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Tsunami hits north-eastern Japan after massive earthquake, triggering nuclear crisis

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  • #31

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      • #33

        March 12, 2011 -- Several workers at a nuclear plant facing a possible meltdown may have been injured after shaking and smoke was reported, Japanese officials said. It is unclear if an explosion occurred and officials were investigating the cause, Fukushima Prefecture official Masato Abe told the Associated Press. But Tokyo Electric said an explosion happened in the first reactor, according to local media reports. Broadcast images showing the plant show the skeleton of the structure remains. NHK reported at least four people were injured.

        This incident comes as the level of water used to cool a nuclear reactor damaged in Friday's 8.9-magnitude earthquake and tsunami dropped to an alarming level today, according to the Nuclear and Industrial Safety Agency, heightening fears of a larger nuclear disaster. As of 11:20 a.m. local time, a part of the "fuel assembly" of fuel rods at the Fukushima Daiichi plant's No. 1 reactor was exposed above water, with a maximum exposure of about 90 centimeters. If the fuel rods remain exposed, they will be damaged, releasing radioactivity.

        "This is extremely serious," said Joseph Cirincione, president of the Ploughshares Fund and an expert on national security and international policy. "The best case at this point would still be the worst incident since Chernobyl. "We are in uncharted territory," he said. "It is possible that this can be contained and we would have a very bad nuclear contamination event. But if the water levels continue to drop and the rods are exposed further it could lead to a core meltdown. The core would melt through the steel holding structure and plunge in a burning, molten mass into the concrete containment structure. If the structure is sound, it could contain the mass, if it has been structurally damaged, then it, too, could breech and we would have a massive, radioactive release."

        About 27,000 liters of water, including water stored for firefighting, was being pumped into the reactor via makeshift pumps and other means in order to raise the water level above the reactor's nuclear fuel, NISA said. "NISA just confirmed that the fuel may be partially melting," Dr. Tatsujiro Suzuki, vice-chairman of the Japan Atomic Energy Commission told ABC News. "The question is whether the situation is getting worse or not. It is reported that the level of water is declining (bad news) but pressure is also decreasing (good news). So, efforts to contain the event (need water) may be working. It is also stated that the amount of radioactivity is still small so that the general public does not need to be concerned at present." Nevertheless, the government continued to ask everyone around the plant, about 200 miles northeast of Tokyo, to "calmly" evacuate, Japanese broadcaster NHK reported. An evacuation order for a 10-kilometer radius around the plant had been issued earlier.

        The Fukushima Daiichi plant was one of two run by the Tokyo Electric Power Co. whose cooling systems were damaged in the earthquake and tsunami. At least two reactors at the plant and three at the nearby Fukushima Daini plant had damaged cooling systems, the Associated Press reported. There also was an evacuation order in effect for residents living within a mile of the Daini plant. But the situation at the Fukushima Daiichi reactor No. 1 was reported to be the most dire. Radiation inside the reactor surged to 1,000 times its normal level after Friday's earthquake knocked out power to its cooling system, and the tsunami floods have hampered efforts to get it restored. Heat-induced pressure built up inside the crippled reactor after the reactor lost power, automatically shut down and the cooling system failed. The situation at the reactor and the four others with compromised cooling systems prompted officials to declare nuclear emergencies.

        Scientists said that even though the No. 1 reactor at the Fukushima Daiichi site, in particular, had stopped producing energy, its fuel continued to generate heat and needed steady levels of coolant to prevent it from overheating and triggering a dangerous cascade of events. "You have to continue to supply water. If you don't, the fuel will start to overheat and could melt," said Edwin Lyman, a senior staff scientist in the Global Security program at the Union of Concerned Scientists in Washington, D.C. A meltdown could lead to a breach of the reactor's steel containment vessel and allow radiation to escape into an outer, concrete containment building, or even into the environment. "Up to 100 percent of the volatile radioactive Cesium-137 content of the pools could go up in flames and smoke, to blow downwind over large distances," said Kevin Kamps, a nuclear waste specialist at Beyond Nuclear, which is an advocacy group that opposes nuclear weapons and power. "Given the large quantity of irradiated nuclear fuel in the pool, the radioactivity release could be worse than the Chernobyl nuclear reactor catastrophe of 25 years ago."

        The Kyodo News Service reported Friday that some radioactive material already may have escaped, citing reports from the Japanese Nuclear Safety Agency that radiation levels outside the plan have been eight times the normal level. Experts said that level of exposure is not dangerous to the general population. "You've got to take all potential precautions," President Obama told reporters Friday when asked about vulnerability of the Japanese nuclear power facilities. "And I've asked Steve Chu, our energy secretary, to be in close contact with their personnel to provide any assistance that's necessary, but also to make sure that if in fact there have been breaches in the safety system on these nuclear plants, that they're dealt with right away."

        Experts say cooling the reactor's core to minimize pressure inside the containment structure is a top priority. Japanese authorities have been trying to connect diesel-powered generators to restore the water pumps inside the reactor but have been hampered by the floods. "If you have something that generates heat and you don't cool it off or release the steam, you're in trouble," said nuclear consultant Mycle Schneider, who compared the situation to a pressure cooker. The risk is a rapid rise in heat that would leave the core uncovered - something that may have begun Saturday. "If it's not covered with water, it can start melting very quickly," Schneider said.

