Japan Nuclear Plant: World's Biggest May Be on Fault

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Discussion Overview

The discussion revolves around the seismic safety of the Kashiwazaki-Kariwa nuclear power plant in Japan, particularly in light of its potential location on an active fault line. Participants explore the implications of recent earthquakes, the adequacy of geological surveys prior to construction, and the broader context of nuclear safety standards in Japan compared to other countries.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants express concern over why a nuclear plant would be built on a fault line and question the thoroughness of geological surveys conducted prior to construction.
  • Others suggest that while geological surveys are required, it is possible for inactive faults to be missed, raising questions about the reliability of such assessments.
  • Participants note that the Kashiwazaki-Kariwa plant was not designed to withstand the recent earthquake's magnitude, which has implications for its safety standards.
  • There are differing views on the adequacy of Japan's earthquake safety standards, with some arguing they are insufficient while others believe Japan takes seismic safety seriously.
  • Some contributions highlight that the plant's response to the earthquake, including the minor radioactive leak, may indicate a level of safety in its design despite the concerns raised.
  • Participants discuss the historical context of the plant's construction, noting that it began operations in 1985 and that options for relocating plants in Japan are limited due to the country's geography.
  • There are mentions of past accidents and cover-ups related to nuclear safety in Japan, which complicate perceptions of the country's commitment to safety standards.

Areas of Agreement / Disagreement

The discussion reflects multiple competing views regarding the adequacy of geological surveys, the seriousness with which Japan approaches earthquake safety, and the implications of the recent earthquake on nuclear safety. No consensus is reached on these points.

Contextual Notes

Participants note that seismic analysis is a critical part of nuclear plant design, but there are concerns about the standards applied to systems not directly related to the core and containment structures. The discussion also highlights the historical context of the plant's construction and the challenges of identifying active faults.

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http://www.bloomberg.com/apps/news?pid=20601101&sid=a8qFB6xPyJyk&refer=japan

Japan Nuclear Plant, World's Biggest, May Be on Fault (Update1)

By Megumi Yamanaka and Jason Clenfield

July 18 (Bloomberg) -- The world's biggest nuclear power station, located in central Japan, may be on a seismic fault that shifted in a magnitude 6.8 earthquake this week, causing a radioactive leak into the ocean.

Reports by Japan's weather bureau suggest ``a fault line runs under the plant grounds,'' owned by Tokyo Electric Power Co., Akira Fukushima, deputy director-general for safety examinations at the nuclear and industrial safety agency, told reporters in Tokyo today.

The Kashiwazaki-Kariwa plant was not designed to withstand an earthquake as powerful as the one that killed nine people in Niigata prefecture July 16, nor does the facility meet the trade ministry's new earthquake standards put in place last year, Fukushima said.
 
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That's scary. Why wouldn't they do a geological survey before building a nuclear plant (or any power plant...no matter your source of energy, you don't want the whole plant going down in case of an earthquake) and put it in a different location rather than on a fault line? What's the likelihood of missing a fault line during a geological survey and only realizing it's there after an earthquake? (That's a real question, not a rhetorical one...I don't know if there are factors that would make it possible to honestly miss the presence of a fault line.)

Or, are there truly no other options in Japan as places for putting a plant?

I haven't seen any updated reports on the leak, but at least according to the first day's reports, it really was minor. I know people panic when they hear radioactive leak, but there is natural radioactivity all around us, and if it's being quickly diluted into the ocean, it may not be much of a concern at all as long as they stopped it from continuing. In a way, it actually speaks more to the safety of the plant that it withstood such an earthquake, sustained the type of damage it did, and did NOT have a catastrophic failure.

It seems a little odd to be expecting it to meet brand new earthquake standards though. Even if there is a requirement to retrofit to meet the new standards, that's not likely to be something that could be accomplished in less than a year unless they were already very close to meeting those standards.
 
The article does a good job of putting the leak into perspective - we'll have to wait and see, though, what the later reports say about the actual magnitude and failure mode.

I think the point of bringing up the new earthquake resistance standards is to imply that the standards should have been tougher previously. That may be true.
 
I can't think of any country that has taken earthquake resistance as seriously as Japan.
 
FredGarvin said:
I can't think of any country that has taken earthquake resistance as seriously as Japan.
And yet, they built a reactor on a fault line. Yikes.
 
jimmysnyder said:
And yet, they built a reactor on a fault line. Yikes.
Pretty much the whole country is a fault linem, as silly as rebuilding San Francisco in the same place.

