AN UNINTENTIONAL ROOF FALL WAS DISCOVERED BY A SHIFT FOREMAN ON 3 EAST MAINS IN THE #1 ENTRY AT SPAD 18989. APPROXIMATE FALL DIMENSIONS WERE 10' HIGH X 30' WIDE X 40' LONG WHICH INVOLVED AN IN TERSECTION. THERE WERE NO INJURIES NOR EQUIPMENT CAUGHT AS A RESULT OF THIS INCIDENT.