Meltdown Likely Under Way At Japan Nuclear Reactor

[atsiii]

http://www.nytimes.com/cwire/2011/03/25/25climatewire-us-experts-blame-fukushima-1-explosions-and-19903.html?pagewanted=2

The above is a good article... some excerpts follow:

In an analysis shared with other U.S. nuclear experts Saturday, Lake Barrett, who led the Nuclear Regulatory Commission's investigation of the Three Mile Island accident, describes the burning of zirconium cladding on fuel rods in the reactor cores after normal cooling operations failed because of a lack of electric power. A perilous buildup of hydrogen and steam followed within the concrete primary containment shell surrounding the reactor pressure vessel in units 1 and 3, and then in 2.

"To prevent a catastrophic primary containment system failure the operators vented the primary containment through the safety venting system trying to reject heat and excess gases up the 100 meter tall stacks at the plants," he wrote. "Normally there are operable fans and filters to control this dangerous mixture, but there was no electrical power for the fans. So most, if not all, of this dangerous mix of hydrogen gas seeped into the reactor building in Units 1 and 3. The hydrogen, being lighter than air, mixed with air in the upper large refueling floor area."

Some source ignited the explosive mixture, blasting away the sheet metal roofs and sides of the top section of the outer secondary containment building in units 1 and 3, he said. Braving dangerous conditions, workers had time to remove a wall panel at the top of the unit 2 reactor building providing an exit for hydrogen, avoiding a similar roof-level explosion, he said. The damage to the buildings 1 and 3 and the opening in 2 created an exit route for radioactive releases from the spent fuel pools at the top of the reactor pools.

Another former senior NRC official, speaking on background, said he believed -- based on the still incomplete evidence from Fukushima -- that hydrogen was vented from the primary containment through duct work that allowed the hydrogen to collect in units 1 and 3 in the refueling floor in the secondary containment building. Normally, an exhaust system could have filtered and removed the hydrogen, but it was not working because of the loss of outside electric power. When the hydrogen accumulated above the 8 percent detonation limit in air in units 1 and 3, it exploded.

The focus on operators' actions during the peak of the crisis to relieve high pressures inside the containment structures points toward one of the central unanswered question in the accident: How did hydrogen escape from the venting system into the top area of the reactor buildings?

Bill Borchardt, NRC executive director for operations, was asked at an NRC meeting Monday whether the Fukushima Mark I units had hardened venting systems. "That we're not clear on. I'm not sure. I can't really answer that question."

David Lochbaum, chief nuclear safety official of the Union of Concerned Scientists, has another possible explanation. As steam and hydrogen built up within the primary containment shell, high pressure may have forced an opening between the primary containment shell, called the drywell, and the metal cap that is bolted onto the shell. A pressure test decades ago at the Brunswick Nuclear Plant in North Carolina demonstrated that such a high-pressure leak could occur in Mark I reactors built at the Fukushima plant, Lochbaum said.

"This tragedy will be closely examined for its causes, what happened and why," Lochbaum said. "That scrutiny must determine how hydrogen got into the reactor buildings to cause the catastrophic explosions. The drywell head pathway may be that answer. We need to stress that we're not putting this forward as the only answer for this question, but it's the most plausible explanation that we've heard to date."

[harrycallahan]

What a load of rubbish. I find jfchandlers posts are what I look for in this thread.

Perhaps people could prune the huge quotes they include with their one line comments...

that would tidy the thread.

Pete in NZ

Why don't you just open this URL which is the orignal source for 90 % of it?

http://www3.nhk.or.jp/daily/english/

If you want to discuss a particular quote you quote that, otherwise the article in it's entirety doesn't need to be dumped. There are copyright issues too with posting whole articles.

I find it hard to believe anyone would prefer to source their news from this thread instead of....

[powderpuff]

would someone tell me about the safety of nuclear power... oh and the wisdom behind building a reactor in a known earthquake area?

By the same logic why would you build a 100 storey skyscraper in a known earthquake prone area?

Answer? You use engineering principles to prepare the foundation. It wasn't so much the earrthquake that caused this disaster but 10-15 meter high ocean waves.

That was a failure of the design engineers to anticipate maximum wave height faced by the structure.

Nuclear energy can be made safe by design engineering, this design was obsoleted in 1972.

Human failure.

5 billion people on the planet. They need energy. Where is it gonna come from?

[atsiii]

would someone tell me about the safety of nuclear power... oh and the wisdom behind building a reactor in a known earthquake area?

By the same logic why would you build a 100 storey skyscraper in a known earthquake prone area?

