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BME has monitored Red Wash during active subsidence. The schedule for monitoring Red Wash was tied to monitoring nine alluvial wells established in Red Wash. When the longwall face advanced to within 200 feet of the Red Wash alluvium, tension cracks that might appear on the surface were searched for on a schedule of once every two weeks. This schedule continued until the longwall face advanced past the alluvium 400 feet. After the longwall advanced more than 400 feet past the Red Wash alluvium, surface crack monitoring resumed at a schedule of once every two months to coincide with monitoring of the nine alluvial wells. No interruption in the flow of water to the White River occurred. Scullion Gulch will be visually monitored several times a week unit retreat has proceeded a distance from the channel equal to at least the depth of the seam. There will be no mining beneath any known aquifer that serves as a significant source of water supply to any public water systems and there will be no mining beneath any public buildings, residential structures, urbanized areas or towns. I.A.6.g Subsidence Effects on the Powerline. A need to re-orient the mine plan impacted the initially proposed non-subsidence corridor. Either considerable longwall tonnage would be eliminated or the concept of anon-subsidence corridor had to be abandoned. To ensure that maximum economic recovery of the coal is achieved, BME chose the latter alternative. As discussed elsewhere, the waterline will be protected from subsidence either by relocating underground or constructing an offset line to bypass any affected portion of the waterline. However, relocation of the 138-Kv powerline was not economically feasible and portions of the powerline were allowed to subside with mitigative measures in place. In actuality no effect of subsidence was noted on the waterline during the mining of LW-1 to LW-5. An analysis of subsidence effects on the 138-kV powerline indicated that some of the pole structures would be affected by the subsidence. The worst possible consequences of subsidence to the power line would be the interruption of power supply to the mine. The consequencesof such a power failure would be the same as those experienced in past power failures -the mine would be evacuated of all personnel until the power supply is reestablished and all safety procedures determine that the mine is safe to reenter. There are a total of 28 structureswithin the permit boundary on the 138-kV powerline. Of this total, 11 structures are in positions where they may be affected by subsidence. The structures are bolted wooden two-pole structures with connecting crossbraces. BME owns the structures and lines and is the only customer served by the powerline. Rio Blanco County Special Use Permit #81-1 Exhibit B -Mining Plan September2000 '12