Evacuation Policy Versus Radiation Level Measurements In Japan
March 18th, 2012
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Here are some of the latest measurements of radiation levels in the Fukushima region of Japan, these were made just last month.
There is something very striking about this image even at first glance. Notice that the no-entry zone has absolutely no correspondence whatsoever to radiation levels. It’s simply a circle drawn around the nuclear plant. Much of the area has quite low radiation levels and some of the area outside the exclusion zone has higher radiation levels than the area within it. Since there’s now no real danger of the reactors being further damaged or experiencing uncontrolled discharges, there’s absolutely no reason to enforce a no-entry zone based on such a blind method of drawing the map. If a no-entry zone is to exist at all (which it really, at this point, does not need to)
Actual Doses experienced:
Few areas exceed 20 uSv per hour by very much. The red area signifies areas with higher than this level, but most of this area is only slightly above 20 uSv/hr. Areas with 20 uSv/hr or more exist in a relatively narrow strip running northwest from the area of the nuclear plant.
A person lives in an area where the external radiation dose rate is 20 uSv/hr. Of course, this is really only outdoors and inside there will be less contamination, but for the sake of argument, lets assume the worst: They get 20 uSv/hr and they stay in that are all the time. There are 8760 hours in a year, so if they spend all their time outdoors in the 20 uSv/hr area, they receive 175,200 uSv per year or about 175 mSv per year.
This is still a bit unreasonable for what a person would actually be exposed to because it assumes they are always outdoors and standing over ground that has not been in any way cleaned of contamination. Indoors, the level will be a lot lower. If they travel outside the area of highest radiation, their dose is also reduced. As time goes on, both radioactive decay and natural weathering and erosion will reduce levels further. Therefore, after a year in such an area, it’s more reasonable to expect a total exposure of something like 100-150 mSv and maybe quite a bit less.
Most of the no-entry zone is far bellow this. The yellow areas would produce only about half the dose of the highest regions and the areas shaded green would result in an annual dose of only about 10-30 mSv her year. That’s hardly a lot of radiation.
How much radiation a person is exposed to in a year from background sources varies greatly depending on things like location, diet, travel and things like whether they happen to cook with natural gas, live in a granite structure or have radon seeping into their home’s foundation. About 3 mSv is a normal average for those living at sea level in much of the world. Of course, it’s quite common for it to be much higher than this. Areas with background radiation in excess of 10 mSv per year are quite common. A few areas have much higher. In the Guarpari region of Brazil, background levels can exceed 175 mSv per year due to local deposits of uranium and thorium. Residents of Kerala India experience doses of over 70 mSv per year. Ramsir Iran is famous for having some of the highest levels in the world at over 260 mSv per year. Locations across Africa and Australia may produce levels above 40 mSv per year.
Studies have been done of the populations of these areas and no ill effects have been documented as a result of the high radiation exposure. Of course, the expected radiation exposure from living in such an area for an extended period of time would be much higher than for those in the Fukushima area. Since the radioactivity in the Fukushima region is mostly limited to the surface and includes many relatively short-lived radioisotopes, it will diminish significantly in the years to come. Natural sources, on the other hand, are constantly replenished. So a person who lives in an area with increased radiation levels as a result of the Fukushima incident will not experience the same dose next year as they will this year. It will be less.
And no, there have been no calls that high background areas of the world be evacuated and declared off limits.
Visitation:
Living in the vast majority of the area around Fukushima would result in a radiation dose lower than living in many areas of the world and which could reasonably be considered acceptable. Visiting these areas, even for extended periods of time, in order to recover property, secure damaged structures and begin the cleanup would result in even lower levels of exposure. If a person were allowed to travel to the area and spent a cumulative few days in one of the highest areas of radiation, they would receive less exposure than from a dental x-ray. A person could spend a month in the regions of highest radiation and experience a total increase in annual dose that would be less than that millions of people around the world live with for their entire lives. Traveling through the area would result in even lower radiation exposure.
A More Reasonable Proposal:
I’d like to propose a more science-based and less restrictive zoning for the area around the Fukushima nuclear power plant. Under this proposal, the evacuation and no-entry order would be immediately lifted and the vast majority of the area would be available for immediate resettlement, property recovery and rebuilding.
Two zones would remain for the immediate future, the exclusion zone and the limited access zone.
The Exclusion Zone:
The area immediately around the plant boundary. This area would be accessible to plant workers, recovery teams and others involved in the cleanup, survey and general maintenance. The reason for keeping members of the public out is not only to reduce radiation exposure but also because this area is the primary area of remediation activity and is being used as a staging area for equipment and personnel. Those working in the area would need to follow standard procedure for dosimeter.
