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At stake is Tepco's reputation, the health and livelihoods of local communities, and the future direction of the industry worldwide.
Nature wrote:Killer qualities of Japanese fault revealed
Ocean drilling finds thin, weak layer of clay was behind giant earthquake and tsunami of 2011.
The devastating 2011 earthquake and tsunami in Japan shocked researchers who did not expect that the seismic fault involved could release so much energy. Now the world's deepest-drilling oceanographic ship has been able to pin down the odd geology that made this disaster so horrific.
The fault turns out to be unusually thin and weak, the researchers report in Science this week1–3. The results will help to pin down whether other offshore faults around the world are capable of triggering the same scale of disaster.
(...)
The magnitude-9 Tohoku-Oki earthquake of 11 March 2011 was really two quakes in one: a conventional, deeper quake near the epicentre that caused the ground to shake; and an odd, shallow quake further out to sea that caused an astonishing, record-breaking 50 metres of sideways land slip. It was this displacement of the sea floor that kicked up a massive tsunami. In the textbook version of so-called ‘subduction zones’, where an oceanic plate dives under another tectonic plate, as it does in this area, the shallow portions near the sea floor should be resistant to slipping: as the soft sediments move, friction is meant to build up and stop further sliding. But in this case, the slip was severe.
...more...
Japan is incapable of safely decommissioning the devastated Fukushima nuclear plant alone and must stitch together an international team for the massive undertaking, experts say, but has made only halting progress in that direction.
Unlike the U.S. and some European countries, Japan has never decommissioned a full-fledged reactor. Now it must do so at the Fukushima Dai-Ichi plant. Three of its six reactors melted down after the 2011 earthquake and tsunami, making what is ordinarily a technically challenging operation even more complex.
The cloud over Japan's capacity to get the decades-long job done has further undermined the image of the nuclear industry with the public. Opinion surveys show a majority of Japanese are opposed to restarting 50 reactors that were put offline for safety and other checks in the aftermath of the disaster. Japan has been forced to import oil and gas to meet its power needs, burdening its already feeble economy.
"Even for the U.S. nuclear industry, such a cleanup and decommissioning would be a great challenge," said Akira Tokuhiro, a University of Idaho professor of mechanical and nuclear engineering who is among those calling for a larger international role at Fukushima.
Decommissioning a nuclear power plant normally involves first bringing the reactor cores to stable shutdown, and then eventually removing them for long-term storage. It is a process that takes years. Throughout, radiation levels and worker exposure must be monitored.
At Fukushima, there is the daunting challenge of taking out cores that suffered meltdown, which is the most dangerous type of nuclear power accident. Their exact location within the reactor units isn't known and needs to be ascertained so their condition can be analyzed. That will require development of nimble robots capable of withstanding high radiation.
The lack of experts is worse at the regulatory level. The tally is zero.
Japan's Nuclear Regulation Authority has no one devoted to decommissioning, said spokesman Juntaro Yamada, though it has experts dealing with the ongoing removal of fuel rods from one of the Fukushima reactor units.
Its predecessor organization was criticized after the Fukushima disaster for being too close to the nuclear industry, so the members chosen for the new agency launched last year don't have direct ties to the industry to ensure their objectivity.
The government-funded Nuclear Energy Safety Organization, which is to be folded into the regulatory authority to beef up its expertise, has one expert on decommissioning, a person who studies overseas regulations on the process. The group mainly helps with routine nuclear plant inspections, but since the 2011 catastrophe has been involved with bringing the Fukushima plant under control.
In contrast, the U.S. Nuclear Regulatory Commission has 10 people devoted to decommissioning including four project managers, four health physicists, and a hydro-geologist. It says it has the equivalent of more than 200 years of experience in decommissioning and has overseen the termination of 11 power reactors and 13 research reactors.
France has decommissioned nine reactors, and its regulatory agency has seven decommissioning experts at the national level, and 10 more at the local level.
Lake Barrett, a retired nuclear engineer who took part in decommissioning Pennsylvania's Three Mile Island after the meltdown of its reactor core in 1979, was hired as a consultant by Fukushima operator Tokyo Electric Power Co. He visits about once a year or so to give advice, and is not assigned daily to the job...
