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These cuttings were mixed with coal during conveyance from the mine and therefore will be washed to recover the <br />coal. It is anticipated the cuttings and coal will comprise 5-] 0 percent of the monthly volume of low-quality coal <br />processed through the wash plant. The cuttings will then be part of the refuse stream coming from the plant. The <br />fines generated during the washing process of the cuttings/coal will be discharged underground as part of the <br />thickener underFlow. The course segment will be placed in the refuse pile. Given the fact that the fines from the <br />cuttings/coal will be processed through the plant and the fines disposed of underground in the thickener underflow, <br />it is not necessary to conduct a geotechnical analysis of the material going to the refuse pile. The fine segment was <br />the reason for committing to conducting a geotechnical analysis, but they will no longer be placed in the refuse pile. <br />TCC has washed some of the cuttings from the ventilation shaft boring, but has found it not to be very efficient. <br />Based on this, TCC is planning to haul the remainder of the borings, unless they contain significant amounts of <br />coal, to the refuse pile for disposal. A geotechnical analysis of the cuttings was performed by NWCC and a copy of <br />the reports is presented in Exhibit 25a-2. It demonstrates that the cuttings can be placed in the refuse pile without <br />impacting its stability. <br />Once the cutterhead breaks through to the surface within [he shaft collar, the cutterhead drive-unit and temporary <br />headframe will be disassembled and removed from the site. A permanent shaft casing consisting of steel ring- <br />beams and liner plate will be placed and the annulus between the liner and the shaft bore will be cemented in <br />segments after boring operations have progressed to the surface. <br />The cement shaft liner will serve to isolate the Twentymile Sandstone from the Wadge Overburden. Additionally, <br />it is planned to pressure-grout the Twentymile Sandstone to prevent seepage from it into the shaft. This will further <br />assure that, after final closure, the water in this unit will be confined and not seep down on the inside of the shaft. <br />Following completion of shaft boring and casing operations and removal of equipment from the site, the fan <br />enclosure (fan shroud) and electrical control building will be erected on either the previously constructed or new <br />concrete pads, and the fan, fan drive motor, and electrical control, monitoring, and communication systems will be <br />installed. Average pad thickness will be 2 feet and total pad surface area will be approximately 3,100 sf. The <br />installed axial-vane exhausting ventilation fan has a capacity of 800,000 cfm with a 3,000 hp drive motor. A fence <br />will be constructed to enclose the fan installation. Following commissioning, the shaft pad site and access road will <br />be cleaned-up and surface areas graded and dressed. <br />In addition to the main vent shaft, up to two additional holes will be cased to allow for power drops and other <br />ancillary uses into the mine. If two holes are cased they will have a nominal internal diameter of 4 or 8 inches; if <br />only one hole is cased, it will have a nominal diameter of 13 inches. When the holes are no longer needed they will <br />be grouted from the bottom of the casing to within three feet of the surface. The remaining four feet of casing will <br />be cut off and discarded and then the area graded, topsoiled and seeded as per the approved plan. The holes will be <br />located within the existing vent shaft pad disturbance area. <br />Concurrent with road construction a power distribution line will be extended from the existing substation to the <br />pad-mounted transformer at the shaft site. The power distribution line is approximately 3,600 feet long with a total <br />of 12 powerpoles. <br />In order to minimize potential environmental and aesthetic impacts associated with the NW Mains ventilation shaft <br />and fan installation, surface drainage at the shaft site will be handled by an upgradient diversion ditch, perimeter <br />berms, and gravel surfacing under an SAE, the limited road drainage will be handled by designed drainage <br />structures, active use areas are graveled to control dust and drainage, other disturbed areas (including topsoil <br />stockpiles) will be stabilized with temporary vegetation, and structures will be painted in neutral earth-tone colors <br />to blend with the natural surroundings. <br />As shown on Map 23, additional entries will be driven to the north from the ventilation shaft site. These entries <br />~uil1 k~, weeded to maximize tkve e€fvcieacy of tktie ves~tila4ios~ system. "S4te es+tsies v~itl FR, dsi~em 4a tkve, sasrR, mas~vrs <br />as is used in TCC's development work, i.e. continuous miners and shuttle cars. <br />MROS- 192 2.05-45.2 03/22/05 <br />