Japan Earthquake: Nuclear Plants at Fukushima Daiichi

In summary: RCIC consists of a series of pumps, valves, and manifolds that allow coolant to be circulated around the reactor pressure vessel in the event of a loss of the main feedwater supply.In summary, the earthquake and tsunami may have caused a loss of coolant at the Fukushima Daiichi NPP, which could lead to a meltdown. The system for cooling the reactor core is designed to kick in in the event of a loss of feedwater, and fortunately this appears not to have happened yet.
  • #9,136
Borek said:
This is off topic - and tricky. Most of PF users will be able to learn these numbers and to deal with them. Joe Public needs calculator to check how much change he will get from paying $3 for three $0.99 hamburgers. It won't work for him.

Although off topic, as Joette Public myself, my vote would be for the actual numbers in whatever units AND the numbers converted to average background radiation. Even those of us with nonscientific minds have a responsibility to educate ourselves and at least try to understand and/or check with those of you that are better educated. If all fails, the comparison to average background radiation might be helpful, but it alone does not provide an accurate picture of the situation, as explained by the previous poster. And we all, scientists and laymen alike, have a right to get the actual numbers. The environment belongs to all of us.
 
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  • #9,137
well Jorge after my heart stress (thallium i think it was )test i was >3 mr/h so you'd have got ten or so microsv sitting beside me in an airplane flight.

folks should be aware the conversion from Bq to dose , sv or r , is dependent on the isotope that's why Wiki qualified that conversion as being for K40. Reason for that is; dose is a measure of absorbed energy (cell damage) and higher energy rays hurt more. it's frustrating trying to get a feel for Bq to Sv or R.
Wish i knew what's a middle-of-the-road conversion factor but truth is rays can vary in intensity by 8 orders of magnitude, so the conversion factors do too.

There ought to be a "good guess" factor to use for the iodine and cesium the public is most apt to encounter from Fukushima. Maybe there's a practical minded expert on board?

jim
 
  • #9,138
Antisocial, from the lunaticoutpost, who in the past has demonstrated to be one of the most conservative posters in their Fukushima thread, and undoubtedly a current or ex Nuclear worker with expertize in fission and nuclear reactors has just posted the following:
"The individual I know, along with all of her co-workers that were operating weather stations early on are being treated for internal radiation exposure...
...the number of people exposed to considerable danger during the first week is enormous, and many in the JDF are furious with the government and TEPCO for understating or hiding ... Most have had a pretty good idea what went on for the past few weeks, but as it becomes public they can no longer pretend, and the anger is growing. Humiliated is the word I've heard used a lot, and that's a strong word in Japan.

Just to re-iterate, somewhere between 15% and 35% of the core of #3 was ejected up during the explosion. The remainder was forced down. Its assumed the pressure vessel was damaged and this core material is below it now. The explanation I've seen for the modulation of the radiation is that as water seeps into the primary containment, it acts as a moderator/reflector and when it reaches a "critical" depth, it reflects enough energy back into some of the material that it re-achieves criticality. Once this happens the heat created begins driving off the water and the reaction slows. Remember, water between fuel slows the reaction between the fuel, but water surrounding fuel enhances the reaction. The danger here is a large storm could swamp the building and the water could get deep enough that it can't be driven back by the heat, and a potential explosion could result.

One and Two are melted utterly. No one who values their life will come anywhere near those containments for years to come.

Fuel pools are wildcards. ...
Three is a done deal. Nothing at all can be done about it...

... One is believed to have ablated through the floor to some extent based on seismology readings that aren't being made public. There are sensitive sensors all around the grounds listening for underground activity, as well as satellite based imagery used to locate bunkers and tunnels that can image the ground density. 1300C material generates pressure underground that alters the density of the ground, and these changes can be detected and visualized. It's also theorized that this pressure underground is what's driving the water into the other buildings. As hydrostatic pressure builds moving away from the underground source, the water is pushed up and away and is finding the path of least resistance into other buildings. ...there are volumes of real information being created daily. The level of information being made public is the equivalent of what TEPCO would have known in 1975. It's 2011.