Limited, escorted visits by those who may live just outside the plant perimeter would be allowed for the purposes of recovering property, surveying damage and securing structures that may remain intact.
Limited Access Zone:
This area is defined not by simple distance from the plant but rather follows the approximate area of the highest radiation levels. Visitation to this area and travel through it would not be subject to major restrictions. The only restriction to access would be that the area would not be zoned for full time resettlement. While those living in that area would be allowed to visit their homes without supervision, they would continue to be offered shelter elsewhere and it would be requested that they not permanently settle into the area or remain there for several consecutive days, although such restrictions would be more of a request than a strongly enforced rule.
Recovery efforts, repair of infrastructure traversing the area and recovery efforts would begin immediately with little or no restriction. As the area would be considered to be free to visit but not designated for resettlement, schools, post offices and other facilities catering to residents would remain closed, but would be repaired and secured. Basic services like fire and ambulances would be restored as soon as possible.
Those wishing to resettle sooner in the area could begin remediation work, such as power washing surfaces and removing top soil and could have their property surveyed for safety and radiation levels. If a government-approved surveyor confirms that the total radiation levels for a structure and surrounding area are within certain standards and that the structure has been repaired to meet building codes, that property could be issued a certificate for residency.
The limited access zone would be the only area subject to government sponsored cleanup and radiation remediation measures. Areas outside this region would only receive such attention if an exceptionally high reading was found on a “hot spot.” Other than that, it’s just not worth the amount it would cost to reduce already low levels.
Eventually all resettlement limits would be lifted and the exclusion zone around the plant would also be eventually withdrawn, pending how the future of the recovery plays out.
This entry was posted on Sunday, March 18th, 2012 at 12:15 pm and is filed under Bad Science, Enviornment, Good Science, Nuclear, Politics. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
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April 3rd, 2012 at 6:46 am
SEE: http://www.naturalnews.com/031910_Fukushima_plutonium.html
They are not clear on the distribution of plutonium out side of the plant, so are playing it safe.
(NaturalNews) All the indicators of a full-fledged nuclear fallout of epic proportions seem to be falling into place as officials at the Fukushima Daiichi nuclear power plant have now announced that deadly plutonium has been detected both inside and outside the plant’s facilities. Levels of radiation 1,150 times the maximum allowable levels have also been detected in ocean water nearly a mile north of the plant’s drainage outlets, confirming previous suspicions that the situation at the plant is far from being under control.
Learn more: http://www.naturalnews.com/031910_Fukushima_plutonium.html#ixzz1qyVlo1Zg
Quote Comment
April 3rd, 2012 at 7:01 am
Richard Perry said:
You are quoting a source from over 1 year ago that was published just weeks after the accident? Get real.
Let us look at what the latest (less than 3 weeks old) news is, shall we.
“The levels of radioactive plutonium around the Fukushima Daiichi nuclear power plant aren’t much higher than the amount of plutonium remaining in the environment from Cold War-era nuclear weapons tests, and it probably poses little threat to humans, a new study indicates.”
http://articles.latimes.com/2012/mar/08/science/la-sci-fukushima-plutonium-20120309
Anyone with any real knowledge who reads your “source”, will laugh.
“plutonium can be difficult to properly detect until it is too late” Nope, it is easy to detect with any alpha detector.
“Plutonium 239 is generally recognized as the most deadly element in the world” Nope, first Pu-239 is a nuclide not an element but even so it is not the most deadly nuclide.
“officials have arbitrarily raised that limit to 250 millisieverts in order to keep relief efforts going” Nope, the 250 millisievert level is a usual limit used in emergencies.
Your source is nothing but year old fear mongering. If you have any real science to bring to the discussion there are many here who will be happy to discuss those issues with you. But outdate and patently wrong information will result in you being treated like a troll, and an ignorant troll at that.
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April 3rd, 2012 at 7:51 am
DV82XL:
“In your first post in this thread you made several unfounded statements, loose assertions, and outright errors. It is not our role to correct you, which anyway has proven to be hopeless in the past. The link that you did give is simply not relevant to the topic at hand, and looks like something you picked at random from a Google search – this is not how one makes a reference.”
- Check the address on that reference. So you are calling the CDC wrong on this.
- You rarely actually try to prove anyone wrong. You engage in attempts at character assassination.
- It is your duty to prove me wrong if you insist that I am wrong. I thought proof was what this was all about. I thought that was science. Instead, I provide proof and you ignore it and sidetrack the dialog with unfounded defamatory remarks.
