quote Originally posted by dennis_6: Phonedawgz that is a list of your failures. Anybody who is following this can see where i proved you wrong. Only the plutonium story did i mix up and unlike you I Admitted I was wrong.

Well at least on ONE point you have wised up. Good to see that you finally gave up trying to cover up your mistake by arguing that since they are both alpha emitters, they must have similar toxicity.

quote Originally posted by dennis_6: Got me on that technicality, however I would say that still raises a reasonable doubt that salt is just as dangerous as Plutonium, remember the polonium was not inhaled.

https://www.fiero.nl/forum/F...083464-29.html#p1132

quote Originally posted by phonedawgz: You're seriously going to try to make some argument that the toxicity of polonium has anything to do with the toxicity of plutonium?

[This message has been edited by phonedawgz (edited 12-01-2011).]

Study Shows Worse Picture of Meltdown in Japan
By HIROKO TABUCHI
Published: November 30, 2011

TOKYO — Molten nuclear fuel may have bored into the floor of at least one of the reactors at the stricken Fukushima Daiichi nuclear power plant, the complex’s operator said Wednesday, citing a new simulation of the accident that crippled the plant in March.
Related

*
Report Gives New Details of Chaos at Stricken Plant (November 12, 2011)
*
Times Topic: Japan — Earthquake, Tsunami and Nuclear Crisis (2011)

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The simulation suggested that the meltdown may have been more severe than had previously been thought.

Soon after an earthquake and a tsunami on March 11 knocked out cooling systems at the power plant, nuclear fuel rods in three of its six reactors overheated and slumped, the operator, the Tokyo Electric Power Company, has said.

In the No. 1 reactor, the overheated fuel may have eroded the primary containment vessel’s thick concrete floor, and it may have gotten almost within a foot of a crucial steel barrier, the utility said the new simulation suggested. Beneath that steel layer is a concrete basement, which is the last barrier before the fuel would have begun to penetrate the earth.

Some nuclear experts have warned that water from a makeshift cooling system now in place at the plant may not be able to properly cool any nuclear fuel that may have seeped into the concrete. The new simulation may call into question the efforts to cool and stabilize the reactor, but the Tokyo Electric Power Company, or Tepco, says it is not worried more than eight months after the accident.

The findings are the latest in a series of increasingly grave scenarios presented by Tepco about the state of the reactors. The company initially insisted that there was no breach at any of the three most-damaged reactors; it later said that there might have been a breach, but that most of the nuclear fuel had remained within the containment vessels.

“This is still an overly optimistic simulation,” said Hiroaki Koide, an assistant professor of physics at the Kyoto University Research Reactor Institute, who has been a vocal critic of Tepco’s lack of disclosure of details of the disaster. Tepco would very much like to say that the outermost containment is not completely compromised and that the meltdown stopped before the outer steel barrier, he said, “but even by their own simulation, it’s very borderline.”

“I have always argued that the containment is broken, and that there is the danger of a wider radiation leak,” Mr. Koide said. “In reality, it’s impossible to look inside the reactor, and most measurement instruments have been knocked out. So nobody really knows how bad it is.”

Still, a spokesman for Tepco, Junichi Matsumoto, said Wednesday that the nuclear fuel was no longer eating into the concrete, and that the new simulation would not affect efforts to bring the reactors to a stable state known as a “cold shutdown” by the end of the year.

“The containment vessel as a whole is being cooled, so there is no change to our outlook,” Mr. Matsumoto said at a news conference.

The nuclear accident at the Fukushima Daiichi plant, the worst since Chernobyl, triggered fuel meltdowns at three of its six reactors and a huge radiation leak that has displaced as many as 100,000 people. The Japanese government has said some areas around the plant will be uninhabitable for decades.

Tepco based the simulation on projections of decay heat released by the nuclear fuel and other estimates. The results suggest that the uranium fuel rods at the No. 1 reactor were most badly damaged, Mr. Matsumoto said, because it lost cooling water before the other two reactors did. The fuel rods were exposed for several hours before fire trucks could pump in emergency seawater.

Because the simulation suggests that heat released as a result of radioactive decay “far overwhelmed” the effect of the cooling water, he said, and because temperatures in the inner pressure vessel that originally housed the fuel are thought to have dropped quickly, Tepco now assumes that “100 percent of the fuel at Unit 1 has slumped” into the outer primary containment vessel.

In addition, the simulation suggests that the fuel bored more than two feet into the concrete, Mr. Matsumoto said.

