Still critical: radiation levels at Fukushima can kill in minutes

Latest readings from tsunami-stricken nuclear plant overturn claims that reactors have been made safe

Tokyo

A lethal level of radiation has been detected inside one of the reactors at the Fukushima nuclear power plant, throwing fresh doubts over the operator's claims that the disabled complex is under control.

Engineers for Tokyo Electric Power Co (Tepco) say readings of airborne radiation inside the containment vessel of Reactor 2 showed nearly 73 sieverts per hour this week, the highest since the crisis began following the earthquake and tsunami on 11 March last year. Exposure to radiation at that level is deadly within minutes, according to Japan's public broadcaster, NHK.

Tepco said the find would have "no impact" on the company's long-term plans to decommission the plant's six reactors. "We were not surprised that the radiation was this high because the reading was taken from inside the pressure vessel,"a spokesperson said.

Tepco announced in December that the Daiichi complex had achieved a state of cold shutdown, meaning that radiation emissions are under control and the temperature of its 260 tons of nuclear fuel has stabilised below boiling point. The company plans to remove the fuel and dismantle the plant's steel and concrete structure – a task it estimates will take decades.

But engineers have only a rough idea of where the melted fuel inside three of the six reactors is, or how badly it has corroded the base of the reactors and their containment vessels. Reactors 1 and 3 are too badly damaged to allow close inspection, while engineers had to use modified equipment to peer inside Reactor 2 this week for only the second time since the earthquake.

Workers are able to work near Reactor 2 only for short periods and Tepco says it will need to develop devices to withstand the harsh conditions inside.

In addition, an industrial endoscope inserted into the reactor's containment vessel on Monday found only 60cm of water inside, far below the three to six metres expected. Tepco – which has poured thousands of gallons of water on to the crippled reactors in an effort to keep the fuel cool – insists that, despite the low level, the melted fuel is underwater "judging by the temperature of 48.5C to 50C".

Critics say the fresh findings illustrate the still precarious state of the complex. "The problem for Tepco is that the damage is so severe to the base of the reactor, and the amount of water is so low, that any interruption to the water pumping could be serious," said Shaun Burnie, an independent nuclear consultant. Mr Burnie said the company must get more water on to the melted fuel and stop contamination from making its way into the environment.

The difficulties of that process were illustrated again this week when the plant's makeshift cooling system sprang another leak. Workers estimate that about 80 litres of contaminated water escaped from pipes carrying water to and from the Pacific. The build-up of toxic water is another major headache for Tepco, as the company is running out of space to store it.

The struggle to decommission the Daiichi plant continues as a potentially epic battle looms between pro- and anti-nuclear forces. Only one of Japan's 54 reactors is still online after Reactor 6 of the world's largest nuclear complex, Kashiwazaki-Kariwa, shut down for maintenance earlier this week.

With Japan's nuclear power capacity down to less than two per cent, from 30 per cent, the Government and businesses fear a summer power crisis unless idling plants are restarted. However, each plant needs approval from sceptical local communities, and post-Fukushima surveys put opposition to nuclear power in Japan at around 80 per cent. Public fears have forced regulators to order tests to determine whether the plants will stand up to another large earthquake or tsunami.

Tepco's disgraced executives also face a 5.5-trillion-yen (£42bn) lawsuit by shareholders. "The company repeatedly ignored tsunami and earthquake research showing that the plant would be overwhelmed," said lead lawyer Hiroyuki Kawai this week. "The plant was run haphazardly and carelessly."

The disaster: How it unfolded

Cooling systems down

The 9.0-magnitude earthquake and a tsunami more than 15 metres tall knocked out cooling systems at the six-reactor plant. Meltdowns are believed to have occurred at reactors 1, 2 and 3.

Explosions and radiation leaks

Hydrogen explosions occurred at the No 1 and No 3 reactor buildings a few days after the quake. Radiation leaks forced some 80,000 residents to evacuate the immediate area and more fled voluntarily.

Spent-fuel pool catches fire

Reactor No 4 was under maintenance and 550 fuel rods had been transferred to its spent-fuel pool, which already contained about 1,000 fuel rods. The pool caught fire and caused an explosion.

Cold shutdown

Reactors 5 and 6 reached cold shutdown (meaning water used to cool the fuel rods fell below boiling point) 10 days after the tsunami – but it took more than nine months to achieve that at reactors 1, 2 and 3.

