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The haul road has been designed to include construction and maintenance of ditches to provide <br />positive drainage along the entire length of the road. <br />Water Management. Water is a major factor in most landslides or areas of potential surficial • <br />instability. Proper drainage is essential in correcting or eliminating slope failures. Surface drainage <br />within the potentially unstable area can serve to facilitate drying out of the material and therefore <br />reduce the chances of further movement. In the "neck" area of Section 17, where topsoil has been <br />removed, water was not observed except as rivulets in response to snowmelt/rainfall. However, <br />surface water runoff will be controlled and positive drainage maintained along the proposed haul road <br />to eliminate future saturation of materials. Mining in this area will tend to further reduce the potential <br />for saturation of surficial materials, providing for direct discharge of any shallow groundwater from <br />adjacent areas to the pit excavation. <br />Conclusion. The area to the north of the "neck" area of Section 17, included in the area mapped as <br />Qols, has been disturbed for a number of years and contains an electrical substation and Topsoil <br />Stockpile C. Since the topsoil has been removed (1995/1996) from the neck area, no instability or <br />movement has been observed in the area. No significant active or recognizable instabilities were <br />observed during the topsoil removal in the "neck" area in the fall of 1998. Topsoil Stockpile H has not <br />experienced any movement during the spring of 1999 lone of the wettest springs in the last several <br />years). <br />In summary, SCC believes that "unloading" through topsoil removal has provided additional stability to • <br />the area and the area will be "safe" for mining and the haul road location. However, SCC will agree to <br />continue to monitor the conditions within the "neck" as the area is mined. <br />Coal Resource Protection and Conservation <br />Mining at Yoast involves extraction of two separate coal seams (the Wadge and the Wolf Creek <br />seams) having varying overburden depths. The initial choice of mining equipment type and size was <br />based upon the type of mining conditions, production requirements, the life of the mining operation, <br />types and thicknesses of overburden, local and regional dip, and thickness of the coal seam. <br />Experience in mining at Yoast has resulted in the anticipated mix of excavation and support <br />equipment. Auxiliary equipment has been matched to the primary excavator and its capabilities. <br />Mining activities are conducted to maximize the recovery of coal while maintaining environmental <br />integrity. <br />During reserve development, all the coal encountered during drilling is recorded. The correlatable and <br />estimated mineable seams are cored and analyzed. These data are utilized to finally determine <br />mineable reserves. The quality of the seams as well as their occurrence in the geologic column is • <br />considered when determining whether the seam is mineable or nonmineable. <br />TR-25 9c Revised 4/04 <br />