The U.S. Department of Energy (DOE) said that officials are responding to reports of a cave-in of a 20-foot section of a tunnel that is hundreds of feet long that is used to store contaminated materials at the Hanford nuclear waste site in eastern Washington State.

The tunnel is located next to the Plutonium Uranium Extraction Facility, also known as PUREX, which is located in the center of the Hanford Site in an area known as the 200 East Area. Initial reports said there is no indication of a release of contamination.

Image of the cave-in, visible at top of photoImage of the cave-in, visible at top of photoCrews deployed a TALON, a remote operated surveying device that is capable of radiological and industrial hygiene monitoring as well as capturing video footage. The TALON device allows crews to safely survey potential areas of contamination from a distance of up to ½ mile.

All personnel in the vicinity of the PUREX facility have been accounted for and there are no reports of injuries.

The cave-in was discovered during a routine surveillance of the area by workers. The tunnels are hundreds of feet long, with approximately eight feet of soil covering them. The depth of the subsidence of soil appears to be into the tunnel.

The tunnels were used beginning in the 1950s to store contaminated equipment. The cave-in is in an area where the two tunnels join together.

An alert was declared at the Hanford Site at approximately 8:30 AM on May 9. An alert is the lowest level of emergency classification and is declared when an event is not expected to affect personnel outside of the facility boundary. Later in the morning, the alert was expanded to a Site Area Emergency. A Site Area Emergency is declared when the event is affecting or could potentially affect personnel beyond the facility boundary but not beyond the boundary of the Hanford Site.

For more than 40 years, reactors located at Hanford produced plutonium for America’s defense program. Crews responsible for site cleanup are dealing with several different kinds of waste in a number of different forms, with many of the wastes being potentially harmful to people and the environment.