Footage points to difficulty in removing possible melted fuel at Fukushima plant — The Mainichi

” The footage released on Jan. 30 by Tokyo Electric Power Co. (TEPCO) showing what could be melted fuel inside the No. 2 reactor at the disaster-stricken Fukushima No. 1 Nuclear Power Plant has highlighted the difficulty of salvaging the object, which is apparently stuck to footholds and other equipment at the facility.

TEPCO took the footage as part of its in-house probe into the No. 2 reactor and found that black and brown sediments — possible melted fuel — are stuck inside the reactor’s containment vessel over an extensive area.

“If what was captured in the footage was melted fuel, that would provide a major step forward toward trying our hand at unprecedented decommissioning work,” said Yoshiyuki Ishizaki, head of TEPCO’s Fukushima Revitalization Headquarters, during a press conference in the city of Fukushima on Jan. 30. “The finding may provide a major clue to future work to retrieve the object,” he added.

At the time of the March 2011 meltdowns at the plant, there were 548 nuclear fuel rods totaling some 164 metric tons inside the No. 2 reactor, but they apparently melted down after the loss of power sources for the core cooling system, with part of the melted fuel penetrating through the pressure vessel before cooling down at the bottom of the containment vessel. The temperature of the reactor core topped 2,000 degrees Celsius at the time of the accident, melting metals including nuclear fuel inside the reactor.

The melted fuel has since come in contact with underground water flowing from the mountain side, generating radioactively contaminated water every day. In order to dismantle the reactor, it is necessary to take out the melted fuel, but high radiation levels inside the reactor had hampered work to locate the melted debris.

On Jan. 30, apart from the footage, TEPCO also released 11 pictures taken inside the No. 2 reactor. The images show the sediments in question stuck to metal grate footholds and water is dripping from the ceiling. Further analysis of those images may provide information on the current status of the disaster and positional clues to decommissioning work.

The in-house probe, however, has only focused on the No. 2 reactor, and there is no prospect of similar probes into the No. 1 and No. 3 reactors starting anytime soon as they were severely damaged by hydrogen explosions following the 2011 meltdowns.

In April 2015, TEPCO introduced a remote-controlled robot into the No. 1 reactor by way of a through hole in its containment vessel, but the device failed to locate melted fuel inside due to high radiation levels. While the utility is planning to send a different type of robot into the No. 1 reactor this coming spring, it would be difficult to carry out a survey similar to that conducted at the No. 2 reactor, as radiation levels are high around the through hole in the No. 1 reactor’s containment vessel, from which a device could access to right below the No. 1 reactor.

The No. 3 reactor, meanwhile, holds roughly 6.5-meter-deep contaminated water inside its containment vessel, a far larger volume than that accumulated at the No. 1 and No. 2 reactors. TEPCO has thus been developing a robot that can wade through water. ”

by The Mainichi

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Nuclear fuel debris that penetrated reactor pressure vessel possibly found at Fukushima No. 1 — The Japan Times

” Tepco on Monday found what may be melted nuclear fuel debris that penetrated the reactor 2 pressure vessel at the Fukushima No. 1 plant.

Tokyo Electric Power Company Holdings Inc. said more analysis and investigation is needed to confirm that the black lumps detected in the reactor’s containment vessel are indeed fuel debris.

The steel pressure vessel houses the nuclear fuel rods and is set up inside the surrounding containment vessel.

“At this point, it’s difficult to clearly identify what they are,” said Yuichi Okamura, general manager of Tepco’s nuclear power and plant siting division, during an evening news conference at the utility’s Tokyo headquarters.

Video footage from Monday’s probe showed black lumps that looked like something that had melted and then congealed, sticking to parts of a steel grating area at the base of the containment vessel.

The material could be melted paint, cable covers or pipe wrappings, Okamura said.

Still, this is the first time Tepco has detected anything in any of the facility’s three wrecked reactors that might be melted fuel rods since the outbreak of the crisis in March 2011. Okamura described the finding as “valuable information.”

The location of the debris and what form it is in are critical to eventually recovering the fuel.

Tepco plans next month to send in a remote-controlled robot equipped with a thermometer and dosimeter. Analyzing the temperature and radiation level will help identify whether the lumps are fuel debris, Okamura said.

The fuel melted after the March 11, 2011, earthquake and tsunami knocked out Fukushima No. 1’s power supply, including the vital cooling functions.

