Meltdown Likely Under Way At Japan Nuclear Reactor

[jfchandler]

One of the prior posts from a German newspaper made reference to the presence of plutonium as a fuel in Daichi Reactor No. 3... The original reference didn't mean anything to me... But now I see it's surfaced in part of a Reuters report tonight...

The No. 3 reactor uses a mixed-oxide fuel which contains plutonium, but plant operator Tokyo Electric Power Co (TEPCO) said it did not present unusual problems.

So I'm presuming that's different from what's present in Reactor No. 1???

[jsflynn603]

Reply to post in other thread:

Thanks, I understand this point of view, but cooling it with sea-water would have the same effect as boric acid. - The reactor would never be up again. This is talked about since more than 12 hours.

The problems seem to be with the injection of sea-water and boric acid.

Although Boric acid isn't a standard regulating compound in a BWR, it is just an additive to the coolant, and does no harm to the reactor. It regulates the reaction in much the same way as the control rods do. When flushed out again, reaction starts back up.

The boron in boric acid is a neutron modulator also known as a neutron absorber.

The core reaction produces neutrons, the neutrons hit another element and can release two neutrons which hit another element each releasing two neutrons...thus increasing core reaction and of course, heat. So the use of boric acid is an attempt to quench the ongoing nuclear reaction as well as cool the core. Sea water will cool the core but absent the boron modulater, will not act to slow the nuclear reaction.

That boric acid was used is another bit of evidence that at least part of the core (fuel rods) have melted. The problem is that once part melts, if the melted portions flow together (at about 5080 Fahrenheit) neutron flux increases, the reaction increases, and heat increases. If enough of the uranium/ceramic pellets melt and flow the molten mass can become critical. This would likely result in a physical explosion, not a thermonuclear explosion but would be catastrophic. This was the great fear at Chernobyl and luckily though the core melted, the molten mass never managed to come together in a critical mass and enough neutron absorbing material was piled on it to slow the reaction.

There is a bogus radiation map circulating, purportedly from the Australian government predicting deadly radiation exposure--it is BOGUS, don't believe a bit of it.

Still, the absence of quality reporting on the incident is quite worrisome to me.

[jfchandler]

while this is true, there are a number of slightly worrying observations:

- During these 3 to 4 days (and up to a week or so) there need to be water cooling as well

- The fact that they are adding Boron to the water may point to the fact that the reaction is ongoing / maybe the control rods haven't been fully inserted due to warping of the structure by the quake

- They can't confirm on their instruments that the water they are pumping in is actually raising the level in the reactor. Not sure at this time if it is an instrument failure or something else. I don't think they are willing to go in and have a look...

Indeed, there were reports today the rods in Daichi Reactor No. 3 were uncovered by an amount of two meters... And I asked at the time, how can that be when they've been pumping in sea water all day...

Yet somehow, they're apparently able to tell to what extent the reactor cores are not covered by coolant... It's confusing...

[jfchandler]

If enough of the uranium/ceramic pellets melt and flow the molten mass can become critical. This would likely result in a physical explosion, not a thermonuclear explosion but would be catastrophic.

Thanks for the scientific explanation... That, I guess, is the worst case scenario to fear... Keep that sea water pumping...

[jfchandler]

And yet more reactors in trouble:

Reuters - The Japan Atomic Power Co. says the cooling process is working at its Tokai No. 2 Nuclear Power Plant.

And an earlier Reuters post on this:

(Reuters) - The cooling system pump has stopped at the Tokai No.2 nuclear power plant in Japan's Ibaraki prefecture, Kyodo news reported, in the wake of the massive earthquake that has crippled other reactors in the country. The plant, located about 120 km (75 miles) north of Tokyo, had suffered a nuclear accident in 1999.

Edited March 13, 2011 by jfchandler

[elcent]

URGENT: Cooling system pump stops at Tokai nuclear power plant: fire dep't

TOKYO, March 14, Kyodo

The Fire and Disaster Management Agency said a cooling system pump stopped operating at Tokai No. 2 Power Station, a nuclear power plant, in the village of Tokai, Ibaraki Prefecture..

http://english.kyodonews.jp/news/2011/03/77481.html

Then there's an issue about Unit three which is in troubles too. this reactor runs also with 5 - 10% putonium which makes it the most dangerous reactor when an explosion happens. Two microgram kill a human body. Alltogether there are aboutr 100 tons of Uranium in each of the reactors.

