Althought there is a topic for the earthquake I think a topic completely devoted to the Fukushima incident has its relevancy . There isn't a good summary of basic concepts while it's brand new to most people, news of the tohoku situation are mixed with the nuclear problem , people keep referring to 3rd parties news .

What this topic should include
-I an accessible explanation of the basic concepts :
-II A direct access to the principal source of the information :No more CNN quoting NHK quoting the MEXT . It's quicker and safer to go straight to the source .
-III Studies by legitimate experts in their field: the opinion of a general practitioner on a nuclear plant design is worth @$%^&*!
-IV If possible a careful assessment of the risk level and what you can do

I basic concepts
An explanation of the Fukushima accident
-the now famous Nuclear boy japanese cartoon
with english subs

without

-more down to the earth explanations by MIT
http://tech.mit.edu/V131/N13/yost.html Keith Yost a nuclear engineer from MIT
http://mitnse.com/2011/03/13/modified-ve...inal-post/ Josef Oehmen a mechanical engineer from MIT whose article "why I am not worried about fukushima "went viral .Since that , it has been checked , updated and moved to the MIT blog . While the conclusion of the original article made some bold statements since proved false , the MIT NSE has edited the article so the core explanation can be assumed pretty much sound .


-Radioactivity incident scale http://en.wikipedia.org/wiki/Internation...vent_Scale . Japan and international community ranks Fukushima level 5 . France deems it's a level 6 .
-Radioactivity units and terms
http://hps.org/physicians/documents/phys...rms_V4.ppt
http://www.radiation-scott.org/radsource/2-0.htm
-Radioactivity safety level http://web.mit.edu/newsoffice/1994/safe-0105.html


II Measures
- state of the nuclear reactor : press release of TEPCO
fukushima I http://www.tepco.co.jp/nu/f1-np/press_f1...010-j.html
fukushima II http://www.tepco.co.jp/nu/f2-np/press_f2...010-j.html
- atmospheric radioactivity by prefecture day by day http://atmc.jp/
- tokyo water radioactivity http://www.waterworks.metro.tokyo.jp/pre...index.html
- global measures http://eq.wide.ad.jp/index_en.html

I must point out here that local authorities provide sometimes a better information . Saitama ken for instance has a very complete page : http://www.pref.saitama.lg.jp/page/housyasenryou.html
Feel free to look for your prefecture homepage . I'll include at least all kanto prefecture at some point .

III
- MIT NSE nuclear science and engineering blog http://mitnse.com/
- Health physics society http://hps.org/fukushima/
- CRIIRAD french NGO created in the wake of tchernobyl . http://www.criirad.org/
Unfortunetaly most of the website is in french .
Some part of their press release is available in japanese . Good studies about the food contamination
http://www.criirad.org/actualites/dossie...onais.html
By the way they wish to realise a study of the world atmospheric contamination but are denied access to critical datas :Basically the CTBTO (Comprehensive Nuclear-Test-Ban Treaty Organisation) has a network of 60 stations all over the world designed to detect any secret nuclear test . Incidentally their instruments are so sensitive they can also measure very accuretely the effects of Fukushima worldwide . But they denied any request of access from the CRIIRAD to those data based on the fact they don't belong to the list of the authorized members . Considering most of those organisations are actors of the nuclear industry like the International Atomic Energy Agency it's laughable at best . And so far there wasn't any press release of those datas .
for those of you reading french : http://www.criirad.org/actualites/dossie...et1der.pdf
Creating some buzz for their request/ a facebook page would definetely be a good idea .



IV assesment of the risk level
I don't have any degrees even remotely connected to nuclear physics . I think it would barely qualify as an educated guess . So anything I say should be taken with a grain of salt . You are more than welcome to correct any errors .

1 sievert = 1000 milliSievert (mSv)
1 mSv = 1000 microSievert (μSv)
1 μSv = 1000 nanoSievert (nSv)
1 nSv =1000 picoSievert (pSv)
environemental radioactivity is 2-3mSv a year
general public limit for additional radioactivity is 1 mSv a year
in the water the safety level for an adult is 300 becquerel , for a child is 100 becquerel

25/03/2011
- the situation at Fukushima seems to be moving in the good direction . There is a global agreement of the international community about the fact that Japanese are on the verge of cooling down every reactors and TEPCO press release are encouraging.

