FALL OF ROOF OR BACK at Mammoth Coal Co.
An unplanned roof fall has occurred at brk. 16 of 1st S.W. Panel. The nearest spad is #1141. Fall was approx. 25' long x 18' wide x 12 to 15' high. There were no injuries involved and the fall did not affect ventilation or travelways.
U.S. Mine Safety and Health Administration