Sunday, March 20, 2011

Better Or Worse?

We now have the definitive word on the current status of the Japanese nuclear reactor problems. Things are getting better but they could get worse. Isn't that the way life always works?

So how about better?

Japan took a step toward possibly getting its nuclear disaster under control Sunday as electricity to power some reactor cooling systems was restored and previous efforts to lower reactor temperatures with seawater at the battered Fukushima atomic energy plant appeared to have had an effect.
And now for the bad news:
...increased optimism by Japanese officials and Western scientists alike was tempered by a newly emerging crisis -- radiation contamination was found in some food and water supplies in a nation already suffering from a cascade of troubles.

Although Japan's Health Ministry said the contamination levels were not immediately harmful to humans, the discovery of higher-than-normal radioactivity in batches of milk and spinach -- and of traces of radioactive iodine in tap water in Tokyo and elsewhere -- stirred new angst in a public already weary from earthquake aftershocks, blackouts and the threat of a full-fledged nuclear meltdown.
The contamination is not serious so far. The levels are supposed to be such that if you ate the contaminated food for a year it would be equal to a CT scan.

The physical consequences for the US are going to be very mild even in the worst case (and uncontrolled criticality accident). The economic consequences will be more severe. Physically Japan and the Japanese are suffering terribly and that is without the nuclear accident to contend with. Give what you can to the charity of your choice. Even a rich country can have cash flow problems in an emergency.

Update: 20 March 2011 1455z

This may or may not be new bad news. It is definitely bad news.
Edward Morse, a professor of nuclear engineering at the University of California, Berkeley, added that it will take huge amounts of water to compensate for the cracks in the containment pools that were uncovered by U.S. surveillance aircraft on Friday.

"The best thing to do is use as much of the Pacific Ocean as possible," he said.

Not only will water absorb heat, it also forms a protective barrier against radiation, making it safer for workers at the plant, said David Lochbaum, a former nuclear plant operator and head of nuclear safety policy at the Union of Concerned Scientists.

"If they can cover the fuel, it will reduce the radiation levels and they can use the plant equipment," Lochbaum said.

If the fuel overheats, as it has already done in some cases, it will release additional radioactive contamination into the environment.

That possibility, which the plant operator said could not be ruled out, would destabilize the situation further and vastly complicate future efforts to clean up the plant.

While the spraying continues, workers continue to be exposed to relatively high levels or radiation, with doses of 20 millisieverts per hour measured in the control room at the site.
That is about 3 years of an average first world radiation dose (including X-rays etc) in one hour. Not instantly lethal by a long shot. But definitely dangerous. And that is not all we have to worry about:
The French nuclear agency IRSN said Friday that Fukushima had already released 10 percent as much radioactivity as Chernobyl, but the agency has been criticized for being alarmist.
Well of course. And suppose it was only 1% of Chernobyl? Just great.

And just to blacken the rest of your Sunday:
Company workers were able to lay a new power line to the plant early Saturday morning and began connecting it to reactor No. 2, whose containment vessel is believed to be cracked. They will then hook up the buildings housing reactors No. 1, No. 3 and No. 4, which they hope to have connected by the end of Sunday, they said.

But experts think it is unlikely that cooling pumps in the three reactors that were operating when the magnitude 9 Tohoku quake struck will work even with an outside source of electricity. Those pumps were probably damaged in a series of hydrogen explosions that occurred in the first four days of the crisis. The power lines could provide needed electricity to valves and controls, however.
Assuming the wiring and devices are intact following the earthquake and tsunami. Given that they would all have to be checked out as well as possible by guys in moon suits - I'm not optimistic. Checking stuff in shirt sleeves is difficult enough.

It is not over.

And if the pumps don't work? Well it is back to water injection + venting. Charlie Foxtrot.

Cross Posted at Classical Values

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