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Japan Earthquake: nuclear plants

by gmax137
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zapperzero
#12241
Jan31-12, 09:38 AM
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Quote Quote by Yamanote View Post
what happened to Quince No.1, was it left in Unit 2?
yes it was
zapperzero
#12242
Jan31-12, 09:43 AM
P: 1,044
http://ajw.asahi.com/article/0311dis...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.
Joffan
#12243
Jan31-12, 10:40 AM
P: 361
Quote Quote by zapperzero View Post
http://ajw.asahi.com/article/0311dis...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.
tsutsuji
#12244
Jan31-12, 11:27 AM
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http://ajw.asahi.com/article/0311dis...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...201280396.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&re...=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...2013108-e.html Report to NISA about the December strontium-water leak at the desalinating facility

http://www.tepco.co.jp/cc/press/betu...es/120131g.pdf Attachment 7 page 24/46 mentions a "water-hammer effect".
CaptD
#12245
Jan31-12, 11:31 AM
P: 20
News on the Quince robots: http://is.gd/vkiFXy
Yamanote
#12246
Jan31-12, 12:03 PM
P: 68
Quote Quote by tsutsuji View Post
http://ajw.asahi.com/article/0311dis...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...201280396.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.
Sled Head
#12247
Jan31-12, 01:05 PM
P: 5
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/...japan-1.161770
nikkkom
#12248
Jan31-12, 02:37 PM
P: 611
Quote Quote by Sled Head View Post
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.
tsutsuji
#12249
Jan31-12, 05:17 PM
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http://www.tokyo-np.co.jp/s/article/...190070438.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-...131/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.
zapperzero
#12251
Feb1-12, 05:24 AM
P: 1,044
Quote Quote by Joffan View Post
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.
jim hardy
#12252
Feb1-12, 09:19 AM
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""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?
tsutsuji
#12253
Feb1-12, 09:23 AM
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http://www3.nhk.or.jp/news/genpatsu-...201/index.html An 8.5 ton leak was found on unit 4's first floor at 10:30 PM on 31 January. A ⌀ 9mm pipe connected to the reactor was pulled out of a junction part. The radiation of the water is 35.5 Bq/cm³ . The leak was stopped by closing a valve on the reactor side. The water went no further than the reactor building basement. Tepco said "we are unsure if this was caused by frost".

http://www.tepco.co.jp/en/nu/fukushi...20201_01-e.pdf "Status of Water Leakage on the 1st floor of Unit 4 Reactor Building, Fukushima Daiichi Nuclear Power Station (Test line of the Piping for Jet Pump Measurement)"

http://www.47news.jp/CN/201202/CN2012020101002248.html It is thought that the water started leaking at around 5 PM on 30 January. Tepco earlier reported a 6 liter leak, but after checking, announced the quantity was 8.5 tons. The 8.5 ton quantity is inferred from the water level drop in the tank installed on the side of the fuel pool. It is thought that the water expanded by freezing, creating an internal pressure pushing the pipe away.


In the afternoon press conference, Junichi Matsumoto makes a small drawing on the white board and explains to a journalist that the fuel pool's water level remained stable, even though the skimmer surge tank's water level decreased on 30 January by 60 to 90 mm/hour (instead of the usual 3 mm/hour caused by evaporation). Tepco started patrolling the plant to find the leak at 22:00 on 31 January. Junichi Matsumoto agrees with a journalist that this was late, but as the airfin cooler had been adjusted, the operators thought that the water level drop could have resulted of a drop of temperature, and hoped for about 24 hours that the water level would stabilize. When the leak was stopped, the skimmer surge tank water level had dropped by 1.10 m (1 February afternoon press conference video at http://www.tepco.co.jp/tepconews/library/movie-01j.html )

http://www.tepco.co.jp/en/nu/fukushi...l_120201-e.pdf page 3 "There was no Pu-238, Pu-239 and Pu-240 detected from the sample for this analysis" [north water intake canal Units 1-4 Fukushima Daiichi Nuclear Power Station, 16 January]

http://www.tepco.co.jp/en/nu/fukushi...l_120201-e.pdf "Radioactive density of the Pu-239 and Pu-240 detected on January 16 was within the same level as that of fallout of past nuclear test in the atmosphere." [soil]

