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Meltdown Likely Under Way At Japan Nuclear Reactor


george

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I'm going to sign off for a bit...

My butt's very sore, and my wife's none to happy.... :jap:

Stay out of the gay bars and tend to your wifes needs

Sorry just could not help myself. I am standing beside myself with laughter

Edited by bunta71
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Why does the densest seismic network in the world/such an earthquake prone area have Nuclear Reactors.

Of course they need the power it supplies...but still it makes one wonder.

unlimited human insanity mixed with greed and power-games is the most likely answer.

And a very good answer in a nut shell, the time is getting close for all of us to kiss our asses good-by

so earth can heal and start over.

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I'll be sure to follow Bunta's advice... :lol:

Meanwhile, while I take my break, let me leave you all with a serious question, and perhaps some of our nuclear scientist members will know the answer...

In all the hundreds of articles and such I've read on this subject lately, I haven't seen one topic addressed at all:

What exact thing does the sea water and boric acid solution do? Does it just tamp down the nuclear fire, or does it eventually extinguish it?

In other words, once they start down the sea water cooling routine, then what? Are they going to have to continue pumping an ongoing supply of new and cool sea water into Reactors 1 and 3 for ?????? how long....

When and how does it eventually end?

Even if they get regular electricity back, once they've begun the seawater approach, I don't think they can just go back to using the plant's normal cooling systems.

Edited by jfchandler
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@BreakingNews Fukushima nuclear plant was tested to withstand 7.9 quake, not 8.9 - wsj http://on.wsj.com/idd9Yo

I always though that there was a big margin (like 50% or more) built into this sort of test.

Yes, but not a 3200% margin. Magnitude scale is a logarithmic scale. Going up one point needs 32x the energy, two points 1000x

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What exact thing does the sea water and boric acid solution do? Does it just tamp down the nuclear fire, or does it eventually extinguish it?

In other words, once they start down the sea water cooling routine, then what? Are they going to have to continue pumping an ongoing supply of new and cool sea water into Reactors 1 and 3 for ?????? how long....

When and how does it eventually end?

Even if they get regular electricity back, once they've begun the seawater approach, I don't think they can just go back to using the plant's normal cooling systems.

Boric acid does basically the same thing as the control rods, absorb neutrons, stopping the reaction.

Right now none of the reactors seem to be critical (in this context read: reacting). The only thing to deal with is the rest heat. This normally takes 3 to 4 days.

Sea water is the $1 billion kill switch, those two reactors are done with. The others may be salvaged. Though after a M9.0 quake it will be a while before they pass certification again.

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Why does the densest seismic network in the world/such an earthquake prone area have Nuclear Reactors.

Of course they need the power it supplies...but still it makes one wonder.

:Thaiflag: Perhaps, you did not know....

Japan prior to the latest incidents was planning on building even larger nuclear power generator plant....

It is frightening.... how Thailand power that be and the power to be.... could so totally and absolutely influence and control

all media in Thailand.... to shut all news concerning Japan predicament on nuclear power plant explosion following the dreadful Tsunami destruction....

I never thought, Thai newsmen and Thai newswomen and Thai news organizations could be so easily influenced.... manipulated.... and controlled....

very tragic indeed.... :Thaiflag:

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Get rid of nuclear plants.

I can only compare this comment to those of tree-huggers when they yell and cry to stop pumping oil and after their protest they would go and jump into their cars/uties/whatever_else_they're_driving and take of to go home. Lead by example! Solar/wind energy is not a substitute and coal power plants create a lot more pollution and have greater effect on human health (at least those leaving nearby). Right now you are probably sitting in the cold AC room, maybe drinking cold beer, have your TV on and writing here on TV. Scrap all that, move into the jungles and live on the trees, THEN you can say let's get rid of nuke plants!

Let's try not to get polarized here. We probably have a lot we can agree upon in principle. I am a 'tree hugger' and BTW, have planted hundreds of trees up here in northern Thailand. But I conserve energy as much as reasonably (some might say 'unreasonably') possible. I don't use Air.con, not in my residences nor in my vehicles. Indeed, I have cut off the fanbelts (for AC) in my 2 cars to gain engine efficiency. I turn off all lights not actively needed. Thailand's biggest energy problem is its abject wastefulness of resources. If I was minister of Energy here, I would be the most hated person in Thailand, but I could cut energy usage by half, I jest not. Solar can work for at least a decent amount (60%?) of municipal energy supply. Open eyes, and see what's available at the cutting edge of the industry. I've also constructed several hw systems (passive solar) which are incredibly cheap, and work very well, thanks.

