Lessons LearnedProblems following the earthquake and the tsunami came hard and fast, but I decided that there are probably two root causes that could be lessons learned. My two lessons are:
- upgrading emergency preparedness, especially back-up power
- preventing hydrogen explosions.
- preventing hydrogen explosions.
There are huge problems at the fuel pools, and fuel pools are clearly another area for improved management. Still, if the Japanese reactors had had available back-up power and if they had been able to prevent hydrogen explosions, the fuel pools would have been fine.
I will try to cover back-up power, hydrogen explosions, and fuel pools in some blog posts. I'm starting with the easy one today: hydrogen explosions.
Hydrogen Explosions
During Three Mile Island, there was concern with a "hydrogen bubble." Therefore, preventing hydrogen explosions was addressed in this country in a major retrofit effort in the 1980s. Among other things, the NRC ordered American reactors to be retrofitted with special vents to prevent hydrogen from accumulating in the reactor buildings. These hardened vents are designed to vent hydrogen into the atmosphere in an emergency. Vermont Yankee and all other American reactors have them.
I don't know if the Japanese reactors were also retrofitted with hardened vents. A New York Times article today describes the current state of knowledge about the venting. It seems that the Japanese reactors were not retrofitted.
Missing Information?
The news came this morning that containment may be breached at Unit 3 and workers were contaminated in the turbine room with radioactive water. I do not know what this means, but I think NEI Nuclear Notes blog Friday Morning Update has the best description so far.
So far, we have had very contradictory news from Japan. For a while, it looked like containment was breached at #2. Then, it wasn't. Now, it looks like containment may be breached at #3. The fuel pools at #3 and #4 seem to take turns being the major problem. It's hard to follow and pretty much impossible to blog about.
We keep getting news, but it is constantly changing. Nobody in Japan seems to be aggregating it. For example, I have heard that the following things happened at the Fukushima complex:
- One man was killed in a crane, during the initial earthquake
- Three men were hospitalized later for radiation exposure
- Four men were hurt in one of the explosions
- Two men were missing after the tsunami
- Three men had beta burns from radioactive water
"With the three men contaminated by radiation at Fukushima 3 this morning, our injury total at the reactor complex has risen to (fill in the blank)" etc.
However, obviously Japan is in shambles, because other areas are equally opaque. A hydro power dam burst and obliterated 1800 homes, but only "according to some reports." I have seen scattered articles on this dam, but very few. For example, I saw this article in the trade press for hydro power. What happened at that dam?
Similarly, Chiba refinery burned for ten days (or more) with very little coverage, and no word of any injuries or deaths due to the fire. An early video of the fire is below. It wasn't a teeny-tiny fire. You would think we would have heard more about it.
My Conclusions
I will attempt to blog about what I know about the Japanese situation, always remembering that I know very little.
Fukushima photo, 1975, from Wikimedia Commons. Made based on [http://w3land.mlit.go.jp/WebGIS/ National Land Image Information (Color Aerial Photographs)], Ministry of Land, Infrastructure, Transport and Tourism
9 comments:
Meredith, the main energy issue in Japan is lack of energy:
http://news.sciencemag.org/scienceinsider/2011/03/quake-question-11-what-is-the.html
I read somewhere that the number of deaths was small from the hydro break, but couldn't find it just now, somewhere in the single or low double digits if I remember correctly.
And I think the man in the crane is ignored because he died before the plants started having problems. But I don't know.
Good luck figuring out what is happening.
this is very earnest account -
I heard this morning that Greenpeace
were also sending a radiation monitoring team - I think pro or anti-nuclear - the situation is grave-
I feel that there is a place for impartial international monitoring of
health, safety and enviromental concerns regarding the Nuclear Industry..where the liabilty for crisis management is rests internationally and is not the sole responsibilty or juridiction of the country affected. This way it may be possible to deal stratigically and transparently..I wondered whether you had an opinion on this.
With regards
Cate Murray
Thank you for your comments.
Yes, Karen, the main problem in Japan right now is that people don't have heat, electricity, and food. Sometimes I think even wanting to know more about Japan is selfish. After all, why should the Japanese spend any time informing people when they have so many direct, immediate problems? Other times I am deeply annoyed at the fact that HUGE events happen with almost no information released.
I agree Cate that more than one nation should be involved. America has sent nuclear-expert teams and radiation monitoring teams. At the website below, you can get slide shows of American radiological monitoring in Japan on March 22 and 25. It's a blog, so the March 22 data is below the March 25 data. Both slide shows can be downloaded.
http://blog.energy.gov/content/situation-japan/
Another note. I will rarely publish anonymous comments in the future. If they contain some information to share, I may publish them. If not, they go into the bit bucket. With all the new blog traffic about nuclear, several other bloggers have also had to be firmer in acting upon the statement that many of us write above the comment field: "anonymous comments are strongly discouraged on this blog."
Why didn't they blow down.
You'd need a emergency power source like a diesel generator on the roof and a means to vent reactor steam to an outside stack.
At worst you need about 400 gals a minute to feed the core...
God knows how long you could have lasted with the water in the mcond and the torus.
Then you could have refilled the torus if it got low... with low pressure water
MIke, I don't know how they made their decisions, and I don't know enough about operations to say anything really solid here. Thank you for the comment.
As I understand it, all the diesel generators were in the basement where the switchgear got ruined by the tsunami.
Yea, RCIC is 400gal/min...that is about a half a million gal a day.
I used to work for one of the mega power A&E’s back in the day (fossil side) and my college roommate, who also worked there (nuclear side), mentioned to me that there were something like little spark plugs on the ceiling’s containment that were regularly or continuously energized to burn off accumulations of hydrogen gas. Is this true and how would that effect what we saw at Fukushima?
Deckland. As I understand it there are hydrogen igniters at various places in containment. Howard knows more about this than I do. I have heard them described as like diesel igniters. However, they do not work without electricity. The fundamental cause of so many problems was lack of electricity.
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