They were analyzing conditions, digging snowpits and doing everything by the book when the avalanche broke loose above Silverton, Ryan Moomey said Thursday.

Moomey was skiing with Olivia Buchanan on Tuesday afternoon when Buchanan triggered a slide on a gully called Rabbit Ears at about 11,000 feet elevation. The slide carried Buchanan several hundred feet down the mountain, and she was unresponsive and not breathing by the time Moomey reached her.

Buchanan, 23, a 2010 Durango High School graduate who was studying snow science at Montana State University, was evacuated by rescue crews to Silverton on Tuesday evening and taken via helicopter to Mercy Regional Medical Center. Staff there could not revive her, and she was pronounced dead that evening.

“She was just so smart about everything she did all day,” said Moomey, who has been getting counseling from others who’ve been through similar circumstances, as well as family and friends. Many advised him to share his experiences and talk things out.

“She took every protocol you’re supposed to do. I was very confident being up there with her,” Moomey said.

Buchanan’s death comes less than two years after avalanches a month apart killed Durango natives Peter Carver and Joe Philpott. Carver was 23 when he died Feb. 2, 2013, north of Silverton. Philpott was 26 when he died March 2, 2013, near Cameron Pass west of Fort Collins.

Avalanche conditions were classified as “moderate” when Moomey and Buchanan went out Tuesday. But moderate does not mean “completely safe,” something the two were well aware of.

Brian Lazar, deputy director of the Boulder-based Colorado Avalanche Information Center, said “moderate” means that spontaneous, or natural, slides are not expected.

“But on some of those suspect slopes it’s not necessarily likely but it’s certainly possible for a person to trigger a large and destructive avalanche,” Lazar said. Right now in the San Juans, suspect slopes include those facing west through north to east on slopes near and above treeline.

Lazar visited the slide area Wednesday with Silverton-based forecasters Susan Hale and Mark Gober. Lazar said in a phone interview Thursday that the major problem right now with the snowpack, and this is not uncommon for the Rocky Mountains, is a persistent slab – a cohesive snow layer sitting on top of weaker snow.

“Unfortunately that weaker snow sticks around for a while,” Lazar said.

Moomey, a 2006 DHS grad, met Buchanan this winter at a ski-rental shop at Purgatory at Durango Mountain Resort, where they both were working. They’d skied together at Purgatory and ventured into the backcountry.

On Tuesday they climbed most of the way up Kendall Mountain from Silverton, then headed down. They’d considered Idaho Gulch, but Rabbit Ears led more directly to where he’d parked, Moomey said.

They took turns skiing, stopping and watching each other. Moomey remembers Buchanan turning to him on Rabbit Ears and saying, “It’s my turn. Watch me.”

“Within the blink of an eye the snow just let go, and then she went down,” Moomey said.

After the slide stopped, he switched his avalanche beacon to receive and skied as best he could down a dirty and rocky slope nearly shorn of snow. The avalanche forecasters Wednesday measured the slide as 2 to 4 feet deep and about 150 feet wide; it started on an average 40- degree slope.

It took a couple of minutes, but finally Moomey found her in a grove of trees, her torso wrapped around a tree trunk and her head slightly buried.

Moomey pulled her off the tree, took off her helmet and backpack and tried to get her airway open. She was not breathing, and he called 911 immediately.

He continued with CPR for about an hour before four members of San Juan Search and Rescue arrived.

“I felt so alone,” Moomey said. “I could see the town, and I could see everybody (mobilizing for the rescue), but I was just up there by myself with her. ... I was so scared for her.”

Search and Rescue took Buchanan down the mountain in the growing darkness.

Moomey has been skiing the backcountry for a decade, has attended an avalanche school and has continued to study avalanche reports and conditions. Buchanan interned with the Silverton Avalanche School in 2011.

Both were wearing helmets and had beacons, shovels, probes, first-aid kits and extra gear, Moomey said.

“We were having fun,” Moomey said. “Great weather. Blue skies. We were laughing and joking.

“She took every precaution, every protocol, everything we were supposed to do. In the blink of an eye, it just happened. A total accident. ... There’s no blame on anybody. We both knew the risks involved in the sport we both loved doing.”

Jay Welz, field operations manager for the Silverton-based Center for Snow and Avalanche Studies, said that Buchanan took a course he was assistant teaching while finishing his master’s degree at Montana State.

“She was really engaged and eager to learn; she already knew quite a bit,” Welz said. “It’s very sad.”

Lazar, with the Avalanche Information Center, offered condolences to Buchanan’s family and friends. He encouraged backcountry users to avoid slopes that seem at all questionable.

“Have fun recreating on all the other types of terrain available. ... There’s plenty of other options available,” he said. “This was a fairly committing steep terrain feature with serious consequences should something even small go wrong. And unfortunately that’s what happened.”

johnp@durangoherald.com. Freelance writer Samantha Wright contributed to this report.

Backcountry information

The Colorado Avalanche Information Center this season discontinued its phone hotline forecasts but has them online, with maps and other explanatory information about conditions.

Colorado Avalanche Information Center: http://avalanche.state.co.us.

South San Juan backcountry forecast: http://avalanche.state.co.us/forecasts/backcountry-avalanche/south-san-juan.

Accident reports: http://avalanche.state.co.us/accidents/colorado.

Other sites

Those interested in a more in-depth online study can check out two free informational websites:

Backcountry Starts Here (http://backcountrystartshere.com) is targeted to the 18-26 age group and talks about gear, training, forecasts and the big picture.

Business of the Backcountry 2.0 (http://bit.ly/bizofthebackcountry), sponsored by Durango-based Verde Brand Communications, was developed for retailers and sales reps but is open to anyone interested. It features interviews and seminars with experts in the backcountry.