Japan pictures likely show melted Fukushima fuel for first time — Bloomberg

” New images show what is likely to be melted nuclear fuel hanging from inside one of Japan’s wrecked Fukushima reactors, a potential milestone in the cleanup of one of the worst atomic disasters in history.

Tokyo Electric Power Co. Holdings Inc., Japan’s biggest utility, released images on Friday showing a hardened black, grey and orange substance that dripped from the bottom of the No. 3 reactor pressure vessel at Fukushima, which is likely to contain melted fuel, according to Takahiro Kimoto, an official at the company. The company sent a Toshiba-designed robot, which can swim and resembles a submarine, to explore the inside of the reactor for the first time on July 19.

“Never before have we taken such clear pictures of what could be melted fuel,” Kimoto said at a press briefing that began at 9 p.m. Friday in Tokyo, noting that it would take time to analyze and confirm whether it is actually fuel. “We believe that the fuel melted and mixed with the metal directly underneath it. And it is highly likely that we have filmed that on Friday.”

If confirmed, the substance — which has the appearance of icicles — would be the first discovery of the fuel that melted during the triple reactor accident at Fukushima six years ago. For Tokyo Electric, which bears most of the clean-up costs, the discovery would help the utility design a way to remove the highly-radioactive material.

The robot, which is about 30 centimeters (12 inches) long, will search for melted fuel at the bottom of the reactor on Saturday. It is possible that the company will take more pictures of what could be melted fuel spread across the floor and lower levels, according to Tokyo Electric’s Kimoto. Fuel from a nuclear meltdown is known as corium, which is a mixture of the atomic fuel rods and other structural materials.

Early Signs

“It is important to know the exact locations and the physical, chemical, radiological forms of the corium to develop the necessary engineering defueling plans for the safe removal of the radioactive materials,” said Lake Barrett, a former official at the U.S. Nuclear Regulatory Commission who was involved with the cleanup at the Three Mile Island nuclear power plant in the U.S. “The recent investigation results are significant early signs of progress on the long road ahead.”

Because of the high radioactivity levels inside the reactor, only specially designed robots can probe the unit. And the unprecedented nature of the Fukushima disaster means that Tepco, as the utility is known, is pinning its efforts on technology not yet invented to get the melted fuel out of the reactors.

Removal Plans

The company aims to decide on the procedure to remove the melted fuel from each unit as soon as this summer. And it will confirm the procedure for the first reactor during the fiscal year ending March 2019, with fuel removal slated to begin in 2021.

Decommissioning the reactors will cost 8 trillion yen ($72 billion), according to an estimate in December from the Ministry of Economy, Trade and Industry. Removing the fuel is one of the most important steps in a cleanup that may take as long as 40 years.

Similar to the latest findings on Friday, Tepco took photographs in January of what appeared to be black residue covering a grate under the Fukushima Dai-Ichi No. 2 reactor, which was speculated to have been melted fuel. However, a follow-up survey by another Toshiba-designed robot in February failed to confirm the location of any melted fuel in the reactor after it got stuck in debris.

A robot designed by Hitachi-GE Nuclear Energy Ltd. also failed to find any melted fuel during its probe of the No. 1 reactor in March.

The significance of Friday’s finding “might be evidence that the robots used by Tepco can now deal with the higher radiation levels, at least for periods of time that allow them to search parts of the reactor that are more likely to contain fuel debris,” M.V. Ramana, professor at the Liu Institute for Global Issues at the University of British Columbia, said by email.

“If some of these fragments can be brought out of the reactor and studied, it would allow nuclear engineers and scientists to better model what happened during the accident.” ”

by Stephen Stapczynski, Bloomberg

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Japanese robot probes the radioactive water at Fukushima’s nuclear reactor to find melted fuel — Daily Mail

” A Japanese robot has begun probing the radioactive water at Fukushima’s nuclear reactor.

The marine robot, nicknamed the ‘little sunfish’, is on a mission to study structural damage and find fuel inside the three reactors of the devastated plant.

Experts said remote-controlled bots are key to finding fuel at the dangerous site, which has likely melted and been submerged by highly radioactive water.

The probe – about the size of a loaf of bread – is equipped with lights, manoeuvres using tail propellers and collects data using two cameras and a dosimeter radiation detector.

