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

source with internal links and photos

Fears of another Fukushima as Tepco plans to restart world’s biggest nuclear plant — The Guardian

” If a single structure can define a community, for the 90,000 residents of Kashiwazaki town and the neighbouring village of Kariwa, it is the sprawling nuclear power plant that has dominated the coastal landscape for more than 40 years.

When all seven of its reactors are in operation, Kashiwazaki-kariwa generates 8.2m kilowatts of electricity – enough to power 16m households. Occupying 4.2 sq km of land along the Japan Sea coast, it is the biggest nuclear power plant in the world.

But today, the reactors at Kashiwazaki-kariwa are idle. The plant in Niigata prefecture, about 140 miles (225km) north-west of the capital, is the nuclear industry’s highest-profile casualty of the nationwide atomic shutdown that followed the March 2011 triple meltdown at Fukushima Daiichi.

The company at the centre of the disaster has encountered anger over its failure to prevent the catastrophe, its treatment of tens of thousands of evacuated residents and its haphazard attempts to clean up its atomic mess.

Now, the same utility, Tokyo Electric Power [Tepco], is attempting to banish its Fukushima demons with a push to restart two reactors at Kashiwazaki-kariwa, one of its three nuclear plants. Only then, it says, can it generate the profits it needs to fund the decommissioning of Fukushima Daiichi and win back the public trust it lost in the wake of the meltdown.

This week, Japan’s nuclear regulation authority gave its formal approval for Tepco to restart the Kashiwazaki-kariwa’s No. 6 and 7 reactors – the same type of boiling-water reactors that suffered meltdowns at Fukushima Daiichi.

After a month of public hearings, the nuclear regulation authority concluded that Tepco was fit to run a nuclear power plant and said the two reactors met the stricter safety standards introduced after the 2011 disaster.

Just before that decision, Tepco gave the Guardian an exclusive tour of what it claims will be the safest nuclear plant in the world.

Now, as on the day of the triple disaster that brought widespread destruction to Japan’s northeast coast, Kashiwazaki-kariwa has the look of a working nuclear plant. Just over 1,000 Tepco staff and 5,000-6,000 contract workers provide the manpower behind a post-Fukushima safety retrofit that is projected to cost 680 billion yen ($6.1bn).

They have built a 15-metre-high seawall that, according to Tepco, can withstand the biggest tsunami waves. In the event of a meltdown, special vents would keep 99.9% of released radioactive particles out of the atmosphere, and corium shields would block molten fuel from breaching the reactors’ primary containment vessels. Autocatalytic recombiners have been installed to prevent a repeat of the hydrogen explosions that rocked four of Fukushima Daiichi’s reactors.

Other parts of the sprawling complex are home to fleets of emergency vehicles, water cannon, back-up power generators, and a hilltop reservoir whose 20,000 tonnes of water will be drawn to cool reactors in the event of a catastrophic meltdown.

“As the operator responsible for the Fukushima accident, we’re committed to learning lessons, revisiting what went wrong and implementing what we learned here at Kashiwazaki-kariwa, says the plant’s chief, Chikashi Shitara. “We are always looking at ways to improve safety.

“Because of our experience at Fukushima, we’re committed to not making the same mistakes again – to make the safety regime even stronger. That’s what we have to explain to members of the public.”

‘This is no place for a nuclear power plant’

The public, however, is far from convinced. Last year, the people of Niigata prefecture registered their opposition to the utility’s plans by electing Ryuichi Yoneyama, an anti-nuclear candidate, as governor. Exit polls showed that 73% of voters opposed restarting the plant, with just 27% in favor.

Yoneyama has said that he won’t make a decision on the restarts, scheduled for spring 2019, until a newly formed committee has completed its report into the causes and consequences of the Fukushima disaster – a process that could take at least three years.

For many residents, the plant’s location renders expensive safety improvements irrelevant. “Geologically speaking, this is no place for a nuclear power plant,” says Kazuyuki Takemoto, a retired local councillor and a lifelong anti-nuclear activist.

Takemoto cites instability caused by the presence of underground oil and gas deposits in the area, and evidence that the ground on which Tepco’s seawall stands is prone to liquefaction in the event of a major earthquake.

Local critics have pointed to the chaos that could result from attempting to evacuate the 420,000 people who live within a 30km radius of Kashiwazaki-kariwa. “That’s more people than lived near Fukushima, plus we get very heavy snowfall here, which would make evacuating everyone impossible,” Takemoto adds. “The situation would be far worse than it was in Fukushima.”

Adding to their concerns are the presence of seismic faults in and around the site, which sustained minor damage during a magnitude-6.6 offshore earthquake in 2007. Two active faults – defined by nuclear regulators as one that has moved any time within the last 400,000 years – run beneath reactor No. 1.

