More Damage Than Expected at Fukushima By AP / MARI YAMAGUCHI Thursday, May 12, 2011
(TOKYO) — One of the reactors at Japan's crippled nuclear power plant has been damaged more severely than originally thought, officials said Thursday — a serious setback for efforts to stabilize the radiation-leaking complex.
Repairs to monitoring equipment revealed the new data, which also showed that the water level in the core of Unit 1 at the Fukushima Dai-ichi plant is much lower than previously thought, leaving the portion of the fuel rods still intact fully exposed. Other fuel has slumped to the bottom of the pressure vessel and is thought to be covered in water. (See inside the Fukushima exclusion zone.)
The findings also indicate a greater-than-expected leak in that vessel. Radioactive water pouring from troubled reactors has pooled around the complex, hindering work to bring the plant under control.
However, temperatures in the unit are still far below dangerous levels because the plant's operator, Tokyo Electric Power Co., continues to inject new water to keep the rods cool. That radioactive water is apparently then leaking into and through the larger, beaker-shaped drywell, or containment vessel.
"The situation (in the core) hasn't changed since (early in the crisis), and the fuel rods are being cooled by water continuously being injected into the core," nuclear official Takashi Sakurai said.
Nuclear Industrial and Safety Agency officials said the new data indicates that it is likely that partially melted fuel had fallen to the bottom of the pressurized vessel that holds the reactor core together and possibly leached down into the drywell soon after the March 11 quake and tsunami that struck Japan's northeastern coast.
While officials said it was unlikely that the chunks of fuel were still dangerously hot or that they could melt through the concrete base of containment vessel, they acknowledged that the level of damage could complicate plans detailed in April to bring the plant to a cold shutdown within nine months. Further examination was needed to ascertain the full extent of damage, they said.
TEPCO had adopted an unorthodox method of trying to cool Unit 1's reactor by trying to fill the drywell with water leaking from the core, but the possibility that chunks of melted fuel had fallen and damaged part the containment vessel raised questions about how successful this method would be. It also called into question the utility's timeline for stabilizing the reactor.
"We have to revise the flooding method, as we need to re-examine the way we carry it out," Matsumoto said. (See what Japan's energy future looks like.)
Recent temperatures inside Unit 1's core were at the most 237 degrees Fahrenheit (114 Celsius), well below the normal operating temperature of about 570 Fahrenheit (300 Celsius). Zirconium fuel rod casing begin to break down at 2,200 Fahrenheit (1,200 Celsius) and melt at 3,900 Fahrenheit (2,200 Celsius).
The new findings became available as workers fixed a water meter Tuesday after entering the building for the first time since a March 12 hydrogen explosion at the unit.
The gauge showed that the water was at least three feet (one meter) below the 13-foot-long (four-meter-long) fuel rods, which are suspended in the pressure vessel. Some of the rods has melted away, however, and the chunks of damaged fuel are presumed to be sitting at the bottom of the vessel, covered in water.
The low level of water indicates that the core of Unit 1 had a bigger breach than expected, said TEPCO spokesman Junichi Matsumoto.
Cooling water has been leaking from the reactor cores of Units 2 and 3 as well, allowing an estimated 70,000 tons of contaminated water to pool inside the complex, which TEPCO has been struggling to bring under control for two months.
To prevent contaminated water from leaking into the ocean, workers in April began pumping it into a waste processing building while a system to decontaminate the water is set up.
The plant, 140 miles (220 kilometers) north of Tokyo, has a total of six reactors. Units 5 and 6 have already reached cold shutdown. Unit 4 contained no fuel rods at the time of the earthquake, but workers have needed to spray water into its spent fuel pool where still-hot rods are stored and structural damage and leakage are suspected.
The government on Thursday also delayed the announcement of a plan to ensure that TEPCO fulfills its obligation to compensate tens of thousands of people affected by the crisis. Prime Minister Naoto Kan said further discussion was needed.
Under the plan, a new fund would be created with mandatory contributions from electric utilities, including TEPCO, in case TEPCO's total compensation exceeds its financial capacity. The government could also add public money if needed.
TEPCO would be required to repay any money it uses from the fund. The utility has agreed to drastic restructuring, cost-cutting and other conditions in exchange for government support in the compensation scheme. http://www.time.com/time/wo...8599,2071255,00.html
[This message has been edited by dennis_6 (edited 05-13-2011).]
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11:24 AM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
IITATE, Fukushima Pref. — Sleepy, idyllic and dangerously irradiated, the village of Iitate is preparing to evacuate.
News photo Stony silence: Residents who were forced to evacuate from their homes in Iitate, Fukushima Prefecture, listen to Norio Tsuzumi, executive vice president of Tokyo Electric Power Co., speak about the crippled Fukushima No. 1 nuclear plant April 30. KYODO PHOTO
The junior high school is closed, its children bused every day to nearby towns. Tractors sit idle, and weeds poke through rice and cabbage in the fields. Half-empty shelves greet customers at the A-Coop supermarket.
By the end of the month, this mountainous farming village of 7,000 people in Fukushima Prefecture, recently voted one of Japan's most beautiful places, will join the Ukrainian ghost town of Pripyat on the planet's short list of nuclear casualties.
"We've no idea when we can come back," said Katsuzo Shoji, who farms rice and cabbage, and keeps a small herd of cattle about 2 km from Iitate's village office.