It is believed that reactor No. 2’s fuel rods melted and penetrated the bottom of the 20-cm-thick pressure vessel and fell in to the containment vessel.

Tepco has been conducting an investigation to check the interior of the containment vessel since last week.

In a previous try, workers inserted a rod equipped with a small camera as a precursor to sending in the remote-controlled robot.

The first attempt turned up nothing of note, but the utility then tried a longer rod — 10.5 meters long — on Monday that could capture images of the area beneath the pressure vessel.

The video footage also showed that water droplets were falling, which Tepco said must be cooling water being injected into the damaged pressure vessel.

Reactor 2 is one of three reactors, including 1 and 3, that experienced fuel meltdowns. ”

by Kazuaki Nagata

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Fukushima disaster sways former advocate of nuclear power — Bloomberg

” The man blocking the world’s largest nuclear plant says he grew opposed to atomic energy the same way some people fall in love.

Previously an advocate for nuclear power in Japan, Ryuichi Yoneyama campaigned against the restart of the facility as part of his successful gubernatorial race last year in Niigata. He attributes his political U-turn to the “unresolved” 2011 Fukushima Dai-Ichi disaster and the lack of preparedness at the larger facility in his own prefecture, both owned by Tokyo Electric Power Co. Holdings Inc.

“Changing my opinion wasn’t an instant realization,” Yoneyama said in an interview. “It was gradual. As people say, you don’t know the exact moment you’ve fallen in love.”

Yoneyama won’t support the restart of the Kashiwazaki-Kariwa plant in Niigata until an investigation is complete into the chain of events that resulted in the triple meltdown at Fukushima, which he plans to visit Wednesday. While utilities don’t need approval of local authorities to restart plants, Japanese power companies are tradition-bound not to move ahead until they get their consent.

Local Opposition

Yoneyama, a 49-year-old doctor and native of Niigata, is one of the highest-profile local opponents pitted against a political establishment led by Prime Minister Shinzo Abe, which sees nuclear power as crucial for the country’s long-term energy security and environmental goals. Regulations and public opinion are keeping nearly all of Japan’s atomic stations shut almost six years after the accident at Fukushima, where the search has barely begun for fuel that burned through to the bottom of the reactors.

“If the local governor remains firmly opposed to the restart, it will be very difficult for the reactors to come back online,” said James Taverner, an analyst at IHS Markit Ltd. “In addition to the local government, building the support and trust of local residents is key.”

A Kyodo News poll on the day of Yoneyama’s October election showed about 64 percent of Niigata voters opposed the restart of Kashiwazaki-Kariwa, known popularly as KK. The restart of the facility was one of the key issues in the race to replace Governor Hirohiko Izumida, who was famous for his tough stance on Tokyo Electric. He unexpectedly announced in August that he wouldn’t seek a fourth term.

To the residents of the prefecture, Yoneyama was the candidate who would make nuclear safety a priority, while his main opponent gave off the vibe that he was a member of the nuclear restarts camp, the former governor said by e-mail.

Switching Sides

In last year’s gubernatorial race for the southern prefecture of Kagoshima, where Kyushu Electric Power Co. operates the Sendai nuclear plant, a three-term incumbent was defeated by an opponent campaigning to temporarily close the reactors. A district court last year barred Kansai Electric Power Co. from running two reactors at its Takahama station in western Japan only weeks after they’d been turned back on.

Yoneyama supported bringing back online Japan’s reactors during his unsuccessful bid in 2012 for a seat in Japan’s lower house. The country was being forced to spend more on fossil fuel imports after the disaster, so restarting the plants was needed to help the economy recover, he said at the time.

Though Yoneyama’s position switch helped secure his first electoral victory after four failed campaigns for the country’s legislature, nuclear opponents see him driven by more than political opportunism.

“I had my reservations about Yoneyama,” said Takehiko Igarashi, an official at the Niigata division of the anti-nuclear group Nakusou Genpatsu. “But after he was vetted and endorsed by the Japanese Communist Party and other smaller parties that have an anti-nuclear slant, I knew that I could trust him.”

evTokyo Electric and Abe’s government see restarting KK as one way for Japan’s biggest utility to boost profits and help manage its nearly 16 trillion yen ($139 billion) share of the Fukushima cleanup. Resuming reactors No. 6 and No. 7 will boost annual profits by as much as 240 billion, the utility has said.

