An unplanned roof fall has occurred on the No. 1 Old North panel in No. 4 entry at spad location 1164 to 1172. This fall is approximately 60 feet long and 7 feet in height and 18 feet in width. 6 foot torque tension bolts were used when this area of the mine was developed in September 2010. No employees were injured or equipment was involved. This fall does not effect ventilation.