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1987 PRODUCTION AND GEOLOGIC CONDITIONS Colorado Westmoreland Inc. produced approximately 450,000 tons of coal from the Orchard Valley West Mine in 1987 from Federal Coal Lease C-37210. CWI experi- enced a similar production rate in 1986. However, the 1987 production was for a twelve month period whereas the 1986 production ceased just prior to the June 1 fire that resulted in the sealing of the Orchard Valley Mine. All of the 1987 production was obtained from a single unit of equipment. Nearly all other equipment was sealed in the Orchard Valley Mine. Mining at the Orchard Valley West Mine during 1987 consisted entirely of new de- velopment including the completion of three new portals and submain development. This development occurred in the First West Submains advancing west, the South III Submains advancing primarily north, and the Second West Submains advancing east toward the Orchard Valley Mine. Mining in the Orchard Valley West Mine was conducted in the same manner as planned for the Orchard Valley Mine. The dif- ferences were the access and the direction of advance. The Rock Slope portals and entries were designed and permitted in the Spring of 1987. Originally, the Rock Slopes were planned to connect with the Orchard Val- ley West Mine in June, 1988, approximately 18 months after the initial develop- ment of the new mine. Access for men, materials, conveyor haulage, and ventila- tion to the Orchard Valley West Mine could then be via the rock slopes. The Or- chard Valley West Mine portals would then function as additional escapeways and for ventilation. However, the rock slopes construction was indefinitely post- . poned due to poor market conditions and also as a result of a court decision al- ~ lowing our only customer to take less coal than anticipated. The geologic and mining conditions observed varied somewhat throughout the areas during 1987 development. Conditions were similar to those in the Orchard Valley Mine and were influenced by seam thickness, "D" seam interburden thickness, overburden depth, local lithology, and some minor encounters of water. A de- scription of these conditions is summarized as follows: First West Submains Mined length: Sub main type development was advanced west for approxi- mately 1,300 feet. Overburden thickness: 100 - 450 ft. Mining height: 8 - 9 ft. (10 - 11 ft. in the portal area). Roof: Comprised of siltstones, shales, and carb. shales. Slickenslides and Fractures were very minor resulting in a consistent and compe- tent roof. Ribs: Little if any rib sloughage was encountered. Floor: The "D" seam interburden served as the floor. The interburden consisted of carb. shales, shales, and some minor sandstones . which provided a Fairly competent floor. Interburden in the area was 18 - 24 inches thick.