Butrflynet
 
  0  
Reply Thu 17 Mar, 2011 06:51 pm
@Butrflynet,
IAEA has issued a correction to their earlier statement. The text in red has been eliminated and been replaced in the original announcement.

Japanese Earthquake Update (17 March 16:55 UTC) — CLARIFIED

17 March 2011

Announcements, Featured

Japanese authorities have informed the IAEA that engineers were able have begun to lay an external grid power line cable to unit 2. The operation was completed at 08:30 UTC. The operation was continuing as of 20:30 UTC, Tokyo Electric Power Company officials told the Nuclear and Industrial Safety Agency.

They plan to reconnect power to unit 2 once the spraying of water on the unit 3 reactor building is completed.

The spraying of water on the unit 3 reactor building was temporarily stopped at 11:09 UTC (20:09 local time) of 17 March.

The IAEA continues to liaise with the Japanese authorities and is monitoring the situation as it evolves.
farmerman
 
  0  
Reply Thu 17 Mar, 2011 07:00 pm
@Butrflynet,
not to be a noodge but I saw a small harmonic seismic report from one of the US "supercalderas", but I forgot which one.
Theres Yellowstone (Snake River hotspot), Isalnd park Idaho:La Garita Colo; long Valley Calif; Valles (jemez NM) These are the onl supervolcano calderas we have in Continental US
roger
 
  1  
Reply Thu 17 Mar, 2011 07:15 pm
@farmerman,
Thanks loads.
ossobuco
 
  1  
Reply Thu 17 Mar, 2011 07:28 pm
@roger,
Great, I just got used to not sticking anything on a non cabinet shelf with some kind of gum ball stuff.
oralloy
 
  1  
Reply Thu 17 Mar, 2011 07:32 pm
@georgeob1,
georgeob1 wrote:
Information is understandably spotty and inconsistent. Apparently the containment structures for all three reactors have held, but the containment for a spend fuel storage area was breeched in an explosion of evolved hydrogen gas.


My understanding is that the spent fuel rods have no real containment to begin with -- all there was was a pool to keep them from overheating.
roger
 
  1  
Reply Thu 17 Mar, 2011 07:33 pm
@ossobuco,
Think we're far enough from Yellowstone that chewing gum would help?
oralloy
 
  1  
Reply Thu 17 Mar, 2011 07:39 pm
Smoke or steam at crippled Japan reactor could be explosion

Thu Mar 17, 2011 9:04pm EDT

TOKYO (Reuters) - Smoke or steam rising from the crippled No.2 reactor in northeastern Japan could be coming from the spent fuel pool or from an explosion in the suppression chamber, the nuclear safety agency said on Friday.

http://www.reuters.com/article/2011/03/18/japan-smoke-idUSWNAS141720110318
0 Replies
 
oralloy
 
  1  
Reply Thu 17 Mar, 2011 08:01 pm
@Butrflynet,
Butrflynet wrote:
IAEA has issued a correction to their earlier statement. The text in red has been eliminated and been replaced in the original announcement.

Japanese Earthquake Update (17 March 16:55 UTC) — CLARIFIED

17 March 2011

Announcements, Featured

Japanese authorities have informed the IAEA that engineers were able have begun to lay an external grid power line cable to unit 2. The operation was completed at 08:30 UTC. The operation was continuing as of 20:30 UTC, Tokyo Electric Power Company officials told the Nuclear and Industrial Safety Agency.

They plan to reconnect power to unit 2 once the spraying of water on the unit 3 reactor building is completed.

The spraying of water on the unit 3 reactor building was temporarily stopped at 11:09 UTC (20:09 local time) of 17 March.

The IAEA continues to liaise with the Japanese authorities and is monitoring the situation as it evolves.


Assuming they get power to the pumps and resume cooling, how long is their cooling system going to last with all that seawater now in it?
0 Replies
 
ossobuco
 
  1  
Reply Thu 17 Mar, 2011 08:54 pm
@roger,
I've just equilibrated to that (was thinking re Jemez).

Not that I am quaking.

