Nuclear emergency declared at quake-damaged reactor

[googlegoogle]

http://www.usatoday.com/news/world/2...reactors_N.htm

[Dave Lane]

Originally Posted by Dante84

Jesus.

Change the ****ing thread title, jackass.

He really would have had a shot at beating Tom at douchebag of the year.

[Tribal Warfare]

Originally Posted by RJ

and they are honestly making an american made reboot of Godzilla also

[mikey23545]

"No Chernobyl is possible at a light water reactor. Loss of coolant means a temperature rise, but it also will stop the reaction," Naoto Sekimura, a professor at the University of Tokyo, said.

"Even in the worst-case scenario, that would mean some radioactive leakage and equipment damage, but not an explosion. If venting is done carefully, there will be little leakage. Certainly not beyond the 3 km radius."

Dumbasses.

[DaFace]

Huh. Apparently, an attempt to restrict his privs further somehow overrode the ban on thread starting abilities.

[teedubya]

[Dave Lane]

Originally Posted by DaFace

Huh. Apparently, an attempt to restrict his privs further somehow overrode the ban on thread starting abilities.

Miserable User. Ohhh pllleeeaaaasssee!!!

[teedubya]

Just curious, does anyone know the best place to get a forecast for the jetstream? I can't figure it out on Intellicast.com

EDIT:

[ReynardMuldrake]

Stole this from Reddit:

Disclaimer: IAaNRO (I Am a Nuclear Reactor Operator. I work part-time at my college's research reactor)

Short Answer: It's unlikely. It's been shutdown, but the core is still producing heat. It's not impossible for it to meltdown, but the main concern right now is that the steam pressure is rising in the cooling system, to the point where the system might rupture if nothing is done.

(Note: Originally I thought it was impossible for this reactor to meltdown at this point, but I've since been corrected. I've edited my answer slightly to reflect this)

Long answer:

Nuclear power reactors are of two main varieties: Pressurized Water Reactors, and Boiling Water Reactors. The plant in question is a Boiling Water Reactor (BWR). BWRs work by using the core's thermal energy to boil the cooling water into steam, and then channelling the steam in order to turn a steam turbine. After it exits the turbine, the steam is cooled in a condenser, where it turns back to water, and then is sent back into the core. The condenser requires cool water to be actively pumped through it, to keep the pipes upon which the steam condenses from becoming too hot. The water/steam that runs through the core and the turbine is referred to as the "primary cooling system", and the water running through the condenser is the "secondary cooling system." The primary is assumed to be contaminated (that is, it is measurably radioactive), whereas the secondary system is not, since it is isolated from the primary.

As far as I can tell, the chain of events for this particular plant went something like this:

Shortly after the quake, the reactor successfully shut down in anticipation of the tsunami. This means that no more fission is occurring in the core. A meltdown a la Chernobyl is a result of uncontrollable fission. This will not be another Chernobyl. However, just because U-235 is no longer fissioning, doesn't mean that the core isn't producing heat. The fission fragments (those isotopes produced as a result of the U-235 fissioning) will continue to decay through alpha, beta, or gamma emission, until stable elements at the bottom of the decay chain are reached. The decay of these fission fragments and their decay products will cause the core to continue to produce heat for some time after shutdown.

Presumably due to the fact that every reactor near the east coast of Japan was being shutdown, offsite power for the secondary cooling system was unavailable, so the power plant had to rely on onsite backup power, but the onsite power only lasted for 8 hours. After that, the secondary cooling system failed, which is what triggered the declaration of the Nuclear Emergency, and evacuation of those living within 3Km of the plant.

