Clearing the radioactive rubble heap that was Fukushima Daiichi, 7 years on — Scientific American

” Seven years after one of the largest earthquakes on record unleashed a massive tsunami and triggered a meltdown at Japan’s Fukushima Daiichi nuclear power plant, officials say they are at last getting a handle on the mammoth task of cleaning the site before it is ultimately dismantled. But the process is still expected to be a long, expensive slog, requiring as-yet untried feats of engineering—and not all the details have yet been worked out.

When the disaster knocked out off- and on-site power supplies on March 11, 2011, three of the cooling systems for the plant’s four reactor units were disabled. This caused the nuclear fuel inside to overheat, leading to a meltdown and hydrogen explosions that spewed out radiation. The plant’s operator, Tokyo Electric Power Co. (TEPCO), responded by cooling the reactors with water, which continues today. Meanwhile thousands of people living in the surrounding area were evacuated and Japan’s other nuclear plants were temporarily shut down.

In the years since the disaster and the immediate effort to stanch the release of radioactive material, officials have been working out how to decontaminate the site without unleashing more radiation into the environment. It will take a complex engineering effort to deal with thousands of fuel rods, along with the mangled debris of the reactors and the water used to cool them. Despite setbacks, that effort is now moving forward in earnest, officials say. “We are still conducting studies on the location of the molten fuel, but despite this we have made the judgment that the units are stable,” says Naohiro Masuda, TEPCO’s chief decommissioning officer for Daiichi.

Completely cleaning up and taking apart the plant could take a generation or more, and comes with a hefty price tag. In 2016 the government increased its cost estimate to about $75.7 billion, part of the overall Fukushima disaster price tag of $202.5 billion. The Japan Center for Economic Research, a private think tank, said the cleanup costs could mount to some $470 billion to $660 billion, however.

Under a government roadmap, TEPCO hopes to finish the job in 30 to 40 years. But some experts say even that could be an underestimate. “In general, estimates of work involving decontamination and disposal of nuclear materials are underestimated by decades,” says Rod Ewing, a professor of nuclear security and geological sciences at Stanford University. “I think that we have to expect that the job will extend beyond the estimated time.”

The considerable time and expense are due to the cleanup being a veritable hydra that involves unprecedented engineering. TEPCO and its many contractors will be focusing on several battlefronts.

Water is being deliberately circulated through each reactor every day to cool the fuel within—but the plant lies on a slope, and water from precipitation keeps flowing into the buildings as well. Workers built an elaborate scrubbing system that removes cesium, strontium and dozens of other radioactive particles from the water; some of it is recirculated into the reactors, and some goes into row upon row of giant tanks at the site. There’s about one million tons of water kept in 1,000 tanks and the volume grows by 100 tons a day, down from 400 tons four years ago.

To keep more water from seeping into the ground and being tainted, more than 90 percent of the site has been paved. A series of drains and underground barriers—including a $325-million* supposedly impermeable “wall” of frozen soil—was also constructed to keep water from flowing into the reactors and the ocean. These have not worked as well as expected, though, especially during typhoons when precipitation spikes, so groundwater continues to be contaminated.

Despite the fact contaminated water was dumped into the sea after the disaster, studies by Japanese and foreign labs have shown radioactive cesium in fish caught in the region has fallen and is now within Japan’s food safety limits. TEPCO will not say when it will decide what to do with all the stored water, because dumping it in the ocean again would invite censure at home and abroad—but there are worries that another powerful quake could cause it to slosh out of the tanks.

Fuel Mop-up

A second major issue at Fukushima is how to handle the fuel¾the melted uranium cores as well as spent and unused fuel rods stored at the reactors. Using robotic probes and 3-D imaging with muons (a type of subatomic particle), workers have found pebbly deposits and debris at various areas inside the primary containment vessels in the three of the plant’s reactor units. These highly radioactive remains are thought to be melted fuel as well as supporting structures. TEPCO has not yet worked out how it can remove the remains, but it wants to start the job in 2021. There are few precedents for the task. Lake Barrett—director of the Three Mile Island nuclear plant during its decommissioning after a partial meltdown at the Middletown, Pa., facility in 1979—says TEPCO will use robots to remotely dig out the melted fuel and store it in canisters on-site before shipping to its final disposal spot. “This is similar to what we did at Three Mile Island, just much larger and with much more sophisticated engineering because their damage is greater than ours was,” Barrett says. “So although the work is technically much more challenging than ours was, Japan has excellent technological capabilities, and worldwide robotic technology has advanced tremendously in the last 30-plus years.”

