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Kyshtym disaster

Coordinates: 55°43′N 60°49′E / 55.717°N 60.817°E / 55.717; 60.817
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Map of the East Urals Radioactive Trace (EURT): area contaminated by the Kyshtym disaster.

The Kyshtym disaster was a radiation contamination incident that occurred on 29 September 1957 at Mayak, a nuclear fuel reprocessing plant in Russia (then a part of the Soviet Union). It measured as a Level 6 disaster on the International Nuclear Event Scale, making it the second most serious nuclear accident ever recorded (after the Chernobyl disaster). The event occurred in the town of Ozyorsk, a closed city built around the Mayak plant. Since Ozyorsk/Mayak (also known as Chelyabinsk-40 and Chelyabinsk-65) was not marked on maps, the disaster was named after Kyshtym, the nearest known town.

Background

After the Second World War the Soviet Union lagged behind the United States in development of nuclear weapons, so it started a rapid research and development program to produce a sufficient amount of weapons-grade uranium and plutonium. The Mayak plant was built in a great hurry between 1945 and 1948. Gaps in Soviet physicist's knowledge about nuclear physics at the time made it difficult to judge the safety of many decisions. Also, environmental concerns were not taken seriously during the early development stage. Initially Mayak was dumping high-level radioactive waste into a nearby river, which was taking waste to the river Ob, flowing farther down to the Arctic Ocean. Later on, Lake Karachay was used for open-air storage.[1]

A storage facility for liquid nuclear waste was added around 1953. It consisted of steel tanks mounted in a concrete base, 8.2 meters underground. Because of the high level of radioactivity, the waste was heating itself through decay heat (though a chain reaction was not possible). For that reason, a cooler was built around each bank containing 20 tanks. Facilities for monitoring operation of the coolers and the content of the tanks were not adequate.[2]

Explosion

In September 1957 the cooling system in one of the tanks containing about 70–80 tons of radioactive waste failed, and the temperature in it started to rise, resulting in a non-nuclear explosion[citation needed] of the dried waste having a force estimated at about 70–100 tons of TNT, which threw the concrete lid, weighing 160 tons, into the air.[2] There were no immediate casualties as a result of the explosion, which released an estimated 2 to 50 MCi (74 to 1850 PBq ) of radioactivity.[1][3][4]

In the next 10 to 11 hours the radioactive cloud moved towards the northeast, reaching 300–350 kilometers from the accident. The fallout of the cloud resulted in a long-term contamination of an area of more than 800 square kilometers, primarily with caesium-137 and strontium-90.[1] This area is usually referred to as the East-Ural Radioactive Trace (EURT).[5]

Aftermath

Because of the secrecy surrounding Mayak, the population of affected areas were not initially informed of the accident. A week later (on 6 October) an operation for evacuating 10,000 people from the affected area started, still without giving an explanation of the reasons for evacuation. People "grew hysterical with fear with the incidence of unknown 'mysterious' diseases breaking out. Victims were seen with skin 'sloughing off' their faces, hands and other exposed parts of their bodies."[6] It was Zhores Medvedev who revealed the nature and extent of the disaster to the world.[7]

Even though the Soviet government suppressed information about the figures, it is estimated that the direct exposure to radiation caused at least 200 cases of death from cancer.[8]

To reduce the spread of radioactive contamination after the accident, contaminated soil was excavated and stockpiled in fenced enclosures that were called "graveyards of the earth".[9]

The Soviet government in 1968 disguised the EURT area by creating the East-Ural Nature Reserve, which prohibited any unauthorised access to the affected area.

Rumours of a nuclear mishap somewhere in the vicinity of Chelyabinsk had long been circulating in the West. That there had been a serious nuclear accident east of the Urals was eventually inferred from research on the effects of radioactivity on plants, animals, and ecosystems, published by Professor Leo Tumerman, former head of the Biophysics Laboratory at the Institute of Molecular Biology in Moscow, and associates.

According to Gyorgy,[10] who invoked the Freedom of Information Act to gain access to the relevant Central Intelligence Agency (CIA) files, the CIA knew of the 1957 Mayak accident all along, but kept it secret to prevent adverse consequences for the fledgling American nuclear industry. Only in 1990 did the Soviet government declassify documents pertaining to the disaster.[11]

Current situation

The level of radiation in Ozyorsk itself is claimed to be safe for humans, but the area of EURT is still heavily contaminated with radioactivity.[8]

References

  1. ^ a b c "Chelyabinsk-65".
  2. ^ a b "Conclusions of government commission" (in Russian).
  3. ^ Kabakchi, S. A. (1995). "Data Analysis and Physicochemical Modeling of the Radiation Accident in the Southern Urals in 1957". Moscow ATOMNAYA ENERGIYA (1): 46–50. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  4. ^ See also List of military nuclear accidents
  5. ^ Dicus, Greta Joy (January 16, 1997). "JOINT AMERICAN-RUSSIAN RADIATION HEALTH EFFECTS RESEARCH". United States Nuclear Regulatory Commission. Retrieved 30 September 2010.
  6. ^ Pollock, Richard (1978). "Soviets Experience Nuclear Accident". Critical Mass Journal.
  7. ^ Medvedev, Zhores A. Nuclear disaster in the Urals translated by George Saunders. 1st Vintage Books ed. New York : Vintage Books, 1980, c1979, ISBN 0394744454.
  8. ^ a b "The Southern Urals radiation studies. A reappraisal of the current status". Journal Radiation and Environmental Biophysics. 41. 2002. {{cite journal}}: horizontal tab character in |journal= at position 8 (help)
  9. ^ John R. Trabalka (1979), "Russian Experience," pages 3-8 in Environmental Decontamination: Proceedings of the Workshop, December 4–5, 1979, Oak Ridge, Tennessee, Oak Ridge National Laboratory, CONF-791234
  10. ^ Gyorgy, A. (1979). No Nukes: Everyone's Guide to Nuclear Power. ISBN 0919618952.
  11. ^ "The decision of Nikipelov Commission" (in Russian).

55°43′N 60°49′E / 55.717°N 60.817°E / 55.717; 60.817

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