UPDATE 4-Japan declares emergency at nuke plant, no radiation leak now

Reuters ^ | March 11, 2011 | Osamu Tsukimori and Kiyoshi Takenaka

[americanophile]

* Problems not at critical level -local officials quoted

* U.S. Air Force delivers coolant to nuclear plant

* Thousands of residents evacuated as precautionary measure (Adds researchers' quotes, background)

TOKYO, March 11 (Reuters) - Thousands of residents were evacuated from an area around a nuclear plant in Japan after a powerful earthquake raised fears of a radiation leak, but local officials said problems with the reactor's cooling system were not at a critical level.

There were no signs of a radiation leak, but the U.S. air force delivered coolant to the nuclear plant to avert a disaster within the wider disaster of the biggest earthquake on record to hit the country.

Experts said there could be leakage if water levels in the Fukushima reactor -- some 240 km (150 miles) north of Tokyo -- fell and the temperature of the nuclear rods rose, but that this danger did not appear to be imminent.

[americanophile]

Live info here: http://live.reuters.com/Event/Japan_earthquake2

Another quake just hit 6.6 magnitude.

[Raebie]

Look at all of the activity in that same spot leading up to the big one.

http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.html

[Raebie]

That one was in Tokyo?!?

[driftdiver]

So the Air Force delivered water?

[mmercier]

The USN is delivering coolant to the facility at this moment in time. An unprecedented thing.

They are looking at a Chernobyl type incident. They are currently venting low level coolant steam into the atmosphere.

[The_Victor]

For the record, nuclear reactor coolant is water.

[Drill Thrawl]

The USN is delivering coolant to the facility at this moment in time. An unprecedented thing.

It's only unprecedented when Obama lends support to an ally. Then again the current PM is too big on America.

[Hardraade]

Ummm, not quite that for the core. If they had to have outside supplies, that would be heavy water.

[cornfedcowboy]

Are you sure it isn’t Prestone?

[ichabod1]

merely an aftershock.

[ichabod1]

not the really important coolant.

[americanophile]

Well, apparently there are Water cooled reactors, Liquid metal cooled reactors, Sodium-cooled fast reactors, Lead-cooled fast reactors, Gas cooled reactors, Molten Salt Reactors, etc. I don’t know what kind of reactor is at issue in Japan and what coolant has been delivered.

[americanophile]

No, apparently it's a new earthquake on a different fault in another region. Related, but a separate event.

[rsobin]

Isn’t h2o a poison in a d2o reactor hence further reducing fission?

[americanophile]

No, apparently it's a new earthquake on a different fault in another region. Related, but a separate event.

[azkathy]

All of the activity since the 8.9 is amazing. Prayers up for Japan-it has to be very frightening for them.

[aumrl]

BORON

[BlazingArizona]

“They are looking at a Chernobyl type incident. “

Fukushima is a boiling water reactor, which is an old-school design, but not a Soviet RBMK. If it melts down it will be within containment.

[The_Victor]

Japan uses the same inherently stable reactor design that the US uses: water coolant. The water also drives the reaction by slowing neutrinos and reflecting them back into the reaction. Without the water in the reactor core the reaction dies out.

[HereInTheHeartland]

It’s a battle for control it sounds like:

http://www.reuters.com/article/2011/03/11/us-japan-quake-reactor-idUSTRE72A2NR20110311