But for Tepco, a return to nuclear power generation is a matter of financial necessity, with the utility standing to gain up to ¥200 billion in annual profits by restarting the two reactors at Kashiwazaki-Kariwa.

The bill for decommissioning Fukushima Daiichi, decontaminating neighbourhoods and compensating residents affected by the meltdown could reach 21.5tr yen [$191bn], according to government estimates. That is on top of the money the firm is spending on importing expensive fossil fuels to fill the vacuum left by the nuclear shutdown.

Earlier this year, the Japan Centre for Economic Research said the total cost of the four-decade Fukushima cleanup – including the disposal of radioactive waste from the plant’s three damaged reactors – could soar to between 50-70tr yen.

“As Tepco’s president and our general business plan have made clear, restarting the reactors here is very important to us as a company,” says Shitara.

Much is at stake, too, for Japan’s prime minister, Shinzo Abe, who has put an ambitious return to nuclear power generation at the centre of his energy policy. His government wants nuclear to provide about 20 percent Japan’s electricity by 2030 – a move that would require the restart of about 30 reactors.

Of the country’s 48 operable reactors, only four are currently online. Several others have passed stringent new safety tests introduced in the wake of Fukushima, but restarts have encountered strong local opposition.

As part of the restart process, people across Japan were recently invited to submit their opinions on the Kashiwazaki-kariwa restart and Tepco’s suitability as a nuclear operator.

Kiyoto Ishikawa, from the plant’s public relations department, insists Tepco has learned the lessons of Fukushima. “Before 3-11 we were arrogant and had stopped improving safety,” he said. “The earthquake was a wake-up call. We now know that improving safety is a continuous process.”

The firm’s assurances were dismissed by Yukiko Kondo, a Kariwa resident, who said the loss of state subsidies if the plant were to remain permanently idle was a sacrifice worth making if it meant giving local people peace of mind.

“Tepco caused the 2011 accident, so there is no way I would ever support restarting nuclear reactors here,” she said. “They kept telling us that Fukushima Daiichi was perfectly safe – and look what happened.” ”

by Justin McCurry, The Guardian

source with internal links

Near miss at Fukushima is a warning for U.S., panel says — Richard Stone, Science

” Japan’s chief cabinet secretary called it “the devil’s scenario.” Two weeks after the 11 March 2011 earthquake and tsunami devastated the Fukushima Daiichi Nuclear Power Plant, causing three nuclear reactors to melt down and release radioactive plumes, officials were bracing for even worse. They feared that spent fuel stored in the reactor halls would catch fire and send radioactive smoke across a much wider swath of eastern Japan, including Tokyo.

Thanks to a lucky break detailed in a report released today by the U.S. National Academies, Japan dodged that bullet. The near calamity “should serve as a wake-up call for the industry,” says Joseph Shepherd, a mechanical engineer at the California Institute of Technology in Pasadena who chaired the academy committee that produced the report. Spent fuel accumulating at U.S. nuclear reactor plants is also vulnerable, the report warns. A major spent fuel fire at a U.S. nuclear plant “could dwarf the horrific consequences of the Fukushima accident,” says Edwin Lyman, a physicist at the Union of Concerned Scientists, a nonprofit in Washington, D.C., who was not on the panel.

After spent fuel is removed from a reactor core, the fission products continue to decay radioactively, generating heat. Many nuclear plants, like Fukushima, store the fuel onsite at the bottom of deep pools for at least 5 years while it slowly cools. It is seriously vulnerable there, as the Fukushima accident demonstrated, and so the academy panel recommends that the U.S. Nuclear Regulatory Commission (NRC) and nuclear plant operators beef up systems for monitoring the pools and topping up water levels in case a facility is damaged. It also calls for more robust security measures after a disaster. “Disruptions create opportunities for malevolent acts,” Shepherd says.

At Fukushima, the earthquake and tsunami cut power to pumps that circulated coolant through the reactor cores and cooled water in the spent fuel pools. The pump failure led to the core meltdowns. In the pools, found in all six of Fukushima’s reactor halls, radioactive decay gradually heated the water. Of preeminent concern were the pools in reactor Units 1 through 4: Those buildings had sustained heavy damage on 11 March and in subsequent days, when explosions occurred in Units 1, 3, and 4.

