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Fish Creek Ventilation Shaft and Dewatering and Water Treatment Installation (MR07-216, NM16-297) - The
<br />Fish Creek Ventilation installation had a useful life of approximately seven years, until the first set of longwall
<br />panels were mined -out. The fan building, duct -work, and fan have been removed from the site. The borehole was
<br />temporarily sealed, as described in the response to Rule 2.05.4(2)(g), and was used only for discharge from the
<br />excess flow diversion line from the Fish Creek water treatment system. In 2007, the shaft installation was modified
<br />for use as a dewatering well to replace the inoperable Fish Creek South Dewatering Borehole.
<br />On completion of mining, and when the system is no longer required, all facilities will be removed and the site
<br />reclaimed. Removal of the surface facilities will involve removal of the modular electro -coagulation units (2);
<br />dismantling of surface structures, which includes the powerline, transformer and pad, any remaining chemical and
<br />pump control equipment, buildings and pads; fencing,; stubbing -off and capping buried piping; and demoilition of
<br />building foundations. The concrete demolition debris will either be hauled to the refuse site for disposal or hauled to
<br />a landfill.
<br />Final reclamation of the dewatering wells and ventilation shaft will involve excavating down 4 feet from grade
<br />around the casing, cutting off the steel casing 3 feet below grade, hanging steel decking from the top of the cut-off
<br />casing (this decking will be 30 feet below the top of the cut-off casing), placement of 30 feet of concrete in the
<br />casing (for a 3 -foot diameter cased hole, the 30 foot x 3 foot diameter cement plug would weigh approximately
<br />32,000 pounds, which would be more than adequate to resist the calculated hydrostatic pressure and provide an
<br />effective seal). The remaining 3 feet will be filled with soil, and graded to blend with the surrounding terrain. . The
<br />access road will be graded to blend with the surrounding terrain, and the culvert will be removed.
<br />After the facilities are removed, any accumulated sediments in the treatment ponds will be removed or buried, if
<br />appropriate, based on testing and characterization; the pond basins and all other facility areas will be backfilled and
<br />regraded to blend with the existing terrain; and the stockpiled soil material will be redistributed over the area. The soil
<br />material stored adjacent to the site will be redistributed over the dewatering site and reclaimed road segments and will
<br />be seeded with the pastureland seed mixture. Approved permanent access roads will remain intact for use by the
<br />surface owner. During the 10 -year liability period, TCC will maintain the road for monitoring purposes. After bond
<br />release, the land owner will assume responsibility for the road. The northern short section (2,500 feet) of the access
<br />road will be reclaimed unless otherwise approved by the CDRMS. The soil windrowed or stockpiled adjacent to the
<br />road will be seeded with the rangeland seed mixture.
<br />Rockdust Tank - After removal of the rockdust tank and cement pad, the pit -run gravel of the truck access/unloading
<br />area will be dispersed across the .5 acres of disturbance. The area will be ripped before the stockpiled soil is reapplied
<br />and reseeded.
<br />7 -North Escape Shaft - When the facility is no longer required, the shaft will be plugged, and the site graded, re -
<br />soiled, and revegetated. Steps required to abandon the shaft will include removal of surface structures, demolition of
<br />the concrete foundation and piers, and sealing of shaft. After the surface structure is removed, the broken -up
<br />foundation and piers will be put down the shaft, and decking will be suspended in the shaft 10 feet below -grade. The
<br />support beams and decking will be suspended from the steel casing by steel straps (i.e. I -beams or similar support
<br />structures) welded to the support beams. The steel straps will be welded to the existing 48 -inch diameter casing. Once
<br />this is completed, a 24 -inch thick reinforced concrete slab will be poured in-place over the previously placed decking.
<br />The void from the top of the concrete slab to within 5 feet of the surface will be backfilled with inert fill material
<br />(approximately 1.4 CY) from the surrounding area. The next 2 feet of the shaft will then be filled with concrete to
<br />form a surface plug for the shaft. Suitable fill material will be placed in the remaining 3 feet of the shaft
<br />(approximately 1.4 CY), and then the site will be re -soiled and revegetated. The redistributed soil will be seeded
<br />with the pastureland seed mixture.
<br />NMD Power Borehole - Upon completion of mining, and when the power borehole is no longer needed, the facilities
<br />will be removed and the site reclaimed. Removal of the surface facilities will involve dismantling of surface structures,
<br />which includes the powerline, transformer and pad, road and culvert, and building. After the facilities are removed, the
<br />site will be regraded to blend with the existing terrain, the stockpiled soil will be redistributed over the area, and the
<br />MR16-297 2.05— 106.2 06/06/16
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