Kyshtym disaster
Encyclopedia
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 third most serious nuclear accident ever recorded (after the Chernobyl disaster
, and Fukushima Daiichi nuclear disaster
, both Level 7 on the INES scale). 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.
, the Soviet Union
lagged behind the United States
in development of nuclear weapon
s, 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 physicists' 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. All six reactors were on Lake Kyzyltash and used an open cycle cooling system, discharging irradiated water directly back into the lake. Initially Mayak was dumping high-level radioactive waste into a nearby river, which was taking waste to the river Ob
, flowing further down to the Arctic Ocean
. Later on, Lake Karachay
was used for open-air storage.
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.
s (see ammonium nitrate bomb
). The explosion, estimated to have a force of about 70–100 tons of TNT threw the concrete lid, weighing 160 tons, into the air. 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.
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
. This area is usually referred to as the East-Ural Radioactive Trace (EURT).
Although vague reports of a "catastrophic accident" began appearing in the western press in April 1958, it was only in 1976 that Zhores Medvedev
made the nature and extent of the disaster known to the world.
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.
"In 1992, a study conducted by the Institute of Biophysics at the former Soviet Health Ministry in Chelyabinsk found that 8,015 people had died within the preceding 32 years as a result of the accident."
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".
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 demonstrated by Zhores Medvedev, who, after his reference to the disaster in a western publication was derided by western nuclear industry sources, showed that numerous Soviet scientific publications on the effects of radiation on plant life, supposedly derived from laboratory experiments, were in fact thinly disguised descriptions of the area contaminated by the disaster.
According to Gyorgy, 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. In 1990 the Soviet government declassified documents pertaining to the disaster.
Mayak
Mayak Production Association refers to an industrial complex that is one of the biggest nuclear facilities in the Russian Federation. It housed plutonium production reactors and a reprocessing plant...
, a nuclear fuel reprocessing plant in Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
(then a part of the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
). It measured as a Level 6 disaster on the International Nuclear Event Scale
International Nuclear Event Scale
The International Nuclear and Radiological Event Scale was introduced in 1990 by the International Atomic Energy Agency in order to enable prompt communication of safety significance information in case of nuclear accidents....
, making it the third most serious nuclear accident ever recorded (after the Chernobyl disaster
Chernobyl disaster
The Chernobyl disaster was a nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine , which was under the direct jurisdiction of the central authorities in Moscow...
, and Fukushima Daiichi nuclear disaster
Fukushima Daiichi nuclear disaster
The is a series of equipment failures, nuclear meltdowns, and releases of radioactive materials at the Fukushima I Nuclear Power Plant, following the Tōhoku earthquake and tsunami on 11 March 2011. The plant comprises six separate boiling water reactors originally designed by General Electric ,...
, both Level 7 on the INES scale). The event occurred in the town of Ozyorsk
Ozyorsk, Chelyabinsk Oblast
Ozyorsk or Ozersk is a closed town in Chelyabinsk Oblast, Russia. Population: It was founded on the shore of the Irtyash Lake in 1945...
, a closed city
Closed city
A closed city or closed town is a settlement with travel and residency restrictions in the Soviet Union and some of its successor countries. In modern Russia, such places are officially known as "closed administrative-territorial formations" ....
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
Kyshtym
Kyshtym is a town in Chelyabinsk Oblast, Russia, located on the eastern slopes of the South Ural Mountains northwest of Chelyabinsk, near the town of Ozyorsk. Population: 36,000 .-History:...
, the nearest known town.
Background
After World War IIWorld War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
lagged behind the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
in development of nuclear weapon
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from relatively small amounts of matter. The first fission bomb test released the same amount...
s, so it started a rapid research and development program to produce a sufficient amount of weapons-grade uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...
and plutonium
Plutonium
Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation...
. The Mayak plant was built in a great hurry between 1945 and 1948. Gaps in Soviet physicists' knowledge about nuclear physics at the time made it difficult to judge the safety
Nuclear safety
Nuclear safety covers the actions taken to prevent nuclear and radiation accidents or to limit their consequences. This covers nuclear power plants as well as all other nuclear facilities, the transportation of nuclear materials, and the use and storage of nuclear materials for medical, power,...
of many decisions. Also, environmental concerns were not taken seriously during the early development stage. All six reactors were on Lake Kyzyltash and used an open cycle cooling system, discharging irradiated water directly back into the lake. Initially Mayak was dumping high-level radioactive waste into a nearby river, which was taking waste to the river Ob
Ob River
The Ob River , also Obi, is a major river in western Siberia, Russia and is the world's seventh longest river. It is the westernmost of the three great Siberian rivers that flow into the Arctic Ocean .The Gulf of Ob is the world's longest estuary.-Names:The Ob is known to the Khanty people as the...
