Evacuations, plumes, and pills, oh my...
A high-level American official, the Chairman of the U.S. Nuclear Regulatory Commission, recommends expanding the Fukushima nuclear disaster's evacuation area to a 50-mile radius, or ~3900 square miles (area of circle divided by 2, to include only land area):
"Mr. Jaczko’s testimony came as the American Embassy in Tokyo, on advice from the Nuclear Regulatory Commission, told Americans to evacuate a radius of 'approximately 50 miles from the Fukushima plant' and that 'the commission believed that all the water in the spent fuel pool at the No. 4 reactor of the Fukushima Daiichi Nuclear Power Station had boiled dry, leaving fuel rods stored there exposed and bleeding radiation.' As a result, he said, 'We believe that radiation levels are extremely high...'"When this disaster first began, there was a map of projected nuclear fallout, based on measurements of the Chernobyl plume, at some site that I've forgotten. Interestingly, this map was yanked almost immediately, so it's no longer available, but here's a screen shot:
- New York Times
- screen capture, 18:24PDT, 14MAR2011
I do not vouch for the accuracy of this plume map, and indeed it may be completely bogus as claimed by the government. But, the smoke does have to go somewhere, and if it doesn't reach our homes as smoke particulates, it will bioconcentrate and may end up on our dinner plates instead. The smoke (and smoke to come) may dissipate, but it will not vanish; the radioisotopes being released will do their damage for thousands of years to come. Hopefully for the Japanese, the winds will not shift, because obviously, they are at the greatest risk of all. These winds will rain death; the only question is whose deaths that will be.
- screen capture, live-streamed NHK-TV, 12:06PDT, 16MAR2011
And, a heads-up to those seeking potassium iodide tablets: these may be useful at some point, but not so much for adults. They're more a placebo for most of us. But, check your multi-vitamin container, because you may already be consuming the recommended dose for any applicable catastrophe (150 micrograms, or mcg). It is highly recommended that no one take more than that amount, and no disaster guidelines would recommend taking more. It is certainly not worth wasting your money by buying potassium iodide at inflated prices from disaster-opportunists.
UPDATE 2 - IMPORTANT CORRECTION!
Regarding potassium iodide tablets: There is still not sufficient radioactive iodine reaching California from Japan for anyone to be consuming these tablets.
HOWEVER, I need to correct a big error in what I wrote above, which was based on incorrect information...
The dose of iodine in multi-vitamins is typically 150 mcg, BUT the dose needed for protection in the event of exposure to significant levels of radioactive I-131 is much higher:
The adult dose for such a contamination event would be 130 mg (and 1 mg = 1000 mcg). The dose for children is half or less of what's given to adults.
For complete information, please see the CDC's guidelines:
UPDATE - A map of the travel of a theoretical radioactive plume emitted from the Fukushima Nuclear Power Station in Japan, from New York Times, based on data from Comprehensive Nuclear Test Ban Treaty Organization, assuming the weather of this week:
- composite image of 24-hour intervals from the interactive feature provided by the New York Times, with the addition of elapsed time in hours
The model assumes a radioactive source in the middle range, of 0.1-1.0 baseline (without units), to illustrate the logarithmic reduction of intensity over time and distance. For the hypothetical emission of 1 unit, about 1/100 of that intensity would reach California in about six days, according to this model. The model stops at six days, so no further extrapolation can be made. This model does lend credence to the other plume illustration, shown above.