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Japan Earthquake: nuclear plants part 2

  1. Sep 20, 2013 #1
    Part 1 can be found here:

    Magnitude-5.3 earthquake hits Japan's Fukushima

  2. jcsd
  3. Sep 20, 2013 #2
    What is the reason for thread closure, please?
  4. Sep 20, 2013 #3
    Not closed, moving to part 2. After 14k posts it becomes a system performance issue.
  5. Sep 21, 2013 #4


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    If that is the case, can it get pinned?

    Although long, it is probably THE best resource on the web for the events there and it would be a waste for it to drop down the page list.
  6. Sep 21, 2013 #5


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    http://www3.nhk.or.jp/news/genpatsu-fukushima/20130921/index.html On 17 September, Tepco found 5 loosened bolts in the bottom plates of the tank, which is being dismantled. That could be the leakage cause. They also found resin deformation and rust in different locations, which might also have been causal. There is no way to directly inspect the other 300 or so tanks, and it is impossible to replace them immediately. For that reason, Tepco is reinforcing the monitoring.
  7. Sep 21, 2013 #6


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  8. Sep 21, 2013 #7


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  9. Sep 21, 2013 #8
    EDIT: also, is it possible to post an archive of it somewhere, now that it is closed and the archive would no longer need to be updated? I'd hate for it to someday go the way of the unit 3 explosion thread...
    Last edited: Sep 21, 2013
  10. Sep 24, 2013 #9


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    Gregory Jaczko conference in Tokyo today.
  11. Sep 25, 2013 #10
  12. Sep 25, 2013 #11
  13. Sep 26, 2013 #12
    Sorry for the wholly unscientific questions, but ... Assuming fuel removal goes well at the Unit 4 pool, does TEPCO then still have to build a similar structure(s) for Unit 3 or otherwise reconstruct the fuel removal equipment to remove the pool contents? What about Unit 1 and 2's building integrity/removal equipment for the fuel pools?
  14. Sep 26, 2013 #13
    Yes, Units 3 and 1 will need something similar - after debris is removed, surfaces (the floor, for example) decontaminated and repaired.

    Repair - new layers of concrete - in this case will also work as shielding - a lot of beta contamination by now seeped into concrete and is impossible to remove.

    Unit 2 is physically intact but very contaminated - IIRC, close to 1000 rem/h on the refueling floor.
  15. Sep 26, 2013 #14


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    http://www3.nhk.or.jp/news/genpatsu-fukushima/20130926/1145_minaoshi.html As a follow-up of the stack crack problem, the NRA instructs Tepco to revise the assumed maximum earthquake. Before the accident, the stack had been assessed as being safe under the assumed maximum earthquake. For that purpose, Tepco will make plans to investigate active faults. If the assumed maximum earthquake is revised, all earthquake safety assessments, for example of reactor buildings, have to be done again.

    http://www3.nhk.or.jp/news/genpatsu-fukushima/20130926/1145_saikai.html Water treatment facility ALPS's hot testing has been started again today. It had been suspended as a consequence of a leak, which had been caused by corrosion. The test is starting on the line where corrosion countermeasures have been implemented. The other two lines will be started one after another, starting in mid-November. The resulting treatment capacity will be 500 ton/day. Under the government funded plans, the treatment capacity will be brought to 1500 ton/day within next fiscal year. However there is still no decision taken concerning what to do with the resulting tritiated water.

    http://www3.nhk.or.jp/news/genpatsu-fukushima/20130926/1145_tunk.html (26 September 2013) Tepco found a gap between bottom plates on the location where loose bolts had been found. The gap was found by using a chemical that makes bubbles and by watching the bubbles being sucked into the gap.

