2011 Japanese Earthquake and Tsunami - News and Analysis

All threads that are locked or marked for deletion will be moved to this forum. The topics will be cleared from this archive on the 1st and 16th of each month.
Locked
Purush
BRF Oldie
Posts: 2445
Joined: 26 Oct 2001 11:31
Location: Loc Muinne

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Purush »

Let us not score self-goals for no reason. There are many things wrong with the Indian system, but we can appreciate/observe the japanese relief efforts without denigrating our own people at this time.
Despite the presence of honorary packees in our midst, India also has lots of brave/selfless people who will put themselves in harms way for their fellow citizens, regardless of political affiliation.
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

From AmberG's post in other thread the Torus failed in one of the plants. "Vital component under the containment vessel." Containment vessel is the Reactor Pressure vessel. If that happened the plant floor would flood. The key is to keep puming water to cool the core.

A Chinese saying goes" Calling thngs by right name is begining of wisdom!"

The plants are BWRs and not PWRs. They are GE origin. France makes PWRs under US license and now their own technology.

So France can contribute technically just as much as Malawi to this issue.
A_Gupta
BRF Oldie
Posts: 12265
Joined: 23 Oct 2001 11:31
Contact:

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by A_Gupta »

Suppiah wrote:http://bellum.stanfordreview.org/?p=3142

The Kamikaze spirit of Japanese shines thru....if it were India the CPM controlled union would declare strike for wage increase...
One report coming out of the nuclear engineering community in Japan and Far East Asia is that the Tokyo Electric Power Company (TEPCO) has discussed, internally, what needs to be done to prevent the last reactor from having a full meltdown. According to the story, they have a list of volunteers within TEPCO willing to go on-site with HAZMAT gear to try and work on separating fuel elements. TEPCO is reportedly refusing to accept volunteers under the age of 50, or who have small children as dependents. The reason for this is that the risk of developing cancer as a result of this kind of work is extremely high. We cannot confirm these rumors, but we encourage major media with resources on the ground to verify this if they can.

We call to mind the words of George Patton in 1947: “All men are frightened. The more intelligent they are, the more they are frightened. The courageous man is the man who forces himself, in spite of his fear, to carry on.”
If such a time comes, may we be infused with the same spirit.
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

I don't uderstand that story. The fuel rods are in a grid at the top of the Reactor Pressure Vessel (RPV). To take them out after lifting the reactor lid needs a crane. The crane is at the top of the ctmt bldg. Its polar crane, means it travels on a circular track. To enter the ctmt bldg there are small man access doors in addition to the main large door/hatch.
And if you take them out they will melt due to decay heat. Hence stored in spent fuel pool using the polar crane.

So how do you physically separate them?

Looks like another BS story about model people.

Its true that rad hazard work is not for young people due to medical reasons.
Amber G.
BRF Oldie
Posts: 9362
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Amber G. »

FWIW: Here is brief summary/update wrt to nuclear power plants .. from what seems to be fairly reliable source-
http://www.world-nuclear-news.org

- Concern is growing for cooling ponds at plant 4,5,6. ( were closed for maintenance (weeks/months) before the earthquakes but as pointed out before cooling process is a long process)
-confirmed damage to Fukushima Daiichi 2
-Torus, Containment shows 'no change'
- Radiation levels on the edge of the plant compound briefly spiked at
8 milliSv per hour but later fell to about a third that.

Radiation -
(Bade gave figures of 400 mSv /(per hour ?) in other post)

Plant sites between 3/4 - peek reached to about 400 mSv/Hr.. very local
dropped to about 11.9 mSV/Hr and dropped to 0.6 mv/hr 6 hours later)

(For perspective LD50 (dose which will kill 50% of the people in 60 days, if not treated) is something like 3000-4000 mSv, less than 1000 mSV has no/negligible immediate effect )

-Almost all people living within 20 kilometres of the plant have already been evacuated and supplied with potassium-iodide pills that will protect them effectively against the effects of iodine-131 that could conceivably be emitted in the future. The pills saturate the thyroid gland and prevent the radioactive iodine-131 from being absorbed, dramatically reducing the risk of thyroid cancers, which are the major potential health effect from the possible progression of the accident.
- 30 Km - stay inside warning issued some time ago.
- (per IAEA) 150 people from around the site have been monitored. The results of some people have been reported and 23 have undergone decontamination
-Containment container:
- TEPCO has evacuated all non-essential personnel from the unit. Fifty of the company's engineers remain to pump seawater into the reactor pressure vessel in an effort to cool it.