http://www.tepco.co.jp/en/nu/fukushi...u_120201-e.pdf page 145/148 : 3.1E-05 Bq/cm³ of Ag-110m in the air at Upper part of reactor building of Unit 3 on 6 January

http://www.tepco.co.jp/en/nu/fukushi...u_120201-e.pdf page 115/148 : 5.3 E-02 Bq/cm³ of Ru-106 in unit 3 subdrain on 11 January. (Ru-106 had been previously found in soil and dust samples in March, Junichi Matsumoto says in the 1 February afternoon press conference video at http://www.tepco.co.jp/tepconews/library/movie-01j.html )

http://www.tepco.co.jp/en/nu/fukushi...20201_03-e.pdf "Measures against Freeze of Water Treatment Facility / Measures against Freeze of Reactor Water Injection System at Fukushima Daiichi Nuclear Power Station" ["floodlight", on page 3, is a well coined English word]

http://mainichi.jp/select/jiken/news...40080000c.html Tepco found 158 mistakes in the stress test report sent to NISA for Kashiwazaki Kariwa units 1 to 7. These are simple mistakes without consequences on the report's conclusions.

Quote Quote by jim hardy View Post
http://www.tepco.co.jp/cc/press/betu...es/120131g.pdf Attachment 7 page 24/46 mentions a "water-hammer effect".

what equipment is that fractured pipe?
No pipe was fractured. Only a packing was deformed, as you can see on the photographs on attachment 6 page 23/46. The blue equipment (pink equipment on the diagram on attachment 7) is a preheater belonging to an evaporative concentration apparatus.

Quote Quote by Joffan View Post
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.

I tried to have a look at what was said about unit 5's earthquake resistance in the second report to IAEA.

On http://www.iaea.org/newscenter/focus...hapter-2-1.pdf (English) page II-49 there is a "Table II-2-6 Overview of Impact Evaluation on Equipment and Piping Systems important for Seismic Safety (Fukushima Dai-ichi NPS, Unit 5)" with two columns with figures. The left column is the standard earthquake ground motion Ss, and the right column is the simulation result. Some of the figures in the right column are a few percent higher than those in the left column. Is it dangerous ? There is also a small peak on one of the plots on the same page marked with "peak considered to be generated according to the simulation analysis" and I am unsure what this means.
Attached Thumbnails
unit 4 leak.jpg  
Joffan
#12254
Feb1-12, 11:13 AM
P: 361
Thanks tsutsuji, great reference. Those tables are discussed very briefly on p II-42/3:
Based on the comparison results, according to TEPCO, it was found that for Units 1 to 3, and 5, some of those indexes such as seismic load by the earthquake exceeded the ones from the seismic safety assessment. However, a seismic assessment of major components that have important safety functions relevant to "Shutdown" and "Cool down" of reactors, and "Containment" of radioactive materials was performed, and found that the calculated stress, etc. were below the criteria (Tables II-2-2 to II-2-7). For Units 4 and 6, it was found that those indexes such as seismic load by the earthquake, except some peak floor response spectra, were below the ones from the seismic safety assessment.
And also, a seismic assessment of the piping systems using floor response spectra was performed, for Units 1 to 6, and found that the calculated stress was below the criteria (Tables II-2-8 to II-2-13).
jim hardy
#12255
Feb2-12, 01:04 AM
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"""No pipe was fractured. Only a packing was deformed, as you can see on the photographs on attachment 6 page 23/46. The blue equipment (pink equipment on the diagram on attachment 7) is a preheater belonging to an evaporative concentration apparatus."'

THANKS, Tsujitsu !

i shoulda looked further...
tsutsuji
#12256
Feb3-12, 04:01 PM
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http://www3.nhk.or.jp/news/genpatsu-...204/index.html On 3 February, a leak smaller than 1 liter was found at a tank containing high strontium concentration. The gamma ray at the surface of the water is 22 mSv/hour and the beta ray is 2000 mSv/hour. The leak was stopped by tightening a bolt. This is the same sort of leak as on 10 January ( http://www.physicsforums.com/showpos...ostcount=12136 ). As there are about 100 such tanks, the NISA ordered Tepco to check them and to take countermeasures. Tecpo is investigating, thinking that as the tanks were urgently built, they were assembled with bolts instead of welding.

