RUNIT DOME, MARSHALL ISLANDS — The U.S. Congress is demanding an investigation into the Runit Dome in the Marshall Islands, which contains radioactive waste and is being threatened by rising sea levels.
The dome was built in the late 1970s during the Cold War era.
It was originally built to contain radioactive waste from nuclear tests conducted by the U.S on the islands, according to CBS News.
The U.S. conducted 64 nuclear weapons tests at Bikini and Enewetak atolls between 1946 to 1958.
The tests included the "Bravo" hydrogen bomb, which was said to be 1,000 times more powerful than the atomic bomb the U.S. dropped on Hiroshima, Al Jazeera reports.
According to the Los Angeles Times, the site holds more than 3.1 million cubic feet of radioactive ash and soil from the nuclear explosions, which was closed with a concrete dome that is 18 inches thick.
This was originally meant to be a temporary solution since the bottom of the crater was never lined.
As part of the National Defense Authorization Act, the Department of Energy must investigate the deteriorating concrete site and submit a report about the risks the dome poses to the people, wildlife, and surrounding environment by June 2020, the Los Angeles Times reports.
The report must also assess how rising sea levels could affect the nuclear dome.
In May 2019, UN Secretary General Antonio Guterres had raised concerns about the risk of the dome's radioactive material leaking into the sea, reports BBC News.
According to the U.S. Department of Interior, the Marshall Islands was a UN trust territory that was administered by the U.S. from 1947 to 1978.
It became a sovereign nation in 1979.