2014-10-15_PERMIT FILE - C1982056A (7)

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over any cuttings remaining in the cuttings pit will be a minimum of 2 feet of suitable material, and the postmining configuration will approximate the premining contours. Any required pressure —grout boreholes will be sealed at the time of construction. Cement grout will be pumped through the boreholes to seal any wet zones encountered and the boreholes will be filled with grout and allowed to set -up on completion of grouting operations. Any surface • casing extending above ground surface would be cut -off flush with or below natural ground level. Any road culverts will be removed and disposed of off -site; road -base and surfacing materials will be removed and placed on the pad area; and the pad and actress road disturbance areas will be regraded to reestablish effective drainage and blend with the surrounding terrain. Any excess road -base and surfacing materials not required to reestablish approximate original contour will be hauled off -site and disposed of. Stockpiled and windrowed topsoil will then be replaced on those disturbed areas where it was previously removed, and seeded with the appropriate seed mixture. Exploration Boreholes TCC has, over a period of years, completed numerous exploration boreholes to delineate and characterize coal reserves and associated overburden/interburden characteristics. In general, prior to application of the "Notice of Intent" (NOI) process, drilling, completion, and reclamation of exploration boreholes within the Mine Permit Area were addressed within the Mining and Reclamation Plan document. Once the NOI process became widely accepted by both the CDMG and mine operators, most coal exploration activities have been handled under NOI applications and approvals, separate from the mine permitting process. The following briefly summarizes historical exploration information that was previously included (MR97 -154 and PR03 -06) in the Foidel Creek Mine PAP: Permit Rev. Holes Depth/Diameter Pad Size MR87 -5 10 100 - 1,400'/5 5/8" MR91 -61 MR91 -66 • MR95 -113 • 1,500'15 5/8" ? ?/7 5/8" 1,500'/8" 100'x100' 100'x100' 50'x100' Other Relevant Information Wadge coal and roof /floor sampling Converted (Monitoring Wells006 -87 -1, 006 -88 -2) Drillholes 91001 and 91002 Converted (Monitoring Well 91M005) Wadge Overburden Well 91M006 (replaces 91M005) r Converted (Monitoring Well 95M001) Grouted -off above Trout Creek Sandstone For boreholes that are converted to monitoring wells, completion reports were submitted when the wells are finished. The reports document total depth, nominal drillhole size, casing diameter and type, screen size and interval screened, gravel -pack size and length of gravel -pack, formation packer or plug information, backfilling information (cuttings or grout etc.), collar information, and elevation of casing (either TOC or grade). In addition, development information and geologic logs were typically provided. In general, all historic exploration boreholes (whether permitted under the PAP or NOI's) that are not converted to monitoring or water supply wells, are abandoned and reclaimed in the same way. On completion of drilling and any associated geophysical work, a tremie -pipe or drill -steel is used to cement the boreholes from the bottom to within 10 feet of the surface using a cement grout. Any surface casing is cut-off at least a foot below grade, a concrete plug is poured to within.3 feet of the surface, a permanent market is placed in the concrete plug, and the remainder of the borehole is filled with cuttings and/or soil material. Any mud pits are allowed to dry-out and are then backfilled with cuttings and/or excavated material, any excess cuttings are spread evenly over the drill pad surface, and the drill -site and any associated access road are then regraded, topsoiled, and seeded with an appropriate seed mixture. The following is the standard seed mixture used for drill -site reclamation unless another mixture is specified by the CDMG or landowner: TR05 -51 2.05 -120 03/13/06