- most of the country (south and north) haven't had any effects from fukushima releases so far . The kanto has been clearly hit in the night of the 20 to the 21 . In Kanto every prefecture level radiation level has increased two or threefold . Ibaraki has been the most hit reaching at some point 0.493 microSievert an hour . Since yesterday radiations level have begun dwindling down at a rate of about 1 nanosievert an hour . As of Marth 25th , most japanese prefecture are somewhere around 0.05 microSievert an hour while Kanto's are all above 0.1 .
At any point it has never been anywhere near a radiation sickness level (deterministic effect ) . As for long term cancer effects (stochastic effect) it's arguable but bottom line it's still under the 1mSv a year limit .
However the 1mSv is a global yearly limit so you should also take into account the water and food contamination . Also it may evolve if there are more releases and unfavorable winds .

- The Tokyo tap water which has been heavily scrutinized during the last days is now declared safe even for children . However the radioactivity is clearly on the rise in some part of kanto (decreasing in tokyo but increasing steadily in saitama for instance ) . Besides the japanese governement is clearly using a dummy argument by drawing a parallel with the radiation level of a CT scan (especially considering that new studies show a link between CT scan and cancer . Not that CTscan should be discarded because sometimes there are more risks not performing one but it's a bit of a stretch to say it's safe. So it's a very unfortunate parallel.) . Nobody challenges the fact it won't cause radiation sickness but additionned to the others sources of radiation the long term effects are less obvious .

When I have a doubt my policy is "better safe than sorry " . Personnaly I just try to avoid fresh vegetable and fruit from kanto and stick to mineral water for now .I take some multivitamin , especially D . Based on what I read I don't think there is need for iodine at this level .

it would be nice to have a collection of good links, since they're spread throughout the earthquake thread atm...

here's the links i still check on a daily basis now:
http://eq.wide.ad.jp/index_en.html
All the MEXT readings in one place, in many languages.

http://nettv.gov-online.go.jp/index.html
updates daily with the newest government press conferences. It's in Japanese only, but there are Japanese subtitles for the statements (not the questions though).
(this site is great for a lot of other stuff too, really worthwhile using to learn practical things about life in Japan, science, environment, disaster prevention, etc.)

Collecting links is one of the main points of this topic . I included eqwide in the main topic.

This is a blog by an Engineering professor in applied science and engineering at Chubu University:
http://takedanet.com/

He's been writing on nothing but the nuclear situation since it began, and he and I share a general skepticism of the media situation. He is quite cautious in his perspective.

Edit:
It's entirely written in Japanese

Edit again:
I wanted to add that the definition of Becquerelis very interesting (had to look it up yesterday).
1 Bq = 1 decay event / s

One thing you all need to remember when they talk about Bq on the news is that it is frequently given in "per kg" or "per L" units (per a unit of mass/volume). However, because the density of water is ~1kg/L, 1 Bq/kg ~= 1 Bq/L (when talking about water contamination). So, if someone knows that ACTUAL limits for infants and adults for Bq/L, that would be useful. However, as it is shown above (300 and 100 Bq), it's meaningless.

I woudn`t say that the situation moves in good direction now. It seemed so until yesterday, but then radiation jumped again up to 200 mSv at the site. Seems like fuel rods melted, but at the moment nobody knows for sure where it comes from exactly.
http://headlines.yahoo.co.jp/hl?a=201103...31-yom-sci

One concern I heard voiced recently, but I had not considered previously was the amount of salt left in the reactor. Converting sea water to steam leaves the salt, and this will coat everything. Even if they begin putting new fresh water in there now, it may take a very long time to actually purify the reactor. Also, it would be important to know if the solidified salt could cause problems with cool down of the rods.

Does anyone have any references that discuss the possible implications of sea water in the reactor? of salt on the core? preferably reputable sources of course

I thought the consensus was that pumping the reactors full of salt water will basically trash them making repair not-economically viable.

