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Post by edireland on Aug 30, 2013 21:11:51 GMT 9.5
200kBq/L? They lost ~300kL. That means they lost something in the region of 60GBq. The specific activity of 137Cs is something like 814GBq/g.
Which means they lost something like 70 milligrammes of Caesium-137 equivalent.
So they haven't really very much at all, this is the problem with the Becquerel, it is such a tiny unit that you always end up with huge numbers.
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Post by cyrilr on Aug 31, 2013 20:57:56 GMT 9.5
Sod, the 300 tonnes did not leak into the sea. That's an important fact you're incapable of comprehending.
Here is what Sod forgot to quote:
Further inland, nearer to the faulty tank, there was no detected caesium while beta radiation was at 93 Bq/L. This compares to some 200,000 Bq/L in water sampled from the faulty tank, indicating this is not reaching the sea in any significant quantity, if at all.
And in fact, Sod, even if all of the radioactive water would reach the sea, its impact to the environment would be negligible. The stuff just gets diluted into the sea, which has vastly more radioactivity in it from natural background sources such as K-40, even compared to all of the radioactivity in the Fukushima contaminated water combined.
There is no risk here. No one has died or even got injured. No one will die from these leaks. It is hyperbole.
@ the moderator of this forum. Is hyperbole without fact or science such as what Sod displays allowed as per forum policy?
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Post by sod on Sept 1, 2013 7:32:57 GMT 9.5
Sod, the 300 tonnes did not leak into the sea. That's an important fact you're incapable of comprehending. Here is what Sod forgot to quote: Further inland, nearer to the faulty tank, there was no detected caesium while beta radiation was at 93 Bq/L. This compares to some 200,000 Bq/L in water sampled from the faulty tank, indicating this is not reaching the sea in any significant quantity, if at all. And in fact, Sod, even if all of the radioactive water would reach the sea, its impact to the environment would be negligible. The stuff just gets diluted into the sea, which has vastly more radioactivity in it from natural background sources such as K-40, even compared to all of the radioactivity in the Fukushima contaminated water combined. There is no risk here. No one has died or even got injured. No one will die from these leaks. It is hyperbole. @ the moderator of this forum. Is hyperbole without fact or science such as what Sod displays allowed as per forum policy? I did not claim, that the water leaked into the sea. And i am actually not really worried about it leaking into the sea that much. We know that water was leaking. But TEPCO can not even say how much. (most likely it is 300 tons, i provided the links above) Soil got contaminated and there were puddles of water with significant radioactive contamination. What happened to the rest, we don t know. I am actually more concerned about ground water contamination, than about sea water. But i have serious doubts over your approach to "dillution" in the sea. the radioactive material does not get perfectly dilluted in a near endless ocean, but instead it might get concentrated at some places and it also might bioaccumulate. This is a cause of concern in Japan and is causing serious damage to the Fukushima fishermen. This is not a problem made up by me, but it is shared by many others. www.japantimes.co.jp/news/2013/08/30/national/fukushima-fishermen-cant-catch-a-break/#.UiJnED9rmJA--------------------------------- I actually do not think that anyone will die from this particular leak. And to claim that somebody did, would indeed be hyperbole. But i did not make this claim. on the other hand, TEPCO is having such little control, that they cannot even tell, how much water leaked. And i actually think that it is at least close to hyperbole to claim, that the unknown amount of nuclear material released from the Fukushima plant could never kill or injury a single person.
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Post by sod on Sept 2, 2013 9:27:39 GMT 9.5
While we are having this discussion, TEPCO has suffered additional leaks which could have easily dealt a lethal dose to a worker: www.japantimes.co.jp/news/2013/09/01/national/tepco-reports-leaking-pipe-four-hot-spots/#.UiPS5z9rmJA"The discovery of the dripping pipe came just after Tepco said late Saturday it had found hot spots at four sites near the water tanks, with one giving off 1.8 sieverts per hour — enough to kill a human being in four hours." TEPCO has used cheap material to store this waste. Do you really think they should not be punished?
