FILE - In this Nov. 9, 2010 photo, a mine employee stands in the entry of the Signal Peak Energy's Bull Mountain mine in Roundup, Mont.
FILE - In this Nov. 9, 2010 photo, a mine employee stands in the entry of the Signal Peak Energy's Bull Mountain mine in Roundup, Mont. Janie Osborne AP
FILE - In this Nov. 9, 2010 photo, a mine employee stands in the entry of the Signal Peak Energy's Bull Mountain mine in Roundup, Mont. Janie Osborne AP