        Meanwhile, officials performed a controlled release of some slightly radioactive vapor that has been building up inside the containment structure, the Associated Press reported. The release would allow harmful material to escape into the environment, but not at levels as great as if there was a massive containment failure, Lyman said. "It's good they evacuated - let's put it that way," Lyman said. "All indications are that this is a very serious event."

        U.S. nuclear experts say modern power plants are designed to withstand earthquakes and tsunamis and have several security layers in place in the event of lost power, including diesel fuel generators and battery systems. "There are multiple redundancies to continue to feed water to the core to take the heat away at most facilities," said an official with the U.S. Nuclear Regulatory Commission, who asked not to be named because he is not familiar with details of the Fukushima plant. But those back-up power sources may not have worked in this case, a development many international experts called troublesome. "The Japanese are considered the best in the world," said Schneider. "They had several generators in place in case one of them doesn't work. This is the first time I've heard of where none of them worked. To me, that is a very deep concern."

        Other Japanese nuclear plants also appeared compromised by the earthquake and tsunami. Besides the loss of cooling systems at three of four Fukushima Daini reactors, the turbine building at the nearby Onagawa nuclear power plant burst into flames shortly after the earthquake, though it later was extinguished. The International Atomic Energy Agency said it was closely monitoring the situation at the four Japanese nuclear power sites impacted by the earthquake and confirmed that all had been successfully shut down. "It's a positive sign," Mitch Singer of the Nuclear Energy Institute, a U.S. industry trade group, said of initial reports of the power plants' performance and durability following the quake. "This industry more than all others depends on the safe operation of the plant, and it appears these robust facilities have operated as they were designed to do." Japanese nuclear power plants have been tested repeatedly by earthquakes in recent years and operated effectively, according to the World Nuclear Association. Worldwide, 20 percent of nuclear powerplants operate in areas of "significant seismic activity," according to the association.

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        • #34

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          • #35

            VIENNA, March 12, 2011 (Reuters) -- The U.N. nuclear watchdog said it is aware of media reports of an explosion on Saturday at Japan's Fukushima No.1 nuclear power plant and is urgently seeking information from the country's authorities. An official of the International Atomic Energy Agency (IAEA), the Vienna-based U.N. atom body, gave no further details. "We are aware of the media reports and we are urgently seeking further information," the official told Reuters. Jiji news agency said there had been an explosion at the stricken 40-year-old Daichi 1 reactor and TV footage showed vapour rising from the plant, which lies 240 km (150 miles) north of Tokyo.

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            • #36

              March 12, 2011 -- An explosion blew the roof off an unstable reactor north of Tokyo, raising fears of a meltdown at a nuclear plant damaged in the massive earthquake that hit Japan. The 8.9-magnitude earthquake - the strongest ever recorded in Japan - sent a 10-metre tsunami ripping through towns and cities across the northeast coast. Japanese media estimate that at least 1,300 people were killed. Jiji news agency said there had been an explosion at the stricken 40-year-old Daichi 1 reactor and television footage showed vapour rising from the plant, which lies 240 km north of Tokyo. The Tokyo Electric Power Company says that several workers were injured reports Japan's public broadcaster NHK.

              The blast came as plant operator Tokyo Electric Power Co (Tepco) worked desperately to reduce pressures in the core of the reactor that - if not contained - could lead to a release of radiation into the atmosphere. NHK television and Jiji reported that the outer structure of the building that houses the reactor appeared to have blown off, which could suggest the containment building surrounding the reactor had already been breached. Earlier the operator released what it said was a tiny amount of radioactive steam to reduce the pressure and the danger was minimal because tens of thousands of people had already been evacuated from the vicinity.

              Japan's Nuclear and Industrial Safety Agency said two radioactive substances, cesium and radioactive iodine had been detected at one of the reactors at the Fukushima 1 plant reports NHK. The evacuation zone around the plants was extended from 3 kilometres to 10. Analysts say there is a low risk of a wide-scale nuclear disaster because the reactors are light-water units, meaning an explosion is unlikely. Radiation levels inside one of the reactors were recorded at 1,000 times their normal levels, and outside the plant at eight times their normal amount.

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              • #37

                Samedi 12 Mars 2011 -- Au lendemain du terrible tremblement de terre de magnitude de 8,9, suivi d'un tsunami dévastateur et de nombreuses répliques, le Japon compte ses victimes et le bilan ne cesse de s'aggraver. Plus de 1.400 personnes sont mortes ou portées disparues, 215.000 ont été déplacées et sont actuellement dans des abris, tandis que des millions d'autres sont sans électricité. De très fortes inquiétudes pèsent sur les installations nucléaires du pays et notamment sur la centrale nucléaire de Fukushima (à 250 km au nord de Tokyo), autour de laquelle 45.000 personnes ont été évacuées. Une explosion s'y est produite et les murs et le toit d'un réacteur se sont effondrés... Une fusion serait à craindre dans le réacteur, selon l'Agence de sécurité nucléaire et industrielle, ce qui peut laisser craindre un grave accident nucléaire. Un total de onze réacteurs sur 55 se sont automatiquement arrêtés après le séisme. Dans la région de Sendaï, dévastée par le tsunami, les secours sont à pied d'oeuvre. Coupée du reste du pays, seule l'armée nippone peut s'y rendre pour venir en aide aux populations sinistrées. Ce sont 50.000 sauveteurs qui ont été envoyés sur place.

