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.
  • #12,496
jmelson said:
Unloading the fuel from that pool will be a very tricky bit of work using a traditional crane which has no way to orient the hook like a FHM does. The unused fuel
can just be pulled out, the old fuel might be able to be removed under water deluge, but the
recently burned fuel will be quite a challenge to remove. Possibly they can still use transfer
casks to get it out of there, one element at a time.
My thought was that they might construct a water channel and tower on one side of the spent fuel pool, then take fuel out into a (new) ground-level pool through a lock, in water the whole time. But there might be craned solutions that are simpler and indeed safer over the whole operation.

al2207 said:
it is Pickering in Ontario
- or Bruce on Lake Huron. But the same considerations apply.
 
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  • #12,497
http://pbadupws.nrc.gov/docs/ML1110/ML11102A041.pdf

MEMBER CORRADINI: The only reason I ask the question is, from the same public sources I think we are all looking at, Unit 1 is the only one that is showing pressurized.

MR. RULAND: That's correct.

-----

MEMBER ARMIJO: I've been there, (Japan) you know from a hazy recollection, they were very similar, if not identical, to the U.S. plants. But I have heard all sorts of stories that they were different, and I had wondered -- I would like to know if the NRC has drawings of the plants as they currently exist.

The other thing I know about the Japanese, they were very careful to follow the safety upgrades that the NRC required in the U.S. plants---CHAIRMAN ABDEL-KHALIK: Now, with regard to the spent fuel pools, it is my understanding that the emergency operating procedures used by the Japanese are similar to those used at U.S. plants.

And for both BWRs and PWRs, the emergency operating procedures focus on maintaining the critical safety functions of the reactor.

Nowhere in the EOPs are the operators asked to check the status of the spent fuel pools.

Given what happened at Fukushima with regard to the spent fuel pools, should the licensees be asked to evaluate the adequacies of their EOP?---

And with a hardened vent -- the vent, prior to the venting operation, still filled with oxygen, so the chance of a deflagration inside the vent is real, if you vent hydrogen through that.
 
  • #12,498
jmelson said:
Unloading the fuel from that pool will be a very tricky bit of work using a traditional crane which has no way to orient the hook like a FHM does.

As I understand this for unit 4 they will use external cranes only to move the transfer casks to- and from the pool, and they will repair and use the FHM to move the fuel within the pool to the transfer casks.

But first they will have to repair the FHM of the common pool and start to prepare it to receive the removed fuel from unit 4.
 
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  • #12,499
It looks like that the Fuelhandlingmachine (upper Part) is also removed.
 

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  • #12,500
That's just the overhead crane trolley and the main beams. The FHM is still in place.
 
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  • #12,501
1. Picture: look at the right side. The upper Part is visible.
2. Picture : The upper Part is no longer visible.
3. Picture: Left side, maybe there is the upper part of the FHM.
 
  • #12,502
Oooops. Yes, you are right. That thing on the third picture is the trolley of the FHM.
 
  • #12,503
http://www3.nhk.or.jp/news/genpatsu-fukushima/20120307/0920yoken.html At a symposium in Washington about the Fukushima Daichi accident, Commissioner Apostolakis said "the consequences of a tsunami could have been predicted". The symposium organiser, the Carnegie Endowment for Peace, is also releasing a report on "Why Fukushima was preventable", saying that the analysis of historical tsunamis was not sufficient and that in contrast with the measures taken in Europe after the French NPP flooding and blackout of 1999 or in the US after the 11 September 2001 attacks, Japan was negligent to take countermeasures against blackout.

http://carnegieendowment.org/2012/03/06/one-year-on-assessing-fukushima-s-impact/9iid Symposium

http://carnegieendowment.org/files/fukushima.pdf report: James M. Acton and Mark Hibbs, "Why Fukushima was preventable"
 
