A huge dome-like structure built by the United States 40 years ago in the Marshall Islands to contain the deadly radioactive debris resulting from more than a decade of nuclear tests conducted in the South Pacific in the 1940s and 50s has become dangerously vulnerable, The Washington Post reported on Monday.
Due to disrepair and rising sea tides, experts fear a strong storm could breach the dome and release the nuclear debris.
UN Secretary General António Guterres, who toured the South Pacific last week, said “I’ve just been with the president of the Marshall Islands, who is very worried because there is a risk of leaking of radioactive materials,” Agence France-Presse reported.
The Americans began building the dome in the 1970s as a belated response to the nuclear testing, transporting tainted surface soil across the islands to a 328-foot crater remaining from a 1958 test explosion. The U.S. military dumped the material into the crater in 1980 and constructed an 18-inch-thick concrete dome to seal it off.
However, the project was only supposed to be temporary until a more permanent site was developed, which never happen, according to The Guardian.
The Australian Broadcasting Corporation reported that among the fallout material contained in the dome is plutonium-239, an isotope that is one of the world’s most toxic substances.
Cracks have reportedly started to appear in the dome, which was never properly lined and could mean that rising seawater could breach the structural integrity.
A Marshallese official told The Guardian the problem is exacerbated, because “the local government will neither have the expertise or funds to fix the problem if it needs a particular fix.”
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