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The records I am seeking in FOIA/PA Case 2012-170 and 2012-190 are, expected to be classified and could be withheld because their sensitiveness because of content of are so catastrophic. However, Their content can, in reality, be expected with high plausibility just by using materials in public domain. That will be illustrated in this paper. 

  　Since those scenarios are foreseeable just gathering disclosed information, that malicious entities ( like terrorists ) can easily lead to the same conclusion if they endeavor for that purpose. So releasing the materials do not increase the risk of malicious attack to nuclear facilities. 

 On the other hand, by disclosing and clearly informing ordinary persons what the possible worst cases were, and how we responded to that, our society can lead to well balanced policy decision making through deliberation by public. Therefore, public interests achieved by disclosing those records override the possible downside of doing so.

Content.

A. On 5 Worst Cases

1 Source Term

2 Wind Direction

3 Consequences of Huge Release to the Atmosphere

4 Contributing the Deliberation of the Public

B. Supplementation for Dose Rate Calculation

 A. On 5 Worst Cases

1 Source Term

When you simulate quantity of the radioactivity release to the atmosphere, you need to know how much radioactive materials are concerned. around 15000 fuel rods in Fukushima Daiichi Site. The consequence of their release proportionately increase the quantity of fuel rods.

As for the nuclide estimated to deposit in environment, document Japanese Atomic Energy Commission Chairman Shunsuke Kondo drafted in 25, March 2011 projects the Cs 137 contamination in 170km and 250km from the site in page 12. According to the words”１炉心分 and ２炉心分” (1 core equivalent and 2 core equivalent ) and the calculation Japanese Government submitted to the Tokyo district court, 548 and 1096 fuel equivalent are assumed. Therefore, the total release of Cs137 is about 14 times larger than shunsuke Kondo document, if 100 % of 15000 fuels were released.

Although other nuclide quantities, except for Strontium 90, are not given yet in Kondo document, we can discover reports on radioactivity release rate of Cs137 and other nuclei and in Bq . One examples OECD report ” Chernobyl Ten Years On ” and UNSCEAR’s assessment of the radiation effect on Chernobyl Accident is also a reliable source for reference.

Here, it must admitted that the real nuclei composition in Fukushima Daiichi site is complex because other parameters are not given; i.e. Fukushima Daiichi uses MOX fuel. Additionally, some fuels were used, others not. However, Since the documents now concerned are simulation just after Fukushima crisis happened, one may assumed the calculation shall be simple and dismiss the difference of radioactivity composition contribute to the document’s conclusion.

Another hint to foresee the records I am asking can be seen in documents already disclosed to FOIA. In page 7 to 8 it illustrates 25% of Unit 2 and 50% from Unit 3 SPF and 100% release from SPF in Unit 4. The consequential radioactivity is around 2000 fuel rod equivalent. Still, one can not confirm the atmosphere release above consists ” 5 worst cases ”, you can see ” At least 2000 fuel rods equivalent or so are given as a source term ”

In conclusion, as the source term records contain at least 2000 fuel equivalent, at most 15000 equivalent from Fukushima Daiichi. And all the documents in public domain I referred combined, total release of radioactivity in each nuclei can be seen.

2 Wind Direction

Wind direction, also contribute the way radioactivity goes and its composition. However, here I have to carefully refrain from conclude whether all the 5 worst cases considered wind direction. Some of them may have dismiss the wind direction because of the complexity to calculate. Even though, a name appears in already disclosed document, ”Tokyo Super Core Scenario” suggests it assumed the wind direction oriented to Tokyo. Also, the document mentioned above cares meteorological condition, to show the need of protective measures in U.S. Further more many documents already available takes into wind direction. Though I have to refrain from conclude how precisely records cared about wind ( they may, or may not have considered vertical wind direction ) it is highly probale wind directions are considered, at least some of your ”5 worst cases”

3 Consequences of Huge Release to the Atmosphere

It is not certain whether and how the effect of radioactivity release were cared in ” 5 worst cases ” however, to see the consequences of huge release from Fukushima which may be written, you can refer Henry Kissinger’s 1957 Edition of ”Nuclear Weapons & Foreign Policy ”. In the Chapter ”The fire of Prometheus” (which is abridged later editions perhaps because its pervasive nature ) , he illustrates the possible damage caused by thermonuclear weapons. Although nuclear power plant accident is different from thermonuclear weapons, they have in common on large scale of fall down. There should be difficulty of evacuation, lack of medical resources, food contamination, etc. Health Risks, including acute study, log term effect, and genetic mutation by Sr90 are mentioned. For more update, National Academie’s BEIR can be available.

And the number of possible casualty is shown to the public. The Asahi Shimbun report the Japanese MOFA research on military attack to nuclear power plant. It estimates 18000 could be dead by acute syndrome at worst case, given an average location and population of nuclear power plants in Japan, in case if evacuation had not been done at all. As shown in the article, this assessment dates back to 1984, almost 30 years ago, so the calculation in the same way must be easier for mal concerned entity. Though the article does not directly mentions the quantity of materials concerned in assumption, it describes ” the areas 87km radius from the site ” may need to be relocate. Exploiting the land contamination above written, you can calculate back to the radioactivity this assessment matters, then the fuel rod equivalent, and other nuclei quantites.

One thing you do not have yet is timing, duration of release to the atmosphere, however, P9 in Shunsuke Kondo scenario or ”96 hours” can be put into the paremeter.

All of those combined, you can get to, a rough illustration of ”5 worst cases ” in Fukushima crisis simulated by U.S. Government. With some scientific knowledge, one can exploit those information to project the possible damage of radioactivity release the attack to nuclear facility would cause.

It does not mean disclosing the information of ”5 worst cases ” benefit mal intended country or terrorist and harm our public interest. Malicious entity with equipment to attack nuclear facility can easily lead to the projection ”5 worst cases” shows. Disclosing the records, do not harm our public interest.

4 Contributing the deliberation of Public

On the contrary, normal publics are not so much informed about the possible consequence of nuclear facilities. Some overestimates it, others underestimates it. Those misunderstanding, thwart sound deliberation based on correct information. The records I am seeking here shall, if clearly seen and paid attention, strongly contribute to the public understanding of the way to calculate, prepare, and manage the risk of nuclear accident. Also, how you managed given the simulation records show shall tell much about the way dealing the catastrophic in the future and manage to do it.

It does help, I believe, better policy making in the process of democracy.

B. Supplementation for Dose Rate Calculation

The dose rate can be projected by given the source term and the meteorological condition. The source term is given as illustrated above. Though it is not easy to make an accurate calculation of the record estimated, many meteorological projections are shown since the accident. And also, the mention seen in the released documents hint the conservative calculation of thyroid and effective dose rate in U.S. in certain source term.

It does not make publics confuse or benefit mal intended groups. Rather it can be a source for better informing us.