TEPCO simulates release of Fukushima wastewater

April 6, 2020

Tokyo Electric Power Company has made public a simulation showing the flow of radioactive wastewater released into the ocean from the damaged Fukushima Daiichi nuclear plant. TEPCO says winds and tides will spread the wastewater in an elongated shape along the coastline.

The Japanese government has been looking into ways to dispose of the roughly 1.2 million tons of wastewater accumulated at the plant, which contains approximately 860 trillion becquerels of tritium.

TEPCO’s simulation estimated the area of ocean that would contain more than 1 becquerel of radioactive materials per liter.

The simulation shows that when water containing 100 trillion becquerels of radioactive materials is released each year, the area would be 2 kilometers offshore from the plant and stretch 30 kilometers from north to south.

When wastewater with 22 trillion becquerels of radioactive materials is released per year, it would spread 700 meters from shore and stretch 3 kilometers from north to south.

A government panel said in a report released in February that releasing diluted radioactive water into the sea or air are realistic options. The head of the International Atomic Energy Agency expressed some understanding for the plan. But the proposal drew opposition from local fishermen and others.

TEPCO has yet to show its simulation of wastewater released into the air.

https://www3.nhk.or.jp/nhkworld/en/news/20200406_03/

April 24, 2020 Posted by dunrenard | Fukushima 2020 | Fukushima Daiichi, Radioactive Water, Sea release | Leave a comment

Tepco to pursue its radioactive water sea release plan

Tepco to pursue its radioactive water sea release plan and “Tepco also plans to use social media to counter rumors that exposure to radiation from the released water is harmful.”

Plan to dispose of Fukushima wastewater drafted

March 24, 2020

NHK has learned that Tokyo Electric Power Company, or TEPCO, has drafted a plan for disposing of radioactive wastewater stored at the troubled Fukushima Daiichi nuclear power plant.

Water used to cool molten nuclear fuel from the 2011 accident is treated to remove most radioactive material. But tritium and other substances remain in the water, a huge amount of which is stored in about 1,000 large tanks.

A government panel last month compiled a report that says releasing diluted radioactive wastewater into the sea or air are realistic options.

TEPCO’s plan for doing so would involve diluting the wastewater with seawater, aiming for a tritium level of one-fortieth that allowed by national regulation.

The firm would gradually release the diluted water over about 30 years, taking into consideration the amount of similar water released at other nuclear plants.

TEPCO would also test treating the wastewater again to further remove other radioactive materials.

The utility is to explain the plan to local officials and residents in Fukushima Prefecture. People in the local fishery and tourism industries oppose releasing the water into the ocean.

https://www3.nhk.or.jp/nhkworld/en/news/20200324_42/

Tanks storing contaminated water at the Fukushima No. 1 nuclear power plant in February

Tepco may take 30 years to release Fukushima No. 1 radioactive water

March 25, 2020

Tokyo Electric Power Company Holdings Inc. said Tuesday it may spend up to 20 to 30 years releasing contaminated water into the surrounding environment from its disaster-crippled Fukushima No. 1 nuclear power plant.

The possible time span was mentioned in draft plans Tepco drew up in line with a government panel’s report in February, calling the release of the water into the ocean or the air in the form of vapor a “realistic option.”

The company currently stores roughly 119 tons of water that still contains tritium and other radioactive substances after passing through a treatment process at the nuclear plant, which suffered a triple meltdown in March 2011 caused by a magnitude 9.0 earthquake and tsunami. The amount of contaminated water stored at the facility is still increasing.

According to the draft plans, Tepco will first conduct secondary treatment work to reduce the amount of radioactive substances in the water other than tritium — which cannot be removed by existing systems — to levels below national standards.

Following the treatment, the water will be released into the ocean, after being diluted with seawater to lower the radiation level to 1,500 becquerels per liter, or emitted into the air from a tall exhaust stack after being vaporized.

Tepco also plans to use social media to counter rumors that exposure to radiation from the released water is harmful.

https://www.japantimes.co.jp/news/2020/03/25/national/tepco-fukushima-nuclear-plant-water/#.Xn3XRHJCeUk

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March 27, 2020 Posted by dunrenard | Fukushima 2020 | Fukushima Daiichi, Radioactive Water, Sea release | Leave a comment

Fukushima: How the ocean became a dumping ground for radioactive waste

The nuclear disaster at Fukushima sent an unprecedented amount of radiation into the Pacific. But, before then, atomic bomb tests and radioactive waste were contaminating the sea — the effects are still being felt today.

