Fukushima frozen wall status 2017; Unit 3 cover building installation — SimplyInfo.org

SimlyInfo.org shows a map of the current status of the frozen ice wall at Fukushima No. 1.

* * *

Read SimplyInfo.org’s article on the current construction of a cover building for Fukushima Daiichi’s Unit 3, which will hopefully allow for robotic removal of spent fuel.

 

NRA: Ice wall effects ‘limited’ at Fukushima nuclear plant — The Asahi Shimbun

” Citing “limited, if any effects,” the Nuclear Regulation Authority said a highly touted “frozen soil wall” should be relegated to a secondary role in reducing contaminated groundwater at the Fukushima No. 1 nuclear plant.

The government spent 34.5 billion yen ($292 million) to build the underground ice wall to prevent groundwater from mixing with radioactive water in four reactor buildings at the crippled plant.

But the NRA, Japan’s nuclear watchdog, concluded on Dec. 26 that the wall has been ineffective in diverting the water away from the buildings. It said that despite the low rainfall over the past several months, the amount of groundwater pumped up through wells outside the frozen wall on the seaside is still well above the reduction target.

It urged the plant operator, Tokyo Electric Power Co., to tackle the groundwater problem primarily with pumps, not the ice wall.

In response, TEPCO at the meeting said that by next autumn, it will double its capacity to pump up groundwater from the current 800 tons a day.

About 400 tons of groundwater enters the damaged reactor buildings each day and mixes with highly radioactive water used to cool melted nuclear fuel.

The ice wall project, compiled by the industry ministry in May 2013, was seen as a fundamental solution to this problem that has hampered TEPCO’s cleanup efforts since the triple meltdown in March 2011.

Some 1,568 frozen ducts were inserted 30 meters deep into the ground to circulate a liquid at 30 degrees below zero. The freezing process was supposed to have created a solid wall of ice that could block the groundwater.

TEPCO began freezing the wall on the seaside in March. It announced in the middle of October that the temperature at all measuring points in that area was below zero.

Before the frozen wall project, TEPCO had to pump up about 300 tons of contaminated water a day. The daily volume dropped to about 130 tons in recent weeks, but it was still well beyond the target of 70 tons.

Still, TEPCO boasted about the effectiveness of the ice wall at the meeting with the NRA on Dec. 26, saying, “We are seeing certain results.”

The NRA, however, said the results are limited at best.

Toyoshi Fuketa, an NRA commissioner, already warned TEPCO in October that it cannot expect the ice wall to be highly effective in containing the groundwater.

“Pumping up groundwater through wells should be the main player because it can reliably control the groundwater level,” Fuketa said at that time. “The ice wall will play a supporting role.”

That sentiment was echoed at the Dec. 26 meeting.

However, the NRA approved the utility’s plan to begin freezing dirt for a wall on the mountain side of the nuclear plant.

The NRA was previously concerned about risks posed by the new ice wall. If it totally blocked groundwater from the mountain side, the water level within the frozen soil near the reactors could become too low, allowing highly contaminated water inside the reactor buildings to flow out more rapidly.

The NRA urged TEPCO to delay work on the mountain side until the ice wall on the seaside portion proved effective.

But it reversed its stance, saying a sharp drop in the groundwater level is unlikely based on the ineffectiveness of the existing ice wall.

“The frozen wall on the mountain side will not be able to block groundwater because the wall on the seaside was also unable to do so,” Fuketa said. “It will not be very dangerous to freeze the wall on the mountain side as long as the work is carried out carefully.”

TEPCO will start the work to freeze the ducts at five sections as early as next year.

Masashi Kamon, professor emeritus of geotechniques at Kyoto University, expressed skepticism about continuing the ice wall project without a full scrutiny of the underground conditions.

“Soil around the tunnels for underground pipes must be hard to freeze,” he said. “TEPCO should find out the conditions of the very bottom of the ice wall by drilling at least one section. It is questionable to continue with the project without a review.” ”

by Kohei Tomida

source

For 6,000, the daily bus ride takes them to Fukushima plant — The Asahi Shimbun

” NARAHA, Fukushima Prefecture–Despite the predawn hour, few people are sleeping on a bus that steadily makes its way north on National Route 6.

Some passengers are planning for the work ahead. One is looking forward to chatting with his colleagues. And a few wonder if today will be the day when their annual radiation doses reach the safety limit.

Every day, buses like this take 6,000 workers to the Fukushima No. 1 nuclear power plant. And every day, the same buses take the exhausted and mostly sleeping workers back to their base at the Japan Football Village (J-Village) in Naraha.

