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Japan has over 100 active volcanos and is in the most seismically and volcanically active zone in the world. Nuclear Energy is dangerous everywhere, but more dangerous than average in Japan, as demonstrated by Fukushima, which is the still leaking into air and water by TEPCO’s own admission. No stop to its leaking and belching of radionuclides into air and water appears in sight.

The problem of mixing earthquakes, volcanos, and nuclear energy has not been resolved by Japan. It is an obviously unresolvable. Nonetheless, the world being what it is today, experts had to do studies to explain that Japan hasn’t resolved the unresolvable.

Japan is in the Ring of Fire, the most seismically and volcanically active zone in the world. http://pubs.usgs.gov/gip/dynamic/tectonics.html
See also: https://miningawareness.wordpress.com/2015/02/23/why-the-recent-japan-earthquakes-japan-trench-no-place-for-nuclear-reactors-beam-me-up-scotty/
Japan plates, USGS, Rhea et. al., 2010 Japan plates, USGS, Rhea et. al., 2010
108 of Japan’s volcanos. There are at least 110 active ones.
108 Japanese Volcanos via wiki http://en.wikipedia.org/wiki/List_of_volcanoes_in_Japan

It takes time to shutdown reactors or remove fuel. There is inadequate warning time for both earthquakes and volcanos – often none. (See: https://miningawareness.wordpress.com/2014/10/19/japan-more-larger-volcanic-eruptions-expected-over-next-decades-a-ticking-nuclear-time-bomb/)

Even the pro-nuclear IAEA in “Volcanic Hazards in Site Evaluation for Nuclear Installations for protecting people and the environment, No. SSG-21 Specific Safety” warns that “volcanic events can present significant hazards for nuclear installations.” (p. 7) and on pp. 8-9, Table 1, give volcanic phenomena-characteristics which would affect nuclear installations and most of which preclude the siting of a nuclear reactor. http://www-pub.iaea.org/MTCD/publications/PDF/Pub1552_web.pdf
Sakurajima by Krypton, CC-BY-SA-3.0
Sakurajima by Krypton, CC-BY-SA-3.0, via Wikipedia.

In a Tuesday, 11 August, 2015, Press Release Greenpeace Stated:
The Sendai unit 1 reactor has not operated since May 2011. The NRA has failed to apply robust safety measures to the Sendai reactor; including that:

the NRA approved an assessment by Kyushu Electric Power, which excluded major seismic risks at the Sendai plant and violated the NRA’s own post-Fukushima safety guidelines;

an analysis commissioned by Greenpeace Japan in February showed that the NRA also accepted a flawed volcano risk analysis from Kyushu Electric Power for the active volcano Mt. Sakurajima, located only 50km from the reactor site;

the NRA failed to require Kyushu Electric to complete its ageing related operational safety plan before passing the reactor review;

public opposition in Kagoshima prefecture includes deep concern over the failure to have effective emergency planning measures, including plans for the evacuation of elderly and those in hospital.” (Read the entire press release here: http://www.greenpeace.org/international/en/press/releases/Greenpeace-warns-Sendai-nuclear-restart-will-not-end-nuclear-crisis-facing-Abe-government/

The sign of "tsunami attention!" In elementary school temporary shelter http://greenpeace.org/japan/ja/high/news/blog/staff/1024/blog/51089/
The sign of “tsunami attention!” in elementary school temporary shelter. http://greenpeace.org/japan/ja/high/news/blog/staff/1024/blog/51089/

From:
Technical Issues of Japanese Seismic Evaluations from the Point of Global and Japanese Standards

Greenpeace Summary

Greenpeace Japan commissioned independent consultant Satoshi Sato, former nuclear engineer at General Electric from 1984-2002, to assess the seismic standards as applied to the Kyushu Electric Sendai nuclear power plant and accepted by the Nuclear Regulation Authority (NRA). Some main points of the report are listed below.

The International Atomic Energy Agency (IAEA) recommends determining a safe design-basis-earthquake based on seismic events occurring with a probability of once every 10.000 to 100.000 years (annual exceedance probability 1E-4 and 1E-5).

However, the design-basis-earthquake, presented by Kyushu Electric, indicates the probability of a higher frequency, with seismic events happening partially once every 1.000 – 10.000 years (annual exceedance probability 1E-3 and 1E-4), which violates the IAEA’s safety standards.

In the Construction Permit Application Kyushu Electric submitted to the NRA, only the continental crust was considered as a seismic source for the Sendai Nuclear Plants’ non-seismic isolation buildings and not seismic sources at plate interface and within oceanic plate. As a result, the earthquake impacts from lower frequency (longer period) region of vibration spectrum, which has caused serious consequences in past nuclear accidents, are underestimated.

The lower frequency (longer period) region of vibration spectrum should not be underestimated, as it can lead to the destruction of tanks, pools and transformers in the reactor caused by swelling liquids (sloshing effects) as well as to great damage to machines, such as overhead polar cranes, lower pressure turbine rotors and underground pipes.

