Japan Earthquake: Political Aspects

[tsutsuji]

http://www.yomiuri.co.jp/feature/20110316-866921/news/20120216-OYT1T01050.htm The Fukushima prefecture nuclear energy public relations organization has unanimously decided to dissolve. It was funded by Fukushima prefecture and 11 cities and towns. It published a magazine 4 times a year. They stopped their activity in March as their office is in the restricted zone in Ookuma town. They explain : "We have been doing public relations about nuclear safety, but with the Tokyo Electric Fukushima Daiichi plant accident, the prerequisite has collapsed".

 

[LKofEnglish]

First time poster. Came over from a site called Zero Hedge. Saw a story about potential recriticality at FD and thought I would chime in here first as my only nuclear experience came from studying Chemistry in HS. My question is this: how can anyone really expect to improve the situation without their being some purpose or reason to trust those who inform us? I have more to add but I would curious to hear what you all think about "disclosure after a nuclear accident." thanks.

 

[zapperzero]

My question is this: how can anyone really expect to improve the situation without their being some purpose or reason to trust those who inform us?

TEPCO has been doing a lot of heel-dragging, blame-shifting and general obfuscation.

But, the stuff that can be checked out by and large checks out - total radioactive release (source term) estimates they have published are consistent with (independently) observed contamination, for example. Results of the modeling TEPCO use to estimate core damage are also consistent with the observations and calculations others (including people on here) have made. Reported temperatures evolved as expected, by and large. And so on and so forth.

So, it would appear that whatever data is being made public can be trusted. That's not to say that everything that should be made public was or is.

 

[LKofEnglish]

would you argue that Tepco has been this way all along? It seems fairly straightforward to call Tepco's response to the crisis as at best "evolving." Are their dangers of radioactive material spreading through the debris of the tsunami throughout the Pacific Ocean? Why isn't this patently obvious issue even being discussed? What about the possibility of recriticality? "Blaming the instruments" seems rather incredulous. How can one have poor instrumentation on the biggest industrial accident in human history? What about the disposal of nuclear waste into landfills in and around Tokyo Bay? Are these people insane? the list is so long as to beg the question "why are they hiding so much" and not "why does the data fit the image being portrayed." (as a point of reference I'm coming at this issue from the standpoint of a financial person trying to figure out what the Japanese currency is going to do as a result of this catastrophe. currently it is selling off dramatically.) i am here because folks like me are constantly in the need for "all the data" and not merely what we are told to think. is there anyone here who can make "best guesses" as to what they think is in fact going on? anyone here who can explain "what are the implications to recriticality"? what is the implication of radioactive flotsmam washing ashore the islands of Hawaii and the State's of Washington, Oregon and California even if only at the theoretical level?

 

[etudiant]

would you argue that Tepco has been this way all along? It seems fairly straightforward to call Tepco's response to the crisis as at best "evolving." Are their dangers of radioactive material spreading through the debris of the tsunami throughout the Pacific Ocean? Why isn't this patently obvious issue even being discussed? What about the possibility of recriticality? "Blaming the instruments" seems rather incredulous. How can one have poor instrumentation on the biggest industrial accident in human history? What about the disposal of nuclear waste into landfills in and around Tokyo Bay? Are these people insane? the list is so long as to beg the question "why are they hiding so much" and not "why does the data fit the image being portrayed." (as a point of reference I'm coming at this issue from the standpoint of a financial person trying to figure out what the Japanese currency is going to do as a result of this catastrophe. currently it is selling off dramatically.) i am here because folks like me are constantly in the need for "all the data" and not merely what we are told to think. is there anyone here who can make "best guesses" as to what they think is in fact going on? anyone here who can explain "what are the implications to recriticality"? what is the implication of radioactive flotsmam washing ashore the islands of Hawaii and the State's of Washington, Oregon and California even if only at the theoretical level?

The instrumentation deficiencies simply reflect that the reactors have experienced catastrophic damage and are sufficiently radioactive that new instruments could not be installed even with human sacrificial volunteer help.
The radioactive debris claims are pretty far fetched. The tsunami that washed the debris out to sea was over and done with by the time the plant blew up two days later.
The radiation contamination is real, but at levels found elsewhere on Earth in areas people that people live in, in Iran, Brazil, India and parts of China. Getting frantic about burying the debris begs the question what other option exists?
With cancer the cause of death of over 40% of all Japanese, the accident will be difficult to see in the mortality statistics. However, the cleanup will be a $100 billion class dead weight on the Japanese economy.
Recriticality is a concern primarily because the site will take decades to clean up enough for the fuel to be removed. Only then will the situation be safe again.