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April 3rd, 2012 at 9:39 am
Richard Perry said:
Wow, someone stupid enough to quote natural news here and actually expect us to believe it.
I think ddpalmer dealt with that well enough.
fixx said:
Maybe you should read what he actually typed, not what you’d like to argue against.
fixx said:
When the burden of proof is on you and you can’t meet it there is no obligation on anyone else to prove you wrong, you have to prove yourself right first.
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April 4th, 2012 at 8:05 am
“Maybe you should read what he actually typed, not what you’d like to argue against.”
- I suspect you are associating my response with the wrong part of his response.
- My point with this guy is that he rarely provides the references and proof (or even a logical extension of facts) that he expects from anyone who disagrees with him. He slings mud, an odd characteristic to admire.
“When the burden of proof is on you and you can’t meet it there is no obligation on anyone else to prove you wrong, you have to prove yourself right first.”
- The burden of proof truly belongs to those who are potentially putting people in harms way. The goal is to err on the side of safety. This has been the policy in every place I’ve ever worked and it is a mindset I happen to agree with. If you believe in the acceptable loses model then I can’t argue your belief in it.
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April 4th, 2012 at 8:31 am
fixx said:
The problem for those who don’t believe in the acceptable loses model is that not accepting it to some degree is impossible.
Simply put, you can’t have complete safety, thus you need to optimise risk.
Quote Comment
April 4th, 2012 at 12:43 pm
fixx said:
In logic, and rhetoric it is technically impossible to prove something wrong, the best one can do is prove the opposite right. Nevertheless when debating any issue, there is an implicit burden of proof on the person asserting a claim; if this responsibility or burden of proof is shifted to a critic, the fallacy of appealing to ignorance is committed. This is as standard as it gets. If you need to see a reference for this, Google “Burden of Proof.”
Yes, I am openly critical of posters like you who have not bothered to learn a subject and then make unsubstantiated statements about it. It is particularly galling when this ignorance is entrenched and delivered with arrogant self-assertion. Inevitably threads get derailed (as this one has) trying to deal with these people, and I am tired of it. And this is why there are rules like Burden of Proof – endlessly needing to deal with random statements by those that haven’t bothered to apprise themselves of the facts on their own is simply non-productive and no progress can be made.
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April 8th, 2012 at 8:40 pm
[...] very frequent basis. The view is set to "news". Try clicking on "video" and "2" for more articles. >[caption id="" align="alignright" width="166" caption="Logo of the National Science Foundation (NSF)...imedia.org/wikipedia/commons/3/3e/Nsf1.jpg" alt="Logo of the National Science Foundation (NSF)...." [...]
Quote Comment
April 16th, 2012 at 1:19 am
@#58 About “US Students Need New Way of Learning Science”:
There may be merits to the “8+1″ conceptual model for a basic science curriculum, though it’s obvious from reading the original article that it’s an “under development” type of concept. However, it has no real place in this discussion as it is an attempt at derailing still further a discussion on the governmental radiation evacuation policy in Japan. I assume you are trying to insinuate that the educated posters here have an inadequate level of education, but you will find (if you understand the real meaning of the “+1″ part of education) that you are far from correct.
I have lurked here in Depleted Cranium for a quite some time and learned to respect the opinions of several of the regular posters because they are in consistent agreement with my personal knowledge and the information that I can reference when I don’t have the personal knowledge, and they can explain concepts well enough to demonstrate reasonable mastery of their personal areas of expertise.
Try reading, debating, asking questions and learning. This is a good place for it.
Quote Comment
May 2nd, 2012 at 2:53 am
Hi all! I’ve been away from this site for a long time, so it is good to be back and commenting on my favorite topic – radiation protection.
First I would like to say that Buzzo’s suggestion to temporarily allow folks into areas of low exposure is a great idea. Fixx needs to review the basic radiation protection principles of Time, Distance, Shielding and Contamination Control. Allowing people to enter low dose areas for a limited time is unlikely to give anyone any kind of harmful dose.
It is easy to calculate and employ the Time principle of protection when the areas have been reasonably surveyed for dose levels. US regulation allows for 1 mSv (100 mR) exposure to the general public above background levels. At a .02mSv/hr (2 mR/hr) reading, a person can spend 50 hours searching for their belongings. So why the heck not let them do it?