Let's hope and pray that it doesn't happen.

Further evacuation are discussed but not planned yet.

And then there's the outbreak of the Vulcano in the South which was likely triggered by the strong quake. Germans scientists haverecently proven that strong Earthquakes can trigger vulcanos.

Must be like Armageddon for the people there.

What can individuals do to help?

[jfchandler]

Japan nuclear health risks low, won't blow abroad

By Alister Doyle, Environment Correspondent

Sun Mar 13, 2011 12:36pm EDT

OSLO (Reuters) - Health risks from Japan's quake-hit nuclear power reactors seem fairly low and winds are likely to carry any contamination out to the Pacific without threatening other nations, experts say.

Tokyo battled to avert a meltdown at three stricken reactors at the Fukushima plant in the worst nuclear accident since the 1986 Chernobyl disaster, triggered by Friday's tsunami. Radiation levels were also up at the Onagawa atomic plant.

"This is not a serious public health issue at the moment," Malcolm Crick, Secretary of the U.N. Scientific Committee on the Effects of Atomic Radiation, told Reuters.

"It won't be anything like Chernobyl. There the reactor was operating at full power when it exploded and it had no containment," he said. As a precaution, around 140,000 people have been evacuated from the area.

MORE: http://www.reuters.com/article/2011/03/13/us-japan-quake-health-idUSTRE72C2OS20110313

[harrycallahan]

Must be like Armageddon for the people there.

What can individuals do to help?

Maybe stop the fear mongering?

[elcent]

while this is true, there are a number of slightly worrying observations:

- During these 3 to 4 days (and up to a week or so) there need to be water cooling as well

- The fact that they are adding Boron to the water may point to the fact that the reaction is ongoing / maybe the control rods haven't been fully inserted due to warping of the structure by the quake

- They can't confirm on their instruments that the water they are pumping in is actually raising the level in the reactor. Not sure at this time if it is an instrument failure or something else. I don't think they are willing to go in and have a look...

Indeed, there were reports today the rods in Daichi Reactor No. 3 were uncovered by an amount of two meters... And I asked at the time, how can that be when they've been pumping in sea water all day...

Yet somehow, they're apparently able to tell to what extent the reactor cores are not covered by coolant... It's confusing...

I think the pumping of water goes on a very slow pace. The reason might be that they have to release the pressure and heat in order to be able to pump water into the reactors. This could go on for quite a while.

[elcent]

Must be like Armageddon for the people there.

What can individuals do to help?

Maybe stop the fear mongering?

Fear mongering?

After an earthquake with the strength of nine on the Richter-scale, a devastating tsunami that killed 10s of thousands of people, a volcano outbreak and the reactor catastrophies do you think it is suitable to say everything is alright?

Still there's is huge danger coming from one of the reactors that runs additionally with plutonium.

I think it's better to call a spade a spade.

[balo]

This is like a bad dream I just wanna wake up .from

[jfchandler]

And now we turn to Fukushima Daichi Reactor 2 (as opposed to No's 1 and 3):

TEPCO is preparing to put sea water into the No.2 reactor at its Fukushima Daiichi nuclear power plant, Jiji news agency says. TEPCO, Japan's largest electric utility, is already injecting sea water into the No.1 and No.3 units at the plant to cool them down and reduce pressure inside reactor container vessels.

Meanwhile, a Reuters bulletin board poster had this comment on the plutonium fuel in the Reactor No. 3...

The MOX fuel in unit 3 can fail more easily when heated up because the melting point is lower and there is more gas buildup with the fuel elements. There is much less experimental data and practical experience of the behavior of MOX fuel under accident conditions compared with conventional uranium fuel.

Anyone knowledgeable on this point???