  • #12,504
tsutsuji said:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20120307/0920yoken.html At a symposium in Washington about the Fukushima Daichi accident, Commissioner Apostolakis said "the consequences of a tsunami could have been predicted". The symposium organiser, the Carnegie Endowment for Peace, is also releasing a report on "Why Fukushima was preventable", saying that the analysis of historical tsunamis was not sufficient and that in contrast with the measures taken in Europe after the French NPP flooding and blackout of 1999 or in the US after the 11 September 2001 attacks, Japan was negligent to take countermeasures against blackout.

http://carnegieendowment.org/2012/03/06/one-year-on-assessing-fukushima-s-impact/9iid Symposium

http://carnegieendowment.org/files/fukushima.pdf report: James M. Acton and Mark Hibbs, "Why Fukushima was preventable"

Seems nuclear management in Japan after thirty plus years of operations free from disaster suffered from the same 'Victory Disease' as that which afflicted Japanese leadership in the early days of WW2.
It is very hard to stay careful when things work well for a long time.
 
  • #12,505
Rive said:
As I understand this for unit 4 they will use external cranes only to move the transfer casks to- and from the pool, and they will repair and use the FHM to move the fuel within the pool to the transfer casks.

But first they will have to repair the FHM of the common pool and start to prepare it to receive the removed fuel from unit 4.

Ok, that seems a lot safer, but the problem is that repairing the FHM and being sure it is completely reliable will be a huge effort, due to the structural damage to the entire building. The FHM itself could be pulled out by crane and moved elsewhere for repairs, but the tracks it runs on have to be guaranteed to handle the load and be transited in so the FHM can travel in the proper plane.

Jon
 
  • #12,506
etudiant said:
Seems nuclear management in Japan after thirty plus years of operations free from disaster suffered from the same 'Victory Disease' as that which afflicted Japanese leadership in the early days of WW2.
It is very hard to stay careful when things work well for a long time.

See also Challenger accident and Columbia accident. "It hasn't killed anybody yet, so it can't be a big risk."

Jon
 
  • #12,507
jmelson said:
See also Challenger accident and Columbia accident. "It hasn't killed anybody yet, so it can't be a big risk."

Jon
That's a half-appropriate comparison. Yes organizations can and have misjudged the risk of accidents, but clearly the consequences of the one (Challenger) means 100% fatalities, while the other with containment equipped reactors means large capital losses and economic damage, but zero fatalities, so far.
 
  • #12,508
tsutsuji said:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20120307/0920yoken.html At a symposium in Washington about the Fukushima Daichi accident, Commissioner Apostolakis said "the consequences of a tsunami could have been predicted".
Wow, what an understatement! Anybody who was analyzing safety should have put this together pretty easily. It seems the Japanese government allowed TEPCO WAY too much
leeway to set their own rules and safety management.

But, of course, anybody who was let into give Fushima Dai-ichi #1 a complete review
would have demanded it be shut down immediately. And, the rest of the plants there would have only gotten a slightly better review. There were so MANY features of the plant that compromised survivability, it would have made it almost impossible to bring these plants up to reasonable standards. Once you put practically the entire electrical safety system in the basement of a building only meters from the ocean, both horizontally and verticaly, you have a HUGE problem. Then, there was so much ELSE vulnerable to the tsunami, like EDG fuel tanks. Just a mess. Fixable, but it would cost a couple billion $ to retrofit just the plants
at this one location.

Jon
 
  • #12,509
mheslep said:
That's a half-appropriate comparison. Yes organizations can and have misjudged the risk of accidents, but clearly the consequences of the one (Challenger) means 100% fatalities, while the other with containment equipped reactors means large capital losses and economic damage, but zero fatalities, so far.
There indeed WERE fatalities at the plant, although not related to safety systems, but just
people being at the lower levels of the buildings when the tsunami came in. it is kind of a miracle
nobody was killed by falling debris, etc. when the explosions happened.

