AN UNINTENTIONAL ROOF FALL OCCURRED IN THE 4 WAY INTERSECTION OF ENTRY #6 ON THE MMU 0010 AT 3 & 70. THE FALL 24' LONG 22' WIDE AND 6' THICK. DID NOT REPAIR VENTILATION OR IMPDED TRAVEL. THE R OOF WAS SUPPORTED BY 4' FULLY GROUTED ROOF BOLTSL CRIBS. THE INTERSECTION WAS DEVELOPED ON 10-7-00. 70' CENTERS.