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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 <br />above ground surface would be cut-off flush with or below natural ground level. The MAC boreholes) will be <br />plugged 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 <br />culverts will be removed and disposed of off=site; road-base and surfacing materials will be removed and placed on <br />the shaft pad; and the shaft pad and access road disturbance areas will be regraded to reestablish effective drainage <br />and blend with the surrounding terrain. Cover over any cuttings remaining in the cuttings pit will be a minimum of <br />2 feet of suitable material, and the postmining configuration will approximate the premising contours. As-built <br />certification will be provided to the CDMG following fmal closure, backfilling, and grading of the cuttings pit. <br />Any excess road-base and surfacing materials not required to reestablish approximate original contour will be <br />hauled off-site and disposed of. Stockpiled and windrowed topsoil will then be replaced on those disturbed areas <br />where it was previously removed and seeded with a pastureland seed mixture. <br />6-Main North Ventilation Shaft and Mine Water Storage Reservoir (TROS=48 TR07 61 TR07 62 MR06- <br />208. MR06-210, MR06-212 MR07-224) <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 <br />will be removed and reused at another locale, salvaged, or disposed of off-site. Buried utilities will be stubbed-off <br />below grade and abandoned. Concrete pads will be broken up, and foundations will be demolished to at least 2 feet <br />below grade, and the resulting concrete debris will be disposed of in the shaft opening. The shaft collar concrete <br />will also be broken up and disposed of into the shaft opening, leaving an open space for the concrete slab and <br />backfill materiaUshaft cuttings to be placed in the shaft void. A cement plug will be placed in the bottom 15 feet of <br />the shaft and the remainder of the shaft will be filled with inert material including the shaft cuttings and collar <br />excavation materials. A cement plug will be poured from ten feet below grade to within approximately 3 feet of the <br />surface. The remaining 3 feet will be 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 <br />above ground surface would be cut-off flush with or below natural ground level. Utility boreholes will be <br />plugged, filled to within 10 feet of the ground surface with inert material, and a cement plug will be poured from <br />the top of the fill to within approximately 3 feet of the surface. Any surface casing will be cut-off below grade, <br />and the remaining hole will be filled with soil material and graded to blend with the surrounding terrain. <br />The site geotechnical auger-holes and test pits were backfilled and leveled, and piezometers were either removed, or <br />plugged, cut-off below the ground surface, and capped with a clay or cement cap immediately following completion <br />of field investigations. The associated disturbed areas were seeded with the pastureland seed mixture within 6- <br />months of completion of the geotechnical investigations. Following removal of structures and equipment, and <br />plugging and sealing of the shaft and boreholes, any cuttings remaining in the temporary mine waste disposal pit <br />will be covered with excavated shaft collar material; road culverts will be removed and disposed of off-site; road- <br />base and surfacing materials will be removed and placed on the shaft pad; and the shaft pad and access road <br />disturbance areas will be regraded to reestablish effective drainage and blend with the surrounding terrain. Cover <br />over any cuttings remaining in the cuttings pit will be a minimum of 2 feet of suitable material, and the postmining <br />configuration will approximate the pre-mining contours. As-built certification will be provided to the CDMG <br />following final closure, backfilling, and grading of the cuttings pit. Any excess road-base and surfacing materials <br />not required to reestablish approximate original contour will be hauled off-site and disposed of. Stockpiled and <br />windrowed topsoil will then be replaced on those disturbed areas where it was previously removed and seeded with <br />a pastureland seed mixture. <br />MR09-235 2.05 - 106 02/16/09 <br />