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. Last Updated: 07/27/2016

Hundreds Remember Chelyabinsk Nuclear Blast

Several hundred people gathered in Chelyabinsk over the weekend to commemorate the 50th anniversary of a catastrophic explosion at a nuclear dump site and to call for an end to waste processing at what was once a major Soviet atomic weapons facility, Greenpeace Russia said.

On Sept. 29, 1957, a waste tank at the Mayak nuclear weapons plant in the closed Ural Mountains city of Chelyabinsk-65 exploded, contaminating 23,000 square kilometers and prompting authorities to evacuate 10,000 residents from neighboring regions.

Some details of the disaster were first released to the public in 1989 as part of Soviet leader Mikhail Gorbachev's liberalization drive, but its impact on the local population remains largely unknown even now. Environmental activists say the damage has been compounded by other accidents, leaks and the planned discharge of liquid waste.

Mayak is now the country's main nuclear waste processing plant, and Greenpeace Russia said activists called for a halt to those operations during a demonstration Saturday in the nearest major city, Chelyabinsk.

As after the explosion and fire at Chernobyl in Ukraine, young men including soldiers and students were sent to clean up after the explosion at Mayak, exposing them to radiation many believe caused health problems later. Greenpeace Russia said tumor rates among a few hundred people in two villages at the edge of the area that was evacuated are five times higher than the norm.