Plant operators chose to send the robot inside the containment vessel of the No. 3 reactor because it has highest known water levels out of the the three reactors.

The robot entered the structure at 6.30am JST (10.30 BST, 5.30 ET) through a pipe connected to the containment vessel.

The marine machine, which was attached to cables, then swam to the area just below the reactor pressure vessel inside to take images.

New images taken by the robot show how parts of the system, including the control rod, have been damaged by radiation.

On Friday, the robot will continue its travels to the bottom of the containment vessels, where melted fuel deposits are believed to have accumulated.

In 2011, a 10-metre-high tsunami that killed nearly 19,000 people crashed into Japan’s Fukushima nuclear power plant, leading to several meltdowns.

Five years after the disaster, researchers are still struggling to clean up the highly dangerous radioactive materials in water of the wasting reactors.

It’s estimated that plant officials have only located 10 per cent of the waste fuel left behind after the nuclear meltdowns.

And the damaged plant is believed to be leaking small amounts of the radioactive waste into the Pacific Ocean, which could be travelling as far as the west cost of the US.

Researchers are now pinning their hopes on the remote-controlled sunfish robot to locate the lost fuel in order to work out the safest way to remove it.

During a demonstration of the device at a test facility near Tokyo last month, the probe slowly slid down from a rail and moved across the water.

A team operated it remotely, with one guiding the robot while another adjusted a cable that transmits data and serves as its lifeline.

Japan hopes to locate and start removing fuel from the reactors after Tokyo’s 2020 Olympics.

In earlier operations, snake and scorpion-shaped robots became stuck inside two reactors.

The scorpion robot’s crawling function failed and it was left inside the plant’s Unit 2 containment vessel.

The other, designed for cleaning debris for the ‘scorpion’ probe, was called back after two hours when two of its cameras stopped working after its total radiation exposure reached 1,000 Sievert – a level that would kill a human within seconds.

The plan had been to use the robot for 10 hours at an exposure level of 100 Sievert per hour.

The swimming robot shown was co-developed by electronics and energy giant Toshiba and the government’s International Research Institute for Nuclear Decommissioning. “

by Daisy Dunne, Mail Online and Associated Press

source with photos and video

Britain and Japan sign nuclear energy cooperation agreement — The Telegraph

” Britain and Japan have signed an agreement that significantly expands cooperation in the nuclear energy sector and paves the way for Japanese companies to construct nuclear plants in the UK.

It also covers cooperation in the areas of decommissioning and decontamination and it is anticipated that the deal will give British companies with advanced technologies greater access to projects at the Fukushima Daiichi nuclear plant, where three of the six reactors suffered melt-downs after the March 2011 earthquake and tsunami disaster.

The memorandum of understanding was signed in Tokyo on Thursday by Hiroshige Seko, the Japanese trade and industry minister, and Greg Clark, the business and energy secretary.

The agreement is the first of its kind for Japan, while Mr Clark described it as “vital” to the UK’s industrial strategy and the development of clean energy sources.

One of the key components of the agreement is the proposals by Hitachi and Toshiba to build new reactors in Britain.

Horizon Nuclear Power, bought by Hitachi from a German company in 2012, has delivered the outline of a project at Wylfa Newydd in Wales, and has plans to build as many as six reactors in the UK. Toshiba joint venture NuGeneration is planning a nuclear plant in Cumbria and is considering additional projects.

Speaking in Tokyo last week, Philip Hammond, the Chancellor, said: “The technology is proven and well-known. Hitachi and Toshiba have the technology. The challenge really is financing, not a technical or commercial challenge.”

The two governments are to review investment and lending for Horizon through the Japan Bank for International Cooperation and the Development Bank of Japan. Financing of the project from the Japanese side is expected to reach Y1 trillion (£7 billion).

Japan is particularly keen for the projects to go ahead after its previous attempt to export nuclear energy technology, to Vietnam, fell through.

Japan and Britain will also collaborate on nuclear research and development, as well as security.

The deal on nuclear energy with Japan has progressed smoothly, in contrast to the problems the £18 billion Hinkley Point C project encountered earlier in the year.

