2nd hand information: Two snowboarders descended Monte Cristo direct at 1030am. At the choke, the first successfully rappelled down and waited for the second to join him below. At that point, a wet loose slide cascaded down upon them from above, pummeling the second who was on rappel while catching and carrying the first over two minor cliffbands. It is not known whether the person on rappel was clipped into the anchor or backed up with an autoblock above or below his rappel device. It is also not known whether the loose sluff was a natural or triggered from above.
After the avalanche, both were able to make it down to the road unassisted.
Photos courtesy Stacee at Powderbird
Monte Cristo is a very steep south facing avalanche path just west of Superior on the Cottonwood ridgeline. Its descent is 3100' down to the Little Cottonwood road.