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Post by sod on Sept 2, 2013 9:33:01 GMT 9.5
There is no risk here. No one has died or even got injured. No one will die from these leaks. It is hyperbole. Do you really stand by that claim? Here is, what the Guardian says: "Tepco admitted recently that only two workers had initially been assigned to check more than 1,000 storage tanks on the site. Neither of the workers carried dosimeters to measure their exposure to radiation, and some inspections had not been properly recorded."
www.theguardian.com/environment/2013/sep/01/fukushima-radiation-levels-higher-japan so workers without dosimeters are walking around in an environment, which could kill them in 4 hours. And we will simply not know, what happened to them. Because TEPCO doesn t keep records...
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Post by achaios on Sept 3, 2013 7:14:00 GMT 9.5
www.tepco.co.jp/en/announcements/2013/1230191_5502.htmlsummary: beta radiation at 5cm above ground = 1,800 mSv/h beta radiation at 50cm above ground = 15 mSv/h. gamma radiation measured = 1 mSv/h. Can all this beta penetrate the worker's boots when it can't penetrate 50 cm of air?
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Post by edireland on Sept 3, 2013 7:44:39 GMT 9.5
Essentially a decent pair of waterproof boots will provide almost complete protection from the spill.
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Post by quokka on Sept 3, 2013 15:31:08 GMT 9.5
Now the regulator thinks they may have been a bit hasty in declaring an INES 3 event and may have to downgrade. They are turning this into a communications disaster. All they have to do is be level headed, factually correct as far as is reasonably possible and clearly explain the significance any event together with any safety implications it may or may not have. This kind of thing is hardly confidence building. Fukushima Watch: Authority Chairman Not Convinced Level 3 Needed
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Post by sod on Sept 3, 2013 19:41:23 GMT 9.5
Essentially a decent pair of waterproof boots will provide almost complete protection from the spill. So when you folks say "there is no risk", you basically mean "there is no risk, if you carry the right protective gear"
and under these circumstances neither natural disaters (fire and smoke wont hurt you with the right protective gear), nor any substance (basically all poisons will be stopped by the right protective gear) carries any "risk" any longer! As the"watchmen" were not carrying dosimeters, we simply don t know, whether they spent time sitting next to the spill or not. Boots also do not protect against inhalation of beta radiating particles, or do they?
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Post by sod on Sept 3, 2013 19:53:45 GMT 9.5
Now the regulator thinks they may have been a bit hasty in declaring an INES 3 event and may have to downgrade. They are turning this into a communications disaster. All they have to do is be level headed, factually correct as far as is reasonably possible and clearly explain the significance any event together with any safety implications it may or may not have. This kind of thing is hardly confidence building. Fukushima Watch: Authority Chairman Not Convinced Level 3 NeededThey lost an unknown amount of contaminated water, most likely 300 tons, possibly more. A significantly smaller release at Sellafield was also put into category 3. Tanaka is building a reputation of being rather uncritical towards the industry. This is very bad for a watchdog and it is the reason that caused the Fukushima accident in the beginning. The public is watching the response of TEPCO and the japanese government to the continuous accident at the Fukushima ruin. This editorial gives a very good view, of what people expect: mainichi.jp/english/english/perspectives/news/20130903p2a00m0na013000c.htmlIt is just completely unclear, why the government and that for the people should pay for the ice wall at Fukushima: www.bbc.co.uk/news/world-asia-23940214
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Post by David B. Benson on Sept 4, 2013 8:35:46 GMT 9.5
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Post by quokka on Sept 4, 2013 10:20:39 GMT 9.5
It is just completely unclear, why the government and that for the people should pay for the ice wall at Fukushima: Yes, lets really get hung up on the expenditure of less than $4 dollars per head of population.
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Post by edireland on Sept 4, 2013 10:26:18 GMT 9.5
Why should the government or the people pay for the collosal subsidies provided to every alternative?
And these things sound expensive but aren't really expensive per kWh of electricity produced by nuclear in Japan over the last 60 years.
