AN UNINTENTIONAL ROOF FALL WAS DISCOVERED IN THE 1ST N. SUB-MAINS, XC-19, ENTRY NO. 5 APPROX. 12' L x 10' W DOME. THE AREA WAS BOLTED W/5' RESIN GROUTED BOLTS PRIOR TO OPERATORS CHANGE IN ROOF CONTROL PLAN TO 6' RESIN GROUTED BOLTS. THE FALL HAS NOT IMPEDED TRAVEL, AIR OR ESCAPEWAYS. THE AREA HAS BEEN TIMBERED AND DANGERED OFF.