March 11, 2020

Almost 1.2 million liters (320,000 gallons) of radioactive water from the Fukushima nuclear power plant is to be released into the ocean. That’s on the recommendation of the government’s advisory panel some nine years after the nuclear disaster on Japan’s east coast. The contaminated water has since been used to cool the destroyed reactor blocks to prevent further nuclear meltdowns. It is currently being stored in large tanks, but those are expected to be full by 2022.

Exactly how the water should be dealt with has become highly controversial in Japan, not least because the nuclear disaster caused extreme contamination off the coast of Fukushima. At the time, radioactive water flowed “directly into the sea, in quantities we have never seen before in the marine world,” Sabine Charmasson from the French Institute for Radiological Protection and Nuclear Safety (IRSN) tells DW.

Radiation levels in the sea off Fukushima were millions of times higher than the government’s limit of 100 becquerels. And still today, radioactive substances can be detected off the coast of Japan and in other parts of the Pacific. They’ve even been measured in very small quantities off the US west coast in concentrations “well below the harmful levels set by the World Health Organization,” according to Vincent Rossi, an oceanographer at France’s Mediterranean Institute of Oceanography (MIO).

The contaminated water in these storage tanks at Fukushima could be released into the sea as of 2022

People observing a minute of silence for the victims of the 2011 earthquake and tsunami

But that doesn’t mean there’s no risk, says Horst Hamm of the Nuclear Free Future Foundation. “A single becquerel that gets into our body is enough to damage a cell that will eventually become a cancer cell,” he says.

A study from the European Parliament reached a similar conclusion. The research found that “even the smallest possible dose, a photon passing through a cell nucleus, carries a cancer risk. Although this risk is extremely small, it is still a risk.”

And that risk is growing. Radioactive pollution in the ocean has been increasing globally — and not just since the disaster at Fukushima.

Atomic bomb tests

In 1946, the US became the first country to test an atomic bomb in a marine area, in the Pacific Bikini Atoll. Over the next few decades, more than 250 further nuclear weapons tests were carried out on the high seas. Most of them (193) were conducted by France in French Polynesia, and by the US (42), primarily in the Marshall Islands and the Central Pacific. 

But the ocean wasn’t just being used as a training ground for nuclear war. Until the early 1990s, it was also a gigantic dump for radioactive waste from nuclear power plants. 

From 1946 to 1993, more than 200,000 tons of waste, some of it highly radioactive, was dumped in the world’s oceans, mainly in metal drums, according to the International Atomic Energy Agency (IAEA). Several nuclear submarines, including nuclear ammunition, were also sunk during this time.

Is the ocean a perfect storage site?

The lion’s share of dumped nuclear waste came from Britain and the Soviet Union, figures from the IAEA show. By 1991, the US had dropped more than 90,000 barrels and at least 190,000 cubic meters of radioactive waste in the North Atlantic and Pacific. Other countries including Belgium, France, Switzerland and the Netherlands also disposed of tons of radioactive waste in the North Atlantic in the 1960s, 70s and 80s.

“Under the motto, ‘out of sight, out of mind,’ the dumping of nuclear waste was the easiest way to get rid of it,” says Horst Hamm.

To this day, around 90% of the radiation in the ocean comes from barrels discarded in the North Atlantic, most of which lie north of Russia or off the coast of Western Europe.

“The barrels are everywhere,” says ecologist Yannick Rousselet of Greenpeace France. He was present in 2000 when the environmental organization used submarines to dive for dumped drums a few hundred meters off the coast of northern France, at a depth of 60 meters (196 feet).

“We were surprised how close they were to the coast,” Rousselet says. “They are rusty and leaking, with the radiation clearly elevated.”

The radioactive pollution of the oceans began in 1946 when the US tested a nuclear bomb at Bikini Atoll Micronesia.

Nuclear waste barrels dumped in the sea decades ago, a common practice in the Channel between France and England in the 1960s, are now rusty and are leaking radioactive substances

Germany also implicated

In 1967, Germany also dumped 480 barrels off the coast of Portugal, according to the IAEA. Responding to a 2012 request for information from the Greens about the condition of those barrels, the German government wrote: “The barrels were not designed to ensure the permanent containment of radionuclides on the sea floor. Therefore, it must be assumed that they are at least partially no longer intact.”

Germany and France don’t want to salvage the barrels. And even Greenpeace activist Yannick Rousselet says he sees “no safe way to lift the rusted barrels” to the surface. That means nuclear waste will likely continue to contaminate the ocean floor for decades to come.

For Horst Hamm, the long-term consequences are clear. The radiation will be “absorbed by the marine animals surrounding it. They will eventually end up caught in fishing nets, and come back to our plates,” he says.

In its 2012 response to the Greens, however, the German government described the risk to humans from contaminated fish as “negligible.”

