Saturday, as 481 was leaving the ash pit, she had to cross an area of vehicle packed snow, and the pilot truck derailed. Lots of dedicated work by the crew, with a great deal of frustration due to 12" of fresh snow causing the wedges and blocks to slide (even with shoveling)they got her back on the track. 486 was readied while rerailing efforts were going on. 481 Departure was approx 1:00pm. We arrived at Cascade Wye, turned the train and backed to MP 478.44 (Site of Cascade Siding) where the box car of sheep were waiting to be released. Forty seconds later they were gone and approximately 200 people saw the release and then returned to Durango. The Canyon was spectacular with about 18" of fresh snow. Not one complaint was heard. Train arrive Dgo at 7:00pm.