LINDA WERTHEIMER, HOST:
It's day six of the search and rescue operation at the site of the landslide in Oso, Washington. The death toll stands right now at 26. Ninety people are still reported missing. That's left many families in limbo waiting for news. NPR's Martin Kaste reports on why the recovery work has been so excruciatingly slow.
MARTIN KASTE, BYLINE: One big reason is the muck. This landslide fell into a river. It's spring and it's still raining. Steve Mason is a fire battalion chief, and he's with the state's incident management team. He points out the struggling heavy machinery.
STEVE MASON: There's so much water out here that the excavators to get out here need to build themselves - basically take trees and lay down and build themselves a ramp to get out to certain areas. We also have a plywood path out here so that the workers can get out here and back to port faster.
KASTE: And then there is the debris itself. This landslide didn't just push the houses around. As one national guardsman put it, it's as if the houses were put in a blender with trees and mud. Now workers are trying to sift through that.
MASON: Those piles are people's residences, and they are, like I said, very methodically going through those residences one by one.
KASTE: And that's what searchers call this whole site: The Pile. John Norman understands this. He was the New York Fire Department's manager of search and rescue at Ground Zero. That was also nicknamed The Pile.
JOHN NORMAN: It's never the same. Every action that you take has another reaction somewhere down the line. So it's a very, very fluid environment that the rescuers have to be very aware of what has changed from moment to moment. Particularly in that case with the river flowing right nearby, that's a very, very difficult scene.
KASTE: Attacking this kind of pile means balancing heavy demolition on one side with care for the buried victims on the other. The last thing you want, Norman says, is to have a backhoe damage a body. To avoid that kind of scenario in Oso, they're using dogs. But even a dog's super-sensitive nose won't always lead you directly to a buried victim.
TRAVIS HOTS: Most of the time that scent takes a path of least resistance, and so that scent might come up 30, 40, 50 feet away.
KASTE: The fire chief, Travis Hots says when the dogs alert, that's just the beginning of an elaborate process.
HOTS: They'll probe the whole area, and then the handler watches the reaction of the dogs. And if the dog starts to get really excited, then they'll start working that area even more with the probes. And then they'll bring another dog in, and if that second dog comes in and confirms that, then that's a point that we pinpoint, and we start using our hands to move things.
KASTE: In short, it's a painstaking process, even more so when you work with the assumption that there may still be survivors in there. John Norman says it's hard to abandon hope of finding survivors, and it's hard to make the transition to a pure recovery operation.
NORMAN: I was part of the decision-making process in New York City. It's a very, very difficult decision. It has to be made with a complete evaluation of the circumstances, the type of debris that the victim might be trapped in. Are there any void spaces that might be allowing them to survive? And that's the toughest choice the incident commander will ever make.
KASTE: Officials in Oso still say they're operating in rescue mode, but they are confronting an estimated 15 million cubic yards of mud and debris, and some of it is covering an important local highway. They know that at some point soon, that difficult decision will have to be made. Martin Kaste, NPR News.
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