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View Full Version : Meltdown at Fukushima is worst nuclear accident since Chernobyl



Maciamo
Mar 14, 2011, 22:33
Two more explosions happened at the Fukushima nuclear plant. A meltdown alert has been issued. If things get worse (and there is a good chance that they will), a big part of the population on North-East Japan, and even the Tokyo region, should ideally be evacuated to avoid radiation. It is understandable that the Japanese government has so far denied the necessity to evacuate Tokyo, and will continue to downplay the importance of the nuclear incident to prevent a mass panic. Even if the risk of very harmful radiation is serious, how can a metropolis of 35 million people be reasonably evacuated ? Where would people be going, how would they be transported, where would they stay, for how long, and what would they do ? West Japan cannot become a huge refugee camp for the residents of East Japan. I am sure that the Japanese government is aware of this and prefers to forsake the safety of its people rather to plunging the whole country into chaos and destroying its economy.

Maciamo
Mar 15, 2011, 16:21
A third explosion affecting the last of the three reactors occurred this morning. This re-qualifies the nuclear incident into an accident (level 4) on the International Nuclear and Radiological Event Scale (INES) (http://en.wikipedia.org/wiki/International_Nuclear_Events_Scale). To give you an idea, only two nuclear accidents in history were worse : Chernobyl (level 7) and the Three Mile Island accident in Pennsylvania, USA in 1979 (level 5). Of course it's too soon to tell if it won't degenerate further. I personally don't see how it wouldn't reach at least level 5.

The radiation levels at Fukushima now exceed 8,000 microsieverts per hour, 70,000 times the legal limit of 1,000 microsieverts per annum. If I didn't mistake in my calculations, this equals 2 sieverts per day, or 14 sieverts per week. In terms of radiation poisoning (http://en.wikipedia.org/wiki/Radiation_poisoning), this means that people staying in Fukushima will already suffer nausea and vomiting after half a day, might start having other symptoms like headache, diarrhoea, and fever after one or two days (with a mortality rate of up to 50 percent), and most likely won't survive an exposure of more than 3 days.

The big question now is how far away from Fukushima does it become safe ? Chernobyl left a no-man's land in a 100 km radius, with fallout landing on a 300 km stretch to the north-east (Russia-Belarus border - see map (http://en.wikipedia.org/wiki/File:Chernobyl_radiation_map_1996.svg)). The nuclear plant is actyally located in Okuma, 75 km south-east of Fukushima city. It might be necessary to evacuate at least the region of Sendai, Aizu-Wakamatsu and Shirakawa, which are all in a 100 km radius. Tokyo is 250 km away.

Maciamo
Mar 15, 2011, 18:20
The BBC just posted a Q&A: Health effects of radiation exposure (http://www.bbc.co.uk/news/health-12722435).

Maciamo
Mar 15, 2011, 22:45
The BBC now reports (http://www.bbc.co.uk/news/world-12740843) that radiation dosages of up to 400 millisieverts (0.4 Sv) per hour were recorded at the site. That is 50 times more than yesterday. According to the World Nuclear Association, exposure to over 100 millisieverts a year is a level which can lead to cancer. People near the nuclear plant get this amount of radiations in just 15 minutes. At such level, people would receive a lethal dose of 8 sieverts if continually exposed for 20 hours. In other words, anybody staying on the site today has a death sentence (although it can take months or years to die from radiation exposure).

As I expected this morning, the gravity of the meltdown has been revised to level 6 (Serious Accident) on the INES scale of 7. This makes it only one step away from Chernobyl and more serious than the Three Mile Island accident.

Radioactivity levels in Tokyo are currently 10 times higher than normal. This shouldn't pose a health risk if things do not deteriorate. The winds are now blowing towards the Pacific Ocean. A change of direction towards Tokyo would, however, inevitably increase the risk of radiation in the capital.

It has been predicted that rain clouds could spread radiation around Japan and in other countries in the region. The main concern about this scenario is that contaminated rain water would cause rivers, water tables and agricultural products to become radioactive, possibly for many years. It is lucky that the earthquake didn't take place during the summer monsoon. A typhoon would have spread the radioactivity to dramatic proportions.

obione46
Mar 18, 2011, 12:28
I'd suggest you go to the english version of tokyo denryoku..they give a daily update...also I understand the japanese minister of health has increased the max load of radatiation that one can be exposed to? and using helicopters, what a waste of time..they should position a fire engine pump truck. and pump seawater in to the reactor's cooling chamber.. fire engine pumps have high capacity pumping availabilty, which they can use untile the new power source is connected...

Maciamo
Mar 27, 2011, 15:45
The situation is deteriorating again. Just as we thought things were slowly getting under control, the radioactivity have soared to the unprecedented level of 1000 millisieverts per hour, i.e. 10 million times the usual level (http://www.bbc.co.uk/news/world-asia-pacific-12872707). This means that up to 5 percent of the workers at the plant will die within a month by staying one hour on the spot, 50 percent won't survive an exposure of more than 2 hours, and nobody could survive 8 hours of radiation at that level and would succumb in a matter of hours.