Yeah, the reactors that had sea water pumped into them are already treated as a complete loss.

nadiatims Wrote:I thought the consensus was that pumping the reactors full of salt water will basically trash them making repair not-economically viable.

Yes, that is the final result. However, in the mean time while fuel is still inside and steam being generated, what is the effect solidified salt? Essentially, it may be clogging up pipes leading to increased pressure/temperature. It also may solidify on partially exposed fuel rods being a thermal barrier for cooling. This is my speculation from a non-nuclear engineering perspective (my expertise is nanoscale thermal transport, which is very different). The Japanese television talk about the effect of sea water on the precision of the device making it useless in the future, but they have made no follow up about the duration of time they've been pumping that stuff in there or what it may do now. What kind of sea water tests have been experimented on for such a scenario before? I haven't yet heard of it being tested and would love to hear of them.

i'm not sure, but i think it may have been tested before. Looking at the pictures, it seems like the seawater was drawn not straight from the sea, but from some kind of enclosed sea pit type things. I think that's why sometimes they couldn't cool it because they had ran dry. If so, it seems like those sea pit things would have been created for that exact purpose. I'm not entirely sure though...

2011/04/12
About an hour ago the NISA (nuclear and industrial safety agency ) has publicly reevaluated the fukushima incident on the INES international nuclear incident scale : it is now rated 7 , the maximum . Although it reads as Chernobyl-like disaster the authority has pointed out that the radioactive matter released is only about a tenth of what chernobyl released .
They published their statement on the NISA website about 10 minutes ago http://kinkyu.nisa.go.jp/kinkyu/2011/04/post-102.html

ghinzdra Wrote:2011/04/12
Although it reads as Chernobyl-like disaster the authority has pointed out that the radioactive matter released is only about a tenth of what chernobyl released .
They published their statement on the NISA website about 10 minutes ago

I just opened my Yahoo page and there was the headline Nuclear incident as bad as Chernobyl. I clicked the link and midway down the page it was acknowledged that the situation is completely different. Unfortunately, most people will just see the headline and panic without actually reading the article.

I m fully aware of this unfortunate phenomenon... Any educated reader knows too well how the media give it all on the headline and although they pretend to inform the public fuel the panic .
More interesting is an alleged statement by TEPCO spokesman Junichi Matsumoto according to which the overall radiaoactive matter released by Fukishma might exceed Chernobyl's . I m not even sure if the news agence is kyodo news or reuteurs but I can't find the statment on the TEPCO website or any statement in japanese for that matter .

ghinzdra Wrote:I m fully aware of this unfortunate phenomenon... Any educated reader knows too well how the media give it all on the headline and although they pretend to inform the public fuel the panic .
More interesting is an alleged statement by TEPCO spokesman Junichi Matsumoto according to which the overall radiaoactive matter released by Fukishma might exceed Chernobyl's . I m not even sure if the news agence is kyodo news or reuteurs but I can't find the statment on the TEPCO website or any statement in japanese for that matter .

Here it is: http://sankei.jp.msn.com/affairs/news/11...027-n1.htm
"In case if 100% of contained radioactivity leaks from the plant, there is a possibility that this will surpass Chernobyl." - he said. The exact status of reactors 1-3 is not clear at the moment (the degree of fuel meltdown, whether pressure vessel also melted or not, whether there are cracks in the concrete containment structures and so on).

A driving tour inside the Fukushima nuclear reactor evacuation zone

[ファブリス]

Quote:Now the Japanese government has moved to crack down on independent reportage and criticism of the government’s policies in the wake of the disaster by deciding what citizens may or may not talk about in public.(...)The government charges that the damage caused by earthquakes and by the nuclear accident are being magnified by irresponsible rumors, and the government must take action for the sake of the public good.

Sounds convenient...

http://japanfocus.org/-Makiko-Segawa/3516

Gulf oil spill one-year anniversary

I like this as a summary of the current situation:
http://www.jaif.or.jp/english/

So far every 2 days there are significant drops in radiation reported at the plant, so the situation seems stable and given more time they'll be able to clean it up even further.

That video from the "dead zone" shows that around 15-20km radius is habitable (around 3μSv/h) at the time of filming and now (2 weeks later) will be even more so. It does suck if you had a nice house around 3km from the plant since now its generally lost and you can't even sell it since its worth next to zero.