Shoji, 75, went from shock to rage and then despair when the government told him he would have to destroy his vegetables, kill his six cows and move with his wife, Fumi, 73, to an apartment, probably in the city of Koriyama about 20 km away.
"We've heard five, maybe 10 years, but some say that's far too optimistic," he said, crying. "Maybe I'll be able to come home to die."
Iitate has been living on borrowed time since the March 11 quake and tsunami knocked out the cooling systems of the Fukushima No. 1 nuclear power plant, about 40 km away. Though outside the government's 30-km danger zone set up around the plant, the village's mountainous topography meant radiation spewing from its crippled reactors lingered, poisoning crops and water.
The young, the wealthy, mothers and pregnant women began leaving for Tokyo or elsewhere. The rest gathered every day in the village office for information and prayed against the inevitable.
Last month, the central government finally ordered the remaining citizens to leave after the International Atomic Energy Agency and other observers warned that safe radiation limits for cesium and other toxins had been exceeded.
"We've been told to quit our jobs and move out by the end of the month," said Miyoko Nakamura, 59, a clerk in the village office. She is near retirement and says she'll manage. "A lot of people have no idea what to do. They're just hoping everything will be OK somehow."
Villagers snort at the initial compensation of ¥1 million offered by Tokyo Electric Power Co., operator of the ruined Fukushima plant. Farmers will be given another ¥350,000 in moving expenses this month. After that, there are no more concrete promises.
"Money is the biggest question people have," explained Takashi Hamasaka, an official from the Ministry of Economy, Trade and Industry seconded to the village to assist with the evacuation. "They want the government to pay more.
"If it was just a tsunami or earthquake we would pay, but the nuclear problem was made by Tepco so the situation is so difficult," he said.
Among the government's tasks is finding homes for 700 family pets that will be left behind. Thousands of pigs and more than 8,000 of the region's famous, prized "wagyu" beef cattle, worth up to ¥1 million a head, will be slaughtered if they can't be relocated.
Apartments in towns outside the irradiated zone must be found for the people, who are being kept alive on supplies shipped into the village office. Bottled water, masks and diapers for bedridden elderly lie in boxes around the hall. Locals arrive in light vans to pick up the supplies and glance at the Geiger counter across the road, which hovers at around 3.15 microsieverts per hour.
Tepco officials, led by Executive Vice President Norio Tsuzumi, came to the village hall more than a week ago to apologize.
Pictures from the visit show the officials, dressed in identical utility suits, bowing deeply before 1,000 mostly stony-faced locals.
"Give us back our beautiful village," one demanded.
Some say the disaster is too big for any company to manage, even one as powerful as Japan's largest utility.
"At least they can raise electricity prices," said Shoji. "What can we do except wait for our homes back?"
Local restaurants have already shut. Many display signs of a smiling cartoon cow, the symbol of Iitate beef. Now the beef is too irradiated to sell.
The lone supermarket, a crucial lifeline to many elderly customers, still operates — at least for now. A notice on the window lists the names of nonprofit organizations willing to look after abandoned pets.
"We're waiting to see what happens; some older people are not leaving and they need us," said manager Toshiyuki Matsuda. "They would have to shop 20 km away if we weren't here."
A woman in the parking lot outside was bundling her shopping into a small pickup truck.
"I'm old, I've been here all my life — where would I go?" she asked. "I'm going to stay and if the supermarket closes I'll go elsewhere."
METI official Hamasaka shrugged his shoulders when asked what the government would do about holdouts.
"It's a good question. We don't have any power to force them to go."
Faced with a similar problem closer to the stricken nuclear plant, the government last month turned the 20-km zone around it into a no-go area. Evacuees who return there now face arrest and fines. Hundreds of thousands of farm animals are being slaughtered.
Farmers in the vicinity claim their produce is safe to eat, but that the country has become hysterical about Fukushima's fallout. Many have heard stories of children evacuated from the village, sometimes hundreds of kilometers away, being bullied, a painful echo of the decades-long discrimination that dogged survivors of the atomic bombings of Hiroshima and Nagasaki.
"I've heard that other kids shout 'baikin' (vermin) at them," said Shoji's granddaughter, Hiroko, 22.
Like many in the area, Shoji, whose family has been farming this land since the 1880s, is too old to become embroiled in a protracted legal battle with Tepco or the government.
"All we can do is bow our heads and heed the order," he said as his wife, granddaughter and eldest son, Hidekatsu, looked sadly on. He has been told that he will be taken care of but fears compensation offers will dwindle once the media spotlight shifts elsewhere.
The bitterest irony of the crisis that has destroyed their lives, he says, is that this rural area, 250 km from Tokyo, sees not a single watt of the electricity produced by the Fukushima plant.
As you can see from this image The drywell is outside the much vaulted impervious containment vessel. The media is incorrectly using drywell and containment vessel interchangeably.
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12:02 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
Fukushima 'Full Meltdown' Made Official By Adam Clark Estes May 12, 2011
TEPCO officials confirmed today the months-long of suspicion that the Reactor No. 1 at Fukushima suffered a full meltdown. According to the disclosure today, workers discovered earlier this week that No. 1's containment vessel has been leaking water and today discovered a sizeable hole they believe was created by fallen fuel pellets. The water leakage not only indicates that the clean up efforts will take longer than originally expected but also that the worst case scenario was already underway when TEPCO said it had been avoided.