 

[nikkkom]

would you argue that Tepco has been this way all along? It seems fairly straightforward to call Tepco's response to the crisis as at best "evolving." Are their dangers of radioactive material spreading through the debris of the tsunami throughout the Pacific Ocean? Why isn't this patently obvious issue even being discussed? What about the possibility of recriticality? "Blaming the instruments" seems rather incredulous. How can one have poor instrumentation on the biggest industrial accident in human history? What about the disposal of nuclear waste into landfills in and around Tokyo Bay?

I have no idea what you are talking about. But assuming some mildly contaminated material is indeed used that way - why is that bad? What do you propose instead? Remember - the less contaminated material is, the more there is of it. For example, there will be A LOT (many tons) of ground scraped in various "hot spots" during decontamination, but ground from even the most dirty hot spot is not particularly dangerous. Say, 20000 Bq/kg? As long as no one _eats_ it, it's not a big deal. But where to put all these tons?

Are these people insane?

No.
Are you done with screaming and ready for adult dialogue?

what is the implication of radioactive flotsmam washing ashore the islands of Hawaii and the State's of Washington, Oregon and California even if only at the theoretical level?

There is no radioactive flotsam from Japan. If you'd have just a little bit of common sense, you'd know that.

 

[Yamanote]

Thanks nikkkom, not more to say here.

 

[r-j]

Are their dangers of radioactive material spreading through the debris of the tsunami throughout the Pacific Ocean? Why isn't this patently obvious issue even being discussed?

http://www.europe-solidaire.org/spip.php?article23550

 

[etudiant]

http://www.europe-solidaire.org/spip.php?article23550

Just to put these levels into perspective, bananas have about 130 Bq/kg, whereas this study notes the seawater is incrementally contaminated up to as much as 0.1 Bq/kg.
Note also that the Hawaii comment refers to the physical damage from large pieces of debris,
not to any putative radioactivity.
There has not been any reports that I've seen about any damage from these debris anywhere in the US.

 

[Borek]

Not to mention fact that the title ("Fukushima radioactive water and tsunami debris spread in the Pacific Ocean") is misleading, as it it can suggest tsunami debris is radioactive as well.

 

[r-j]

Maybe I am wrong, but even if all of the radioactivity from all the reactors spilled into the ocean, by the time it reached America it would be so diluted it wouldn't matter. Right?

 

[seeyouaunty]

Maybe I am wrong, but even if all of the radioactivity from all the reactors spilled into the ocean, by the time it reached America it would be so diluted it wouldn't matter. Right?

Biological life has a habit of concentrating such things up through the food chain.

 

[tsutsuji]

Maybe I am wrong, but even if all of the radioactivity from all the reactors spilled into the ocean, by the time it reached America it would be so diluted it wouldn't matter. Right?

In the following report http://www.irsn.fr/FR/Actualites_pr...ident_Fukushima_sur_milieu_marin_26102011.pdf (October 2011), the French research institute IRSN says that with 27 E15 Bq, the Fukushima sea release is the largest single event of radioactive sea release ever, in the history of mankind. When it will be fully, uniformly diluted into the Pacific Ocean, the Cesium 137 concentration in that ocean will be brought to 0.004 Bq/l . This will be twice the value before the Fukushima accident : 0.002 Bq/l which was caused by the atmospheric atomic weapons tests in the Pacific Ocean in the 1960s. Both values are much lower than the concentration of Potassium 40, a natural radioactive substance, which is 12 Bq/l .

According to http://www.epa.gov/rpdweb00/docs/federal/520-1-88-020.pdf table 2.2 pages 166 and 156, the ingestion dose coefficients of cesium 137 and potassium 40 are respectively 1.35 E-8 Sv/Bq and 5.02 E-9 Sv/Bq. This means that one Becquerel of cesium 137 is 13.5/5= 2.7 times more harmful than one Becquerel of potassium 40 when ingested by a human being.

But 2.7 times 0.004 is still much lower [12/(0.004*2.7)= 1110 times lower ] than 12.

There is also Cesium 134, and it is more harmful (1.98 E-8 Sv/Bq) when ingested, but its quantity was, roughly speaking about the same as Cs 137, and it will decrease with time more quickly than Cs 137 because its half life is about 2 years instead of 30 years for Cs-137.

