A ROOF FALL OCCURED IN MMU-0010, 2ND NW MAINS ENTRY O @ SURVEY STATION 2+10. THE FALL MEASURED 40'LONG X 10'WIDE X 6'HIGH. THIS AREA HAD BEEN BOLTED WITH 9'DOUBLE LOCK BOLTS & 6'FULLY GROUTE D BOLTS. ALL APPROACHES TO THIS AREA HAVE BEEN TIMBERED OFF.