- (per Tepco - 5pm local time) primary containment vessel around the reactor and secondary containment provided by the reactor building "show no significant change."

Fire at unit 4, concern for fuel ponds

confirmation of fire burning at unit 4, ( This reactor was closed for periodic inspections when the earthquake and tsunami hit, therefore did not undergo a rapid and sudden shutdown. It was of course violently shaken and subject to the tsunami) Fire fighters noticed "sign of leakage".
( "but we have found out the fuel is not causing the fire.") The fire is now reported extinguished.

IAEA confirms - fire had taken place in the used fuel storage pool. The Japan Atomic Industry Forum's status report said the water was being supplied to make up for low levels)

(BTW, used fuel in cooling ponds require water covering to remove the decay heat (though less after weeks, but still need water)- on one hand it has much bigger area/volume ( than active reactor) to keep it cool but it does contain much much more substance 100s (if not more) tons of fuel so there is lot of heat)

-JAIF reporting that temperatures in the cooling ponds at units 5 and 6 are increasing!

FWIW my (shared by many) perspective -

(NES Level 4 Accident means) Plant is safe (for all practical purposes) and will remain safe except local consequences .. bad for the company that owns the plant, people hurt/killed in blasts, but not for anyone else...).. No radiation related deaths aka Chernobyl.

- The radiation leaks (Sea water steam has to be vented before you fill it with fresh sea water) short lived isotopes (eg N) will not be (practically speaking) of any hazard, Cs, Iodine (because the some core is exposed to sea water) will need local evacuations etc
- Years of cleaning up (treatment of seawater, other water in tanks etc to remove/treat Cs etc from it etc)...dismantling of reactor core (sending it to a processing facility etc)..but after 9.0 earth quake, a small part in the whole scheme.
Lalmohan
BRF Oldie
Posts: 13262
Joined: 30 Dec 2005 18:28

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Lalmohan »

i read that Caesium and Iodine isotopes have very short half lives, and if washed out to sea will die out quickly and not pose a threat... is that correct?
Sanku
BRF Oldie
Posts: 12526
Joined: 23 Aug 2007 15:57
Location: Naaahhhh

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Sanku »

From BBC tweets
http://twitter.com/BBCBreaking

European Energy Commissioner Guenther Oettinger: Tokyo has lost almost all control of events at #Fukushima #nuclear plant, from AFP

I think "things are not as bad as they look" is not quite appropriate
sanjaykumar
BRF Oldie
Posts: 6137
Joined: 16 Oct 2005 05:51

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by sanjaykumar »

In terms of absolute size Japan is still huge...you can sell more advanced products or services in Yokohama than you could in all of Indonesia or Philippines or Thailand perhaps all of them put together.

yeah Tokyo is more economically productive than Canada, Australia, Britain put together.

My worry is fallout over Tokyo. And would 'sophisticated' consumers want to buy Japanese lest it be 'hot'?
SureshP
BRFite
Posts: 256
Joined: 10 Apr 2002 11:31

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by SureshP »

Fukushima reactors are BWR-3 (460MW) design for No 1, BWR-4 (784MW) for No 2-5 and BWR-5 (1,100MW) for No 6. First construction began in 1967 and no 6 in 1973.