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As Jdietz states, Boron (Boric acid) performs as a moderator of neutrons which are responsible for the fission. The concentration is increased or decreased based on reaction requirements. Neutron moderation. The sea water is being used as it is a high volume source of coolant (AFAIK).

//edit - Boron also has a high thermal­absorption cross section and can help cool it down. Nuclear power fundamentals

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Translation from the news ticker of German-language online newspaper in Switzerland:

2011-03-13 11:25 UTC

According to a Japanese government source there is probably a core meltdown in two reactors of Fukushima plant 1. Blocks 1 and 3 are now being cooled with sea water. Plant operators are trying all means to prevent that after block 1, also bock 3 explodes. Because of defective pressure valves the technicians do not now how much water is still covering the rods. The only thing certain is that the pressure is rising.

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As Jdietz states, Boron (Boric acid) performs as a moderator of neutrons which are responsible for the fission. The concentration is increased or decreased based on reaction requirements. Neutron moderation. The sea water is being used as it is a high volume source of coolant (AFAIK).

//edit - Boron also has a high thermal­absorption cross section and can help cool it down. Nuclear power fundamentals

Just to add to this, Boron isn't normally used in BWRs (Boiling Water Reactors) in the regulation loop, as it will contaminate the environment. (Neither is sea water :) ) It is meant as a regulation agent in PWRs, which are closed-system.

But like they say, any port in a storm. Those reactors are a write-off now anyways, so just stop the reaction and cool them as efficiently as possible.

It seems like off-site (AC) power has been restored to all reactors now, so it looks like everything can be handled now if things remain stable for a day or 2 more.

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Translation from the news ticker of German-language online newspaper in Switzerland:

2011-03-13 13:32 UTC

Radiation biologist Edmund Legnfelder of the radiation institute in Munich believes that the consequences of a meltdown will be worse than 25 years ago in Chernobyl. The occurrence is different but population density is two to three times higher than in the area around the Chernobyl reactor: "I assume that it will be worse than Chernobyl" Lengfelder said to Spiegel Online.

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I'd second the request made above... If you guys want to have an energy methods and engineering expertise debate...can you please take it to another more appropriate place...

Meanwhile, speaking of meltdowns, from NHK on the Daichi No. 3 reactor:

Likely partial meltdown at second reactor

Chief Cabinet Secretary Yukio Edano says the level of coolant water at another reactor of the Fukushima No.1 [Daichi] nuclear power plant has decreased.

At 11 AM on Sunday, Edano told reporters that as the level of coolant at the Number 3 reactor of the Fukushima No.1 power plant has dropped, it is believed that part of the fuel rods became exposed.

This indicates the possibility that fuel rods at the reactor at the nuclear power plant may be melting, following a similar event at the Number 1 reactor on Saturday.

Edano said work was underway to ease pressure inside the reactor's container, and to pump water into it to raise the water level.

He said boric acid was added to the water to slow chemical reactions of the nuclear fuel.

Edano said radioactive materials were detected near the plant. He said the highest level of radiation recorded near the nuclear power station was 1,204.2 microsieverts per hour at 8:33 AM.

[That, I believe, is an even higher reading than the one from yesterday amid the problems with Reactor No. 1]

Edano said this was probably because the air inside the reactor's containment vessel is being discharged in an attempt to decrease the pressure.

Sunday, March 13, 2011 14:32 +0900 (JST)

http://www3.nhk.or.j...lish/13_22.html

That is a pretty horrendous radiation reading if taken outside the fence of the site - 1.204 mSv per hour would exceed your annual healthy dose limit within a day. I'd strongly recommend not standing at that fence on the downwind side.

For GeriatricKid who was worried about his flight plans - I shouldn't worry if I were you: You can divide the radiation you will be exposed to into three categories

Alpha particles, which can cause cancer or burns if you ingest radioactive material and it sits in your tissues for some time, but which are effectively stopped by a sheet paper; your aeroplane will not draw in so much fresh air, and any contamination will be so diluted that I would recommend you avoid the risk of ulcers from worrying about this

Beta particles: which can penetrate greater distances, but you will be pretty well shielded by the skin of the aeroplane, I believe, and similarly, any contamination drawn in through the air intakes will be so diluted as to be minimal

gamma rays: You will be exposed to a much higher gamma ray exposure from extraterrestrial sources due to reduced protection by having several kilometres less atmosphere above you; the additional gamma ray exposure from the 'radiation cloud' will not be large in comparison.

You might want to think about the gamma rays next time that you fly, though, whenever and wherever.