Before anybody panics over the very scary phrase "full meltdown," it's worth pointing out that nuclear scientists don't necessarily agree on what that means. The difference between a "partial meltdown," which is what we were lead to believe had happened, and a "full meltdown," which is the term dominating today's headlines, is unclear and perhaps not even that important. According to Columbia's David Brenner, a "full meltdown" occurs when the exposed fuel melts through the bottom of the containment vessel. That's not the dangerous part, though. When asked in an interview about the danger of meltdowns, Brenner said:
They’re certainly not good. You can contrast the two major nuclear incidents of the past: Both Chernobyl and Three Mile Island were meltdowns, but the difference in scale is enormous. Chernobyl was the equivalent of 1 million Three Mile Islands. A “meltdown” certainly is not a good thing, but the ultimate consequence is how much radioactivity is released into the environment. You can have a situation like Three Mile Island, where it’s extremely small amount, or a situation like Chernobyl.
The Fukushima disaster is already as bad as Chernobyl according to the International Atomic Energy Association's scale, but the radiation levels released are yet to be determined. Semantics and classifications aside, the people of Japan's situation is scarier than before for one reason: that big hole that's leaking radioactive water puts a serious damper TEPCO's plan to cool the reactor by dousing it with water. Even if they plug the leak, it's unclear how much more radioactive water has seeped into the ground or ocean around the plant. This is the third leak discovered by officials, and it may very well not be the last. Sources
* Fukushima reactor has a hole, leading to leakage, Yoko Kubota and Scott DiSavino, Reuters * Japan Nuclear Crisis: What Is a Full Meltdown?, Josh Dzieza, The Daily Beast * Nuclear meltdown at Fukushima plant, Julian Ryall, Daily Telegraph
"We've heard five, maybe 10 years, but some say that's far too optimistic," he said, crying. "Maybe I'll be able to come home to die."
Like many in the area, Shoji, whose family has been farming this land since the 1880s, is too old to become embroiled in a protracted legal battle with Tepco or the government.
The bitterest irony of the crisis that has destroyed their lives, he says, is that this rural area, 250 km from Tokyo, sees not a single watt of the electricity produced by the Fukushima plant.
[This message has been edited by JazzMan (edited 05-13-2011).]
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01:32 PM
Raydar Member
Posts: 40712 From: Carrollton GA. Out in the... country. Registered: Oct 1999
Won't stop the rods from melting into the ground, they dug down in chernobyl and froze the molten blob, then sealed it in sand and concrete. Then concreted over the crap.
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05:29 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
The operator of the Fukushima Daiichi nuclear power plant is trying to locate thousands of tons of radioactive water that has leaked from one of the damaged reactors.
Tokyo Electric Power Company, or TEPCO, says contaminated water is apparently leaking from the No.1 reactor, which is in a state of meltdown.
TEPCO has injected more than 10,000 tons of water into the reactor since the March 11th disaster damaged the plant. But, less than half that amount is believed to remain in the reactor or its container vessel.
The utility says the leaked water is likely in the basement of the reactor building -- still a no-go zone due to concerns over high radiation levels.
TEPCO is considering using remote-controlled robots to check the situation, but says the wireless links needed to control them may not reach the basement and that it has to explore other options as well.
Injected water is continuing to stabilize the reactor, but any radioactive water that has leaked could hamper the effort.
TEPCO says it hopes to come up with ways to retrieve and purify contaminated water to use it to cool the reactor again.
Won't stop the rods from melting into the ground, they dug down in chernobyl and froze the molten blob, then sealed it in sand and concrete. Then concreted over the crap.
Here is a much more accurate account of what they did at Chernobyl.
"froze the blob" - that one make me chuckle
==
Edit
If the fuel rods are melted, they are no longer 'rods'
[This message has been edited by phonedawgz (edited 05-13-2011).]
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11:46 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
Here is a much more accurate account of what they did at Chernobyl.
"froze the blob" - that one make me chuckle
==
Edit
If the fuel rods are melted, they are no longer 'rods'
Can't attack the argument so you attack the person again? Molten blob is as good as a description as anything. You have been downplaying this the whole time, and mocking anyone who disagrees. Everyone understood molten blob = melted fuel rods, and yes once they are melted they are no long rods.
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11:57 PM
May 14th, 2011
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
It's not my intention to downplay the disaster. It is something to take seriously. I have attacked NUMEROUS wacko things that have been posted.
Really? Maybe you should do research outside of wikipedia.... "It took more than a week before a viable plan to stop the uncontrolled release of raw radioactive material into the environment was formulated. It took another two days to make it happen after the plans were put into effect. Tons upon tons of liquid nitrogen were continually pumped into the massive catacomb-like support area below the floor of the reactor compartment, eventually freezing the completely destroyed reactor fuel cell. By freezing the area, the flow of radioactive gasses ceased. After the radioactive gas flow ceased, workers kept pumping in liquid nitrogen while hundreds upon hundreds of truckloads of fresh, wet concrete were poured into and on top of the reactor compartment, as well as the rest of the decimated building. On the 15th day of the Chernobyl accident, the enormous concrete mass had fully set up and solidified, so the liquid nitrogen was no longer needed." http://www.hiroshimasyndrome.com/chernobyl.html
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12:37 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
A plan was devised: to freeze the earth around the reactor with liquid nitrogen, and then build a heat exchanger in the ground beneath it to cool the core and prevent meltdown. Prianichnikov himself was sent in with temperature and radiation probes to discover how long they had before the core burned through the two metres of concrete foundations; meanwhile, miners were summoned from the coalfaces of Donetsk and the subway projects in Kiev to dig tunnels beneath the reactor. The scientists feared that pneumatic drills could disturb the foundations of the reactor, so they worked with hand tools, in conditions where wearing protective clothing was practically impossible, amid extraordinary fields of radioactivity. To freeze the ground, all the liquid nitrogen in the western Soviet Union was sent to Chernobyl: when it didn't arrive quickly enough, director Brukhanov received a late-night telephone call from the minister in charge of the operation. 'Find the nitrogen,' he was told, 'or you'll be shot.'