Although the Fukushima plant is still decades away from being decommissioned, without this daily routine of the workers who toil amid an invisible danger, the situation at the site would be much more difficult.

407 Daily Bus Rides

One of them, the 49-year-old leader of a group of metal workers from Iwaki, Fukushima Prefecture, has been working at nuclear plants, including the Kashiwazaki-Kariwa power station in Niigata Prefecture, for nearly 20 years.

He was at the Fukushima No. 1 nuclear plant when the Great East Japan Earthquake and tsunami triggered the triple meltdown there in March 2011.

“Nobody can get close to the area where the melted nuclear fuel remains due to high radiation doses,” the man said. “Even if we could approach the area, we would have no way out if something happens. The situation is harsh.”

Those metal workers install tanks for the contaminated water that keeps accumulating at the plant.

Although there are plenty of empty seats, the young workers sit in front and the older workers take the back seats.

Thousands of workers are staying at temporary dormitories set up in J-Village, a soccer training complex.

Tokyo Electric Power Company Holdings Inc., operator of the nuclear plant, hired a local bus company to transport the workers to the plant because securing parking areas near the site has been difficult since the 2011 disaster.

The company provides 407 services a day to and from the plant. Each trip takes about 30 minutes.

The first shuttle bus departs from J-Village at 3:30 a.m., while the last bus leaves the Fukushima plant at 9:45 p.m.

In mid-November amid torrential rain, one bus picked up a man taking shelter under the eaves of a bus stop.

He said he is in charge of managing data related to radiation doses of fittings and other equipment at the plant.

“We have many different types of work here,” the man proudly said.

Also on the way to the nuclear plant, a 53-year-old employee of a security company was thinking about personnel distribution.

Like other workers there, security guards must be replaced when their annual radiation doses reach a certain level set by the government.

He said he has difficulties making ends meet with a limited number of guards who have knowledge about radiation.

Suddenly, the man’s cellphone rings, and the caller orders the deployment of additional security guards to the plant.

A 52-year-old TEPCO employee was on the way to the nearby Fukushima No. 2 nuclear power plant to provide a safety training program for workers, many of whom are victims of the triple disaster.

“I want to convey to workers how precious their lives are and how important safety is in a way that doesn’t make me sound hypocritical,” the employee said.

The triple meltdown has been called a “man-made disaster” caused by the failure of both TEPCO’s management and the government’s regulatory authorities.

The TEPCO employee will use props, such as a ladder, and pretend to be a worker to explain dangerous cases at the No. 1 plant.

Premium Seats

On the trip back to J-Village, a different atmosphere exists on the bus.

Although dazzling sunlight shines through the windows and stunning views of the ocean are available, most of the workers are fast asleep in their wrinkled uniforms.

“Few people stay awake. I don’t even switch on the radio. They must be tired after their work,” said Nobuyuki Kimura, 52, who has driven the shuttle bus for one-and-a-half years.

In Kimura’s bus that departed the plant at 2:30 p.m., all 50 seats and some of the auxiliary seats were filled. The few passengers who stayed awake remained quiet.

By early evening, fewer workers boarded the bus at the plant.

Window seats at the back of the bus are desirable on all rides because they have an enough room for the seats to recline, allowing passengers to cross their legs.

A 21-year-old worker from Iwaki went for a window seat at the back after standing at the front of a line waiting for the bus.

“I can relax sitting here. This is the premium seat,” said the man who collects waste materials, such as boots and socks, at the site.

Although he works in protective gear in an area with high radiation levels, he said he has never thought about quitting his job.

He said he became fed up with school as a junior high school student, and did not bother going to senior high school.

At the age of 18, he joined his current company, and his first assignment was at the Fukushima No. 1 plant.

“I became acquaintances with more and more people. It’s fun to speak with people at work,” he said.

Through his work at the nuclear plant, his weight has dropped from 115 kilograms to 93 kg.

Thirty to 40 years are needed to decommission the Fukushima No. 1 plant, according to the mid- and-long-term roadmap compiled by the government and TEPCO.

To reduce the groundwater flowing into the buildings housing the No. 1 to No. 4 reactors, TEPCO installed coolant pipes this year to create an underground frozen soil wall to divert the water into the ocean.

TEPCO announced in October that the ice wall on the sea side was nearly frozen, but groundwater is believed to be seeping through it.

The utility plans to start removing spent fuel from the No. 3 reactor building in fiscal 2017. It also has plans to begin the daunting task of removing the melted fuel from the No. 1 to No. 3 reactor containment vessels in 2021.

