealed,and surface disturbance areas will be <br /> reclaimed. A plug will be placed in the bottom of the borehole, cement grout will be pumped into the borehole to <br /> establish a bottom plug and to seal any wet zones encountered, the remaining borehole void will be filled with drill <br /> cuttings and/or suitable plugging materials to within five feet of the ground surface, a cement plug will be poured at <br /> the surface, and any surface casing extending above ground surface would be cut-off flush with or below natural <br /> ground level. Following plugging and sealing of the borehole, any mud pits will be allowed to dry-out and will be <br /> backfilled with the excavated material, road-base and surfacing materials will be removed and placed on the shaft pad; <br /> and the shaft pad and light-use road disturbance areas will be regraded to reestablish effective drainage and blend with <br /> the surrounding terrain. <br /> 9-East Utility Borehole Installation and Additional Boreholes (MR16-296, MR17-304) - The 9-East Utility <br /> Borehole installation is expected to be actively used for only about three years to support operations in the 9- and 10- <br /> East Wolf Creek longwall panels. When no longer needed, this installation will be reclaimed by plugging and sealing <br /> the boreholes, regrading the pad and road areas, reestablishing drainage, replacing soil materials, and revegetating the <br /> disturbed areas. A plug will be placed in the bottom of the boreholes, cement grout will be pumped into the <br /> boreholes to establish a bottom plug and to seal any wet zones encountered, the remaining borehole voids will be <br /> filled with drill cuttings and/or suitable plugging materials to within five feet of the ground surface, a cement plug <br /> will be poured at the surface, and any surface casing extending above ground surface will be cut-off flush with or <br /> below natural ground level. Following plugging and sealing of the borehole, any mud pits will be allowed to dry-out <br /> and will be backfilled with the excavated material,road-base and surfacing materials will be removed and placed on the <br /> shaft pad; and the shaft pad and light-use road disturbance areas will be regraded to reestablish effective drainage and <br /> blend with the surrounding terrain. Stockpiled soil materials will be replaced,and the reclaimed areas will be reseeded <br /> with the permanent rangeland seed mix,consistent with the prevailing land use at the time of disturbance. <br /> MR17-304 2.05— 106.1 01/12/17 <br />