View source for Mayak

{{Short description|Nuclear reprocessing plant in Russia}}
{{Other uses}}{{distinguish|Maysak}}
{{Use dmy dates|date=October 2019}}
{{Infobox company
| name = Mayak
| type = [[Federal State Unitary Enterprise]]
| industry = Nuclear energy
| fate = 
| predecessor = <!-- or: | predecessors = -->
| image = Здание профсоюза ПО Маяк.JPG
|image_caption = Mayak headquarters in Ozyorsk
| successor = <!-- or: | successors = -->
| founded = 1948
| founder = <!-- or: | founders = -->
| defunct = <!-- {{End date|df=yes|YYYY|MM|DD}} -->
| hq_location_city = [[Ozyorsk, Chelyabinsk Oblast]]
| hq_location_country = [[Russia]]
| area_served = <!-- or: | areas_served = -->
| key_people = 
| products = 
| owner = <!-- or: | owners = -->
| num_employees = 
| num_employees_year = <!-- Year of num_employees data (if known) -->
| parent = [[Rosatom]]<ref>{{Cite web |title=All enterprises |url=http://www.rosatom.ru/en/all-enterprises/ |url-status=dead |archive-url=https://web.archive.org/web/20170421021455/http://www.rosatom.ru/en/all-enterprises/ |archive-date=21 April 2017 |access-date=18 June 2017 |website=Rosatom.ru }}</ref>
| website = {{URL|po-mayak.ru}}
}}

The '''Mayak Production Association''' ({{langx|ru|Производственное объединение «Маяк»}}, {{lang|ru-Latn|Proizvodstvennoye ob′yedineniye "Mayak"}}, from {{lang|ru|Маяк}} 'lighthouse') is one of the largest nuclear facilities in the Russian Federation, housing [[Production reactor|production reactors]] (''non'' electricity) and a reprocessing plant. The closest settlements are [[Ozyorsk, Chelyabinsk Oblast|Ozyorsk]] to the northwest and Novogornyi to the south.

[[Lavrentiy Beria]] led the Soviet atomic bomb project. He directed the construction of the Mayak plutonium plant in the Southern Urals between 1945 and 1948, in a great hurry and secrecy as part of the [[Soviet Union]]'s [[Soviet atomic bomb project|atomic bomb project]]. The plant had a similar purpose to the [[Hanford Site]] of the [[Manhattan Project]]. Over 40,000 [[gulag]] prisoners and POWs built the factory and the closed nuclear city of Ozyorsk, called at the time by its classified postal code "Chelyabinsk-40".<ref>{{Cite book |last=Brown |first=Kate |title=[[Plutopia: Nuclear Families, Atomic Cities, and the Great Soviet and American Plutonium Disasters]] |publisher=Oxford University Press |year=2013 |isbn=9780199855766 |location=Oxford |oclc=813540523}}</ref> The first reactor, [[A-1 (nuclear reactor)|A-1]], operated from 1948 and fuelled the first nuclear test [[RDS-1]] in 1949. During the [[Cold War]], 10 nuclear reactors were constructed, with a combined power of 7,333 MWth. Of these, four were used for plutonium production, yielding 31 tons of [[weapons-grade plutonium]], out of the Soviet Union's all-time production of 145 tons. The other six reactors primarily produced [[tritium]] for [[thermonuclear weapons]]. In 1990, weapons-grade plutonium production was ceased. 

{{as of|2025|lc=off}}, Mayak is still active, with two reactors in operation at 1,900 MWth. Today the plant primarily produces [[tritium]] for domestic weapons maintenance, and [[plutonium-238]], used by many [[space programs]] for [[Radioisotope thermoelectric generator|radioisotope thermoelectric generators]]. Many other [[radioisotope]]s are commercially sold worldwide, including {{SimpleNuclide|carbon|14|link=yes}}, {{SimpleNuclide|cobalt|60|link=yes}}, {{SimpleNuclide|caesium|137|link=yes}}, {{SimpleNuclide|promethium|147|link=yes}}, {{SimpleNuclide|iridium|193|link=yes}}, {{SimpleNuclide|neptunium|237|link=yes}}, {{SimpleNuclide|americium|241|link=yes}}.<ref name="u810">{{cite web |last=Standring |first=Will |date=2006-07-01 |title=Review of the current status and operations at Mayak Production Association |url=https://www.osti.gov/etdeweb/biblio/20913185 |access-date=2025-05-02 |website=Review of the current status and operations at Mayak Production Association (Technical Report)}}</ref> [[Polonium-210]] produced at Mayak was reportedly used in the 2006 [[poisoning of Alexander Litvinenko]]. It also [[Nuclear reprocessing|reprocesses]] the [[spent nuclear fuel]] from civilian reactors, and manages plutonium from decommissioned nuclear weapons.<ref>{{Cite news |last=Walker |first=Shaun |date=2 July 2017 |title=Russia begins cleaning up the Soviets' top-secret nuclear waste dump |url=https://www.theguardian.com/environment/2017/jul/02/russia-begins-cleaning-up-the-soviets-top-secret-nuclear-waste-dump |access-date=7 July 2017 |work=[[The Guardian]]}}</ref> In recent years, proposals that the plant reprocess waste from foreign nuclear reactors have given rise to controversy.{{Citeneed|date=May 2025}}

