Flashback 2 11 March 2011 Reactor gases vented, first evacuations

To update the Guardian article below, I have just heard that the reactor has been forced to vent radioactive gas to the
biosphere. This was done to relief pressure on the containment building. 7.44am Adelaide time.


Japan earthquake forces thousands to evacuate in nuclear plant emergency

Experts warn that order to flee homes signals a serious problem at Fukushima power station in tsunami zone
# Terry Macalister, Fiona Harvey, John Vidal and Justin McCurry
# guardian.co.uk, Friday 11 March 2011 20.35 GMT

Japan earthquake forces thousands to evacuate in nuclear plant emergency

Experts warn that order to flee homes signals a serious problem at Fukushima power station in tsunami zone
* Terry Macalister, Fiona Harvey, John Vidal and Justin McCurry
* guardian.co.uk, Friday 11 March 2011 20.35 GMT
* Article history

Fukushima nuclear power plant Fukushima’s coastal position in the Japanese north-east left it exposed to the full force of the tsunami Photograph: The Tokyo Electric Power/EPA

Thousands of people were being evacuated from their homes as Japan scrambled to shut down reactors and prevent a catastrophic meltdown at a nuclear plant that bore the brunt of the earthquake and subsequent tsunami, amid reports that its cooling system had failed.

[The US air force flew in coolant to help prevent nuclear fuel rods from overheating at the Fukushima plant, which from its coastal position in the Japanese north-east was starkly exposed to the full force of the tsunami.] Incorrect. Reuters reports US in fact supplied generators needed to get the cooling system going.

The Japanese government declared a nuclear emergency, and the trade minister admitted that a radiation leak was a distinct possibility as concerns mounted that the cooling system had failed, with grave implications for the integrity of the hundreds of tonnes of radioactive fuel at the site. The sight of 2,800 local residents forced to flee their homes evoked scenes witnessed after the massive Chernobyl accident in Ukraine, almost exactly 25 years ago.

Japanese authorities said pressure was rising inside the plant with the risk of a radiation leak, according to the Jiji news agency. One British atomic engineer said the evacuation suggested a radioactive leak remained a possibility.

“It looks very serious. Obviously we do not know exactly what is going on but evacuating people is normally only a matter of last resort when there is only one containment layer left to be breached,” said John Large, a member of the British Nuclear Engineering Society and a fellow of the Royal Society.

If radioactivity has broken through into the final dome over the top of the plant this would put the incident on a par with the Three Mile Island accident in the US which cost $1bn in 1979 money.

Another nuclear expert said that if the water cooling system had broken down, the consequences could be dire.

“One critical safety issue is the maintenance of water cooling systems to ensure that the nuclear fuel inside the reactor core does not heat up to unsafe levels,” said Shaun Burnie, a consultant on the nuclear industry.

He said the reactor’s operator, Tokyo Electric, had apparently been unable to pump cooling water into the 40-year-old reactors for at least three hours.

“The possibility is that the reactor fuel is already damaged. If they are unable to restore coolant pump capacity then the fuel will continue to heat up, eventually the fuel will be exposed to air at which point a whole series of events can unfold, including steam explosions, fuel meltdown and worse case is loss of containment. The last thing the people of Japan need after the tragedy of this earthquake and tsunami is a nuclear catastrophe.”

Others cautioned that it was too soon to declare that a nuclear disaster was imminent. Sue Ion, fellow of the Royal Academy of Engineering, said the evacuations could equally be a sensible precaution and noted that Japanese reactors were built to withstand the rigours of nature in an earthquake-prone part of the world. “As this is an earthquake zone, the Japanese apply very rigorous standards, with robust designs and regulations,” she said.

Paul Haigh, a fellow of the Institution of Chemical Engineers, added: “All Japanese reactors are designed to withstand substantial earthquakes. Instrumentation is provided for the early detection of tremors which would lead to a controlled shutdown of the reactor. These systems appear to have successfully shut down the affected reactors. Modern western reactors, including those planned for the UK, are already designed to withstand significant seismic events.”

Rather than undermining public faith in nuclear energy, this incident would highlight its safety, Ion predicted. “People should gain confidence from the fact that these plants have shut down as they should be.”

The nuclear industry is currently in the middle of a surprise renaissance with dozens of new plants planned in Britain, America and China amid deeper public worries about energy shortages and low carbon ways of tackling climate change.

The sector had hoped fears about safety had receded in the public mind and was steeling itself for a wave of bad publicity surrounding the 25th anniversary of Chernobyl, where work is still under way to dismantle the plant and make safe spilled radioactive fuel. This plant – built and operated under the Soviet system – blew up during a safety test although the accident was blamed on a mixture of bad design and human error.

Failure of the cooling system – and the diesel back-up generator – at the Fukushima 1 plant in Onahama raises questions about what has gone wrong so far and what could happen in future. Another British nuclear engineer who asked not to be named said: “It is difficult to know exactly what has happened here but any shutdown is expensive and any systems failures of wider concern. The water cooling systems around the reactors are driven primarily by the nuclear power but if that is not working then via diesel generator.”

Large said any complete power outage would quickly lead to the reactor overheating and the potential meltdown of the fuel under temperatures that could reach 1,200C. Different mechanical and chemical reactions could potentially lead to a hydrogen explosion, he added.

All of this could be “astronomically” expensive given the heavily populated and insured population of Japan, said Large who has also visited Fukushima. The engineer said he was concerned that the nuclear industry and local political system had a reputation for considerable secrecy that would not make it easy to discern what had gone wrong.

Earthquakes often close Japanese nuclear plants, some of which are built close to known faultlines. In 1999, 2004, 2005, 2007 and 2009 reactors shut down because of seismic activity.

Confidence in Japan’s nuclear safety was dented by a series of scandals in the late 1990s when the Tokyo Electric Power Company, owner of the Kashiwazaki-Kariwa plant, admitted falsifying safety data and concealing cracks in the core structures of its reactors. The same plant was seriously damaged by a major earthquake in 2007, but the owners tried to conceal a radiation leak. Much of the plant had to be closed for 21 months at a cost of more than $3bn.

end quote

Obviously, given the history of disaster and suppressed truth regarding nuclear technology since 1945 and ongoing, Australia should not build nuclear reactors. Rather proven solar-thermal power plants located in the vast areas of Australia which are suitable for these plants.

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