What to do with radioactive water from Fukushima — VOA Learning English

” Japanese officials are trying to decide what to do with thousands of tons of radioactive water from the damaged Fukushima nuclear power plant.

More than six years have passed since a powerful earthquake and tsunami severely damaged the power plant.

Some parts of cleanup efforts have gone well. People can now work in the area although they take special measures to avoid overexposure to radioactive substances.

The water remains a big problem however. Currently, the water is being stored in 900 large tanks near the nuclear center.

Conflicting opinions between two groups have kept Japanese officials from doing anything about the water.

Radiation experts advise the government to slowly release the water into the Pacific Ocean. They note that special treatment has removed the radioactivity from the water except for tritium, a radioactive form of hydrogen. The experts say tritium is safe in small amounts.

But local fishermen oppose the release of the water into the sea. They say people will not buy fish from waters near Fukushima if the water is released.

The fishermen lost their livelihoods for a long time after the disaster. Local fisheries are slowly recovering.

Fumio Haga fishes about 50 kilometers from the power plant. He said, “People would shun Fukushima fish again as soon the water is released.”

Fukushima disaster affected land and sea

The disaster was both deadly and had long-lasting environmental and economic effects.

An extremely powerful magnitude 9.0 earthquake struck off the coast of Japan on March 11, 2011. The quake caused deadly tsunami waves on the country’s northeastern coast. More than 18,000 people were killed.

The earthquake and waves caused the electricity to go out in many places including Fukushima. As a result, the cooling system failed in three of the six nuclear reactors which caused the nuclear fuel to overheat and partly melt structures in the power plant.

Radiation entered the air and contaminated water flowed into the sea.

That event hurt the livelihoods of people throughout the area. Although there are about 1,000 fishermen in the area today, only half still fish and they go out only two times a week because demand is low.

To be sold, the fish have to meet, what might be, the world’s most demanding requirements. Laboratory workers at Onahama test the fishermen’s catch, recording who caught the fish and where. And fish from the area is sold with official “safe” stickers.

Fifteen months after the disaster in 2012, only three kinds of fish could pass the safety inspection. Now the number has increased to over 100.

Yoshiharu Nemoto is a researcher at the Onahama test station. He said the fish may contain less than half of the radioactive cesium level permitted under Japan’s national standard and one-twelfth of the U.S. or European Union limit.

But consumers have not heard that message.

Over the years, fewer Japanese consumers avoid fish products from waters near Fukushima. But a study by Japan’s Consumer Agency in October found that 20 percent still do. The study found that consumers were more likely to pay attention to information about possible bad health results than to facts about radiation and safety standards.

Naoya Sekiya is an expert on social research and social psychology. He said the water from the nuclear power center should not be released until the public is well-informed about the facts.

“A release only based on scientific safety, without addressing the public’s concerns, cannot be tolerated in a democratic society,” he said. He said a release when the public is not prepared would only make things worse.

Kikuko Tatsumi is a representative of a consumer group and serves on a government expert panel with Sekiya. The group has been trying to decide what to do with the water for longer than one year.

Tatsumi said the delay in making a decision may be increasing concerns among the public. Many people believe the water is stored because it is dangerous and they think Fukushima fish are not available because they are not safe to eat.

Water from the center is a continuing problem

The Associated Press reports the amount of radioactive water at Fukushima is growing by 150 tons a day. This is because new water is used to cool the damaged reactors and ground water also enters the reactor area through cracks.

The water is a costly problem for the utility company Tokyo Electric Power Co, or TEPCO, which owns Fukushima. Last year, another group of government experts recommended that TEPCO should dilute the water by about 50 times and release it into the sea over time. The process could take 10 years to complete.

The new chairman at TEPCO, Takashi Kawamura, caused a strong reaction in the fishing community in April. He had expressed support for releasing the water.

But after strong opposition, the company withdrew the idea and said it had no plans for an immediate release and can continue storing water until 2020.

So, the problem continues, and the amount of radioactive water at Fukushima is growing.

I’m Mario Ritter. ”

 Mari Yamaguchi reported this story for AP. Mario Ritter adapted it with additional materials for VOA Learning English. Hai Do was the editor. 

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Fukushima dome roof takes shape, but radiation remains high — The Asahi Shimbun

” High radiation levels are still limiting recovery work at the Fukushima No. 1 nuclear plant, a stark reality that reporters saw firsthand when they observed efforts to remove risk factors there.

