DENVER (AP) -- Six men who set off on a backcountry tour in mountains west of Denver had avalanche gear, had scanned an avalanche forecast, and were hiking toward a safer area to snowboard when they felt a collapse and heard a "whumpf."
Within seconds, the six were swept into a gully, and all but one was completely buried in last weekend's avalanche that was roughly 800 feet wide, 600 feet long and as deep as 12 feet, according to the Colorado Avalanche Information Center's final report on the accident.
With just his lower left arm sticking up from the snow, the lone survivor cleared snow from his face. He struggled to free the rest of his body and screamed for help.
There was no one around to hear him.
"It covered everybody," Colorado Avalanche Information Center director Ethan Greene said Wednesday. "There was nobody left to call 911, nobody left to look for the buried, to help the one person who wasn't buried but couldn't get out."
The man remained stuck for four hours until rescuers arrived, the center's report said.
The state's deadliest slide since 1962 was large enough to bury or destroy a car, the center said. Of the men who died Saturday, one was buried under 10 to 12 feet of snow.
The avalanche was tragic but avoidable, the center said.
The center's report offered new details on the avalanche that occurred as snowboarders and skiers converged near Loveland Pass for the Rocky Mountain High Backcountry Gathering, a day for riding but also avalanche gear and safety demonstrations.
The four snowboarders and a skier who died were all from Colorado. The Clear Creek County sheriff's office identified them as Christopher Peters, 32, of Lakewood; Joseph Timlin, 32, of Gypsum; Ryan Novack, 33, of Boulder; Ian Lamphere, 36, of Crested Butte; and Rick Gaukel, 33, of Estes Park.
Friends identified the survivor as Jerome Boulay of Crested Butte, who has declined requests for interviews.
All had proper avalanche equipment. At least two had avalanche airbags, and some had Avalung breathing devices but apparently were unable to use them, the report said.
"Nobody's immune from getting caught in avalanches. It doesn't matter how long you've been doing this, how athletic you are. ... Everybody can get killed. It's an equal-opportunity hazard," Greene said.
The center has said the avalanche was a deep persistent slab avalanche, in which a thick layer of hard snow breaks loose from a weak, deep layer of snowpack underneath. Colorado Avalanche Information Center forecasters had alerted people about the potential for such avalanches Saturday following a string of April storms.
"If you find the wrong spot, the resulting avalanche will be very large, destructive, and dangerous," the forecast said.
On Saturday, Boulay's group had left the parking lot of Loveland Ski Area, which wasn't affiliated with the backcountry gathering, for a one-hour tour.
They read the center's avalanche bulletin, were aware of the deep persistent slab problem, and aimed to avoid threatening north-facing slopes as they planned to climb a few hundred vertical feet onto northwest-facing slopes, the report said.
But to get to that safer spot, they had to cross a dangerous area, Greene said. They decided to reduce the risk by leaving 50 feet between each person as they trekked. The buffer might have worked to prevent all six from getting swept away all at once, Greene said, but it turned out not to be enough for the large avalanche they triggered around 10:15 a.m.
It took a while for anyone to realize the group was trapped.
Two Colorado Avalanche Information Center highway avalanche forecasters spotted the slide around 12:15 p.m. from Interstate 70. When they reached the scene about 30 minutes later, their avalanche beacons detected no signals. Even with binoculars, they couldn't see tracks heading into the slide area, the report said.
After forecasters drove back to the ski area to ask others at the backcountry gathering whether anyone might be trapped, several people rushed to the scene.
The center urges even expert backcountry enthusiasts to know the conditions, have rescue equipment and get educated on avalanches.
"We owe it to these guys to learn from a really horrible accident they were involved in," Greene said. "The only thing worse than all these guys getting killed is not to have us learn anything from it."
CAIC report: http://bit.ly/Zs5JAv
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