A 3d cutaway of BWR reactor

Image

A block image

Image
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

Good graphic that explains the whole process.
sanjaykumar
BRF Oldie
Posts: 6137
Joined: 16 Oct 2005 05:51

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by sanjaykumar »

http://timesofindia.indiatimes.com/indi ... 712629.cms

India keeping a close eye on food item imports from Japan
SureshP
BRFite
Posts: 256
Joined: 10 Apr 2002 11:31

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by SureshP »

It should be POINTED OUT that the radiation level from the exposed nuclear fuel rods within the containment vessel WILL DROP BY A FACTOR OF 10 WITHIN 1 WEEK as long as cooling can be maintained for that period of time. This will happen naturally.
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

What food items does India import from Japan?
Amber G.
BRF Oldie
Posts: 9362
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Amber G. »

Ramana - Long ago (mid 70's?) I visited Nine Mile Point (in upstate NY, GE- BWR in some way similar to the Japan's) (I remember this because some elementary school kids were also having a tour of the facilities and I had a good conversation with them).. heard that last week there was 'electric malfunction' and there were sirens going on (all turned out to be okay)
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

Yes I know Nine mile Point very well. Oswego?
It must be NMP-1 as NMP-2 came about in 80s. Its a different BWR than the ones in toruble now. Its a Mark 3 containment with concrete pool instead of the metal torus.
Electric malfunctions are normal due to line tripping. These are planned for events. It causes a transient in shutting down the plant. So these type led to thermal cycling and hence fatigue loads.
Sanku
BRF Oldie
Posts: 12526
Joined: 23 Aug 2007 15:57
Location: Naaahhhh

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Sanku »

TEPCO seems to have a long and shady history of "face" saving actions

http://timshorrock.com/?p=1113

In 2002, Tokyo Electric Co. admitted to falsifying its records of nuclear inspections and hiding the facts for more than a decade. Ironically, the information came from a whistleblower at GE, which helped build the plants and has contracted with TEPCO on operational matters for decades.

Karma is indeed a female dog, and she does not care for face.
Amber G.
BRF Oldie
Posts: 9362
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Amber G. »

ramana wrote:What food items does India import from Japan?
Don't know but an ordinary banana sold in India (or US ), is radioactive (primarily due to K-40). IIRC (from an exercise I once gave to my nuclear physics class) radiation exposure for a typical human in US (or India) due to all the nuclear power plants, (in a year) is less than the amount of radiation dose one gets by eating one banana per year. ..
(edited later: cleaned up for clarity)

Of course - for cancer risk , 1cigarette = about 2000 bananas :)

For perspective, after Three mile island accident, local milk (with Iodine) tested was about 1/75 Bed (banana equivalent dose) per glass (IOW eating 75 bananas would give you same amount of radiation as 1 glass of tainted locall milk).. Chernobyl was bad, even mushrooms grown in Europe had 2000 bed/Kg (of radioactive Cs).. (Wine made around 1986(:) still contain higher level of radioactive isotopes because of grapes grown around those years)

Just to wanted to put the silliness in that newspaper story in perspective.
(Just in case you want to know 1 bed = about .01 mrem )

Added later: for those who want a reference, just look for 'banana equivalent dose' eg:
http://enochthered.wordpress.com/category/banana-dose/
(This gives 1 bed = .005 mrem -- depends on size i am sure..)
or http://www.ehs.unr.edu/Documents/RadSafety.pdf
(This has my value of .01 mrem) :)
Last edited by Amber G. on 16 Mar 2011 01:48, edited 2 times in total.
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

We should call the bed as AmberG number of radiation exposure!
Amber G.
BRF Oldie
Posts: 9362
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Amber G. »

^^^ bed is actually fairly commonly used (at least among some physicists and student population in MIT etc..) :) along with units like "smoot" for length etc. (even google calculator has some of these units)
astal
BRFite
Posts: 185
Joined: 07 Jul 2005 03:06
Location: virtual back bench

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by astal »

AmberG,

Thank you for the continuous flow of information.

(Edited rest of this post is superfluous)
Last edited by astal on 16 Mar 2011 02:34, edited 1 time in total.
Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Bade »

Nice posts here and a new thread !

