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Kerncentrale Japan explodeert.

1. voda 28 augustus 2015 16:09

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   Natural gas market turning in buyers' favour - Report
   
   Forbes reported that following the Fukushima disaster in Japan came the country’s nuclear switch-off in 2011. Away from the unfolding environmental tragedy, one of Asia’s biggest energy consumers had its main utilities providers scrambling for natural gas as a medium term power generation alternative.
   
   That same year, the International Energy Agency had queried if we were entering a ‘Golden Age’ of gas. Much to the chagrin of renewable energy enthusiasts, natural gas usage kicked into high gear at the expense of both nuclear and coal fired power generation. The panic buying that followed in Japan saw many energy providers evoke emergency clauses to ensure the lights were kept on at a premium.
   
   In fact, buying reached such a level that some Japanese players overcommited on procurement. Most long term contracts around the time were linked to the JCC Index, or Japan Customs-cleared Crude, nick-named by regional traders as the ‘Japanese Crude cocktail’. It served to make gas prices in Japan higher, and by extension South Korea and Taiwan suffered from the premium too.
   
   While it was painful at the time, overcommitment on gas procurement means regional utilities find themselves in a strong position to demand price negotiations on contracts that are not heavily predicated on the JCC and actually put out to competitive tender as gas prices fall.
   
   From Asian contract prices in the region of USD 12 to USD 14/MMBtu back then, the most recent spot market prices were lurking around USD 7.95/MMBtu, having plummeted to as low as USD 6.65/MMBtu in May; the lowest level in almost five years according to Platts.
   
   The early August lurch towards USD 8/MMBtu in Asia was only caused by Royal Dutch Shell declaring force majeure on gas supplies to Nigeria’s liquefied natural gas export terminal on Bonny Island in Rivers State due to a pipeline leak. Prior to that, gas prices were falling and reversion to a lower Asian norm is all but inevitable.
   
   Source : Forbes
   

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2. voda 17 september 2015 20:33

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   Japanner vangt monstervis bij kerncentrale Fukushima
   
   Hirasaka Hiroshi, een Japanse visser, heeft een wel heel angstaanjagend exemplaar aan de haak geslagen. Hij ving een monstervis vlakbij de plek waar op 11 maart 2011 een nucleaire ramp plaatsvond in de Fukushima kerncentrale. In de centrale ging het helemaal mis na een zeebeving en een tsunami die daarop volgde. Wetenschappers vermoeden dat de vis door straling zo'n merkwaardig uiterlijk kreeg.
   
   De vis met zijn gigantische, gapende mond lijkt regelrecht weggezwommen uit een prehistorische of dinofilm. Volgens Hiroshi, die zijn vangst trots op Twitter toonde, gaat het om een wolfsvis, ook wel zeewolf genoemd. Normaalgesproken worden die gemiddeld zo'n meter lang, maar het exemplaar van de Japanse visser is bijna twee keer zo groot.
   
   Hiroshi vindt zijn vis 'supercool' en meldt dat hij blij is dat hij de vlucht naar Hokkaido, dat zo'n 800 kilometer van Fukushima ligt, maakte om vlakbij de centrale te gaan vissen. Wolfsvissen zwemmen nooit dicht bij het wateroppervlak en laten zich slechts in uitzonderlijke gevallen vangen met een doorsnee hengel. Ze leven onder normale omstandigheden altijd op de zeebodem.
   
   Eerder werden bij Fukushima gemuteerde madeliefjes aangetroffen. Het was volgens deskundigen echter niet zeker dat er een link met de radioactieve straling is. Het ging waarschijnlijk om een 'gewone' mutatie die fasciatie genoemd wordt.
   
   Voor afbeelding, zie link:
   
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3. voda 29 februari 2016 13:43

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   Managers kerncentrale Fukushima aangeklaagd
   
   Door: redactie
   29-2-16 - 13:16 bron: ANP
   
   Vijf jaar na de ramp met de kerncentrale in het Japanse Fukushima zijn drie managers van het verantwoordelijke Tepcoconcern formeel aangeklaagd. De president en twee van zijn vice-presidenten van Tepco wordt verweten dat zij de centrale niet hadden beschermd tegen de tsunami die het gebied op 11 maart 2011 na een zeebeving trof. Dat hebben de Japanse autoriteiten maandag bekendgemaakt.
   