Shaun Burnie, senior nuclear specialist with Greenpeace Germany, doubts the ambitious cleanup effort can be completed in the time cited, and questions whether the radioactivity can be completely contained. Until TEPCO can verify the conditions of the molten fuel, he says, “there can be no confirmation of what impact and damage the material has had” on the various components of the reactors—and therefore how radiation might leak into the environment in the future.

Although the utility managed to safely remove all 1,533 fuel bundles from the plant’s unit No. 4 reactor by December 2014, it still has to do the same for the hundreds of rods stored at the other three units. This involves clearing rubble, installing shields, dismantling the building roofs, and setting up platforms and special rooftop equipment to remove the rods. Last month a 55-ton dome roof was installed on unit No. 3 to facilitate the safe removal of the 533 fuel bundles that remain in a storage pool there. Whereas removal should begin at No. 3 sometime before April 2019, the fuel at units No. 1 and 2 will not be ready for transfer before 2023, according to TEPCO. And just where all the fuel and other radioactive solid debris on the site will be stored or disposed of long-term has yet to be decided; last month the site’s ninth solid waste storage building, with a capacity of about 61,000 cubic meters, went into operation.

As for what the site itself might look like decades from now, cleanup officials refuse to say. But they are quick to differentiate it from the sarcophagus-style containment of the 1986 Chernobyl catastrophe in the Soviet Union, in what is now Ukraine. Whereas the Chernobyl plant is sealed off and the surrounding area remains off-limits except for brief visits—leaving behind several ghost towns—Japanese officials want as many areas as possible around the Daiichi site to eventually be habitable again.

“To accelerate reconstruction and rebuilding of Fukushima as a region, and the lives of locals, the key is to reduce the mid- and long-term risk,” says Satoru Toyomoto, director for international issues at the Ministry of Economy, Trade and Industry’s Nuclear Accident Response Office. “In that regard, keeping debris on the premises without approval is not an option.” ”

by Tim Hornyak, Scientific American

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*The Fukushima nuclear meltdown continues unabated – Helen Caldicott, Global Research News

Dr. Helen Caldicott really tells it how it is. No sugarcoating in this article, just the cold, hard facts.

” Recent reporting of a huge radiation measurement at Unit 2 in the Fukushima Daichi reactor complex does not signify that there is a peak in radiation in the reactor building.

All that it indicates is that, for the first time, the Japanese have been able to measure the intense radiation given off by the molten fuel, as each previous attempt has led to failure because the radiation is so intense the robotic parts were functionally destroyed.

The radiation measurement was 530 sieverts, or 53,000 rems (Roentgen Equivalent for Man). The dose at which half an exposed population would die is 250 to 500 rems, so this is a massive measurement. It is quite likely had the robot been able to penetrate deeper into the inner cavern containing the molten corium, the measurement would have been much greater.

These facts illustrate why it will be almost impossible to “decommission” units 1, 2 and 3 as no human could ever be exposed to such extreme radiation. This fact means that Fukushima Daichi will remain a diabolical blot upon Japan and the world for the rest of time, sitting as it does on active earthquake zones.

What the photos taken by the robot did reveal was that some of the structural supports of Unit 2 have been damaged. It is also true that all four buildings were structurally damaged by the original earthquake some five years ago and by the subsequent hydrogen explosions so, should there be an earthquake greater than seven on the Richter scale, it is very possible that one or more of these structures could collapse, leading to a massive release of radiation as the building fell on the molten core beneath. But units 1, 2 and 3 also contain cooling pools with very radioactive fuel rods — numbering 392 in Unit 1, 615 in Unit 2, and 566 in Unit 3; if an earthquake were to breach a pool, the gamma rays would be so intense that the site would have to be permanently evacuated. The fuel from Unit 4 and its cooling pool has been removed.

But there is more to fear.

The reactor complex was built adjacent to a mountain range and millions of gallons of water emanate from the mountains daily beneath the reactor complex, causing some of the earth below the reactor buildings to partially liquefy. As the water flows beneath the damaged reactors, it immerses the three molten cores and becomes extremely radioactive as it continues its journey into the adjacent Pacific Ocean.