In the past they tried alternative ways of securing acess to nearby fuel reserves but that also caused quite a bit of trouble.
 
The malfunctions and a delay in reporting them fueled concerns about the safety of Japan’s 55 nuclear reactors, which have suffered a string of accidents and cover-ups. Nuclear power plants around Japan were ordered to conduct inspections.

http://www.msnbc.msn.com/id/19778870/

So it's not that they take earthquake resistance more seriously than the rest of the world, it's just that they cover it up more?
 
Why wouldn't they do a geological survey before building a nuclear plant (or any power plant...no matter your source of energy, you don't want the whole plant going down in case of an earthquake) and put it in a different location rather than on a fault line?
They would and they are required to do so. But they could have missed a particular fault, especially if it had been inactive. On the other hand, I don't know the details of TEPCO's geo-survey's. Seismic analysis is part of plant design and qualification.

Here is the historic seismic activity map from USGS
http://neic.usgs.gov/neis/eq_depot/2007/eq_070716_ewac/neic_ewac_h.html
Note the star, which corresponds to the 6.6 mag earthquake of July 16.

http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2007ewac.php#details
http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2007ewac.php#maps

Today I read that the Kashiwazaki_Kariwa NPP has been shutdown indefinitely, and I imagine that some managers will be dismissed. It is troublesome with the spills of contaminated material and malfunctions.


First KK unit went online in 1985, and they just continued building at the site. They really do not have a lot of options to build elsewhere in Japan.
 
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Inspectors reportedly identified four fault lines in the area while conducting a geological survey before work began on the Kashiwazaki plant in 1980 but concluded that they were inactive, according to the Asahi newspaper.

The Citizen's Nuclear Information Centre said that the fault believed to have triggered the earthquake was not discovered during pre-construction surveys. "Clearly Japan's earthquake safety standards are inadequate," it said in a statement.

http://www.guardian.co.uk/japan/story/0,,2129237,00.html

The scary part here is that no one else takes this stuff more seriously than they do.
 
  • #10
The US and Europeans take nuclear energy pretty seriously.

I get involved in some matters, and believe me - we take it very seriously - and that just adds to the stress.

Nuclear Plant Safety at Issue After Japan Quake
http://www.npr.org/templates/story/story.php?storyId=12091969
Morning Edition, July 19, 2007 · Regulators in Japan discovered a fresh leak of radioactive material from the world's biggest power plant, Tokyo Electric Power, after an earthquake in northwestern Japan this week. It has been closed indefinitely. According to an official at Japan's Nuclear and Industrial Safety Agency, the plant may actually have been built on an active fault line. Adrian Heymer, senior director of new plant deployments at the Nuclear Energy Institute, a policy group for U.S. nuclear companies, spoke with Linda Wertheimer
 
  • #11
Astronuc said:
The US and Europeans take nuclear energy pretty seriously.
But FredGarvin was focused on earthquake resistance. Do the US and Europeans take it more or less seriously than the Japanese? My impression at the moment is that Japan doesn't take it all that seriously, and if Fred is right, we're in deep trouble here.
 
  • #12
jimmysnyder said:
But FredGarvin was focused on earthquake resistance. Do the US and Europeans take it more or less seriously than the Japanese?
Seismic analysis is an important part of ensuring the structural integrity of a nuclear system, and the core and primary system, and the containment and auxilliary structures are built to certain standards in order to ensure that the public is protected against the consequences of an accident.

For new plants, particularly in the US and Europe, not only do they have to meet strict seismic codes, but we now have to ensure that heavy commercial aircraft fully loaded with fuel will not penetrate containment or auxilliary building, and will not compromise the integrity of the core or any spent fuel storage systems.

There are some considerations here with respect to the KK NPP:

1. They very well could have missed an inactive fault. Presumably an investigation will shed some light on that.

2. There are many systems supply the nuclear plant that are not necessarily built to the same critical standards as the core/primary and containment systems. We'll have to wait for a final report on the plant's response and the various malfunctions. That so many malfunctions occurred is worrisome.

3. As with any human-based system, there are 'human factors' involved, and one of those could be complacency, which the industry has to struggle with all the time.

We'll just have to wait for the report and findings.
 

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