This accident has caused major radioactive contamination of a large area of Japan, deaths are really hard to associate with such an event, but this is a HUGE, widespread consequence that is not over yet. Radioactive soil will be dug up and cause further contamination for years to
come. There are still areas where farming is not permitted, produce will need to be tested
for radioactivity for years, it is a HUGE mess. The entire nation of Japan will have a big power shortage this summer, it will be interesting to see how they cope with it. It is definitely affecting their whole national economy.

But, I was mostly trying to draw a comparison between assessing risk in very complicated systems, and the cultures that manage such systems.

Jon
 
  • #12,510
jmelson said:
There indeed WERE fatalities at the plant, although not related to safety systems,
Though not related to anything having to do with nuclear power.
 
  • #12,511
mheslep said:
but clearly the consequences of the one (Challenger) means 100% fatalities, while the other with containment equipped reactors means large capital losses and economic damage, but zero fatalities, so far.

So you're saying that seven dead people are worse than 100.000 displaced people, hundreds of square kilometres literally lost and economic losses in the range of dozens or hundreds of billions of dollars?

Oh, of course, from a purely naive and moralistic view, of course, the seven dead are way worse. Since, they are dead and all those displaced still have their lives and human lifes can't be compared to money anyway...

But that's wrong. Life is no pony farm. Those seven astronauts died and with them billions of tax money disintegrated, but then there's no major future impact to the lifes of other people. They may be dead, but it doesn't affect anyone except their families and NASA managers.
As for Fukushima, nobody died, that's right. But hundreds of thousands of lifes are HEAVILY affected, you could even say derailed - for DECADES. Millions, if you count the economic ramifications in.
 
  • #12,512
mheslep said:
Though not related to anything having to do with nuclear power.

at least 1 worker was killed when tsunamis, hit he was investigating if there were some damage from earthquake
 
  • #12,513
There is clearly a problem in maintaining alertness, whether individually or in large organizations, in a long term situation.
Afaik, the SSBN program in the US Navy has done so pretty well, certainly better than the USAF's SAC counterpart, now melded into a generic 'Strike Command['. This latter group was in the news a few years back because a B52 with a half dozen live nukes on board hopscotched across the US, oblivious to the detailed rules on nuclear weapons transport. The head of the USAF was relieved as a result.
My guess is that a periodic human sacrifice of that type is essential to maintain focus.
If so, the problem of the Japanese nuclear program is that they allowed too few flaming public failures. If someone had been pilloried after the leaks at the Monju breeder project for instance, instead of a general whitewash, I am sure the managers at Fukushima would have been more vigorous in demanding better tsunami defenses.
I might add that imho the current Japanese government's insistence that 'no one was responsible' for this disaster guarantees a bigger one next time.
 
  • #12,514
clancy688 said:
So you're saying that seven dead people are worse than 100.000 displaced people, hundreds of square kilometres literally lost and economic losses in the range of dozens or hundreds of billions of dollars?
.

Why don't you ask if any of the 100,000 displaced people would rather be dead instead of displaced. I think we know the answer.
 
  • #12,515
etudiant said:
My guess is that a periodic human sacrifice of that type is essential to maintain focus.
If so, the problem of the Japanese nuclear program is that they allowed too few flaming public failures. If someone had been pilloried after the leaks at the Monju breeder project for instance, instead of a general whitewash, I am sure the managers at Fukushima would have been more vigorous in demanding better tsunami defenses.
I might add that imho the current Japanese government's insistence that 'no one was responsible' for this disaster guarantees a bigger one next time.
The Fukushima plant was not "defendable", in my opinion. Defenses might have helped, but the whole plan of the system was so fatally flawed that it would have taken insane
effort to protect the plant as it was sited. And, fixing one of the major flaws would have required getting practically all the electrical equipment out of the basement. This plant could have been damaged by a major leak in a similar manner, it doesn't have to be a tsunami.

Well, as for the future, at least so far, many of the older coastal plants are now shut down, and it may be politically impossible to restart those, even if they wanted to.

Jon
 
  • #12,516
mheslep said:
Though not related to anything having to do with nuclear power.