Rousselet sees things differently: “The entire area along the coast is contaminated by radiation — not just in the sea, in the grass, in the sand, you can measure it everywhere.”

The reprocess in plant in La Hague is still discharging radioactive water into the sea. Cancer rates have increased in the region, according to a report by the European Parliament

Radioactive dumping ground

The main reason behind the radiation along the northern French coastline isn’t the underwater barrels, but rather the nuclear fuel reprocessing plant at La Hague. It is located directly on the coast and “legally discharges 33 million liters of radioactive liquid into the sea each year,” says Rousselet. He thinks it’s scandalous.

In recent years, La Hague has also been the scene of several incidents involving increased radioactivity levels.

The dumping of nuclear waste in drums was banned in 1993 by the London Convention on the Prevention of Marine Pollution. But discharging liquid contaminated with radiation into the ocean is still permitted internationally.

Spike in cancer rates

According to a study by the European Parliament, statistics show cancer rates are significantly higher in the region surrounding La Hague. Cancer rates are also high near the nuclear processing plant in Sellafield in northern England. A study from 2014 concluded that the total amount of radioactivity discharged into the sea from the Sellafield plant over the years is equivalent to the amount released by the nuclear meltdown at Fukushima.

The report say a link to health effects “cannot be ruled out” even if there is no clear evidence to date of a link between illness and radioactive discharges from nuclear facilities.

“The exact effects of radioactive radiation are extremely difficult to measure and prove. We only know that it has an impact,” says Rousselet, adding that it’s crucial to walk away from everything that causes radioactive waste.

Dumping more waste at Fukushima

In Fukushima, the operating company of the Tokyo Electric Power Company nuclear plant claims that before the cooling water is discharged into the sea as planned, all 62 radioactive elements will be filtered down to safe levels — except for the isotope tritium. The advisory panel in Tokyo considers discharging the cooling water into the sea to be “safer” than other alternatives, such as evaporating the water.

Just how harmful tritium is to humans is a source of controversy. According to the plant operator, the concentration of tritium in the collection tanks is sometimes much higher than that of conventional cooling water from nuclear power stations.

“The local fishermen and residents cannot accept the discharge of water,” Takami Morita of the National Research Institute of Fisheries Science said in a press release. While fish pollution levels are below the harmful limit, demand for fish from the region has dropped to one-fifth of what it was before the disaster.

Releasing the cooling water into the sea “is a good method because of the diluting properties of the water,” Sabine Charmasson of the IRSN says. “There aren’t any real problems on the security side, but it’s difficult, because there are also social implications. It might be an appropriate method, but it’s never easy to release radioactive substances into the environment.”

In a press release, Greenpeace said: “There is no justification for additional, deliberate radioactive pollution of the marine environment or atmosphere.”

https://www.dw.com/en/fukushima-how-the-ocean-became-a-dumping-ground-for-radioactive-waste/a-52710277

March 13, 2020 Posted by dunrenard | Fukushima 2020 | Fukushima Daiichi, Radioactive Water, Sea release | 1 Comment

Safety of Fukushima nuke plant waste water focus of sea release debate

In this Feb. 12, 2020 photo, a worker in a hazmat suit carries a hose at a water treatment facility at the Fukushima Daiichi nuclear power plant in Okuma, Fukushima Prefecture.

March 11, 2020

OKUMA, Japan (AP) — Inside a giant decontamination facility at the destroyed Fukushima nuclear power plant, workers in hazmat suits monitor radioactive water pumped from three damaged reactors, making sure it’s adequately — though not completely — treated.

Three lines of equipment connected to pipes snaking around in this dimly lit, sprawling facility can process up to 750 tons of contaminated water a day. Four other lines elsewhere in the plant can process more.

From there, the water is pumped to a complex of about 1,000 temporary storage tanks that crowd the plant’s grounds, where additional tanks are still being built. Officials say the huge tanks will be completely full by the summer of 2022.

The decontamination process, which The Associated Press viewed on a recent tour, is a key element of a contentious debate over what should be done with the nearly 1.2 million tons of still-radioactive water being closely watched by governments and organizations around the world ahead of this summer’s Tokyo Olympics.

The plant’s operator, Tokyo Electric Power Co., or TEPCO, says it needs to free up space as work to decommission the damaged reactors approaches a critical phase. It’s widely expected that TEPCO will gradually release the water into the nearby ocean following a government decision allowing it to do so. The company is still vague on the timing.

But local residents, especially fishermen, are opposed to the plan because they think the water release would hurt the reputation of already battered fisheries, where annual sales remain about half of the level before the nuclear accident, even though the catch has cleared strict radioactivity tests.