At Units 2 and 3, the initial cooling efforts were more successful, he said, and a smaller amount of fuel is thought to have escaped the pressure vessels and into the primary containment vessels.

http://www.nytimes.com/2011...se-than-thought.html

Fukushima nuclear catastrophe closer than thought

* by: Rick Wallace, Tokyo correspondent
* From: The Australian
* December 02, 2011 12:00AM


MOLTEN nuclear fuel in one reactor at Japan's stricken Fukushima Daiichi plant burned through the steel pressure vessel and three-quarters of the surrounding concrete containment vessel that formed the reactor's last substantial internal barrier.

The revelation of the near "China Syndrome" meltdown is yet another revision of the severity of the disaster following the March 11 earthquake and tsunami.
http://www.theaustralian.co...frg6so-1226211693322

[This message has been edited by dennis_6 (edited 12-01-2011).]

Fukushima's Reactor 1 Meltdown Was Worse Than We Realized

POSTED BY: Eliza Strickland / Thu, December 01, 2011




Special Report: Fukushima and the Future of Nuclear Power

Editor's Note: This is part of the IEEE Spectrum special report: Fukushima and the Future of Nuclear Power.

A new simulation of the meltdowns at the Fukushima Dai-ichi nuclear power station found that the situation was even worse than previously thought. It now appears that nearly all the nuclear fuel in reactor 1 melted through the first line of defense, the steel reactor vessel, and made a serious dent in the next protective layer.

(The analysis is only available in Japanese at this time, but we'll update the post when/if it comes out in English. The source of the figures in this post is a brief summary from World Nuclear News.)

TEPCO, the utility that owns the Fukushima plant, ran new calculations of the rate at which the nuclear fuel melted in reactors 1, 2, and 3. These three reactors were in service at the time of the 11 March earthquake and tsunami, and although they automatically shut down following the earthquake, the tsunami knocked out all power at the facility and thus prevented cooling systems from removing the nuclear fuel's residual heat.

As extensively documented in our feature article, "24 Hours at Fukushima," reactor 1 suffered the greatest breakdown. That 40-year-old reactor lost all its emergency cooling systems immediately following the tsunami, while the backup cooling systems at reactors 2 and 3 functioned for a couple of days.

The new analysis from TEPCO suggests that almost all of reactor 1's fuel melted through the steel reactor vessel and dropped down into the primary containment vessel below. (In the image above, the fuel sludge is the brown blob.) The primary containment vessel, a steel structure in the shape of an upside-down light bulb, has concrete at the bottom of the bulb. TEPCO's analysis found that the fuel melted through 70 centimeters of that concrete. However, that still left 190 centimeters of intact concrete between the melted fuel and the steel boundary of the primary containment vessel. In addition, the secondary containment building has 760 centimeters of concrete that stand between the primary containment and the earth below.

At reactors 2 and 3, the simulation found that smaller amounts of fuel melted holes in the pressure vessels and dropped down to the concrete in the primary containment vessel.

It should be noted that this information comes from a computer model of the fuel's behavior, and it may be inaccurate. With the intense levels of radiation around the reactors, there's no way yet to measure the actual location of the fuel.

But it's also worth remembering that TEPCO's earliest announcements about the Fukushima Dai-ichi accident said that there had been no melting of the nuclear fuel. Later they admitted there had been significant melt, but said the fuel had all remained in the reactor vessels. While the company has no doubt been scrambling to get accurate information in an ever-changing and extremely dangerous disaster scene, I'm looking forward to results of the Japanese government's investigation into what TEPCO knew, and when they knew it.
http://spectrum.ieee.org/te...rse-than-we-realized

[This message has been edited by dennis_6 (edited 12-01-2011).]

Fukushima fuel rods eating through solid concrete

By North Asia correspondent Mark Willacy

Updated December 02, 2011 08:08:11

The findings indicate that Fukushima came much closer to a cataclysmic meltdown than previously thought.

Molten fuel rods at the Fukushima nuclear plant may have eaten two-thirds of the way through a concrete containment base, the plant's operator says.

The statement from TEPCO is based on a new simulation of the March meltdowns.

It says its latest calculations suggest the nuclear fuel inside the number one reactor has melted entirely.

Simulations predict the molten fuel has eaten through 65 centimetres of concrete in a containment base below, stopping just 37 centimetres short of an outer steel casing.

It is also believed that the molten core has eaten part of the way through the concrete bases of the number two and three reactors.

The findings indicate the facility came much closer to a cataclysmic meltdown than previously thought.

The operator's assessment comes about six months after international nuclear experts warned that molten fuel could eat through containment vessels below the reactors.

http://www.abc.net.au/news/...7916/?site=newcastle

All N-fuel may have fallen to outer vessel / TEPCO: Up to 68 tons likely melted in No. 1 reactor, eroding concrete of containment unit

The Yomiuri Shimbun

Almost all the nuclear fuel inside the No. 1 reactor of the crippled Fukushima No. 1 nuclear power plant has melted, damaging the pressure vessel and eroding the concrete bottom of the containment vessel by up to 65 centimeters, the plant's operator has found.

