Workers at the Hanford Nuclear Reservation were evacuated Tuesday morning after a portion of a tunnel that contained nuclear waste collapsed, reports the Associated Press.
No workers were in the tunnel at the time of the collapse. A Department of Energy spokesperson said there has been no release of radiation and no workers were injured.
The Hanford site is America's largest toxic waste dump and has been the subject of discussion concerning the clean up of nuclear waste for years.
Hanford was previously used to manufacture plutonium for nuclear weapons.
The Hanford site is located near Richland, Washington and is approximately half the size of Rhode Island.