This half life of 30 years also means that 30 years ago, in 1982, if the IRSN is correct, the Cesium 137 concentration in the Pacific Ocean was 0.002 * 2 = 0.004 Bq/l . So the Pacific Ocean in the 1970s was probably worse than what is expected as a result of Fukushima after full dilution.

By the way, I found a funny comic about how science is reported in the media : http://www.translucid.ca/site/2009/05/22/phd-comics-explaining-the-science-news-cycle/

 

[etudiant]

Biological life has a habit of concentrating such things up through the food chain.

The oceans have much more of the longer lived radiactive materials than humans have.
However, relatively short lived species such as cesium 137 are man made and so they sharply increase the ocean burden of that specific isotope.
The prospect of widespread seafood contamination from Fukushima cesium is nevertheless minimal, simply because the ocean potassium content, about 4 parts per 10,000 of sea water, is enough to swamp the available cesium. Cesium is not preferentially absorbed by the body for mammals or fishes afaik, although there are some fungi that do show a preference for it. Moreover, the body's potassium is in continued flux, so that the half life of absorbed potassium or cesium is about 90 days. The material is not preferentially absorbed or concentrated, unlike iodine for example.

 

[Astronuc]

Investigative reporter Dan Edge wanted to find out what it was like for the workers who were inside the Fukushima Dai-ichi plant when the crisis began. His new Frontline documentary chronicles what happened to those plant engineers, as well as what happened to the small corps of workers who entered the power plant in the days after the disaster.

Freshair - http://www.npr.org/templates/rundowns/rundown.php?prgId=13&prgDate=2-28-2012
Frontline -http://www.pbs.org/wgbh/pages/frontline/japans-nuclear-meltdown/

Some of the technical details are a bit muddled, but nevertheless it is a rather important narrative.

 

[tsutsuji]

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"

Here are my impressions after reading that report :

There are a few obscure statements (in note 5 page 33, they imply that the HPCI "did require electricity" ; page 10 "the revised design-basis tsunami was now 1.4 meters above the seawater pumps" is contradicted by the IAEA mission report which mentions that the seawater pumps had been retrofitted). Perhaps this is inevitable when one summarizes a complex event in a few pages.

Saying on page 10: "As a result, we believe it would be unfair to apportion significant blame for the accident on the actions the operators took (or failed to take) after the tsunami, as the official investigation committee has done", Acton and Hibbs attack and dismiss the Japanese Government's investigation committee's interim report, although they have probably not read it. If they had read it, they would have provided an internet link to the full report rather than to the English summary. The official investigation committee drew its conclusions from the analysis of the facts mentioned in the report. It seems that Acton and Hibbs want to dismiss the Tepco-unfriendly conclusions of the report regardless what the uncomfortable facts might be. Criticizing Tepco must be a sort of taboo in their mind.

The demonstration that the whole world is so much better protected against severe accident than Japan seems to be a little far fetched. That two or 3 plants in such or such country are better protected than Fukushima Daiichi does not mean that those countries as a whole are better than Japan as a whole. After all, Tokai Daini, Fukushima Daini, or Onagawa etc... resisted the tsunami.

The report provides also plenty of examples of weaknesses in countries different from Japan "In many plants in the United States, one expert said, the on-site AC power supply is not stronger than that at Fukushima Daiichi" (page 19). Most French plants lack an alternative heat sink (page 21).

What I disagree most is the way the report flatters the IAEA and extols its supposed virtues.

Page 24: "Nonetheless, given Japan’s participation in the [IAEA tsunami safety] project, it should have been well aware of how far its own practice was lagging behind international standards, and this should have prompted remedial actions." I think this can be understood the other way round. The IAEA should have been aware that Japan was lagging behind, and the IAEA should have distanced itself from Japan and from Tepco. During all these years the IAEA's attitude toward Japan was an attitude of approval. Or where, during all these year, do we find instances of IAEA disapproving Japan and disapproving Tepco ? Isn't the present IAEA president a Japanese ? If Japan was such a bad country, the IAEA should not have elected a Japanese as its president. And the IAEA should not have promoted the November 24-26, 2010 Kashiwazaki international symposium on seismic safety where Tepco's Makoto Takao says in his presentation on "Tsunami Assessment for Nuclear Power Plants in Japan" http://www.jnes.go.jp/seismic-symposium10/presentationdata/3_sessionB/B-11.pdf page 14 "Fukushima Daiichi NPS : we assessed and confirmed the safety of the nuclear plants based on the JSCE method which was published in 2002". If the IAEA had been the paragon of tsunami safety Acton and Hibbs claim it was, the IAEA should have said "This is not good science. We don't want to have anything to do with that. We repudiate the kind of symposium where such approaches can be presented in guise of good science". Instead of that, we find on the IAEA's website at http://www.iaea.org/newscenter/news/2009/lookahead2010.html : "An International Workshop on Seismic Safety of Nuclear Installations will be held in Kashiwazaki in Japan from 17 to 19 March 2010. It is being organised by the IAEA and the International Seismic Safety Centre (ISSC) in co-operation with the IAEA Asia Nuclear Safety Network (ANSN)".