Answer? You use engineering principles to prepare the foundation. It wasn't so much the earrthquake that caused this disaster but 10-15 meter high ocean waves.

That was a failure of the design engineers to anticipate maximum wave height faced by the structure.

Nuclear energy can be made safe by design engineering, this design was obsoleted in 1972.

Human failure.

5 billion people on the planet. They need energy. Where is it gonna come from?

I must respectfully disagree. Engineers do not yet know to what extent (if any) the reactors were damaged by the earthquake, and thus it is premature to say they either did or did not withstand the quake. We know the quake knocked the plants off the grid, and it may or may not have damaged cooling pipes, pumps, etc. We know the tsunami wiped out the backup power systems, and we know the tertiary power supply (batteries) were of insufficient design life. Depending on radiation levels, it will be a long time before engineers can analyze and quantify the actual quake and tsunami damage, and thus whether or not structural design standards are adequate. The arguments over whether or not safety standards are adequate will be much more wide-ranging.

One problem that will be studied and argued is that plant designs typically evaluate the risk/benefit of natural disasters in isolation. This accident demonstrates that multiple disasters can and do occur simultaneously. Consider what might happen right now if a third disaster befell the struggling plant--say a massive natural gas spawned fire that again took the plants off the grid, wiped out and melted equipment, power generators, etc.?

Finally, even with all the best engineering, you don't build 100 story skyscrapers in an active earthquake zone. The highest building in Tokyo is 60 stories, with only 15 buildings between 50 and 60 floors high. Until 1963 the heigth limit was 31 meters, which is why the vast majority of buildings in Tokyo are 5 to 8 stories, max.

Edited March 26, 2011 by atsiii

[elcent]

High level of iodine 131 in seawater near N-plant

A high level of radioactive iodine has been detected in seawater near Japan's troubled Fukushima Daiichi nuclear power plant. The facility was hit by the March 11th earthquake and tsunami.

The Nuclear and Industrial Safety Agency said on Saturday that iodine 131 in excess of 1,250 times regulated standards was found in seawater collected 330 meters south of a plant water outlet at 8:30 AM on Friday.

The agency says there is no immediate threat to people within the 20-kilometer evacuation zone. The agency adds that as seawater is dispersed by ocean currents the contamination level will decline.

Iodine 131 at146.9 times regulated standards was detected in seawater in the area on Wednesday.

Saturday, March 26, 2011 12:44 +0900 (JST)

http://www3.nhk.or.jp/daily/english/26_13.html

[Chopperboy]

CHINA DAILY Mar 26

SHANGHAI/Xiamen, Fujian — Two Japanese travelers had "alarmingly high levels of radiation" when they arrived in East China's Wuxi city, China's quality watchdog reported on Friday.

The high levels were discovered when the two arrived from Tokyo on Wednesday, said the General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ).

The regulator also said that "abnormal" levels of radiation had been found on Monday on a Japanese merchant vessel berthed in East China's Xiamen port, Fujian province.

The detections were the latest consequences of contamination from a crippled nuclear plant following the Asian nation's devastating earthquake and ensuing tsunami two weeks ago.

The agency said the radiation was discovered on the two Japanese nationals when the local quality control bureau conducted radiation checks on passengers aboard flight ZH9056 that reached Wuxi, East China's Jiangsu province, from Tokyo on Wednesday.

[powderpuff]

In the United States the big news is that the containment is breached.

I personally don't know if this is true or not.

[elcent]

In the United States the big news is that the containment is breached.

I personally don't know if this is true or not.

The Japanese PM apoligized yesterday for the "worst case scenario" already. - precautional excuses - or for real needs to be confirmed.

[Chopperboy]

The world may soon get a glimpse inside Japan's stricken Fukushima nuclear plant -- through the "eyes" of a U.S.-made robot.

A Massachusetts company that manufactures robots for U.S. military bomb disposal units in Iraq and Afghanistan has sent four of its top-technology robots to Japan, to venture into radiation-exposed areas where it's too dangerous for humans to go. The machines take measurements and record real-time color video, then transmit it back to engineers in the safety zone. The deployment of mechanical helpers like those from iRobot could lessen the safety risks to the plant's human staffers.

Trainer said he doesn't know exactly when his company's robots will enter the Fukushima Dai-ichi nuclear plant, or even whether they may have done so already. The equipment has never been exposed to such high levels of radioactive material.

"Certainly, radiation will have some impact on the circuits. ... Some of this will be understanding what it might be like to operate in such conditions," Trainer said. "To be quite honest with you, some of this will be experimentation."

