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<br />III.A.1 Mine Openings The underground access to the coal seams is provided by an open-cut bench <br />and inclined rock tunnels. Across section of a typical mine portal is shown in Figure III-1. <br />III.A.1.a Portal - D Seam This Portal consists of two rock tunnels: one two-compartment tunnel and <br />one single-compartment tunnel. The two-compartment tunnel is separated by a steel divider. The <br />upper compartment contains the coal conveyor belt, and the lower compartment contains an inclined <br />track for transportation of men and materials. The single-compartment tunnel is used for ventilation <br />and to provide a secondary escapeway. These tunnels were driven N23°E until the coal seam was <br />intercepted. Once in the coal, bottom development began during which the number of entries driven <br />gradually increased from two to six. (See Map 119.) <br />III.A.1.b Ventilation Entries - D Seam As soon as bottom development was complete and the West <br />Mains were started, a set of four entries (the South Submains) was started toward the Ventilation <br />Entries. The South Submains were driven at S61°E for about 7300 feet to the intersection with the <br />Ventilation Entries. The Ventilation Entries (2) were driven at S45°W for about 1500 feet to the <br />outcrop. These entries were sealed in 2000 and the surface facilities at the site (a.k.a. East Portals) <br />were reclaimed in 2001. <br />• III.A.1.c Portal - B Seam This portal is located about 100 feet southeast of the northeast corner of the <br />change house. Its design is similar to the D-Portal. It is about 18' wide and 10' high. The slope <br />leading to the B-Seam is about 450 feet long at 8.5° dip. See Map 101. <br />III.A.1.d Ventilation Entries - B Seam The B Seam ventilation will be provided by the same intake <br />fans as the D Seam by way of short rock tunnels. These tunnels will originate in the D Seam West <br />Mains Entries and ramp down to the B Seam. Additionally, a ventilation shaft located approximately <br />4800 feet northwest from the existing D/B Portal. See Map 151. <br />III.A.2 Mining Systems <br />Longwall vs. Room and Pillar Mining BME has designed the mining system to permit the optimum <br />recovery of the coal reserves in the safest and most economical manner. <br />. Midterm Review (8/2002) III-2 <br />