    http://www.tepco.co.jp/en/nu/fukushima-np/handouts/2013/images/handouts_130920_09-e.pdf (20 September 2013) Investigation of the Inside of Tank No.5 in H4 Area

    http://www.tepco.co.jp/nu/fukushima-np/handouts/2013/images/handouts_130830_10-j.pdf (30 August 2013) H4 area tank leakage (36 pages, Japanese)

    http://www.tepco.co.jp/nu/fukushima-np/handouts/2013/images/handouts_130926_04-j.pdf After a qualification test on 20 September, on 24 September a robot measured water level inside unit 2 suppression chamber. The results are currently being assessed.

    http://www.tepco.co.jp/nu/fukushima-np/handouts/2013/images/handouts_130912_11-j.pdf (12 September 2013) Qualification test for the suppression chamber inner water level measurement robots. The robots are equipped with ultrasonic sensors. The test is performed at unit 5. There are two kinds of robots : a fixed type and a moving type.
    Last edited: Sep 26, 2013
  16. Sep 28, 2013 #15


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  17. Sep 28, 2013 #16
    When following the various events and "informations" about this disaster since the very beginning, it's astounding to try to list the number of "inconsistencies" (or lies?) that have been explained by the various actors, Tepco being the number one but the government being a close number two...

    Two examples:

    -Tepco revised recently their assessment of the daily volume of groundwater flowing into the plant from the mountains, the volume that they had to pump and consequently the volume of contaminated groundwater that flows everyday directly to the sea: 800 m3 should come from the mountains, 400m3 are pumped and stored, and 400m3 would consequently flow directly to te sea. Well. The problem is that Tepco also confirmed that before the accident, they were pumping between 850 and 1200m on a daily basis to avoid inputs of groundwater inside the basements of the buildings because of the way the plant was erected: the 30m hill above see level was transformed to the platform 10m high that we know (probably to lower the energy required to pump in the seawater used for cooling the reactors, making it vulnerable to high amplitude tsunamis as we know). So how could it be 800 m3 today if the volume pumped before the accident was already 850 to 1200 m3?

    - Tepco apparently confirmed recently that reactors 5 and 6 are pumping 6000 m3 every hour to cool the reactors INTO THE PORT, and rejecting them OUTSIDE OF THE PORT... Tsutsuji, could you confirm this info from the links given here (in japanese)?


    If true, how can it be possible (we know it's not!) to say that contaminated water is enclosed into the port (Tepco didn't say it, but Abe did!) ??

    EDIT: the link to this document from August 2013 is said to refer to a coolant volume à 7000 m3/h (which is huge?) for 5 and 6 but i didn't find the data in the document (i don't read japanese, even if numbers are the same!). But page 58 seem to show a map with arrows to represent the various flows, but i don't understand all the details (is there a kind of dam between side of the port toward reactors 5 and 6 and the other ones, like this red line between the two sides of the port seems to suggest?)

    Last edited: Sep 28, 2013
  18. Sep 28, 2013 #17


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    http://www3.nhk.or.jp/news/genpatsu-fukushima/20130927/index.html The "International Research Institute for Nuclear Decommissioning", a foreign specialist research group, had a meeting in Tokyo on 27 September. Englishman Adrian Simper said the consequences of a frozen soil wall must be carefully studied before taking the decision to build one or not. Tepco vice president Aizawa said that as a frozen wall could be the "trump card" to solve the issue, careful steps such as making an experiment, will be taken. Also opinions were expressed saying that removing the contaminated water from the trenches and repairing the drain system have the highest priority. Adrian Simper said that no countermeasure is devoid of counter effect or uncertainty, so that risk and uncertainty have to be discussed.

    http://irid.or.jp/cw/ Request for Information for Contaminated Water Issues (English)

    http://www3.nhk.or.jp/news/genpatsu-fukushima/20130927/2049_senmon.html A national specialist council was convened on 27 September. They released a plan with additional countermeasures addressing risk associated with contaminated water issues. It includes equipping the basements with pumps to control water levels, and preparing the method to quickly transfer water into another facility in the case a leak occurs in a storage tank. Secondary countermeasures are also requested to prepare for the case when primary countermeasures are not working smoothly. The plan is still being discussed. As member(s) said "the ground water flow is still unknown", it was decided to create a specialist team to address ground water flow and the spread of contamination. The specialist council will perform an onsite surveys and review available technology from Japan and abroad. They plan to reach conclusions on risk and responses by the end of this year.