Since the core is continuing to produce heat, and consequently steam, the steam pressure inside the primary system is rising above normal levels. They are hesitant to bleed off steam into the containment dome, since the dome was probably damaged in the quake, but obviously bleeding off some steam is better than having the primary system rupture. Thankfully, most of the really nasty decay products have a relatively short half-life. In particular, Nitrogen-16, which gives off pretty high energy betas when it decays, has a half-life of 7.2 seconds. Therefore, releasing the steam is undesirable, but not catastrophic, and probably not even particularly hazardous. The radioactive materials in the cloud will be longer-lived decay products of hydrogen and oxygen in, and as far as I'm aware none of those are particularly active. The cloud will be dilute itself after release, which will lower the intensity of the radiation field significantly. Therefore, the total radioactivity release will be many orders of magnitude lower than that of Chernobyl or Three Mile Island.

So basically, the reactor is offline but overheating due to the power outage, and they may have to vent steam that is mildly radioactive. Very low probability of a meltdown, the evacuation seems to be more of a precaution than anything.

[teedubya]

http://headlines.yahoo.co.jp/hl?a=20...00126-jij-soci


[TRANSLATED JAP TO ENG]

Primary or core meltdown in the discovery of cesium in the vicinity of the first-Hukushima - NISA
Newsletter March 12 (Sat) 11:14 min delivery
　
Nuclear and Industrial Safety Agency Ministry of Economy, Trade and Industry on August 12, the first nuclear power plant damaged by earthquake Toukyoudenryoku Hukuzima East (town Ookuma Fukushima Futaba town) in Unit 1, soluble in hot fuel rods "meltdown" has occurred likely announced.

According to NISA, No. 1 around the detection of radioactive cesium on NIRS team. Cesium is contained in nuclear fuel rods, because of its high melting point, it is estimated that the likely cause meltdown.
　
According to the Safety Agency, said nuclear power plant Unit 1 reactor water level decreased from 12 am. Temporarily exposed surface of the cooling water from nuclear fuel rods were damaged nuclear fuel is a concern.　

http://en.wikipedia.org/wiki/Caesium-137

[ClevelandBronco]

I'll play along, tee.

Here. I superimposed the Chernobyl danger areas in scale over a map of Japan. NOW, CAREFUL, EVERYONE. THE COLORED PART IS CHERNOBYL. NOT FUKUSHIMA. Happy worrying!

[007]

I just want to see Ghidorah.

[FAX]

I'm beginning to feel a little sorry for the Japanese peoples of Japan.

Still, looking at the glass half-full, given the nuclear disaster looming on their island, the next generation of Japanese peoples should be able to put together one hell of a circus.

FAX

[googlegoogle]

Originally Posted by Dante84

Jesus.

Change the ****ing thread title, jackass.

I can't change the title. The mods here ****ed my account up.

[googlegoogle]

http://www.bloomberg.com/news/2011-0...k-reports.html

Reactor exploded.

Hows that Daface. Thanks for the Ban too. You said it wouldn't happen. I got it right.

[CrazyPhuD]

Originally Posted by googlegoogle

http://www.bloomberg.com/news/2011-0...k-reports.html

Reactor exploded.

Hows that Daface. Thanks for the Ban too. You said it wouldn't happen. I got it right.

Please quit spreading false and inflammatory news. You may have an axe to grind here but everyone expects you to maintain some degree of credibility. When the first three paragraphs rejects your entire comment about the 'reactor 'blowing up''. You lose any ounce of credibility. This is NOT DC....if you can't handle that then please do not come here.

First three paragraphs from the article YOU post.....

An explosion near a nuclear power station north of Tokyo destroyed the walls of a reactor building and injured four people. Japanese officials said the reactor may melt down following yesterday’s record earthquake.

Tokyo Electric Power Co., Asia’s biggest utility, said there was an explosion near the No. 1 reactor at the Fukushima Dai-Ichi nuclear power station at 3:40 p.m. Japan time today. Four people were injured and radioactivity levels are rising, spokesman Taisuke Tomikawa said in by telephone.

Serious damage to the container of the reactor is believed to be unlikely, Kyodo News reported, citing unidentified nuclear safety agency officials. Fuel rods at the reactor may be melting after radioactive Cesium material left by atomic fission was detected near the site, Nuclear and Industrial Safety Agency spokesman Yuji Kakizaki said by phone earlier today.