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Post by quokka on Sept 4, 2013 12:09:44 GMT 9.5
According to IEA stats, in a single year - 2009 - nuclear power in Japan produced 279,750 GWh of electricity that would otherwise have been produced by burning fossil fuels. If we take a ballpark figure of $0.05/kWh as the average external cost of fossil fuels, then nuclear power avoided nearly $14 billion dollars of the external costs of fossil fuels. And that's just for one year.
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Post by Roger Clifton on Sept 4, 2013 12:56:33 GMT 9.5
Thanks for the link, DBB. At last we have a respected radiation health expert giving us a threshold dose for human safety: 100 mSv. To quote it... 'Gerry Thomas of Imperial College, London said, "We have lots of information from studies where high doses of radiation have been used to treat cancer, but have found that the lowest dose of radiation that we can see health effects of radiation exposure, such as increased cancer incidence, is 100 millisieverts." Earlier...'Professor Gerry Thomas is Chair in Molecular Pathology at Imperial College, London and an expert in radiation impact. ' What is not clear (to me) is the period short of which that accumulated dose is dangerous, and longer than which the implied dose rate is low enough for the human body to shake off any effects before they accumulate.
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Post by edireland on Sept 4, 2013 22:57:51 GMT 9.5
Also I am pretty sure you can't use ordinary LD50 doses when your dose is being concentrated itno the bottom 50cm of your body.
Unless you are suggesting that the workers will strip off and then start wallowing in a strange pool of water in the middle of the plant.
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Post by David B. Benson on Sept 5, 2013 8:51:23 GMT 9.5
Roger Clifton --- The 100 mSv dose is for high dose rate, as in X-rays, etc. I currently know of no directly done studies on dose rate limits. The closest I have read is probably by Wade Allison and reads The result is that new safety levels for human radiation exposures are suggested: 100 millisievert in a single dose; 100 millisiever t in total in any month; 5,000 millisievert as a total whole-of-life exposure. These figures are conservative, and may be debatable within factors of two, but not ten
I encourage those interested in radiation safety to visit his website.
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Post by sod on Sept 10, 2013 4:34:48 GMT 9.5
Nobody at TEPCO will be punished: ajw.asahi.com/article/behind_news/social_affairs/AJ201309090099The nuclear industry will not have to face any responsibility for the disaster caused by their sloppy safety measures. This will help TEPCO in the short run, but will massively damage the nuclear industry. Your discussion of safety levels does the same. You are sending a clear message to the people: "nuclear power will talk about strict safety levels, until they have a problem. Then they will ignore all levels set" The same is true for the release of water to the sea. People were told that nuclear waste is not a problem and that nuclear power plants do not release significant amounts of contaminated material into the environment. Now they learn that the solution to accumulating contaminated water is a simple release into the sea. They will remember this, when a nuclear plant close to them wants to get back online. The people of Japan are not happy with this crisis: ajw.asahi.com/article/behind_news/social_affairs/AJ201309090099
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Post by David B. Benson on Sept 12, 2013 14:04:43 GMT 9.5
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Post by Jane Jackson on Sept 13, 2013 14:21:45 GMT 9.5
Why didn't TEPCO bury Fukushima's reactors in leaded sand, as was done at Chernobyl?
I ask this question because my colleague, who has a PhD in physics, wrote recently: ------------------------- 2.5 years - or 1000 days - after 3 of 6 of Fukushima's nuclear reactors melted, 3 radioactive cores are cooled daily by 300 tons of water. Popping like 1000 giant highly radioactive mushrooms, 1000 tanks filled with 300 tons of radioactive water crowd the plant, with one added each day. At least 3 tanks leak, one leaches 1.8 Sv/hr - the equivalent of 100,000 chest X-rays per hour, or 1000 CT scans each hour.
Soviets buried Chernobyl's reactor in 4500 tons of leaded sand within 4 days by helicopter, added a cooling barrier underneath in 10 days, and a sarcophagus in 5 months in 1986.
In 2013, we CAN be better than this!