AmberG, I was quoting news reports (NHK) when they mentioned 400 milli Sv (mSv), and assumed it was as measured within an hour or so of the event. Wiki has nice compilation.
# Cosmic radiation (from sky) at sea level = 0.24 mSv/year[1]
# Terrestrial radiation (from ground) = 0.28 mSv/year[1]
#Typical individual's natural background radiation: 2 mSv/year; 1.5 mSv/year for Australians, 3 mSv/year for Americans[3]
# Background radiation in parts of Iran, India and Europe: 50 mSv/year[3]
# Lowest clearly carcinogenic level: 100 mSv/year[3]
# Criterion for relocation after Chernobyl disaster: 350 mSv/lifetime[3]
# Highest recorded radiation outside Fukushima I Nuclear Power Plant: 400 mSv per hour.
http://en.wikipedia.org/wiki/Sievert

Why is the background rates high over Asia/Europe ?
astal
BRFite
Posts: 185
Joined: 07 Jul 2005 03:06
Location: virtual back bench

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by astal »

As the situation continues to unfold, I think this will be upgraded from a level 4 to a level 5 or 6 in terms of radiation exposure and level of catastrophe.

To the physicists again, I would like to speculate on the worst case scenarios.

1) Absolute worst case - Complete meltdown of one or more cores leading to the fissile material inside the cores reaching critical mass and the reactor(s) exploding violently releasing radiation for hundreds of miles. (Similar to Chernobyl)

(I believe that this scenario is highly unlikely due to the use of boron and other neutron killers, but is it possible?). Is this scenario what the Kamikaze solution tries to forestall?

2) More likely - Multiple cooling failures due to destruction of pipes and other components during the earthquake. This has lead to overheating and melting of the cores. But fissile materials do not attain critical mass so no chain reaction is possible.

Consequence - Radioactive materials (iodine and Cesium and even Uranium) are released by coolant in contact with the molten cores and intermittent explosions of hydrogen and other fires. The plant will have large amounts of radioactivity. It will need a long and arduous cleanup process. The area in the 20-30 km radius will need to be monitored continually for contamination.
Amber G.
BRF Oldie
Posts: 9362
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Amber G. »

Astal - Thanks, you are correct . (I edited/corrected the post for clarity).
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

Bade I was told that atmospheric testing in the 50s-thru 60s led to the absorbtion of radiation in iron ore and its very difficult to get rad-free steel for this reason for critical applications. Don't know if its urban myth.
SwamyG
BRF Oldie
Posts: 16268
Joined: 11 Apr 2007 09:22

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by SwamyG »

The paradox of nuclear power: A water-guzzling technology, yet very vulnerable to water - Brahma Chellaney

First paragraph
The troubles of the Fukushima nuclear-power plant — and other reactors — in northeast Japan have dealt a severe blow to the global nuclear industry, a powerful cartel of less than a dozen major state-owned or state-guided firms that have been trumpeting a nuclear-power renaissance.
Last paragraph
Fukushima is likely to stunt the appeal of nuclear power in a way similar to the accident at the Three Mile Island plant in Pennsylvania in 1979, not to mention the far more severe meltdown of the Chernobyl reactor in 1986. If the fallout from those incidents is a reliable guide, however, nuclear power’s advocates will eventually be back.
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

I agree there will be cap for sometime. Good till atleast MMS sees reason and can stall US pressure to buy their wares.

8)
Prasad
BRF Oldie
Posts: 7794
Joined: 16 Nov 2007 00:53
Location: Chennai

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Prasad »

ramana wrote:Bade I was told that atmospheric testing in the 50s-thru 60s led to the absorbtion of radiation in iron ore and its very difficult to get rad-free steel for this reason for critical applications. Don't know if its urban myth.
Perhaps it is more due to the thorium deposits in Kerala that push the average up for India and other similar countries.
A_Gupta
BRF Oldie
Posts: 12265
Joined: 23 Oct 2001 11:31
Contact:

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by A_Gupta »

http://www.nytimes.com/2011/03/16/world ... ar.html?hp
At least 750 workers were evacuated on Tuesday morning after a separate explosion ruptured the inner containment building at Reactor No. 2 at the Daiichi plant, which was crippled by Friday’s earthquake and tsunami. The explosion released a surge of radiation 800 times more intense than the recommended hourly exposure limit in Japan.

