An unintentional roof fall was discovered at approx 10:45am at brk 77 on Grassy Creek mains. All approaches to the fall were timbered off. Fall did not interrupt ventilation, will not be cleaned up. Fall was approx 6-8' high, 20' wide & approx 143' long. Fall was halfway between 6 & 7 entry, thu the intersection of #7, up #8 entry for approx 15'. The fall is Y shaped.