Pretty nifty find. The list of animals has me thinking someone should get cracking on some song lyrics.
Some earlier articles about the initial find by the guys digging the reservoir indicate that at least one of the mammoths was buried in peat which would account for the preservation (rather than fossilization) of bone and hopefully some soft tissue.
Widespread Panic fans will be interested to learn that Snowmass Village at least considered making "Big Wooly Mammoth" the official village song.