Every day since the accident began, 300 to 400 tons of water has poured into the Pacific where numerous isotopes – including cesium 137, 134, strontium 90, tritium, plutonium, americium and up to 100 more – enter the ocean and bio-concentrate by orders of magnitude at each step of the food chain — algae, crustaceans, little fish, big fish then us.

Fish swim thousands of miles and tuna, salmon and other species found on the American west coast now contain some of these radioactive elements, which are tasteless, odourless and invisible. Entering the human body by ingestion they concentrate in various organs, irradiating adjacent cells for many years. The cancer cycle is initiated by a single mutation in a single regulatory gene in a single cell and the incubation time for cancer is any time from 2 to 90 years. And no cancer defines its origin.

We could be catching radioactive fish in Australia or the fish that are imported could contain radioactive isotopes, but unless they are consistently tested we will never know.

As well as the mountain water reaching the Pacific Ocean, since the accident, TEPCO has daily pumped over 300 tons of sea water into the damaged reactors to keep them cool. It becomes intensely radioactive and is pumped out again and stored in over 1,200 huge storage tanks scattered over the Daichi site. These tanks could not withstand a large earthquake and could rupture releasing their contents into the ocean.

But even if that does not happen, TEPCO is rapidly running out of storage space and is trying to convince the local fishermen that it would be okay to empty the tanks into the sea. The Bremsstrahlung radiation like x-rays given off by these tanks is quite high – measuring 10 milirems – presenting a danger to the workers. There are over 4,000 workers on site each day, many recruited by the Yakuza (the Japanese Mafia) and include men who are homeless, drug addicts and those who are mentally unstable.

There’s another problem. Because the molten cores are continuously generating hydrogen, which is explosive, TEPCO has been pumping nitrogen into the reactors to dilute the hydrogen dangers.

Vast areas of Japan are now contaminated, including some areas of Tokyo, which are so radioactive that roadside soil measuring 7,000 becquerels (bc) per kilo would qualify to be buried in a radioactive waste facility in the U.S..

As previously explained, these radioactive elements concentrate in the food chain. The Fukushima Prefecture has always been a food bowl for Japan and, although much of the rice, vegetables and fruit now grown here is radioactive, there is a big push to sell this food both in the Japanese market and overseas. Taiwan has banned the sale of Japanese food, but Australia and the U.S. have not.

Prime Minister Abe recently passed a law that any reporter who told the truth about the situation could be goaled for ten years. In addition, doctors who tell their patients their disease could be radiation related will not be paid, so there is an immense cover-up in Japan as well as the global media.

The Prefectural Oversite Committee for Fukushima Health is only looking at thyroid cancer among the population and by June 2016, 172 people who were under the age of 18 at the time of the accident have developed, or have suspected, thyroid cancer; the normal incidence in this population is 1 to 2 per million.

However, other cancers and leukemia that are caused by radiation are not being routinely documented, nor are congenital malformations, which were, and are, still rife among the exposed Chernobyl population.

Bottom line, these reactors will never be cleaned up nor decommissioned because such a task is not humanly possible. Hence, they will continue to pour water into the Pacific for the rest of time and threaten Japan and the northern hemisphere with massive releases of radiation should there be another large earthquake. ”

by Helen Caldicott, Global Research News, originally published in Independent Australia

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Increases in perinatal mortality in prefectures contaminated by the Fukushima nuclear power plant accident in Japan — U.S. National Library of Medicine

This is a spatially stratified longitudinal study.

” Abstract

Descriptive observational studies showed upward jumps in secular European perinatal mortality trends after Chernobyl. The question arises whether the Fukushima nuclear power plant accident entailed similar phenomena in Japan. For 47 prefectures representing 15.2 million births from 2001 to 2014, the Japanese government provides monthly statistics on 69,171 cases of perinatal death of the fetus or the newborn after 22 weeks of pregnancy to 7 days after birth. Employing change-point methodology for detecting alterations in longitudinal data, we analyzed time trends in perinatal mortality in the Japanese prefectures stratified by exposure to estimate and test potential increases in perinatal death proportions after Fukushima possibly associated with the earthquake, the tsunami, or the estimated radiation exposure. Areas with moderate to high levels of radiation were compared with less exposed and unaffected areas, as were highly contaminated areas hit versus untroubled by the earthquake and the tsunami. Ten months after the earthquake and tsunami and the subsequent nuclear accident, perinatal mortality in 6 severely contaminated prefectures jumped up from January 2012 onward: jump odds ratio 1.156; 95% confidence interval (1.061, 1.259), P-value 0.0009. There were slight increases in areas with moderate levels of contamination and no increases in the rest of Japan. In severely contaminated areas, the increases of perinatal mortality 10 months after Fukushima were essentially independent of the numbers of dead and missing due to the earthquake and the tsunami. Perinatal mortality in areas contaminated with radioactive substances started to increase 10 months after the nuclear accident relative to the prevailing and stable secular downward trend. These results are consistent with findings in Europe after Chernobyl. Since observational studies as the one presented here may suggest but cannot prove causality because of unknown and uncontrolled factors or confounders, intensified research in various scientific disciplines is urgently needed to better qualify and quantify the association of natural and artificial environmental radiation with detrimental genetic health effects at the population level. ”