After a 1999 accident at Japan's Tokaimura nuclear facility, the Japanese government enlisted local companies like Hitachi, Mitsubishi and Toshiba to built prototype robots, including one radiation-proof model - but the robots sold poorly.

http://www.aolnews.com/2011/03/24/us-robots-to-peek-inside-japans-nuclear-meltdown/

Edited March 26, 2011 by Chopperboy

[JetsetBkk]

What a load of rubbish. I find jfchandlers posts are what I look for in this thread.

Perhaps people could prune the huge quotes they include with their one line comments...

that would tidy the thread.

Pete in NZ

Why don't you just open this URL which is the orignal source for 90 % of it?

http://www3.nhk.or.jp/daily/english/

If you want to discuss a particular quote you quote that, otherwise the article in it's entirety doesn't need to be dumped. There are copyright issues too with posting whole articles.

I find it hard to believe anyone would prefer to source their news from this thread instead of....

Thanks, Harry - you made my day.

But I'm afraid it's too late. It appears to have become a competition now for most posters to find something - ANYthing - that has not been reported already and copy/paste the whole story into this thread. Ah well, we tried.

[Jai Dee]

A number of off-topic posts have been deleted from this thread.

[Chopperboy]

Expert: ‘Breach of containment’ scariest words for scientists

Michio Kaku’s comments came after news that Japanese nuclear experts said they suspect there has been a possible breach at the Fukushima Dai-ichi nuclear complex.

“This is huge. For the first time, they’re using that dreaded word, ‘breach,’ Kaku said during an interview at KATU’s studios. “Plutonium is the most toxic chemical known to science. A speck of plutonium, a millionth of a gram, could cause cancer.”

Still, Kaku said he worries the recent reported breach could force workers to evacuate. If that happens firefighters would stop spraying water on the core reactor. He said the meltdown that would follow would likely reach the West Coast.

“Once they evacuate, then we pass the point of no return and meltdowns are inevitable at three reactor sites leading to a tragedy far beyond that of Chernobyl, creating permanent dead zones in Japan,” he said.

http://www.katu.com/news/local/118692859.html

[canuckamuck]

Kaku is a glass half empty kind of guy isn't he

[brahmburgers]

5 billion people on the planet. They need energy. Where is it gonna come from?

The sun, wind, water, geothermal, jetstream winds, tides, ......but most important factor in the energy equation: CONSERVATION.

Nuclear is fraught with more problems than a balloon woven with human hair in a firestorm.

[atsiii]

http://www.reuters.com/article/2011/03/26/japan-reactors-risks-idUSL3E7EQ03V20110326

"In recent days fears have grown that the core of one of the reactors, No.3, had been damaged by the quake and tsunami and was leaking radiation."

As I said in a previous post, the jury is still out as to whether the physical integrity of the reactors themselves were compromised by the quake and/or tsunami. Thus, it's impossible to determine at this stage whether or not the plant's design guidelines were adequate. A lot of metallurgical forensics will be required to determine the cause of various failures... if and when we can get close enough.

"Officials have cited other possible sources of the unusually high radiation in the standing water, such as steam-venting operations or water leakage from pipes or valves."

"The No. 2 reactor's primary containment vessel, designed to prevent radiation leaks, may have been damaged when there was an explosion in the building on March 15. The portion of the vessel damaged was the suppression pool, into which steam is vented from the reactor to relieve pressure. The IAEA said the blast "may have affected the integrity of its primary containment vessel".

The hits just keep on coming!! Because #4's core had been emptied into the cooling pool, I read the other day that pool contains +/- 98 tons (548 rods) of "un-spent" fuel, and it too may have some structural problems. Keep your fingers crossed... if things are getting better, it's not at a very fast pace.

[Organicpete]

I find it hard to believe anyone would prefer to source their news from this thread instead of....

Whys that ?

I found this thread at the start of the nuclear disaster when there was precious little news.

I return as it seems to be a useful collection of up to date links ( and text )

and possibly more informed discussion.

That NHK is fine if you like reading little scroll boxs

Pete

[Organicpete]

5 billion people on the planet. They need energy. Where is it gonna come from?

The sun, wind, water, geothermal, jetstream winds, tides, ......but most important factor in the energy equation: CONSERVATION.

Nuclear is fraught with more problems than a balloon woven with human hair in a firestorm.

Well put.

Conservation will never be as sexy

as some magic bullet technology but we had better wake up to it

Pete

Edited March 26, 2011 by Organicpete

[unblocktheplanet]

Wow, brahm, you've added poetry to this thread: "balloon woven of human hair in a firestorm" - whew! First thing made me smile in this forum!