There WILL be fatalities from this accident, but it will be essentially impossible to know which persons died from it. In five, ten or maybe twenty years there will be a clear increase of cancers and related diseases. It certainly won't be a HUGE increase, like those laughably insane reports that there were already tens of thousands of deaths in the US that were circulating on some wacko blogs last fall. But, there is quite likely to be a measurable and statistically significant effect on the Japanese population, given the sizable radiation dose that was released.

Jon
 
  • #12,518
mheslep said:
..clearly the consequences of the one (Challenger) means 100% fatalities, while the other with containment equipped reactors means large capital losses and economic damage, but zero fatalities, so far.

There have been plenty of fatalities related to the release of radiation from the three meltdowns, fires and explosions at Fukushima 1.

There was a huge evacuation as result of the ongoing radiation release. During this evacuation, many people died. It is readily apparent that there is a connection between these events.

http://mdn.mainichi.jp/features/archive/news/2011/04/20110426p2a00m0na006000c.html [Broken]

It is obvious there has been tremendous property, and psychological damage as well.

I recommend the contamination & consequences thread if you are interested in learning about some of the dangers of nuclear power.
 
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  • #12,519
Some background recently published.
Code:
Unit 1
Cycle    BOC Date     EOC Date
  25   03 Nov 2007  17 Oct 2008
  26   18 Apr 2009  25 Mar 2010
  27A  29 Jul 2010  22 Aug 2010
  27B  27 Sep 2010  11 Mar 2011

Unit 2
Cycle    BOC Date    EOC Date
  23   28 Jan 2007  12 Mar 2008
  24   24 May 2008  22 Apr 2009
  25A  21 Jun 2009  17 Jun 2010
  25B  19 Jul 2010  16 Sep 2010
  26   18 Nov 2010  11 Mar 2011
  
Unit 3
Cycle    BOC Date    EOC Date
  22   07 Jul 2006  31 Aug 2007  Outage: 15 Jun - 2 Aug
  23   14 Dec 2007  24 Feb 2009
  24   10 Jul 2009  19 Jun 2010
  25   23 Sep 2010  11 Mar 2011

Code:
Unit 4
Cycle    BOC Date    EOC Date
  22   02 May 2007  28 Mar 2008
  23   17 Jul 2008  29 Sep 2009
  24   30 Nov 2009  30 Nov 2010  Shutdown 101 days before tsunami
  
Unit 5
Cycle    BOC Date    EOC Date
  22A  13 Nov 2006  20 Feb 2007
  22B  26 Apr 2007  20 Jan 2008
  23   22 Jun 2008  01 Sep 2009
  24   02 Nov 2009  02 Nov 2010 Shutdown 67 days before tsunami
  
Unit 6
Cycle    BOC Date    EOC Date
  20   06 Jun 2006  30 Sep 2007
  21   08 Feb 2007  11 Mar 2009
  22   12 Jun 2009  14 Aug 2010 Shutdown 209 days before tsunami
The units were mostly on annual cycles, although units 5 and 6 were managing 13 to 14 month cycle lengths.
Unit 4, Cycle 23 was ~14.5 mo, Cycle 24 was 12 month.

Refueling/Maintenance outages were long by current (modern) standards. The plants were operating at original ratings and had relatively low capacity factors by modern standards. I'll post the source later.
 
  • #12,520
Are there any news about the cause of the explosion of unit3?

I didn't follow this issue for quite some time...
For units 1 and 4 I think the explosions were caused most likely by hydrogen within the reactor building.
 
  • #12,523
zapperzero said:

Heavily redacted, lots of speculation , very much in line with chaotic conditions back then..

Misinformation about state of unit 4 spent fual pool, they thought it was gone
speculation on conditions

mean, the dose sounds like not as much
2 a shine from the building as when the building blew
3 up. There is spent fuel and pellets and whatever all
4 over the place around the plant. So they are taking
the bulldozers through and pushing the rubble in
6 piles, and they are saying that's cutting the dose
7 down, you know, 60, 70 percent.
p 74, and i wouldn't bet much on that being accurate.