[elcent]

impressing before and after images at NYT. The slide probably won't work with some IE browsers though.

http://www.nytimes.com/interactive/2011/03/13/world/asia/satellite-photos-japan-before-and-after-tsunami.html

[jfchandler]

A recap from Kyodo News on the Tokai reactor cooling problems:

One of the two cooling system pumps at the Tokai No. 2 nuclear power plant in the village of Tokai, Ibaraki Prefecture, stopped Friday when a massive earthquake hit Japan but there is no problem with cooling as the remaining pump is working, according to local authorities late Sunday. Tokai No. 2 Power Station, operated by Japan Atomic Power Co., shut down automatically after the magnitude 9.0 quake, one of the biggest quakes in history, jolted northeastern and eastern Japan.

According to a report submitted to the Ibaraki prefectural government, one of the two pumps used to cool the water of a suppression pool for the nuclear reactor at the plant stopped working.

The nuclear safety section of the prefectural government said the other pump is working and that there is no problem with cooling the reactor. All control rods are set in completely at the nuclear reactor, it said.

Japan Atomic Power said the reactor core has been cooled without any problem.

http://english.kyodonews.jp/news/2011/03/77484.html

[elcent]

And now we turn to Fukushima Daichi Reactor 2 (as opposed to No's 1 and 3):

TEPCO is preparing to put sea water into the No.2 reactor at its Fukushima Daiichi nuclear power plant, Jiji news agency says. TEPCO, Japan's largest electric utility, is already injecting sea water into the No.1 and No.3 units at the plant to cool them down and reduce pressure inside reactor container vessels.

Meanwhile, a Reuters bulletin board poster had this comment on the plutonium fuel in the Reactor No. 3...

The MOX fuel in unit 3 can fail more easily when heated up because the melting point is lower and there is more gas buildup with the fuel elements. There is much less experimental data and practical experience of the behavior of MOX fuel under accident conditions compared with conventional uranium fuel.

Anyone knowledgeable on this point???

MOX stands for Uranium and Plutonium mixture and was introduced I think it was last year.

Once the rods are melting and when any of the radioactivity goes into the atmosphere or ground water the area is doomed.

This plutonium used is a result and kind of recycling of the Uranium rods.

[jfchandler]

And more from Kyodo News on Daichi Reactor No. 3 and its plutonium fuel:

An official of the government's Nuclear and Industrial Safety Agency said half of the roughly 4-meter rods were still exposed late Sunday, but that seawater kept being pumped into the reactor vessel. The procedure temporarily exposed the top parts of MOX fuel rods above coolant water by nearly 3 meters. MOX fuel refers to plutonium-uranium mixed oxide fuel, used for so-called ''pluthermal'' power generation.

Radiation around the reactor rose three times the benchmark limit to 1,557 micro sievert per hour at 1:52 p.m. Sunday, but the figure went down to 184 about 50 minutes later. Given the radiation level, Edano said a hydrogen explosion is unlikely to affect human health even if one occurred.

The No. 3 reactor was the sixth reactor overall at the Fukushima No. 1 [Daichi] and [Daini] No. 2 plants, which are located about 11 km apart, to experience cooling failure since the massive earthquake and ensuing tsunami struck the power facilities.

Jfchandler Note - the 1,57 mSv figure mentioned above is the highest radiation reading I've seen yet publicly disclosed at Fukushima....

[elcent]

[elcent]

any serious meltdown would result in a worse situation than Tschenobil due to the higher tensity of population alone.

[jfchandler]

Sunday night update from NHK, basically confirming what we reported above from Kyodo News:

Cooling system problems continue to plague two nuclear plants in earthquake-hit Fukushima Prefecture.

The level of coolant water in the Number Three reactor at the Fukushima Number One power plant dropped on Sunday, leaving the fuel rods exposed by two meters. The situation continued for at least until 3pm, possibly causing a partial melting of the rods.

As a result, masses of hydrogen gas have accumulated in the inside top of the reactor building. The gas may cause an explosion similar to that which occurred at the Number One reactor on Saturday.

Tokyo Electric Power Company, also known as TEPCO, is considering ways to remove the hydrogen from the structure.

The Number One reactor and its containment structure are being pumped with seawater in an effort to secure cooling.

[jfchandler]

TEPCO's latest update for Sunday is dated at 3 pm. The most noteworthy portion relates to Daichi Reactor No. 3:

In order to fully secure safety, we operated the vent valve to reduce the pressure of the reactor containment vessels (partial release of air containing radioactive materials) and completed the procedure at 8:41AM, Mar 13 (successfully completed at 09:20AM, Mar 13.)

