AN UNINTENTIONAL ROOF FALL OCCURRED IN THE #4 ENTRY ON A-3 MAINS (1) BREAK OUTBY SPAD #5028. SIZE OF FALL WAS ESTIMATED TO BE 20'L X 20'W X 2-4'H. AREA HAD BEEN SUPPORTED WITH 48"" FULLY GROUTE D RESIN BOLTS. NO INJURIES, A-3 BELT LINE WAS CAUGHT, VENTILATION WAS NOT INTERRUPTED. FALL WILLCLEANED UP.