   Door de gevolgen van de tsunami vond een zogenoemde kernsmelting plaats, waardoor uiteindelijk straling vrijkwam. Tepco informeerde de bevolking in het gebied veel te laat over de straling. Hoe het er momenteel in de afgesloten reactorkamers van Fukushma uitziet, weet ook vijf jaar na dato niemand.
   
   Juist maandag werd een andere reactor in Japan na problemen stilgelegd. De kernreactor in Takahama, 400 kilometer ten westen van de hoofdstad Tokio, had problemen met een generator en kwam daardoor automatisch tot stilstand. Volgens de leiding van de reactor is dat proces veilig verlopen.
   
   Naar aanleiding van de ramp met de reactor in Fukushima werden gedurende twee jaar alle 48 kerncentrales in Japan stilgelegd.
   
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4. voda 16 maart 2016 13:57

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   Nuclear power in Japan post Fukushima
   
   The Hindu reported that when the Fukushima accident occurred on March 11, 2011, Japan had 50+ nuclear power reactors which provided about 30 per cent of the country’s electricity. The World Nuclear Association (WNA) noted that this was expected to increase to at least 40 per cent by 2017. The devastating accident changed all that. Japan shut down all its reactors.
   
   As on December 2015, Japan has 43 operable reactors with potential to restart; twenty-three of them have started the process to restart approvals. The first two restarted in August 2015 (Sandai 1) and October 2015(Sandai 2).
   
   While Japan observes the fifth anniversary of the nuclear accident, there is slow and steady progress in examining whether some more of the nuclear power plants which are presently shut down comply with the new nuclear safety standards.
   
   The Nuclear Regulatory Authority effectively approved on February 24, Takahama-1 and two other nuclear power plants — both of which have already been operated for more than 40 years — as compatible with the new regulatory standards.
   
   The Japan Atomic Industrial Forum reports that these are the first such determinations for so-called aging reactors. They have to clear examinations and to get approvals for extensions of their operating lifetimes, for which the mandatory deadlines are in July.
   
   On February 26, this year the Kansai Electric Power Co restarted its Takahama 4 (870MWe) nuclear power plant and Takahama 3 (870MWe) which they restarted on January 29 was returned to commercial service.
   
   Industry and the ruling political class favour restart as they consider nuclear power as reliable, affordable and essential to ensure Japan's energy security.
   
   Japan now constructs four reactors and decommissions or is set to decommission 15. It has planned (9) and proposed (4) new reactors with a total capacity of 17,092 MWe
   
   In June 2014, three major lobbies of hard-nosed business men — the Japan Business Federation (Keidanren), the Japan Chamber of Commerce and Industry, and the Japan Association of Corporate Executives (Keizai Doyukai) — sought an early restart of all nuclear reactors.
   
   The stark reality is that over 90 per cent of Japan’s primary energy needs are now met by import.
   
   In 2010, Japan’s per capita annual power consumption stood at 7870 kWh dropping to 7480 kWh/capita in 2013. Though all nuclear power plants were shut down, the Japanese continued to lead an energy intensive life!
   
   On May 11, 2015, four years after the Fukushima nuclear accident, The Japan Times reported that a panel of nuclear experts largely approved a government report saying that atomic power remains the cheapest source of electricity despite the rising safety costs triggered by the 2011 Fukushima core meltdowns. Though the Government expects a glut in solar power, it wants to make nuclear power account for 20 to 22 per cent of Japan’s electricity supply by 2030.
   
   The daily reported that the Japanese Ministry of Economy, Trade and Industry (METI), estimates that atomic power would cost at least ¥10.3 per kilowatt-hour in 2030.
   
   The daily quoted METI as saying that additional safety measures required to run a nuclear reactor would cost an average of ¥60.1 billion. The report estimates that the cost of coal-fired power is ¥12.9 per kWh; liquefied natural gas ¥13.4 per kWh; Wind power ¥34.7; solar power up to ¥16.4, geothermal power ¥16.8, and hydropower up to ¥27.1 per kWh, all of them much higher than nuclear.
   
   The cost of electricity estimated by the Institute of Energy Economics of Japan in 2011 included compensation of up to ¥10 trillion ($130 billion) for loss or damage from a nuclear accident (WNA, Dec 2015), ¥0.2 for additional post-Fukushima safety measures and ¥0.5 for dealing with future nuclear risks. The ¥0.5 for future nuclear risks is a minimum, increasing by ¥0.1 for each additional ¥1 trillion ($13 billion) of damage.
   
