Mayak
The Mayak Production Association (Russian: Производственное объединение «Маяк», from Маяк 'lighthouse') is one of the biggest nuclear facilities in the Russian Federation, housing plutonium production reactors and a reprocessing plant. The nuclear complex is located 150 km south-east of Ekaterinburg, between the towns of Kasli and Tatysh, and 72 km northwest of Chelyabinsk. The closest city, Ozyorsk, is the central administrative territorial district. As part of the Russian (formerly Soviet) nuclear weapons program, Mayak was formerly known as Chelyabinsk-40 and later as Chelyabinsk-65, referring to the postal codes of the site.
In 1957 Mayak was the site of the Kyshtym disaster, one of the worst nuclear accidents in history. During this catastrophe, a poorly maintained storage tank exploded, releasing 50-100 tons of high-level radioactive waste. The resulting radioactive cloud contaminated an expansive territory of more than 750 km2 (290 sq mi) in the eastern Urals with the consequence of sickness and death from radiation poisoning.
The Soviet regime kept this accident secret for about thirty years. The event was eventually rated at 6 on the seven-level INES scale, third in severity only to the disasters at Chernobyl in Ukraine and Fukushima in Japan.
Mayak's nuclear facility plant covers about 90 square kilometers. The site borders Ozyorsk, in which a majority of the staff of Mayak live. Mayak, itself, was not shown on Soviet public maps. The location of the site together with the plant city was chosen to minimize the effects that harmful emissions could potentially have on populated areas. Mayak is surrounded by a ~250 km2 exclusion zone. Nearby is the site of the South Urals nuclear power plant.
The Mayak plant was built between 1945–48, in a great hurry and in total secrecy as part of the Soviet Union's atomic bomb project. Five nuclear reactors were built to make, refine, and machine plutonium for weapons. Later the plant came to specialize in reprocessing spent nuclear fuel from nuclear reactors and plutonium from decommissioned weapons. Today the plant makes tritium and radioisotopes, not plutonium. In recent years, proposals that the plant reprocess waste from foreign nuclear reactors have given rise to controversy.
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