AN UNINTENTIONAL ROOF FALL OCCURRED AT #4 BREAK ON C-MAINS. THE FALL WAS ESTIMATED TO BE 45' L BY 18' W BY 8' HIGH. FALL STARTED IN 2 LEFT BREAKEXTENDING OVER TO #1 ENTRY, AREA HAD BEEN SUPPOR TED WITH 4' FULLY GROUTED RESIN BOLTS. NO INJURIES, NO EQUIP CAUGHT, VENTILATION WAS NOT INTERRUPTED.