Japan Earthquake: Nuclear Plants at Fukushima Daiichi

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The Fukushima Daiichi nuclear plant is facing significant challenges following the earthquake, with reports indicating that reactor pressure has reached dangerous levels, potentially 2.1 times capacity. TEPCO has lost control of pressure at a second unit, raising concerns about safety and management accountability. The reactor is currently off but continues to produce decay heat, necessitating cooling to prevent a meltdown. There are conflicting reports about an explosion, with indications that it may have originated from a buildup of hydrogen around the containment vessel. The situation remains serious, and TEPCO plans to flood the containment vessel with seawater as a cooling measure.
  • #12,211
Sorry for the off-topic, but what were the applications of uranium at the time of that "old uranium mine (from the war)" in Fukushima prefecture ?
 
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  • #12,213
their Manhattan Project was moved to North Korea because we kept bombing Tokyo where their labs were located..
It's believed that at war's end it was packed up and sent to Stalin.
though old anecdotes of a test exist.

One can search for some of Dr Paul Kuroda's memoirs. He was a minor researcher in Japan's bomb effort who came here after the war, worked on astrophysics.

old jim
 
  • #12,214
rowmag said:
The other possibility that occurs to me is that there is also an old uranium mine (from the war) in Fukushima near the airport, and there is also a radon onsen near there, so maybe it is possible the wind blew some radon from there instead. Not as directly upstream of Tsukuba as F1 was at the time of the spike, but not completely out of the stream either. I'll post some wind maps later to show what I mean.

After doing some more research, it turns out there are several radon onsens dotted around the eastern half of Fukushima prefecture, including one in Hirono, about 20 km south of the Fukushima Daiichi power plant. So, there are likely to be uranium ores distributed over a rather wide area in the ground. In fact, there is even a radon onsen in Mito in Ibaraki prefecture, much closer to Tsukuba than anywhere in Fukushima, and also upwind of it that day.

So, unless someone has a calculation showing that the expected radon concentration from Fukushima Daiichi should be much higher than that from the natural emanations coming out of the ground in the general region, the significance of these precipitation-related radiation spikes would seem to be inconclusive.
 
  • #12,216
http://www3.nhk.or.jp/news/genpatsu-fukushima/20120128/index.html on 28 January at 10:30, a 9 litre leak was found close to one of the 3 pumps that inject water into the reactors. The leak stopped after shutting the pump down. There was no flow into the sea. Then near noon, two other leaks were found on valves at the water processing facility. In both cases a few litres of processed water leaked, but remained inside the building(s).
 
  • #12,217
News seem to dry up, but there should be some activity.

For example, what's the status of basement water level reductions? How many tons are still there?

The plan was to seal off reactor building basements, to at least stop leaking into turbine buildings and further into the ground. Is there progress?

On this video I see that TEPCO is doing something around Unit 4:


Are these preparations for dismantling the ruined top part?
 
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  • #12,218
Thanks for these questions nikkkom and I hope there is some activity. I asked something similar already, as I wonder if enough progress is made. Well, one could also wait 300 years until most of the radioactive stuff has decayed away...

And I also wonder about the plan for the accumulated water. There is still a high inflow of groundwater and soon the storage tanks will be full. And then?
 
  • #12,219
Afaik, the JAIF provides the best ongoing summary of the situation on its web site.
http://www.jaif.or.jp/english/
It indicates some 200,000 cubic meters of water have been treated, but the ongoing influx of groundwater means 80,000 cubic meters remain in the facility continually.
TEPCO is building a sea wall to seal off the site from the ocean, but the larger issue of sealing off the entire site from groundwater has yet to be tackled. It is not happening imho because it would be a monster job whose utility could be destroyed in an instant by another small earthquake.
The cleaned water probably will eventually be used as irrigation water, as the idea of dumping it into the ocean has encountered objections by the local fisheries. There is no public plan for what to do with the concentrated waste water or the contaminated filters and sludge material.
 
  • #12,220
nikkkom said:
News seem to dry up, but there should be some activity.

For example, what's the status of basement water level reductions? How many tons are still there?