..."
http://lunaticoutpost.com/Topic-Nuclear-Power-plant-Onagawa-on-fire-Fukushima-malfunctions?pid=1231435#pid1231435
 
  • #9,139
Bioengineer01 said:
In the video the ejecta phase happens a lot sooner than in the Unit 3 explosion, also the plume doesn't go as high by a large margin. Somebody with good video analysis equipment could quantify this differences, any takers?

Quantify what? It's as easy for you as for anyone else to estimate the speed of the respective plumes. But what good would that do?
 
  • #9,140
Bioengineer01 said:
Just to re-iterate, somewhere between 15% and 35% of the core of #3 was ejected up during the explosion.

Any source to that claim, or is it just some post by someone at some forum?
 
  • #9,141
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  • #9,143
zapperzero said:
Quantify what? It's as easy for you as for anyone else to estimate the speed of the respective plumes. But what good would that do?
Nothing really, only prove my point that they are way different and not similar phenomena. But doesn't help. I am just frustrated by the lack of detailed information coming out...
 
  • #9,144
Borek said:
Any source to that claim, or is it just some post by someone at some forum?
It is a post from somebody at some forum, but somebody that has posted data in advanced consistently since the event and that has demonstrated to have inside connections with people at Fukushima. I know he could be using his established reputation to now spread misinformation, but he hasn't done so before. You could easily go to "some forum" and search for his historical posts and make up your mind on his credibility or lack thereof. But given the scarcity of truth that has come out in time from TEPCO and the Japanese government and the track record of this guy. I'd advice to not dismiss it out of hand without first checking out his track record.
 
  • #9,145
elektrownik said:
Can anyone explain me this graph at page 3, there is big jump in I-131 level between 5/27 and 5/31: http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110607e8.pdf
And, as we are at this, can somebody explain the increase in I-131 reported by Tepco in between this two reports on the same timeframe as the increase in the previous chart, inside the silt fence of Unit 2 from 5200 Bq/L to 24000 Bq/L, may the scaling factor, something I don't understand has something to do with it, since it changes from 130 to 600 in the measurements of the 2 days. Comments will be appreciated:
For 5/27/11: http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110528e5.pdf
For 5/28/11: http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110529e3.pdf
 
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  • #9,146
Bioengineer01 said:
I am wondering if these pictures of Reactor 3 and the analysis that goes with them have been discussed in the thread. They seem very informative to me. Comments?

http://www.houseoffoust.com/fukushima/R3.html

How about if you start perusing the thread and don't stop until you finish? Much insight can be gained that way. I myself came in at about page 300, but I don't remember asking for others to do my homework for me.

Yes, most everything that's on houseoffoust was discussed here. Nancy herself was here, actually, discussing photos of #4 reactor. She re-posted most of those photos from Cryptome, btw, so you may as well go to the source from now on and save the time that you would otherwise spend on her commentary and interpretations.
 
  • #9,148
zapperzero said:
How about if you start perusing the thread and don't stop until you finish? Much insight can be gained that way. I myself came in at about page 300, but I don't remember asking for others to do my homework for me.

Yes, most everything that's on houseoffoust was discussed here. Nancy herself was here, actually, discussing photos of #4 reactor. She re-posted most of those photos from Cryptome, btw, so you may as well go to the source from now on and save the time that you would otherwise spend on her commentary and interpretations.
Thanks and sorry for abusing. Just trying to keep up with regular work and what is going on at Fukushima is difficult. I will read it as I find time.
 
  • #9,149
Bioengineer01 said:
Nothing really, only prove my point that they are way different and not similar phenomena. But doesn't help. I am just frustrated by the lack of detailed information coming out...

Deflagration vs detonation? Again, you are probably correct. Please, please take the time, do the reading. A study by some Japanese institute wrt this very issue has been recently discussed.
 
  • #9,150
"""Just to re-iterate, somewhere between 15% and 35% of the core of #3 was ejected up during the explosion. The remainder was forced down."""

that's an awfully strong statement to make without backup. I don't buy it at all.

Were it true the scene would have been way more Chernobyl-like and we'd see nobody calmly driving firetrucks, walking around tending equipment and posting radiation signs.

it's easy to scream "FIRE" , it's difficult to sort through information and build a credible train of thought that fits observations.Test any claim by comparing it to observation of reality. Remember Lavoisier's quote: "Instead of applying observation to the things we wished to know, we have chosen instead to imagine them..." not bad for 300 years before computers.

if he backed it up with nuclide analysis of the "highly radioactive debris" noted in NRC's march 26 report i would listen to him. After all, even Don Quixote has some experience with windmills.that's my opinion as an interested observer .
 
