A roof fall occurred on the #1 Portal Bottom on the #2 supply track. The fall was located at 5+80 feet. Fall was 40 feet long x 20 feet wide x 6 feet high. Area was mined in October, 1971. Fall occurred due to the deterioration of the immediate roof. Area was supported with 8 feet and 10 feet conventional roof bolts. Fall blocked the passage of material on the track.