Media representatives were invited into the plant in early December to see construction work, with the building of a domed roof over the No. 3 reactor building as the main focus.

However, they were only allowed to stay on top of the roof for 20 minutes due to high radiation levels.

The roof is being put together directly above the storage pool for spent fuel. The dome is designed to prevent the spewing of radioactive materials when the fuel is actually removed from the pool.

The original roof of the No. 3 reactor building was severely damaged by a hydrogen explosion in the days following the March 11, 2011, Great East Japan Earthquake and tsunami, which led to the crippling of the Fukushima No. 1 plant.

Spent fuel still remains in the storage pools located on the top floors of the No. 1 to No. 3 reactor buildings.

Plans call for removing the spent fuel first from the No. 3 reactor building.

Although the dome will help prevent the spread of radioactive materials, building parts and other debris as well as some equipment have still not been completely removed from the storage pool, which holds 566 fuel rods.

The collapsed roof and walls were removed to allow for the construction of the domed roof, which began in the summer. The domed roof is about 17 meters high, and a crane was also installed under it in November.

Plans call for the removal of the spent fuel from the No. 3 building to begin in the middle of the next fiscal year.

Internal radiation exposure levels were measured before media representatives headed to the No. 3 reactor building. They were also required to don protective clothing as well as a partial face mask covering the mouth and nose from about 100 meters from the building.

Radiation levels close to the building were 0.1 millisieverts per hour.

An elevator installed into the scaffolding next to the reactor building took the media representatives to the roof, which had been covered with metal plates.

The so-called operating floor looked like any other newly constructed building roof, a sharp contrast to the twisted metal parts that covered the building shortly after the nuclear accident.

Tokyo Electric Power Co., the plant’s operator, captured video footage from within the reactors for the first time in July. Debris that appears to be melted nuclear fuel was found in various parts of the containment vessel.

To the south of the No. 3 reactor building stands the No. 4 reactor building, from where all the spent nuclear fuel has been removed.

To the north is the No. 2 reactor building, which avoided a hydrogen explosion. Beyond the building, cranes and other large equipment are working in preparation for the removal of debris from the No. 1 reactor building.

TEPCO officials cautioned media representatives about standing too long right next to the storage pool, which could be seen located about six meters below the roof. Debris was found within the pool while insulating material floated on the pool surface.

The radiation level near the pool was 0.68 millisieverts per hour. While that was a major improvement from the 800 millisieverts per hour recorded in the immediate aftermath of the nuclear accident close to seven years ago, it was still too high to allow for a stay of longer than 20 minutes. ”

by Chikako Kawahara, The Asahi Shimbun

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Image shows extent of damage to reactor at Fukushima plant — The Asahi Shimbun

” An image taken by an underwater robot shows corroded tubes stuck in a hole created by melted fuel in the pressure vessel of the No. 3 reactor at the Fukushima No. 1 nuclear plant.

The image offers clues on the extent of the damage caused when fuel rods in the reactor melted through the bottom of the pressure vessel after the disaster at the nuclear plant unfolded in March 2011.

Tokyo Electric Power Co., operator of the plant, sent the specially designed robot into the reactor in July. The company earlier released images taken by the robot that showed what is believed to be melted nuclear fuel debris.

In the image released on Nov. 30, TEPCO identified the severely corroded and damaged tubes as parts of a device used to move control rods. Normally, that device is located inside the pressure vessel.

TEPCO on Nov. 30 also said it would conduct another study inside of the containment vessel of the No. 2 reactor at the plant in January. The containment vessel surrounds the pressure vessel.

A telescopic stick more than 10 meters long and equipped with a camera will be used for the survey. ”

by The Asahi Shimbun

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Japan still at a stalemate as Fukushima’s radioactive water grows by 150 tons a day — The Japan Times

” More than six years after a tsunami overwhelmed the Fukushima No. 1 nuclear power plant, Japan has yet to reach consensus on what to do with a million tons of radioactive water, stored on site in around 900 large and densely packed tanks that could spill should another major earthquake or tsunami strike.

The stalemate is rooted in a fundamental conflict between science and human nature.

Experts advising the government have urged a gradual release to the Pacific Ocean. Treatment has removed all the radioactive elements except tritium, which they say is safe in small amounts. Conversely, if the tanks break, their contents could slosh out in an uncontrolled way.

Local fishermen are balking. The water, no matter how clean, has a dirty image for consumers, they say. Despite repeated tests showing most types of fish caught off Fukushima are safe to eat, diners remain hesitant. The fishermen fear any release would sound the death knell for their nascent and still fragile recovery.