Hard to rattle me.
Butrflynet
 
  1  
Reply Thu 17 Mar, 2011 09:43 pm
@farmerman,
Speaking of harmonics, scroll down to the end of this article (or read it) and watch the video. Someone has put the seismic signature of the earthquake to sound.

http://www.pbs.org/wnet/need-to-know/the-daily-need/a-chilling-aural-portrait-of-the-deadly-earthquake-near-japan/7906/
0 Replies
 
roger
 
  1  
Reply Thu 17 Mar, 2011 10:57 pm
@ossobuco,
Is Jemez the same as the Valles Caldera? That one is safe. I know it is because they are raising cattle on the floor of it.
farmerman
 
  1  
Reply Fri 18 Mar, 2011 12:05 am
@roger,
Yep, Valles has erupted about 1.2 million years ago but its not extinct. Of course Id be more concerned about theYellowstone, Island Park, and Garita calderas.

ossobuco
 
  1  
Reply Fri 18 Mar, 2011 12:07 am
@farmerman,
I think I'll skip it.
0 Replies
 
Ionus
 
  1  
Reply Fri 18 Mar, 2011 12:40 am
@dyslexia,
Quote:
this is the worst nuclear accident since Chernobyl in recorded history
Perhaps it means they have others that they didnt record ?? Paperwork...who needs it .
0 Replies
 
High Seas
 
  0  
Reply Fri 18 Mar, 2011 09:05 am
@farmerman,
farmerman wrote:

Quote:
Most of the dispersed radiation is from gases that have short half lives: once the leaks are contained it will dissipate quickly.
Naaah, I dont consider Cesium 137 as a "short lived nuclide". And its volatile besides. Ive seen reports of Cs in the atmosphere and that tells us that at least some of the Zr cladding has been compromised

Your post was addressed to someone who knows exactly what it means, but there are many posters here who actually worry about potential radioactive fallout (cesium, iodine, etc) beyond Fukushima Daiichi, first, and, second, don't know cesium from zirconium, so here's a quick update for them:

1. Quit worrying! This low-level radioactivity may keep seeping out of that plant's reactors and spent fuel pools for weeks to come but it poses no danger to anyone beyond the current safe perimeter. Helicopter pilots dropping water on the plant - obviously passes last less than 1 hr since water tanks must be refilled with 7+ tons of seawater, pilots wear protective suits, helicopter provides shielding - receive radiation equivalent of 10 chest X-rays/hr.
2. Source for above is US-supplied drone and U-2 plane which have been taking detailed radiation readings over the plant at various altitudes.
3. Anybody in North America or Eurasia still worried - please ignore the clueless idiot we got as "US surgeon general" who advised residents to swallow potassium iodide tablets. If you now reside near sea level, and you move to a house located 1,000 ft uphill, you'll get more radiation than can ever be generated by Daiichi - even if this ongoing mess continues for weeks to come, as seems likely. The plant has to be cleaned up before getting buried in boron-loaded concrete, btw, because otherwise radioactivity will poison Japanese ground waters and unknowable volumes of Pacific ocean waters.
4. Anybody in the southern hemisphere, keep in mind the jet stream cannot cross the equator: here is today's jet stream map - centered on North pole:
http://squall.sfsu.edu/gif/jetstream_norhem_00.gif
5. Cesium exists in the atmosphere as a leftover from nuclear tests in both north and south hemispheres. Everyone born after 1949 already has some.
Butrflynet
 
  1  
Reply Fri 18 Mar, 2011 10:32 am
Weather patterns are changing today, according to CNN. There is a high offshore that will have the winds coming from the southeast and blowing over the city of Sendai, a city of a million people.
0 Replies
 
Butrflynet
 
  1  
Reply Fri 18 Mar, 2011 10:36 am
Updates from NHK:

Outside power source won't be available soon


The government says an outside power source is unlikely to be available at the Fukushima Daiichi nuclear plant for some time, although electricity is urgently needed to cool the reactors.

The Nuclear and Industrial Safety Agency said on Friday that the installation of power cables at the Number One and Number 2 reactors is expected to be completed on Saturday. The operation to add power cables at the Number 3 and Number 4 reactors is likely to end on Sunday.

The agency said, however, that it will take some time to confirm the safety of the damaged facilities.

The government and Tokyo Electric Power Company have been scrambling to restore power at the plant to restart the cooling systems for the reactors.