The economic argument, however, is beginning to hold less sway, with Yoneyama saying the benefits to the local economy are ‘overstated.’ While the prefecture risks missing out on 1.1 billion yen a year in government support without the restart, that represents a small slice of the prefecture’s budget, which tops 1 trillion yen, according to Yoneyama.

Abe, a strong backer of atomic power, leads a government aiming for nuclear to account for as much as 22 percent of Japan’s energy mix by 2030, compared with a little more than 1 percent now.

While restart opponents like Yoneyama demand the government guarantee the safety of the reactors, they’ve also criticized evacuation and emergency response plans as inadequate.

In his first meeting with Tokyo Electric executives since taking office, Yoneyama earlier this month told Chairman Fumio Sudo and President Naomi Hirose that he won’t support KK’s restart until a new evacuation plan is drawn up using the results of a Fukushima investigation. Tepco will fully cooperate with the probe and stay in communication with the governor, the company said in response to a request for comment.
“Once I realized that the Fukushima disaster couldn’t be easily resolved, of course my opinion changed,” Yoneyama said. “If another accident occurs, overseas tourism will become a distant dream. Even Japanese may flee the country.” ”

by Stephen Stapczynski and Emi Urabe

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Only 13% of evacuees in 5 Fukushima municipalities have returned home as of January 2017 — The Mainichi

” FUKUSHIMA (Kyodo) — Only 13 percent of the evacuees from the 2011 Fukushima nuclear disaster in five municipalities in Fukushima Prefecture have returned home after evacuation orders were lifted, local authorities said Saturday.

Some residents who used to live in the cities of Tamura and Minamisoma, villages of Kawauchi and Katsurao, and the town of Naraha may be reluctant to return to their homes due to fear of exposing children to radiation, the authorities said.

The evacuation orders to residents in those municipalities were lifted partly or entirely from April 2014 through July 2016. As of January, about 2,500 people out of a combined population of around 19,460 registered as residents of those areas were living there.

Evacuation orders for four more towns and villages in Fukushima Prefecture are scheduled to be lifted this spring, but it is uncertain how many residents will return to those areas as well.

In the prefecture, eight municipalities are still subject to evacuation orders around the Fukushima Daiichi nuclear power plant due to high radiation levels. Three nuclear reactors at the plant melted down and the structures housing them were severely damaged by hydrogen gas explosions days after a massive earthquake and ensuing tsunami on March 11, 2011 knocked out electric power needed to run critical reactor cooling equipment. ”

by The Mainichi

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Plans to remove nuclear fuel at Fukushima delayed again — Reuters via Channel NewsAsia

” A plan to remove spent nuclear fuel from Tokyo Electric Power Co Holdings Inc’s Fukushima Daiichi nuclear plant hit by the March 2011 tsunami has been postponed again due to delays in preparation, the Nikkei business daily reported on Thursday.

Work is now set to begin in fiscal 2018 at the earliest, the Nikkei said.

Removal of the spent fuel from the No. 3 reactor was originally scheduled in the first half of fiscal 2015, and later revised to fiscal 2017 due to high levels of radioactivity around the facilities, the Japanese business daily reported.

The timeline has been changed again as it was taking longer than expected to decontaminate buildings and clean up debris, the news agency reported.

The report comes a few months after the Japanese government said in October the cost of cleaning up the Fukushima plant may rise to several billion dollars a year, adding that it would look into a possible separation of the nuclear business from the utility. ”

Reporting by Krishna V Kurup in Bengaluru, editing by Shounak Dasgupta, REUTERS

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NRA slows plan to reuse contaminated soil — SimplyInfo.org

” Japan’s Environment Ministry had a plan. They were going to solve the problem of the massive piles of radioactive soil but reusing it. One plan they described was using it as the base in roads. They didn’t provide much detail on how this would work or how it would not end up leaching contamination to the wider environment.

Japan’s nuclear regulator (NRA) is required to review any act by another agency that involves radiation exposures to the public. Now the NRA has requested a detailed plan before any review would begin. They want details about how this soil would be prevented from being used in residential areas or where children would be exposed.

This may have effectively put a stop to the Environment Ministry plan. Their goal appeared to be to declassify large amounts of contaminated soil and just make it go away however possible. NRA’s requirements may be too inconvenient to continue with that plan. ”

by SimplyInfo.org

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