
Plans are being drawn up to evacuate every British national in Japan amid mounting fears of a nuclear catastrophe. Thousands of Britons were last night warned to leave Tokyo and all other areas under threat of radiation poisoning.

The Foreign Office is even chartering additional planes to ensure that all British citizens can leave the country on free-of-charge rescue flights - as thousands of terrified passengers cram into Tokyo airport attempting to flee.



It comes as the Japanese authorities resorted to dumping water on over-heating reactors at the Fukushima nuclear plant from helicopters in a desperate last-ditch attempt to stop a catastrophic meltdown.

Experts have warned that they have 48 hours to avoid another Chernobyl.



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Dangerous mission: the helicopters dropped four loads on the reactor as pilots were restricted to 40 minutes flying time over the Fukushima plant

Desperate: A military helicopter dumps water onto the number three reactor at the stricken Fukushima nuclear plant today

Leaving: Worried residents wait to enter the Immigration Bureau of Japan in Tokyo as they evacuate the city in the wake of the earthquake and fears of a nuclear catastrophe. Foreigners need re-entry permits in advance if they plan to revisit the country

Collecting water: The Self-Defense Forces's helicopter scoops seawater on Japan's northeast coast en route to the Fukushima plant

Get out: A growing number of countries are joining the UK in organising flights to evacuate their citizens from Japan

Even when removed from reactors, uranium rods are still extremely hot and must be cooled for months, possibly longer, to prevent them from heating up again and emitting radioactivity.

That means that nuclear fuel rods at both the reactors could overheat further and release more radiation.

American officials have also said that they believe the fuel holding pools at reactor three and four have boiled dry causing 'extremely high' radiation levels.

The dumping was intended both to help cool the reactor and to replenish water in a pool holding spent fuel rods. The plant's owner, Tokyo Electric Power Co., said earlier that the pool was nearly empty, which might cause the rods to overheat.

The aircraft dumped at least four loads of at least 2,000 gallons each, on the reactor, though much of the water appeared to be dispersed in the air.

Two CH-47 Chinook helicopters began dumping seawater on the damaged reactor of Unit 3 at the Fukushima complex at 9.48am local time this morning as Defence Minister Toshifumi Kitazawa told reporters that emergency workers had no choice but to try the water dumps before it was too late.

It heightened suspicions that the crisis at the plant – already ranked the second-worst nuclear disaster after Chernobyl – is worse than the Japanese authorities have publicly let on.

The advice to flee – echoed by other countries around the world – followed a meeting of the Cabinet’s emergency Cobra committee to discuss the meltdown-threatened Fukushima nuclear plant.

The plights of Britons will be assessed on a case-by-case basis according to the personal trauma they have suffered. Those deemed to have been directly affected could include those who were in the area of the disaster as well as those whose relatives have died or have lost all their possessions.

There will be no charge for British nationals and their immediate families who were 'directly affected' by the tsunami. However those who were not badly caught up will have to pay £600 per person for the chartered flights.

However it has chartered several planes for free-of-charge rescue flights which will fly to Hong Kong, from where victims can make arrangements to make it back to the UK.

The Foreign Office says Britons should still try to get commercial flights out of Japan if possible.

WHAT SHOULD BRITONS STRANDED IN JAPAN DO TO GET OUT?

Last ditch: A Japanese military helicopter can be seen in the top left of the picture as it dumps water onto reactors 3 and 4 at Fukushima nuclear plant Emergency workers are struggling to keep a constant supply of water pumping into the holding pools and officials last night admitted that much of the monitoring equipment in the plant was broken and it was impossible to monitor the situation.

'We haven't been able to get any of the latest data at any spent fuel pools. We don't have latest water levels, temperatures, none of the latest information,' an official said. There are also frantic efforts to restore power to the coolant pumping system that was knocked out by the tsunami on Friday. Chief Cabinet Secretary Yukio Edano said that along with the helicopter water drops, special police units would use water cannons - normally used to quell rioters - to spray water onto the Unit 4 storage pool. The high-pressure water cannons will allow emergency workers to stay farther away. One French expert warned that the plant is just hours away from disaster. Thierry Charles of the Institute for Radiological Protection and Nuclear Safety told the Telegraph: 'The next 48 hours will be decisive. I am pessimistic because, since Sunday, I have seen that almost none of the solutions has worked.'