   The public perception in Japan may be against nuclear power. But in December 2012, the pronuclear Liberal Democratic Party (LDP) got 294 out of 480 seats with the anti nuclear group trailing behind with 57 seats in the lower house of Diet. The LDP and its pronuclear partner secured 144 seats in 242 in the upper house in the July 2013 election.
   
   The Japanese Government pledged to reduce reliance on nuclear power and promote renewable energy as much as possible, while standing by nuclear as a key power source, citing the importance of a stable electricity supply to economic growth. Because of its economic importance, decision makers will benignly look at nuclear power.
   
   Source : The Hindu
5. voda 8 februari 2017 19:13

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   Record radiation level detected inside damaged Fukushima reactor
   
   The plant operator said that a record radiation level has been detected inside the No. 2 reactor at the damaged Fukushima Daiichi nuclear complex, with the estimated reading of up to 530 sieverts per hour.
   
   The reading means a person could die from even brief exposure, highlighting the difficulties ahead as the government and Tokyo Electric Power Company Holdings Inc grope their way toward dismantling all three reactors that melted down in the March 2011 nuclear disaster.
   
   The plant operator also announced that based on an image analysis, a 1-square-meter hole has been found on a metal grating beneath the reactor pressure vessel, likely caused by melted nuclear fuel that fell through the vessel.
   
   The new radiation level, described by some experts as “unimaginable,” far exceeds 73 sieverts per hour, the previously highest radiation reading monitored in the interior of the reactor.
   
   An official of the National Institute of Radiological Sciences said medical professionals have never considered dealing with this level of radiation in their work.
   
   According to TEPCO, the extremely high radiation level was detected inside the containment vessel, in the space around 2.3 meters away from the base of the reactor pressure vessel.
   
   According to the institute, 4 sieverts of radiation exposure would kill one in two people.
   
   Experts said that 1,000 millisieverts, which equals 1 sievert, could lead to infertility, loss of hair and cataracts, while exposure to radiation doses above 100 sieverts increases the risk of cancer.
   
   The latest discovery spells difficulty in removing the fuel debris as part of decommissioning work at the plant. The government and TEPCO hope to locate the fuel and start removing it from a first reactor in 2021.
   
   The debris is believed to have been created as nuclear fuel inside the reactor pressure vessel overheated and melted due to the loss of reactor cooling functions.
   
   In the coming weeks, the plant operator plans to deploy a remote-controlled robot to check conditions inside the containment vessel, but the utility is likely to have to change its plan.
   
   For one thing, it will have to reconsider the route the robot is to take to probe the interior because of the hole found on the grating.
   
   Also, given the extraordinary level of radiation inside the containment vessel, the robot would only be able to operate for less than two hours before it is destroyed.
   
   Source : Japan Today

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6. voda 17 februari 2017 16:10

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   Robot sent to clean Fukushima nuclear reactor dies because of excessive radiation in Japan - Report
   
   Tech Times reported that a remote-controlled cleaning robot sent to clear a passage for another robot at the Fukushima nuclear power plant in Japan met its demise after briefly being exposed to excessive radiation.
   
   After two hours of laboring to clear grime, it started emitting strange noises while its camera began to malfunction before finally going dark. It had to be hastily pulled out before operators finally lose complete control. The machine expired shortly afterward.
   
   The cleaning robot is part of a larger mission to explore and measure the radiation level at the reactor after its meltdown in 2011. The facility was affected by a tsunami, which destroyed the emergency generators used to cool the reactors.
   
   The recent foray into reactor No. 2 is effectively the first attempt to enter the contaminated facility after the incident. The exploratory mission is expected to provide insights so Japanese authorities can ensure that radiation is contained within the facility.
   
   Now, one should note that the robots used in the facility are built to withstand 1,000 accumulated sieverts. This is the reason why officials of the Tokyo Electric Power Company Holding are now scrambling after what happened to the cleaning machine.
   
   Several days ago, it was indicated that the radiation level at the reactor No. 2 has already reached 520 sieverts per hour. This number is already off the charts, enough to kill a human within seconds of exposure. Considering the radiation tolerance of the robots, however, officials recognized that something was wrong with the initial figure.
   
   Indeed, TEPCO has already revised the estimated radiation level, increasing the number to 650 sieverts. The 120-level discrepancy is quite disturbing and seems to validate criticism that its radiation measurement method is unreliable.
   
   Some Japanese government representatives have already expressed reservations that TEPCO has been drawing information from the interference in the camera outfitted in the robots being sent to investigate. A Geiger counter measurement is seen as a better approach.
   