Reuters

Sport
footballLIVE City face Stoke, while Warnock returns to Palace dugout
Arts and Entertainment
books
Life and Style
3D printed bump keys can access almost any lock
gadgets + techSoftware needs photo of lock and not much more
News
i100
PROMOTED VIDEO
Have you tried new the Independent Digital Edition apps?
News
ebooksAn evocation of the conflict through the eyes of those who lived through it
Arts and Entertainment
Inside the gallery at Frederick Bremer School in Walthamstow
tvSimon Usborne goes behind the scenes to watch the latest series
Life and Style
Silvia says of her famous creation: 'I never stopped wearing it. Because I like to wear things when they are off the radar'
fashionThe fashion house celebrated fifteen years of the punchy pouch with a weighty tome
Arts and Entertainment
Gregg Wallace in Summer's Supermarket Secrets
tv All of this year's 15 contestants have now been named
News
i100Steve Carell selling chicken, Tina Fey selling saving accounts and Steve Colbert selling, um...
Life and Style
A picture taken on January 12, 2011 shows sex shops at the Paris district of Pigalle.
newsThe industry's trade body issued the moratorium on Friday
Arts and Entertainment
Could we see Iain back in the Bake Off tent next week?
tv Contestant teased Newsnight viewers on potential reappearance
News
i100
News
The slice of Prince Charles and Princess Diana's wedding cake and the original box from 29 July 1981
newsPiece of Charles and Diana's wedding cake sold at auction in US
Voices
The Ukip leader has consistently refused to be drawn on where he would mount an attempt to secure a parliamentary seat
voicesNigel Farage: Those who predicted we would lose momentum heading into the 2015 election are going to have to think again
Arts and Entertainment
Cara Delevingne made her acting debut in Anna Karenina in 2012
film Cara Delevingne 'in talks' to star in Zoolander sequel
Sport
Mario Balotelli pictured in his Liverpool shirt for the first time
football
Independent
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
santorini
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Junior VB.NET Application Developer (ASP.NET, SQL, Graduate)

£28000 - £30000 per annum + Benefits + Bonus: Harrington Starr: Junior VB.NET ...

C# .NET Web Developer (ASP.NET, JavaScript, jQuery, XML, XLST)

£40000 - £50000 per annum + Benefits + Bonus: Harrington Starr: C# .NET Web De...

Clinical Negligence Solicitor

Highly Competitive Salary: Austen Lloyd: HAMPSHIRE MARKET TOWN - A highly attr...

Network Engineer (CCNP, CCNA, Linux, OSPF, BGP, Multicast, WAN)

£35000 per annum: Harrington Starr: Network Engineer (CCNP, CCNA, Linux, OSPF,...

Day In a Page

Ukraine crisis: The phoney war is over as Russian troops and armour pour across the border

The phoney war is over

Russian troops and armour pour into Ukraine
Potatoes could be off the menu as crop pests threaten UK

Potatoes could be off the menu as crop pests threaten UK

The world’s entire food system is under attack - and Britain is most at risk, according to a new study
Gangnam smile: why the Chinese are flocking to South Korea to buy a new face

Gangnam smile: why the Chinese are flocking to South Korea to buy a new face

Seoul's plastic surgery industry is booming thanks to the popularity of the K-Pop look
From Mozart to Orson Welles: Creative geniuses who peaked too soon

Creative geniuses who peaked too soon

After the death of Sandy Wilson, 90, who wrote his only hit musical in his twenties, John Walsh wonders what it's like to peak too soon and go on to live a life more ordinary
Caught in the crossfire of a cyber Cold War

Caught in the crossfire of a cyber Cold War

Fears are mounting that Vladimir Putin has instructed hackers to target banks like JP Morgan
Salomé's feminine wiles have inspired writers, painters and musicians for 2,000 years

Salomé: A head for seduction

Salomé's feminine wiles have inspired writers, painters and musicians for 2,000 years. Now audiences can meet the Biblical femme fatale in two new stage and screen projects
From Bram Stoker to Stanley Kubrick, the British Library's latest exhibition celebrates all things Gothic

British Library celebrates all things Gothic

Forthcoming exhibition Terror and Wonder: The Gothic Imagination will be the UK's largest ever celebration of Gothic literature
The Hard Rock Café's owners are embroiled in a bitter legal dispute - but is the restaurant chain worth fighting for?

Is the Hard Rock Café worth fighting for?

The restaurant chain's owners are currently embroiled in a bitter legal dispute
Caribbean cuisine is becoming increasingly popular in the UK ... and there's more to it than jerk chicken at carnival

In search of Caribbean soul food

Caribbean cuisine is becoming increasingly popular in the UK ... and there's more to it than jerk chicken at carnival
11 best face powders

11 best face powders

Sweep away shiny skin with our pick of the best pressed and loose powder bases
England vs Norway: Roy Hodgson's hands tied by exploding top flight

Roy Hodgson's hands tied by exploding top flight

Lack of Englishmen at leading Premier League clubs leaves manager hamstrung
Angel Di Maria and Cristiano Ronaldo: A tale of two Manchester United No 7s

Di Maria and Ronaldo: A tale of two Manchester United No 7s

They both inherited the iconic shirt at Old Trafford, but the £59.7m new boy is joining a club in a very different state
Israel-Gaza conflict: No victory for Israel despite weeks of death and devastation

Robert Fisk: No victory for Israel despite weeks of devastation

Palestinians have won: they are still in Gaza, and Hamas is still there
Mary Beard writes character reference for Twitter troll who called her a 'slut'

Unlikely friends: Mary Beard and the troll who called her a ‘filthy old slut’

The Cambridge University classicist even wrote the student a character reference
America’s new apartheid: Prosperous white districts are choosing to break away from black cities and go it alone

America’s new apartheid

Prosperous white districts are choosing to break away from black cities and go it alone