The "more political thread" besides "Japan Earthquake: nuclear plants" scientific one

nikkkom

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

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

http://www.nytimes.com/2012/03/10/wo...-disaster.html

That's a fair assessment.

Astronuc

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

If one still has problems, let me know.

zapperzero

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

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

zapperzero

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

Astronuc

Resolution of Generic Safety Issues: Task CH3: Containment ( NUREG-0933, Main Report with Supplements 1–34 )
http://www.nrc.gov/reading-rm/doc-co.../sec5/ch3.html
Both Westinghouse and AREVA offer Filtered Containment Venting Systems (FCVS)
http://www.westinghousenuclear.com/P...S-IMS-0054.pdf
http://us.areva.com/home/liblocal/do...ions/FCVS.html
http://us.areva.com/EN/home-1496/new...stem-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/oe...nt_Rev._a3.pdf

etudiant

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.

tsutsuji

http://www3.nhk.or.jp/news/genpatsu-...310/index.html The NHK checked the progress of the reinforcement measures listed by the NISA in February, by asking each nuclear plant operator about the 12 points considered "important points", among a list of 30. All plant operators have installed redundant power supplies, including air-cooled generators and power generating trucks. The installations of watertight building doors are completed or under work. The dispersion of the main power distribution panels, meant to lower the risk of a blackout, is difficult to undertake immediately, as finding a suitable location and construction work take time. The installation of batteries able to supply power to instrumentation for a long time is "under study" at all nuclear power plants. Pr. Kazuhiko Kudo of Kyushu university says the government must say clearly which items must be completed before the restart of the plants and which items are allowed to be done later.

The 30 points are probably those mentioned in http://www.meti.go.jp/press/2011/02/...120216004.html "Technical knowledge on the Tokyo Electric Fukushima Daiichi NPP accident (interim compilation)" (16 February 2012) as "Matters being considered which should be reflected in future regulations".

[Countermeasures for external power]
1 Improvement of reliability of external power lines
2 Improvement of earthquake resistance of transformer equipments
3 Improvement of earthquake resistance of switching stations
4 Quick recovery of external power equipments

[Countermeasures for internal electric power equipments]
5 Dispersion of internal electric equipments into different locations
6 Reinforcement of inundation countermeasures
7 Reinforcement of redundancy and diversification of emergency AC power supplies
8 Reinforcement of emergency DC power supplies
9 Installation of separate power supplies for exclusive use
10 Simplification of electric supply from outside
11 Storage of spare items in relation with electric equipments

[Countermeasures for cooling and water injection]
12 Improvement of judgement capacity during an accident
13 Securing inundation resistance and dispersion into different locations of cooling equipments
14 Reinforcement of final heat sink after an accident
15 Improvement of operational reliability of isolation valves and safety relief valves
16 Reinforcement of alternative water injection function
17 Improvement of reliability of cooling and water supplying function of spent fuel pools

[Countermeasures for primary containtment vessel]
18 Diversification of PCV heat removal function
19 Countermeasures to prevent PCV top head flange damage by excess of heat
20 Secured transition to low pressure alternative water injection
21 Improvement of venting reliability and operability
22 Reduction of the environmental impact of venting
23 Secure independance of venting pipes
24 Prevention of hydrogen explosions (concentration management and appropriate release)

[Countermeasures for management and measurement equipments]
25 Equip and secure the command post used during accidents
26 Secure the communication function
27 Secure the reliability of instrumentation during accidents
28 Reinforcement of plant status surveillance function
29 Reinforcement of monitoring function during accidents
30 Building of emergency response system and performance of drills

Underlined items are for boiling water reactors only.

zapperzero

One of TEPCO's theories wrt the explosions is that some of the hydrogen that was supposed to be vented directly via the hardened vents flowed back into the building through the SGTS.
More here, among other places:
http://ajw.asahi.com/article/0311dis...AJ201106040401

EDIT: I do not see how this explains anything, frankly. If hydrogen was supposed to go out from the RPV into the drywell, then wetwell and then via either hardened vent or SGTS into the stack, I cannot understand how it could have entered the reactor buildings instead of flowing back into the wetwell and accumulating there.

zapperzero

NRC transcript from the 17th confirms that US help was refused at least once.

http://pbadupws.nrc.gov/docs/ML1205/ML12052A109.pdf

zapperzero

http://ajw.asahi.com/article/0311dis...imgIX=0&page=1
a writeup of what happened in the Japan PM office and J-gov in general during the first five days

EDIT: It's behind a paywall. Perhaps someone who has a subscription could print it to PDF? For personal archival purposes, of course.

tsutsuji

http://www.lefigaro.fr/sciences/2012...re-inondee.php Interview of Armando Armijo, seismologist at the Paris Institut de physique du Globe.

How was that possible?

tsutsuji

http://www3.nhk.or.jp/news/genpatsu-...20_rokuga.html On 14 March it was found by the Diet's investigation commission that a video showing the then prime minister Naoto Kan visiting Tepco's main office on 15 March 2011 has been recorded. However, the sound and voices were not recorded. According to a commission member, during the 50 minutes when they were busy to respond to the prime minister, the emergency response center was not functioning. According to another commission member it is "strange" that only those 50 minutes are without records of voice. The president of the commission also says "I was surprised" to learn that there is no voice recording.

NUCENG

I am posting a link to an article that discusses the magnitude of the Japanese Disaster from the earthquake and tsunami as compared to the public and media focus on the Fukushima Dai-ichi accident.

We have discussed a lot of aspects of the nuclear issues and politics. In this forum that is totally justified. The article just brings a little balance to the discussion.

http://www.telegraph.co.uk/science/s...Fukushima.html