Chelyabinsk Oblast has been associated with top-secret nuclear research since the 1940s . While there are no nuclear power stations in Chelyabinsk , a number of production reactors were located there starting with the early Cold War . A serious nuclear accident occurred in 1957 at the Mayak nuclear fuel reprocessing plant , 150 km north-west of the city , which led to evacuations and fatalities throughout the oblast , although not in Chelyabinsk city . The province was closed to all foreigners until 1992 , with the sole exception of allowing a British medical team in following a two-train rail explosion in the mid-1980s
serious nuclear accident
Kyshtym disaster
Chelyabinsk Oblast