“People would shun Fukushima fish again as soon as the water is released,” said Fumio Haga, a drag-net fisherman from Iwaki, a city about 50 kilometers (30 miles) down the coast from the nuclear plant.

And so the tanks remain.

Fall is high season for saury and flounder, among Fukushima’s signature fish. It was once a busy time of year when coastal fishermen were out every morning.

Then came March 11, 2011. A magnitude 9 offshore earthquake triggered a tsunami that killed more than 18,000 people along the coast. The quake and massive flooding knocked out power for the cooling systems at the Fukushima nuclear plant. Three of the six reactors had partial meltdowns. Radiation spewed into the air, and highly contaminated water ran into the Pacific.

Today, only about half of the region’s 1,000 fishermen go out, and just twice a week because of reduced demand. They participate in a fish testing program.

Lab technicians mince fish samples at Onahama port in Iwaki, pack them in a cup for inspection and record details such as who caught the fish and where. Packaged fish sold at supermarkets carry official “safe” stickers.

Only three kinds of fish passed the test when the experiment began in mid-2012, 15 months after the tsunami. Over time, that number has increased to about 100.

The fish meet what is believed to be the world’s most stringent requirement: less than half the radioactive cesium level allowed under Japan’s national standard and one-twelfth of the U.S. or EU limit, said Yoshiharu Nemoto, a senior researcher at the Onahama testing station.

That message isn’t reaching consumers. A survey by the Consumer Affairs Agency in October found that nearly half of Japanese weren’t aware of the tests, and that consumers are more likely to focus on alarming information about possible health impacts in extreme cases, rather than facts about radiation and safety standards.

Fewer Japanese consumers shun fish and other foods from Fukushima than before, but 1 in 5 still do, according to the survey. The coastal catch of 2,000 tons last year was 8 percent of pre-disaster levels. The deep-sea catch was half of what it used to be, though scientists say there is no contamination risk that far out.

Naoya Sekiya, a University of Tokyo expert on disaster information and social psychology, said that the water from the nuclear plant shouldn’t be released until people are well-informed about the basic facts and psychologically ready.

“A release only based on scientific safety, without addressing the public’s concerns, cannot be tolerated in a democratic society,” he said. “A release when people are unprepared would only make things worse.”

He and consumer advocacy group representative Kikuko Tatsumi sit on a government expert panel that has been wrestling with the social impact of a release and what to do with the water for more than a year, with no sign of resolution.

Tatsumi said the stalemate may be further fueling public misconception: Many people believe the water is stored because it’s not safe to release, and they think Fukushima fish is not available because it’s not safe to eat.

The amount of radioactive water at Fukushima is still growing, by 150 tons a day.

The reactors are damaged beyond repair, but cooling water must be constantly pumped in to keep them from overheating. That water picks up radioactivity before leaking out of the damaged containment chambers and collecting in the basements.

There, the volume of contaminated water grows, because it mixes with groundwater that has seeped in through cracks in the reactor buildings. After treatment, 210 tons is reused as cooling water, and the remaining 150 tons is sent to tank storage. During heavy rains, the groundwater inflow increases significantly, adding to the volume.

The water is a costly headache for Tokyo Electric Power Company Holdings Inc., the utility that owns the plant. To reduce the flow, it has dug dozens of wells to pump out groundwater before it reaches the reactor buildings and built an underground “ice wall” of questionable effectiveness by partially freezing the ground around the reactors.

Another government panel recommended last year that the utility, known as Tepco, dilute the water up to about 50 times and release about 400 tons daily to the sea — a process that would take almost a decade to complete. Experts note that the release of tritiated water is allowed at other nuclear plants.

Tritiated water from the 1979 Three Mile Island accident in the United States was evaporated, but the amount was much smaller, and still required 10 years of preparation and three more years to complete.

A new chairman at Tepco, Takashi Kawamura, caused an uproar in the fishing community in April when he expressed support for moving ahead with the release of the water.

The company quickly backpedaled, and now says it has no plans for an immediate release and can keep storing water through 2020. Tepco says the decision should be made by the government, because the public doesn’t trust the utility.

“Our recovery effort up until now would immediately collapse to zero if the water is released,” Iwaki abalone farmer Yuichi Manome said.

