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1) Permanent entryways - A network of mains and submains consisting of multiple entries are <br />driven to outline the coal deposit (Map 119). These entries, which consist of 4 to 6 openings, <br />are developed on 80-foot centers. They will be permanently supported to withstand caving for <br />the life of the mine. <br />2) Barrier pillars - To ensure that no caving or pillar crushing of the mains occur due to adjacent <br />mining, a 300 to 400-foot homogeneous barrier pillar will border all mains and submains, and <br />200 to 300-foot barrier pillars will be left in place to separate adjacent continuous miner pillar <br />sections. <br />3) Chain pillars -Each longwall will be bordered along the length of the panel by two rows of <br />chain pillars. Chain pillars are sized to minimize subsidence and provide a safe mining <br />environment. The size of chain pillars is determined primarily by seam depth and seam <br />thickness and will be adjusted as these parameters change. The ends of the longwalls will be <br />separated from the mains by one 200-foot barrier pillar. <br />4) Abandoned coal -There are several areas within each coal seam where specific coal areas <br />will be abandoned due to geological and physical mining problems. <br />I.A.6.d Damage Mitigation. While problems with surface cracking have been minimal to date, BME <br />will recompense in full any loss of livestock caused by subsidence effects to any surface owner or any <br />rancher leasing surface areas from the government. Should the number of tension cracks above a <br />particular longwall present a safety hazard, BME will fence off the area above the active mining until <br />completion of the panel. Any stock ponds or reservoirs damaged by subsidence will be repaired as <br />necessary. <br />Rio Blanco County Road 65 crosses diagonally over an area above the mine where subsidence is <br />expected. The subsidence prediction study indicates that the maximum horizontal tensile strain of <br />about 6600 micro-strain over the D-Seam mine and 11,300 micro-strain over the B-Seam mine will <br />occur where County Road 65 crosses above LW-10 and LW-2B. This amount of strain could disturb <br />the road. BME plans to conduct an ongoing monitoring and maintenance program in addition to <br />posting speed limit and subsidence-hazard signs whenever coal is extracted under the county road. <br />County Road 65 will be monitored daily while mining below it and during the active subsidence period. <br />Any damage will be repaired; including any cracks that could create a safety hazard or delay traffic. <br />BME contends that there will be no damage to the building structures in the permit area, and the only <br />other use of the surface above the mine is for access and limited sheep grazing. Therefore, any <br />Rio Blanco County Special Use Permit #81-1 <br />ExhibitB -Mining Plan <br />September2000 <br />~0 <br />