After that, we began injecting water containing boric acid that absorbs neutron into the reactor by the fire pump from 09:25AM, Mar 13.Taking account of the situation that the water level within the pressure vessel did not rise for a long time and the radiation dose is increasing, we cannot exclude the possibility that the same situation occurred at Unit 1 on Mar 12 will occur. We are considering the countermeasure to prevent that.

Their 2 pm Sunday Daichi Plant update also included the following:

We are currently coordinating with the relevant authorities and departments as to how to cool down the water in the spent nuclear fuel pool.

- We measured radioactive materials inside of the nuclear power station area (outdoor) by monitoring car and confirmed that radioactive

materials level is higher than ordinary level. Also, the level at monitoring post is higher than ordinary level. We will continue to monitor in detail the possibility of radioactive material being discharged from exhaust stack or discharge canal.

Edited March 13, 2011 by jfchandler

[mkawish]

while this is true, there are a number of slightly worrying observations:

- During these 3 to 4 days (and up to a week or so) there need to be water cooling as well

- The fact that they are adding Boron to the water may point to the fact that the reaction is ongoing / maybe the control rods haven't been fully inserted due to warping of the structure by the quake

- They can't confirm on their instruments that the water they are pumping in is actually raising the level in the reactor. Not sure at this time if it is an instrument failure or something else. I don't think they are willing to go in and have a look...

Indeed, there were reports today the rods in Daichi Reactor No. 3 were uncovered by an amount of two meters... And I asked at the time, how can that be when they've been pumping in sea water all day...

Yet somehow, they're apparently able to tell to what extent the reactor cores are not covered by coolant... It's confusing...

Well.... by our standards.... and mostly guesstimation her--they do not really know, they just want to give some answers to stop most questionings....

it is not like in the west.... you are likely to be fired providing misleading info or figure.... to mislead officials or others....

Just.... do not use their figures to do any serious calculations nor juxtapositions.... in any nuclear related matter....

[Lopburi99]

Guys, is this a reasonable conclusion at his point in time -- It appears although there is a fair chance another reactor may suffer further damage similar to the explosion of the first, the threat of a catastrophic event similar to Chernobyl is very very low, and furthermore that the radiation already released is minimal and not a significant health threat. Is this unreasonably optimistic?

[jfchandler]

Guys, is this a reasonable conclusion at his point in time -- It appears although there is a fair chance another reactor may suffer further damage similar to the explosion of the first, the threat of a catastrophic event similar to Chernobyl is very very low, and furthermore that the rReadiation already released is minimal and not a significant health threat. Is this unreasonably optimistic?

Lopburi, let me deal with your questions above separately, as best as I can discern from all the various info:

1. The first explosion at Daichi Reactor 1 was a hydrogen explosion from gases created during the cooling process...not a nuclear explosion. And yes, the Japanese Govt. is saying, and the situation suggests, a similar explosion could well occur at Reactor 3.

2. Re Chernobyl, the general sense is that the types of Japanese reactors and their construction involved are different, and it's unlikely a catastrophic explosion and widespread radioactive dispersion would occur in the Japanese reactors... However, that doesn't mean there couldn't be some type of nuclear dispersing explosion or serious meltdown there. The question would be...how well would that be contained by the reactor containment facility.

3. Thus far, the highest publicly disclosed radiation level in the area of the Fukushima plants was Sunday at amount of above 1500 microSieverts, or 1.5 milliSieverts per hour...which is three times the Japanese regulatory trigger for notifications. Various reports have described those kinds of one hour numbers as being similar to what a normal person receives from natural sources in the course of a full year. Short term it may not be a big problem... but you wouldn't want to be in that kind of exposure for longer terms. And obviously, the less the better.

The one new piece of info that surfaced Sunday was the presence of plutonium as part of the reactor fuel in Daichi Reactor 3. That potentially makes the situation there more unstable and possibly more dangerous in the event of exposure to the environment.

[marc11864]

Another Japanese nightmare... They always pretended that their nuclear power plants were earthquake-resistant and safe for any tremor that could shake the construction.