Some experts have proposed moving the tanks to an intermediate storage area, or delaying the release until at least 2023, when half the tritium that was present at the time of the disaster will have disappeared naturally. ”

by Mari Yamaguchi, The Japan Times

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GE faces lawsuit over role in Fukushima nuclear disaster — Boston Globe

” A group of Japanese businesses and doctors sued General Electric Co. in Boston federal court on Friday, claiming the industrial giant was reckless and negligent in its design of the reactors and related systems at the core of the Fukushima nuclear disaster in 2011.

The plaintiffs claim Boston-based GE knowingly used a reactor design at the Fukushima Daiichi Nuclear Power Plant that would fail to protect against the possible threat of earthquakes and tsunamis, a natural risk in that area.

The plaintiffs are seeking class-action status for businesses in the area that suffered economic damage as a result of the disaster, which displaced as many as 150,000 people.

Among other things, the lawsuit claims GE and its partners lowered a protective cliff by more than 60 feet, placing the plant and all six of its GE-designed reactors closer to the Pacific Ocean and in the path of the severe tsunami that struck on March 11, 2011.

Afte the tsunami hit, three GE-designed reactors suffered from “entirely foreseeable flooding and resulting nuclear meltdowns,” causing the release of radioactive matter into the area surrounding the plant, according to the lawsuit. The plaintiffs are essentially blaming GE for defective reactor design as well as for not putting in place enough safeguards to prevent the spread of radiation once the Fukushima plant was breached.

A GE spokesman said the company continues to offer sympathy for those affected by the earthquake and tsunami of 2011.

“The Japanese government and other investigative bodies long ago concluded that the Fukushima nuclear accident was caused by the tsunami, and the resulting loss of seawater pumps and all electrical power, not reactor design,” he said. “We believe these claims can and should be addressed under Japan’s nuclear compensation law, which provides relief for persons impacted by these events.” ”

by Jon Chesto, Boston Globe

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Six years after Fukushima, robots finally find reactors’ melted uranium fuel — The New York Times

” FUKUSHIMA DAIICHI NUCLEAR POWER PLANT, Japan — Four engineers hunched before a bank of monitors, one holding what looked like a game controller. They had spent a month training for what they were about to do: pilot a small robot into the contaminated heart of the ruined Fukushima nuclear plant.

Earlier robots had failed, getting caught on debris or suffering circuit malfunctions from excess radiation. But the newer version, called the Mini-Manbo, or “little sunfish,” was made of radiation-hardened materials with a sensor to help it avoid dangerous hot spots in the plant’s flooded reactor buildings.

The size of a shoe box, the Manbo used tiny propellers to hover and glide through water in a manner similar to an aerial drone.

After three days of carefully navigating through a shattered reactor building, the Manbo finally reached the heavily damaged Unit 3 reactor. There, the robot beamed back video of a gaping hole at the bottom of the reactor and, on the floor beneath it, clumps of what looked like solidified lava: the first images ever taken of the plant’s melted uranium fuel.

The discovery in July at Unit 3, and similar successes this year in locating the fuel of the plant’s other two ruined reactors, mark what Japanese officials hope will prove to be a turning point in the worst atomic disaster since Chernobyl.

The fate of the fuel had been one of the most enduring mysteries of the catastrophe, which occurred on March 11, 2011, when an earthquake and 50-foot tsunami knocked out vital cooling systems here at the plant.

Left to overheat, three of the six reactors melted down. Their uranium fuel rods liquefied like candle wax, dripping to the bottom of the reactor vessels in a molten mass hot enough to burn through the steel walls and even penetrate the concrete floors below.

No one knew for sure exactly how far those molten fuel cores had traveled before desperate plant workers — later celebrated as the “Fukushima Fifty” — were able to cool them again by pumping water into the reactor buildings. With radiation levels so high, the fate of the fuel remained unknown.

As officials became more confident about managing the disaster, they began a search for the missing fuel. Scientists and engineers built radiation-resistant robots like the Manbo and a device like a huge X-ray machine that uses exotic space particles called muons to see the reactors’ innards.

Now that engineers say they have found the fuel, officials of the government and the utility that runs the plant hope to sway public opinion. Six and a half years after the accident spewed radiation over northern Japan, and at one point seemed to endanger Tokyo, the officials hope to persuade a skeptical world that the plant has moved out of post-disaster crisis mode and into something much less threatening: cleanup.

“Until now, we didn’t know exactly where the fuel was, or what it looked like,” said Takahiro Kimoto, a general manager in the nuclear power division of the plant’s operator, Tokyo Electric Power Co., or Tepco. “Now that we have seen it, we can make plans to retrieve it.”