http://www.jnes.go.jp/seismic-symposium10/pictures/images/02opening-001.jpg

Look at the flower bunch. Isn't it cute ? During all these years, the IAEA was in love with Tepco, giving or receiving flowers to it or from it.

http://www.jnes.go.jp/seismic-symposium10/pictures/images/04b-001.jpg

See also Yoko Iwabuchi's presentation http://www.jnes.go.jp/seismic-symposium10/presentationdata/3_sessionB/B-10.pdf about an historical database of tsunamis from 1596 to 2003. This leaves the Jogan tsunami of 869 out.　[1]

http://www.jnes.go.jp/seismic-symposium10/pictures/images/04b-012.jpg
K. Satake was in the room. What was he thinking ?

(All presentations and pictures are available at http://www.jnes.go.jp/seismic-symposium10/presentationdata/content.html )
[1] http://tsunami3.civil.tohoku.ac.jp/ Japan Tsunami Trace Database

 

[zapperzero]

What I disagree most is the way the report flatters the IAEA and extols its supposed virtues.

Page 24: "Nonetheless, given Japan’s participation in the [IAEA tsunami safety] project, it should have been well aware of how far its own practice was lagging behind international standards, and this should have prompted remedial actions." I think this can be understood the other way round. The IAEA should have been aware that Japan was lagging behind, and the IAEA should have distanced itself from Japan and from Tepco. During all these years the IAEA's attitude toward Japan was an attitude of approval. Or where, during all these year, do we find instances of IAEA disapproving Japan and disapproving Tepco ? Isn't the present IAEA president a Japanese ? If Japan was such a bad country, the IAEA should not have elected a Japanese as its president. And the IAEA should not have promoted the November 24-26, 2010 Kashiwazaki international symposium on seismic safety where Tepco's Makoto Takao says in his presentation on "Tsunami Assessment for Nuclear Power Plants in Japan" http://www.jnes.go.jp/seismic-symposium10/presentationdata/3_sessionB/B-11.pdf page 14 "Fukushima Daiichi NPS : we assessed and confirmed the safety of the nuclear plants based on the JSCE method which was published in 2002". If the IAEA had been the paragon of tsunami safety Acton and Hibbs claim it was, the IAEA should have said "This is not good science. We don't want to have anything to do with that. We repudiate the kind of symposium where such approaches can be presented in guise of good science". Instead of that, we find on the IAEA's website at http://www.iaea.org/newscenter/news/2009/lookahead2010.html : "An International Workshop on Seismic Safety of Nuclear Installations will be held in Kashiwazaki in Japan from 17 to 19 March 2010. It is being organised by the IAEA and the International Seismic Safety Centre (ISSC) in co-operation with the IAEA Asia Nuclear Safety Network (ANSN)".

You make a valid and valuable argument. My question to you and the rest of the participants to this discussion is: how to get from being right to doing right? I am quite sure that some political changes are in order (also I think many others here think the same). How can we best start making these changes happen?

I am sure that publicizing the issue, as is already being done here and in a few other places, is a good start. What more can be done?

 

[nikkkom]

You make a valid and valuable argument. My question to you and the rest of the participants to this discussion is: how to get from being right to doing right? I am quite sure that some political changes are in order (also I think many others here think the same). How can we best start making these changes happen?

I am sure that publicizing the issue, as is already being done here and in a few other places, is a good start. What more can be done?

Writing more about the need to upgrade safety of NPPs. All aspects of it: tsunami protection. EDG placement. Flood protection for electrical systems. Addition of totally passive cooling systems. Make personnel know how to use it. Air-mobile rapid response teams for nuclear disasters.

I think it's best if the written material will not focus exclusively on whom to blame, but be more focused on what needs to be done.

If you personally can't write something like this, I'm sure Japan has no dearth of talented journalists.

 

[zapperzero]

http://fukushima.ans.org/

Supposedly has a report on fukushima that I cannot (yet?) access for reason of it being password-protected. Can anyone get to it?

