An emergency was just declared in Hanford, Washington after a tunnel packed full of train cars containing radioactive waste collapsed Tuesday morning. Hundreds of workers were told to “take cover” and local residents warned to stay indoors for fear that nuclear contamination could spread. Hanford, which sits 200 miles north-east of Seattle, is considered the most contaminated nuclear site in the US.

The tunnel at Hanford contained rail cars used to carry the spent fuel to a processing facility. The collapse occurred in the center of the site in what is being called a very “high hazard operation.”

According to the Energy Department, the collapse could result in radioactive materials making their way into nearby soil or water. “There are concerns about subsidence in the soil covering railroad tunnels near a former chemical processing facility. The tunnels contain contaminated materials.”

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An unnamed sourced says that the collapse could have been caused by vibration from work being done at the site. Hanford has been in the process of being cleaned up for nearly three decades. Originally, the site was used to produce plutonium for defense and commercial reactors, but those operations ended in 1980.

Via The Washington Post

images via Wikimedia and Flickr