Nuclear Disaster in Japan

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Nuclear Disaster in Japan

As a result of a tsunami and several earthquakes the Fukushima 1 (Daiichi)[1] atomic power plant in Japan experienced a nuclear catastrophe of level INES 6[2] including several explosions, failing cooling systems, meltdown of fuel elements and releases of high amounts of radioactivity since March 11, 2011. Unit 1 exploded on March 12, 2011 at 7.30 AM GMT[3], unit 3 exploded two days later on March 14 at 2.01 AM GMT[4][5][6] and eventually also unit 2 blasted in the following night (14/3/11 9.10 PM GMT) damaging the reactor core and as officially confirmed releasing serious amounts of radiation[7][8]. There is a risk of a nuclear meltdown in unit 2 as the fuel rods have been damaged, the operator says[8]. Also a fire occured on March 15 at 0.40 AM GMT at unit 4[8] - a reactor unit that had not even been in operation when the Tsunami hit the Japanese coast last Friday.

An atomic power emergency has been declared by the Japanese government on Saturday March 12 while up to 300,000 residents had been evacuated[1][7]. Several emergency power generators failed supplying the emergency cooling systems with electricity[2]. The authorities confirmed the release of radioactive elements such as caesium and iodine[9]. Independent experts say that a nuclear meltdown must have happened. According to the German news "Tagesschau" Japanese officials also confirmed a nuclear meltdown in Fukushima[10]. This had been confirmed by a statement of Chief Secretary Yukio Edano on Sunday saying that at least one nuclear meltdown occuredCite error: Closing </ref> missing for <ref> tag. "The cores of the three reactors are believed to have partially melted", the Japanese news agency Kyodo reported on Tuesday Morning[8][11].

Damages of the containment

On Saturday March 12 the Japanese authorities claimed the reactor pressure vessel of unit 1 of Fukushima 1 wouldn't have been damaged. But this is in conflict with the officially confirmed releases of Caesium. Friday evening the authorities already had claimed there wouldn't have been any danger of radioactivity releases. First independent meassurements of radiation showed a serious of radioactivity even in a certain distance to the crashed reactor units[12].

Collapsed MOX reactor increasening threats at Fukushima I

Around 9 PM GMT Saturday March 12 evening Reuters informed about Fukushima 1 unit 3 that "the emergency cooling system is no longer functioning (...) as an official of the Japan Nuclear and Industrial Safety Agency told a news conference"[13]. "This is of particular concern since, unlike all of the other reactors in trouble, Unit 3 has been using plutonium-based MOX (mixed oxide) fuel since September 10, 2010. Consequences of an accident at a MOX-powered reactor would be even more severe than at a more typical uranium-powered reactor", says the Nuclear Information and Resource Service[14] On March 13 the chief Cabinet secretary of Japan's government informed that an explosion at unit 3 of Fukushima 1 is possible to occur, but that they wouldn't expect a meltdown to happen[15][16] (however they want to be sure about that after the last days' experiences...). Several attempts to cool the reactor core failed until the late evening of Sunday[2], it eventually exploded Monday morning at 2.01 AM GMT[17][18]. NIRS believes there are now multiple meltdowns in progress along with significant releases from irradiated fuel pools[14].

Status of the affected facilities

  • Fukushima 1 unit 1: The water level is such low that measurement instruments couldn't be recorded clearly anymore as the Japanese nuclear authority NISA found out (18/3/11)[19]
    • The outer building is damaged and it is presumed that there was a partial meltdown. At least small amounts of radioactivity have been vented (16/3/11)[20]
  • Fukushima 1 unit 2: 1.4 m of the fuel rods are exposed (17/3/11 11 PM GMT)[19]
    • primary containment is believed to be significantly breached (16/3/11 2 PM GMT)[14]
    • there has been an explosion; there is speculation that this explosion has damaged the primary containment(14/3/11)[14]
    • fears of a partial meltdown as the fuel elements were several times totally exposed and thus cooling failed (14/3/11)[7]
    • no cooling capability anymore (12/3/11)[14]
  • Fukushima 1 unit 3: the condition of the fuel pools appears to remain more serious (19/3/11 2.30 PM GMT)[14]
    • 2.3 m of the fuel rods are exposed (17/3/11 11 PM GMT)[19]
    • the fuel pool might also be losing water and could soon be in the same condition as at unit 4 (16/3/2011)[21]
  • Fukushima 1 unit 4: the condition of the fuel pools appears to remain more serious (19/3/11 2.30 PM GMT)[14]
    • US NRC Chairman Greg Jazcko told a Congressional committee this afternoon that the Unit 4 fuel pool has no water and is releasing massive amounts of radiation (16/3/11 8.30 PM GMT)[14]; commission representatives in Tokyo and TEPCO confirmed that the pool at No. 4 was empty (18/3/11)[21][19]; NRC people were on the site saying that the fuel pool is without water and that the released radiation is lethal in a short period of time (17/3/11 9 PM GMT)[14]
    • flames appeared; it is impossible to go near the fire since the radiation is so high (15/3/11 8.45 PM GMT)[14]
    • There was briefly a fire in the irradiated fuel pool - it is said to be extinguished for now (15/3/11 12.15 PM GMT)[14]
  • Fukushima 1 unit 5: TEPCO has cut holes in the roofs of the containment building in an effort to remove building pressure and prevent explosions such as those that severely damaged Units 1, 3 and 4. This means some radiation is certainly being released through these holes (19/3/11 2.30 PM GMT)[14]
    • offcials said they had experienced a slight rise in temperature, while the operator says the emergency power supplies have been restored (18/3/11)[21][19]
  • Fukushima 1 unit 6: TEPCO has cut holes in the roofs of the containment building in an effort to remove building pressure and prevent explosions such as those that severely damaged Units 1, 3 and 4. This means some radiation is certainly being released through these holes (19/3/11 2.30 PM GMT)[14]
    • offcials said they had experienced a slight rise in temperature, while the operator says the emergency power supplies have been restored (18/3/11)[21][19]