TEPCO Chief Decommissioning Officer Akira Ono says the water must be disposed as the plant’s decommissioning moves forward because the area used by the tanks is needed to build facilities for the retrieval of melted reactor debris.

Workers are planning to remove a first batch of melted debris by December 2021. Remote control cranes are dismantling a highly contaminated exhaust tower near Unit 2, the first reactor to get its melted fuel removed. At Unit 3, spent fuel units are being removed from a cooling pool ahead of the removal of melted fuel.

The dilemma over the ever-growing radioactive water is part of the complex aftermath of the magnitude 9.0 earthquake and tsunami that hit on March 11, 2011, destroying key cooling functions at the Fukushima Dai-ichi plant. Three reactors melted, releasing massive amounts of radiation and forcing 160,000 residents to evacuate. About 40,000 still haven’t returned.

Except for the highly radioactive buildings that house the melted reactors, most above-ground areas of the plant can now be visited while wearing just a surgical mask, cotton gloves, a helmet and a personal dosimeter. The area right outside the plant is largely untouched and radiation levels are often higher.

The underground areas remain a hazardous mess. Radioactive cooling water is leaking from the melted reactors and mixes with groundwater, which must be pumped up to keep it from flowing into the sea and elsewhere. Separately, even more dangerously contaminated water sits in underground areas and leaks continuously into groundwater outside the plant, experts say.

The contaminated water pumped from underground first goes through cesium and strontium removal equipment, after which most is recycled as cooling water for the damaged reactors. The rest is filtered by the main treatment system, known as ALPS, which is designed to remove all 62 radioactive contaminants except for tritium, TEPCO says.

Tritium cannot be removed from water and is ‘virtually’ harmless when consumed in small amounts, ‘according’ to Japan’s industry ministry and nuclear regulatory officials.

But despite repeated official reassurances, there are widespread worries about eating fish that might be affected if the contaminated water is released into the sea. Katsumi Shozugawa, a radiology expert at the University of Tokyo who has been analyzing groundwater around the plant, said the long-term consequences of low-dose exposure in the food chain hasn’t been fully investigated.

“At this point, it is difficult to predict a risk,” he said. “Once the water is released into the environment, it will be very difficult to follow up and monitor its movement. So the accuracy of the data before any release is crucial and must be verified.”

After years of discussions about what to do with the contaminated water without destroying the local economy and its reputation, a government panel issued a report earlier this year that narrowed the water disposal options to two: diluting the treated water to levels below the allowable safety limits and then releasing it into the sea in a controlled way, or allowing the water to evaporate in a years-long process.

The report also urged the government to do more to fight the “reputational damage” to Fukushima fishing and farm produce, for instance by promoting food fairs, developing new sales routes and making use of third-party quality accreditation systems.

TEPCO and government officials promise the plant will treat the water for a second time to meet legal requirements before any release.

At the end of the tour of the treatment facility, a plant official showed a glass bottle containing clear water taken from the processing equipment. Workers are required to routinely collect water samples for analysis at laboratories at the plant. Radiology technicians were analyzing the water at one lab, where AP journalists were not allowed to enter. Officials say the treated water will be diluted with fresh water before it is released into the environment.

Doubts about the plant’s water treatment escalated two years ago when TEPCO acknowledged that most of the water stored in the tanks still contains cancer-causing cesium, strontium and other radioactive materials at levels exceeding safety limits.

Masumi Kowata, who lives in Okuma, a town where part of the plant is located, said some of her neighbors are offering their land so that more storage tanks can be built.

“We should not dump the water until we have proof about its safety,” she said. “The government says it’s safe, but how do we know?”

In this Feb. 12, 2020 photo, two workers wearing hazmat suits work at a water treatment facility at the Fukushima Daiichi nuclear power plant in Okuma, Fukushima Prefecture

In this Feb. 12, 2020 photo, a worker removes a plastic layer covering his hazmat suit after working at a water treatment facility at the Fukushima Daiichi nuclear power plant in Okuma, Fukushima Prefecture.

In this Feb. 12, 2020 photo, engineers analyze water samples in a lab at the Fukushima Daiichi nuclear power plant in Okuma, Fukushima Prefecture.

In this Feb. 12, 2020 photo, the No. 1 and 2 reactor buildings, damaged by the 2011 earthquake and tsunami, are seen at the Fukushima Daiichi nuclear power plant in Okuma, Fukushima Prefecture.

https://mainichi.jp/english/articles/20200310/p2g/00m/0fe/094000c

March 13, 2020 Posted by dunrenard | Fukushima 2020 | Fukushima Daiichi, Radioactive Water, Sea release | 1 Comment