Their mid-term goal is not to reduce water levels but to keep them stable : "based on the view of limiting inflow of underwater to buildings and reducing the amount of emerged accumulated water, we are planning to transfer accumulated water keeping its level in the building below OP. 3,000 considering water tank capacity." : http://www.tepco.co.jp/en/press/corp-com/release/betu12_e/images/120125e5.pdf
nikkkom said:
The plan was to seal off reactor building basements, to at least stop leaking into turbine buildings and further into the ground. Is there progress?
On http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/111221e14.pdf page 42/94, "Target:Complete Switch to Water Withdrawal from Reactor Building (or lower part of PCV)" is set for mid-fiscal year 2015. There is also "(HP1-1): Completion of stopping inter-building water leakage between reactor and turbine buildings and repairing lower part of the PCV" which is planned for the middle of phase 2 around 2017. On page 48/94 you can see that "R&D for PCV Leakage Point Survey/ Repairs (including stopping inter-building water leakage)" is scheduled for fiscal years 2012-2013-2014 including "Design, Manufacture and Test, etc. of PCV Leakage Point Survey Equipment ②" and "Design, Manufacture and Test, etc. of PCV Repair Equipment ③⑥", with "Investigation of Leakage Points (including field test of R&D results)" starting in mid fiscal year 2014.

In the documents of the mid-long term meeting of 26 December you can find a slideshow about accumulated water : http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/m111226_08-j.pdf page 16/37 - 24/37. It is divided into 3 parts:

1) Radical countermeasures against inflow of groundwater : they want to repair the subdrains that were damaged by the tsunami, then decontaminate them, and finally pump ground water from the subdrains to control ground water level and reduce ground water inflow into the turbine buildings.
2) Increase removal capacity and secure stable operation of decontamination facility
3) Further install on-land equipments. (The red areas are already used. The blue areas are still free for adding more tanks)

There was a second mid-long term meeting on 23 January. The documents are available on Japanese only (as far as I know) at http://www.tepco.co.jp/nu/fukushima-np/roadmap/conference-j.html (for example including the following presentations on mock-up debris : http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/r120123_04-j.pdf and water treatment secondary waste products (sludge, zeolite) : http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/r120123_05-j.pdf and an announcement of a workshop on fuel removal techniques (open to the public and press) to be held on 24 February http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/r120123_06-j.pdf ).

There is also a detailed review of what was done during the past 30 days up to January 23, and what they plan to do in the coming months at http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/m120123_05-j.pdf, which includes a report on the water levels of unit 4 pool, drywell pit, and skimmer surge tank, and another report on the installation of new water-treatment facilities (tanks, or waste storage areas), and new areas to store wood from the cleared forests. The trial run of unit 3's PCV gas managing system is scheduled for February 23. The "basic design of shortening the water injection loop" is mentioned as a continuous line from January through April, or possibly later. The basic design of the multi-nuclide removal equipment [1] ends at the end of January, and the detailed design of the same starts in February. A forest clearance is more or less scheduled at the end of February in connection with this multi-nuclide thing. A subdrain purification test was started at unit 2 in the second week of January. There is a plan to change the seismic isolated building into a zone outside the controlled area, which means decontaminating (like cleaning the roof) and shielding the building (with steel and lead sheets). The design for the shielding ends at the end of January. At unit 4 reactor building, in January, they took care of the top part of the operating floor crane and removed rows R5 and R6 of the roof steel frame [this is on the south side]. In February they will remove rows R3 and R4, and remove "big machines" from the operating floor. They will start removing unit 4's north side wall and steel frame at the end of March.

[1] an equipment that would remove strontium, according to http://www.japantimes.co.jp/text/nn20120112a9.html

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120129/index.html On 29 January Tepco announced 14 leaks [!]. It is believed that these leaks are due to the frost. One of them is a 40 litre leak found at unit 4 at 9:30 AM. Another one is a 600 litre leak found near one of the pumps that inject water into the reactors. Another one is a 7 ton leak of the circulating water of unit 6 (not contaminated). In the morning of 29 January, the temperature was 8°C of frost. Tepco's Junichi Matsumoto said "the freezing countermeasures are far from being sufficient. It is necessary to install heat insulating material at a higher pace than until now".

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120129_01-e.pdf "Water leakage in Fukushima Daiichi Nuclear Power Station (Discovered on 29 January)"

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120129_02-e.pdf (map of the leaks)
 
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  • #12,221
etudiant said:
Afaik, the JAIF provides the best ongoing summary of the situation on its web site.
http://www.jaif.or.jp/english/
It indicates some 200,000 cubic meters of water have been treated, but the ongoing influx of groundwater means 80,000 cubic meters remain in the facility continually.

Uhhh... that's an awful lot of water. The influx is so large? Why?

the larger issue of sealing off the entire site from groundwater has yet to be tackled. It is not happening imho because it would be a monster job whose utility could be destroyed in an instant by another small earthquake.

Did it occur to TEPCO to drill a few dozen drainage wells and pump them out?

Do they really plan to keep basements drenched wet for five years or more? That stuff wasn't designed for this environment! Everything will rust into dust!
 