Now we have another Chernobyl coming up, despite all what they are pretending that there is no immediate threat for the people. Why then evacuate them 20 km away from the plant? Melting is underway and nobody can stop it. It will continue to burn as in Chernobyl, until all nuclear fuel has been burnt and blown in the sky, poisening thousands of sq.km. land and/or ocean. A nuclear powerplant is not like a Toyota car which has been recalled for failing breakes... Will they ever learn???

This is NOT Chernobyl in any sense of the word. The reactor type is different and Chernobyl had major design flaws, not the least of which was that they had no containment vessel whatsoever. The Japanese are not known to cut corners when it comes to nuclear fission.

In other words, relax. :jap:

Relax? http://www.scientificamerican.com/article.cfm?id=fukushima-core&page=2

Yes relax. You're looking at a worst case scenario. There's still quite a way to go before we'd get there. What is the sense of panic at this point?

[ryladie99]

Google LatLong : Google Earth before and after photos from tsunami: http://j.mp/dXGtbP

Thank you so much Thai Visa.com... especially George..I was able to contact with my family members right after your Thursday 11. I stopped my family members from driving near the ocean. It was a night mare on the freeway in the Bay Area. We were scare and panic of what was happening. Keep up your good work. My family heart and Soul feel for the Japanese people. We Silicon Valley live in the Earthquake zone as well. We will urge everyone donate what ever he or she can do to Red Cross and other organizations. That is all we can do, Remember Japanese government did her Best in my personal opinion.

[unblocktheplanet]

You can also take a look what Greenpeace founder Patric Moore has to say about nuclear power. He got fed-up of the ignorant people who got the power within the association.

http://www.washingto...6041401209.html

I have personally known Patrick Moore for nearly forty years. His family clearcut-logged most of the mountains surrounding Winter Harbour on the west coast of Vancouver Island and now 87% of old growth forests—1,600 years old-- on the Island are gone. Following his expulsion from Greenpeace, he went back to his roots and became an apologist for the salmon-farming ocean rapists. And now he’s an apologist for the nuclear industry. Sorry, to quote the Bella Coola tee-shirt: “Patrick Moore is a big, fat liar!"

[unblocktheplanet]

I don’t think you need to know a microsievert from a milliamp to know in your gut when something’s just plain wrong!

Forget about the environment for a minute and the fact that the contaminated, radioactive seawater cooling will be released back into the ocean and live on in all those lovely fish we’ll be eating (remember mercury? remember Minamata disease? anybody out there give up fish?).

Let’s just talk about the money, the real reason behind nuclear power, however well-intentioned.

How much does a reactor cost? A billion dollars maybe? Now let’s look at the number of kilowatt/hours generated and how much electric consumers paid for them. How many years does it take these plants to make a profit? Now, add the cost of ‘decommissioning’ and clean-up (clearly impossible). And all this nuclear waste will be sealed in place, sitting on exactly the same fault-line. Tell me nuclear power makes any kind of sense.

Five kilos of uranium burned in a coal plant in a year. How many kilos of uranium and plutonium did the Japanese plants consume? How many kilos of waste were left over?

Keiji Nakazawa wrote a ten-volume manga series called Barefoot Gen, translated into English, Thai and many other languages, about his boyhood after the bomb in Hiroshima.

http://en.wikipedia.org/wiki/Barefoot_Gen

http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Dstripbooks&field-keywords=Keiji+Nakazawa&x=0&y=0

These books should be required reading for every schoolchild in every country so we never make, at least, that mistake again.

There’s a reason there has never been a thread so read on ThaiVisa as this one...

[Jdietz]

Yeah yeah we now know your stance on Atomic Energy. Could you please move it to a new thread so we can keep factual information / discussion about the current incidents here without turning it into a political battle?

[OzMick]

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

A huge flooding of the downstream area of biblical rather than tsunami proportions. Every rose has a thorn.

[OzMick]

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

Ash and dust from a coal-fired boiler are normally pumped as a slurry to a holding dam where much of the water is recovered/recycled.

Usual practice has been to eventually dump the mess back into a disused open cut mine (where available), more or less putting it back where it came from. The major problem with it is the heavy metal content, mostly cadmium. I have never heard of any concern re radioactivity though.

One old station that I worked at circa 1980 sold boiler dust for cement and road base use.