A ROOF FALL WAS DISCOVERED IN THE #6 ENTRY, RETURN AIR COURSE AT 7+00, MEASURING 45' LONG, 20 WIDE AND 7' HIGH. THE AREA HAD BEEN BOLTED AND TIMBERED. THIS WAS IN THE SOUTHWEST SUBMAINS. THERE WAS NO INTERUPTION OF VENTILATION, NOR TRAVEL. THERE WAS NO INJURIES.