   If TEPCO’s measurement is valid, however, another theory is that the cleaning robot, which came armed with a water pump and a scraper, got too close to the source of radiation.
   
   Nevertheless, TEPCO is now in a bind. The death of the first robot not only put the second robot at risk of failing its own mission because of the clogged passageway; this has also cast doubt on the viability of using robots for TEPCO’s investigation.
   
   The recent unfortunate event at the Fukushima nuclear facility does not indicate any immediate threat to surrounding communities although reports reveal that Fukushima radiation has already been detected in U.S. shores. Officials maintain that radiation is contained within the facility and officials are working to guarantee that it remains that way.
   
   Source : Tech Times

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7. voda 25 juli 2017 20:10

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   Possible melted nuclear fuel found inside reactor - Fukushima
   Published on Tue, 25 Jul 2017
   
   DW reported that large amounts of solidified, lava-like, rocks in layers as much as 3 feet (1 meter) thick were seen under Fukushima's Unit 3 reactor, according to Tokyo Electric Power Co., which operates the plant. "It's natural to think that melted material flowed out from the reactor pressure vessel," a company official told a news conference. Three of the plant's four reactors were completely destroyed in 2011 by an earthquake-triggered tsunami that slammed into the waterfront power station. The fourth reactor was also badly damaged.
   
   The 30-centimeter-long remote-controlled robot, which is equipped with two cameras made the discovery on Friday, during the second day of its three-day probe of Unit 3.
   
   Images from the robotic probe showed extensive damage to the unit caused by the core meltdown. Fuel debris was seen mixed together with broken reactor parts, suggesting that the decades-long decommissioning process that lies ahead will be difficult.
   
   TEPCO spokesman Takahiro Kimoto said more time is needed to fully analyze the images to figure out how to remove the debris. Almost 6.5 meters (21 feet) of water has accumulated at the bottom of the containment vessel, as the operator continues to inject water into the unit to cool the fuel.
   
   Locating and analyzing the fuel debris and damage in each of the plant's three destroyed reactors is critical for decommissioning the plant. So far the search for melted fuel in the other two reactors has been unsuccessful because of damage and extremely high radiation levels.
   
   Source : DW

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8. voda 9 oktober 2017 16:50

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   Radioactive waste found 60 miles away from Fukushima Meltdown site in Japan
   Published on Mon, 09 Oct 2017
   
   According to new research published, radioactive material left over from the 2011 Fukushima nuclear disaster in Japan has traveled 60 miles away from the meltdown site. The disaster occurred after a devastating earthquake and tsunami disabled the emergency generators that cooled the Fukushima Daiichi nuclear power station's spent nuclear fuel rods. The research, published in Proceedings of the National Academy of Sciences, shows that a radioactive isotope of cesium (cesium-137), which is generated through nuclear fission and can be lethal to humans in high concentrations, collected in the sands and groundwater along the 60-mile Pacific coastline near the plant.
   
   The study abstract explains "During our study period, we found the highest cesium-137 levels outside of the nuclear site not in the ocean, rivers or potable groundwater, but in groundwater beneath sand beaches over tens of kilometers away from the nuclear site."
   
   According to lead researchers Virginie Sanial of Woods Hole Oceanographic Institution and Seiya Nagao of Kanazawa University, the concentrations of radiation found "are not of primary concern." However, they do shed light on leaking radiation and "should be taken into account in the management of coastal areas where nuclear power plants are situated."
   
   To reach their conclusions, the researchers obtained samples between 2013 and 2016 from eight different beaches that were all within 60 miles of the facility. They used seven-foot-long tubes to extract sand and groundwater samples, which they then analyzed for cesium levels. The cesium levels in brackish groundwater were 10 times higher than levels in water near the plant's harbor.
   
   The researchers predict that the radioactive material was carried along the coast by ocean currents. Over time, cesium stuck to the sand gradually filtered to the brackish groundwater found in the cracks and spaces in sand, soil and rock. Sanial's team estimates that the radioactive material is now currently being released by the groundwater into the coastal ocean at a rate that is similar to the leakage rate of cesium into the ocean from the plant site.
   
   With half of the world's nuclear reactors situated along the coastline, the tracking of radioactive material so far from the meltdown source can help improve nuclear power plant monitoring and accidents, according to the study's researchers.
   
