Mammoth Ski Patrol Deaths Hit Swiftly

By midmorning Thursday, seven of them had set to work digging out a nearly buried fence erected to keep skiers away from one of the mountain's dangerous volcanic vents.

Suddenly, the snow beneath them gave way.

Two of the ski patrollers dropped into a 21-foot maw filled with deadly carbon dioxide fumes and landed on the ground, trapped in a deep hollow.

Their cries rose to the top for a few minutes, then stopped.

Two rescuers went in after them and were quickly overcome by fumes. Others followed. The ordeal lasted barely 20 minutes, but three members of the ski patrol were dead and seven others hospitalized.

In the wake of the deadly accident, officials on Friday were trying to determine how it could have been avoided. One issue is whether the area around the crevasse, known as a fumarole, should have been designated a hazardous confined space, which would have required Mammoth Mountain to keep rescue gear at the site, including breathing equipment and tethered ropes. Investigators from Cal-OSHA were expected to arrive today.

"This is not the first time we've been at this site," Cal-OSHA spokesman Dean Fryer said. "The first time was in 1995 when we were looking at this exact area and helping the ski area understand why it needs to be avoided. The hazards of this location are well known."

Mammoth Mountain Chief Executive Rusty Gregory said Cal-OSHA did not instruct the resort to provide additional safeguards at the site.

"I'm quite sure there are no recommendations from them on dealing with the fumarole or we would have dealt with it and they would have made sure that we did," he said.

Gregory said the hazard was well known and well marked. The site was surrounded by a four-foot tall plastic snow fence and posted with a sign reading: "Closed area. CO2 emission area. Natural toxic gas."

The snow crevasse that claimed the men is part of Mammoth Mountain's volcanic legacy. The mountain is dotted with fumaroles, which release occasional puffs of foul-smelling gases. . During most of the year, the vents are harmless because the carbon dioxide fumes they emit dissipate in the air. But in winter, the volcanic gases pool and concentrate in pockets formed beneath the snow.