AN UNINTENTIONAL ROOF FALL OCCURRED ON THE MMU 004-0 #3 ENTRY #1 CROSSCUT OUT BY ACTIVE PILLAR LINE AT SURVET SPAD #1717. THE FALL MEASURED APPROX 18' LONG BY 18' WIDE BY 6' HIGH. THE FALL AR EA HAD BEEN SUPPORTED WITH 6' POINT ANCHOR BOLTS. NO EQUIPMENT OR VENTILATION WAS AFFECTED NOR WILL THE FALL BE CLEANED UP.