http://www.tepco.co.jp/en/nu/fukushi...20203_04-e.pdf "Leakage from water desalinations(RO)concentrated water tank" 3 February

http://www.tepco.co.jp/en/nu/fukushi...20110_03-e.pdf "Water leakage from the concentrated water tank of the water desalinations (reverse osmosis membrane)" 10 January

http://www3.nhk.or.jp/news/genpatsu-...203/index.html The NISA will conduct its first inspection at Fukushima Daiichi since the accident for 3 weeks starting on 6 February. During that period, the status of the inspection will be released to the media.

http://www.jiji.com/jc/c?g=soc_30&k=2012020300467On 3 February, Tepco said that the water level in unit 4's skimmer surge tank was decreasing at twice the usual pace and that there is a high probability that the water is leaking. Tepco is urgently looking for the location of the leak.
Martin Peters
#12257
Feb3-12, 04:42 PM
P: 3
Tepco has posted an English document describing the work they did to reduce the level of radiation in a parking lot: "Radiation dose reduction by collecting dust and small rubbles
at the parking lot in front of Main Anti-Earthquake Building of Fukushima Daiichi Nuclear Power Station"

http://www.tepco.co.jp/en/nu/fukushi...20203_01-e.pdf

The maximum value of radiation at 1 cm above the surface (shown below the lower left chart) appears to be erroneous. According to the color key, the red dots in the chart show locations where the surface radiation was >1000 µSv/hr. Since a comma appears to the left of the digits "240", I suspect that a digit to its left has been lost.

Edit at 0300 UT, 4 Feb 2012: The Japanese version of this doc shows that the value is 1,240 µSv/hr.
tsutsuji
#12258
Feb4-12, 08:43 AM
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Quote Quote by tsutsuji View Post
http://www.jiji.com/jc/c?g=soc_30&k=2012020300467On 3 February, Tepco said that the water level in unit 4's skimmer surge tank was decreasing at twice the usual pace and that there is a high probability that the water is leaking. Tepco is urgently looking for the location of the leak.
The above is dated 2012/02/03-12:54 so it is probably from the morning press conference. I watched the 3 February afternoon press conference video ( http://www.tepco.co.jp/tepconews/library/movie-01j.html ), where Junichi Matsumoto said that after refilling the skimmer surge tank, the dropping rate was around 10 mm/hour which is within the allowed range, taking evaporation into consideration.

I checked the skimmer surge tank water level data at
http://www.tepco.co.jp/en/nu/fukushi..._summary-e.pdf
http://www.tepco.co.jp/en/nu/fukushi..._summary-e.pdf
http://www.tepco.co.jp/en/nu/fukushi..._summary-e.pdf
http://www.tepco.co.jp/en/nu/fukushi..._summary-e.pdf

2997mm on 4 February 05:00
3179mm on 3 February 11:00
(3179-2997)/(24+5-11)=10.1 mm/hour

2318mm on 18 January 11:00
2388mm on 17 January 11:00
(2388-2318)/24 = 2.92 mm/hour

I don't understand why they refilled so little on 3 February (to perhaps between 3000 and 4000 mm, instead of refilling to more than 5000 mm)

In the 4 February afternoon press conference video ( http://www.tepco.co.jp/tepconews/library/movie-01j.html ), Tetsuya Terasawa says that they measured 4 mm between 6:28 and 6:53 in the morning which he calls "a stable 4 mm". He says they reached the conclusion that the variation of skimmer surge tank water level is explained by causes such as evaporation and the volume variation caused by temperature, and is not caused by a leak. The NHK journalist asked if it is 4 mm "per hour", and Terasawa said "yes" (until the NHK journalist asked, I thought it was 4 mm in the 25 minutes from 6:28 to 6:53). He also said that there was a 12 mm/hour drop at 11:00 on 3 February. Tepco has no plan to further investigate the causes of the water level drop, but will carefully survey the skimmer surge tank water level.

http://www.asahi.com/national/jiji/JJT201202040074.html [4 February 22:06] Tepco was studying the possibility of a leak as unit 4's skimmer surge tank water level was decreasing at twice the usual pace on 1 and 2 February, but after refilling the tank, the decrease rate became smaller. Tepco explains the temporarily quick pace with the reduction of volume due to the temperature fall and to the evaporation increase due to dry air.


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