There have been examples both in the US and Japan of how seismic induced vibration from earthquakes has caused a sudden and excessive nuclear reaction (reactivity addition) of the fuels in the reactor, leading to an emergency shutdown of the reactors. This could also be effected by lower frequency (longer period) region of vibration spectrum; and it is a major problem that this point is not verified.

Based on the findings above, although each of the three newly developed design-basis-earthquakes (Ss-1, Ss-2, and Ss-L) developed by Kyushu Electric and approved by the NRA are significantly higher than previously, the methodology used by Kyushu Electric and accepted by the NRA is greatly different from the probabilistic seismic hazard analysis (PSHA) applied in the United States for the nuclear plant at Vogtle. It is difficult to determine if the methodology uniquely developed for Japanese nuclear plants is consistent with international practice. Nonetheless, the conclusion of the commissioned report is that the newly developed process to determine the design-basis-earthquake for the Sendai Nuclear Power Plant is less than adequate, simply because of the intentional separation of lower frequency (longer period) side of spectrum contributed from the long-distance earthquakes.

When comparing the process of determining the design-basis-earthquake in Japan to other examples in the U.S. and other countries, there are many unclear elements in the Japanese process, as it is not worked out comprehensively. It is unacceptable to promote this process as the highest standard in the world.

The author clearly states that the arguments delivered in this report do not only apply for the Sendai plant but also for all other remaining nuclear power plants in Japan.http://www.greenpeace.org/japan/Global/japan/pdf/20150428-seismic-evaluation-en.pdf (Read at link. See more comprehensive summary further down on this blog post, after volcano discussion).

Even the pro-nuclear IAEA in “Volcanic Hazards in Site Evaluation for Nuclear Installations for protecting people and the environment, No. SSG-21 Specific Safety” warns that “volcanic events can present significant hazards for nuclear installations.” (p. 7) and on pp. 8-9, Table 1, give volcanic phenomena-characteristics which would affect nuclear installations and most of which preclude the siting of a nuclear reactor. http://www-pub.iaea.org/MTCD/publications/PDF/Pub1552_web.pdf

Excerpted from the John Large submission regarding volcanos in the Sendai Injunction case:
From “Statement of John H. Large” 12-17:
“61 My understanding is that the volcanic activity on and around Kyushu is likely to comprise a series of volcanic fields and linked magma reservoirs, from which the formation of new vents could open up closer to the Sendai NPP site. If the screening distances fail to take into account the potential for new vents to form at some considerable distance from existing and past-established caldera, then the NPP site could be brought within the distal range of several types of volcanic activity.

On the following page 13-17, he notes that the NPP licensee is allowed “to rely solely upon the geologic record of a single, past tephra fall” and
64 In fact, reliance upon the geologic record of a single past event is most unreliable. Far better, and again as encouraged by IAEA SSG-21, is the deployment of a probabilistic approach using a numerical simulation of tephra fallout at the NPP site… a Monte Carol simulation of the ash fall deriving from each capable volcano should be conducted, including for variations of eruption or ejecta volume, eruption column height, ash grain particle size and size distribution, win and atmospheric stability – none of these requirements are set out in VAG.” [each is emphasized in the original] (From : “The Application and Conformity of the Japanese Nuclear Regulation Authority’s New Safety Standards for Nuclear Power Plants: The Assessment Guide of Volcanic Effects to the Nuclear Power Plant with International Atomic Energy Agency’s Volcanic Hazards in Site Evaluation for Nuclear Installations SSG-21, 2012, Opinion and Statement of John H. Large“, Current Issue Date: 28 January 2015) Read the entire statement here: http://www.greenpeace.org/japan/Global/japan/pdf/large_submission_Sendai_injunction_case.pdf

Technical Issues of Japanese Seismic Evaluations from the Point of Global and Japanese Standards

Summary

This technical report reviews the methodology used by the Nuclear Regulation Authority I(NRA) in assessing the seismic risks for nuclear power plants in Japan. It also assesses the approach used by Kyushu Electric Power Company in its seismic assessment for its two Pressurized Water Reactors (PWRs) at the Sendai power plant.

Some significant findings are briefly described in the list below. Detail of each finding and its technical basis are discussed in the main part of this report.

(1) The methodology and the process to determine the Hard Rock Response Spectra and the Free-Field Ground Surface Response Spectra are only roughly and conceptually explained and are largely left in a “black box”, making it impossible to objectively verify the adequacy. There is no evidence found in the Safety Evaluation Report supporting that the NRA has done it in a thorough manner.

(2) After all, a total of three different ground surface response spectra are proposed as the design-basis-earthquakes, consisting of Ss-1 and Ss-2 as mentioned above, and Ss-L separately and exclusively proposed for the Seismic Isolation Building. However, the author believes that there should ideally be just a single design-basis-earthquake bounding all three response spectra instead of three different spectra. The author also believes that the justification claimed by the Kyushu and accepted by the NRA to exclude the potential contribution from seismic sources at the plate-to-plate interface by simply implying that the earthquake of the seismic intensity V or greater generated at such a long distance is not anticipated based on the historical data is technically invalid. The author is concerned about the conclusion not to require to superpose the lower frequency (longer period) side of Ss-L spectrum contributed from the long-distance seismic source over either Ss-1 or Ss-2 because it is in fact the lower frequency (longer period) region of vibration spectrum that is mostly responsible for the earthquake impacts previously experienced in the Japanese nuclear power plants. The lower frequency (longer period) region of vibration spectrum of Ss-L should be integrated into design-basis-earthquake applied for the structures, systems, and components not only of those inside Seismic Isolation Building but also of those inside other plant facilities.