 

[zapperzero]

Writing more about the need to upgrade safety of NPPs. All aspects of it: tsunami protection. EDG placement. Flood protection for electrical systems. Addition of totally passive cooling systems. Make personnel know how to use it. Air-mobile rapid response teams for nuclear disasters.

I think it's best if the written material will not focus exclusively on whom to blame, but be more focused on what needs to be done.

If you personally can't write something like this, I'm sure Japan has no dearth of talented journalists.

I'm sure writing about it in newspapers isn't the be all end all of political action. Any other ideas?

 

[nikkkom]

I'm sure writing about it in newspapers isn't the be all end all of political action. Any other ideas?

Well, Japan is a democratic country. People can protest. They can demand changes in how electricity generation industry is organized, and its unhealthy links with top echelons of politics.

I usually am not very supportive of protesters if they don't have a well-articulated proposal how to make things better. It's easy to be unhappy about something - any kindergarten child can demonstrate that.

Formulating a viable plan how to fix/improve the system is much harder, but it will show people that you are not from kindergarten, that you are a serious and thinking individual, and will likely bring you more supporters. Even some from the opposing camp may actually agree with parts of your proposal, and not fight against you.

 

[zapperzero]

Well, Japan is a democratic country. People can protest. They can demand changes in how electricity generation industry is organized, and its unhealthy links with top echelons of politics.

I usually am not very supportive of protesters if they don't have a well-articulated proposal how to make things better. It's easy to be unhappy about something - any kindergarten child can demonstrate that.

Formulating a viable plan how to fix/improve the system is much harder, but it will show people that you are not from kindergarten, that you are a serious and thinking individual, and will likely bring you more supporters. Even some from the opposing camp may actually agree with parts of your proposal, and not fight against you.

I am sure the same Japanese government that has unilaterally and without consulting the citizenry chosen to both allow TEPCO to hike rates AND to bail them out to the tune of 500 million dollars so far is going to be really amenable to dialogue and implementing well-formulated plans. Wait, I am not.

Also, is it the sole responsibility of citizens of Japan to make sure that no GE Mark 1 BWRs ever go poof again?

 

[Astronuc]

Insiders from the country's nuclear industry described a culture in which regulators looked the other way while the industry put a higher priority on promoting nuclear energy than protecting public safety.

http://www.nytimes.com/2012/03/10/w...pan-ignored-warnings-of-nuclear-disaster.html

That's a fair assessment.

. . . .
One of those whose warnings were ignored was Kunihiko Shimazaki, a retired professor of seismology at the University of Tokyo. Eight years ago, as a member of an influential cabinet office committee on offshore earthquakes in northeastern Japan, Mr. Shimazaki warned that Fukushima’s coast was vulnerable to tsunamis more than twice as tall as the forecasts of up to 17 feet put forth by regulators and Tepco.

Minutes of the meeting on Feb. 19, 2004, show that the government bureaucrats running the committee moved quickly to exclude his views from debate as too speculative and “pending further research.” None of the other 13 academics on the committee objected. Mr. Shimazaki’s warnings were not even mentioned in the committee’s final report two years later. He said the committee did not want to force Tepco to make expensive upgrades at the plant.

. . . .

In 2008, Tepco engineers made three separate sets of calculations that showed that Fukushima Daiichi could be hit by tsunamis as high as 50 feet, according to the company. A Tepco spokesman, Takeo Iwamoto, said Tepco did not tell regulators at NISA for almost a year, and then did not reveal the most alarming calculation, of a 50-foot wave, until March 7 of last year — four days before the tsunami actually struck.

. . . .

 

[Astronuc]

http://fukushima.ans.org/

Supposedly has a report on fukushima that I cannot (yet?) access for reason of it being password-protected. Can anyone get to it?

Try this link - http://fukushima.ans.org/report/Fukushima_report.pdf

If one still has problems, let me know.

 

[zapperzero]

Try this link - http://fukushima.ans.org/report/Fukushima_report.pdf

If one still has problems, let me know.

It's working, thanks. Re-reading it now.
The first skim produced a few impressions:
- these people have never heard of filtered vents
- they have no idea what the media is and they think they can control it

On the plus side, there are many technical suggestions that make very good sense (independent vent paths, improving RCICs by removing dependency on electricity, faster-than-realtime plant simulator for use in emergencies, adding&/improving sensors etc)

 

[nikkkom]

I am sure the same Japanese government that has unilaterally and without consulting the citizenry chosen to both allow TEPCO to hike rates AND to bail them out to the tune of 500 million dollars so far is going to be really amenable to dialogue and implementing well-formulated plans. Wait, I am not.