In comparison, the criterion for relocation after Chernobyl (http://www.climateactioncentre.org/Fukushima-radiation-levels-compared) was 350 millisieverts in one's lifetime, the dose received by workers at Fukushima in only 20 minutes.

This all is extremely worrying. Yesterday we learned that the sea along the Pacific coast of Japan was 1,250 times more radioactive than normal. In my opinion, this news is worse than the forced evacuation of the Fukushima prefecture because Japanese diet is highly dependent on fish and seafood from its Pacific coast (one of the richest region for fishing in the world). I foresee that thousands of fish shops and restaurants will go bankrupt in the coming months due to justifiable fears about radioactive fish. Fish and seafood go well beyond sushi in Japanese cuisine (http://www.wa-pedia.com/culture/japanese_food.shtml). It isn't by chance than the Tsukiji (http://www.wa-pedia.com/japan-guide/tsukiji.shtml) is the world's largest fish market. Knowing that there are over 200,000 restaurants in Tokyo, this would be a heavy blow to the Japanese economy, notwithstanding the fact that the price of meat will skyrocket to compensate for fish and seafood.

The economic consequences of prolonged radioactive fisheries might be as serious as the cost of the tsunami itself. Today's announcement that radiations were now 125 times higher than on 15 March (the day after the meltdown started) is bad omen for the long-term radioactivity in the sea (another good reason never to locate a nuclear plant by the sea !). Agricultural products from the Fukushima prefecture are already compromised for many years, if not decades.

But the first concern for many Japanese in the region of Tokyo and Sendai at the moment will be about their own safety. The USA recommended an evacuation zone in a radius of 80 km (which is less than Chernobyl). It would make sense to extend this radius in consideration of the escalating radioactivity. Chernobyl had an evacuation radius ranging from 100 to 400 km and children are still born with terrible malformations nowadays (http://en.wikipedia.org/wiki/Chernobyl_disaster#Assessing_the_disaster.27s_effe cts_on_human_health), 25 years later, in spite of that. It clearly wasn't enough. Back then, the USSR had decided that the evacuation zone stopped just before Kiev and Minsk (http://en.wikipedia.org/wiki/File:Chernobyl_radiation_map_1996.svg). This was obviously an easy way of not having to relocate millions of people. It is exactly the approach taken by the Japanese authorities at present.

The Japanese government will always prefer to "sacrifice" part of its population to diseases on the long run rather than cause an immediate panic and costly mass relocation. Their logic, in the long tradition of Japanese politicians, is that the people in office now won't have to deal with the medical consequences on the population in 10 or 20 years' time, because they will most likely have retired by then. This approach has been consistently adopted by post-war Japanese politicians for every single kind of problem the country has faced, from ecological disasters (like Minamata (http://en.wikipedia.org/wiki/Four_Big_Pollution_Diseases_of_Japan)) to economic plight. This is why I personally wouldn't stay in Sendai and couldn't be truthful by telling people the area is still safe.

Maciamo
Mar 28, 2011, 16:47
Tepco has announced that the radiation level was not 10 million times higher than normal, but 100,000 times. The Japanese government has criticised their mistake as "absolutely unforgivable". However it seems that the number of millisieverts was correct (1000 mSv), so I don't see what the fuss is all about. They just took the wrong reference for the "normal radiation" level. The fact is that there is no "normal". Firstly, radioactivity varies widely between regions. Then, the radioactivity at a nuclear plant varies even more depending on whether you measure it inside or outside the plant, or a few kilometres away. My point is that "normal" is a fuzzy concept because there isn't just one normal, and the data can be easily tweaked to suit one's interests. I wouldn't be surprised if Tepco was coerced by the government to revise its announcement in order to calm the population after the stir the original announcement made.

Maciamo
Mar 29, 2011, 03:24
More bad news from Fukushima.

Plutonium was found leaking from the nuclear plant.

Here is what Reuters reported (http://www.reuters.com/article/2011/03/28/us-japan-quake-idUSTRE72A0SS20110328).


In a briefing around midnight in Tokyo, the vice-president of under-pressure TEPCO apologized for making people even more worried with the announcement -- but stressed the traces of plutonium 238, 239 and 240 were not dangerous.

"Plutonium found this time is at a similar level seen in soil in a regular environment and it's not at the level that's harmful to human health," Sakae Muto told reporters.

More lies and deceptions. How can plutonium 238, 239 and 240 be present in soil in a regular environment since they are all man-made elements. Only plutonium-244 exists naturally on Earth, but at such infinitesimal levels that there is no way it can compare with what was found at Fukushima-Daiichi. Do they really take people for idiots ?