However, extremely high radiation levels have prevented workers from approaching and understanding the condition of the melted fuel. The removal method has yet to be decided.

The estimated cost of work for decommissioning and dealing with the contaminated water has ballooned to 8 trillion yen ($68.1 billion). ”

by Aya Nagatani

source

Tepco admits success of Fukushima ice wall still unknown — The Japan Times

” Tokyo Electric Power Holdings Inc. and the government bet big on an underground ice wall as a key measure to battle the tainted water issue at the crippled Fukushima No. 1 nuclear plant.

But whether the ¥35 billion gambit funded by the government is working to block the inflow of groundwater remains unclear even six months after the utility started freezing an area of underground soil.

Tepco said it needs more time to judge whether the system is working. But the Nuclear Regulation Authority, Japan’s nuclear watchdog, appears skeptical on the effectiveness of the 1.5-km-long wall that encircles reactor buildings 1 to 4, asking Tepco to deal with the issue but without counting on it.

So far Tepco has finished freezing the east side of the ice wall — albeit with delays caused by severe typhoon-driven rains — and 95 percent of the west side but has yet to get the NRA’s approval to freeze the rest of it.

“It’s really unfortunate and I am very sorry” for not being able to provide an assessment of the ice wall, Naohiro Masuda, who heads Tepco’s decommissioning project, told a news conference Thursday.

Masuda said in August that Tepco would be able to provide an assessment of the effectiveness of the ice wall in September, and that the utility would have finished freezing the east side by then.

But Masuda said unexpected heavy rain during recent typhoons melted some parts of the structure.

Masuda said workers have since repaired the damage and finished freezing the east side 100 percent. But he declined to say when the assessment will be released.

The purpose of the ice wall is to block groundwater before it can enter the reactor buildings, which are located between nearby mountains and the ocean.

To do this, Tepco pumps groundwater that has flowed west to east toward five wells near the ocean, back into the reactors to cool them.

If the wall succeeds, the water being pumped from the ocean wells should reduce to about 70 tons each day, from hundreds of tons, according to Tepco. The daily level was between 600-1,200 tons in September, which Tepco attributed to heavy rains.

About 180 tons of groundwater a day seeps into the reactor buildings through cracks or holes and is mixed with contaminated water inside, causing the amount of tainted water at the plant to increase daily.

Currently, about 68,000 tons of tainted water is stored there but the risk remains that it could leak if another powerful quake hits near the facility.

For Tepco, the success of the ice wall is fundamental to achieve its next major goal of removing the contaminated water flooding the basement floors of the reactor buildings.

The utility plans to remove the water by 2020, but believes it can speed up the process by two years if the underground wall works.

The NRA, however, remains unconvinced.

“(Tepco) needs to come up with measures that do not rely on the ice wall and complete the removal of the tainted water from the building by 2020,” Toyoshi Fuketa, deputy NRA chairman, told Tepco officials at a panel meeting Wednesday.

During the meeting, Tepco expressed its intention to freeze the entire west side of the wall.

But Fuketa said, “That’s out of discussion,” since it was still unclear whether the east side was effectively blocking groundwater.

Among the NRA’s concerns is that completely blocking the groundwater on the west side might reduce the groundwater level below the tainted flooded water line in the reactor buildings, which would allow tainted water to leak out.

But as the wall appears to have done little to reduce the amount of groundwater pumped daily, the NRA ordered Tepco to come up with alternative measures.

The NRA has suggested that Tepco strengthen the pumping capability of wells around the reactor buildings to collect the groundwater before it can seep inside.

Tepco said at the Wednesday meeting that it will still be able to finish the removal of tainted water in the buildings by 2020 without the ice wall. ”

by Kazuaki Nagata

source

Typhoon rain raises tainted Fukushima plant groundwater to surface — The Japan Times

” Heavy rain brought by Typhoon Malakas caused contaminated groundwater to rise to ground level at the radiation-hit Fukushima No. 1 nuclear plant Tuesday night, raising fears of tainted water flooding out to the plant’s port area, its operator said.

Tokyo Electric Power Company Holdings Inc. said in a press release that plant workers are doing their utmost to pump up tainted groundwater at the Fukushima compound, while trying to measure the level of radioactive substances contained in the water.

Under normal circumstances, groundwater taken from wells around the damaged reactor buildings at the Fukushima plant is filtered and stored in numerous tanks built on the compound.

