An expanded report on a deadly avalanche near Whittier last week sheds new light on the final moments of the Anchorage snowmachiner who was fatally buried in the slide.

The Chugach National Forest Avalanche Information Center issued its final report on the May 2 avalanche on the upper Blackstone Glacier which killed 41-year-old Chad Christman. Preliminary accounts of the slide estimated it as 2 to 4 feet deep, 300 feet wide and powerful enough to destroy a small building.

Anchorage snowmachiner Chad Christman, 41, was killed in a Blackstone Glacier avalanche on Wednesday, May 2, 2018. (Credit: Stefanie Suydam)

The expanded version, based on extensive interviews with survivors from the snowmachining party, gives a closer account of the incident and the factors which led up to it.

According to the report, a group of six snowmachiners left the Whittier trailhead at about 10:15 a.m. on the day of the slide, planning to meet up with four other riders about an hour behind them on the glacier “for a day of sunshine and spring riding to end the season.”

“All members of both parties were advanced riders and all were familiar with the area,” avalanche forecasters wrote. “Everyone in the original group of six carried avalanche transceivers and most carried shovels and probes. Two people in that group had avalanche airbags.”

The groups met up on the glacier early that afternoon, when two people from the six-rider group began traveling back to the trailhead at about 3:30 p.m. One of the remaining four riders saw the avalanche catch the other three, beginning about 200 feet above where Christman and the others were cresting a sub-ridge and descending into a gully.

The rider who saw the slide reported seeing Christman and one of the other snowmachiners “disappearing and reappearing in the moving debris.” The avalanche left all three snowmachines largely or fully buried.

One of the two survivors was struck from behind, but inflated his avalanche backpack and emerged 50 feet from his snowmachine with only his legs buried. The other survivor was spun through a full circle by the slide and hit the gas, but couldn’t escape the wave of descending debris.

“He described the next several seconds as diving under the snow then resurfacing before diving again,” forecasters wrote. “[He] never separated from his snowmachine and came to rest near the toe of the debris still clutching his machine and buried up to his armpits/neck with one hand free.”

Christman was fully buried in the slide near his snowmachine, with only one hand still visible. The survivor still on his snowmachine was the first person able to act.

“[He] was able to extract himself in less than a minute and scanning the debris, he saw [the airbag rider] on the surface and what he recognized as [Christman’s] glove breaking the surface and still moving,” forecasters wrote. “[He] was the first to make contact with [Christman’s] moving hand and began digging toward where he thought his face was.”

Snowmachiner Chad Christman's sled, buried by the May 2, 2018 avalanche that killed him on Blackstone Glacier. (Credit: From CNFAIC)

The rider was able to clear Christman’s airway within three minutes of the burial, with the rest of the foursome arriving to dig him out and begin conducting CPR within five minutes. The man who initially responded to Christman found the two snowmachiners who had started to leave, and they used their cellphones to call for help.

More snowmachiners arrived to provide aid about half an hour after the avalanche, with an Alaska Air National Guard helicopter arriving to pick up Christman afterward.

“CPR was continued as [Christman] was transported onto the helicopter and flown to Providence Alaska Medical Center in Anchorage,” forecasters wrote. “[Christman] was declared deceased upon arrival at the hospital.”

The Prince William Sound region had received nearly 11 inches of rain in four spikes of precipitation amid stormy weather between April 18 and April 29, which forecasters said “can equate to well over 100 inches of snowfall” at the roughly 5,000-foot elevation of the avalanche. Snow had stopped and skies had cleared in the two days preceding the fatal slide.

As a result, the center concluded that the slide likely involved about 2 feet of snow from the later days of the storm.

The area where the avalanche occurred isn’t covered by forecasts from the avalanche center, which shuttered its operations for the season at the end of April but has warned of late-season avalanche dangers in the region's backcountry.

The center concluded its report by thanking the snowmachiners who spoke with staff about Christman’s death.

A GoFundMe account set up for Christman's family has raised nearly $8,500.

Copyright 2018 KTVA. All rights reserved.

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