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