On 10 May, the fire finally subsided; it now seems possible that the graphite simply burnt itself out. The nitrogen was found, and the subterranean heat exchanger built, but by mid-May the temperature of the core had dropped to 270C; the exchanger was never even turned on. 'The miners died for nothing,' says Prianichnikov. 'Everything we did was a waste of time.'
When I ask him if he received any recognition for what he did, Prianichnikov smiles darkly. 'I didn't go to court, and I wasn't put in prison. That was the recognition I received.'
btw - what the rest of your article said is kinda interesting
"Although no cancer epidemic nor any other negative long term health effects in the exposed population have occurred in more than two decades, hindsight analysis of the accident at Chernobyl demonstrates that the RBMK reactor system should never, ever have had the remotest chance of operating. The fifty who actually died fighting the fires and radiation releases would have lived their natural lives and the 5 million people in the surrounding population would not have been subjected to nearly 25 years of fear exacerbated by the Hiroshima Syndrome. A reactor designed to operate on Positive Temperature (PTE) and Steam Effects (PSE) should not have been built...ever! Even though no long term health effects due to radiation exposure have occurred in the surrounding public, the horrific way Chernobyl was reported to the world in 1986, combined with a wide range of speculations of up to a million cancer deaths produced by Chernobyl around the world, unleashed the psychic effects of the Hiroshima Syndrome in large populations outside America. Because of Chernobyl, the psychological damage of the Hiroshima Syndrome swelled beyond the borders of America and engulfed the entire planet. For all intents and purposes, it still does."
[This message has been edited by phonedawgz (edited 05-14-2011).]
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06:15 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
btw - what the rest of your article said is kinda interesting
"Although no cancer epidemic nor any other negative long term health effects in the exposed population have occurred in more than two decades, hindsight analysis of the accident at Chernobyl demonstrates that the RBMK reactor system should never, ever have had the remotest chance of operating. The fifty who actually died fighting the fires and radiation releases would have lived their natural lives and the 5 million people in the surrounding population would not have been subjected to nearly 25 years of fear exacerbated by the Hiroshima Syndrome. A reactor designed to operate on Positive Temperature (PTE) and Steam Effects (PSE) should not have been built...ever! Even though no long term health effects due to radiation exposure have occurred in the surrounding public, the horrific way Chernobyl was reported to the world in 1986, combined with a wide range of speculations of up to a million cancer deaths produced by Chernobyl around the world, unleashed the psychic effects of the Hiroshima Syndrome in large populations outside America. Because of Chernobyl, the psychological damage of the Hiroshima Syndrome swelled beyond the borders of America and engulfed the entire planet. For all intents and purposes, it still does."
Melting rods does = meltdown, no matter how you want to spin it. As far as the nitrogen they did apply some of it, just didn't get the majority of it in time. They did freeze the ground where molten fuel rods were, read the article. As far as no long term of effects that is merely the authors opinion, just about everyone disagrees to some extent. Aside from maybe you.
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07:26 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
A worker collapses at the Fukushima nuclear reactor No 1 and later dies, bringing the death toll to three as protests against nuclear power are held in Tokyo.
TOKYO: A worker died at Japan's disaster-stricken Fukushima Daiichi nuclear power plant on Saturday as emergency crews continued their operations to prevent a major meltdown, the plant's operator said. The male worker in his 60s was confirmed dead after he was rushed to hospital after falling unconscious at the plant, Tokyo Electric Power Co said. He is the third worker to have died in the aftermath.
When he was taken ill, the unidentified worker was carrying chainsaws with another worker inside a facility to treat contaminated water being released from the plant's crippled reactors, the official said.
"He was exposed to 0.17 millisieverts of radiation during the work. But, as he was wearing protective gear, no radioactive substances were detected on his body," Mori said, adding there were no signs of injury on the worker. "We have yet to determine the cause of his death," the official added. http://timesofindia.indiati...icleshow/8333678.cms
[This message has been edited by dennis_6 (edited 05-14-2011).]
