Japan Earthquake: nuclear plants

Astronuc

They just had a mag 6.2 down near the Tokai plant.
http://earthquake.usgs.gov/earthquak...usc0002nzx.php
Date-Time:
Monday, April 11, 2011 at 23:08:16 UTC
Tuesday, April 12, 2011 at 08:08:16 AM at epicenter

Location: 35.406°N, 140.542°E
Depth: 13.1 km (8.1 miles)

Distances:
77 km (47 miles) ESE of TOKYO, Japan
82 km (50 miles) E of Yokohama, Honshu, Japan
106 km (65 miles) S of Mito, Honshu, Japan
140 km (86 miles) SSE of Utsunomiya, Honshu, Japan

shogun338

RPV temperatures remain above cold shutdown conditions in all Units, (typically less than 95 °C). In Unit 1 temperature at the feed water nozzle of the RPV is 228 °C and at the bottom of the RPV is 121 °C. In Unit 2 the temperature at the feed water nozzle of the RPV is 149 °C. The temperature at the bottom of the RPV was not reported. In Unit 3 the temperature at the feed water nozzle of the RPV is 92 °C and at the bottom of the RPV is 111 °C. With the temperature being over 428 degrees Fahrenheit at the feed nozzle does this indicate that fission is still occurring inside Unit 1 ? http://www.iaea.org/newscenter/news/...iupdate01.html

SredniVashtar

They have raised the level to 7
http://www.bbc.co.uk/news/world-asia-pacific-1304534

Japanese authorities have raised the measure of severity of their nuclear crisis to the highest level, officials say.
The decision was taken due to radiation measured at the damaged Fukushima Daiichi power plant, NHK reported.
"This is a preliminary assessment, and is subject to finalisation by the International Atomic Energy Agency," said an official at the Nuclear and Industrial Safety Agency (NISA)
The decision to raise the threat level was made after radiation of 10,000 terabequerels per hour had been estimated at the stricken plant for several hours.

Astronuc

The temperatures on Unit 1 are puzzling, and the Unit 3 temperatures are problematic.

I_P

An interesting article providing some details of the first two days of the accident:

http://www.yomiuri.co.jp/dy/national/T110411004567.htm

Bodge

Confusion reigns in Japan:

11:14 NEWS ADVISORY: Radioactive materials from Fukushima plant 10% of amount from Chernobyl

11:39 NEWS ADVISORY: Fukushima different from Chernobyl, without massive radiation leak: agency

12:09 NEWS ADVISORY: Radiation leak may exceed amount in Chernobyl accident: TEPCO

http://english.kyodonews.jp/news/

JustGuessing

Astronuc,

Thank you so much for all the information you have supplied during this past month.

This forum has been invaluable as I struggle to understand what all the data, and corrected data, and crazy theories, mean to everyone living near the nuclear plants -- and the future of nuclear power.

Your insights are great. And now I must also thank you for saying when the data points are simply puzzling. Sometimes the explanation is not clear...hopefully we'll get more data soon that will help us understand the situation on the ground better.

-- JustGuessing

P.S. A month in, how do you think they are doing? What are you most concerned about? C an you start to image the cleanup?

liamdavis

With respect to this the information contained in this report.

"

When I worked on the construction of Pilgrim 1 in 1970 the diesel generators were radiator cooled, each had six starters, each starter had its own energy source and on site was a minimum of six months of fuel. In other words it was independently self sufficient, as an emergency system should be.

The system described in the publication above sounds like back up power for convenience. It was dependent upon, and assumed the the continued operation of, systems external to itself "sea water pumping and cooling system" for any operation.

I can understand a sea water-to-coolant heat exchanger in addition to a water-to-air heat exchanger, but not instead of it. I am,of course, assuming that the design purpose is the protection of human life.

I maintain commercial aircraft and I would not want to be responsible for maintaining anything designed by people who thought out the emergency(?) power system at Daiichi.

shogun338

Emergency Preparedness and Response to Radiation . What Preparations Can I Make for a Radiation Emergency
Your community should have a plan in place in case of a radiation emergency. Check with community leaders to learn more about the plan and possible evacuation routes. http://www.bt.cdc.gov/radiation/emergencyfaq.asp

shogun338

How close are you to a nuclear plant ? Are you in the 50-mile exclusion zone ? This map will show you how close you are in case of an accident . http://d3fjco7hozu03c.cloudfront.net/index.html

AntonL

Confusion reigns in Kyodo,

13:01 URGENT: Radiation leakage may eventually exceed that of Chernobyl: TEPCO

Cire

All these temperature sensors where cooked (ie. Damaged). They greatly exceeded their operating temperature. I don't believe these numbers are accurate. The feed nozzle is the point where the cold water is being injected and has probably the highest temperature drop because of the flow rate and temperature difference.

If these temperatures where accurate we'd be seeing the steam equivalent of 8 cubic meters of water per hour pouring out the reactor somewhere. Not cold water leaking into trenches and pouring into the ocean.

The feedwater temperatures being reported are very close to what you see when the reactor is running. You can read more about these measurements and how you can get gradients in the plumbing here: LINK

Cire

I'm about 12 miles from a plant. I get a free packet of Potassium Iodide in the mail each year. I also keep my dosimeter and Geiger counter running

I'm glad the plant is there, even knowing the risks.

sp2

P.S. One more question:

I've been asking this of various people in various places for a couple of weeks now, and I've yet to hear a convincing answer: If the reactors shut down on March 11, and the half-life of I-131 is 8 days, and we were assured, therefore, by every Pompous Nuclear Pundit from Day 1 that the Iodine was a transient problem that would disappear in a jiffy... why is it that we're still seeing so damn much I-131, everywhere we look, what, FOUR half-lives out, now??

What gives? How many half-lives do we have to go, before someone starts to wonder what the hell is going on?

Forgive me if there's an obvious explanation for this, but I'm really having a hard time seeing it.
(If it *is* just a case of normal decay of the initial products, then what the heck does that say about the quantities that were originally released? They'd have to be pretty huge, no?)

Thanks again.

shogun338

Map of Radiation Measurements by Greenpeace team http://maps.google.com/maps/ms?ie=UT...9&source=embed

shogun338

I'm 20 miles from Plant Hatch in Georgia and receive no Potassium Iodide and no alert radio . My relatives that live closer to the plant receive all that . I think they should expand the zone considering the event in Japan . There are dozens of towns in this area that would be affected in a accident at the plant such as a fire in the spent fuel pool . I have a lot of friends that work in the plant that are glad its there too. I know we need nuclear energy but we all need to ensure it it made safer .

Bodge

After 2 weeks without a report, the sensor at the bottom of reactor 2's RPV is showing 208.1C

http://www.meti.go.jp/press/2011/04/...10412002-3.pdf

http://atmc.jp/plant/temperature/?n=2

This is the highest reported temp at that location.

Also, possible context via Kyodo, 12:22 12 April

Discuss!