Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[83729780]

Don't know if that was posted here before:

http://www.mod.go.jp/j/approach/defense/saigai/tohokuoki/temp.html

Daily thermal images from the reactors.

why the hot spots in the turbine bldgs?

 

[timeasterday]

I would like to know it too.

The generators Exelon is using in the United States are :



And locomotives are air-cooled, aren't they ?

Yes, they are radiator cooled. They mention "locomotive-sized" which I take it to mean very big. The larger generators we make (>3MW) typically use remote-mounted radiators unless they are CHP applications.

 

[WhoWee]

A pipe was not in my thoughts.
But if the whole island moved about eight feet or more, a pipe would be fine.

Perhaps, with so many variables it is hard to predict. IMO - the only certain system would be something powered by the reactor heat in the event of electrical failure.

 

[AntonL]

Tsunami Warnings/Advisories

http://www.jma.go.jp/en/tsunami/


A strong earthquake with a preliminary magnitude of 7.1 shook buildings in Tokyo and a wide swathe of eastern Japan on Monday, with an advisory for a one-meter tsunami issued after the quake. reuters

It is now downgraded to 6.6 but most interesting it triggered a swarm of nine aftershocks within two hours, a 5.2 only ten minutes later followed four minutes later by a 4.7

Whereas, the 7.1 quake on 7 April had two 4.6 aftershocks about an hour later and the third 7.5 hours later

http://earthquake.usgs.gov/earthquakes/recenteqsww/Maps/10/140_35_eqs.php

Follow Up: the swarm of aftershocks continues 22 aftershocks in 8 hours !
compare this to 67-22 = 45 for the week preceding todays 6.6 event
something is rumbling beneath the Earth - any seismologist here?

For the last week I binned the number of aftershocks into 6 hour periods or quarter days
Zero being today's 6.6 event, below is the graph,
in the little map red=last hour, blue=last 24 hours, yellow=last week

Status Mon Apr 11 18:11 UTC 2011
[PLAIN]http://k.min.us/iknF6a.JPG

 

[ivars]

Follow Up: the swarm of aftershocks continues 22 aftershocks in 8 hours !
compare this to 67-22 = 45 for the week preceding todays 6.6 event
something is rumbling beneath the Earth - any seismologist here?

There is a bigger aftershock still due. This 6.6. was pretrigerred, got of too early, hence it was small, hence so much energy still unsettled ( many aftershocks) . Since it got triggered before its time, the bigger energy it was supposed to release is still in the fault.

I expect one more aftershock >7, perhaps >7.5 very soon - 1-2 week time. May be some >M6 foreshock swarming ( 3-5) before that.

Almost every huge (>9.0) quake had one late (up till 3 months ) huge aftershock. At least Sumatra had.

I am not a seismologist, God forbid. For seismologist, EQ are unpredictable. I predicted both 7.1 and 6.6 aftershock both time and magnitude wise, and expect one more , the biggest, to come. Without any probability, just happen.

 

[shogun338]

Here is a pdf to the report showing the radiation in the environment years later from the 1986
Edwin I. Hatch Nuclear Plant Accident in Georgia USA where water from the spent fuel pool was released outside into a swamp on the plant property . If you look at the plant on Google Earth you can see the small creek that flows from this swamp into the Altamaha river which is right next to the plant . I fish this area often in the summer months and never knew this was the location the swamp drained into until I found it recently on the internet . The Japanese people will be dealing with much worse in the decades to come .
Assessment of Results of Augmented Radiological

Environmental Monitoring Program for the Years 2000 through 2007 http://www.nrc.gov/info-finder/reactor/hat2.html

 

[ivars]

Radiation Up To 4 Times Higher Than Chernobyl Evac Zone Found In Soil 30 km Away From Fukushima; Rice Harvest In Question