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10:06 PM
May 15th, 2011
RandomTask Member
Posts: 4539 From: Alexandria, VA Registered: Apr 2005
Really? Maybe you should do research outside of wikipedia.... "It took more than a week before a viable plan to stop the uncontrolled release of raw radioactive material into the environment was formulated. It took another two days to make it happen after the plans were put into effect. Tons upon tons of liquid nitrogen were continually pumped into the massive catacomb-like support area below the floor of the reactor compartment, eventually freezing the completely destroyed reactor fuel cell. By freezing the area, the flow of radioactive gasses ceased. After the radioactive gas flow ceased, workers kept pumping in liquid nitrogen while hundreds upon hundreds of truckloads of fresh, wet concrete were poured into and on top of the reactor compartment, as well as the rest of the decimated building. On the 15th day of the Chernobyl accident, the enormous concrete mass had fully set up and solidified, so the liquid nitrogen was no longer needed." http://www.hiroshimasyndrome.com/chernobyl.html
They dug under the core in fear it would reach the water table, but never put LN2 in it like planned - they just filled it with concrete. Second, you're comparing apples to pluto - the reactors are completely different. Chernobyl also had a meltdown post mortem. The reactor exploded, spewing core material everywhere, lost all sort of mechanical abilities (including cooling) which caused the remaining fuel to melt.
Second - If the reactor did break the steel containment, its still in the CONTAINMENT system, just not primary, (secondary). I really wish you would understand the design intent of this reactor instead of propagating doomsday articles ie articles that would like to insuate that radiation is killing the people at the plant (lets forget the HUGE tsunami or the fact that the third death wasn't related to radiation)
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12:30 AM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
Mori said, adding there were no signs of injury on the worker. "We have yet to determine the cause of his death," the official added.
quote
Originally posted by dennis_6:
A worker collapses at the Fukushima nuclear reactor No 1 and later dies, bringing the death toll to three as protests against nuclear power are held in Tokyo.
Clearly if the cause of his death is unknown then the death toll is not yet 3.
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12:38 AM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
Your point is? I am pro nuclear power, and I wish i could afford a small private reactor to power my home. i do believe they are the future and Thorium reactors address part of the nuclear waste issue. I just believe in a disaster they should be truthful, in any disaster nuclear or not. I don't like spin positive or negative, and that is all that is out there right now. I am equally pissed at the people stating nothing happened as those stating this is the end of the world.
As far as the link I did post it, you stated it couldn't go chernobyl because it wasn't a graphite reactor and had a contaiment vessel. Then we got in an argument about the containment vessel. If people follow the link anyone with an IQ of 2 could figure out what you were suggesting.
[This message has been edited by dennis_6 (edited 05-15-2011).]
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12:57 AM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
Graphite burns. Burning graphite mixed with a melted radioactive core launches radioactive particles into the atmosphere. Last I checked water doesn't burn.
This reactors core is located inside a containment vessel. The core could melt and there still could not be the release of radioactive particles.
What this means is the core COULD melt and there still COULD be no release of radioactive particles. This does not mean that there is no possibility of a breach of containment.
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01:08 AM
PFF
System Bot
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
What this means is the core COULD melt and there still COULD be no release of radioactive particles. This does not mean that there is no possibility of a breach of containment.
Play on words, the average person would take that as non russian reactors can't breach containment.
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01:14 AM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
TOKYO—Substantial damage to the fuel cores at two additional reactors of Japan's Fukushima Daiichi nuclear complex has taken place, operator Tokyo Electric Power Co. said Sunday, further complicating the already daunting task of bringing them to a safe shutdown while avoiding the release of high levels of radioactivity. The revelation followed an acknowledgment on Thursday that a similar meltdown of the core took place at unit No. 1.
View Full Image 0515tepco European Pressphoto Agency
Junichi Matsumoto, an official of Tokyo Electric Power Co. listens to questions during a press conference regarding the meltdown of Fukushima Daiichi nuclear power plant at the company headquarters in Tokyo, Japan, May 13, 2011. 0515tepco 0515tepco
Workers also found that the No. 1 unit's reactor building is flooded in the basement, reinforcing the suspicion that the containment vessel is damaged and leaking highly radioactive water.
The revelations are likely to force an overhaul of the six- to nine-month blueprint for bringing the reactors to a safe shutdown stage and end the release of radioactive materials. The original plan, announced in mid-April, was due to be revised May 17.
The operator, known as Tepco, said the No. 1 unit lost its reactor core 16 hours after the plant was struck by a magnitude-9 earthquake and a giant tsunami on the afternoon of March 11.
The pressure vessel a cylindrical steel container that holds nuclear fuel, "is likely to be damaged and leaking water at units Nos. 2 and 3," said Junichi Matsumoto, Tepco spokesman on nuclear issues, in a news briefing Sunday.
He also said there could be far less cooling water in the pressure vessels of Nos. 2 and 3, indicating there are holes at the bottom of these vessels, with thousands of tons of water pumped into these reactors mostly leaking out.
Tepco found the basement of the unit No. 1 reactor building flooded with 4.2 meters of water. It isn't clear where the water came from, but leaks are suspected in pipes running in and out of the containment vessel, a beaker-shaped steel structure that holds the pressure vessel.
The water flooding the basement is believed to be highly radioactive. Workers were unable to observe the flooding situation because of strong radiation coming out of the water, Tepco said.
A survey conducted by an unmanned robot Friday found radiation levels of 1,000 to 2,000 millisieverts per hour in some parts of the ground level of unit No. 1, a level that would be highly dangerous for any worker nearby. Japan has placed an annual allowable dosage limit of 250 millisieverts for workers.
The high level of radioactivity means even more challenges for Tepco's bid to set up a continuous cooling system that won't threaten radiation leaks into the environment.