  • #9,151
elektrownik said:
Can anyone explain me this graph at page 3, there is big jump in I-131 level between 5/27 and 5/31: http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110607e8.pdf

If I remember correctly they had more than usual amount of rain those days or just before it.

The rain washes contamination from debris into the ground and some of that contaminated water may end in the sub-drain pits / sea.

It's not changing underneath the unit #5 and #6 because there is less debris/contamination there.

Why is it not changing underneath the unit #2? Perhaps there is not so much contaminated debris around it because it had a different type of explosion?

This is just my hypothesis. :wink:
 
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  • #9,152
Bioengineer01 said:
Antisocial, from the lunaticoutpost, who in the past has demonstrated to be one of the most conservative posters in their Fukushima thread, and undoubtedly a current or ex Nuclear worker with expertize in fission and nuclear reactors has just posted the following:
"The individual I know, along with all of her co-workers that were operating weather stations early on are being treated for internal radiation exposure...
...the number of people exposed to considerable danger during the first week is enormous, and many in the JDF are furious with the government and TEPCO for understating or hiding ... Most have had a pretty good idea what went on for the past few weeks, but as it becomes public they can no longer pretend, and the anger is growing. Humiliated is the word I've heard used a lot, and that's a strong word in Japan.

Just to re-iterate, somewhere between 15% and 35% of the core of #3 was ejected up during the explosion. The remainder was forced down. Its assumed the pressure vessel was damaged and this core material is below it now. The explanation I've seen for the modulation of the radiation is that as water seeps into the primary containment, it acts as a moderator/reflector and when it reaches a "critical" depth, it reflects enough energy back into some of the material that it re-achieves criticality. Once this happens the heat created begins driving off the water and the reaction slows. Remember, water between fuel slows the reaction between the fuel, but water surrounding fuel enhances the reaction. The danger here is a large storm could swamp the building and the water could get deep enough that it can't be driven back by the heat, and a potential explosion could result.

One and Two are melted utterly. No one who values their life will come anywhere near those containments for years to come.

Fuel pools are wildcards. ...
Three is a done deal. Nothing at all can be done about it...

... One is believed to have ablated through the floor to some extent based on seismology readings that aren't being made public. There are sensitive sensors all around the grounds listening for underground activity, as well as satellite based imagery used to locate bunkers and tunnels that can image the ground density. 1300C material generates pressure underground that alters the density of the ground, and these changes can be detected and visualized. It's also theorized that this pressure underground is what's driving the water into the other buildings. As hydrostatic pressure builds moving away from the underground source, the water is pushed up and away and is finding the path of least resistance into other buildings. ...there are volumes of real information being created daily. The level of information being made public is the equivalent of what TEPCO would have known in 1975. It's 2011.

..."
http://lunaticoutpost.com/Topic-Nuclear-Power-plant-Onagawa-on-fire-Fukushima-malfunctions?pid=1231435#pid1231435

How plausible is it that the site surrounds are crisscrossed daily by hundreds of workers after having 15-35% of a recently shut down core sprinkled over the landscape?
 
  • #9,153
Borek said:
Any source to that claim, or is it just some post by someone at some forum?


There is a theory which is attractive to some, that the reactor in unit 3 "blew up" on March 14th as at Chernobyl. This theory has nothing to recommend itself to me.
I see no reason to even suspect that the RVP was breached on March 14. If the innards of the RPV had been sprayed about the site as at Chernobyl, the site would be radioactively 'hot" as at Chernobyl and it is clearly not. Further, if one looks at the photo of wreckage of #3, the outline of the equipment crane can be seen lying on top of the area where the containment structure exists, and on top of that, the framework of the roof structure still remains more or less in the same place it had always been. These circumstance could not exist if the reactor "blew up."

IMO the concrete lid(s) for the secondary containment vessel unseated themselves as they were designed to do in the case of overpressure and disgorged a quantity of very hot steam and hydrogen - which initiated the chain of events seen on the video. What happened after that may be debatable but no evidence exists to lead us to think that any contents of the RPV escaped on March 14.