The site has had many [[Nuclear and radiation accidents and incidents|radiation accidents]] and [[radioactive contamination]]. In 1949–1951, 76 million m<sup>3</sup> of toxic chemicals and 3.2 million [[Curie (unit)|curie]]s {{convert|750|km2|abbr=on}} of radioactive waste were released into the [[Techa River|Techa river]].<ref name="BuKoWi">{{Cite web |title=Radioactive Contamination of the Techa River and its Effects |url=http://phys4.harvard.edu/~wilson/publications/pp747/techa_cor.htm |url-status=dead |archive-url=https://web.archive.org/web/20050315111114/http://phys4.harvard.edu/%7Ewilson/publications/pp747/techa_cor.htm |archive-date=15 March 2005 |access-date=27 September 2020}}</ref> In 1957, the [[Kyshtym disaster]] occurred at Mayak, releasing 20 million curies in a radioactive cloud across the eastern Urals.<ref>Kostyuchenko & Krestinina 1994, pp. 119–125</ref> It was the [[International Nuclear and Radiological Event Scale|worst nuclear accident]] in history until the [[Chernobyl disaster]], and is still the third most severe.<ref name=":0" /> Mayak is also widely suspected to be the source of the ~200 [[Becquerel|TBq]] (~5400 curies) [[airborne radioactivity increase in Europe in autumn 2017]].<ref name="NYT111217">{{Cite news |last1=Luxmoore |first1=Matthew |last2=Cowell |first2=Alan |date=21 November 2017 |title=Russia, in Reversal, Confirms Radiation Spike |url=https://www.nytimes.com/2017/11/21/world/europe/russia-nuclear-cloud.html |access-date=21 November 2017 |work=[[The New York Times]]}}</ref> Between the first two accidents, 38,000 people were evacuated. Many other communities remained exposed, suffering long-term effects of [[radiation poisoning]].

==Location==
[[File:Satellite image map of Mayak.jpg|thumb|Satellite image/map of the Mayak nuclear facility.]]
[[File:Mayak-FMSF-Cetac-25.jpg|thumb|Fissile Material Storage Facility (FMSF). Looking at the administration building of the storage facility to include all the support facilities. Excavator is one of the pieces of construction equipment procured by the USACE.]]
The nuclear complex is 150&nbsp;km south of [[Ekaterinburg]], between the towns of [[Kasli]] and Tatysh, and 100&nbsp;km northwest of [[Chelyabinsk]]. The closest city, [[Ozyorsk, Chelyabinsk Oblast|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.<ref name="Standring">{{Cite journal |last=Will Standring |year=2006 |title=Review of the current status and operations at Mayak Production Association |url=http://www.nrpa.no/dav/1fbb52ea04.pdf |publisher=[[Norwegian Nuclear Energy Safety Authority|Norwegian Radiation Protection Authority]] |access-date=9 April 2011 |archive-date=3 March 2016 |archive-url=https://web.archive.org/web/20160303174711/http://www.nrpa.no/dav/1fbb52ea04.pdf |url-status=dead }}</ref>

==Design and structure==
Mayak's nuclear facility plant covers about {{convert|90|km2}}. 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 minimise the effects that harmful emissions could potentially have on populated areas. Mayak is surrounded by a ~{{convert|250|km2}} exclusion zone. Nearby is the site of the South Urals nuclear power plant.<ref group=note>This section copied and translated from the German Wikipedia entry for "Mayak", with some grammatical errors corrected</ref>