Tepco separately released its analysis on the timeline of the meltdown at unit No. 1. According to the analysis, the reactor core, or the nuclear fuel, was exposed to the air within five hours after the plant was struck by the earthquake. The temperature inside the core reached 2,800 degrees Celsius in six hours, causing the fuel pellets to melt away rapidly.
Within 16 hours, the reactor core melted, dropped to the bottom of the pressure vessel and created a hole there. By then, an operation to pump water into the reactor was under way. This prevented the worst-case scenario, in which the overheating fuel would melt its way through the vessels and discharge large volumes of radiation outside.
The nuclear industry lacks a technical definition for a full meltdown, but the term is generally understood to mean that radioactive fuel has breached containment measures, resulting in a massive release of fuel.
"Without the injection of water [by fire trucks], a more disastrous event could have ensued," said Mr. Matsumoto.
Tepco also released its analysis of a hydrogen explosion that occurred at unit No. 4, despite the fact that the unit was in maintenance and that nuclear fuel stored in the storage pool was largely intact.
According to Tepco, hyrogen produced in the overheating of the reactor core at unit 3 flowed through a gas-treatment line and entered unit No. 4 because of a breakdown of valves. Hydrogen leaked from ducts in the second, third and fourth floors of the reactor building at unit No. 4 and ignited a massive explosion.
The funny thing is they are trying to say containment is intact, yet admit radioactive water is leaking into the basement from the reactor itself, which would indicate there is no longer containment. They pump it into the core, where it leaks to the containment vessel, where it leaks to the drywell, and then leaks into the basement. That doesn't exactly add up. At least this article addressed the containment vessel breach.
1000 milisieverts = 100 rads and 2000 millisieverts = 200 rads. This is not low level radiation, 1 hr at these levels would most likely give you radiation sickness 2-3hrs may be fatal.
[This message has been edited by dennis_6 (edited 05-15-2011).]
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02:44 PM
phonedawgz Member
Posts: 17091 From: Green Bay, WI USA Registered: Dec 2009
A 30-year-old solar panel installer, Richard P.* died after he fell 45 feet off the roof of a three-story apartment building. He was part of a three-man crew working to install solar panels on a sloped roof. Richard walked backward and stepped off the roof while checking the position of some brackets. No one was wearing personal fall protection equipment and there was no other fall protection system in place.
Posted 33 minutes ago Official in protective gear talks to a woman
Tens of thousands who have already been forced out of their homes by the nuclear crisis. (Reuters: Kim Kyung-Hoon)
* Related Story: Japan agrees on nuclear compensation scheme * Related Story: Worker dies at Japan's crippled nuclear plant
Japan began evacuating people from outside the official exclusion zone around the crippled Fukushima nuclear plant after it was revealed fuel rods there probably melted hours after March's devastating earthquake.
With radiation levels remaining high, small children and pregnant women were the first to be moved, with thousands more to be shifted into shelters and temporary housing.
More details have emerged about the meltdown in Fukushima's No. 1 reactor, with revelations the fuel rods were likely exposed to the air for as long as 14 hours - a fact not discovered until last week.
It appears the rods melted just hours after the earthquake and tsunami struck, dropping to the bottom of the pressure vessel at the core.
It was the news the people of Litate village had been dreading.
A touch further than 30 kilometres from the Fukushima plant, Litate was outside the evacuation zone until now.
Because of wind patterns, Litate and nearby communities have been swathed in high radiation and authorities are not willing to let people stay any longer.
"I'm sure most of you have lived in this village all your lives and have never planned on moving," mayor Norio Kanno told residents.
"To those of you that I now have to ask to pack up and leave your homes, I am deeply sorry."
After the plant's operator, TEPCO, told the Japanese people that things were stabilising at Fukushima, it is now clear they knew far less about the situation than they were willing to admit.
About 8,000 Litate residents and those in the nearby village of Kawamata are being asked to move, joining the tens of thousands who have already been forced out of their homes by the nuclear crisis.
They will be put up in hotels, public housing and evacuation shelters, and no-one knows when they will be allowed to return.
"It's such an incredible shame to have to leave the house I've lived in for so long," one elderly resident said.
Two Solar Energy Installers Die From Electrical and Fall Hazard
The California Fatality Assessment and Control Evaluation (CA/FACE) program tracks and investigates cases of fatal injuries at work, and makes prevention recommendations for employers and employees. In the past year, the death of two solar energy installers has highlighted the need for all solar energy companies to review current workplace safety programs and be sure those programs include assessments for electrical and fall hazards.
The first worker was electrocuted and fell to his death off a scaffold after a 20-foot metal bracket made contact with a nearby high voltage power line. A hazard analysis of the worksite had not been performed before work was started, and the victim had not received specific training on high voltage electrical hazards. The second worker fell through a roof skylight after he tripped while carrying solar panels. Although a hazard assessment of the worksite had been performed before starting work, the skylight was not guarded and the victim was not wearing personal fall protection. A complete report with safety recommendations about the first incident (#08CA006) is available:
A 30-year-old solar panel installer, Richard P.* died after he fell 45 feet off the roof of a three-story apartment building. He was part of a three-man crew working to install solar panels on a sloped roof. Richard walked backward and stepped off the roof while checking the position of some brackets. No one was wearing personal fall protection equipment and there was no other fall protection system in place.
