The roof of a tunnel "caved in" at the Hanford nuclear site in Washington Tuesday morning, per Hanford spokesman Destry Henderson. Hundreds of workers were in the "take cover" position after the collapse, and facility personnel were evacuated, according to the Energy Department, which labeled the incident an emergency.
What happened: The tunnel that caved in was filled with radioactive trains that transported nuclear waste. A spokesperson for the Washington Department of Ecology said that there has been no detection of a radiation release, which Henderson confirmed Tuesday afternoon.
Why it matters: The Energy Department has acknowledged in 20 studies that there is a safety risk to the workers at Hanford; the site is where plutonium was produced for the Nagasaki Bomb and has been dubbed "the most toxic place in America" and "an underground Chernobyl waiting to happen" since it's the largest depository of radioactive defense waste.