Navy sailor Lindsay Cooper knew something was wrong when billows of metallic-tasting snow began drifting over USS Ronald Reagan.
“I was standing on the flight deck, and we felt this warm gust of air, and, suddenly, it was snowing,” Cooper recalled of the day in March 2011 when she and scores of crewmates watched a sudden storm blow toward them from the tsunami-torn coast of Fukushima, Japan.
The tall 24-year-old with a winning smile didn’t know it then, but the snow was caused by the freezing Pacific air mixing with a plume of radioactive steam from the city’s shattered nuclear reactor.
Now, nearly three years after their deployment on a humanitarian mission to Japan’s ravaged coast, Cooper and scores of her fellow crew members on the aircraft carrier and a half-dozen other support ships are battling cancers, thyroid disease, uterine bleeding and other ailments.
“We joked about it: ‘Hey, it’s radioactive snow!’ ” Cooper recalled. “I took pictures and video.”
But now “my thyroid is so out of whack that I can lose 60 to 70 pounds in one month and then gain it back the next,” said Cooper, fighting tears. “My menstrual cycle lasts for six months at a time, and I cannot get pregnant. It’s ruined me.”
The fallout of those four days spent off the Fukushima coast has been tragic to many of the 5,000 sailors who were there.
At least 70 have been stricken with some form of radiation sickness, and of those, “at least half . . . are suffering from some form of cancer,” their lawyer, Paul Garner, told The Post Saturday.
“We’re seeing leukemia, testicular cancer and unremitting gynecological bleeding requiring transfusions and other intervention,” said Garner, who is representing 51 crew members suing the Tokyo Electric Power Co., which operates the Fukushima Daiichi energy plant.
“Then you have thyroid polyps, other thyroid diseases,” added Garner, who plans to file an amended lawsuit in federal court in San Diego next month that will bring the number of plaintiffs past 70.
Senior Chief Michael Sebourn, a radiation-decontamination officer, was assigned to test the aircraft carrier for radiation.
The levels were incredibly dangerous and at one point, the radiation in the air measured 300 times higher than what was considered safe, Sebourn told The Post.
The former personal trainer has suffered a series of ailments, starting with severe nosebleeds and headaches and continuing with debilitating weakness.
He says he has lost 60 percent of the power in the right side of his body and his limbs have visibly shrunk.
“I’ve had four MRIs, and I’ve been to 20 doctors,” he said. “No one can figure out what is wrong.”
He has since retired from the Navy after 17 years of service.
Even as the Reagan was steaming toward the disaster, power-company officials knew the cloud of steam they were releasing — in order to relieve pressure in the crippled plant — was toxic, the lawsuit argues, a claim that has also been made by the Japanese government.
Tokyo Electric Power also knew that radioactivity was leaking at a rate of 400 tons a day into the North Pacific, according to the lawsuit and Japanese officials.
“We were probably floating in contaminated water without knowing it for a day and a half before we got hit by that plume,” said Cooper, whose career as a third-class petty officer ended five months after the disaster for health reasons.
The toxic seawater was sucked into the ship’s desalinization system, flowing out of its faucets and showers — still radioactive — and into the crew member’s bodies.
All I drink is water. You stay hydrated on that boat,” said Cooper, who worked up to 18 hours at a time on the flight deck loading supplies onto a steady stream of aid helicopters for four days, all the while drinking out of the two-gallon pouch of water hooked to her gear belt.
By the time the Reagan realized it was contaminated and tried to shift location, the radioactive plume had spread too far to be quickly outrun.
“We have a multimillion-dollar radiation-detection system, but . . . it takes time to be set up and activated,” Cooper said.
“And then we couldn’t go anywhere. Japan didn’t want us in port, Korea didn’t want us, Guam turned us away. We floated in the water for two and a half months,” until Thailand took them in, she said.
All the while crew members had been suffering from excruciating diarrhea.
“People were s- -tting themselves in the hallways,” Cooper recalled.