   Source : Sputnik

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9. voda 4 maart 2018 17:14

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   New evidence of nuclear fuel releases found at Fukushima
   
   Uranium and other radioactive materials, such as caesium and technetium, have been found in tiny particles released from the damaged Fukushima Daiichi nuclear reactors. This could mean the environmental impact from the fallout may last much longer than previously expected according to a new study by a team of international researchers, including scientists from The University of Manchester.
   
   The team said that for the first time, the fallout of Fukushima Daiichi nuclear reactor fuel debris into the surrounding environment has been “explicitly revealed” by the study.
   
   The scientists have been looking at extremely small pieces of debris, known as micro-particles, which were released into the environment during the initial disaster in 2011. The researchers discovered uranium from nuclear fuel embedded in or associated with caesium-rich micro particles that were emitted from the plant’s reactors during the meltdowns. The particles found measure just five micrometres or less; approximately 20 times smaller than the width of a human hair. The size of the particles means humans could inhale them.
   
   The reactor debris fragments were found inside the nuclear exclusion zone, in paddy soils and at an abandoned aquaculture centre, located several kilometres from the nuclear plant.
   
   It was previously thought that only volatile, gaseous radionuclides such as caesium and iodine were released from the damaged reactors. Now it is becoming clear that small, solid particles were also emitted, and that some of these particles contain very long-lived radionuclides; for example, uranium has a half-life of billions of years.
   
   Dr Gareth Law, Senior Lecturer in Analytical Radiochemistry at the University of Manchester and an author on the paper, said that “Our research strongly suggests there is a need for further detailed investigation on Fukushima fuel debris, inside, and potentially outside the nuclear exclusion zone. Whilst it is extremely difficult to get samples from such an inhospitable environment, further work will enhance our understanding of the long-term behaviour of the fuel debris nano-particles and their impact.”
   
   The Tokyo Electric Power Company is currently responsible for the clean-up and decommissioning process at the Fukushima Daiichi site and in the surrounding exclusion zone. Dr Satoshi Utsunomiya, Associate Professor at Kyushu University (Japan) led the study.
   
   He added that “Having better knowledge of the released microparticles is also vitally important as it provides much needed data on the status of the melted nuclear fuels in the damaged reactors. This will provide extremely useful information for TEPCO’s decommissioning strategy.”
   
   At present, chemical data on the fuel debris located within the damaged nuclear reactors is impossible to get due to the high levels of radiation. The microparticles found by the international team of researchers will provide vital clues on the decommissioning challenges that lie ahead.
   
   Source : Strategic Research Institute
10. voda 5 maart 2018 19:33

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    Fukushima radiation levels dangerously high – Report
    
    Economic Times reported that Tokyo, Greenpeace said that its towns in Fukushima prefecture, close to the disaster hit nuclear power plant, were exposed to excessive levels of radiation almost 100 times greater than safe levels. The survey said that in the towns of Namie and Iitate, located between 10 and 40 km from the Fukushima Daiichi plant and where evacuation orders were partially lifted in March 2017, radiation levels continue to be "up to 100 times higher than the international limit for public exposure."
    
    Jan Vande Putte with Greenpeace Belgium, and leader of a survey conducted in the area, said that "This is public land. Citizens, including children and pregnant women returning to their contaminated homes, are at risk of receiving radiation doses equivalent to one chest X-ray every week. This is unacceptable and a clear violation of their human rights.”
    
    The report also warned that all areas surveyed, including those where people have been allowed to return, had levels of radiation similar to an active nuclear facility.
    
    The non-governmental environmental organization said the situation is "requiring strict controls".
    
    Efe news reported that this was despite the fact that residents had lifted restrictions on access after years of decontamination efforts.
    
    Japanese authorities have said these areas are progressively returning to normalcy after the massive 9.1-magnitude earthquake and resulting tsunami which struck on March 11, 2011, triggering the nuclear disaster at Fukushima.
    
    The government had said that radiation levels in the reopened zones pose no risk to human health.
    Japan also noted that the government data was corroborated by the country's medical experts and organizations such as the UN Scientific Committee on the Effects of Atomic Radiation.
    
    Source : Economic Times
11. haas 11 maart 2018 18:14

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    7 jaren geleden/7 jaren verder
12. [verwijderd] 1 april 2018 19:00

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    Gebed zonder einde.
    Maar gelukkig is het geen interessant nieuws meer.
    
