AN UNPLANNED ROOF FALL WAS DIACOVERED IN THE INTERSECTION OF THE #6 ENTRY OF 7 INTAKE AIR ENTRIES 5 CROSSCUTS INBY BEP #9. THE FALL MEASURED APPROX. 20' WIDE X 20' LONG X 4' HIGH. THE AREA WAS NOT BEING USED AND WAS DANGERED OFF. THE FALL HAD NO AFFECT ON VENTILATION.