As Robert pointed out, there are only two nuclides that they are now detecting above natural levels: 137-Cs and 134-Cs. Both are beta-gamma emitters, therefore easy to detect with a standard G-M meter. Cs-137 will predominate. Cesium does not remain in the air for very long, and as it settles out of the atmosphere it can take many pathways. Is there potential for ingestion? Sure. However, unless a dwelling was breached (e.g. roof blown away) prior to the passing of the airborne Cs, it is unlikely that contamination would have gotten into the structure unless air handling systems were left on. People who live near a nuclear power plant are instructed to shut down air handling systems in the event of an accident. If they did and there is no breach of the structure, then the risk of contamination inside the structure goes pretty much to zero.
The Japanese are generally a smart group of people. Give me an hour or two of simple radiation protection instruction, and I would expect very minimal doses to those who enter the low dose areas.
Quote Comment
May 2nd, 2012 at 3:10 am
The more I think about Buzzo’s idea, the more I like it. With a little instruction, the people could be taught to use a meter and how to collect environmental samples. Think of the data they could bring back that would help guide policy making and understanding of the effects of the accident.
Quote Comment
July 8th, 2012 at 5:27 am
lots of information on these matters are given on the site of
Professor Wade Allison . He is a nuclear and medical physicist at the University of Oxford .
The standard on radiation are so expensive and illogical according to him , that he proposes to have them replaced by more adequate one’s .. Like 100 mS /one time dose or max monthly .. That would imply that nobody would have to be evacuated from the Fukoshima “hot” zone or “exlusion” zone. It would make this disaster a lot cheaper than proposed now.
He is the adversary of Chris Busby that leads a pseudo scientific propaganda information body, created by the green party.
http://en.wikipedia.org/wiki/European_Committee_on_Radiation_Risk
The European Committee on Radiation Risk (ECRR) is an informal[1] committee formed in 1997 following a meeting by the European Green Party at the European Parliament to review the Council of Europe’s directive 96/29Euratom, issued in May of the previous year.[2]
It lookes guinine in the first instance but it is a phony organization, to impress not knowing information gatherers with info that looks scientific but is not.
Here a links describing Prof Wade’s idea’s
http://www.theaustralian.com.au/news/world/british-physicist-wade-allison-calls-for-radical-increase-in-radiation-exposure-limits/story-e6frg6so-1226159573330
“The chance that any worker dies as a result of radiation exposure at Fukushima is less than 25 per cent,” he said.
So far, eight workers at Fukushima have been exposed to more than the government limit of 250mSv of radiation, which was increased from 100mSv during the crisis.
Professor Allison said the evidence from Chernobyl and the Hiroshima and Nagasaki nuclear bombs showed there was no cancer risk under 100mSv and minimal risk even up to quite large exposures.
He has proposed new limits as high as 100mSv for a single dose or as a monthly maximum, and 5000mSv as a lifetime exposure.
Professor Allison said he supported nuclear energy as part of the solution to climate change but was not part of the industry and had never accepted work or money from it.
http://www.radiationandreason.com/
http://www.imaging.ox.ac.uk/network-members/wallison/
Quote Comment
August 1st, 2012 at 12:20 am
DV82XL said:
- Still waiting for you to attack the argument instead of the arguer. If it is so easy to prove people wrong why don’t you do it? So far you are just repeating yourself. You don’t seem to get tired of that.
Leg said:
” Fixx needs to review the basic radiation protection principles of Time, Distance, Shielding and Contamination Control. Allowing people to enter low dose areas for a limited time is unlikely to give anyone any kind of harmful dose.”
- I’m curious what exactly I said that makes you think I am unfamiliar with these concepts.
- I am also familiar with the concept that a value can approach 0 without ever reaching it.
- Your last sentence of that paragraph is not actually as reassuring sounding as you may have thought it was.
To think that increased radiation to whatever small degree will have no effect is ignorant. To think that some of the effects will not be harmful is optimistic. To tell people to wear a dust mask is irresponsible. I am and have always been aware that we are being bombarded with radiation by natural sources. Our bodies are constantly repairing damage from these (and other) assaults. We have evolved in radiation so we have mechanisms. Different people will have better mechanisms then others just as some people will have had more life long exposure to radiation from various sources. The cusp will not be the same for everyone and some people will die from the radiation expelled by this disaster, that is realism. To expose people who have already had an unknown amount of exposure to more does not seem responsible to me.
Quote Comment
October 26th, 2012 at 9:51 pm
The thing I like most about the proposal (though I may quibble about some of the details) is the fact that it puts the onus for getting decontamination done squarely where it will work the best, the property owner.
If anyone will push to get their property surveyed and cleaned up, it is the owner. I know I’d be there as soon as I could.
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