Now a new study from Hiroshima and Kyoto Universities has found that the radioactive content of soil samples beyond the 30 km semi-evacuation zone is as much as 400 times the normal. From Asahi: "The predicted changes in the level of radiation at the ground surface were calculated after analyzing the amounts of eight kinds of radioactive materials found in the soil and taking into consideration the half-lives of each material. The study results are considered more accurate than the study conducted by the science ministry, which only released information concerning two types of radioactive material. [Scholars] collected soil samples from five locations in the village at depths of five centimeters. All the locations were outside the 30-km radius and were by roadways in various hamlets. The study found cesium-137 at levels between about 590,000 and 2.19 million becquerels per cubic meter." Comparing this to Chernobyl: "After the Chernobyl nuclear accident in the former Soviet Union in 1986, residents who lived in areas where cesium-137 levels exceeded 555,000 becquerels were forced to move elsewhere. The amounts of cesium-137 found in Iitate were at most four times the figure from Chernobyl."

http://www.asahi.com/english/TKY201104080169.html

 

[gmax137]

Yes, they are radiator cooled. They mention "locomotive-sized" which I take it to mean very big. The larger generators we make (>3MW) typically use remote-mounted radiators unless they are CHP applications.

I have seen radiator cooled emergency diesels at some plants and water cooled EDGs at other plants. The EDGs are typically 10 or 12 cylinder locomotive engines; their capacity is in the 1.5 to 2.5 MW range.

 

[timeasterday]

No, they could have used that water for emergency cooling of the reactors AFTER the damage instead of sea water. Sorru... hadn't followed the previous threads very comprehensively!
Some images just released... mostly terrible resolution!
http://cryptome.org/eyeball/daiichi-npp6/daiichi-photos6.htm

Honeywell should be embarrassed by those photos! Is that what our military has been spending money on?

 

[gmax137]

...when millions of lives are at stake ...

Where did you get that idea?

 

[james14]

I realize this is speculation on my part, but all of these latest statements including the one about 10,000 TBq per hour for a number of hours really seems to point to them knowing quite a bit more than they are letting on.

 

[|Fred]

Considering that at d + almost 30 , they aren't any closer to restore cooling , if anything situation is worse , containment is not really containing , what option do they have ? They can't let it bleed out for ever ...

 

[gmax137]

This sounds close enough to the "D/G Inoperable due to Tsunami flood" analysis on page 12 of http://www.nisa.meti.go.jp/english/f...110406-1-1.pdf and professor Yoshiaki Oka's analysis :

Emergency DGs started at the earthquake. But Tsunami damaged ultimate heat sinks (sea water pumping and cooling system) of units 1F1-4. caused common cause failure

If the intake structure was damaged enough to compromise the service water system (whatever its name is in a BWR), then none of the cooling systems would be available, right? Regardless of whether the diesels were running or not? I don't have a clear idea of the BWR systems, and how the steam-driven (RCIC?) is supposed to work in the long term. Can you maintain cooling that way (steam driven pumps) in the long-term, or do you necessarily need to cool the water in the torus, removing the heat via the service water system? Does anyone have a link to a good description of these systems?

 

[tsutsuji]

Radiation Up To 4 Times Higher Than Chernobyl Evac Zone Found In Soil 30 km Away From Fukushima; Rice Harvest In Question



http://www.asahi.com/english/TKY201104080169.html

The report is probably the following one : http://www.rri.kyoto-u.ac.jp/NSRG/seminar/No110/iitatereport11-4-4.pdf

http://www.rri.kyoto-u.ac.jp/NSRG (Nuclear Safety Research Group at Research Reactor Institute, Kyoto University) provides a link to http://hamanora.blog.ocn.ne.jp/kaiin02/ where there is more to read.

 

[TCups]

Considering that at d + almost 30 , they aren't any closer to restore cooling , if anything situation is worse , containment is not really containing , what option do they have ? They can't let it bleed out for ever ...

An interesting question, indeed. Posited another way: If the emergency efforts to cool the reactor cores are (and it would seem, can only be) a temporary solution as long as the coolant (water) is not contained in a closed system,

Then only three alternatives exist:

1) Continue to spill contaminated water and slowly (relatively) contaminate the ground water and ocean while temporizing. (possibly, to allow time to deal with the spent fuel in the SFPs?), or

2) Somehow devise a stable, permanent system to contain, decontaminate and if possible, recirculate the water being used for cooling the cores (unlikely), or

3) Prepare to let the cores melt and deal with the consequences.

Is there another option I am missing? If not, then option (3), it seems, is most likely the "not if, but when" final event in the Fukushima disaster sequence.