by Hagen Heinrich Scherb, Dr rer nat Dipl-Math, Kuniyoshi Mori, MD, and Keiji Hayashi, MD

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Thyroid cancer plagues Fukushima evacuees, but officials deny radiation to blame — Sputnik

” Seven more young Fukushima Prefecture residents have been diagnosed with thyroid cancer, according to a prefectural government statement on Monday. All of the patients were 18 or younger at the time of the 2011 nuclear reactor meltdown.

This bumps the number of Fukushima residents diagnosed with thyroid cancer up to 152. Although many times higher than the national average, the thyroid cancer rates are “unlikely” to have been increased by the reactor accident, according to vice chair of Fukushima’s medical association Hokuto Hoshi.

“Those thyroid cases have been found because we conducted the survey, not because of the radiation,” concurred Akira Ohtsuru, a radiologist who examined many of the patients. “The survey has caused over-diagnosis.”

One of those suspected of having cancer is a 4-year-old boy who hadn’t even been conceived yet when his parents fled Fukushima.

The prefectural government has been conducting thyroid checkups on evacuees every year since 2013.  The number of cases continuously rises every time they do so: five additional cases in 2014 and two additional ones in May 2015. This means more and more evacuees are metastasizing the illness.

Fukushima University researchers have also found that evacuees have markedly higher rates of diabetes, liver and heart disease and obesity than the national average.

A May 2017 study from the Norwegian Institute for Air Research found that the Fukushima nuclear disaster had spread additional radiation across the entire planet, with the same amount of radiation as a single x-ray hitting the average person.

That same month, Penn State Medical Center published a study linking the Three Mile Island nuclear disaster of 1979 to higher rates of thyroid cancer near the Pennsylvania reactor. ”

by Sputnik

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Fukushima moms don lab coats to measure radiation in food, sand and soil — The Japan Times

At a laboratory an hour’s drive from the crippled Fukushima No. 1 nuclear plant, a woman wearing a white mask over her mouth presses bright red strawberries into a pot, ready to be measured for radiation contamination.

Six years after a massive earthquake off the Tohoku coast triggered tsunami that knocked out the plant’s cooling system, causing three reactor-core meltdowns, local mothers with no scientific background staff a laboratory that keeps track of radiation levels in food, water and soil.

As some women divide the samples between different bowls and handmade paper containers, others are logging onto computers to keep an eye on data — findings that will be published for the public to access.

The women on duty, wearing pastel-colored overalls, are paid a small salary to come in for a few hours each day, leaving them free to care for their children after school.

“In universities, data (are) handled by students, who have taken exams qualifying them to measure radiation. Here, it’s done by mothers working part time. It’s a crazy situation,” laughed Kaori Suzuki, director of Tarachine, the nonprofit organization that houses the mothers’ radiation lab.

“If (university professors) saw this I think they would be completely shocked by what they see.”

Tarachine was set up 60 km down the coast from the Fukushima plant, in the city of Iwaki. After the magnitude-9 quake struck on March 11, 2011, triggering mountainous tsunami, authorities declared a no-go zone around the plant.

Iwaki lay outside its 30 km radius, with lower radiation levels compared to the rest of Fukushima Prefecture.

But with public announcements advising locals to stay indoors in the aftermath of the worst nuclear calamity since Chernobyl, the “invisible enemy” of radiation has continued to worry the mothers working at the lab.

“As ordinary citizens we had no knowledge about radiation. All we knew was that it is frightening,” said Suzuki.

“We can’t see, smell or feel radiation levels. Given this invisibility, it was extremely difficult for us. How do we fight it? The only way is to measure it.”

To supplement readings by the central government and Tokyo Electric Power Company Holdings Inc., which manages the nuclear plant, Tarachine publishes its own findings every month.