A 30-year-old solar panel installer, Richard P.* died after he fell 45 feet off the roof of a three-story apartment building. He was part of a three-man crew working to install solar panels on a sloped roof. Richard walked backward and stepped off the roof while checking the position of some brackets. No one was wearing personal fall protection equipment and there was no other fall protection system in place.
Due to widespread contamination from the solar panel the apartment complex and a surrounding 20 mile radius were forcibly evacuated and declared an exclusion zone. Officials are saying that cleanup may begin within a year. No word on when any of the 60,000 plus residents in the exclusion zone will, if ever, be allowed to return to their homes and start rebuilding their lives. The solar panel installer only had a fraction of the financial resources and assets needed for remediation costs and compensation to the now homeless evacuees and will likely declare bankruptcy, leaving the victims in the hole with nothing.
Yeah, we should ban solar power, it's just too dangerous and expensive to deal with if something goes awry.
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12:33 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
Neutron beam observed 13 times at crippled Fukushima nuke plant
TOKYO, March 23, Kyodo
Tokyo Electric Power Co. said Wednesday it has observed a neutron beam, a kind of radioactive ray, 13 times on the premises of the Fukushima Daiichi nuclear plant after it was crippled by the massive March 11 quake-tsunami disaster.
TEPCO, the operator of the nuclear plant, said the neutron beam measured about 1.5 kilometers southwest of the plant's No. 1 and 2 reactors over three days from March 13 and is equivalent to 0.01 to 0.02 microsieverts per hour and that this is not a dangerous level.
The utility firm said it will measure uranium and plutonium, which could emit a neutron beam, as well.
In the 1999 criticality accident at a nuclear fuel processing plant run by JCO Co. in Tokaimura, Ibaraki Prefecture, uranium broke apart continually in nuclear fission, causing a massive amount of neutron beams.
In the latest case at the Fukushima Daiichi nuclear plant, such a criticality accident has yet to happen.
But the measured neutron beam may be evidence that uranium and plutonium leaked from the plant's nuclear reactors and spent nuclear fuels have discharged a small amount of neutron beams through nuclear fission.
==Kyodo
Missed this back in march, but it sounds like there have been a few excursions. This also indicates full meltdown back in march, Uranium or Plutonium had to be exposed or the shielding would have blocked the neutron beams. So we have intermittent fission and exposed core back in March.
[This message has been edited by dennis_6 (edited 05-16-2011).]
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12:48 PM
PFF
System Bot
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
Now Tepco says they are still on schedule despite meltdown and the cores are almost in cold shut down. lol They might want to look for the fuel outside the core.
Now Tepco says they are still on schedule despite meltdown and the cores are almost in cold shut down. lol They might want to look for the fuel outside the core.
I take all deaths seriously. I also consider all risk with their likelihood of happening.
Packers great Max McGee fell off of his roof and died. Roofs are dangerous places to be.
I think we can all agree that Nuclear power for the most part is a very safe way to produce electricity but IMO the rub comes when you have to consider the impact of a worse case scenario like Fukushima or Chernobyl. You are not only dealing with the statistics of deaths or injury you have to consider the environmental and emotional impacts that can last for decades. Radiation has a major impact on peoples psyche due to it's ability to contaminate areas without being easily detected by residents and the fact that it can remain contaminated for such a long time thereby disrupting a segment of population long term. Then you have the added fear of it being canceer causing which is a major phobia of the public as well. Other energy sources don't have the same perceived negative impact when major accidents occur.
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03:35 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
Doubt that is actually possible, It can melt into the earth, but not all the way to the other side.
Yeah, Chernobyl and Fukushima aren't really the true "worst case scenario", not by a long shot, even though they're both rated a 7 on a 7-point scale. In a true worst-case scenario the molten fuel would melt its way down to the water table and produce an on-going geyser explosion of steam and isotopes that would spread long-lasting contamination over thousands of square miles. Iodine would go away in a fairly short time but cesium, plutonium, strontium, uranium, etc, would linger for centuries if not millennia, rendering habitable and farming lands permanently unusable for what amounts to eternity. If/when that happens, and I say "when" simply because nobody's managed to engineer a truly fail-proof system so far in human history, the likely result will be that we will simply declare the region a dead zone and learn to live without it. Alternatively, we will adopt a new normal where some level of contamination of food and land will be acceptable and any premature deaths resulting from that will be accepted as the "cost of civilization". Sort of like it being better to ask forgiveness rather than permission.
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11:09 AM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
Yeah, Chernobyl and Fukushima aren't really the true "worst case scenario", not by a long shot, even though they're both rated a 7 on a 7-point scale. In a true worst-case scenario the molten fuel would melt its way down to the water table and produce an on-going geyser explosion of steam and isotopes that would spread long-lasting contamination over thousands of square miles. Iodine would go away in a fairly short time but cesium, plutonium, strontium, uranium, etc, would linger for centuries if not millennia, rendering habitable and farming lands permanently unusable for what amounts to eternity. If/when that happens, and I say "when" simply because nobody's managed to engineer a truly fail-proof system so far in human history, the likely result will be that we will simply declare the region a dead zone and learn to live without it. Alternatively, we will adopt a new normal where some level of contamination of food and land will be acceptable and any premature deaths resulting from that will be accepted as the "cost of civilization". Sort of like it being better to ask forgiveness rather than permission.
