Russia/Ukraine/ex-USSR
The former Soviet Union was rocked by one of the world's worst environmental disasters on April 26, 1986, when Unit 4 at the Chernobyl reactor site exploded, sending a radioactive plume across the world. The former Soviet Union is still also the site of some of the world's worst radioactive contamination from its nuclear weapons program.
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Daily Mail - Inside the new £1.3 billion 354ft tall structure that protects the world from Chernobyl's radiation more than 30 years after Reactor No. 4 exploded - By Chris Dyer For Mailonline and Associated Press
July 9, 2019