=== Reactors ===
{{Main article|Soviet atomic bomb project#Plutonium production}}
{| class="wikitable sortable mw-collapsible"
|+Plutonium production reactors in the USSR<ref name="e3522">{{cite journal |last=DIAKOV |first=ANATOLI |date=2011-04-25 |title=The History of Plutonium Production in Russia |journal=Science & Global Security |publisher=Informa UK Limited |volume=19 |issue=1 |pages=28–45 |bibcode=2011S&GS...19...28D |doi=10.1080/08929882.2011.566459 |issn=0892-9882}}</ref>
!Reactor 
name
!Design power 
(MWth)
!Upgraded power 
(MWth)
!Began operation
!Shut down
!Total plutonium 
(tons)
!Design
!Coolant circuit
|-
|A
|100
|900
|19 June 1948
|16 June 1987
|6.138
|[[LWGR]]
|Single-pass
|-
|AV-1
|300
|1200
|5 April 1950
|12 August 1989
|8.508
|[[LWGR]]
|Single-pass
|-
|AV-2
|300
|1200
|6 April 1951
|14 July 1990
|8.407
|[[LWGR]]
|Single-pass
|-
|AV-3
|300
|1200
|15 September 1952
|1 November 1990
|7.822
|[[LWGR]]
|Single-pass
|-
|''AI-IR''
|40
|100
|22 December 1952
|25 May 1987
|0.053
|[[LWGR]]
|Single-pass
|-
|''OK-180''
|100
|233
|17 October 1951
|3 March 1966
|0
|[[Heavy-water reactor|HWR]]
|Closed-circuit
|-
|''OK-190''
|300
|300
|27 December 1955
|8 November 1965
|0
|[[Heavy-water reactor|HWR]]
|Closed-circuit
|-
|''OK-190M''
|300
|300
|16 April 1966
|16 April 1986
|0
|[[Heavy-water reactor|HWR]]
|Closed-circuit
|-
|''LF-2 "Ludmila"''
|800
|800
|May 1988
|In operation
|0
|[[Heavy-water reactor|HWR]]
|Closed-circuit
|-
|''"Ruslan"''
|800
|1100
|12 June 1979
|In operation
|0
|[[LWR]]
|Closed-circuit
|}

=== Notes ===
{{reflist|group=note}}

==History==
Built in total secrecy between 1945 and 1948, the Mayak plant was the first reactor used to create [[plutonium]] for the [[Soviet atomic bomb project]]. In accordance with [[Stalinism|Stalinist]] procedure and supervised by [[NKVD]] Chief [[Lavrentiy Beria]], it was the utmost priority to produce enough weapons-grade material to match the U.S. nuclear superiority following the [[atomic bombings of Hiroshima and Nagasaki]]. Little to no consideration was paid to worker safety or responsible disposal of waste materials, and the reactors were all optimised for plutonium production, producing many tons of contaminated materials and utilising primitive open-cycle cooling systems which directly contaminated the thousands of gallons of cooling water the reactors used every day.<ref>{{Cite web |title=Nuclear History – the forgotten disasters |date=31 July 2012 |url=https://nuclear-news.net/information/nuclear-history/nuclear-history-the-forgotten-disaster/ |access-date=7 July 2017 |publisher=Nuclear-news.net}}</ref><ref name="nti">{{Cite web |title=Mayak Production Association &#124; Facilities |url=http://www.nti.org/learn/facilities/894/ |url-status=live |archive-url=https://web.archive.org/web/20170706151057/http://www.nti.org/learn/facilities/894/ |archive-date=6 July 2017 |access-date=7 July 2017 |publisher=NTI}}</ref>

Lake Kyzyltash was the largest natural lake capable of providing cooling water to the reactors; it was rapidly contaminated via the open-cycle system. The closer [[Lake Karachay]], too small to provide sufficient cooling water, was used as a dumping ground for large quantities of high-level radioactive waste too "hot" to store in the facility's underground storage vats. The original plan was to use the lake to store highly radioactive material until it could be returned to the Mayak facility's underground concrete storage vats, but this proved impossible due to the lethal levels of radioactivity (see [[Pollution of Lake Karachay]]). The lake was used for this purpose until the [[Kyshtym Disaster]] in 1957, in which the underground vats exploded due to a faulty cooling system. This incident caused widespread contamination of the entire Mayak area (as well as a large swath of territory to the northeast). This led to greater caution among the administration, fearing international attention, and caused the dumping grounds to be spread out over a variety of areas (including several lakes and the [[Techa River]], along which many villages lay).<ref name="nti" />

