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poor sections of the deposit and it is possible to negotiate geologically disturbed areas of the mine and <br />easily adapt to variations in the seam. The continuous mining system has great flexibility. The <br />equipment can be easily moved around to different locations in the mine and the overall system is only <br />minimally affected by a stoppage of any one unit. <br />The production from each continuous miner section is relatively small and this mining system is <br />generally more hazardous and more expensive to operate than a longwall system. The overall coal <br />reserve recovery from room and pillar mining seldom exceeds 55 percent because all of the pillars <br />cannot always be safely extracted. <br />I.A.2.b Longwall Mining. Longwall mining has gained great acceptance in the United States. It has <br />gained great acceptancebecause of its three apparentadvantages: <br />1) High recovery <br />2) High production <br />3) High safety <br />In longwall mining, coal is extracted from panels that are several thousands of feet long and several <br />hundreds of feet wide. The shearerwhich is a powerful cutting machine with a huge drum on each end <br />rips a strip of coal from the longwall face. The coal falls onto a face conveyor consisting of flexible <br />steel pans which transfers the coal away from the longwall. As the shearer passes, the roof supports <br />are advanced immediately and the roof behind them is allowed to cave. When the shearer returns on <br />the cleanup pass, the face conveyor is pushed forward and the cycle is ready to be repeated. <br />Because longwall mining usually extracts the entire seam height in a solid block of coal, coal reserve <br />extraction is usually extremely high. Extraction as high as 90 percent has been achieved with longwall <br />mining methods, and 70-80 percent recovery is average. <br />The average production from longwall faces is about 5,000 tons per shift. However, many new faces <br />including the face started by BME have exceeded 10,000 tons without difficulty and new equipment <br />and technology promises to raise future production even higher. Because longwall mining is believed <br />to be the only true continuous mining system the tonnage mined by this method is expected to climb <br />during the coming years. The Deserado Mine has the reserves and the coal blocks suitable for this <br />high recovery, high production technology. <br />Rio Blanco County Special Use Permit#81-1 <br />Ezhibit6 -Mining Plan <br />September2000 <br />3 <br />