“Two weeks after that, my lymph nodes in my neck were swollen. By July, my thyroid shut down.”
Cooper, the single mother of a 4-year-old girl named Serenity, says her biggest worry is that she will get cancer. Her own mother died recently of breast cancer at age 53.
“This isn’t about financial gain,” Cooper said of the lawsuit. “This is about what’s going to happen while I’m sick, and then after I’m gone.”
“I worry,” she added, her voice choking, “because I have a daughter. And I’m so sick.”
Link
Tokaimura Criticality Accident 1999
updated October 2013
In 1999 three workers received high doses of radiation in a small Japanese plant preparing fuel for an experimental reactor.
The accident was caused by bringing together too much uranium enriched to a relatively high level, causing a "criticality" (a limited uncontrolled nuclear chain reaction), which continued intermittently for 20 hours.
A total of 119 people received a radiation dose over 1 mSv from the accident, but only the three operators' doses were above permissible limits. Two of the doses proved fatal.
The cause of the accident was "human error and serious breaches of safety principles", according to IAEA.
Safety in the nuclear fuel cycle has always been focused on reactor operations, where a huge amount of energy is released continuously in a small volume of material, and where there are substantial amounts of radioactive materials which would be very hazardous if released to the biosphere. A secondary focus is then the high-level wastes from the reactor, which comprise all the potentially hazardous materials from the reactor core.
Other parts of the nuclear fuel cycle have much less potential for widespread harm to people or the environment. They are correspondingly less regulated in some countries, such as Japan.
The Tokaimura plant
The 1999 Tokai-mura accident was in a very small fuel preparation plant operated by Japan Nuclear Fuel Conversion Co. (JCO), a subsidiary of Sumitomo Metal Mining Co. It was not part of the electricity production fuel cycle, nor was it a routine manufacturing operation where operators might be assumed to know their jobs reasonably well.
The particular JCO plant at Tokai was commissioned in 1988 and processed up to 3 tonnes per year of uranium enriched up to 20% U-235, a much higher than for ordinary power reactors. The plant supplied various specialised research and experimental reactors. It uses a wet process.
The approved nuclear fuel preparation procedure involved dissolving uranium oxide (U3O8) powder in nitric acid in a dissolution tank, then its transfer as pure uranyl nitrate solution to a storage column for mixing, followed by transfer to a precipitation tank. This tank is surrounded by a water cooling jacket to remove excess heat generated by the exothermic chemical reaction. The prevention of criticality was based upon the general licensing requirements for mass and volume limitation, as well as upon the design of the process. A key part of the design was the storage column with a criticality-safe geometry and allowing careful control of the amount of material transferred to the precipitation tank.
However, the company's work procedure was modified three years earlier, without permission from the regulatory authorities, to allow uranium oxide to be dissolved in stainless steel buckets rather than the dissolution tank. It was then modified further by the operators to speed things up by tipping the solution directly into the precipitation tank. The mixing designed to occur in the storage column was instead undertaken by mechanical stirring in the precipitation tank, thus bypassing the criticality controls. Also there was no proper control of the amount tipped into the hundred-litre precipitation tank, and its shape (450 mm diameter and 660 mm high) enhanced the likelihood of criticality within it.
The accident
On 30 September three workers were preparing a small batch of fuel for the JOYO experimental fast breeder reactor, using uranium enriched to 18.8% U-235. It was JCO's first batch of fuel for that reactor in three years, and no proper qualification and training requirements had been established to prepare those workers for the job. They had previously used this procedure many times with much lower-enriched uranium - less than 5%, and had no understanding of the criticality implications of 18.8% enrichment. At around 10:35, when the volume of solution in the precipitation tank reached about 40 litres, containing about 16 kg U, a critical mass was reached.
At the point of criticality, the nuclear fission chain reaction became self-sustaining and began to emit intense gamma and neutron radiation, triggering alarms. There was no explosion, though fission products were progressively released inside the building. The significance of it being a wet process was that the water in the solution provided neutron moderation, expediting the reaction. (Most fuel preparation plants use dry processes.)