But 50 workers stayed behind, a crew no larger than would be stationed at the plant on a quiet spring day. Taking shelter when possible in the reactor’s control room, which is heavily shielded from radiation, they struggled through the morning and afternoon to keep hundreds of gallons of seawater a minute flowing through temporary fire pumps into the three stricken reactors, Nos. 1, 2 and 3, where overheated fuel rods continued to boil away the water at a brisk pace.
vijayk
BRF Oldie
Posts: 8932
Joined: 22 Jun 1999 11:31

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by vijayk »

As per my understanding, the catastrophe happened because:

1. The earthquake knocked out the electricity.
2. The tsunami destroyed the backup generators of the plant.
3. There is no power to cool the hot steam which is caused the temperature to raise causing explosion of hydrogen.

Could this have been avoided if they had another backup option of cooling the steam such as geothermal cooling as my middle school old son pointed out?
Amber G.
BRF Oldie
Posts: 9362
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Amber G. »

Astal - Many of your question may have answer in the MIT site which Mort W gave the link before:
http://mitnse.com/
(Go to the original post by Josef Oehmen some where at the end. .it describes Fundamentals of nuclear reactions..
and ...
It is worth mentioning at this point that the nuclear fuel in a reactor can never cause a nuclear explosion like a nuclear bomb. At Chernobyl, the explosion was caused by excessive pressure buildup, hydrogen explosion and rupture of all structures, propelling molten core material into the environment....
Basically:
1) Absolute worst case - Complete meltdown of one or more cores leading to the fissile material inside the cores reaching critical mass and the reactor(s) exploding violently releasing radiation for hundreds of miles. (Similar to Chernobyl)
'Atomic explosion' is not going to happen - even if no control rods fell and all the water evaporated (even with weapons grade material, it is not easy to make a bomb )..water gone (no moderator) ==> fission will stop. The worse case here is "dirty bomb" (with conventional explosion) rather than "atomic bomb", of course, pretty bad, with lot of radioactivity and what not but still order of magnitude less than an atomic bomb. (for perspective about 50 fire fighters died right away in Chernobyl while in Hiroshima immediate toll was in hundreds of thousands)

Meltdown scenario /radio activity spread is quite serious ...9.0 earthquake is quite serious.
Last edited by Amber G. on 16 Mar 2011 03:18, edited 1 time in total.
A_Gupta
BRF Oldie
Posts: 12265
Joined: 23 Oct 2001 11:31
Contact:

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by A_Gupta »

http://www.nytimes.com/2011/03/16/world ... ntain.html
The warnings were stark and issued repeatedly as far back as 1972: If the cooling systems ever failed at a Mark 1 nuclear reactor, the primary containment vessel surrounding the reactor would probably burst as the fuel rods inside overheated. Dangerous radiation would spew into the environment.
...
...
In some reactors, known as pressurized water reactors, the system is sealed inside a thick, steel-and-cement tomb. Most nuclear reactors around the world are of this type.

But the type of containment vessel and pressure suppression system used in the failing reactors at Japan’s Fukushima Daiichi plant — and in 23 American reactors at 16 plants — is physically less robust, and it has long been thought to be more susceptible to failure in an emergency than competing designs.

G.E. began making the Mark 1 boiling water reactors in the 1960s, marketing them as cheaper and easier to build — in part because they used a comparatively smaller and less expensive containment structure.

American regulators began identifying weaknesses very early on.

