Park rangers and rescuers often are able to retrieve bodies within days of an accident, but sometimes it takes weeks or months, when conditions have improved and snow has melted on parts of the mountain.
Occasionally victims are never found, as in the case of 11 people swept to their deaths in an ice fall in 1981 in Mount Rainier's deadliest accident. The same is true of a non-alpine accident in which a cargo transport plane crashed into the mountain in 1946 — the bodies of 32 Marines remain entombed.
"The mountain is so inaccessible and can be inhospitable. We can't always retrieve everybody who is lost there, unfortunately," said Patti Wold, a spokeswoman with Mount Rainier National Park.
The bodies of the two guides and four climbers who fell to their deaths last week on the 14,410-foot glaciated peak may never be recovered because of the hazardous terrain, authorities say.
"The degree of risk in that area, due to the rock fall and ice fall that's continuously coming down from that cliff onto the area where the fall ended, we cannot put anybody on the ground," Wold said.
It's unclear whether the climbers were moving or camping at the time of the accident, Wold said this past weekend. Searchers located camping and climbing gear and detected signals from avalanche beacons buried in the snow at the top of the Carbon Glacier at 9,500 feet in elevation.
It's also not known what caused the climbers to fall from their last known whereabouts at 12,800 feet on Liberty Ridge, whether it was rock fall or an avalanche. They were last heard from at 6 p.m. Wednesday when the guides checked in with their Seattle-based company, Alpine Ascents International, by satellite phone. The group failed to return Friday as planned.
Alpine Ascents identified the two guides on its website. Matthew Hegeman, the lead guide, was described as intense, philosophical and always in the pursuit of excellence with a good sense of humor. Eitan Green, the other guide, loved his time in the mountains and was a strong leader and quick to smile, the website said.
The Seattle Times reported Monday that Seattle mountain climber John Mullally was one of the six who died. His wife, Holly Mullally, issued a statement Monday saying that she had previously been on climbs organized by the company, and had also climbed with Hegeman.
"I respected his leadership and found him to be experienced, skilled, appropriately conservative, thoughtful, and someone who I could count on to keep my husband safe, barring tragedy beyond our control," Holly Mullally wrote of Hegeman.
Officials at Maine's Colby College said Green was a 2009 graduate of the college. Colby spokesman Steve Collins said the Massachusetts native majored in anthropology and was a member of the college mountaineering club. A memorial service is scheduled for June 5 in Levine Chapel in Brookline, Massachusetts.
Rob Mahaney told The Associated Press that his 26-year-old nephew, Mark Mahaney, of St. Paul, Minnesota, was among those presumed dead. He said the climber's father and brother flew to Seattle on Saturday after learning what happened. Mahaney said his nephew had climbed Rainier before.
The area will be checked periodically by air in the coming weeks and months, Wold said. They will also evaluate the potential for a helicopter-based recovery as snow melts and conditions change.
In 2012, park rangers recovered the bodies of three climbers about eight months after they disappeared during unrelenting storms on Mount Rainier.
In 2001, the body of a 27-year-old doctor was discovered more than two years after he vanished while snowboarding on the mountain. Also that year, the remains of three men were removed from the mountain after being entombed there for nearly 30 years after their small plane crashed. A hiker and former climbing ranger found the wreckage of the single-engine aircraft that crashed in January 1972.
La Corte reported from Olympia, Washington. Associated Press writer Dinesh Ramde in Milwaukee contributed to this report.
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