===Kyshtym disaster===
{{Main|Kyshtym disaster}}
[[File:Fissile-material-storage-facility.jpg|thumb|Fissile Material Storage Facility (FMSF). Looking at the south side of the main Administration Building and security building of the storage facility.]]
Working conditions at Mayak resulted in severe health hazards and many accidents.<ref>{{Cite journal |last=Larin |first=Vladislav |date=September–October 1999 |title=Mayak's walking wounded |journal=Bulletin of the Atomic Scientists |volume=55 |issue=5 |pages=20–27 |doi=10.2968/055005008}}</ref> The most notable accident occurred on 29 September 1957, when the failure of the cooling system for a tank storing tens of thousands of tons of dissolved nuclear waste resulted in a chemical (non-nuclear) explosion having an energy estimated at 75 tons of [[trinitrotoluene|TNT]] (310 [[joule|gigajoules]]). This released 740 PBq (20 MCi) of fission products, of which 74 PBq (2 MCi) drifted off the site, creating a contaminated region of {{convert|15,000|–|20,000|km2}} called the East Urals Radioactive trace.<ref name=am/><ref name=Standring2009 /> Subsequently, an estimated 49 to 55 people died of [[radiation-induced cancer]],<ref name="Standring2009">{{Cite journal |last1=Standring |first1=William J.F. |last2=Dowdall, Mark and Strand, Per |year=2009 |title=Overview of Dose Assessment Developments and the Health of Riverside Residents Close to the "Mayak" PA Facilities, Russia |journal=International Journal of Environmental Research and Public Health |volume=6 |issue=1 |pages=174–199 |doi=10.3390/ijerph6010174 |issn=1660-4601 |pmc=2672329 |pmid=19440276|doi-access=free }}</ref> 66 were diagnosed with [[chronic radiation syndrome]],<ref name="Guskova2001">{{Cite book |last1=Gusev |first1=Igor A. |url=https://books.google.com/books?id=p6b4qDorN4wC&pg=PA15 |title=Medical Management of Radiation Accidents |last2=Gusʹkova |first2=Angelina Konstantinovna |last3=Mettler |first3=Fred Albert |date=28 March 2001 |publisher=CRC Press |isbn=978-0-8493-7004-5 |pages=15–29 |access-date=11 June 2012 |archive-url=https://web.archive.org/web/20140102131827/http://books.google.com/books?id=p6b4qDorN4wC&pg=PA15 |archive-date=2 January 2014 |url-status=live}}</ref> 10,000 people were evacuated from their homes, and 470,000 people were exposed to radiation.<ref name=":0" />

The [[Soviet Union]] did not release news of the accident and denied it happened for nearly 30 years. Residents of Chelyabinsk district in the Southern Urals reported observing "polar-lights" in the sky near the plant, and American aerial spy photos had documented the destruction caused by the disaster by 1960.<ref>{{Cite web |date=2012 |title=The nuclear disaster of Kyshtym 1957 and the politics of the Cold War |url=http://www.environmentandsociety.org/arcadia/nuclear-disaster-kyshtym-1957-and-politics-cold-war |url-status=live |archive-url=https://web.archive.org/web/20141026122154/http://www.environmentandsociety.org/arcadia/nuclear-disaster-kyshtym-1957-and-politics-cold-war |archive-date=26 October 2014 |access-date=25 October 2014 |website=Arcadia |publisher=Environment and Society}}</ref> This nuclear accident, the Soviet Union's worst before the [[Chernobyl disaster]], is categorised as a Level 6 "Serious Accident" on the 0–7 [[International Nuclear Events Scale]].

When [[Zhores Medvedev]] exposed the disaster in a 1976 article in ''[[New Scientist]]'', some exaggerated claims circulated in the absence of any verifiable information from the Soviet Union. 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."<ref name="p">Pollock, Richard, 1978. "Soviets Experience Nuclear Accident," ''Critical Mass Journal 3'' pp.7–8</ref> As Zhores wrote, "Hundreds of square miles were left barren and unusable for decades and maybe centuries. Hundreds of people died, thousands were injured and surrounding areas were evacuated."<ref>[[Zhores Medvedev]], ''The Australian'', 9 December 1976</ref> Professor Leo Tumerman, former head of the Biophysics Laboratory at the Institute of Molecular Biology in Moscow, disclosed what he knew of the accident around the same time. Russian documents gradually declassified from 1989 onward show the true events were less severe than rumoured.

According to Gyorgy,<ref>Gyorgy, A. et al., 1980. [https://archive.org/details/nonukeseveryones0000gyor/page/13 ''No Nukes: Everyone's Guide to Nuclear Power'']. South End Press {{ISBN|0-89608-006-4}}. pp. 13, 128</ref> who invoked the [[Freedom of Information Act (United States)|Freedom of Information Act]] to open up the relevant [[Central Intelligence Agency]] (CIA) files, the CIA knew of the 1957 Mayak accident, but kept it secret to prevent adverse consequences for the fledgling US nuclear industry. "[[Ralph Nader]] surmised that the information had not been released because of the reluctance of the CIA to highlight a nuclear accident in the USSR, that could cause concern among people living near nuclear facilities in the USA."<ref name=p/> Only in 1992, shortly after the fall of the USSR, did the Russians officially acknowledge the accident.

