Nuclear fission was a sensitive subject in the Soviet Union during the Cold War years – to the point where Russia’s Mayak nuclear fuel reprocessing plant and the closed town of Ozyorsk that was built around it in the Ural Mountains didn’t even feature on maps. But they existed all right, even though the nuclear catastrophe that occurred there in 1957 had to be named after the nearest ‘official’ town, Kyshtym.
After World War II, the Soviet Union lagged behind the USA in the vital arena of nuclear technology and scrambled to catch up with a little help from information gathered by its spies in the West But the need for weapons-grade uranium and plutonium led to bad decision-making when it came to building and operating nuclear plants. Nowhere was this more evident than at Mayak, where ignorance about proper safety procedures was coupled with gross environmental negligence – highly toxic radioactive waste initially being dumped straight into the nearby river.
In 1953, in an effort to curb the radioactive pollution, 40 underground storage tanks for liquid waste were constructed. The self-generated heat from this radioactive waste rose to a dangerously high temperature, so cooling units were added. But neither these nor the tanks themselves were adequately monitored.
When one of the cooling systems failed in September 1957, the temperature in one bank of tanks rose rapidly and the waste within exploded. There were no immediate casualties, but a radioactive cloud swiftly spread to the northeast, severely contaminating an area of 800 sq km (310 sq mi). The authorities belatedly reacted a week later, evacuating some 10,000 people from the affected zone – but without telling them why. Many became hysterical when symptoms such as radiation burns and peeling skin occurred. The truth only came out when the USSR collapsed in 1990.
When: September 29 1957
Where: South Ural Mountains, Russia
Death toll: At least 200 people died of radiation sickness and it is estimated that several hundred more died from radiation-related cancers. Over a period of 45 years more than 500,000 people were exposed to radiation, many of them at levels 20 times greater than the victims of Chernobyl.
You should know: Although rumors of a nuclear accident in Russia circulated in the West for years, the Soviet cover-up was so effective that the Kyshtym disaster was only officially admitted in 1990. America’s Central Intelligence Agency knew all about it almost as soon as the accident happened, but kept the information quiet to avoid raising public concern about the USA’s own nuclear industry.