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As noted on page 2.05-45.4, any required pressure-grout boreholes will be sealed at the time of construction. <br />Cement grout will be pumped through the boreholes to seal any wet zones encountered and the boreholes will be <br />• filled with grout and allowed to set-up on completion of grouting operations. Any surface casing extending above <br />ground surface would be cut-off flush with or below natural ground level. The MAC boreholes) will be plugged <br />and sealed using the same methods as previously described for the shaft seal. <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 pad; <br />and the shaft pad and access road disturbance areas will be regraded to reestablish effective drainage and blend with the <br />surrounding terrain. Cover over any cuttings remaining in the cuttings pit will be a minimum of 2 feet of suitable <br />material, and the postmining configuration will approximate the premining contours. As-built certification will be <br />provided to the CDMG following final closure, backfilling, and grading of the cuttings pit. Any excess road-base and <br />surfacing materials not required to reestablish approximate original contour will be hauled off-site and disposed of. <br />Stockpiled and windrowed topsoil will then be replaced on those disturbed areas where it was previously removed and <br />seeded with a pastureland seed mixture. <br />6-Main North Ventilation Shaft and Facilities (TR05-48, MR06-208, MR06-210, MR06-212, MRO~-224) <br />When the 6-Main North Ventilation Shaft and supporting equipment and boreholes are no longer required to support <br />ongoing or future mining operations, the associated surface facilities will be removed, the shaft will be plugged and <br />sealed, and surface disturbance areas will be reclaimed. The supporting equipment and any structural steel or tanks will <br />be removed and reused at another locale, salvaged, or disposed of off-site. Buried utilities will be stubbed-off below <br />grade and abandoned. Concrete pads will be broken up, and foundations will be demolished to at least 2 feet below <br />grade, and the resulting concrete debris will be disposed of in the shaft opening. The shaft collar concrete will also be <br />broken up and disposed of into the shaft opening, leaving an open space for the concrete slab and backfill materiaUshaft <br />cuttings to be placed in the shaft void. A cement plug will be placed in the bottom 15 feet of the shaft and the remainder <br />• of the shaft will be filled with inert material including the shaft cuttings and collar excavation materials. A cement plug <br />will be poured from ten feet below grade to within approximately 3 feet of the surface. The remaining 3 feet will be <br />filled with soil and graded to blend with the surrounding terrain. <br />As noted on page 2.05-45.5, any required pressure-grout boreholes will be sealed at the time of construction. <br />Cement grout will be pumped through the boreholes to seal any wet zones encountered and the boreholes will be <br />filled with.grout and allowed to set-up on completion of grouting operations. Any surface casing extending above <br />ground surface would be cut-off flush with or below natural ground level. Utility boreholes will be plugged, filled to <br />within 10 feet of the ground surface with inert material, and a cement plug will be poured from the top of the fill to <br />within approximately 3 feet of the surface. Any surface casing will be cut-off below grade, and the remaining hole <br />will be filled with soil material and graded to blend with the surrounding terrain. <br />Following removal of structures and equipment, and plugging and sealing of the shaft and boreholes, 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 pad; <br />and the shaft pad and access road disturbance areas will be regraded to reestablish effective drainage and blend with the <br />surrounding terrain. Cover over any cuttings remaining in the cuttings pit will be a minimum of 2 feet of suitable <br />material, and the postmining configuration will approximate the pre-mining contours. As-built certification will be <br />provided to the CDMG following fmal closure, backfilling, and grading of the cuttings pit. Any excess road-base and <br />surfacing materials not required to reestablish approximate original contour will be hauled off-site and disposed of. <br />Stockpiled and windrowed topsoil will then be replaced on those disturbed areas where it was previously removed and <br />seeded with a pastureland seed mixture. <br />U <br />MR08-229 2.05 - 106 08/01/08 <br />