    (cynisch)
13. voda 28 mei 2018 19:51

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    Fukushima radioactive particle release was significant – Research
    
    Scientists said there was a significant release of radioactive particles during the Fukushima-Daiichi nuclear accident. The researchers identified the contamination using a new method and say if the particles are inhaled they could pose long-term health risks to humans. The new method allows scientists to quickly count the number of caesium-rich micro-particles in Fukushima soils and quantify the amount of radioactivity associated with these particles.
    
    The research, which was carried out by scientists from Kyushu University, Japan, and The University of Manchester, UK, was published in Environmental Science and Technology.
    
    In the immediate aftermath of the Fukushima Daiichi nuclear accident, it was thought that only volatile, gaseous radionuclides, such as caesium and iodine, were released from the damaged reactors. However, in recent years it has become apparent that small radioactive particles, termed caesium-rich micro-particles, were also released. Scientists have shown that these particles are mainly made of glass, and that they contain significant amounts of radioactive caesium, as well as smaller amounts of other radioisotopes, such as uranium and technetium.
    
    The abundance of these micro-particles in Japanese soils and sediments, and their environmental impact is poorly understood. But the particles are very small and do not dissolve easily, meaning they could pose long-term health risks to humans if inhaled.
    
    Therefore, scientists need to understand how many of the micro-particles are present in Fukushima soils and how much of the soil radioactivity can be attributed to the particles. Until recently, these measurements have proven challenging.
    
    The new method makes use of a technique that is readily available in most Radiochemistry Laboratories called Autoradiography. In the method, an imaging plate is placed over contaminated soil samples covered with a plastic wrap, and the radioactive decay from the soil is recorded as an image on the plate. The image from plate is then read onto a computer.
    
    The scientists said that radioactive decay from the caesium-rich micro particles can be differentiated from other forms of caesium contamination in the soil.
    
    The scientists tested the new method on rice paddy soil samples retrieved from different locations within the Fukushima prefecture. The samples were taken close to (4 km) and far away (40 km) from the damaged nuclear reactors. The new method found caesium-rich micro-particles in all of the samples and showed that the amount of caesium associated with the micro-particles in the soil was much larger than expected.
    
    Dr Satoshi Utsunomiya, Associate Professor at Kyushu University, Japan, and the lead author of the study says “when we first started to find caesium-rich micro-particles in Fukushima soil samples, we thought they would turn out to be relatively rare. Now, using this method, we find there are lots of caesium-rich microparticles in exclusion zone soils and also in the soils collected from outside of the exclusion zone”.
    
    Dr Gareth Law, Senior Lecturer in Analytical Radiochemistry at the University of Manchester and an author on the paper, added that “Our research indicates that significant amounts of caesium were released from the Fukushima Daiichi reactors in particle form. This particle form of caesium behaves differently to the other, more soluble forms of caesium in the environment. We now need to push forward and better understand if caesium micro-particles are abundant throughout not only the exclusion zone, but also elsewhere in the Fukushima prefecture; then we can start to gauge their impact.”
    
    The new method can be easily used by other research teams investigating the environmental impact of the Fukushima Daiichi accident.
    
    Dr Utsunomiya added that “We hope that our method will allow scientists to quickly measure the abundance of caesium-rich micro-particles at other locations and estimate the amount of caesium radioactivity associated with the particles. This information can then inform cost effective, safe management and clean-up of soils contaminated by the nuclear accident.”
    
    Source : Strategic Research Institute

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14. voda 15 oktober 2018 19:45

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    Fukushima nuclear plant owner apologises for still-radioactive water
    
    Reuters reported that Fukushima nuclear plant owner apologises for still-radioactive water The owner of the Fukushima nuclear plant, destroyed by an earthquake and tsunami more than seven years ago, said water treated at the site still contains radioactive materials that for years it has insisted had been removed. The admission by Tokyo Electric Power (Tepco) could ruin its chances of releasing the water into the ocean, a move the nuclear regulator says is safe but which local fishermen oppose.
    
    Tokyo won the bid to host the 2020 Summer Olympics more than five years ago, with Prime Minister Shinzo Abe declaring that Fukushima was "under control" in his final pitch to the International Olympic Committee.
    
    The nearly one million tonnes of stored water at the wrecked plant, enough to fill about 500 Olympic swimming pools, still contained detectable levels of potentially harmful radioactive particles, Tepco told a government committee on October 1.
    
    Tepco 9501.T apologised to the committee under the Ministry of Economy, Trade and Industry, which is looking into ways to dispose of the water.
    
    A spokesman at Tepco confirmed the findings and the apology.
    
