. Earth Science News .

New fission suspected at Japan nuclear plant
by Staff Writers
Tokyo (AFP) Nov 2, 2011

The operator of Japan's tsunami-crippled Fukushima nuclear power plant said Wednesday it feared nuclear fission had resumed inside one of the reactors.

Tokyo Electric Power Co. (TEPCO) said it had begun injecting water and boric acid into Reactor No. 2 at the Fukushima Daiichi plant, which began leaking radiation after the March 11 earthquake and tsunami.

"We cannot deny the possibility of a small nuclear fission reaction," TEPCO spokesman Hiroki Kawamata said, adding that the injection was a precautionary measure.

He said there was no fresh danger at the plant, as the reactor's temperature and pressure, as well as radiation levels at monitoring posts, showed no substantial changes.

Fission is the process by which an operating nuclear reactor produces power.

The reactor automatically shut down in the wake of the disaster but nuclear fuel is believed to have melted through its container onto the bottom of the outer vessel when the tsunami knocked out the plant's cooling systems.

The injection was ordered after preliminary analysis of gas samples from the reactor building showed the possible presence of xenon 133 and xenon 135, byproducts of a nuclear reaction.

The two substances have short half-lives -- five days for xenon 133 and just nine hours for xenon 135 -- indicating that any nuclear fission was a recent phenomenon.

"Considering the half-life of xenon 133 and 135, we believe nuclear fission may have occurred in the recent past," said Junichi Matsumoto, TEPCO official in charge of nuclear operations.

There is a possibility that criticality, a self-sustaining nuclear chain reaction, occurred temporarily, Matsumoto said, but added it would not have been long enough to pose any risk.

The temperature at the reactor No. 2 had been brought to below 100 degrees centigrade (212 Fahrenheit), TEPCO said, one of the conditions for the utility to declare so-called "cold shutdown".

The possible fission "has no major impact on the reactor's state of being cooled down," Matsumoto told a news conference.

Technicians have been battling since the tsunami to achieve cold shutdown of the reactors, a stable condition in which temperatures drop and no reaction takes place.

Related Links
Bringing Order To A World Of Disasters
A world of storm and tempest
When the Earth Quakes

Get Our Free Newsletters Via Email
Buy Advertising Editorial Enquiries


. Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Japan lawmaker drinks water from Fukushima plant
Tokyo (AFP) Nov 1, 2011
A Japanese lawmaker has drunk a glass of water taken from a radioactive puddle inside a reactor building at the stricken Fukushima nuclear plant in a bid to prove decontamination efforts are working. Television footage showed a visibly nervous Yasuhiro Sonoda gulping down water that he said had been decontaminated after being scooped up from inside the plant. "Just drinking (decontaminat ... read more

Evacuation after ammonia leak at US nuclear plant

New fission suspected at Japan nuclear plant

Purdue quake expert returns to Turkish homeland to assess damage

Japan lawmaker drinks water from Fukushima plant

News Corp. net profit down five percent

Google expands online bookstore to Canada

Spin lasers in the fast lane

An important aspect of structural design of super-tall buildings and structures

Suggested Explanation for Glowing Seas

An analysis of water discourse over 40 years of UN declarations

Fog harvesting gives water to South African village

Seaweed records show impact of ocean warming

New webcam allows world to watch live polar bear migration

Campaigners push for vast Antarctic marine reserve

A Crack in the Pine Island Glacier Ice Shelf

Scientists Predict Faster Retreat for Antarctic Thwaites Glacier

Cambodian floods spark shortage of rat meat: PM

Farming Australia takes on China Inc.

Crop sensors outdo farmers at choosing nitrogen rates

For land conservation, formal and informal relationships influence success

Electrocution warning as Thai flood toll spikes

Arabian cyclones intensified by S. Asian pollution: study

Floods divide on-edge Thai capital

Thai officials on defensive as flood anger mounts

Kenya claims Somali rebels receive third weapons airdrop

Japan to send nation-building troops to S.Sudan

Nigerian military mop up arms in restive city

Kenyan raid kills three civilians in southern Somalia

Shared genes with Neanderthal relatives not unusual

Commuting - bad for your health

Our brains are made of the same stuff, despite DNA differences

Seven billion people are not the issue rather human development is what counts


The content herein, unless otherwise known to be public domain, are Copyright 1995-2011 - Space Media Network. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement