Originally Posted By: dbd
Originally Posted By: Harvey Lankford
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The Mammoth incident sort of proves the point doesn't it? These were knowledgeable ski patrol people who got close to the edge of a known (steam) hole and the edge caved in. Is that right?

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Harvey


I think the problem with this incident was that the steam hole does not normally cover over, but continues to maintain an opening as snow falls. This time a rare high accumulation rate managed to cover the hole. When the patrol went out to set up the usual flagging around the vent there was no hole marking the vent. While they were putting up the markers, the cavity collapsed.

Overhanging powder is a tough climb out and a tough extraction to rig even if you can stand upright.

Dale B. Dalrymple


yep, plus it was not just steam, but poisonous volcanic gasses, which overcame the patrollers within a very short time (<2 min as I recall). I believe one guy jumped down to help and was lost.

Here's an article:

http://www.mammothlocal.com/news/3_ski_patrollers_die.php