2016-06-08_PERMIT FILE - C1982056A (4)

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The drainage ditches around the pile, and the lower segment of the coal refuse haulroad have been constructed consistent with approved designs. Soil materials were salvaged from the entire footprint of the waste pile. The soil was isplaced in soil stockpiles SF -12, SF -13 and SF -14. On completion of these preparatory activities, the toe drain was installed consistent with the designs presented in Exhibit 26A. During construction of the waste pile, the benches will be constructed consistent with the recommendations presented in Exhibit 26A and 26A-1. These recommendations include constructing the waste pile in compacted lifts not exceeding 2 feet thick and, during inclement weather, stockpiling material within the footprint of the waste pile. This allows for the material to drain and then be spread under more favorable weather and moisture conditions. Exhibit 26A-1 modified Exhibit 26A by revising the construction sequence and removing the concept of a compacted zone fill. The entire lift will be constructed as one lift without having to construct an A segment and then a B segment. This will increase the stability of the pile by eliminating a potential slip -plane between the two segments. Also, the existing road accessing the refuse pile will be utilized as long as possible to provide access to the southern portion of the pile. The road will be constructed consistent with the recommendation presented in Exhibit 26A-1, including keying in road fills, and the road corridor will eventually be filled with refuse material. A portion of the cover material to be placed over the waste material will be native clays and subsoils located within the footprint of the pile. Currently, some of these materials have been excavated from the toe drain and from within the footprint of the waste pile. These materials are stockpiled along the northeast toe of the refuse pile and adjacent to the old pit. As the waste pile expands in size, additional cover material will be excavated from within its footprint. This material will either be placed directly on a finished face of the pile or stockpiled adjacent to or within the pile footprint. Cover material will be placed over the finished face of each bench, and compacted, then soil will be redistributed and seeded with the pastureland seed mixture. Any voids left by excavating the cover material will be filled-in with waste material, thus increasing the amount of material that can be placed in the pile without increasing its footprint. The replaced cover and soil will be maintained within 1 bench of each completed bench. This will provide a buffer between the active bench and previously completed benches. The outslope of the bench will be covered during the first . available period providing suitably dry conditions for placement. Cover material will be direct placed, to the extent possible, particularly during the initial and middle construction phase of the pile. As the pile nears completion, a stockpile of cover material may be required to provide sufficient material to complete the pile. Following placement of cover material, soil will be placed over the cover material, with direct placement again utilized to the extent possible. Soil from stockpile SF -6 will be used initially over completed portions of the waste pile outslope area to facilitate the final alignment of the perimeter drainage channel in the vicinity of stockpile SF -6. While soil from stockpile SF -6 is being utilized, additional soil that must be stripped will be stored in stockpile SF -12. During the final phases of the waste pile construction, soil which could not be direct placed, will be redistributed on the pile from stockpile SF -12. Equivalent yardage from the waste pile utilization of soil pile SF -6 will be substituted as necessary from stockpile SF - 12 to cover the office area, road corridor, tipple area, original waste rock dump, and batch -weigh loadout facilities areas originally slated to be re -soiled from pile SF -6 (see Map 29). Soil will not be placed on any constructed waste pile drainage terrace until the adjacent outslope above the terrace is completed and cover material is applied to the upper outslope surface. In this manner, the potential for waste material to contaminate replaced soil will be minimized. Southwest District Ventilation Borehole, Powerline and Access Road The Southwest District Ventilation Borehole, Powerline and Access Road required a minor amount of work in order to reclaim the sites. The work included building and duct -work removal, fan removal, demolition of concrete pads, removal of concrete, permanently sealing the shaft opening, powerline and pole removal, road removal, soil material replacement, and seeding. Final reclamation of the 36 -inch diameter casing involved placing a five-foot cement plug at the bottom of the cased hole. The casing was backfilled from the plug to within 10 feet of the surface. The top 3 feet of the casing was cut off, a 7 foot cement plug was placed in the remaining casing, and the remaining 3 -feet backfilled with • subsoil. The access road was graded to blend with the surrounding terrain, and the culvert removed. The ventilation borehole pad and access road were re -soiled and seeded with the appropriate seed mixture. RN08--05 2.05-103 03/12/10