With donations from the public that helped them buy equipment designed to measure food contamination, the mothers measure radioactive isotopes cesium-134 and-137, and collect data on gamma radiation, strontium-90 and tritium, all of which were released during the Fukushima disaster.

Strontium-90 gravitates toward the bones when absorbed by breathing it, drinking it in water, or eating it in food. It can remain for years, potentially causing bone cancer or leukemia.

Tritium goes directly into the soft tissues and organs of the human body. Although it is less harmful to humans who are exposed to small amounts every day, it could still be a hazard for children, scientists say.

The mothers say other parents trust the lab’s radioactivity readings in local food more than those from the government.

“This issue is part of everyday life for these mothers, so they have the capability to spot certain trends and various problems rather than just accumulating expert knowledge,” said Suzuki.

To handle potentially dangerous materials, the mothers have had to study for exams related to radiation and organic chemistry.

“At the beginning I was just completely clueless. It gave me so much of a headache, it was a completely different world to me,” said Fumiko Funemoto, a mother of two who measures strontium-90 at the lab.

“But you start to get the hang of it as you’re in this environment every day.”

As the lab only accepts items for testing from outside the exclusion zone, most results show comparatively low radiation levels.

But Suzuki said it was an important process and especially reassuring for the parents of young children. The women also measure radiation levels in sand from the beach, which has been out of bounds to their children.

“If the base is zero becquerels, and there is, say, 15 or 16 becquerels of cesium, that’s still higher than zero. That means there is slightly more risk,” Suzuki said.

“There are also times when you’re like, ‘Oh, I thought levels were going to be high there — but it’s actually OK.’ The importance lies in knowing what’s accurate, whether it’s high or low. Unless you know the levels, you can’t implement the appropriate measures.”

Since official screenings began following the meltdowns, 174 children in Fukushima Prefecture have been diagnosed with — or are suspected of having — thyroid cancer, according to figures from the prefecture.

Despite the International Atomic Energy Agency (IAEA) reporting in 2015 that an increase in thyroid cancer is unlikely, the mothers insist there is value in their work.

The first pictures from inside the nuclear plant were released by Tepco in January, announcing it may have found melted nuclear fuel below the damaged reactor 2 — one of three affected by the 2011 disaster.

“In general, the issue of nuclear power is not really talked about much these days,” Funemoto said. “It was talked about after the (meltdowns) for about a year or so, but today, conversations mentioning words like ‘radiation’ don’t happen anymore.”

However, she said “the reality is different.”

“The radiation isn’t going to go away. That’s why I’m doing this. So many places are still damaged. This idea that it’s safe and that we shouldn’t be anxious doesn’t really add up,” she said.

Ai Kimura, another mother, agreed. “My parents think I’m a bit paranoid. They keep saying, ‘It’s OK isn’t it?’ ” she said.

“But what if there’s a chance that in 10 or 20 years’ time, my own child gets thyroid cancer? And I could have done my bit to minimize the risks. My children are mine and I want to do whatever I can to protect them.” ”

by Mari Shibata, The Japan Times

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Mother of bullied Fukushima evacuee reveals details of abuse to court — The Mainichi

” The mother of a student who evacuated from Fukushima Prefecture to Tokyo in the wake of the Fukushima nuclear disaster disclosed to the Tokyo District Court on Jan. 11 that the student had been bullied from elementary school and was told “you’ll probably die from leukemia soon.”

The mother was testifying as part of a damages lawsuit filed against Tokyo Electric Power Co. (TEPCO) and the central government by about 50 plaintiffs including victims who voluntarily relocated to Tokyo after the Fukushima No. 1 Nuclear Power Plant disaster.

“My child was bullied for simply being an evacuee, and not being able to publicly say we are evacuees has caused psychological trauma,” the mother said.

The mother testified that directly after transferring to a public elementary school in Chiyoda Ward following the disaster, her child was bullied by a male classmate who said, “You came from Fukushima so you’ll probably die from leukemia soon.” She said that the teacher, while joking, also added, “You will probably die by the time you’re in middle school.” She also asserted that a classmate pushed her child down the stairs after saying, “You’re going to die anyway, so what’s the difference?”

After moving on to junior high school, the student was reportedly forced by classmates to pay for around 10,000 yen worth of sweets and snacks. This bullying case is currently being investigated by a Chiyoda Ward Board of Education third-party committee. “

by The Mainichi

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