===1968 criticality incident===
[[File:Mayak-FMSF-Cetac-36.jpg|thumb|Looking at storage facility processing materials, controls, accountability, and fissile material container storage from south-west angle.]]
In December 1968, the facility was experimenting with plutonium purification techniques. Two operators were using an "unfavourable geometry vessel in an improvised and unapproved operation as a temporary vessel for storing plutonium organic solution".<ref name="McLaughlin">McLaughlin et al. "[http://www.orau.org/ptp/Library/accidents/la-13638.pdf A Review of Criticality Accidents] {{webarchive|url=https://web.archive.org/web/20070927235352/http://www.orau.org/ptp/Library/accidents/la-13638.pdf |date=27 September 2007 }}" by Los Alamos National Laboratory (Report LA-13638), May 2000</ref> "Unfavourable geometry" means that the vessel was too compact, reducing the amount of plutonium needed to achieve a critical mass to less than the amount present. After most of the solution had been poured out, there was a flash of light and heat. After the complex had been evacuated, the shift supervisor and radiation control supervisor re-entered the building. The shift supervisor then entered the room of the incident, caused another, larger nuclear reaction and irradiated himself with a deadly dose of radiation.<ref>[http://www.johnstonsarchive.net/nuclear/radevents/1968USSR2.html "Mayak Enterprise criticality accident, 1968."] Mayak Enterprise criticality accident, 1968. Accessed 10 December 2017.</ref>

===2017 radiation release===
{{Main|Airborne radioactivity increase in Europe in autumn 2017}}
Abnormally high levels of radiation were reported in the area of the facility in November 2017.<ref name="auto">{{Cite news |last=Devlin |first=Shaun Walker Hannah |date=21 November 2017 |title=Russian nuclear facility denies it is source of high radioactivity levels |newspaper=The Guardian |url=https://www.theguardian.com/world/2017/nov/21/russia-radioactivity-986-times-norm-nuclear-accident-claim |via=www.theguardian.com}}</ref> Simultaneously, traces of radioactive manmade isotope [[Ruthenium]]-106 spread across Europe in September and October. Such a release had not been seen on a continental scale since the Chernobyl accident. In January 2018, the French Institute of Radioprotection and Nuclear Security (IRSN) reported that the source of the contamination is located in the Volga – Southern Ural region between 25 and 28 September for a duration of less than 24 hours. The report excludes the possibility of an accidental release from a nuclear reactor, stating that it seems related with irradiated fuels processing or the production of sources from fission products solution. It may point to Mayak's aborted attempt to manufacture a capsule of highly radioactive component cerium-144, for the [[Borexino#SOX project|SOX project]] in Italy.<ref name=":1">{{Cite web |last=IRSN |date=January 2018 |title=Report on IRSN investigations of Ru 106 in Europe in October 2017 |url=http://www.irsn.fr/FR/Actualites_presse/Actualites/Documents/IRSN_Report-on-IRSN-investigations-of-Ru-106-in-Europe-in-october-2017.pdf |access-date=16 February 2018 |website=www.irsn.fr}}</ref> Both the Russian government and Rosatom denied at the time that another accidental leak took place at Mayak.<ref>{{Cite news |date=14 February 2018 |title=Mishandling of spent nuclear fuel in Russia may have caused radioactivity to spread across Europe |language=en |work=Science {{!}} AAAS |url=https://www.science.org/content/article/mishandling-spent-nuclear-fuel-russia-may-have-caused-radioactivity-spread-across |access-date=16 February 2018}}</ref> The release of a cloud of ruthenium-106 is similar to the [[B205]] reprocessing accident in Britain in 1973.<ref>{{cite journal|url=https://network.bellona.org/content/uploads/sites/3/Sellaengweb.pdf|title=Sellafield (§2.1—The reprocessing plant B204)|page=20|date=2003-06-01|volume=2003|issue=8|accessdate=2021-10-21|publisher=The Bellona Foundation|journal=[[Bellona Report]]|first=Erik|last=Martiniussen|isbn=82-92318-08-9|issn=0806-3451}}</ref>

==Environmental impact==
In the early years of its operation, the Mayak plant directly discharged high-level nuclear waste into several small lakes near the plant, and into the [[Techa River]], whose waters ultimately flow into the [[Ob River]]. According to the data of the Department of Natural Resources in the Ural Region, in the year 2000, more than {{convert|250|e6m3|e9cuft|abbr=off}} of water containing thousands of curies of tritium, strontium, and cesium-137 were discharged into the Techa River. The tritium concentration alone in the river near the village of Muslyumovo exceeds the permissible limit by 30 times.<ref name=":0">{{Cite web |date=6 January 2014 |title=Kyshtym Disaster |url=http://www.nuclear-heritage.net/index.php/Kyshtym_Disaster |url-status=live |archive-url=https://web.archive.org/web/20141026121347/http://www.nuclear-heritage.net/index.php/Kyshtym_Disaster |archive-date=26 October 2014 |access-date=25 October 2014 |website=Nuclear-Heritage.net}}</ref>