We've not been told if the US robots are radiation-proof. In particular, wouldn't radiation cloud pix and video? Or am I thinking of old-school tech?

[atsiii]

Wow, brahm, you've added poetry to this thread: "balloon woven of human hair in a firestorm" - whew! First thing made me smile in this forum!

We've not been told if the US robots are radiation-proof. In particular, wouldn't radiation cloud pix and video? Or am I thinking of old-school tech?

I remember they were using robots with cameras at TMI...

[elcent]

Expert: 'Breach of containment' scariest words for scientists

Michio Kaku's comments came after news that Japanese nuclear experts said they suspect there has been a possible breach at the Fukushima Dai-ichi nuclear complex.

"This is huge. For the first time, they're using that dreaded word, 'breach,' Kaku said during an interview at KATU's studios. "Plutonium is the most toxic chemical known to science. A speck of plutonium, a millionth of a gram, could cause cancer."

Still, Kaku said he worries the recent reported breach could force workers to evacuate. If that happens firefighters would stop spraying water on the core reactor. He said the meltdown that would follow would likely reach the West Coast.

"Once they evacuate, then we pass the point of no return and meltdowns are inevitable at three reactor sites leading to a tragedy far beyond that of Chernobyl, creating permanent dead zones in Japan," he said.

http://www.katu.com/.../118692859.html

... thanks for that link. Scarry indead, but not unexpected for some.

Even The Nation has found something

Eight radioactive substances found in water at plant

Tokyo - Japanese nuclear authorities have identified eight radioactive substances in stagnant water in the basement of part of the Fukushima nuclear power plant, an analysis released Saturday by the Nuclear and Industrial Safety Agency showed.

The highest levels found in the water in block 1 of the plant were of caesium 137, a radioactive isotope that was released into the environment in the Chernobyl disaster. It appeared at levels of 1.8 million becquerel.

Caesium 137, in contrast to radioactive iodine, has a relatively long half life of 30.2 years. It is created during nuclear fission.

The water also contained Caesium isotopes 134 and 136 as well as iodine-131.

The plant operator, Tokyo Electric Power Co (TEPCO), has vowed to clear the water as quickly as possible to allow workers to continue efforts to cool the reactors.

Three workers, who were working to restore cooling functions at reactor 3, were exposed radiation levels in water that was 10,000 times the normal level, Tokyo Electric Power Co (TEPCO), the plant's operator, said Friday.

Those levels suggested the vessel might have been damaged and leaked radioactive materials, Nishiyama told a news conference.

Seventeen workers at the plant have been contaminated since the plant was damaged in a March 11 earthquake and resulting tsunami, Kyodo news agency reported Saturday. That figure includes only those who have been exposed to more than 100 millisieverts of radiation, the maximum exposure for a nuclear plant worker for an entire year. //DPA

Thanks to the DPA (German Press Agency) Edited March 26, 2011 by elcent

[elcent]

Wow, brahm, you've added poetry to this thread: "balloon woven of human hair in a firestorm" - whew! First thing made me smile in this forum!

We've not been told if the US robots are radiation-proof. In particular, wouldn't radiation cloud pix and video? Or am I thinking of old-school tech?

I remember they were using robots with cameras at TMI...

You can be sure that they had a clearer pictures than they always admitted. Now it's maybe too late.

[brahmburgers]

Wow, brahm, you've added poetry to this thread: "balloon woven of human hair in a firestorm" - whew! First thing made me smile in this forum!

We've not been told if the US robots are radiation-proof. In particular, wouldn't radiation cloud pix and video? Or am I thinking of old-school tech?

I remember they were using robots with cameras at TMI...

They got millions of too-cute robot dogs in Japan. Simple, just strap a camcorder on it, and, ....on 2nd thought, it would be a blob of steaming plastic with wire sticking out - in about 3 minutes.

[elcent]

hundreds of thousands of demostrators demand the closure of nuclear power plants. This is just the beginning. http://www.spiegel.de/politik/deutschland/0,1518,753341,00.html (in German, with images though)

[James3212]

An interesting thing from 2008 on how to store the solar power in houses as an alternative to batteries

http://web.mit.edu/newsoffice/2008/oxygen-0731.html

Hopefully it develops to be good enough soon... Sorry for the off topic, you can delete if its not that relevant to this...

