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Fukushima nuclear disaster

During the 2011 Fukushima nuclear disaster in Japan, three nuclear reactors were damaged by explosions.
International humanitarian flight undergoes radioactive decontamination
Water tower vehicles from major fire departments have been integral to the emergency cooling operations

The Fukushima nuclear disaster is a series of ongoing equipment failures, reactor meltdowns, and releases of radioactive materials at the Fukushima Daiichi Nuclear Power Plant, following the Tōhoku earthquake and tsunami on March 11, 2011.[1][2] The plant has six separate Nuclear reactors maintained by the Tokyo Electric Power Company (TEPCO). The accident is the second biggest nuclear accident after the 1986 Chernobyl disaster, but more complex as all reactors are involved.[3]

At the time of the quake, reactor 4 had been de-fueled while 5 and 6 were in cold shutdown for planned maintenance.[4] The remaining reactors shut down automatically after the earthquake, but the entire plant was flooded, including low-lying generators and electrical switchgear in reactor basements and external pumps for supplying cooling seawater. The connection to the electrical grid was broken. All power for cooling was lost and reactors started to overheat. There was a partial core meltdown in reactors 1, 2, and 3; hydrogen explosions destroyed the upper part of the buildings housing reactors 1, 3, and 4; an explosion damaged the containment inside reactor 2; fires broke out at reactor 4. Despite being initially shutdown, reactors 5 and 6 began to overheat. Spent nuclear fuel rods stored in pools in each reactor building overheated as water levels in the pools dropped.

Fears of radiation leaks led to a 20 km (12 mi) radius evacuation around the plant while workers suffered radiation exposure and were temporarily moved out at various times. Grid power was restored to parts of the plant on 20 March, but machinery for reactors 1 through 4, damaged by floods, fires and explosions, was still not working.[5] Flooding with radioactive water through the basements of units 1–4 continues to prevent access to carry out repairs.[6] Measurements in areas of northern Japan 30–50 km from the plant showed radioactive caesium levels high enough to cause concern.[7] Food grown in the area was banned from sale. It was suggested that worldwide measurements of iodine-131 and caesium-137 indicate that the releases from Fukushima are of the same order of magnitude as the releases of those isotopes from the Chernobyl disaster in 1986;[8][9][10]

Tokyo officials said that tap water should not be used to prepare food for children.[11][12] Plutonium contamination has been detected in the soil at two sites in the plant.[13] Two workers hospitalized as a precaution on 25 March had been exposed to between 2000 and 6000 mSv of radiation at their ankles when standing in water in unit 3.[14][15][16] Radiation levels varied widely over time and location.[17]

The nuclear emergencies at Japan's Fukushima I and other nuclear facilities raised questions about the future of nuclear power.[18][19][20][21][22] The radioactive substance from the nuclear ingredients can cause numerous cancers to all creatures including human beings. This can especially cause deformity in pregnant women and the fetus. And the radioactive substance doesn't disappear in a few years, and it continues to wander in many creatures' bodies for centuries. Also, it is spreaded in the ocean through the moving of tap water, freshwater, etc. Thus, the earth is seriously damaged by it.[23] Platts, an energy news website, said that "the crisis at Japan's Fukushima nuclear plants has prompted leading energy-consuming countries to review the safety of their existing reactors and cast doubt on the speed and scale of planned expansions around the world".[24] Following the Fukushima nuclear disaster, the International Energy Agency halved its estimate of additional nuclear generating capacity to be built by 2035.[25]

Japan said that they will start releasing radioactive water into the ocean starting in 2023. They said they will continue doing this in segments through the next 40 years.[26]

Fukushima Nuclear Disaster Media

  • Appearance of Unit 3 after the explosion on 15 March 2011.

  • Cross-section of a typical BWR Mark I containment as used in units 1 to 5.RPV: reactor pressure vesselDW: drywell enclosing reactor pressure vesselWW: wetwell – torus-shaped all around the base enclosing steam suppression pool. Excess steam from the drywell enters the wetwell water pool via downcomer pipes.SFP: spent fuel pool areaSCSW: secondary concrete shield wall

  • Diagram of the cooling systems of a BWR

  • The height of the tsunami that struck the station approximately 50 minutes after the earthquake.A: Power station buildings B: Peak height of tsunami C: Ground level of site D: Average sea level E: Seawall to block waves

  • Aerial view of the station in 1975, showing separation between units 5 and 6, and 1–4. Unit 6, not completed until 1979, is seen under construction.