Are you in agreement with this view?
 
  • #9,154
zapperzero said:
How about if you start perusing the thread and don't stop until you finish? Much insight can be gained that way. I myself came in at about page 300, but I don't remember asking for others to do my homework for me.

Yes, most everything that's on houseoffoust was discussed here. Nancy herself was here, actually, discussing photos of #4 reactor. She re-posted most of those photos from Cryptome, btw, so you may as well go to the source from now on and save the time that you would otherwise spend on her commentary and interpretations.

Hey Zapperzero, thanks for the spanking :). I am reading the thread from the start and it is proving VERY illustrative about who is trying to actively minimize the event (now we know the truth a lot more, we don't know how much is still being kept form us), who is posting on an unbiased way and who is pushing to extremes. Very useful exercise! :)
 
  • #9,155
"""no evidence exists to lead us to think that any contents of the RPV escaped on March 14.

Are you in agreement with this view? ""

the strongest evidence of a March 14th breach is to me officialdom's deafening quiet about it and avoidance of pictures.

It is a useful thought tool to push a thought to its logical limit then back up to reasonable-ness.

For an upper logical limit , I find it plausible the vessel head bolts stretched relieving steam but the steam separators/dryers acted as a collander keeping debris inside..

with that as my accepted worst case i can judge other hypotheses against photographs and Jorge's graphs.

Lesser ones i consider,

more radical ones i discard.

but that's just my way of thinking.

old jim :smile:
 
  • #9,156
zapperzero said:
Deflagration vs detonation? Again, you are probably correct. Please, please take the time, do the reading. A study by some Japanese institute wrt this very issue has been recently discussed.

Oh, I followed that in detail, I even tried to get to the source of their assumptions, but unsuccessfully. I am missing up to page 450, although I have been following the event on other threads, and reading this thread on and off, it is just that my technical/scientific background was hungry for more analytical minds with physics/engineering background to discuss with...
 
  • #9,157
Bioengineer01 said:
It is a post from somebody at some forum, but somebody that has posted data in advanced consistently since the event and that has demonstrated to have inside connections with people at Fukushima.

The problem I have with the idea was already mentioned in the meantime. Fuel rods lying everywhere will mean much higher radiation levels than those observed, both in the area and far outside. That wouldn't be something possible to hide. Inside - they wouldn't be able to even take pictures they show (I mean those with people working, investigating, visiting and so on). Outside - too many eyes and sensors - from many countries, from many organizations - vigorously testing air, water, everything.
 
  • #9,158
Testing everything except the steam coming directly out of what used to be reactor building three.
 
  • #9,159
robinson said:
Testing everything except the steam coming directly out of what used to be reactor building three.

I am not writing about tests on site, but tests done far from the site.

Besides, if the steam was seriously radioactive, I guess we would know about it - for the reasons listed in my previous post.

I am not stating TEPCO should not test, I am not stating they are right not publishing results if they do. All I am saying is - I don't believe they could cover something like that for long, when everyone and his dog buys radiation sensors on eBay and sticks them through the window.
 
  • #9,160
Borek said:
Any source to that claim, or is it just some post by someone at some forum?

It up to you to disprove it Borek. What percentage of fuel assemblies have to vaporize and release into the atmosphere to cause the amount of fallout so far discovered locally and worldwide? You owed it to the people who are not as smart as you.
 
  • #9,161
Desperate attempts by plant workers to vent pressure to prevent the containment vessels from bursting repeatedly failed. Experts have said the delay in venting was a primary cause of explosions that further damaged the reactors and spewed huge amounts of radiation into the air. The report also noted the outermost containment buildings should have had vents to prevent a series of explosions at three units.

The melted cores and radiation leaks have irradiated workers, including two control room operators whose exposures have exceeded the government limit.

http://news.yahoo.com/s/ap/ap_on_bi_ge/as_japan_earthquake
 
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  • #9,162
Borek said:
The problem I have with the idea was already mentioned in the meantime. Fuel rods lying everywhere will mean much higher radiation levels than those observed, both in the area and far outside. That wouldn't be something possible to hide. Inside - they wouldn't be able to even take pictures they show (I mean those with people working, investigating, visiting and so on). Outside - too many eyes and sensors - from many countries, from many organizations - vigorously testing air, water, everything.