Shortly before 10 p.m. Tuesday, groundwater reached the surface level at an observation well near the seawall at the power plant’s port, and at 11:30 p.m. Tuesday, groundwater stood at 3 cm above the surface level, Tepco said.

The well has a far higher wall and the ground around it is paved, the company said, playing down the possibility that any water flowed out of the well.

By 9 a.m. Wednesday, the water level had dropped to 3 cm below the surface.

Meanwhile, some rainwater may have flowed directly into the port before seeping underground, according to the company.

Tepco will continue pumping groundwater around the seawall, located near the damaged No. 1 to No. 4 reactors, and carry out close examinations of water inside the port, the company said.

In order to curb the flow of groundwater into the sea, the company has covered the seawall with water shields and carries out groundwater pumping operations.

Typhoon Malakas itself was downgraded to an extratropical depression at around 9 p.m. Tuesday as it moved along the coast of the Tokai region and swayed toward the Pacific. It was initially forecast to hit the Kanto region in the early hours of Wednesday.

The previous typhoon, Lionrock, earlier this month killed at least 17 people. Before Lionrock, two typhoons had claimed at least two lives in the northeast. ”

by Jiji staff report

source

Japan’s ‘ice wall’ a problematic sticking plaster at Fukushima — The Nation

” Three years ago, Japanese Prime Minister Shinzo Abe helped Tokyo win its bid to host the 2020 Olympics by declaring that the situation at the crisis-wracked Fukushima Daiichi Nuclear Power Station was under control.

That has turned out to be not quite true.

Japan has yet to resolve a crisis at the plant that has lingered since its 2011 nuclear disaster: Groundwater has continued to flow into the basement of the highly contaminated facility. Even worse, some of that has then flown back into the Pacific Ocean.

The problem has hindered a decommission process that was already set to take decades.

In order to reduce the flow, Tokyo has built a huge underground ice wall around reactor buildings. But the 1.5-kilometre-long and 30-metre-deep barrier has not fully frozen, even though it was supposed to become operational around July. The unprecedented project cost taxpayers about 35 billion yen (Bt11.9 billion).

“They have kept saying they can. But they can’t,” former prime minister Junichiro Koizumi told a recent news conference.

Abe’s “under control” remark was “a lie”, Koizumi said. “I’m just wondering how he can say such a thing.”

The phrase “ice wall” is a bit of a misnomer. Officially called the Land-side Impermeable Wall, the coolant-filled barrier will consist of a layer of soil kept frozen by underground pipes, surrounding reactors 1 to 4.

The ice wall project “has stayed on track”, said Tasuhiro Yamagishi, a spokesman for operator Tokyo Electric Power. He added 99 per cent of the wall closest to the sea has been frozen.

The operator, however, acknowledged this month that rainfall from recent typhoons caused melting at two sections of the ice wall in mid-August, leading toxic water to leak from around the plant.

Nonetheless, no contaminated water flowed into the sea, the operator said.

Such statements have not convinced Hisataka Yamazaki, a member of the Tokyo-based Depleted Uranium Centre Japan.

He says he believed there was some leakage, saying the incident was “very serious”.

“As the Fukushima area was not hard-hit by the storms, the incident gave rise to fears that even heavier rain could cause more melting, allowing more toxic water to flow into the nearby Pacific Ocean,” Yamazaki said.

“At this moment, we are looking into the matter and considering what is the best way” to avoid a recurrence, Yamagishi said.

“We know that temporary measures would not work,” said Hideyuki Ban, co-director at Citizens’ Nuclear Information Centre in Tokyo.

“I believe we can say the project has failed.”

In June 2014, the operator started to install equipment for the wall at the plant and completed the work in February. It started to freeze the dirt at the end of March.

“From the beginning, there was doubt whether the wall could be fully frozen,” Ban said.

The water crisis could prolong the decommissioning period, he added.

The Fukushima plant suffered meltdowns at three of its six reactors after a tsunami swept through the complex in March 2011. The operator continues to inject water into the three reactors to keep them cool.

About 100,000 residents have yet to return to their homes near the plant due to radiation contamination.

Koizumi said Japan’s worst nuclear accident led him to revisit nuclear energy issues and came to realise that what experts said about nuclear energy being safe, cheap and clean was “all lies”.

I was ashamed of having believed such lies,” said Koizumi, who served as premier between 2001 and 2006.

Koizumi, who is now an anti-nuclear campaigner, said: “While Tokyo Electric and other power companies are saying they give the highest priority to safety, they actually place priority on profits and put safety on the back-burner.” “

by Takehiko Kambayashi

source