Far more feasible than "China Syndrome"
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12:22 PM
dennis_6 Member
Posts: 7196 From: between here and there Registered: Aug 2001
Plan to flood Fukushima reactor could cause new blast, experts warn
Plant operator Tepco reveals meltdown and breach of pressure vessel, with Greenpeace warning against pumping water in
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* Justin McCurry in Tokyo * guardian.co.uk, Friday 13 May 2011 12.23 BST * Article history
A worker inside the No 1 reactor building at Fukushima Daiichi nuclear power plant A worker inside the No 1 reactor building at Fukushima Daiichi nuclear power plant. Photograph: AP
Experts have warned of a potentially dangerous radiation leak if Japan proceeds with plans to flood a damaged reactor containment vessel at the Fukushima Daiichi nuclear plant. The facility's operator has admitted uranium fuel rods in the No 1 reactor partially melted after being fully exposed because of the 11 March tsunami.
Tokyo Electric Power (Tepco) said water levels had fallen to at least one metre below four-metre-long fuel rods inside the reactor core and melted fuel had slumped to the bottom of the reactor's containment vessel.
The damage is more severe than Tepco had previously reported and is almost certain to frustrate its quest to bring the plant under control within six to nine months. Officials said the leaked fuel was being kept cool and there was no risk of an explosion of the kind that blew the roof off the reactor in March.
The discovery was made after engineers were able to enter the reactor building, where they adjusted water gauges, for the first time since the plant was crippled by the earthquake and tsunami.
Officials said initial findings indicated a large leak in the pressure vessel but temperatures remained well below dangerous levels.
"There must be a large leak," Junichi Matsumoto, a general manager at the utility, told reporters. "The fuel pellets likely melted and fell, and in the process may have damaged the pressure vessel itself and created a hole."
Nuclear safety official Takashi Sakurai said: "The situation in the core hasn't changed [since early in the crisis] and the fuel rods are being cooled by water continuously being injected into the core."
Japan's nuclear safety agency said it believed partially melted fuel had fallen to the bottom of the pressure vessel, which holds the reactor core together, and may have leaked into its concrete base, known as the dry well.
Greenpeace has urged Tepco to abandon plans to flood the container with water, given the likelihood that melted fuel has damaged it. Shaun Burnie, nuclear adviser to Greenpeace Germany, said: "Flooding a reactor that has fuel [that has fallen] through the pressure vessel is not a good idea."
Outlining a worst-case scenario, Burnie said very large amounts of cold water hitting the melted fuel could cause an explosion, trigger substantial damage to the reactor and create a "high risk of atmospheric release running for days, if not weeks." He added: "I think [the flooding option] will now be scrapped."
Greenpeace said problems could escalate rapidly if the fuel melted through the reactor vessel. "As the fuel rods were fully exposed and subsequently melted, it is highly likely that the core's integrity is compromised and that there is larger amount of melted fuel at the bottom of the reactor pressure vessel." John Large, an independent nuclear engineering consultant in London, said Tepco's plan to flood the reactor was riddled with "potential risks". It appeared not to have factored in the extent of damage to the fuel rods and the structural state of the containment vessel, including whether it was watertight. "It seems to be poorly thought through," he said, adding that the firm had not demonstrated that the strategy could work.
Matsumoto ruled out a possible explosion but said: "We have to revise the flooding method. We can't deny the possibility that a hole in the pressure vessel caused water to leak."
The use of water to keep the reactors cool has led to the build-up of about 70,000 tons of contaminated water at Fukushima Daiichi. Tepco is pumping the water into a nearby storage building while it sets up a decontamination system.
Cooling water has leaked from the cores of reactors 2 and 3. One other unit at Fukushima Daiichi did not contain fuel rods at the time of the earthquake, while another two have achieved "cold shutdown" – their cooling water is below boiling point.
The permanent or temporary shutdown of reactors at Fukushima Daiichi and other nuclear plants could leave only a third of Japan's 54 reactors in operation by the end of the month, NHK has reported.
The public broadcaster said the disaster had prompted the suspension of 14 reactors, while 19 others were offline for inspections. Two reactors at Hamaoka nuclear plant in central Japan are to be shut while a tsunami wall is built.
The prime minister, Naoto Kan, has ordered the temporary closure of Hamaoka, which sits on an active fault line, amid warnings that it could be crippled by another huge earthquake expected to hit the region in the next 30 years.
In all 35 reactors – or about two-thirds of Japan's total – will have been shut down by the end of May. Officials are hoping to achieve a 15% cut in energy use during the summer to avoid rolling blackouts.
The government has decided to use taxpayers' money to help Tepco compensate tens of thousands of people affected by the Fukushima accident. Total damages are expected to run into trillions of yen, equating to tens of billions of pounds.
Reports said the government would issue special-purpose bonds worth 5tn yen (£37bn), with other utilities asked to pay into a newly established fund. Tepco would be required to contribute annual premiums and allow monitoring of its management by a government-appointed commission.
Analysts said the scheme would ensure Tepco's status as a listed firm and prevent market instability, although there are fears that the costs will be passed on to consumers in the form of higher electricity bills.
"This scheme will help alleviate concerns of financial market turmoil because holders of Tokyo Electric shares and bonds will be protected," Yasuhide Yajima, a senior economist at the NLI Research Institute, told Reuters. http://www.guardian.co.uk/w...own-flooding-warning