  • #12,222
etudiant said:
The cleaned water probably will eventually be used as irrigation water, as the idea of dumping it into the ocean has encountered objections by the local fisheries.

Somehow I think local farmers won't be happy either. In fact, dumping this very slightly contaminated water into the ocean is the best idea. If this will not be allowed, is it economical to distillate it once more?
 
  • #12,223
nikkkom said:
...is it economical to distillate it once more?
IIRC the remaining contamination is partly Tritium, which cannot be removed easily.

nikkkom said:
Did it occur to TEPCO to drill a few dozen drainage wells and pump them out?
To prevent further contamination outside the containment they prefer water flowing in. This way they will have to deal with some more water: the other way would mean awful lot of contaminated ground beneath the buildings.

It's a kind of similar system which used in biology or chemistry. Inflow is better when you want to keep something inside.
 
  • #12,224
http://www3.nhk.or.jp/news/genpatsu-fukushima/20120130/2130_4kasyo.html Tepco found 4 more leaks in the night of 29 January and on 30 January. The temperature in the morning of 30 January was 8.7°C of frost. Tepco is reinforcing patrols and covering pipes and equipments with insulating material. Junichi Matsumoto said "as the severe frost is expected to continue, we want to urgently take countermeasures against freezing in the places that were not reached by those countermeasures".

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120130/0730_mizumore.html The NISA has ordered Tepco to take countermeasures against frost in response to the 14 leaks discovered on 29 January, implying a 1 hour 40 minutes stop of unit 4's cooling system. In all cases either pipe junctions were loosened or parts were broken by the expansion of water caused by freezing. Tepco is increasing patrols, adding insulating material and, in some cases, heaters. At the important equipments such as those that perform reactor cooling and those that involve highly contaminated water, the countermeasures are almost complete, but as the frost is expected to continue for several days, Tepco is hurrying up with the remaining countermeasures.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120130/1845_robo.html Chiba institute of Technology has developped robots Quince No.2 and No.3. They were urgently developed after Quince No.1 had its cable entangled and could not move any more inside unit 2 in October. They have nearly the same shape and size as Quince No.1, but cable entanglement is being made more difficult. In case cable communication is impossible, they can communicate with another robot by radio. Quince No. 2 is equipped with a high sensitivity radiation measurement equipment, and Quince No. 3 with a scanner to measure distances. Quince No.2 and No.3 will start being used in mid-February.

http://www.tokyo-np.co.jp/article/feature/nucerror/condition/list/CK2012012902000091.html?ref=rank [29 January] During the week from 22 January to 28 January, the cesium released into the atmosphere by Fukushima Daiichi increased in comparison to the December level. The radiation released by units 1, 2, and 3 all together was 72 million Bq/hour , which is 12 million Bq/hour higher than in December. It is said that as more work was done inside units 2 and 3, the cesium accumulated on the floor soared into the air. Until then cesium release quantities had been steadily decreasing. Tepco said "It is difficult to dramatically decrease the releases. For the time being, the present level will be continuing". To prevent the spreading of the cesium accumulated on the sea floor, the sea floor in the harbour in front of the plant will be covered with a 60 cm thick layer of clay and cement. This work will be done from mid-February to March.

http://www.asahi.com/national/update/0130/TKY201201300070.html According to a November survey, the cesium concentration in the sea floor in the harbour is up to 1.6 million Bq/kg. The 60 cm thick cement layer will cover a 7 Ha area. The local fishing cooperatives had expressed worries that the construction work of the ground water shielding wall would spread cesium into the sea.
 
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  • #12,225
Thanks tsutsuji!

By the way, what happened to Quince No.1, was it left in Unit 2?
 
  • #12,226
tsutsuji said:
http://www3.nhk.or.jp/news/genpatsu-fukushima/20120130/2130_4kasyo.html Tepco found 4 more leaks in the night of 29 January and on 30 January. The temperature in the morning of 30 January was 8.7°C of frost. Tepco is reinforcing patrols and covering pipes and equipments with insulating material. Junichi Matsumoto said "as the severe frost is expected to continue, we want to urgently take countermeasures against freezing in the places that were not reached by those countermeasures".

http://www.tokyo-np.co.jp/article/feature/nucerror/condition/list/CK2012012902000091.html?ref=rank [29 January] During the week from 22 January to 28 January, the cesium released into the atmosphere by Fukushima Daiichi increased in comparison to the December level. The radiation released by units 1, 2, and 3 all together was 72 million Bq/hour , which is 12 million Bq/hour higher than in December. It is said that as more work was done inside units 2 and 3, the cesium accumulated on the floor soared into the air. Until then cesium release quantities had been steadily decreasing. Tepco said "It is difficult to dramatically decrease the releases. For the time being, the present level will be continuing". To prevent the spreading of the cesium accumulated on the sea floor, the sea floor in the harbour in front of the plant will be covered with a 60 cm thick layer of clay and cement. This work will be done from mid-February to March.