  • The Fukushima No.1 reactor control room in 1999

  • Map of contaminated areas around the plant (22 March – 3 April 2011)

  • Radiation measurements from Fukushima Prefecture, March 2011

  • Seawater-contamination along coast with Caesium-137, from 21 March until 5 May 2011 (Source: GRS)

Related pages

References

  1. ↑ Japan's unfolding disaster 'bigger than Chernobyl'. New Zealand Herald. 2 April 2011. http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=10716671. Retrieved 3 May 2011. 
  2. ↑ "Explainer: What Went Wrong in Japan's Nuclear Reactors". IEEE Spectrum. 4 April 2011. Archived from the original on 2011-07-04. Retrieved 2011-05-03.
  3. ↑ "Analysis: A month on, Japan nuclear crisis still scarring," International Business Times (Australia). 9 April 2011, retrieved 12 April 2011; excerpt, According to James Acton, Associate of the Nuclear Policy Program at the Carnegie Endowment for International Peace, "Fukushima is not the worst nuclear accident ever but it is the most complicated and the most dramatic ... This was a crisis that played out in real time on TV. Chernobyl did not." Archived 18 April 2011 at WebCite
  4. ↑ Black, Richard (15 March 2011). BBC News – Reactor breach worsens prospects. BBC News. Archived from the original on 16 March 2011. https://www.webcitation.org/5xDYTkU7P?url=http://www.bbc.co.uk/news/science-environment-12745186. Retrieved 23 March 2011. 
  5. ↑ Stricken Reactors May Get Power Sunday, The Wall Street Journal, 19 March 2011
  6. ↑ Julie Makinen, Ralph Vartabedian (9 April 2011). "Containing a calamity creates another nuclear nightmare". Sydney Morning Herald.
  7. ↑ "Caesium fallout from Fukushima rivals Chernobyl". New Scientist. Archived from the original on 30 March 2011. Retrieved 30 March 2011.
  8. ↑ "Aktuelle Informationen". Web site of the Central Institute for Meteorology and Geodynamics (ZAMG), Austria's national weather service agency (data in German). Archived from the original on 2011-04-29. Retrieved 2011-05-03.
  9. ↑ "Fukushima radioactive fallout nears Chernobyl levels". New Scientist. Archived from the original on 25 March 2011. Retrieved 25 November 2011.
  10. ↑ Charlie Martin. "New Scientist and the Wall of Zeros". Pajamas Media. Archived from the original on 2011-04-29. Retrieved 2011-05-03.
  11. ↑ Japan mulls Fukushima food ban: IAEA, Reuters, 19 March 2011 Archived 2011-03-21 at the Wayback Machine
  12. ↑ Justin McCurry in Osaka (23 March 2010). "Tokyo water unsafe for infants after high radiation levels detected". Guardian (London). http://www.guardian.co.uk/world/2011/mar/23/tokyo-water-unsafe-infants. Retrieved 23 March 2011. 
  13. ↑ TEPCO (28 March 2011). "Results of Pu measurement in the soil in Fukushima Daiichi Nuclear Power Plant". Press release. http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110328e14.pdf. Retrieved 7 April 2011. 
  14. ↑ Jolly, David (27 March 2011). "Higher Radiation Levels Found at Japanese Reactor". The New York Times. https://www.nytimes.com/2011/03/28/world/asia/28japan.html. Retrieved 27 March 2011. 
  15. ↑ "Fukushima Daiichi Nuclear Accident Update (27 March, 03:00 UTC)". International Atomic Energy Agency. 27 March 2011. Archived from the original on 20 April 2011. Retrieved 27 March 2011.
  16. ↑ KANAKO Takahara; KAZUAKI Nagata (26 March 2011). "Level of iodine-131 in seawater off chart". Japan Times. Retrieved 27 March 2011.
  17. ↑ "Radiation in everyday life". IAEA. Archived from the original on 2013-10-19. Retrieved 2011-05-03.
  18. ↑ Nuclear Renaissance Threatened as Japan’s Reactor StrugglesBloomberg, published March 2011. Retrieved 2011-03-14. Archived 2011-03-15 at the Wayback Machine
  19. ↑ Analysis: Nuclear renaissance could fizzle after Japan quakeReuters, published 2011-03-14. Retrieved 2011-03-14. Archived 2011-03-16 at the Wayback Machine
  20. ↑ Japan nuclear woes cast shadow over U.S. energy policy Archived 2015-09-24 at the Wayback Machine Reuters, published 2011-03-13. Retrieved 2011-03-14.
  21. ↑ Nuclear winter? Quake casts new shadow on reactorsMarketWatch, published 2011-03-14. Retrieved 2011-03-14. Archived 2011-03-16 at the Wayback Machine
  22. ↑ Will China's nuclear nerves fuel a boom in green energy? Channel 4, published 2011-03-17. Retrieved 2011-03-17.
  23. ↑ mlblevins (2011-06-04). "Effects of Radioactive Pollution". Help Save Nature. Retrieved 2022-10-17.
  24. ↑ "NEWS ANALYSIS: Japan crisis puts global nuclear expansion in doubt". Platts. 21 March 2011.
  25. ↑ Gauging the pressure. The Economist. 28 April 2011. Archived from the original on 2011-05-05. https://www.webcitation.org/5yS4uk6C2?url=http://www.economist.com/node/18621367?story_id=18621367. Retrieved 2011-05-04. 
  26. ↑ "Japan to start releasing Fukushima water into sea in 2 years". Associated Press. Retrieved August 22, 2023.
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