They should have asked for help from those who had gone through it before. ... They have to encase the 3 cores and the 5 spent fuel pools in leaded silica (sands melt into silica on the hot cores) before it is too late - ASAP! ------------------------
Can an expert please comment on this PhD physicist's statement?
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Post by quokka on Sept 13, 2013 15:48:30 GMT 9.5
Jane Jackson,
I don't claim to be an expert, and have but a lowly BSc with physics major, but I must say that anybody penning the following sentence, and implying some sort of authority or expertise, needs to go back to school and get their SI units right
At least 3 tanks leak, one leaches 1.8 Sv/hr - the equivalent of 100,000 chest X-rays per hour, or 1000 CT scans each hour
The correct unit for quantifying radiation leaks is the Becquerel and the rate of release is Becquerel per unit time. That should be accompanied by analysis of the various radionuclides present in the leak. 1.8 Sv/hr is quite meaningless.
As for dumping a whole lot of stuff on top of the damaged reactors, at Chernobyl the reactor containment was destroyed and the core open to the atmosphere. It was streaming radioactive materials into the atmosphere. Various materials were dumped on it to contain that and put out fires.
At Fukushima the situation is very different. The reactor containment is basically intact and no fires. There is essentially no release into the atmosphere.
The quoted paragraphs reek of fear mongering and little else.
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Post by Ed Leaver on Sept 13, 2013 23:33:45 GMT 9.5
Quokka: As a minor point, Bq and Sv are both legitimate units of radiation measure. One can't fault sod for using and not understanding Bq, and fault Jane and her physics friend for *not* using and understanding Bq. In fact, Sv is the more meaningful unit in terms of hazard of human exposure, as it accounts for (substantial) differences between alpha, beta, and gamma radiation, and the particular energy of each. Basically, one Bq is one radioactive decay of anything, by any means (alpha, beta, and/or gamma) per second. Its certainly useful in its own context, but not as useful as Sv in terms of human hazard. Jane: probably the most objective description of either Fukushima or Chernobyl may be found at World Nuclear Association's website, under their Information Library. Safety of Plants. Their entire library is chock full of information on all aspects nuclear, is highly readable, and well worth the browse. WNA often gets dismissed as an "industry forum" and therefore biased and unreliable. I've personally found it by far the most reliable, and as for bias, while I can't say there is none whatsoever, its certainly far less than what I've seen elsewhere. But yes, as Quokka said, Chernobyl is so vastly different from Fukushima that comparison on any aspect other than radiation release to the surrounding area outside the plant site (what you and I and most other folks are most interested in and affected by), is pretty much meaningless. Both are covered at WNA. Their site for recent news is World Nuclear News. Again not super-technical, articles are meant for all.Thanks.
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Post by grlcowan on Sept 14, 2013 0:03:58 GMT 9.5
... Sv is the more meaningful unit in terms of hazard of human exposure, as it accounts for (substantial) differences between alpha, beta, and gamma radiation, and the particular energy of each. The most useful unit of ionizing radioactivity -- although it doesn't capture quite the entirety of the range of variation of biological effectiveness -- is the watt. TEPCO's use of sieverts was very misleading. Eventually they expanded on it -- This implies very low-energy beta rays that were mostly unable to penetrate 45 cm of air, and thus also unable to penetrate clothing and skin. So the bruited possibility of a lethal dose in a few hours did not actually exist. One should not naively assume that any error TEPCO makes is in the direction of favouring nuclear energy. Government personnel are sometimes dropped, as if from heaven, into TEPCO positions, and the Japanese government is clearing a half-billion-dollar windfall, if its natural gas taxation rates are typical, every month it finds plausible reasons to keep most of Japan's citizens' nuclear power stations shut down.