Edited March 26, 2011 by James3212

[JetsetBkk]

Fukushima scaremongers becoming increasingly desperate

Dead horse long ago flogged down to a mere red stain

The situation at the quake- and tsunami-stricken Fukushima Daiichi nuclear powerplant in Japan was brought under control days ago. It remains the case as this is written that there have been no measurable radiological health consequences among workers at the plant or anybody else, and all indications are that this will remain the case. And yet media outlets around the world continue with desperate, increasingly hysterical and unscrupulous attempts to frame the situation as a crisis.

From here: http://www.theregister.co.uk/2011/03/25/fukushima_scaremongering_debunk/

Read it if you dare!

And there's more...

Tokyo tapwater - THE NEW GROUND ZERO!!! Fallout!!! Chernobyl!!!

Then there's the matter of the tapwater in Tokyo. Two days ago, levels of radioactive iodine-131 were found in the city's water which were above the safety limit for baby milk calculated on the basis of a year's consumption: in other words, if babies drank such water for a year constantly they would have a tiny, minuscule extra risk of thyroid cancer.

One should note that iodine-131 has a half-life of 8 days: it disappears almost completely within a matter of weeks. The Fukushima reactors have not been generating any more of it since they scrammed nearly a fortnight ago, and the residual core heating which is causing it to be emitted has plunged to tiny proportions of that seen in the days after the quake.

From here: http://www.theregister.co.uk/2011/03/25/fukushima_scaremongering_debunk/page2.html

These reports are brought to you in the probably hopeless attempt to counter the incessant postings of the doom-sayers in this forum.

Have a nice, radiation-free day.

Edited March 26, 2011 by JetsetBkk

[Lopburi99]

If I may ask, JetsetBkk, with respect to which specific issues (other than tapwater) do you feel they are being unduly pessimistic?

Edited March 26, 2011 by Lopburi99

[Hawaiian]

Now freshwater is being barged in by sea to be used for cooling instead of salt water. Hope that works better than the corrosive seawater which some believe is making a bad situation worse.

Although the Sendai area is rarely affected by typhoons, that is something that needs to be addressed. Stormy weather offshore could seriously affect the ability to deliver supplies by sea. Typhoon season is just around the corner!

Edited March 26, 2011 by Hawaiian

[Lite Beer]

Japan Nuclear Agency: Radioactivity in sea water off Fukushima plant is up to 1,850 times the usual level./RT@SkyNewsBreak

[Lite Beer]

Japanese nuclear plant awaits freshwater to cool reactors - Fukushima crisis will take "a long time" to resolve: http://t.co/F2cCeSp/RT@markmackinnon

[elcent]

Fukushima scaremongers becoming increasingly desperate

Dead horse long ago flogged down to a mere red stain

The situation at the quake- and tsunami-stricken Fukushima Daiichi nuclear powerplant in Japan was brought under control days ago. It remains the case as this is written that there have been no measurable radiological health consequences among workers at the plant or anybody else, and all indications are that this will remain the case. And yet media outlets around the world continue with desperate, increasingly hysterical and unscrupulous attempts to frame the situation as a crisis.

From here: http://www.theregist...ngering_debunk/

Read it if you dare!

And there's more...

Tokyo tapwater - THE NEW GROUND ZERO!!! Fallout!!! Chernobyl!!!

Then there's the matter of the tapwater in Tokyo. Two days ago, levels of radioactive iodine-131 were found in the city's water which were above the safety limit for baby milk calculated on the basis of a year's consumption: in other words, if babies drank such water for a year constantly they would have a tiny, minuscule extra risk of thyroid cancer.

One should note that iodine-131 has a half-life of 8 days: it disappears almost completely within a matter of weeks. The Fukushima reactors have not been generating any more of it since they scrammed nearly a fortnight ago, and the residual core heating which is causing it to be emitted has plunged to tiny proportions of that seen in the days after the quake.

From here: http://www.theregist...bunk/page2.html

These reports are brought to you in the probably hopeless attempt to counter the incessant postings of the doom-sayers in this forum.

Have a nice, radiation-free day.

I read it both. I must say the writer doesn't know anything. Almost a platonic character. No reality, no investigations of whatsoever sorts.Parroting from here and there, putting the issues out of context and presenting it, that is.

It's far from over. The messages of a stabilized situation means that the crisis is stable which is itself a catastrophy.

I'd suggest that these kind of people shoud go there and then tell us again. It would be different.

Any and all nuclear power plants have a kind of higher wobbling radiation arround the reactor buildings at any time given. There's a beast inside, manmade, that wants to unleash it's destructive powers. Don't blame the beast but those that feed it.

I accomplished the daily dose of fear-mongering for today . And to the sooth sayers, don't dare to check with reality, you're going to fall in deep depressions.