The Hanford nuclear site in Washington state — one of the largest and most contaminated storehouses of radioactive waste in the US — is currently undergoing an emergency.
The US Department of Energy oversees Hanford. It's a Cold War-era facility that led US production of plutonium for use in tens of thousands of nuclear weapons.
The site no longer produces plutonium. However, millions of gallons' worth of radioactive waste is still stored there, and workers are carrying out a lengthy process of decommissioning the nuclear reservation — The Seattle Times dubbed it "the nation's most contaminated nuclear site" in 2007.