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Post by Ed Leaver on Sept 14, 2013 0:25:57 GMT 9.5
... Sv is the more meaningful unit in terms of hazard of human exposure, as it accounts for (substantial) differences between alpha, beta, and gamma radiation, and the particular energy of each. The most useful unit of ionizing radioactivity -- although it doesn't capture quite the entirety of the range of variation of biological effectiveness -- is the watt. TEPCO's use of sieverts was very misleading. Eventually they expanded on it -- This implies very low-energy beta rays that were mostly unable to penetrate 45 cm of air, and thus also unable to penetrate clothing and skin. So the bruited possibility of a lethal dose in a few hours did not actually exist. Thanks for the expansion link, grlcowan. The watt is the fundamental SI unit of power, energy expended per unit of time. 1 W = 1 Joule/sec. Whether it is most useful unit of ionizing radioactivity depends entirely upon the context within it is used. In general, the Seivert (Sv) is most useful for biological effect. But that too is context dependent. Most effect tables and numbers e.g. "100 mSv -- Lowest level at which increase in cancer risk is evident" assume whole-body dose, which as you and your helpful link point out, does not really apply in this particular case. There are big differences between alpha, beta, and gamma radiation in terms of penetrability. See Nuclear Radiation and Health Effects.
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Post by quokka on Sept 14, 2013 12:21:34 GMT 9.5
The point about units is that dose rate at various points within the Fukushima Daiichi plant is of primary interest as a matter of industrial safety at the plant. And of course as an indicator of a potential issue if high dose rate is newly detected at some location. As an indicator of release of radioactive materials into the broader environment it is quite meaningless. However that is just the way it is being used by certain parties for their own purposes. Headlines scream: "Radiation jumps 18 times at Fukushima". The Pacific is becoming full of radioactive fish and similar such drivel.
Using dose rates at selective points within the plant as an argument for entombment is just scaremongering nonsense, and unbecoming for somebody who claims to be a physics PhD. If worker exposure was unmanageable and at dangerous levels there of course might be a case. But it isn't. If there was large scale, ongoing and unmanageable radiation release into the broader environment there also might be a case. But that isn't happening either.
The proper use of units becomes very important in this context.
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Post by Jane Jackson on Sept 14, 2013 18:18:04 GMT 9.5
Jane: probably the most objective description of either Fukushima or Chernobyl may be found at World Nuclear Association's website, under their Information Library. Safety of Plants. Their entire library is chock full of information on all aspects nuclear, is highly readable, and well worth the browse. WNA often gets dismissed as an "industry forum" and therefore biased and unreliable. I've personally found it by far the most reliable, and as for bias, while I can't say there is none whatsoever, its certainly far less than what I've seen elsewhere. But yes, as Quokka said, Chernobyl is so vastly different from Fukushima that comparison on any aspect other than radiation release to the surrounding area outside the plant site (what you and I and most other folks are most interested in and affected by), is pretty much meaningless. Both are covered at WNA. Their site for recent news is World Nuclear News. Again not super-technical, articles are meant for all.Thanks.Thank YOU! This is very helpful. I have just spent four hours reading articles on these two webpages and their links. I now understand. I will try to summarize it for my colleague.
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Post by sod on Sept 21, 2013 5:39:13 GMT 9.5
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Post by edireland on Sept 21, 2013 20:35:14 GMT 9.5
They won't have to.
They will be required to by the Japanese government.
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Post by quokka on Sept 25, 2013 1:10:15 GMT 9.5
The Japan Nuclear regulation Authority has released results of sea water monitoring from the seas off Fukushima, Miyagi and Ibaraki prefectures. Sea Area Monitoring - September 17 2013In all cases, the concentration of radio isotopes attributable to release from the plant are either trivial or beneath the level of detection. The gulf between reality and media fueled frenzy of supposed massive release of radioactive materials is vast. Some people have made fools of themselves.
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Post by Ed Leaver on Sept 28, 2013 8:10:27 GMT 9.5
The gulf between reality and media fueled frenzy of supposed massive release of radioactive materials is vast. Some people have made fools of themselves. Oddly enough, Slate (of all sites) ran this piece this morning: Fukushima’s Worst-Case Scenarios: Much of what you’ve heard about the nuclear accident is wrong
Perhaps Slate ran it because the material had to be coaxed from the U.S. government under an FOIA request. Or perhaps its because (by sheerist coincidence) IPCC released AR5 this morning and Slate still has an editor or two who remains a closet realist.
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