Yamanote said:
Thanks tsutsuji!

By the way, what happened to Quince No.1, was it left in Unit 2?

So the theories of piping problems with freezing that was being discussed on this thread months ago appear to have had a pretty significant impact. Why wasn't this forseen?


I also found this interesting - Tepco said "It is difficult to dramatically decrease the releases. For the time being, the present level will be continuing"

If the levels are up because of the work in R2 and R3 (and I am not aware of any plans to perform that work again in the near future) why would the levels remain so elevated?

And @Yamanote - Quince 1 is still in the building where it ceased operations, in one of the articles I read it said that they currently have no plans to retrieve it.
 
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  • #12,227
thebluestligh said:
So the theories of piping problems with freezing that was being discussed on this thread months ago appear to have had a pretty significant impact. Why wasn't this forseen?
In a word - triage. Tepco fixed the big problems as quickly as possible, without being held back by looking for perfection, in the knowledge that lesser problems might arise that would have to be dealt with. I'd argue that these leaks have NOT had a "pretty significant impact" - in fact, essentially no impact in practical terms.

I also found this interesting - Tepco said "It is difficult to dramatically decrease the releases. For the time being, the present level will be continuing"

If the levels are up because of the work in R2 and R3 (and I am not aware of any plans to perform that work again in the near future) why would the levels remain so elevated?
The levels are not particularly elevated. This is "the present level continuing" - 20% variations are nothing much, compared to the previous reductions. There will be continuing work on the sites, so variations in this range may well continue.
 
  • #12,228
http://www3.nhk.or.jp/news/genpatsu-fukushima/20120131/1305_mizumore.html The temperature in the morning of 31 January was 4°C of frost. One 20 liter leak was found after 9 AM at the junction of pipes of the system bringing fresh water to the decontamination facility. After 11 PM on 30 January a crack was found on one valve on a pipe which brings water into the reactors, but there was no leak. Junichi Matsumoto said "The plan was to finish the countermeasures by next month. Retrospectively it was too late. We want to hurry up with the countermeasures".
 
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  • #12,229
Yamanote said:
what happened to Quince No.1, was it left in Unit 2?

yes it was
 
  • #12,230
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201201310043
This rather convoluted article from Asahi Shimbun was featured on enenews. Apparently

Piping and support structures at the No. 5 reactor of the crippled Fukushima No. 1 nuclear power plant did not have sufficient anti-quake strength under new government standards revised in 2006.

If I understand the article correctly, the calculations needed to determine this rather interesting fact were only just completed a few days ago.
 
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  • #12,231
zapperzero said:
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201201310043
If I understand the article correctly, the calculations needed to determine this rather interesting fact were only just completed a few days ago.

The contrived headline to confuse some theoretical quake with the actual event and the breathless recounting of forces to theoretical pipes under those imagined conditions misses the opportunity to actually inform us about the condition of the real structures at reactor #5. Based on past experience, if there was anything actually wrong, that would have been described in the most dramatic terms possible, so I'll assume, for now, that the structures at unit 5 are in reasonably good shape.
 
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  • #12,232
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201201300001 The multi-nuclide purifying facility will cover "also strontium, cobalt and manganese". They will "start installing equipment in March".

http://www.asahi.com/national/update/0128/TKY201201280396.html But the "detailed design" of the multi-nuclide facility has yet to be done. Radioactive substances are adsorbed on minerals or resins. By selecting adsorption enhancing chemicals, one can change which radioactive substances are removed.

http://www.jiji.com/jc/c?g=soc_30&rel=j7&k=2012013101023 In the report to NISA, Tepco said that the 125 liter highly radioactive water leak in December (containing strontium, flowing into the sea) had been caused a deformation of a gum packing, caused by bubbles, caused by a mistake in the operation manual.

http://www.tepco.co.jp/en/press/corp-com/release/12013108-e.html Report to NISA about the December strontium-water leak at the desalinating facility

http://www.tepco.co.jp/cc/press/betu12_j/images/120131g.pdf Attachment 7 page 24/46 mentions a "water-hammer effect".
 
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  • #12,233
News on the Quince robots: http://is.gd/vkiFXy
 
  • #12,234
tsutsuji said:
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201201300001 The multi-nuclide purifying facility will cover "also strontium, cobalt and manganese". They will "start installing equipment in March".

http://www.asahi.com/national/update/0128/TKY201201280396.html But the "detailed design" of the multi-nuclide facility has yet to be done. Radioactive substances are adsorbed on minerals or resins. By selecting adsorption enhancing chemicals, one can change which radioactive substances are removed.

