The Japanese government said early Wednesday [local time] that a fire was burning at the No. 4 reactor in the Fukushima Daiichi nuclear complex in northeastern Japan.
Officials of the Tokyo Electric Power Company (Tepco) said they were considering two alternatives to cool spent uranium fuel rods that are in what The Times described as "a boiling rooftop storage pool." The first idea is to use helicopters to spray cold water on the rods from above; the second is to inject cold water from below. The cause of the fire is currently unknown, at least to the news media.
The spent fuel rods stored in the rooftop pool are still radioactive and could easily become as dangerous as the fuel rods inside the reactor if they are allowed to overheat. It is critical that the rods remain submerged in cool water.
On Tuesday morning, hydrogen gas from chemical reactions triggered by the hot spent fuel rods at reactor No. 4 caused an explosion that blew a 26-foot-wide hold in the outer building of the reactor. Officials are also concerned about storage pools and spent fuel rods at reactors No. 5 and No. 6.
None of those three reactors were operating when the 9.0-magnitude earthquake struck on Friday afternoon, damaging cooling and containment systems throughout the nuclear complex, followed by a tsunami with 30-foot waves that stormed in minutes later and swamped the site.
At least 750 workers were evacuated on Tuesday morning after an explosion damaged the inner containment building at reactor No. 2, releasing a rush of radiation 800 times more powerful than the "safe" hourly exposure limit set by the Japanese government.
A skeleton crew of 50 workers stayed behind in a heroic effort to keep seawater flowing to reactor Nos. 1, 2 and 3, where overheated fuel rods evaporate the cooling water almost as fast as it arrives. The 50 workers, who are being repeatedly exposed to dangerous levels of radiation, take shelter as often as they can in the heavily shielded control room.
Meanwhile, hundreds of thousands of Japanese citizens have been evacuated from the region around the Fukushima Daiichi nuclear complex or confined to their homes by the Japanese government, which has the Nuclear Regulatory Commission and the International Atomic Energy Agency for their help managing the crisis.
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[1]The economies of the indstrial countries depend on cheap, readily available energy.
[2]All engineering solutions entail compromises between the conflicting factors, risks vs benefits.
[3]Petroleum & coal are being depleted at a rate that will see mthem gone withiin a century.
[4]Wind & solar sources are too expensive and unreliable to serve as adequate replacements for fossil fuels (the wishful fantasies of the TreeHuggers notwithstanding).
Given the potential for disaster in the recent events in Japan, we should be encouraged by the design and construction of their nuclear plants. They were strong enough to withstand the pounding of a 9.0 earthquake (a once in 1000 yr event) and of the amazingly forceful tsunami. The plants integrity remained intact. The problem was caused when the generators providing power for the cooling pumps were water damaged. That’s a problem unforeseen, but now remediable in future plants.
Nuclear “accidents” are amazingly mild in their health complications. Exactly ZERO problems were encountered after Three Mile Island, and only 50 excess deaths after Chernobyl- a plant designed, built and run by amateurs. Remember that thousands of coal miners have lost their lives in accidentsin the past century.
Given that legal delays by uneducatd obstructionists cause new nuclear plants to take 40 yrs (!!!) to be completed, any slowing down of the construction process should be avoided. Should new problems come to light, plans can be adapted quickly enough.
The economic and social chaos and hardship resulting from lack of good energy sources will far outweigh the risks of this technology.
Let’s have a better look at Chernobyl shall we? Guido says “only 50 excess deaths” but according to the IAEA report around 600,000 people were exposed to dangerous levels of radiation and 4,000 thyroid cancer deaths in that exposed population. Those numbers are not mild in any way. Plus you have other consequences to look at such as infertility and human developmental defects that aren’t deadly but have a severe impact on the quality of life of the people exposed. Guido makes a good point though, about coal miners dying in mines, and there is no perfect solution and nothing is without risk. I’ll also agree that nuclear accidents are rare, but time is the enemy of probability in this case and the more we depend on nuclear fission for power the more risk we take on. I’m not arguing for or against a nuclear future, I just want people to know the full risk of this technology without glossing anything over.
Just a follow-up note: news sources claimed that people in towns immediately around the damaged Japanese nuclear plants are being exposed (as of 3/17) to 3.5 uSv of radiation per day. For easy arithmetic, call that 1000 uSv/yr. The minimum radiation exposure known to cause cancer is 100 mSv. Therefore, if there were no dissapation of the spilled radiation over time, it would still take a person 100 yrs to accummulate a damaging dose at this rate.
I agree completely with your conclusions, Czero. Your numbers on Chernobyl may be a bit inflated: http://en.wikipedia.org/wiki/Chernobyl_disaster#Assessing_the_disaster.27s_effects_on_human_health
Knowing how damaging radiation can be, I’m amazed at the paucity of health damage done at Chernobyl, TMI and even Nagasaki/Hiroshima: http://www.ncbi.nlm.nih.gov/pubmed/18300710
http://www.solarstorms.org/Hiroshima.html
This is not to ignore the dangers, but to put them into a scientific, not emotional perspective.