Rosatom, a state-owned nuclear operations corporation, began to resettle residents of Muslyumovo in 2006. However, only half of the residents of the village were moved.&nbsp;<ref name=":0" /> People continue to live in the immediate area of the plant, including [[Ozyorsk, Chelyabinsk Oblast|Ozyorsk]] and other downstream areas. Residents report no problems with their health and the health of Mayak plant workers. However, these claims lack verification, and many who worked at the plant in 1950s and 1960s subsequently died from the effects of radiation.<ref>{{Cite journal |last1=Koshurnikova |first1=N.A. |last2=Shilnikova |first2=N.S. |last3=Sokolnikov |first3=M.E. |last4=Bolotnikova |first4=M.G. |last5=Okatenko |first5=P.V. |last6=Kuznetsova |first6=I.S. |last7=Vasilenko |first7=E.K. |last8=Khokhryakov |first8=V.F. |last9=Kreslov |first9=V.V. |year=2006 |title=Medical-dosimetry registry of workers at the 'Mayak' production association |url=http://www.inderscience.com/search/index.php?action=record&rec_id=9516&prevQuery=&ps=10&m=or |journal=International Journal of Low Radiation |publisher=Inderscience Publishers |volume=2 |issue=3/4 |pages=236–242 |doi=10.1504/IJLR.2006.009516 |access-date=6 January 2012|url-access=subscription }}</ref><ref>{{Cite journal |last1=Azizova |first1=Tamara V. |last2=Muirhead |first2=Colin R. |last3=Moseeva |first3=Maria B. |last4=Grigoryeva |first4=Evgenia S. |last5=Sumina |first5=Margarita V. |last6=O’Hagan |first6=Jacqueline |last7=Zhang |first7=Wei |last8=Haylock |first8=Richard J. G. E. |last9=Hunter |first9=Nezahat |year=2011 |title=Cerebrovascular diseases in nuclear workers first employed at the Mayak PA in 1948–1972 |journal=Radiation and Environmental Biophysics |publisher=Springerlink |volume=50 |issue=4 |pages=539–552 |doi=10.1007/s00411-011-0377-6 |pmid=21874558|s2cid=1279837 }}</ref> The administration of the Mayak plant has been repeatedly criticized in recent years by Greenpeace and other environmental advocates for environmentally unsound practices.

==List of accidents==
[[File:Mayak-FMSF-Cetac-37.jpg|thumb|Fissile Material Storage Facility (FMSF). The building is the ventilation center of the storage facility. The ventilation tunnel showing in the north of the ventilation centre.]]

The Mayak plant is associated with two other major nuclear accidents. The first occurred as a result of heavy rains causing [[Lake Karachay]], a dried-up radioactively polluted lake (used as a dumping basin for Mayak's radioactive waste since 1951), to release radioactive material into surrounding waters. The second occurred in 1967 when wind spread dust from the bottom of Lake Karachay over parts of [[Ozyorsk, Chelyabinsk Oblast|Ozyorsk]]; over 400,000 people were irradiated.{{quantify|date=October 2016}}.<ref name="am">[http://www1.american.edu/projects/mandala/TED/ural.htm A report on the 1957 accident and on endemic radioactive pollution at Mayak] {{webarchive|url=https://web.archive.org/web/20100714130850/http://www1.american.edu/projects/mandala/TED/ural.htm |date=14 July 2010 }}</ref>{{better source needed|date=October 2016}}