Does it mean, that there is really no such facility available all around the world right now? Hard to believe for me.

Or is it again about saving money for Tepco - just remove the caesium and pour the rest into the ocean...?

And finally it surprises me that Tepco is surprised about frost in January.
 
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  • #12,235
Questions
Since cesium (radio active or non radioactive) gets absorbed by plants and animals as a nutritional supplement in place of potassium and becomes part of the World food chain.
Will this not effect health by lack of potassium levels and or by way of cell damage from cesium exposure? If so,

It stands to reason that the cesium plumes in the environment will continue to spread in concentrations by way of plant, animals, the wind and ocean currents, eventually becoming evenly dispersed throughout the planet.

Has anyone determined how much of this cesium can exist in the food chain or has anyone projected future cesium levels in the environment?

Another question regarding the use of cesium in the environment.

If we have all of these environmental agencies conducting test for the monitoring and protection of our atmosphere, land, and oceans.
How can their test and experiments be viable if certain agencies that are protected by national security waivers release huge amounts of cesium into the environment without disclosure to those agencies?

Do they really think that by burying it in mud and clay will stop it? Do biological life forms not exist in mud and clay?

Really now, what is the point of monitoring, measuring, and mapping cesium contamination, when the governments keep secret what has been contaminated in secret?

http://www.stripes.com/news/pacific/earthquake-disaster-in-japan/more-cesium-found-in-rice-harvested-in-fukushima-in-japan-1.161770
 
  • #12,236
Sled Head said:
Questions
Since cesium (radio active or non radioactive) gets absorbed by plants and animals as a nutritional supplement in place of potassium and becomes part of the World food chain.
Will this not effect health by lack of potassium levels and or by way of cell damage from cesium exposure?

No, it won't. Plants will continue to absorb mostly potassium. Caesium is absorbed in very, very small amounts.

If so,

It stands to reason that the cesium plumes in the environment will continue to spread in concentrations by way of plant, animals, the wind and ocean currents, eventually becoming evenly dispersed throughout the planet.

Has anyone determined how much of this cesium can exist in the food chain or has anyone projected future cesium levels in the environment?

Another question regarding the use of cesium in the environment.

If we have all of these environmental agencies conducting test for the monitoring and protection of our atmosphere, land, and oceans.
How can their test and experiments be viable if certain agencies that are protected by national security waivers release huge amounts of cesium into the environment without disclosure to those agencies?

What "huge amounts" of caesium are you talking about? Caesium is not poisonous. Total inventory of caesium, all isotopes combined, in the fuel on the whole F1 site is on the order of 100 kg. Its danger comes solely from its radioactive isotopes, not chemical/biological effects.
 
  • #12,237
http://www.tokyo-np.co.jp/s/article/2012020190070438.html On 31 January, the NISA announced that during the 11 March earthquake, the Emergency Response Support Systems (ERSS) were temporarily suspended at 3 nuclear power plants, because their emergency uninterruptible power systems (systems with batteries inside) were not connected : Tokai Daini, Onagawa, and Higashidori nuclear power plants. Tokai Daini's ERSS was interrupted for more than 3 hours, and at Onagawa and Higashidori the signals were unstable for 8 and a half hours. The NISA found the emergency uninterruptible power system disconnection at Fukushima Daiichi in May, but did not start checking other plants until 7 months later.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120131/index.html Two more leaks were found at Fukushima Daiichi in the afternoon of 31 January. One 10 liter leak at a reactor injection backup pump, and a 20 liter leak at a "tank pipe". Both leaks are with water devoid of radioactive substances.
 
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  • #12,238
http://translate.google.com/translate?hl=en&sl=auto&tl=en&u=http%3A%2F%2Fwww.tokyo-np.co.jp%2Farticle%2Fnational%2Fnews%2FCK2012013102000038.html

http://translate.google.com/translate?hl=en&sl=auto&tl=en&u=http%3A%2F%2Fwww.tokyo-np.co.jp%2Fs%2Farticle%2F2012013190071414.html

Re - Frozen piping
 
  • #12,239
Joffan said:
misses the opportunity to actually inform us about the condition of the real structures at reactor #5

According to the article, there is a survey in progress. Perhaps results will be published later.
 
  • #12,240
""http://www.tepco.co.jp/cc/press/betu12_j/images/120131g.pdf Attachment 7 page 24/46 mentions a "water-hammer effect".

what equipment is that fractured pipe?
 

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