    Source : Reuters
15. voda 31 december 2018 16:29

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    Jail term demanded for ex-bosses over Fukushima nuclear crisis
    
    Straits Times reported that a five year jail term was sought for three former executives at the company operating Japan's Fukushima nuclear plant, media reported Wednesday, the only people to face criminal charges over the 2011 meltdowns. Former chairman of Tokyo Electric Power Tsunehisa Katsumata and former vice presidents Sakae Muto and Ichiro Takekuro are charged with professional negligence resulting in death and injury, and have pleaded not guilty.
    
    They are the only charges to have stemmed from the tsunami-sparked reactor meltdowns at the plant that set off the worst atomic crisis since Chernobyl in 1986.
    
    Attorneys, who are exceptionally acting as prosecutors in the trial, said the three executives were aware of data indicating the nuclear plant risked being hit by a tsunami with waves exceeding 15 metres enough to trigger power loss and cause severe accidents.
    
    "They should have halted operations at the nuclear plant" until the company finished anti-tsunami measures, including construction of a breakwater, the prosecutors told Tokyo District Court, according to Jiji Press.
    
    Katsumata, 78, has said during the trial he could not have predicted the towering waves that pummelled Japan's northeast coast and swamped reactors in March 2011.
    
    The disaster forced tens of thousands to evacuate their homes near the plant. Many are still living in other parts of Japan, unable or unwilling to go back home as fears over radiation persist.
    
    The charges against the ex-bosses are linked to the deaths of more than 40 hospitalised patients who were hastily evacuated from the Fukushima area and later died.
    
    Prosecutors had twice refused to press charges, citing insufficient evidence and little chance of conviction.
    
    But a judicial review panel composed of ordinary citizens ruled in 2015 that the trio should be put on special trial in which designated attorneys accuse defendants and demand a penalty.
    
    Waves as high as 14 metres swamped the reactors' cooling systems in March 2011 after a 9.0 magnitude tremor.
    
    Although the quake-tsunami disaster left some 18,500 people dead or missing, the Fukushima accident itself is not officially recorded as having directly killed anyone.
    
    A parliamentary report a year after the disaster said Fukushima was a man-made crisis caused by Japan's culture of "reflexive obedience".
    
    Source : Straits Times

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16. voda 26 april 2019 16:16

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    Japan to suspend operations at nuclear plants if deadline missed
    
    Xinhua reported that Japan's nuclear watchdog denied requests from power companies to extend deadlines for them to complete steps to install measures to protect against terrorism at their nuclear facilities. The Nuclear Regulation Authority said it would suspend the operations at plants that have not fulfilled anti-terrorism measures instituted in 2013 under stricter operational guidelines after the 2011 Fukushima nuclear crisis. Under the guidelines, the operators of nuclear power plants are required to build facilities to safeguard against terrorist attacks, such as standby control rooms so that reactors can still be controlled remotely even in the event of a plane being flown into a plant.
    
    This is in order to prevent the recurrence of the massive amounts of radioactive material that was released into the air, ground and sea following Tokyo Electric Power Co losing control of key cooling and backup functions at the Fukushima Daichi nuclear facility, leading to core meltdowns in reactors after the plant was hit by an earthquake-triggered tsunami.
    
    The ongoing crisis at the plant remains the worst nuclear crisis in the world since the 1986 Chernobyl disaster.
    
    The operators, under the new post-Fukushima guidelines, were given within five years to make the counter terrorism upgrades after their reactors cleared safety inspections and were brought back online.
    
    But three power companies, Kyushu Electric, Kansai Electric and Shikoku Electric, said they need more time to implement the anti-terrorism changes at the five plants they collectively operate in western and southwestern Japan.
    
    Seven reactors at four of the plants have already cleared the preliminary safety inspections and have been brought back online.
    
    The power companies have said, however, that they will need between one and two-and-a-half years to complete the required upgrades, with the No. 1 reactor of the Sendai power plant in Kagoshima Prefecture facing the earliest suspension if the necessary work is not completed by March 2020.
    
    The NRA has said it will listen to the operators' opinions and evaluate alternative measures the utilities have or will be implementing in terms of defending against possible acts of terrorism.
    
    Source : Xinhua
17. voda 24 juli 2019 17:17

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    TEPCO to Decommission Fukushima Daini Nuclear Plant
    
    Tokyo Electric Power Company Holdings Inc will formally decide to decommission the Fukushima Daini nuclear plant after informing the prefecture's governor of its policy as early as this month. Excluding the nearby Daiichi, crippled by the March 2011 earthquake and tsunami disaster, it is the first time that the utility, also known as TEPCO, has decided to decommission a nuclear plant.
    
