FALL OF ROOF OR BACK at Red Bone Mining Company
A brow in the #17 crosscut of the intake primary escapeway fell and rolled into the entry. The brow was 6' x 5' x 4' thick and impeded travel in the entry. Two (2) 4ft resin bolts were pulled out when the brow fell. After examination by a certified employee, floor to roof support, in the form of wooded cribs, were built to support the area and the rock was removed.
U.S. Mine Safety and Health Administration