Are there any news about the cause of the explosion of unit3?
Even the Frontline show was silent on that one.
 
  • #12,524
Personally I don't see the point in taking any of those details from the early days transcript seriously. Because its an experience we all went through in our own way at various stages of talking about the events on forums such as this one. Loads of confused details, stuff that turned out to be dead wrong, or speculation that may have lead somewhere interesting but for which no subsequent evidence emerged with which to build upon.

Now its always possible that previously undisclosed information will be released that will give cause to reconsider something, but when it comes to stuff such as explosions I would think it more likely that the knowledge about this stuff will not be greatly expanded upon, not directly anyway. For example if you are interested in the reactor 3 explosion then I am not quite sure what you are hoping to discover about the explosion. The timing of the explosions at both reactors 1 & 3 happening not long after venting is pretty compelling, and there is an uncontroversial source of hydrogen, several ways for the hydrogen to get into the buildings upper floors, and well understood triggers for that hydrogen to explode. The most you will get is that one day we are going to hear some more detail about factor 3's spent fuel pool, and the state of the fuel there could potentially renew a discussion about this pool having played a role in events at reactor 3 building. And at some point we might get a little more info about containment failure.
 
  • #12,525
Personally I don't see the point in taking any of those details from the early days transcript seriously. Because its an experience we all went through in our own way at various stages of talking about the events on forums such as this one. Loads of confused details, stuff that turned out to be dead wrong, or speculation that may have lead (led?) somewhere interesting but for which no subsequent evidence emerged with which to build upon.

Thanks for saying it more eloquently.

That's where i am at too, we just don't know.
I'm done with speculating.
Waiting to see what pans out.
 
  • #12,526
SteveElbows said:
Personally I don't see the point in taking any of those details from the early days transcript seriously.

All the other numbers I've seen in there jive with TEPCO/NISA and later reports. The interpretation is all NRC, of course, and some of it turned out to be quite wrong.
 
  • #12,527
SteveElbows said:
The most you will get is that one day we are going to hear some more detail about rector 3's spent fuel pool, and the state of the fuel there could potentially renew a discussion about this pool having played a role in events at reactor 3 building.

Well I happen to think I just posted such a detail.
 
  • #12,528
zapperzero said:
Well I happen to think I just posted such a detail.

Well I was meaning new detailed information about the pool and its contents, but certainly the rate you mention is of interest to this question.

I'm not used to working with R per hour numbers, did a conversion but am unsure if I did it right or not. Is 375 R/hour = 3.75 Sieverts/ hour?
 
  • #12,529
SteveElbows said:
Well I was meaning new detailed information about the pool and its contents, but certainly the rate you mention is of interest to this question.

I'm not used to working with R per hour numbers, did a conversion but am unsure if I did it right or not. Is 375 R/hour = 3.75 Sieverts/ hour?

Your conversion is correct. 1 Sv = 100 Rem.

zapperzero said:
Well I happen to think I just posted such a detail.

ZZ, your detail is without context . A radiation reading was taken above the Unit 3 and, and if correct, was recorded at 3.75 Sv/hr. That is the detail. The context requires interpreting what the detail tells us. Was the high radiation due to loss of shielding water level from the spent fuel pool? Was the level from a release plume from damaged fuel in the SFP? Was the drywell Cap displaced? Was the level from shine from the drywell? Was the level from an ongoing release plume due to containment leakage? If the radiation was from I-131 it would indicate recently irradiated fuel. If it was all gamma radiation it would indicate shine instead of a plume. What is the radiation level today? We don't know enough to really say what it meams.
 
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  • #12,530
SteveElbows said:
Well I was meaning new detailed information about the pool and its contents, but certainly the rate you mention is of interest to this question.
It says "strong possibility of uncovered fuel" to me.