    The decommissioning of all four nuclear reactors at Daini will likely require more than 40 years and some 280 billion yen ($2.6 billion) in costs, the source said. If realized, all 10 nuclear reactors in Fukushima Prefecture will be scrapped.
    
    Closure of the Daiichi plant, which suffered core meltdowns at three of its six reactors, has already been decided.
    
    After telling Fukushima Gov. Masao Uchibori about the policy, it may be formally approved at a TEPCO board meeting, scheduled at the end of this month, the source said.
    
    The Daini complex was also hit by tsunami waves in the 2011 disaster and temporarily lost reactor cooling functions. But unlike the Daiichi plant, it escaped meltdowns.
    
    Source : Japan Today
18. voda 30 juli 2019 17:11

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    TEPCO to Scrap Fukushima No 2 Nuclear Plant
    
    Tokyo Electric Power Co Holdings Inc formally announced on July 24 it will decommission the Fukushima No. 2 nuclear power plant, an undertaking it estimates will take more than four decades to complete. The utility estimated the cost of decommissioning the No. 2 plant at 280 billion yen (USD 2.59 billion).
    
    The company president, Tomoaki Kobayakawa, conveyed the decision to Fukushima Governor Masao Uchibori and other senior prefectural officials during a meeting at the prefectural government building here.
    
    TEPCO’s decision followed repeated requests from the prefectural government to scrap the No. 2 plant in light of the triple meltdown at the No. 1 plant triggered by the 2011 earthquake and tsunami disaster.
    
    Kobayakawa explained that the decision to decommission the No. 2 plant was difficult to make and took time because of the slew of factors involved. He said that “It is unprecedented to scrap all six reactors (at the Fukushima No. 1 nuclear plant) as well as the four reactors (at the Fukushima No. 2 nuclear plant). Another consideration was that we need to simultaneously proceed with work to decommission the No. 1 nuclear plant in a safe and steady manner.”
    
    Source : Asahi
19. whammy 10 september 2019 09:56

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    Moeten we hier iets van vinden? en weet iemand hier of tritium ongevaarlijk wordt bij verdunning?
    Het Japanse elektriciteitsbedrijf Tokyo Electric Power (Tepco) zegt noodgedwongen 1 miljoen ton radioactief vervuild water direct in zee te moeten dumpen. Dat heeft het Japanse ministerie voor milieu dinsdag verklaard, zo schrijft persbureau Reuters.
    Tepco zegt nu vanwege ruimtegebrek geen andere mogelijkheid meer te zien dan het water te lozen. 'De enige optie die we hebben is het water te verdunnen en direct in zee te dumpen', aldus de minister van milieu Yoshiaki Harada.
    Al in 2016 heeft Tepco voorgesteld het water grotendeels te ontdoen van radioactief afval. De enige stof die dan rest is tritium, een waterstofisotoop dat zich makkelijk vermengt met water en moeilijk laat scheiden. In zee zou het dan verder verdunnen en volgens Tepco ongevaarlijk worden. Maar experts zijn het oneens over het gevaar van tritium.
    bron:FD
20. voda 12 september 2019 19:12

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    Japan Regulator to Launch New Investigation into Fukushima Disaster
    
    Reuters reported that Japan’s nuclear regulator said that it would launch a new investigation into the Fukushima disaster, to look into how radiation leaked from damaged reactor containment vessels and other factors. Three reactors at an atomic power plant run by Tokyo Electric Power melted down after an earthquake and tsunami eight years ago, spewing radiation that forced 160,000 people to flee, many never to return.Authorities have said they are planning a series of investigations as radiation levels gradually fall enough in reactor buildings to allow closer examination.
    
    The Nuclear Regulation Authority released a paper showing it would look into the leaks in the reactor vessels and at cooling systems set up to keep the melted fuel in the reactors from overheating.
    
    Tokyo Electric Power said it was ready to help. A spokesman said that “If requested in the future, we would like to proactively cooperate in the investigation, such as providing necessary data.”
    
    A commission appointed by Japan’s parliament concluded in 2012 that Fukushima “was a profoundly manmade disaster – that could and should have been foreseen and prevented, (while) its effects could have been mitigated by a more effective human response.”
    
    Source : Reuters