Tokyo Electric Power Co. released its latest analysis Wednesday on the cores of the plant's Nos. 1 to 3 reactors, based on temperature, water levels and other data. TEPCO said the fuel inside the reactors has melted to various degrees following the March 11 earthquake and tsunami.

The No. 2 reactor's fuel is up to 57 percent melted, while that of the No. 3 reactor is up to 63 percent melted, TEPCO's analysis has shown.

TEPCO has made the latest analysis to judge to what degree the fuel has cooled, as well as to ascertain if it can achieve its year-end target of a cold shutdown of the reactors, as stipulated in the timetable the utility company and the government have compiled to bring the nuclear crisis under control.

Following the March 11 earthquake and tsunami, water injection at the No. 1 reactor was suspended for about 14 hours, resulting in damage more serious than in the Nos. 2 and 3 reactors, which had water injection suspended for six to seven hours, according to TEPCO.

The nuclear fuel at the No. 1 reactor melted as its temperature reached nearly 3,000 C at one time, TEPCO estimated. In the No. 1 reactor, TEPCO believes, almost all of the about 68 tons of fuel melted. This has not only seriously damaged the bottom of the steel pressure vessel enough to create holes, but the fuel has also fallen to the concrete bottom of the containment vessel, eroding it by up to 65 centimeters.

Only 37 centimeters of concrete remains between the fuel and the vessel's outermost steel wall in the most damaged area, TEPCO said.

Without water, the No. 1 reactor's fuel temperature was more than high enough to have melted everything inside the pressure vessel, not only the fuel itself but also the fuel control rods, the utility said.

TEPCO currently maintains a steady supply of water to the three reactors, enabling the No. 1 reactor to always have about 40 centimeters of cool water at the bottom of the containment vessel, enough to cover the melted fuel, according to the utility.

Both the government and the utility said the three reactors are experiencing no problems in maintaining cooling functions.

However, the melted fuel likely will be a major hurdle in removing fuel from the troubled reactors in the decommissioning process, which is expected to take more than 30 years.
(Dec. 2, 2011)
http://www.yomiuri.co.jp/dy...al/T111201006092.htm

[This message has been edited by dennis_6 (edited 12-01-2011).]

quote Fukushima fuel rods eating through solid concrete http://www.abc.net.au/news/...7916/?site=newcastle

It sure makes the story much more 'interesting' when the wrong tense of a word is intentionally misused in the headline.

quote Originally posted by phonedawgz: It is quite indicative of the poor quality of technical reporting to see the many versions of the same story. Some report the outcome of the simulation as matter of fact of conditions inside the reactor. Some reports drop many the qualifier words that apparently were in the simulation report. The amount of concrete to the steel casing varies in the stories. ---- I guess the news story wouldn't have been as good if the headline read: "Concrete containment floor preforms as designed in worst case computer simulation"

The computer simulation is what Tepco has been using to say everything is ok, all this time. This is not a java script simulation, its a westing house simulation. The instrumentation inside the reactor is destroyed, and the reactors are far too hot for anyone to get near.

New analysis of Fukushima core status


30 November 2011
A new analysis of the accident at Fukushima Daiichi indicates more extensive melting probably occurred at unit 1 than previously thought, although the predicted status of units 2 and 3 remains about the same.


The likely states of Fukushima Daiichi 1 (topt), as well as 2 and 3 (bottom). Water is injected via the main feedwater line, while units 2 and 3 benefit from the core spray that has helped reduce temperatures considerably

1


2&3



The bulk of unit 1's nuclear fuel went through the bottom of the reactor vessel as well as about 70 centimetres of the drywell concrete below, according to the analysis released today. However, the corium did not breach the steel containment vessel 1.9 metres further down within the concrete, or the boundary of secondary containment some 7.6 metres further still.

Of the 10.2 metres of solid concrete that makes up the floor of the reactor building, the corium is thought to have melted and mixed with the first 70 centimetres only. The natural spreading and expansion of the corium, plus the addition of compounds of concrete, would have reduced the intensity of the heat produced until it reached an equilibrium and solidified in place. Tepco said it was confident the melting had ceased due to the absence of gases that would be released by the high-temperature reactions between corium and concrete.

The latest analysis was done to supercede one from May due to the emergence of some information that contradicted its predictions. Because this analysis takes into account some of this data, Tepco expect this model to be more accurate, although the company cautioned that its scenarios remain uncertain.