(3) Technical credibility of Uniform Hazard Spectra constructed by the Japan Nuclear Energy Safety Organization (JNES) in 2005 and in accordance with the methodology developed by the Atomic Energy Society of Japan (AESJ) in 2007 is questionable and possibly non-conservative. Nevertheless, there is no objective evidence in the safety evaluation report to support that the NRA has thoroughly assessed the adequacy of these hazard spectra which apparently are other examples of black-box in terms of development processes.

(4) The land territory of Japan is divided into eight regions in a very rough manner by the JNES (2005). Such a regional map suggests that all four sites of Fukushima Daiichi, Fukushima Daini, Tokai, and Kashiwazaki-Kariwa belong to the same region, and all sites of Hamaoka, Shika, and the sites along Wakasa-Bay belong to the other same region. It does not seem to be reasonable to apply a single set of uniform hazard spectra to each of such vast regions. Nevertheless, there is no objective evidence in the safety evaluation report to support that the NRA has thoroughly assessed the adequacy of this map.

(5) By comparison with those hazard spectra mentioned above, the Kyushu Electric Power Company has derived an overall conclusion that the annual exceedance probability of their design-basis-earthquake is somewhere between 1E-4 and 1E-6 or between 1E-4 and 1E-5. However, those figures referenced in the text actually do not fully support such a conclusion statement. For example, the Ss-2 (vertical) spectrum indicates the annual exceedance probability being between 1E-3 and 1E-4 with some portion even greater than 1E-3. The NRA obviously failed to point out this error. Based on the findings above, although each of the three newly developed design-basis-earthquakes (Ss-1, Ss-2, and Ss-L) developed by Kyushu and approved by the NRA is significantly higher than previous PGA of 180Gals, the methodology used is greatly different from the probabilistic seismic hazard analysis (PSHA) applied for the Vogtle plant and it is difficult to determine if the one uniquely developed for the Japanese plants is consistent with the international practice. Nonetheless, it is author’s personal opinion that the newly developed process to determine the design-basis-earthquake for Sendai Nuclear Power Plant is less than adequate simply because of the intentional separation of lower frequency (longer period) side of spectrum contributed from the long-distance earthquakes.

(6) In the seismic response analysis of the containment, the soil-structure interaction (SSI) is considered to be one of the key factors. Although the analysis model contained in the Construction Permit Application implies the consideration of this factor, no values are given to the spring constants of horizontal springs and rotational spring. Therefore, it is not clear if the effect of SSI is really included in the analysis. And if it is not properly considered, the expected output of the analysis could become non-conservative (under-estimation of the seismic behavior) especially in the lower frequency (longer period) side of response spectrum.

(7) By under-estimating the lower frequency (longer period) side of seismic behavior, the estimated impacts to the sloshing effects to the tanks, pools, and large transformers, and those steel structures of long span such as the fuel handling machine, overhead polar crane, and meteorological tower, as well as those components not tolerable for the large displacement such as the stainless steel liner of pools, lower pressure turbine rotors, underground pipes/trenches, become all non-conservative.

(8) By under-estimating the lower frequency (longer period) and larger displacement seismic motion, there are potential hidden risks that could result in various unfavorable consequences to the performances of severe accident mitigation guidelines, the physical protection systems, and the fire brigade activities. For instance, the damages to the roads assigned for the transportation of mobile equipment to mitigate the severe accident, the derailed physical protection gages, and broken emergency lights inside building could significantly hinder the critical actions under the emergency. If the ceiling of the building is heavily loaded with moistened volcanic ash or wet snow, and the natural frequency is lowered sufficiently, it may resonate with the lower frequency of earthquake, resulting in a collapse to the important equipment underneath.

(9) It has been learned from the previous events that the seismic vibration creates some perturbation to the coolant in proximity of fuel rods and adds extra positive reactivity. Fortunately, such previous events have not resulted in fuel failure. However, the possibility of exceeding the safety limit, leading to the gross fuel failure and damage to the reactor pressure boundary under unfavorable conditions and/or severer seismic events should be assessed.

It should be noted that the findings listed above are not unique to the Sendai Nuclear Power Plant alone and are generally applicable to all nuclear power plants in Japan including those of BWR designs.” ( From Greenpeace Commissioned Report, April 28th, 2015, Technical Issue of Japanese Seismic Evaluation from the Point of Global and Japanese Standards. Written by: Satoshi Sato (Nuclear Consultant) © Greenpeace Entire Evaluation is found here: http://www.greenpeace.org/japan/Global/japan/pdf/20150428-seismic-evaluation-en.pdf

See also: https://miningawareness.wordpress.com/2014/11/07/japanese-governor-ito-approves-nuclear-restart-at-sendai-ignores-volcano-risk-lack-of-evacuation-plans-fukushima-lessons/