AN UNINTENTIONAL ROOF FALL OCCURRED IN THE 4-WAY INTERSECTION OF ENTRY #3 @ 71+70 ON THE 6TH NORTH. THE FALL 35'LONG X 20'WIDE X 4'THICK DID NOT IMPEDE TRAVEL OR IMPAIR VENTILATION. THE ROOF W AS SUPPORTED BY 4' FULLY FRONTED ROOF BOLTS. THE AREA WAS DEVELOPED IN JULY OF 2001.