, flowing further down to the Arctic Ocean
Arctic Ocean
The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...
. Later on, Lake Karachay
Lake Karachay
Lake Karachay , sometimes spelled Karachai, is a small lake in the southern Ural mountains in western Russia. Starting in 1951 the Soviet Union used Karachay as a dumping site for radioactive waste from Mayak, the nearby nuclear waste storage and reprocessing facility, located near the town of...
was used for open-air storage.
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
Decay heat
Decay heat is the heat released as a result of radioactive decay. This is when the radiation interacts with materials: the energy of the alpha, beta or gamma radiation is converted into the thermal movement of atoms.-Natural occurrence:...
(though a chain reaction
Chain reaction
A chain reaction is a sequence of reactions where a reactive product or by-product causes additional reactions to take place. In a chain reaction, positive feedback leads to a self-amplifying chain of events....
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.
Explosion
In September 1957, the cooling system in one of the tanks containing about 70–80 tons of liquid radioactive waste failed and was not repaired. The temperature in it started to rise, resulting in evaporation and a chemical explosion of the dried waste, consisting mainly of ammonium nitrate and acetateAcetate
An acetate is a derivative of acetic acid. This term includes salts and esters, as well as the anion found in solution. Most of the approximately 5 billion kilograms of acetic acid produced annually in industry are used in the production of acetates, which usually take the form of polymers. In...
s (see ammonium nitrate bomb
ANFO
ANFO is a widely used bulk industrial explosive mixture. It consists of 94 percent porous prilled ammonium nitrate , that acts as the oxidizing agent and absorbent for the fuel — six percent Number 2 Fuel Oil...
). The explosion, estimated to have a force of about 70–100 tons of TNT threw the concrete lid, weighing 160 tons, into the air. There were no immediate casualties as a result of the explosion, which released an estimated 2 to 50 MCi (74 to 1850 PBq
Becquerel
The becquerel is the SI-derived unit of radioactivity. One Bq is defined as the activity of a quantity of radioactive material in which one nucleus decays per second. The Bq unit is therefore equivalent to an inverse second, s−1...
) of radioactivity.
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
Caesium-137
Caesium-137 is a radioactive isotope of caesium which is formed as a fission product by nuclear fission.It has a half-life of about 30.17 years, and decays by beta emission to a metastable nuclear isomer of barium-137: barium-137m . Caesium-137 is a radioactive isotope of caesium which is formed...
and strontium-90
Strontium-90
Strontium-90 is a radioactive isotope of strontium, with a half-life of 28.8 years.-Radioactivity:Natural strontium is nonradioactive and nontoxic, but 90Sr is a radioactivity hazard...
. This area is usually referred to as the East-Ural Radioactive Trace (EURT).
Aftermath
Because of the secrecy surrounding Mayak, the populations 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."Although vague reports of a "catastrophic accident" began appearing in the western press in April 1958, it was only in 1976 that Zhores Medvedev
Zhores Medvedev
Zhores Aleksandrovich Medvedev is a Russian biologist, historian and dissident. His twin brother is the historian Roy Medvedev.-Biography:Zhores Medvedev and his twin brother Roy Medvedev were born on 14 November 1925 in Tbilisi, Georgia, USSR....
made the nature and extent of the disaster known to the world.
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.
"In 1992, a study conducted by the Institute of Biophysics at the former Soviet Health Ministry in Chelyabinsk found that 8,015 people had died within the preceding 32 years as a result of the accident."
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".
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 demonstrated by Zhores Medvedev, who, after his reference to the disaster in a western publication was derided by western nuclear industry sources, showed that numerous Soviet scientific publications on the effects of radiation on plant life, supposedly derived from laboratory experiments, were in fact thinly disguised descriptions of the area contaminated by the disaster.
According to Gyorgy, who invoked the Freedom of Information Act
Freedom of Information Act (United States)
The Freedom of Information Act is a federal freedom of information law that allows for the full or partial disclosure of previously unreleased information and documents controlled by the United States government. The Act defines agency records subject to disclosure, outlines mandatory disclosure...
to gain access to the relevant Central Intelligence Agency
Central Intelligence Agency
The Central Intelligence Agency is a civilian intelligence agency of the United States government. It is an executive agency and reports directly to the Director of National Intelligence, responsible for providing national security intelligence assessment to senior United States policymakers...
(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. In 1990 the Soviet government declassified documents pertaining to the disaster.
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.External links
- Der nukleare Archipel
- Official documents pertaining to the disaster