SC

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Translation from the news ticker of German-language online newspaper in Switzerland:

2011-03-13 13:32 UTC

Radiation biologist Edmund Legnfelder of the radiation institute in Munich believes that the consequences of a meltdown will be worse than 25 years ago in Chernobyl. The occurrence is different but population density is two to three times higher than in the area around the Chernobyl reactor: "I assume that it will be worse than Chernobyl" Lengfelder said to Spiegel Online.

I have assumed the contrary, on the grounds that at Chernobyl, there was an explosion within the reactor, and a large fraction of the core contents were vented to atmosphere, whereas I believe that the cores have remained in place in the current incident. I doubt my facile and ignorant assumptions will be repeated as news around the world, though... Of my professional reputation was at stake, I think that I would try to make a omre considered judgement, rather than an off-the-cuff assumption.

Anyway, it certainly makes you appreciate some of the safety features of the reactors in question - the secondary containment, the negative temperature coefficient of reactivity, the diverse shut-down methods... it certainly could have been a lot worse...

At hydro-electric stations, what is the normal response to a loss of containment accident?

SC

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I'd second the request made above... If you guys want to have an energy methods and engineering expertise debate...can you please take it to another more appropriate place...

Meanwhile, speaking of meltdowns, from NHK on the Daichi No. 3 reactor:

Likely partial meltdown at second reactor

Chief Cabinet Secretary Yukio Edano says the level of coolant water at another reactor of the Fukushima No.1 [Daichi] nuclear power plant has decreased.

At 11 AM on Sunday, Edano told reporters that as the level of coolant at the Number 3 reactor of the Fukushima No.1 power plant has dropped, it is believed that part of the fuel rods became exposed.

This indicates the possibility that fuel rods at the reactor at the nuclear power plant may be melting, following a similar event at the Number 1 reactor on Saturday.

Edano said work was underway to ease pressure inside the reactor's container, and to pump water into it to raise the water level.

He said boric acid was added to the water to slow chemical reactions of the nuclear fuel.

Edano said radioactive materials were detected near the plant. He said the highest level of radiation recorded near the nuclear power station was 1,204.2 microsieverts per hour at 8:33 AM.

[That, I believe, is an even higher reading than the one from yesterday amid the problems with Reactor No. 1]

Edano said this was probably because the air inside the reactor's containment vessel is being discharged in an attempt to decrease the pressure.

Sunday, March 13, 2011 14:32 +0900 (JST)

http://www3.nhk.or.j...lish/13_22.html

That is a pretty horrendous radiation reading if taken outside the fence of the site - 1.204 mSv per hour would exceed your annual healthy dose limit within a day. I'd strongly recommend not standing at that fence on the downwind side.

For GeriatricKid who was worried about his flight plans - I shouldn't worry if I were you: You can divide the radiation you will be exposed to into three categories

Alpha particles, which can cause cancer or burns if you ingest radioactive material and it sits in your tissues for some time, but which are effectively stopped by a sheet paper; your aeroplane will not draw in so much fresh air, and any contamination will be so diluted that I would recommend you avoid the risk of ulcers from worrying about this

Beta particles: which can penetrate greater distances, but you will be pretty well shielded by the skin of the aeroplane, I believe, and similarly, any contamination drawn in through the air intakes will be so diluted as to be minimal

gamma rays: You will be exposed to a much higher gamma ray exposure from extraterrestrial sources due to reduced protection by having several kilometres less atmosphere above you; the additional gamma ray exposure from the 'radiation cloud' will not be large in comparison.

You might want to think about the gamma rays next time that you fly, though, whenever and wherever.

SC

That all applies while on the plane but once disembarking may be a problem due to it being "hot" unless they take precautions and give it a significant wash down away from the point of disembarking prior..

I'm more concerned with the masses of naval and other ships off shore loaded with aid and assistance who may be in range of potential exposure if the winds blow their way, a likely scenario I'm afraid :( ..

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I find it rather curious in a country that has a wide use and long history of solar energy why this wasn't also in place as an additional back up to continue the batteries recharge of the cooling systems??

Of course better protection and preparation of the back up generators might well have averted this entire scenario..

Edited by WarpSpeed
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French urged to leave Tokyo

TOKYO -- The French Embassy is advising its citizens to leave Tokyo and its surroundings in case a cloud of radiation heads to the city.

Read more: http://www.miamihera...l#ixzz1GUIzhKcX

Oh the irony of it!

I guess they are worried that the wind might blow from Mururoa...

SC

I remember when the french pulled out of the HK Sevens because of SARS as well - luckily the mighty Nuie was able to step up to the plate (bowl, strictly speaking) and more than filled their place!

