At Fukushima nuclear plant, concern and confusion over state of #3 reactor

RTR2KD5D.jpgClick for larger photo. Japan Self Defense Force members in protective clothing prepare to transfer to another hospital workers who were exposed to radiation at Tokyo Electric Power Co.’s Fukushima Daiichi Nuclear Power Plant, at a hospital in Fukushima Prefecture, northeastern Japan on March 25, 2011. About 300 engineers have been working around the clock to stabilize the six-reactor Fukushima complex since an earthquake and tsunami struck two weeks ago. (REUTERS/Kyodo)

Two of the six reactors at the Fukushima Daiichi nuclear power plant are now in cold shutdown. That’s the good news. The bad news is that Reactor #3, the one that uses recycled fuel, isn’t one of them. In fact, it’s giving people in Japan some new worries.

The temperature and pressure in the core of that unit are stable now, and the temperature is low enough that the core shouldn’t melt any more than it already has, according to the AP. But three workers were burned yesterday when they were exposed to very high levels of radiation in contaminated water, which they’d had to wade through as part of the work of keeping Reactor #3 under control. The doses they received are high, but well below the World Health Organization’s limit for worker exposure during emergency situations.

The cause of those elevated radiation levels is the source of a lot of confusion and concern right now. There are several possible causes, but the one that’s got people worried is this: The elevated radiation levels in that water could be a sign that there’s a physical crack or hole in one of the layers of steel and concrete surrounding either the core, or the spent fuel pool. If that is actually what has happened, it would mean that a lot more radiation is likely to be released compared to what we’ve already seen, and it would also likely mean that the groundwater has been contaminated.

It’s really hard to tell what’s going on exactly. The AP and Reuters are giving slightly different accounts of the same information. World Nuclear News says that the fact that pressures and temperatures are stable in Reactor #3 is evidence that the containment probably hasn’t been breached. But, again, they’re a potentially biased source.

It’s a little weird for me to pop on here and tell you that I don’t really know what’s going on. But I think it’s also important to do just that. When the information available isn’t as clear, cut-and-dry as the headlines make it sound, you need to know about that. In a nutshell, here’s what we do know: There are higher-than-expected radiation levels in one part of Fukushima Daiichi #3. Nobody knows what’s causing it yet, but they’re working on figuring it out. One of the several possible answers—a breach of the core—would be very bad. Hopefully, that’s not what’s going on.