Connected additional accidents in other atomic facilities

Several other nuclear Japanese facilities are faced to serious safety issues as a result of the tsunami and earthquakes: the reprocessing unit Rokkasho (difficulties with cooling systems), the NPP Fukushima 2 Daini (fire, failing cooling systems - atomic power emergency declared), the NPP Tokai (two of three emergency power generators failed) and the NPP Onagawa (fire, leakage - atomic power emergency declared)[9][2].

Health impacts of the catastrophe

One worker died as a result of the explosion of Fukushima 1 unit 1, three others were injured and sent to hospital. A contractor had been found unconscious and two workers of a "cooperative firm" had been injured. At unit 3 one worker received a high radiation dose, and the whereabout of two workers remained unknown.[22] "Fukushima Prefecture revealed that there are an additional 19 individuals who have received radiation doses. This brings the total to 22 people. According the METI’s NISA, there is a possibility that 160 individuals living in the vicinity of the nuclear power plants have received radiation doses", Mainichi reported on Sunday March 13[23]. While Japanese authorities as well as an IAEA spokesman and recently also some BBC correspondents were downplaying the risks of the radiation released, the legal exposure limit for the workers was raised on Wednesday from 100 to 250 millisieverts in Japan[7]. Meanwhile the operator of the crashed NPPs TEPCO and the Japanese authorities are considering a Chernobyl-like sarcophagus solution as a last means for the damaged reactors[19]. By Thursday March 17, the available data about radiation from Fukushima I show releases of already "about a tenth of what was released from the Chernobyl-4 reactor in Ukraine in 1986", experts of the French IRSN (Institute of Radiological Protection and Nuclear Safety) informed.[24] On Saturday March 19 the Japanese government confirmed high radiation in spinach and milk near the nuclear power plant[25]. The spinach was growing some 60 kilometers from the site[14]. Vegetables from the Fukushima region and the also radioactively affected Ibaraki area south of Fukushima are still going to be sold in Tokyo, the New York Times reported[25].

Assumptions about weather impacts by NIRS: At this point, the wind is a huge factor. So far (17/3/11), it is continuing to blow east away from the land and toward the Pacific Ocean. A shift in the wind could have severe consequences. Most alarming are reports from AccuWeather and CNN that wind directions—which through the week have been steadily west-east toward the Pacific Ocean—are shifting: first to the north and northwest, then on Monday (March 21) south toward Tokyo.[14]

Causes of the disaster

What happened in detail in Fukushima is yet unclear as the authorities and the operator publish hardly any concrete information, and probably by now no one knows exactly how the reactors look inside to examine the happenings before the explosions occured. However, there are hypotheses about the causes of the accident. The major interpretation reads as following: When the earthquakes happened, the units 1-3 of Fukushima I Daiichi were shut-down automatically while the reactors 4-6 were already offline due to regular maintenance. These earthquakes also caused the huge tsunami reaching up to 10 meters height. The tsunami surmounted the protection walls that were thought to stop normal tsunamis and hit the emergency power generators of the units. They still worked for a certain time before they failed. When the cooling systems stopped working hydrogen was generated under the conditions of hot steam and high pressure. Due to the nitrogen concentration in the reactor core it could not ignite inside the containment. To reduce the pressure and to prevent an explosion the operator opened the containment to release some steam (and simultaneous to release radiation to the environment). Shortly afterwards unit 1 exploded due to the hydrogen catching fire in the nitrogen poor reactor building. This happened in other units later, too.