...
...
A written response came later that same year from Joseph Hendrie, who would later become chairman of the N.R.C. He called the idea of a ban on such systems “attractive” because alternative containment systems have the “notable advantage of brute simplicity in dealing with a primary blowdown.”

But he added that the technology had been so widely accepted by the industry and regulatory officials that “reversal of this hallowed policy, particularly at this time, could well be the end of nuclear power.”

In an e-mail on Tuesday, David Lochbaum, director of the Nuclear Safety Program at the Union for Concerned Scientists, said those words seemed ironic now, given the potential global ripples on the nuclear industry from the Japanese accident.

“Not banning them might be the end of nuclear power,” said Mr. Lochbaum, a nuclear engineer who spent 17 years working in nuclear facilities, including three that used the G.E. design.

Questions about the G.E. reactor design escalated in the mid-1980s, when Harold Denton, an official with the N.R.C., asserted that Mark 1 reactors had a 90 percent probability of bursting should the fuel rods overheat and melt in an accident. A follow-up report from a study group convened by the commission concluded that “Mark 1 failure within the first few hours following core melt would appear rather likely.”

In an extreme accident, that analysis held, the containment could fail in as little as 40 minutes.

Industry officials disputed that assessment, saying the chance of failure was only about 10 percent.
ramana
Forum Moderator
Posts: 59854
Joined: 01 Jan 1970 05:30

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by ramana »

Vijayk,
They have powered cooling thru electric pumps with back-up electricity from :Diesel generators(tsunamied out) and batteries (limited life: 8hrs or so). They also have emergency pressurized tanks which dump coolant water (one shot deal). The problem is not cooling hot steam but the reactor core which has decay heat. When the water hits the exposed hot (thermal) reactor core it dissassociates into hydrogen and oxygen. The explosion is from the hydrogen accumulation.
A_Gupta
BRF Oldie
Posts: 12265
Joined: 23 Oct 2001 11:31
Contact:

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by A_Gupta »

http://www.nytimes.com/2011/03/16/world ... 6fuel.html
Even as workers race to prevent the radioactive cores of the damaged nuclear reactors in Japan from melting down, concerns are growing that nearby pools holding spent fuel rods could pose an even greater danger.
....
....
If any of the spent fuel rods in the pools do indeed catch fire, nuclear experts say, the high heat would loft the radiation in clouds that would spread the radioactivity.

“It’s worse than a meltdown,” said David A. Lochbaum, a nuclear engineer at the Union of Concerned Scientists who worked as an instructor on the kinds of General Electric reactors used in Japan. “The reactor is inside thick walls, and the spent fuel of Reactors 1 and 3 is out in the open.”
...
A 1997 study by the Brookhaven National Laboratory on Long Island described a worst-case disaster from uncovered spent fuel in a reactor cooling pool. It estimated 100 quick deaths would occur within a range of 500 miles and 138,000 eventual deaths.

The study also found that land over 2,170 miles would be contaminated and damages would hit $546 billion.

That section of the Brookhaven study focused on boiling water reactors — the kind at the heart of the Japanese crisis.
Amber G.
BRF Oldie
Posts: 9362
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Amber G. »

^^^ has been posted before that fire in unit 4, as well as high temp in pool for unit 5 and 6.
suryag
Forum Moderator
Posts: 4045
Joined: 11 Jan 2009 00:14

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by suryag »

Koodankulam better?
Koodankulam reactors quite safe

Btw lots of rescued people shown on tv are old people(> 60 years) were the earthquake hit areas retired people friendly cities like our erstwhile bengaluru?
Theo_Fidel

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Theo_Fidel »

FWIW the BWR was promoted as a 'cheap' option compared to the heavy concrete and steel tomb construction at that time.