That scheme is a joint venture between EDF, which is 85 per cent owned by the French state, and China General Nuclear Power Corp. It was put on hold in July, over concerns about China’s involvement, before subsequently being given the go-ahead.

by Julian Ryall

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Japan’s nuclear export ambitions hit wall as Vietnam set to rip up reactor order — Japan Today

” TOKYO/HANOI — Vietnam is poised to abandon plans for Japanese firms to build a multi-billion dollar nuclear power plant, damaging Prime Minister Shinzo Abe’s drive to begin exporting reactors after the Fukushima disaster left the industry in deep-freeze at home. … ”

by Aaron Sheldrick and Ho Binh Minh

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Fukushima reactor makers not liable: Japan court — Channel NewsAsia

” TOKYO: A Japanese court on Wednesday (Jul 13) turned down a class action lawsuit seeking damages from nuclear plant makers Toshiba, Hitachi and GE over the Fukushima meltdown disaster, the plaintiffs, one of the companies and a report said.

About 3,800 claimants in the suit, hailing from Japan and 32 other countries including the United States, Germany and South Korea, had sought largely symbolic compensation from the nuclear power plant manufacturers.

Under Japanese liability law, nuclear plant providers are usually exempt from damage claims in the event of an accident, leaving operators to face legal action.

The plaintiffs’ lawyers, however, had argued that that violated constitutional protections on the pursuit of happy, wholesome and cultured livelihoods.

But the Tokyo District Court ruled that the law “is not unconstitutional”, according to lawyers for the plaintiffs.

“We knew it was difficult to win under the current legal system in Japan, but it’s clearly wrong that nuclear (plant) manufacturers don’t have to bear any responsibility for an accident,” Masao Imaizumi, 73, one of plaintiffs, told AFP.

“If they are spared responsibility, it could lead to disregard for product quality,” he said, adding that the plaintiffs will appeal.

Toshiba welcomed the decision. “The company recognises the verdict as an appropriate ruling handed out by the court,” it said in a statement.

Hitachi and GE’s Japan office could not be reached for comment. Japan’s Jiji Press also reported that the suit was rejected.

The suit – which sought just ¥100 (96 US cents) per claimant – was the first to be brought against nuclear power-plant suppliers over the accident, Akihiro Shima, lead lawyer for the plaintiffs, said previously.

The suit was first filed in January 2014 with just over 1,000 claimants, but more joined which saw the number nearly quadruple.

The plaintiffs had alleged that the companies failed to make necessary safety updates to the Fukushima reactors, swamped on Mar 11, 2011 by a magnitude 9.0 earthquake-sparked tsunami that lead to the worst nuclear accident since Chernobyl in 1986.

Embattled plant operator Tokyo Electric Power is already facing massive lawsuits and compensation costs. ”

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New robots deployed at Fukushima — The Wall Street Journal

” A team of rival Japanese companies unveiled a new family of robots to help workers with the daunting task of decommissioning the three reactors that went into meltdown at the Fukushima nuclear plant in 2011.

Fukushima operator Tokyo Electric Power Co. hopes to use the robots to begin decontaminating the second and third floors of the reactor buildings sometime after April. The robots are the latest tools developed in Japan’s trial-and-error struggles to clean up the nuclear disaster– which even the most optimistic say will take about half a century.

One robot will blast high-pressure water to decontaminate surfaces, while another will spray pellets of dry ice on contaminated objects for retrieval. The third will spray abrasives and then scrape the contaminated surfaces to remove radiated particles.

The robots were developed in a rare collaboration between competitors Mitsubishi Heavy, Hitachi GE Nuclear Energy, and Toshiba. Workers will also need to install large elevators on site so the robots can reach the second and third floors of the contaminated reactor buildings, and smaller robots will need to be deployed in cramped spaces.

If the robots can remove radiated debris on those floors, workers may be able to enter the area above the nuclear fuel containment vessel, to better assess the situation and possibly access equipment.

Although decontamination has progressed in areas outside the reactor buildings, so that workers no longer need to wear full face masks at about 90% of the entire site, radiation levels inside are too high for workers to enter.

Tepco hopes to start removing debris inside one of the reactors around 2021, but acknowledges that all dates are uncertain. ”

source with photo