The criticality continued intermittently for about 20 hours. It appears that as the solution boiled vigorously, voids formed and criticality ceased, but as it cooled and voids disappeared, the reaction resumed. The reaction was stopped when cooling water surrounding the precipitation tank was drained away, since this water provided a neutron reflector. Boric acid solution (neutron absorber) was finally was added to the tank to ensure that the contents remained subcritical. These operations exposed 27 workers to some radioactivity. The next task was to install shielding to protect people outside the building from gamma radiation from the fission products in the tank. Neutron radiation had ceased.
The radiation (neutron and gamma) emanated almost entirely from the tank, not from any dispersed materials. Buildings housing nuclear processing facilities such as this are normally maintained at a lower pressure than atmosphere so that air leakage is inward, and any contamination is removed by air filters connected to an exhaust stack. In this case particulate radionuclides generated within the conversion building were collected by the high-efficiency particulate air filters, though noble gases passed through the filters. A smoke test on 5 October confirmed that the negative pressure had been maintained (ie the structural integrity of the building was satisfactory) and that the ventilation system was working. However, owing to the detection of low levels of iodine-131 being released to the environment through the exhaust, it was later decided to stop ventilation and to rely on the passive confinement provided by the building.
Five hours after the start of the criticality, evacuation commenced of some 161 people from 39 households within a 350 metre radius from the conversion building. They were allowed home two days later after sandbags and other shielding ensured no hazard from residual gamma radiation. Twelve hours after the start of the incident residents within 10 km were asked to stay indoors as a precautionary measure, and this restriction was lifted the following afternoon.
chokonen888 wrote:...any coincidence this is just making headlines now? (after that state secret shit passed)
Doctor Stop wrote:chokonen888 wrote:...any coincidence this is just making headlines now? (after that state secret shit passed)
Nah, their lawsuit was news a few months ago. It's a bullshit lawsuit with a bunch of errors in it. Look around and you might find a copy of the suit.
yanpa wrote:Put it this way, before Fukushima I only had two legs.
Russell wrote:In my case, before Fukushima I couldn't play the violin.
(...)
And neither can I now...
yanpa wrote:Russell wrote:In my case, before Fukushima I couldn't play the violin.
(...)
And neither can I now...
So you're saying Fukushima robbed you of the chance of becoming a violin virtuoso?
In March of 2011, an undersea earthquake sent tsunamis thundering across Japan, killing nearly 20,000 people and creating the most expensive natural disaster in history. Among the casualities was the Fukushima Daiichi Nuclear Power Plant, which was almost completely submerged by the tsunamis; an unprecedented event. Power was lost (obviously), cooling systems stopped, and the net result was a complete meltdown of three of the plant's reactor cores. It was a perfect storm of worst case scenarios. And now, even years afterward, some are calling it a worldwide radiation disaster, worse than even Chernobyl, that will produce a staggering death count for decades or even centuries. Today we're going to evaluate these assertions and see if we can separate fact from fiction...
■January 15■ Max Demand Forecast: 45.10GW (5:00 pm-6:00 pm), Max Supply Capacity: 51.95GW.
http://t.co/3KwP4Q3Jrr
--- TEPCO (@TEPCO_English)'s twitter January 15, 2014
Mike Oxlong wrote:Fukushima vs Chernobyl vs Three Mile IslandIn March of 2011, an undersea earthquake sent tsunamis thundering across Japan, killing nearly 20,000 people and creating the most expensive natural disaster in history. Among the casualities was the Fukushima Daiichi Nuclear Power Plant, which was almost completely submerged by the tsunamis; an unprecedented event. Power was lost (obviously), cooling systems stopped, and the net result was a complete meltdown of three of the plant's reactor cores. It was a perfect storm of worst case scenarios. And now, even years afterward, some are calling it a worldwide radiation disaster, worse than even Chernobyl, that will produce a staggering death count for decades or even centuries. Today we're going to evaluate these assertions and see if we can separate fact from fiction...
In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction involving uranium-235.
wagyl wrote:OMG is this for real?
Isle of View wrote:wagyl wrote:OMG is this for real?
Yeah, that accent is unbelievable. Does anyone actually talk like that?
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