Tepco is keen to portray the plant as one big industrial cleanup site. About 7,000 people work here, building new water storage tanks, moving radioactive debris to a new disposal site, and erecting enormous scaffoldings over reactor buildings torn apart by the huge hydrogen explosions that occurred during the accident.

Access to the plant is easier than it was just a year ago, when visitors still had to change into special protective clothing. These days, workers and visitors can move about all but the most dangerous areas in street clothes.

A Tepco guide explained this was because the central plant grounds had been deforested and paved over, sealing in contaminated soil.

During a recent visit, the mood within the plant was noticeably more relaxed, though movements were still tightly controlled and everyone was required to wear radiation-measuring badges. Inside a “resting building,” workers ate in a large cafeteria and bought snacks in a convenience store.

At the plant’s entrance, a sign warned: “Games like Pokemon GO are forbidden within the facility.”

“We have finished the debris cleanup and gotten the plant under control,” said the guide, Daisuke Hirose, a spokesman for Tepco’s subsidiary in charge of decommissioning the plant. “Now, we are finally preparing for decommissioning.”

In September, the prime minister’s office set a target date of 2021 — the 10th anniversary of the disaster — for the next significant stage, when workers begin extracting the melted fuel from at least one of the three destroyed reactors, though they have yet to choose which one.

The government admits that cleaning up the plant will take at least another three to four decades and tens of billions of dollars. A $100 million research center has been built nearby to help scientists and engineers develop a new generation of robots to enter the reactor buildings and scoop up the melted fuel.

At Chernobyl, the Soviets simply entombed the charred reactor in concrete after the deadly 1986 accident. But Japan has pledged to dismantle the Fukushima plant and decontaminate the surrounding countryside, which was home to about 160,000 people who were evacuated after accident.

Many of them have been allowed to return as the rural towns around the plant have been decontaminated. But without at least starting a cleanup of the plant itself, officials admit they will find it difficult to convince the public that the accident is truly over.

They also hope that beginning the cleanup will help them win the public’s consent to restart Japan’s undamaged nuclear plants, most of which remain shut down since the disaster.

Tepco and the government are treading cautiously to avoid further mishaps that could raise doubts that the plant is under control.

“They are being very methodical — too slow, some would say — in making a careful effort to avoid any missteps or nasty surprises,” said David Lochbaum, director of the nuclear safety project at the Union of Concerned Scientists, who was a co-author of a book on the disaster.

“They want to regain trust. They have learned that trust can be lost much quicker than it can be recovered.”

To show the course followed by the Manbo, Tepco’s Mr. Hirose guided me inside the building containing the undamaged Unit 5 reactor, which is structurally the same as two of the destroyed reactors.

Mr. Hirose pointed toward the spot on a narrow access ramp where two robots, including one that looked like a scorpion, got tangled in February by debris inside the ruined Unit 2.

Before engineers could free the scorpion, its monitoring screen faded to black as its electronic components were overcome by radiation, which Tepco said reached levels of 70 sieverts per hour. (A dose of one sievert is enough to cause radiation sickness in a human.)

Mr. Hirose then led me underneath the reactor, onto what is called the pedestal.

The bottom of the reactor looked like a collection of huge bolts — the access points for control rods used to speed up and slow down the nuclear reaction inside a healthy reactor. The pedestal was just a metal grating, with the building’s concrete floor visible below.

“The overheated fuel would have dropped from here, and melted through the grating around here,” Mr. Hirose said, as we squatted to avoid banging our heads on the reactor bottom. The entire area around the reactor was dark, and cluttered with pipes and machinery.

To avoid getting entangled, the Manbo took three days to travel some 20 feet to the bottom of Unit 3.

To examine the other two reactors, engineers built a “snake” robot that could thread its way through wreckage, and the imaging device using muons, which can pass through most matter. The muon device has produced crude, ghostly images of the reactors’ interiors.

Extracting the melted fuel will present its own set of technical challenges, and risks.

Engineers are developing the new radiation-resistant robots at the Naraha Remote Technology Development Center. It includes a hangar-sized building to hold full-scale mock-ups of the plant and a virtual-reality room that simulates the interiors of the reactor buildings, including locations of known debris.

“I’ve been a robotic engineer for 30 years, and we’ve never faced anything as hard as this,” said Shinji Kawatsuma, director of research and development at the center. “This is a divine mission for Japan’s robot engineers.” “

by Martin Fackler, The New York Times

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