The “devil’s scenario” nearly played out in Unit 4, where the reactor was shut down for maintenance. The entire reactor core—all 548 assemblies—was in the spent fuel pool, and was hotter than fuel in the other pools. When an explosion blew off Unit 4’s roof on 15 March, plant operators assumed the cause was hydrogen—and they feared it had come from fuel in the pool that had been exposed to air. They could not confirm that, because the blast had destroyed instrumentation for monitoring the pool. (Tokyo Electric Power Company, the plant operator, later suggested that the hydrogen that had exploded had come not from exposed spent fuel but from the melted reactor core in the adjacent Unit 3.) But the possibility that the fuel had been exposed was plausible and alarming enough for then-NRC Chairman Gregory Jaczko on 16 March to urge more extensive evacuations than the Japanese government had advised—beyond a 20-kilometer radius from the plant.

Later that day, however, concerns abated after a helicopter overflight captured video of sunlight glinting off water in the spent fuel pool. In fact, the crisis was worsening: The pool’s water was boiling away because of the hot fuel. As the level fell perilously close to the top of the fuel assemblies, something “fortuitous” happened, Shepherd says. As part of routine maintenance, workers had flooded Unit 4’s reactor well, where the core normally sits. Separating the well and the spent fuel pool is a gate through which fuel assemblies are transferred. The gate allowed water from the reactor well to leak into the spent fuel pool, partially refilling it. Without that leakage, the academy panel’s own modeling predicted that the tops of the fuel assemblies would have been exposed by early April; as the water continued to evaporate, the odds of the assemblies’ zirconium cladding catching fire would have skyrocketed. Only good fortune and makeshift measures to pump or spray water into all the spent fuel pools averted that disaster, the academy panel notes.

At U.S. nuclear plants, spent fuel is equally vulnerable. It is for the most part densely packed in pools, heightening the fire risk if cooling systems were to fail. NRC has estimated that a major fire in a U.S. spent fuel pool would displace, on average, 3.4 million people from an area larger than New Jersey. “We’re talking about trillion-dollar consequences,” says panelist Frank von Hippel, a nuclear security expert at Princeton University.

Besides developing better systems for monitoring the pools, the panel recommends that NRC take another look at the benefits of moving spent fuel to other storage as quickly as possible. Spent fuel can be shifted to concrete containers called dry casks as soon as it cools sufficiently, and the academy panel recommends that NRC “assess the risks and potential benefits of expedited transfer.” A wholesale transfer to dry casks at U.S. plants would cost roughly $4 billion. ”

by Richard Stone, Science

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**Writing the nuclear meltdown playbook — Arnie Gundersen via Fairewinds Energy Education

Arnie Gundersen: ” People today who are familiar with social media think that TMI means “Too Much Information”. But to me, and anyone listening to the news in 1979, TMI will always represent the disaster at Three Mile Island, when the public received too little information, not too much.

At the time of the nuclear disaster at TMI, there were plans to build more than 200 nuclear plants in the US, with some projections topping 1,000. Today, less than 100 nuclear plants are operating in the US. During the 1970’s, the total amount invested in those early plants easily exceeded one trillion dollars. If the public became fearful of nuclear power, then the nuclear industry, investors, and banks that had loaned money would face huge losses, so the nuclear industry and nuclear regulators tried desperately to minimize the significance of what was happening at the crippled reactor.

The pattern of denial created by the nuclear industry during the TMI meltdown had at least five steps in its playbook:

  1. Make it appear that “authorities” have the situation under control.
  2. Delay any evacuation orders for as long as possible.
  3. Claim radiation releases are much lower than they actually are.
  4. Claim radiation exposures are acceptable and that no one will die.
  5. And lastly, minimize conflicting information given to the press through paid off experts.

The formula for damage control at TMI was designed by the nuclear industry composed a one size fits all “playbook” the industry has followed for all nuclear catastrophes since TMI. Comments made during the triple meltdown at Fukushima Daiichi by utility owner Tokyo Electric could easily mimic those made at Chernobyl and TMI! When Maggie and I saw these old tricks being played again at Fukushima Daiichi, we dedicated ourselves to ensuring that the public has an accessible resource on which to rely that provides accurate information, and thus the Fairewinds videos were born.

In this video posted to commemorate the TMI disaster, I discuss the pattern of denial regarding nuclear power plant failures and meltdowns, not just for TMI but also for Chernobyl and Fukushima Daiichi as well. We at Fairewinds Energy Education hope you will watch it and think about sharing the true facts with others. ”

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Arnie Gundersen speaks at THE WAVE conference

Arnie Gundersen, founder of Fairewinds Energy Education and former nuclear engineer, spoke at The WAVE conference sponsored by Life Chiropractic College West near San Francisco, Calif., about the risks of nuclear energy, particularly those at Fukushima Daiichi. His four main presentation points are these: “(1) Nuclear accidents happen frequently; (2) As time goes on, accidents have become increasingly more severe; (3) As bad as it continues to be, Fukushima could have been much worse; and (4) Radiation knows no borders.”

Watch Gundersen’s presentation HERE.