A roof fall 7'L x 19'W x 8'H was discovered outby spad 66570 #4 entry crosswise to the #6 entry. The fall was caused by failure above the anchorage zone of the 5' torque tension roof bolts. The area was developed 4/6/2011 and was 10,000 feet from the face area. Ventilation and the transportation of miners' were not affected. No injuries occurred.