I hope that you are right, although given that I am reading the thread from page 1 on right now, with the benefit of today's knowledge and knowing of some recognized TEPCO's confessions and exposed coverups. I am finding that the worst case scenarios presented from the beginning were the most accurate ones, and the vanilla ones were off by a long shot. If I didn't think it would be considered inappropriate I would be re-posting some of the statements made at the beginning of this thread that would make us feel very gullible and infantile in our willingness to believe what we were being told. I highly recommend re-reading even for those of you that have been here all along... Very educative...
 
  • #9,163
Calm down with ejected fuel idea, it is simple - if it would be ejected all peoples which were working there would die in not more than one day...
 
  • #9,164
razzz said:
It up to you to disprove it Borek. What percentage of fuel assemblies have to vaporize and release into the atmosphere to cause the amount of fallout so far discovered locally and worldwide? You owed it to the people who are not as smart as you.
You forgot the snark tag ;)

Seriously, it is up to the claimant to prove their claims, not the other way around.

However, I do have a question related to this that I think will help with the repeated statements about reactors blowing up, reactor lids being blown off, etc.

I don't recall seeing an estimate on this thread of radiation levels if, indeed, there were fuel rods lying about the site. For example, what would the Sv/hr readings look like for one fuel rod from #3 look like if it were lying out on the grass? I don't have a clear concept of the magnitude. Thanks.
 
  • #9,165
razzz said:
It up to you to disprove it Borek. What percentage of fuel assemblies have to vaporize and release into the atmosphere to cause the amount of fallout so far discovered locally and worldwide? You owed it to the people who are not as smart as you.

This is neither how science nor logic works. The onus of proof is on those making claims, not those skeptical of the claims.
 
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  • #9,166
razzz said:
It up to you to disprove it Borek. What percentage of fuel assemblies have to vaporize and release into the atmosphere to cause the amount of fallout so far discovered locally and worldwide? You owed it to the people who are not as smart as you.

It's not up to anyone to disprove anything in the absence of solid data - and nobody (even the workers at Tepco) have the data to say what happened to the core in Unit 3.

I believe your post (unless others see it as 'banter') is against the spirit of this scientific forum.
 
  • #9,167
Bioengineer01 said:
If I didn't think it would be considered inappropriate I would be re-posting some of the statements made at the beginning of this thread that would make us feel very gullible and infantile in our willingness to believe what we were being told.

I know just what you mean. But it would be appropriate for the political threads, this one has quite enough with the speculations about what happened, is happening, and might happen.
 
  • #9,168
razzz said:
It up to you to disprove it Borek. What percentage of fuel assemblies have to vaporize and release into the atmosphere to cause the amount of fallout so far discovered locally and worldwide? You owed it to the people who are not as smart as you.
Well, such a calculation would not be understood by those people. I believe that the accident has been and still is downplayed a lot be the Japanese . But ejection of a significant part of the reactor core? Never! Look at Chernobyl. Look at the pictures and films. You can see flashes on them everywhere - flashes from the ambient radiation. These were all cameras without electronics. I bet a modern electronic camera would have failed immediately. Look at the firemen who were fighting the fire immediately after the explosion. They all became sick after some hours and most of them died after a month or so.

Whatever exploded in unit #3 - the core must have stayed in the containment.
 
  • #9,169
westfield said:
Here is a short clip of the steam emanating from the north side of the containment "void".

At other times it's been more active like in this poor quality image

http://i1185.photobucket.com/albums/z360/fukuwest/misc/sfpinRB302.jpg

Those releases appear to me to be coming from the containment structure, although; I will agree that there is a possibility they are coming from north of the containment.

But there is nothing that i know of to the north of the containment structure that could be a source of steam release, except steam from a leak or broken pipe lower in the containment structure which finds its way out there.

But that still leaves the two sources of steam as being the containment structure and the SFP.

What do you think?
 
  • #9,170
joewein said:
Yes, there's a nearby dam. That's where they got their freshwater from.

Which once again points out how unfortunate it is that we are lacking a poster knowledgeable of the subject of geology.

It simply can't be true that the underground rock formations, water tables and streams at the Fukushima site are an unknown.

Somebody did the engineering for that dam.
 

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