Two of my good buddies live in Salt Lake, they both grew up there and are excellent skiers. They do a trip every year, and last year did a backcountry expedition in Canada with a few guides. Their group was caught in an avalanche, and luckily everyone survived, but it was, obviously, very scary. Here is a recap of their experience if you're interested:

http://evalogue.life/near-tragedy-slopes-faith-triumphs/

My friends are Mike Crowton (who related the story to the writer) and Rich (the only snowboarder in the group, who is wearing a yellow jacket and blue pants in the pictures) They regularly ski in the backcountry around Alta and Snowbird, and alternate season passes at either Alta or Snowbird, so they were not naive about the risks and were properly trained.