Unit 1 was the oldest of the three Fukushima Daiichi reactors operating at full power before the earthquake of 11 March, and was hit hardest by the loss of power following the tsunami and the flooding of diesel generators. For units 2 and 3 the analysis gave similar results to a simulation released in May, actually suggesting that the better of two scenarios presented then is more likely. Nevertheless, the cores of units 2 and 3 are thought to have overheated badly, with a large portion having melted or softened enough to slump to the bottom of the reactor vessel. A relatively small amount is thought to have passed through holes in the pressure vessel and fall to the drywell floor.

Tepco continues to inject cooling water to all three of the reactor vessels, and has succeeded in reducing temperatures from a range of sensors to well below the landmark 100ºC point usually known as cold shutdown. Official recognition of this goal in the roadmap to stabilisation, however, remains outstanding.

The extensive fuel damage means that injected water becomes highly contaminated, while holes in the pressure vessels allow this to accumulate in the building basements. Tepco operates a comprehensive set-up to treat this to a potable standard.

http://www.world-nuclear-ne..._status_3011111.html

[This message has been edited by phonedawgz (edited 12-02-2011).]

According to this image, the steel containment vessel is INSIDE the drywell. So how is it that phonedawgz article states that the fuel only made it so deep into the drywell and had not yet made it past the containment vessel steel?
Containment is in this order, reactor vessel encased in containment vessel, encased in drywell.
So it is impossible that the fuel has been eating into the concrete of the drywell, but not yet made it to the containment vessel. It appears TEPCO is lying again, and phonedawgz is pushing the lie again.

[This message has been edited by dennis_6 (edited 12-02-2011).]

Previously, the firm had said that only some of the fuel had burned through its inner pressure vessel and dropped into the containment vessel.

"Almost no fuel remains at its original position," Tepco said. The simulation shows that the fuel may have penetrated the concrete floor by up to 65cm, just 37cm from the reactor's outer steel wall.

Tepco said that about 60% of the fuel in the two other reactors that experienced meltdown had dropped onto the concrete base, but had caused less damage.
http://www.guardian.co.uk/w...ds-completely-melted

Fuel rods inside one of the reactors at the crippled Fukushima-1 NPP have probably melted down and completely destroyed the protective concrete cover, The British Guardian writes on Friday. http://english.ruvr.ru/2011/12/02/61402736.html

Wrong again dennis_6

The article isn't a story from the British Guardian. It's from "The Voice of Russia"

"The Voice of Russia" is reporting on the story the "British Guardian" wrote on the report that Tepco put out.

And guess what? They are reporting things that weren't in the Tepco report.

hmmm

For a joke - here is the Voice of Russia article in English

quote Fuel rods inside one of the reactors at the crippled Fukushima-1 NPP have probably melted down and completely destroyed the protective concrete cover, The British Guardian writes on Friday. The plant operator, Tokyo TEPCO power company, declares that this will not interfere with a cold stoppage of the reactors which may take place in the middle of December. Fuel from the reactors will be allowed to be pumped out only in 10 years, the Guardian writes. The TEPCO progress report on the accident at the NPP, which was submitted today, reads that the Fukushima-1 protective and emergency systems were not meant to withstand the force of the tsunami in March when the waves were over 15m high.

quote Originally posted by dennis_6: Fuel rods inside one of the reactors at the crippled Fukushima-1 NPP have probably melted down and completely destroyed the protective concrete cover, The British Guardian writes on Friday. http://english.ruvr.ru/2011/12/02/61402736.html

[This message has been edited by phonedawgz (edited 12-02-2011).]

quote Originally posted by phonedawgz: You so don't even have a clue about what you are talking about.

Look at the pretty picture, do you see where it points out steel containment vessel? I knew you could find it!
Do you see where it points out dry well? Good, do you see the dry well outside of the steel containment vessel?
Evidently you have no clue what you are talking about again.

quote Originally posted by dennis_6: If you were not the Baghdad Bob of the nuclear industry, maybe we could actually figure this thing out. Balance is good. Disinformation is retarded.

Then why do you continually post things that are clearly disinformation?

Wait - I just figured it out.

quote Originally posted by dratts: TEPCO, drip, drip, drip. Death by a thousand cuts. Little by little it will all come out. I don't think that it's entirely intentional. I don't think they know what they've got on their hands. I absolutely believe that they are looking for every way they can find to spin it. I don't see how they can continue to spin it. Right now there is limited access and we can't get a clear picture, so spinning will temporarily work. If it continues to work, then corruption goes farther than I know. That's when conspiracy theories hatch. When truth is buried the imagination has to take over.

Now what is it that you want to know that you think Tepco knows?

They don't know exactly what the reactors look like yet. When they produce a figure of radiation released, that figure is just an estimate. Their previous simulation showed the reactor cores melting but not melting out of the pressure vessel. With updated data their simulation shows the core melting out of the bottom of the pressure vessel.

The wackos of the left of this have been floating every wild theory their minds can come up with. Stick to the facts and we all would be much better off.