Also, is it the sole responsibility of citizens of Japan to make sure that no GE Mark 1 BWRs ever go poof again?

After you vented your anger, do you have anything constructive to propose?

 

[zapperzero]

After you vented your anger, do you have anything constructive to propose?

If I had any new and original ideas, I would have presented them. You seem to disfavor even old and unoriginal ones.

 

[Astronuc]

- these people have never heard of filtered vents?

Resolution of Generic Safety Issues: Task CH3: Containment ( NUREG-0933, Main Report with Supplements 1–34 )
http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr0933/sec5/ch3.html

ITEM CH3.2: FILTERED VENTING
This item consists of one recommendation that is evaluated below.

ITEM CH3:2A: FILTERED VENTING
The issue called for the staff to determine whether U.S. containments should be backfitted with filtered vents to mitigate the consequences of severe accidents as is being proposed and implemented in Europe. The Chernobyl accident heightened interest in this issue, though the issue itself has no specific Chernobyl counterpart. The purpose of this issue is to develop information to be used in assessing filtered vents proposed for U.S. reactors and to advise the Commission on whether such systems should be required for specific categories of U.S. reactors. The staff will assess the filtered venting technology emerging from European research and applications for potential U.S. reactor severe accident improvements. This work is a non-distinguishable part of the development of accident management strategies and containment performance assessments.

In pursuing this issue, the staff is expected to increase its knowledge, certainty, and understanding of safety issues in order to increase its confidence in assessing levels of safety. Therefore, the issue considered is to be a licensing issue.

CONCLUSION

Venting is being studied by INEL under staff contracts. This study requires an assessment of European research and applications and keeping abreast of relevant literature and participation in international evaluation activities. One such activity was the Nuclear Energy Senior Group of Experts on Severe Accidents meeting on Filtered Containment Venting Systems held in May 1988 in Paris and the preparation of a "white paper" on the technology and related issues. No separate projects or assessments arising from Chernobyl are envisaged.

Both Westinghouse and AREVA offer Filtered Containment Venting Systems (FCVS)
http://www.westinghousenuclear.com/Products_&_Services/docs/flysheets/NS-IMS-0054.pdf
http://us.areva.com/home/liblocal/docs/Solutions/campaigns/Proven_Solutions/FCVS.html
http://us.areva.com/EN/home-1496/ne...filtered-containment-venting-system-fcvs.html

http://www.oecd-nea.org/nsd/docs/1988/csni88-148.pdf (large file ~ 14.8 MB)
http://www.oecd-nea.org/nsd/docs/1988/csni88-156.pdf

http://sacre.web.psi.ch/ISAMM2009/oecd-sami2001/Papers/p23-Eckart/OECD_H2_Vent_Rev._a3.pdf

 

[etudiant]

Resolution of Generic Safety Issues: Task CH3: Containment ( NUREG-0933, Main Report with Supplements 1–34 )
http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr0933/sec5/ch3.html


Both Westinghouse and AREVA offer Filtered Containment Venting Systems (FCVS)
http://www.westinghousenuclear.com/Products_&_Services/docs/flysheets/NS-IMS-0054.pdf
http://us.areva.com/home/liblocal/docs/Solutions/campaigns/Proven_Solutions/FCVS.html
http://us.areva.com/EN/home-1496/ne...filtered-containment-venting-system-fcvs.html

http://www.oecd-nea.org/nsd/docs/1988/csni88-148.pdf (large file ~ 14.8 MB)
http://www.oecd-nea.org/nsd/docs/1988/csni88-156.pdf

http://sacre.web.psi.ch/ISAMM2009/oecd-sami2001/Papers/p23-Eckart/OECD_H2_Vent_Rev._a3.pdf

These documents apparently date from the mid 1990s and speak of substantial numbers of installations (54 in one case), so it is surprising that the TEPCO plants did not have these.
Were there either passive recombiners or filtered venting facilities at Fukushima that just did not work in the conditions at hand?

 

[rmattila]

Back-fitting old plants with passive filtered venting systems (multi-venturi scrubbing system, MVSS) has one possible complication: if the filtering tank is to be installed indoors (which may be necessary to prevent freezing), there might not be much room for it, so the tank will be rather small. This means adding pressure head to the containment. One should analyze the consequences carefully in order to be sure that the existing low-pressure injection and firewater systems that may be needed in severe accident situations have a sufficient capacity to overcome this additional counter-pressure.