===Major accidents at Mayak, 1953–1998===
''Source'':<ref name="unsc">{{Cite web |year=2011 |title=Sources and Effects of Ionising Radiation – 2008 Report to the General Assembly |url=http://www.unscear.org/docs/reports/2008/11-80076_Report_2008_Annex_C.pdf |url-status=live |archive-url=https://web.archive.org/web/20130531015743/http://www.unscear.org/docs/reports/2008/11-80076_Report_2008_Annex_C.pdf |archive-date=31 May 2013 |website=[[United Nations Scientific Committee on the Effects of Atomic Radiation]] |at=Annex C: Radiation exposures in accidents |volume=II Scientific Annexes C, D, and E}}</ref>
* 15 March 1953 – [[Criticality accident]]. Contamination of plant personnel occurred.
* 13 October 1955 – Rupture of process equipment and the destruction of a process building.
* 21 April 1957 – Criticality accident. One operator died from receiving over 3000 rad. Five others received doses of 300 to 1,000 rem and temporarily became sick with radiation poisoning.
* 29 September 1957 – [[Kyshtym disaster]].
* 2 January 1958 – Criticality accident in SCR plant. Plant workers conducted experiments to determine the critical mass of enriched uranium in a cylindrical container with different concentrations of uranium in solution. Personnel received doses from 7600 to 13,000 rem, resulting in three deaths and one case of blindness caused by radiation sickness.  
* 12 May 1960 – Criticality accident. Five people were contaminated.
* 26 February 1962 – Destruction of equipment. An explosion occurred in the absorption column.
* 9 July 1962 – Criticality accident.
* 16 December 1965 – Criticality accident. Seventeen individuals received exposure to small amounts of radiation over a period of 14 hours.
* 10 December 1968 – Criticality accident. Plutonium solution was poured into a cylindrical container with dangerous geometry. One person died, another took a high dose of radiation and radiation sickness, after which he had both legs and his right arm amputated.
* 11 February 1976 – Unsafe actions of staff development at the radiochemical plant caused an autocatalytic reaction of concentrated nitric acid and organic liquid complex composition. The device exploded, contaminating the repair zone and areas around the plant. The incident merited an [[International Nuclear Event Scale]] rating of 3.
* 10 February 1984 – Explosion. 
* 16 November 1990 – Explosion. Two people received burns and one was killed.
* 17 July 1993 –  Accident at radioisotope plant, resulting in the destruction of the absorption column and release into the environment of a small amount of α-[[aerosol]]s. Radiation emission was localised at the manufacturing facility of the shop.
* 8 February 1993 – Depressurisation of a pipeline caused {{convert|2|m3}} of radioactive slurry (about {{convert|100|m2}} of contaminated surface) to leak to the surface of the pulp radioactive activity of about 0.3 Ci. Radioactive trace was localised, contaminated soil removed.
* 27 December 1993 – Incident at radioisotope plant where the replacement of a filter resulted in the release into the atmosphere of radioactive aerosols. Emissions were on the α-activity of 0.033 Ci, and β-activity of 0.36 mCi.
* 4 February 1994 – Recorded increased release of radioactive aerosols: the β-activity of 2-day levels of Cs-137 subsistence levels, the total activity of 7.15 mCi.
* 30 March 1994 – Recorded excess daily release of Cs-137 in 3, β-activity – 1,7, α-activity – by 1.9 times. In May 1994 the ventilation system of the building of the plant spewed activity 10.4 mCi β-aerosols. Emission of Cs-137 was 83% of the control level.
* 7 July 1994 – The control plant detected a radioactive spot area of several square decimetres. Exposure dose was 500 millirems per second. The spot was formed by leaking sewage.
* 31 August 1994 – Registered an increased release of radionuclides to the atmospheric pipe building reprocessing plant (238.8 mCi, with the share of Cs-137 was 4.36% of the annual emission limit of this radionuclide). The reason for the release of radionuclides was depressurisation of VVER-440 fuel elements during the operation segments idle all SFA (spent fuel assemblies) as a result of an uncontrollable arc.
* 24 March 1995 –  Recorded excess of 19% of normal loading apparatus plutonium, which can be regarded as a dangerous nuclear incident.
* 15 September 1995 – High-level liquid radioactive waste (LRW) was found in flow of cooling water. Operation of a furnace into the regulatory regime has been discontinued.
* 21 December 1995 – Cutting of a thermometric channel exposed four workers (1.69, 0.59, 0.45, 0.34 rem) when operators violated process procedures.
* 24 July 1995 –  Cs-137 aerosols released, the value of which amounted to 0.27% of the annual value of MPE for the enterprise. 
* 14 September 1995 – Replacement covers and lubrication step manipulators registered a sharp increase in airborne α-nuclides.
* 22 October 1996 – Depressurisation occurred in a coil while channeling cooling water from one storage tanks of high-level waste. The result was contaminated pipe cooling system repositories. As a result of this incident, 10 people were exposed to radiation dose of 2.23 to 48 milli-[[Sievert]]s.
* 20 November 1996 – A chemical-metallurgical plant in the works on the electrical exhaust fan caused aerosol release of radionuclides into the atmosphere, which made up 10% of the allowed annual emissions of the plant.
* 27 August 1997 – In building RT-1 in one of the rooms was found to be contaminated floor area of 1 to 2 m<sup>2</sup>, the dose rate of gamma radiation from the spot was between 40 and 200 mR / s.
* 6 October 1997 – Recorded increasing radioactivity in the assembly building, the RT-1. Measurement of the exposure dose indicated up to 300 mR / s.
* 23 September 1998 – While increasing power output of reactor P-2 ("Lyudmila") after engaging automatic protection allowable power level was exceeded by 10%. As a result, the three channels of the fuel rod seal failed, resulting in the contamination of equipment and pipelines of the first circuit.<ref group=Major_accidents_note>All of the above list transferred directly from the Russian Wikipedia entry for "Mayak". Translated and some grammatical errors corrected</ref>