40 YEARS OF DOUBT ON NUCLEAR DESIGNS

By DANIEL BATES The design of the reactors at the stricken Fukushima power plant has been called into question for almost 40 years.

As far back as 1972, experts said the Mark 1 should be discontinued because its containment vessel was not as robust as alternatives.

One report said such reactors had a 90 per cent probability of bursting should the fuel rods overheat and melt in an accident.

A clutch of engineers also resigned their posts rather than carry on with a project they deemed to be unsafe.

In a nuclear reactor the containment vessel is considered the last line of defence to stop a meltdown.

It is usually a steel and cement ‘tomb’ and is designed to stop the melting fuel rods sending lethal radiation into the atmosphere.

The cheaper Mark 1s, however, are less robust, smaller, and have long been thought to be more likely to fail in an emergency.

They were designed in the U.S. in the 1960s by the utility giant General Electric.Five of the six reactors at the Fukushima plant are Mark 1s.

In 1972, the U.S. Atomic Energy Commission said the design should be discontinued because it was more susceptible to explosion and rupture from a build-up in hydrogen – which may have happened at Fukushima. In 1975 engineer Dale Bridenbaugh and two of his colleagues at General Electric quit work on a Mark 1 because they did not feel comfortable about safety.



About 17,000 British nationals are thought to be in the country, mostly in Tokyo. Last night’s Foreign Office warning stopped short of ordering them to leave the country – a diplomatic gesture which will be welcomed by the Japanese government.

But officials conceded that in reality most Britons will have few options but to leave Japan if they want to heed the advice.

Thousands of Japanese citizens are already fleeing Tokyo for the south.

Officials yesterday insisted there was no significant risk to human health in Tokyo, which is less than 140 miles south of Fukushima.



But Europe’s energy chief Guenther Oettinger warned the huge plant was ‘effectively out of control’ – sparking fears of a meltdown, which could send a radioactive cloud into the atmosphere.

He warned of ‘further catastrophic events, which could pose a threat to the lives of people on the island’. Mr Oettinger predicted the dire situation could take a further turn for the worse ‘within hours’.

The Japanese public was also unconvinced by its government’s reassurances. The mayor of Minimisoma, which is 12 miles from the Fukushima plant, said: ‘We weren’t told when the first reactor exploded, we only heard about it on television. The government doesn’t tell us anything. We are isolated. They’re leaving us to die.’

The Foreign Office insisted there was ‘no real human health issue’ outside the 20-mile exclusion zone surrounding the plant.

But it warned that panic caused by the crisis meant there were ‘potential disruptions to the supply of goods, transport, communications, power and other infrastructure’ in Tokyo.

Officials confirmed that contingency plans were being drawn up for an airlift of British nationals if the crisis worsens.



The United States is also evacuating the family members of officials stationed in Japan.

The warning came as the Japanese maid the increasingly desperate attempts to contain the crisis at the Fukushima plant.

A core team of 180 emergency workers has been at the forefront of the struggle at the plant, rotating in and out of the complex to try to reduce their radiation exposure.

But experts said that anyone working close to the reactors was almost certainly being exposed to radiation levels that could, at least, give them much higher cancer risks.

'I don't know any other way to say it, but this is like suicide fighters in a war,' said Keiichi Nakagawa, associate professor of the Department of Radiology at University of Tokyo Hospital.

Escape: residents gather up their belongings and form a queue as they wait to board a bus out of Sendai, north eastern Japan, yesterday

Destroyed: Damage after the earthquake and tsunami at Fukushima Daiichi nuclear plant, 240 km (150 miles) north of Tokyo, is seen in this satellite image