I'm all for nuclear energy, just not in the present (outdated in almost every country) form and as long as its done in "reasonable" remote areas. Poland is set to build its first reactors by 2020 and I really hope this incident won't stop that from happening, as long as its something 3rd generation+ there is no need to worry.

Honestly I m a lot less worried about the situation at the nuclear plant /air/water pollution than by food contamination . Contact by skin can't compare to eating something . Unfortunately I can't find much data available about this and it makes thing all the more scary . A chinese friend of mine has left japan and completely changed his professionnal plan based on the food problem . Up now I either resorted to import , kansai product or stock before the incident . But I can't go on like this a lot longer . Import food shop are ripping me off and for some vegetable (like tomatoes), meat/eggs it seems you have to buy from kanto .
Do you guys have any data about food risk level ?

Heatstroke deaths quadruple as nation shuns air conditioners
In my opinion, nuclear energy protesters will be the #1 reason for the expected shattering of the record for heat related deaths this summer. They may as well have broke into elderly people's homes and put a bullet through their heads.

ghinzdra,
I believe that the government works really hard to prevent any potentially dangerous foods from reaching the market. Cases when such attempts fail are rather rare.
However, I woudn`t recommend any seafood from the east coast of Japan (including Chiba).

bodhisamaya Wrote:Heatstroke deaths quadruple as nation shuns air conditioners
In my opinion, nuclear energy protesters will be the #1 reason for the expected shattering of the record for heat related deaths this summer. They may as well have broke into elderly people's homes and put a bullet through their heads.

Are you actually going to blame anti nuclear protestors for the rise in heat deaths? Ill neglect for now the obvious truth that the elderly population hardly care what young anti nuclear protestors think. Instead let's examine that article you gave us. In the first paragraph it says:

"air conditioners were switched off in line with government appeals to curb electricity usage to avoid power blackouts."

This says, in your own given article that the government (and from tepco, too as I have seen in Tokyo) has been asking all of us to stop using AC. Further, I am a grad student at a major university and we began using ac in my lab a few weeks ago, in secret, against the request of the university administration.

Please be careful of throwing the blame on people who don't have anything to do with this tragedy. The blame lies squarely on the negligence that led to I'll prepared nuclear facilities. You can't blame people who protest against the consequences of nuclear power, when this is clearly one of those consequences. Come on, you should know better

Bodhi I take it you're pro-nuclear. I think I'm a bit on the fence about it, not really knowing much about. What do you make of the frequent claims that it is not economically viable without government subsidy/backing? Ie. that it would never emerge in a truly free market.

[Katsuo]

dat5h Wrote:This says, in your own given article that the government (and from tepco, too as I have seen in Tokyo) has been asking all of us to stop using AC.

The leaflet TEPCO put in my letterbox asked that air conditioners be set to a higher level than usual (28º C) and warned against overdoing it due to the danger of heatstroke.

dat5h Wrote:Are you actually going to blame anti nuclear protestors for the rise in heat deaths? Ill neglect for now the obvious truth that the elderly population hardly care what young anti nuclear protestors think.

Are you intentionally trying to not grasp bodhi's meaning, or are you just bad at understanding cause and effect?:

http://rt.com/politics/press/nezavisimay...-power/en/

Quote:The Japanese Ministry of Economy announced yesterday that, due to protests by local authorities in the country, the existing nuclear power plants (NPP) may be shut down, and the country’s power sector will become practically nuclear-free by April 2012.
...
Today, 19 of Japan’s 54 reactors are operational, and the rest have been stopped for inspection and, perhaps, will not be turned on due to a ban by local authorities. If the local governing bodies continue having a negative stance, then by April 2012 all nuclear power generating units will be shut down as a preventative measure, but will not be returned to operational mode.
...
Following the earthquake and tsunami this past March, several other nuclear power plants were shut down in addition to the distressed Fukushima-1 NPP. At the same time, several nuclear power generating units were put out of service for scheduled technical inspections. Due to this situation, Japan now uses only about 36% of its total nuclear capacity.