The earthquake and tsunami on March 11th severed the plant's electricity supply and destroyed its emergency generators.

Friday, March 18, 2011 21:24 +0900 (JST)


Fukushima nuclear reactor doused for 2nd day

Japan's Self-Defense Force units have for the 2nd day shot water at one of the reactors at the disaster-stricken Fukushima Daiichi nuclear power plant. Work to restore power to the compound is also underway.

On Friday afternoon, SDF units used special fire engines to discharge tons of water at the plant's No.3 reactor.
A storage pool for spent nuclear fuel rods has lost its cooling function, raising the risk of a massive radioactive leak.

Water was also discharged by the Tokyo Electric Power Company, or TEPCO, which runs the plant.

TEPCO's office in Fukushima says that following the cooling attempts, radiation levels fell slightly 500 meters northwest of the No. 3 reactor.
It says post-operation readings taken as of 2:50 PM stood at 3,339 microsieverts per hour, compared to 3,484 microsieverts at 1:50 PM, before the work began.

TEPCO cautioned that the decline is small and a close analysis is needed before any judgment can be made about the effects of the operation.

This is the 2nd straight day that SDF units have released water at the No.3 reactor. The operation on the previous day took place from the air and ground.

On Friday, work to restore electricity at the Daiichi plant also went into full swing. Securing an external power source could allow the reactors to regain their cooling functions, which are considered vital to put them under control.

Friday, March 18, 2011 21:24 +0900 (JST)



Expert: No immediate risk but figure is high

Associate Professor Keiichi Nakagawa of the University of Tokyo has suggested that 150 microsieverts per hour would not pose an immediate danger to humans, but the figure is still high.

The specialist in radiology says exposure to 150 microsieverts of radiation every day for up to a month would add up to around 100,000 microsieverts. He says human health could be affected at this level.

However, Nakagawa says people should not worry too much, since the amount of radiation would fall to about 10 percent indoors.

But he adds that the release of radioactive substances from the nuclear plant should be contained as soon as possible, from the viewpoint of preventing unnecessary long-term exposure.

Friday, March 18, 2011 22:02 +0900 (JST)
0 Replies
 
georgeob1
 
  1  
Reply Fri 18 Mar, 2011 10:39 am
@oralloy,
oralloy wrote:

georgeob1 wrote:
Information is understandably spotty and inconsistent. Apparently the containment structures for all three reactors have held, but the containment for a spend fuel storage area was breeched in an explosion of evolved hydrogen gas.


My understanding is that the spent fuel rods have no real containment to begin with -- all there was was a pool to keep them from overheating.


The pool was enclosed in a reinforced concrete structure. I don't know the design details, however, given the predictable possibility of the evolution of free hydrogen from the meltdown of the zirconium cladding in the event of the loss of coolant, the facility should have either been open to the atmosphere (to prevent the accumulation of an explosive concentration of hydrogen) or enclosed in a structure that could withstand such an explosion. Enclosing it in a weak structure (if that indeed is the case) would not be a wise option.

High Seas' statements above about the likely radiation levels and their real effects are accurate.
cicerone imposter
 
  1  
Reply Fri 18 Mar, 2011 11:30 am
@georgeob1,
I would think that the enclosure for the spent fuel was structurally sound for earthquakes. Without the experience of the recent tsunami with 30 feet waves, hindsight is 20/20.
High Seas
 
  4  
Reply Fri 18 Mar, 2011 12:05 pm
@cicerone imposter,
The spent fuel pools (red circle on reactor design) weren't damaged by the earthquake. Damage came later, when cooling failed and they overheated:
http://bravenewclimate.files.wordpress.com/2011/03/gereactor_snfpond.jpg?w=374&h=406

http://resources.nei.org/documents/japan/Used_Fuel_Pools_Key_Facts_March_16_Update.pdf
Quote:
The used fuel pools are designed so that the water in the pool cannot drain down as a result of damage to the piping or cooling systems. The pools do not have drains in the sides or the floor of the pool structure. The only way to rapidly drain down the pool is to have structural damage of the walls or the floor. As of mid-day March 15, there is no evidence to date that this has occurred.
0 Replies
 
 

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