On 7/17/2010 an unplanned roof fall occurred on MMU 002 in #6 entry, cross cut #4 in the 1B Submain off the 4th S.E. Sub-Main. The fall was approximately 25' long X 17' wide X 8' thick. It was a non injury accident, and the fall will not be cleaned up. The area was bolted with 8' and 10' roof bolts.