An unintentional roof fall was discovered on 2 SW Mains in #6 entry(intake) S.S.1201, approx. 2500' off the working section. The fall measured 40'L x 8'H x 18'W. The cause of the fall appeared to be a slip with a coal rider seam and shale roof. This fall does not interfere with ventilation or with escape travel and will not be cleaned up at this time.