    http://www.meti.go.jp/earthquake/nuclear/20130927_01.html The 7th contaminated water treatment countermeasure committee, 27 Septembre 2013

    http://www.meti.go.jp/earthquake/nuclear/pdf/130927/130927_01a.pdf Agenda
    http://www.meti.go.jp/earthquake/nuclear/pdf/130927/130927_01b.pdf Participants
    http://www.meti.go.jp/earthquake/nuclear/pdf/130927/130927_01c.pdf Study of countermeasures for contaminated water problem risk elimination
    http://www.meti.go.jp/earthquake/nuclear/pdf/130927/130927_01d.pdf Points to be discussed toward the within-this-year reach of conclusions
    http://www.meti.go.jp/earthquake/nuclear/pdf/130927/130927_01e.pdf Onsite progress status concerning the contaminated water problem​

    The NRA has its own Fukushima Daiichi contaminated water working group. Here is their last meeting :

    http://www.nsr.go.jp/committee/yuushikisya/tokutei_kanshi_wg/20130912.html [Broken] The 6th special nuclear facility study committee, contaminated water countermeasure working group, 12 September 2013

    http://www.nsr.go.jp/committee/yuushikisya/tokutei_kanshi_wg/data/0006_99.pdf [Broken] Agenda
    1-1 http://www.nsr.go.jp/committee/yuushikisya/tokutei_kanshi_wg/data/0006_01.pdf [Broken] Basic principles as regards the contaminated water problem
    1-2 http://www.nsr.go.jp/committee/yuushikisya/tokutei_kanshi_wg/data/0006_02.pdf [Broken] Outline of the basic principles as regards the contaminated water problem
    1-3 http://www.nsr.go.jp/committee/yuushikisya/tokutei_kanshi_wg/data/0006_03.pdf [Broken] The 1st contaminated water countermeasure onsite adjustment meeting
    2 http://www.nsr.go.jp/committee/yuushikisya/tokutei_kanshi_wg/data/0006_04.pdf [Broken] Points made by the nuclear regulation agency at the contaminated water countermeasure onsite adjustment meeting
    3 http://www.nsr.go.jp/committee/yuushikisya/tokutei_kanshi_wg/data/0006_05r.pdf [Broken] Contaminated water leakage at H4 tank area (Tepco)
    4 http://www.nsr.go.jp/committee/yuushikisya/tokutei_kanshi_wg/data/0006_06.pdf [Broken] Seawater and groundwater contamination eastwards of turbine buildings : nuclide concentration status and response (Tepco)​
    Last edited by a moderator: May 6, 2017
  19. Sep 28, 2013 #18


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    The "about 6000 m³/hour" data can be found in the press conference transcript at http://genpatsu-watch.blogspot.com/2013/09/20139261730-8.html below timing 00:54:55 when Mr Ono replies to a question about the unit 5-6 silt fence breakup.

    The 7000 m³/h data is from page 60 of the following document :


    Page 58/78


    Attached Files:

    Last edited: Sep 28, 2013
  20. Sep 28, 2013 #19


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    Last edited: Sep 28, 2013
  21. Sep 28, 2013 #20
    Again, great thank you Tsutsuji for the confirmations and the translation of the map!

    So do others here come to the conclusion that through the pumping of 6000/7000 m3/h into the port for cooling reactors 5 and 6, there is inevitably contamination that is therefore rejected directly into the sea at the point of the extreme left blue arrow on the map? It may be one of the reasons why they have erected this wall with tubes along reactors 1 to 4....
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