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Translation from the news ticker of German-language online newspaper in Switzerland:

2011-03-13 11:25 UTC

According to a Japanese government source there is probably a core meltdown in two reactors of Fukushima plant 1. Blocks 1 and 3 are now being cooled with sea water. Plant operators are trying all means to prevent that after block 1, also bock 3 explodes. Because of defective pressure valves the technicians do not now how much water is still covering the rods. The only thing certain is that the pressure is rising.

Yikes...that's not the news I was hoping to hear upon my return home...

Admittedly, it's attributed to a "source" and it's not even from one of the main Japanese media, whom you might assume would have the best contacts in such a situation..

Nonetheless, it's worrisome... If (if if if if....) that is in fact happening, it would be Three Mile Island all over again....

Plus, I really begin to worry when the French start calling "retreat" from Tokyo.... :whistling:

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I'd second the request made above... If you guys want to have an energy methods and engineering expertise debate...can you please take it to another more appropriate place...

Meanwhile, speaking of meltdowns, from NHK on the Daichi No. 3 reactor:

Likely partial meltdown at second reactor

Chief Cabinet Secretary Yukio Edano says the level of coolant water at another reactor of the Fukushima No.1 [Daichi] nuclear power plant has decreased.

At 11 AM on Sunday, Edano told reporters that as the level of coolant at the Number 3 reactor of the Fukushima No.1 power plant has dropped, it is believed that part of the fuel rods became exposed.

This indicates the possibility that fuel rods at the reactor at the nuclear power plant may be melting, following a similar event at the Number 1 reactor on Saturday.

Edano said work was underway to ease pressure inside the reactor's container, and to pump water into it to raise the water level.

He said boric acid was added to the water to slow chemical reactions of the nuclear fuel.

Edano said radioactive materials were detected near the plant. He said the highest level of radiation recorded near the nuclear power station was 1,204.2 microsieverts per hour at 8:33 AM.

[That, I believe, is an even higher reading than the one from yesterday amid the problems with Reactor No. 1]

Edano said this was probably because the air inside the reactor's containment vessel is being discharged in an attempt to decrease the pressure.

Sunday, March 13, 2011 14:32 +0900 (JST)

http://www3.nhk.or.j...lish/13_22.html

That is a pretty horrendous radiation reading if taken outside the fence of the site - 1.204 mSv per hour would exceed your annual healthy dose limit within a day. I'd strongly recommend not standing at that fence on the downwind side.

For GeriatricKid who was worried about his flight plans - I shouldn't worry if I were you: You can divide the radiation you will be exposed to into three categories

Alpha particles, which can cause cancer or burns if you ingest radioactive material and it sits in your tissues for some time, but which are effectively stopped by a sheet paper; your aeroplane will not draw in so much fresh air, and any contamination will be so diluted that I would recommend you avoid the risk of ulcers from worrying about this

Beta particles: which can penetrate greater distances, but you will be pretty well shielded by the skin of the aeroplane, I believe, and similarly, any contamination drawn in through the air intakes will be so diluted as to be minimal

gamma rays: You will be exposed to a much higher gamma ray exposure from extraterrestrial sources due to reduced protection by having several kilometres less atmosphere above you; the additional gamma ray exposure from the 'radiation cloud' will not be large in comparison.

You might want to think about the gamma rays next time that you fly, though, whenever and wherever.

SC

That all applies while on the plane but once disembarking may be a problem due to it being "hot" unless they take precautions and give it a significant wash down away from the point of disembarking prior..

I'm more concerned with the masses of naval and other ships off shore loaded with aid and assistance who may be in range of potential exposure if the winds blow their way, a likely scenario I'm afraid :( ..

I'd recommend against licking the outside of the aeroplane...

Unlike Chernobyl, as I mentioned in the other post, I understand that the reactor core has largely remained intact (albeit damaged) and while the primary containment (the cladding on the fuel pins) may have failed, there has not been any catastrophic event to actually eject core material.

How do they dispose of the low level radioactive waste from coal-fired power stations, by the way?

My understanding is that most of it is diluted into the atmosphere or tipped into surface landfill / lagoons - or made into construction products

SC

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Translation from the news ticker of German-language online newspaper in Switzerland:

2011-03-13 14:40 UTC

Japanese authorities have declared a nuclear emergency in one more nuclear plant. Because of excessive radiation values the lowest emergency level has been declared for the Onagawa plant, the International Atomic Energy Agency (IAEA) communicated in Vienna on Sunday.

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