Which begs the question: What might be done while temporizing with the current efforts to cool the cores to mitigate the ultimate consequences of one or more melted reactor cores with loss of the primary containment? If the answer to that question is "nothing effective", then, is option (1) with ongoing contamination by un-contained, highly contaminated water for as long as humanly possible worse than option (3)?

I don't know.

 

[bytepirate]

Here is another good overview of the Fukushima event.
www.vgb.org/vgbmultimedia/News/Fukushimav15VGB.pdf

a good overview, but:
"Recriticality in Unit 2 ?
(according to soil samples,
might explain radioactivity spike on march 16)"

is there *any* evidence for a recriticality in #2?
the spike on march 16th could be much better explained by (undetected??) melting/burning fuel in #4 SFP (imho):
there was an explosion before:
http://www.tepco.co.jp/en/press/corp-com/release/11031504-e.html
and a fire afterwards:
http://www.tepco.co.jp/en/press/corp-com/release/11031606-e.html
and in the meantime, the (then uncooled) fuel took a nap?

 

[AntonL]

3) Prepare to let the cores melt and deal with the consequences.

a core melt might be a cleaner solution than a continues feed and bleed, only if it can be guaranteed that the molten core does not go critical, and to prevent a steam explosion the dry well must dry which it is not.

 

[biscuitcheese]

An interesting question, indeed. Posited another way: If the emergency efforts to cool the reactor cores are (and it would seem, can only be) a temporary solution as long as the coolant (water) is not contained in a closed system,

Then only three alternatives exist:

1) Continue to spill contaminated water and slowly (relatively) contaminate the ground water and ocean while temporizing. (possibly, to allow time to deal with the spent fuel in the SFPs?), or

2) Somehow devise a stable, permanent system to contain, decontaminate and if possible, recirculate the water being used for cooling the cores (unlikely), or

3) Prepare to let the cores melt and deal with the consequences.

Is there another option I am missing? If not, then option (3), it seems, is most likely the "not if, but when" final event in the Fukushima disaster sequence.

Which begs the question: What might be done while temporizing with the current efforts to cool the cores to mitigate the ultimate consequences of one or more melted reactor cores with loss of the primary containment? If the answer to that question is "nothing effective", then, is option (1) with ongoing contamination by un-contained, highly contaminated water for as long as humanly possible worse than option (3)?

I don't know.

I don't know what the sea depths are near the plant, or what kind of logistic/financial nightmare it may be, but why couldn't they hire or buy a bunch of oil tankers to sit off the coast to facilitate easier siphoning of contaminated water from the plant to the oil tankers as an expendible temporary storage solution for the contaminated water?

It seems to be better than purposely dumping what is already collected/contained radioactive water into the ocean because 'they had no choice'. If it was an uncontrollable leak that's one thing, but if their problem is with storage (and it seems to be the case earlier with the purposeful dumping), then there are obvious solutions that can be had like hiring/buying oil tankers to store the water.

 

[Pheesh]

Well it's now basically official, I guess they just felt like skipping 6!

The Japanese government's nuclear safety agency has decided to raise the crisis level of the Fukushima Daiichi power plant accident from 5 to 7, the worst on the international scale.

The Nuclear and Industrial Safety Agency made the decision on Monday. It says the damaged facilities have been releasing a massive amount of radioactive substances, which are posing a threat to human health and the environment over a wide area.

http://www3.nhk.or.jp/daily/english/12_05.html

 

[biscuitcheese]

Well it's now basically official, I guess they just felt like skipping 6!

http://www3.nhk.or.jp/daily/english/12_05.html

It baffles the mind how many so called 'experts' were on the news early in this disaster, who were adamant that the still developing situation could not possibly be worse than the TMI incident and that a disaster rating above 4 was impossible.

