A roof fall occurred in the #11 seam in the 2 East in the intersection of crosscut #5 in #7 entry extending through the pillar line approximately 15 feet towards #6 entry meauring approximately 50ft. x 18ft. x 6ft. high. This area was supported with thirty (30) inch fully grouted roof bolts. An undetected slip was determined to be the cause of the fall.