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                • #38

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                  • #39

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                    • #40

                      Tokyo, March 12, 2011 -- Japan's government late Saturday extended the evacuation radius around the quake-damaged Fukushima I and II power plants to 20 kilometres, a news report said. The provincial government had received those orders from the cabinet of Prime Minister Naoto Kan, the Jiji Press news agency reported. Radiation levels near the plants have fallen after a spike following an explosion at the Fukushima I plant earlier Saturday, which apparently led to the collapse of the roof of a building, Kyodo News reported, quoting Japan's nuclear safety agency. The evacuation radius previously was 10 kilometres for the Fukushima I plant and 3 kilometres for Fukushima II. The plants are located about 150 kilometres north of Tokyo.

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                      • #41

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                        • #42

                          Samedi 12 Mars 2011 -- Selon l'astrophysicien algérien Loth Bonatiro, demain dimanche on saura si l’Algérie est menacée ou non par un fort séisme après la surveillance de l’activité du soleil qui a un impact direct sur le tsunami qui a frappé hier pour la première fois le Japon depuis 140 ans. Bonatiro, dans un entretien au téléphone, a déclaré à Ennahar, que la confirmation de cette hypothèse sera connue dans deux ou trois jours à compter de vendredi, après avoir surveillé l’activité du soleil et son impact sur l’activité terrestre comme ça a été le cas de l’explosion du volcan dans la région de Hawaï le quatre mars derniers. La magnitude du séisme du Japon qui a atteint 8.8 est fortement liée à l’activité du soleil. Le tsunami a eu lieu dans une région fragile entre le Japon et l’Indonésie. Selon Bonatiro, même si un tsunami frappe la région de l’Afrique du nord, il sera de faible intensité.

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                          • #43

                            Samedi 12 Mars 2011 -- Le Japon doit-il craindre pour ses centrales nucléaires après le séisme qui l’a touché vendredi 11 mars? Une explosion a eu lieu samedi 12 mars dans la matinée (15H30 heure locale) près du réacteur numéro un de la centrale de Fukushima Daiichi. Le toit et les murs du bâtiment qui abritent le réacteur se sont effondrés. Quatre personnes ont été hospitalisées. L'agence de sûreté nuclaire japonaise a annoncé que le caisson du réacteur n'aurait pas subi de dégâts. Des émissions radioactives ont été enregistrées dans la matinée. Claude Lacoste président de l’autorité de sûreté nucléaire, a fait un point sur la situation ce samedi à 13H: «La situation est à l’évidence grave. Malheureusement les informations dont nous disposons sont incomplètes, ce qui tient au fait que nos interlocuteurs sont concentrés sur la gestion de al crise. Le Japon compte 55 réacteurs, dont 11 sur la côte Pacifique qui se sont donc retrouvés face au Tsunami. Ils ont été immédiatement mis à l'arrêt mais très vite des problèmes se sont concentrés sur une centrale, Fukushima Daiichi, qui a connu des problèmes de refroidissement et d’alimentation électrique sur le réacteur numéro 1. Puis il s’est produit une explosion sur le bâtiment de ce réacteur. On peut toutefois noter un point positif : la direction des vents qui soufflent vers le Pacifique. Il est trop tôt pour tirer de retour d’expérience de cet accident." Sur la question de la portée de cet accident, Claude Lacoste a assuré qu' "il y aura des mesures de la qualité radiologique de l’air en France pour voir si on enregistre des retombées sur notre territoire.» Des données seront affichées en temps réel sur le site de l’ISRN (Institut de radioprotection et de sûreté nucléaire). Avec 55 réacteurs et deux autres en construction, le Japon est un des pays les plus nucléarisés au monde, derrière les Etats-Unis (104 réacteurs) et la France (59 réacteurs).

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                            • #44

                              TOKYO, March 12, 2011 (Reuters) -- The wind at a nuclear plant in Japan that is leaking radiation is blowing from the south, which could affect residents north of the facility, Japan's national weather forecaster said on Saturday. The Fukushima Daiichi plant, operated by Tokyo Electric Power Co's , is located about 240 kilometres north of Tokyo on the country's north eastern coastline. The weather agency said the wind direction may shift later so that it blows from the north west towards the sea. The direction of the wind is a key factor in judging possible damage on the environment from the radiation leaking from the plant, which was hit by Japan's biggest earthquake on record and a tsunami. The Japan Meteorological Agency said the weather on Sunday is likely to be clear, with wind coming from the west and later from the south. The plant was damaged by Friday's 8.9 magnitude quake, which sent a 10-metre (33-foot) tsunami ripping through towns and cities across the northeast coast. Japanese media estimate that at least 1,300 people were killed.

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                              • #45

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