On March 20, Nuclear Power Daily uncovered TEPCO to have lied about their safety procedures: "We can't say that the lapses listed in the (February 28) report did not have an influence on the chain of events leading to this crisis", a nuclear safety agency official said. TEPCO had admitted a couple of days before the catastrophe that they had faked reparing records. For several years wrong statements about inspections and results had been made by TEPCO including parts of cooling systems like water pump motors and diesel generators.[26]

Reactions in other countries

While experts yet discuss the impacts of the nuclear catastrophe, the German atomic lobbying organization "Deutsches Atomforum" insisted a similar accident could not happen at German nuclear power plants as their safety systems would be prepared to deal with those situations (the same the Japanese nuclear industry said about their reactors by now)[27]. Meanwhile Japan’s Nuclear and Industrial Safety Agency (NISA) said March 12 that the explosion at the Fukushima Daiichi No. 1 nuclear plant could only have been caused by a meltdown of the reactor core[28]. Under public pressure and on view of several elections during the next weeks the German government decided the temporary shut-down of seven German NPPs for some 3 months[29].

As a result of the massive protests in Germany the German government had to announce a moratorium of three months of interruption[30] of operation for the seven oldest and most dangerous nuclear reactors: Neckarwestheim-1, Philippsburg-1, Isar-1, Biblis-A, Unterweser, Biblis-B, Krümmel and Brunsbüttel have been shut-down now[31]. Also some federal states are considering to force the atomic industry to shut down some of their reactors - for instance the Neckarwestheim-1 NPP will be closed permantly[30]. Basically all German NPP will be subject of safety checks during the next months, the government decided[32]. In contrast to this decision Chancellor had stated in direct reaction to the catastrophe in Japan that the German reactors would be safe and that there wouldn't be any reason for concerns.

Since March 12, 2011 vigiles, rallies, blockades[33] of nuclear facilities and other actions[34] are happening around the world to demand an immediate global shut-down of all atomic facilities. In Germany two days after the first explosions about 110,000 people protested in more than 450 vigiles[35], for March 21 - one week later - about 600 vigiles have been announced to take place. On Saturday March 19 some 10,000 protested in Hannover against atomic power[36] and 2,000 people demonstrated their opposition to nuclear power in Hamburg. Mass demonstrations have been called out for March 26 in Berlin, Cologne, Hamburg and Munich. A blockade of nuclear power plants was announced by X-tausend mal quer" for June - when the moratorium of the seven oldest reactors in Germany (they have been tuned off for three months after Fukushima) will end. People are already publicly announcing their participation in theses sit-in blockades or their solidarity with the action.

The Nuclear information and resource service provides an updated factsheet about the catastrophe of Fukushima 1.

  1. 1.0 1.1 as at March 12, 2011
  2. 2.0 2.1 2.2 2.3 as at March 12, 2011
  3. as at March 12, 2011
  4. as at March 14, 2011
  5. as at March 14, 2011
  6. as at March 14, 2011
  7. 7.0 7.1 7.2 7.3 as at March 12, 2011
  8. 8.0 8.1 8.2 8.3 as at March 15, 2011
  9. 9.0 9.1 as at March 12, 2011
  10. as at March 12, 2011
  11.,,83389_cid_14917321,00.html?maca=de-aa-news-855-rdf as at March 16, 2011
  12. as at March 14, 2011
  13. as at March 12, 2011
  14. 14.00 14.01 14.02 14.03 14.04 14.05 14.06 14.07 14.08 14.09 14.10 14.11 14.12 14.13 14.14 as at March 13, 2011
  15. as at March 13, 2011
  16. as at Sunday March 13, 2011
  17. as at March 14, 2011
  18. as at March 14, 2011
  19. 19.0 19.1 19.2 19.3 19.4 19.5 19.6,1518,751682,00.html as at March 18, 2011
  20. as at March 17, 2011
  21. 21.0 21.1 21.2 21.3 as at March 17, 2011
  22. as at March 12, 2011
  23. as at March 13, 2011 via as at March 13, 2011
  24. as at March 19, 2011
  25. 25.0 25.1 as at March 19, 2011
  26. as at March 21, 2011
  27. as at March 12, 2011
  28. as at March 13, 2011
  29. as at March 17, 2011
  30. 30.0 30.1,1518,751078,00.html as at March 21, 2011
  31. as at March 21, 2011
  32. as at March 21
  33. as at March 21, 2011
  34. as at March 21, 2011
  35. as at March 21, 2011
  36. as at March 21, 2011
  37. as at March 17, 2011