I'm not used to working with R per hour numbers, did a conversion but am unsure if I did it right or not. Is 375 R/hour = 3.75 Sieverts/ hour?

100 Rem is 1 Sv, yes.
 
<h2>1. What caused the Japan earthquake and subsequent nuclear disaster at Fukushima Daiichi?</h2><p>The Japan earthquake, also known as the Great East Japan Earthquake, was caused by a massive underwater earthquake that occurred on March 11, 2011. The earthquake had a magnitude of 9.0 and was the strongest ever recorded in Japan. The earthquake triggered a massive tsunami, which caused extensive damage to the Fukushima Daiichi nuclear power plant and led to a nuclear disaster.</p><h2>2. What is the current status of the nuclear reactors at Fukushima Daiichi?</h2><p>As of now, all of the nuclear reactors at Fukushima Daiichi have been shut down and are no longer in operation. However, the site is still being monitored for radiation levels and there is an ongoing effort to clean up the radioactive materials that were released during the disaster.</p><h2>3. How much radiation was released during the Fukushima Daiichi nuclear disaster?</h2><p>According to the International Atomic Energy Agency, the Fukushima Daiichi nuclear disaster released an estimated 10-15% of the radiation that was released during the Chernobyl disaster in 1986. However, the exact amount of radiation released is still being studied and debated.</p><h2>4. What were the health effects of the Fukushima Daiichi nuclear disaster?</h2><p>The health effects of the Fukushima Daiichi nuclear disaster are still being studied and monitored. The most immediate health impact was the evacuation of approximately 160,000 people from the surrounding areas to avoid exposure to radiation. There have also been reported cases of thyroid cancer and other health issues among those who were exposed to the radiation.</p><h2>5. What measures have been taken to prevent future nuclear disasters in Japan?</h2><p>Following the Fukushima Daiichi nuclear disaster, the Japanese government has implemented stricter safety regulations for nuclear power plants and has conducted stress tests on all existing plants. They have also established a new regulatory agency, the Nuclear Regulation Authority, to oversee the safety of nuclear power plants. Additionally, renewable energy sources are being promoted as a more sustainable and safer alternative to nuclear power in Japan.</p>

1. What caused the Japan earthquake and subsequent nuclear disaster at Fukushima Daiichi?

The Japan earthquake, also known as the Great East Japan Earthquake, was caused by a massive underwater earthquake that occurred on March 11, 2011. The earthquake had a magnitude of 9.0 and was the strongest ever recorded in Japan. The earthquake triggered a massive tsunami, which caused extensive damage to the Fukushima Daiichi nuclear power plant and led to a nuclear disaster.

2. What is the current status of the nuclear reactors at Fukushima Daiichi?

As of now, all of the nuclear reactors at Fukushima Daiichi have been shut down and are no longer in operation. However, the site is still being monitored for radiation levels and there is an ongoing effort to clean up the radioactive materials that were released during the disaster.

3. How much radiation was released during the Fukushima Daiichi nuclear disaster?

According to the International Atomic Energy Agency, the Fukushima Daiichi nuclear disaster released an estimated 10-15% of the radiation that was released during the Chernobyl disaster in 1986. However, the exact amount of radiation released is still being studied and debated.

4. What were the health effects of the Fukushima Daiichi nuclear disaster?

The health effects of the Fukushima Daiichi nuclear disaster are still being studied and monitored. The most immediate health impact was the evacuation of approximately 160,000 people from the surrounding areas to avoid exposure to radiation. There have also been reported cases of thyroid cancer and other health issues among those who were exposed to the radiation.

5. What measures have been taken to prevent future nuclear disasters in Japan?

Following the Fukushima Daiichi nuclear disaster, the Japanese government has implemented stricter safety regulations for nuclear power plants and has conducted stress tests on all existing plants. They have also established a new regulatory agency, the Nuclear Regulation Authority, to oversee the safety of nuclear power plants. Additionally, renewable energy sources are being promoted as a more sustainable and safer alternative to nuclear power in Japan.

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