I wonder if the lack of a cooling tower caused a part of this crisis. With a cooling tower they would have a lot of pumping capacity and a lot of water available. I still can't believe that they couldn't run a small navy ship into the harbor as a temporary power source. Many of those ships have 20-40 MW power plants that generate electricity.
suryag
Forum Moderator
Posts: 4045
Joined: 11 Jan 2009 00:14

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by suryag »

folks what is this thing about harm from spent fuel rods, what is the rationale behind saving it at the reactor. Why would anyone keep these over there. Only 50 people working on safeguarding the reactor :( Unkil should do something this is after all their design
Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Bade »

Though it is being widely assumed that quake itself did not do damage of any kind, it remains to be seen if that assumption is really true at least for this plant site.

The recurring problems in reactor units which were shutdown months ago, means some structural damage/cracks did happen and led to coolant leakages. Even spent fuel rod pools have difficulty and transient fires.

Electrical systems probably underwent water damage too from the Tsunami flooding, but how can one absolutely rule out damage from a 9.0 quake even if the epicenter is far away and structures were only rated for < 8.0 shaking.
Amber G.
BRF Oldie
Posts: 9362
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Amber G. »

Fact Sheet ( Fuel Storage at the Fukushima Daiichi Nuclear Power Plant) and updates
Key Facts
 Used nuclear fuel at the Fukushima Daiichi plant is stored in seven pools and in a dry container storage facility (containing nine casks).
 Sixty percent of the used fuel on site is stored in the shared pool, in a building separated from the reactor buildings; 34 percent of the used fuel is distributed between the six reactor fuel storage pools, and the remaining six percent is stored in the nine dry storage containers. There are no safety concerns regarding the used fuel in dry storage at Fukushima Daiichi.
<snip>
What Could Happen During an Accident?
 The systems that cool and maintain water levels in the pools are designed to withstand severe events. If these systems are unable to function, the heat generated by the used fuel would result in a slow
increase in the temperature of the spent fuel pool water. The operating temperature of the pools is typically around 40 degrees C or 100 degrees F (the boiling point for water is 100 C or 212 F). This slow increase in temperature would result in an increased evaporation rate. Rapid evaporation of the water will not occur.
 Exact evaporation rates would depend on the amount of used fuel in the pool and how long it has cooled. The rate at which the pool water level would decrease (due to evaporation or mild boiling) in the absence of cooling system function would not be expected to lower water levels by more than a few percent per day. Given that there is approximately 16 feet or more of water above the used fuel assemblies, operators would have ample time (days to weeks) to find another way to add water to the
pools before the fuel would become exposed. For example, water could easily be added using a fire hose.2
<snip> .
Also website says:
Tokyo Electric Power Co. said that an oil leak in a cooling water pump at Unit 4 was the cause of a fire that burned for approximately 140 minutes. The fire was not in the spent fuel pool, as reported by several media outlets. Unit 4 was in a 105-day-long maintenance outage at the time of the earthquake and there is no fuel in the reactor.
Also:

The U.S. Nuclear Regulatory Commission has sent 11 experts to Tokyo to provide assistance requested by the Japanese government. Two reactor experts were dispatched Saturday; others began departing Monday.
Suppiah
BRF Oldie
Posts: 2569
Joined: 03 Oct 2002 11:31
Location: -
Contact:

Re: 2011 Japanese Earthquake and Tsunami - News and Analysis

Post by Suppiah »

Purush wrote:Let us not score self-goals for no reason. There are many things wrong with the Indian system, but we can appreciate/observe the japanese relief efforts without denigrating our own people at this time.
Despite the presence of honorary packees in our midst, India also has lots of brave/selfless people who will put themselves in harms way for their fellow citizens, regardless of political affiliation.
Purush, it is a self goal yes but not without reason. I agree with you that there are brave/selfless but these are mostly in the lowest of the low economic and social class. The upper and middle classes are full of selfish and ruthless and that pretty much explains our current situation. On numerous occasions port, bank, BSNL, airline and other unions have called for strikes at critical situations for the economy / country and policemen have run away in Mumbai instead of confronting the terrorists (and elsewhere). On the contrary the safai workers of Mysore (to give just one example) canceled their agitation for the sake of Dasara as foreigners visit the city in large numbers though they were not paid at all...

OT sorry abt that..
Locked