MYNORTHWEST NEWS

Environmental disaster averted in Oso mudslide

Apr 1, 2014, 3:21 PM | Updated: 4:55 pm

Along with the human toll, the Oso mudslide had the potential to cause significant environmental damage to the Stillaguamish River. But experts say it looks like the long-term potential for contamination of the pristine waters and surrounding areas is minimal.

Spill responders from the Washington state Department of Ecology have been monitoring the slide area and downstream since the estimated 10 million tons of soil came down Saturday, March 22nd.

The destruction of dozens of houses created a toxic mix of household chemicals, gasoline, diesel, heating oil and other chemicals, along with human waste from septic tanks. Crews in the area are undergoing decontamination after working in the sludge.

Crews are finding a variety of tanks and containers in the debris, with far more buried in the mud. But spill responder Dick Walker says they don’t expect the toxic chemicals to spread beyond the slide zone.

“We don’t know about some of these heating oil tanks. Deisel can travel through the soil and depending on where they ended up we’re going to have to keep an eye on it to see if diesel starts emerging,” Walker says. Luckily, no fuel spilled into the river following the slide.

Because the operation remains focused on recovering victims, crews have yet to begin cleaning up. Once they can start that process, they’ll focus on removing as much potentially toxic debris as possible.

“For some of the smaller containers, much of that is buried simply too deeply to ever dig after that. You know some of the site is covered with 70 feet of earth,” Walker says.

Walker says while the debris poses a health risk to responders, any potential biological contamination should subside over time.

The biggest impact could be from silt that flowed into the river following the slide. Walker says that could damage fisheries downstream, and FEMA and the EPA will be monitoring.

“This is not primarily an environmental story. This is really a story about the tragedy and the community coming together,” he says. “But we’ll continue to monitor this area for a long time.”

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