And on top of that they claim that the level of plutonium detected was not harmful to health. What newsworthy, nuclear-incident-related level of plutonium is not harmful to health ? Plutonium is about the most harmful radioactive element there is. Contrarily to iodine, which "only" causes thyroid cancer (one of the most treatable cancer), plutonium is absorbed by the bones and liver, causing two of the most deadly and painful kinds of cancer. If that wasn't bas enough, plutonium-239 has a half life of 24,000 years, which means, as anyone who has been to secondary school knows, that its present level of radioactivity will only have halved in 24,000 years. In comparison, iodine has a half-life raging from a few hours to two months, depending on the isotope. Put differently, if only iodine had contaminated the region, it would be safe to live there fairly quickly. If plutonium has been released in the environment, the area is pretty much condemned forever. I am flabbergasted at how Tepco can downplay the gravity of the situation like this. What credibility have they got left ?

Maciamo
Mar 31, 2011, 16:19
The UN's International Atomic Energy Agency is recommending to extend the evacuation zone radius after recording radiation levels exceeding the safety limits in Iitate, a village 40km north-west from the plant. I personally maintain that a 40 km radius is not enough, and that a wider radius of 80 to 100 km should be seriously considered. Iitate lies 2/3 of the way from Futaba (where the Fukushima-1 nuclear plant is located) and Fukushima city (http://en.wikipedia.org/wiki/Fukushima,_Fukushima), the prefectural capital, where 300,000 people live.

Maciamo
Apr 12, 2011, 16:29
One month after the meltdown, Japan finally raises the nuclear crisis level to 7 (http://www.bbc.co.uk/news/world-asia-pacific-13045341), the highest level on the INES scale. This makes it as serious a nuclear accident as Chernobyl, despite the lower amount of total radiation emitted so far in Fukushima. This is essentially what I had been saying only 2 days after the tsunami.

Maciamo
Aug 23, 2011, 15:18
The TIME just posted a new article about the Fukushima nuclear accident : Nuclear Exclusion Zones Arise Around Fukushima (http://ecocentric.blogs.time.com/2011/08/22/an-nuclear-exclusion-zones-arises-around-fukushima/)

As I suspected just a few days after the tsunami, the area will be uninhabitable for many years :


Today the Japanese government reported that higher than expected levels of radioactive contamination may keep areas around the Fukushima nuclear plant off-limits for human habitation for years, or even decades.
...
The 90,000 residents who live within a 12.4 mile (20 km) radius of the stricken plant—nearly all of whom have been homeless for more than five months—are likely to be a lot sorrier. Government data shows that some areas within the evacuation zone are contaminated with the radiation equivalent of more than 500 millisieverts a year—25 times higher than Tokyo's safety limit for annual exposure. Even if TEPCO can completely halt the leakage of radiation from the plant, those levels mean that thousands of homes may remain too contaminated to live in for years or decades, as the case has been with the exclusion zone that now surrounds the Chernobyl plant in Ukraine.

Maciamo
Sep 9, 2011, 18:40
Nature's website (http://blogs.nature.com/news/2011/09/directly_comparing_fukushima_t.html?WT.mc_id=TWT_N atureNews) provides a map comparing the radioactive fallout of caesium-137 of Fukushima with those of Chernobyl. As you can see the intensity level was similar, but the area affected by the fallout was much wider in Chernobyl (probably because it is a falt landlocked region, as opposed to a mountainous coastal area for Fukushima).

Maciamo
Oct 26, 2011, 03:42
A new international study (http://www.nature.com/news/2011/251011/full/478435a.html) (Stohl, A. et al.) has now confirmed that the Fukushima fallout was far worse than the Japanese government ever admitted.

Minty
Jan 25, 2012, 03:40
I actually know a japanphile who went to sendai for his internship, and do you know what he said, he said that for his robotic engineer studies Japan was the "ONLY" country who had advance technology in robotic engineer. :silly::eek:

Maciamo
Jan 26, 2012, 16:55
I actually know a japanphile who went to sendai for his internship, and do you know what he said, he said that for his robotic engineer studies Japan was the "ONLY" country who had advance technology in robotic engineer. :silly::eek:

Japan is indeed the most advanced country when it comes to robotics - one of the few fields in which it is still a global leader.

Minty
Jan 27, 2012, 11:47
Japan is indeed the most advanced country when it comes to robotics - one of the few fields in which it is still a global leader.

You are missing the point. The ONLY country out there to do your internship because you are a robotic engineer student ???? He did it last summer, very close to the nuclear accident. Even if you career is important shouldn't you be concern about your health first???

His share mate will do it in Scandinavia. He said that they paid engineers better than in France.

Maciamo
Jan 27, 2012, 17:11
You are missing the point. The ONLY country out there to do your internship because you are a robotic engineer student ???? He did it last summer, very close to the nuclear accident. Even if you career is important shouldn't you be concern about your health first???

His share mate will do it in Scandinavia. He said that they paid engineers better than in France.

Even if Japan is the only country, Sendai is not the only city. He just should have asked to go to another city claiming radiation fears.