There is a lot of confusion and conflicting information coming out of Japan right now, but I’m glad to say that the nuclear situation has not deteriorated overnight as much as I feared. The power company says the containment has suffered no significant change as a result of the most recent explosion, which is very welcome news. Twenty-three workers at the plant have had to be decontaminated, but the “heightened” levels of radiation seen in the metropolitan areas are still minute and not dangerous. To illustrate how much confusion there still is: There have been conflicting reports as to whether the radiation levels reported at the plant are in millisieverts or microsieverts (the latter is a thousand times less dangerous), little indication as to whether heightened radiation levels at the plant are around the reactor or outside the reactor structure, and no strong indication whether they derive from venting of gases that are easily dispersed and carry no long-term hazard, or from aerosols of cesium and iodine, which are indeed problematic.
It is becoming clear, however, that the biggest problem has been the lack of backup power — the tsunami destroyed the on-site diesel-powered plants. Attempts to get in more emergency power have been faltering at best, leading to the coolant problems that have led to the potential/partial meltdowns (I am still unclear whether meltdown has actually taken place). As such, it is a failure in a second-order safety feature that has led to the problems. I am unaware of any other incident in which backup power has failed for so long, but the circumstances in which it did remain extraordinary.
So when the New York Times says this —
With the United States poised to expand nuclear power after decades of stagnation, it will be important to reassess safety standards. Some 30 American reactors have designs similar to the crippled reactors in Japan. Various reactors in this country are situated near geologic faults, in coastal areas reachable by tsunamis or in areas potentially vulnerable to flooding. Regulators will need to evaluate how well operators would cope if they lost both primary power and backup diesel generators for an extended period.
This page has endorsed nuclear power as one tool to head off global warming. We suspect that, when all the evidence is in from Japan, it will remain a valuable tool. But the public needs to know that it is a safe one.
— I think they have got it broadly right. The sort of checks they are talking about should not take too long. Backup power facilities may need to be strengthened in some cases, but I see no reason for this to interfere with the normal running of the plants. Future design will certainly take backup power into account. The events in Japan as yet provide no reason for America to abandon its nuclear program. Let us reiterate what has so far resulted from this second-worst nuclear-power incident ever:
• Zero deaths from radiation.
• Zero release of radiation levels of a danger to human health, except for brief periods for those working within the plant compound (not Public exposure). These workers would be well protected and monitored to avoid excessive accumulated doses.
• Minimal injuries (about a dozen) as a result of the hydrogen explosions.
• No significant or lasting environmental impact whatsoever.
• A major evacuation, which has no doubt been distressing for all involved.
• 8–10 of Japan’s 55 nuclear reactors known to have varying levels of damage that will impact their ability to provide electricity. The remainder will no doubt require inspection, but would appear to be relatively undamaged.
When the Times says that “the public needs to know” nuclear power is safe, that is Steven Chu’s job. I repeat my question: Where is he?
Finally, we should note that there was also a renewable-energy disaster in Japan, but it has so far gone unreported, except in the trade press:
A dam in the Fukushima prefecture of Japan was breached following the recent earthquake and tsunamis which have devastated the country.
According to media reports, the dam broke on Friday, with a wall of water washing away 1800 homes downstream.
I have not noted the usual suspects calling for all hydroelectric dams to be shut down, or even for an urgent review of their safety.