A large and complicated nuclear legacy has been left behind by the break up of the Soviet Union with numerous nuclear facilities located in Russia and other former Soviet states. Although civilian activities have contributed to this legacy, the majority of contamination issues in the former Soviet Union were created by military nuclear facilities used for the production of nuclear weap­ons. This problem was exacerbated by a previously relaxed attitude towards environmental issues with regards to nuclear waste disposal. Three nuclear facilities, Chelyabinsk-65, Tomsk-7, and Krasnoyarsk-26 operated in secret in the Ural mountains during the Cold War and were not subject to strict environmental practices.16 Of these sites, Chelyabinsk-65 (Mayak) is the most publicised regarding its former activities, revealing a long history of accidental release and discharges, contributing to significant environmental contamina­tion which will be discussed in greater detail below.

The worst nuclear power plant accident in history, the only level 7 event on the International Nuclear Event Scale to have occurred, happened on the 26th of April 1986 at Chernobyl, when a test was carried out to determine the ability of a turbine generator to provide power in the event of a station blackout. Serious violations of safety procedures and operating rules resulted in a steam explosion, cutting cooling channels on both sides of the reactor core resulting in a further explosion.17 The release of 137Cs from the explosion is estimated to have been around 85 PBq with an estimated 1760 PBq of 131I, 10 PBq of 90Sr and 3 PBq of plutonium isotopes also released.18,19