It seemed so obvious right from the very start the accident was worst than TMI because (1) there was reportedly a hydrogen explosion which for all intents and purposes can likely only occur if fuel rods were overheating leading to thermolysis of water catalysed with the zirc-water reaction to generate the hydrogen in the first place, and (2) the military subsequently detected I and Cs radioisotopes off the coast that obviously came from the reactor likely due to pressure releast from primary containment. Ultimately though, the facts have already demonstrated long ago that core overheating happened (likely with fuel cladding melting also since they didnt get cooling in there for a long time) and also that radioactive elements were already released into the atmosphere thus proven very early to be worse than TMI since TMI had fuel melting but no substantial amount of radioisotopes were released into the atmosphere and that there was no indications of breach in containment (not even the outer containment) for which was certainly not the case in the fukushima incident.

 

[bytepirate]

An interesting question, indeed. Posited another way: If the emergency efforts to cool the reactor cores are (and it would seem, can only be) a temporary solution as long as the coolant (water) is not contained in a closed system,

Then only three alternatives exist:

1) Continue to spill contaminated water and slowly (relatively) contaminate the ground water and ocean while temporizing. (possibly, to allow time to deal with the spent fuel in the SFPs?), or

2) Somehow devise a stable, permanent system to contain, decontaminate and if possible, recirculate the water being used for cooling the cores (unlikely), or

3) Prepare to let the cores melt and deal with the consequences.

Is there another option I am missing? If not, then option (3), it seems, is most likely the "not if, but when" final event in the Fukushima disaster sequence.

Which begs the question: What might be done while temporizing with the current efforts to cool the cores to mitigate the ultimate consequences of one or more melted reactor cores with loss of the primary containment? If the answer to that question is "nothing effective", then, is option (1) with ongoing contamination by un-contained, highly contaminated water for as long as humanly possible worse than option (3)?

I don't know.

maybe they need a feynman (or any other brilliant mind, preferred alive) to come up with an unexpected fourth solution.
something like:
fill up the RPV with copper pellets, then pour in some radiator sealant (i have heard pepper and eggs are working), then cool the thing from the outside.

this is not a serious suggestion, but maybe the final solution will be something like that: unexpected, ridiculous - and working.

 

[83729780]

Is there another option I am missing?

I honestly think they're still considering the giant cloth. It's been mentioned twice in Kyodo news reports.

 

[Borek]

Considering that at d + almost 30 , they aren't any closer to restore cooling , if anything situation is worse , containment is not really containing , what option do they have ? They can't let it bleed out for ever ...

Amount of heat evolving should be getting down, even if there are short criticalities. Once the power gets down they can stop cooling. But I doubt there is much that can be done earlier.

 

[StrangeBeauty]

Pardon if this is a repost: They've issued corrections to a number of released readings/info including pressure readings for RPVs #1 and #3:

http://www.nisa.meti.go.jp/english/files/en20110411-3.pdf

[Edit]: There appears to be some new data for #3

 

[shogun338]

A fire broke out at Japan's crippled Fukushima Daiichi nuclear power plant, operator Tokyo Electric and Power (TEPCO) said on Tuesday, although flames and smoke were no longer visible. http://www.reuters.com/article/2011/04/11/idUSL3E7FB1YD20110411

 

[shogun338]

Magnitude 6.6 - EASTERN HONSHU, JAPAN
2011 April 11 08:16:13 UTC http://earthquake.usgs.gov/earthquakes/eqinthenews/2011/usc0002n9v/

 

[Astronuc]

They just had a mag 6.2 down near the Tokai plant.
http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/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/tsunamiupdate01.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]

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/tsunamiupdate01.html

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]

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

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.

"

http://www.f.waseda.jp/okay/news_en...ower_Plants_suffered_big_eart_quake110331.pdf

Pg5
Emergency DGs started at the earthquake. But Tsunami damaged ultimate heat sinks (sea water pumping and cooling system) of units 1F1-4. caused common cause failure
•Without ultimate heat sink, Emergency DG (need to remove its generated heat for operation) and spent fuel pool cooling do not work.

Pg6
2:46pm: The earthquake happened. Plants automatically shut down. Offsite power lost. Emergency DG started up.
•3:42pm Emergency DG(diesel generator) stopped due to loss of equipment cooling water. (Tsunami was bigger than expected.) All AC power was lost for 1F1-4 and consequential isolation from UHS(ultimate heat sink), except for IC (isolation cooling system) in 1F1. RCIC(reactor core isolation cooling system) in 1F 2 Blackout + (mostly) loss of UHS"

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