====Notes====
{{reflist|group=Major_accidents_note}}

===More recent major accidents===
* In 2003, the plant's operating licence was revoked temporarily due to liquid radioactive waste handling procedures resulting in waste being disposed into open water.<ref>{{Cite web |title=Revoked License Grinds Mayak to a Halt |url=http://www.bellona.org/english_import_area/international/russia/nuke_industry/siberia/mayak/27922 |url-status=dead |archive-url=https://web.archive.org/web/20110811025233/http://www.bellona.org/english_import_area/international/russia/nuke_industry/siberia/mayak/27922 |archive-date=11 August 2011 |access-date=6 March 2011}}</ref>
* In June 2007, an accident involving a radioactive pulp occurred over a two-day period.<ref name="bellona.org">{{Cite web |title=Radioactive material leaks during transport at Mayak - no one hurt, says plant |url=http://www.bellona.org/articles/articles_2007/Mayak_leak |url-status=dead |archive-url=https://web.archive.org/web/20121012042538/http://www.bellona.org/articles/articles_2007/Mayak_leak |archive-date=12 October 2012 |access-date=6 March 2011}}</ref>
* In October 2007, a valve failure during transport of a radioactive liquid resulted in spilling of a radioactive material.<ref name="bellona.org" />
* In 2008, a repair worker was injured during a "pneumatic" incident, involving a quantity of alpha emitter release. The worker's hand was injured and the wound contaminated. The worker's finger was amputated in an attempt to minimize spread of alpha-particle emitters throughout his body and subsequent radiological consequences.<ref>{{Cite web |title=UPDATE: Accident at Mayak leads to apparently contained radiation leak, and seriously injures one worker |url=http://www.bellona.org/articles/articles_2008/another_mayak_incident |url-status=dead |archive-url=https://web.archive.org/web/20110725061400/http://www.bellona.org/articles/articles_2008/another_mayak_incident |archive-date=25 July 2011 |access-date=6 March 2011}}</ref>
*In September 2017, possible association with the [[airborne radioactivity increase in Europe in autumn 2017]].<ref name="auto" /> Russia confirms 'extremely high' readings of radioactive pollution in Argayash, a village in the Chelyabinsk region of the southern Urals.<ref>{{Cite news |title=Russia confirms 'extremely high' readings of radioactive pollution |work=Yahoo News |url=https://www.yahoo.com/news/russia-confirms-extremely-high-readings-radioactive-pollution-184627359.html |access-date=3 December 2017}}</ref> Argayash is located 10 miles south of the Mayak plant. In January 2018, the French Institute of Radioprotection and Nuclear Security (IRSN) reported that Mayak could be the cause of the contamination.<ref name=":1" /> The radioactivity was due to [[Ru-106]] indicating release from a late stage in the reprocessing (i.e. after the Ru-106 had been separated from other isotopes).<ref>{{Cite news |title=Mysterious radioactive leak that swept Europe came from Russia, study confirms despite Kremlin denial |work=Yahoo News |url=https://www.independent.co.uk/news/radioactive-leak-russia-radiation-ural-mountains-ruthenium-fukushima-a9025631.html |archive-url=https://ghostarchive.org/archive/20220512/https://www.independent.co.uk/news/radioactive-leak-russia-radiation-ural-mountains-ruthenium-fukushima-a9025631.html |archive-date=12 May 2022 |url-access=subscription |url-status=live |access-date=30 July 2019}}</ref><ref>{{Cite journal |last=Masson |first=O. |display-authors=etal. |date=2019 |title=Airborne concentrations and chemical considerations of radioactive ruthenium from an undeclared major nuclear release in 2017 |journal=PNAS |volume=116 |issue=34 |pages=16750–16759 |doi=10.1073/pnas.1907571116|pmid=31350352 |pmc=6708381 |bibcode=2019PNAS..11616750M |doi-access=free }}</ref>

==See also==
*''[[City 40 (film)|City 40]]''
*[[List of civilian nuclear accidents]]
*[[List of military nuclear accidents]]
*[[Nuclear and radiation accidents and incidents]]
*[[Ozyorsk, Chelyabinsk Oblast]]
*[[Radioactive contamination]]
*[[Radioactive waste]]
*[[Reprocessed uranium]]
*[[Techa River]], the radioactive river

==References==
{{Reflist}}

==External links==
{{Commons category|Mayak nuclear facility}}
*{{Official website|www.po-mayak.ru}} {{in lang|ru}}

{{Hidden Nuclear Power Plants in Russia}}
{{Nuclear fission reactors}}
{{Rosatom}}
{{Authority control}}

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[[Category:Nuclear technology in the Soviet Union]]