Tepco: New 60-ton cover on top of Unit No. 4 fuel pool installed (PHOTOS)

Published: June 15th, 2012 at 3:26 pm ET


Tepco’s June 15, 2012 Handout: The Protection Platform Installation on Unit 4 Spent Fuel Pool at Fukushima Daiichi Power Station

Subscription Only: Fukushima No. 4 spent fuel pool gets steel plate cover: TEPCO
Kyodo News
June 15, 2012

The operator of the crippled Fukushima Daiichi nuclear power plant said Friday that it has placed a steel plate cover over the spent fuel pool of the No. 4 unit.

[…] to prevent rubble from falling into the pool […]

The 60-ton steel plate is 11 meters long and 13.7 meters wide.


Published: June 15th, 2012 at 3:26 pm ET


Related Posts

  1. Tepco adds 60-ton cover on No. 4 fuel pool (PHOTOS) June 8, 2012
  2. Cover for Fukushima Spent Fuel Pool No. 4 — Tepco starts installing giant steel frame (PHOTOS) January 8, 2013
  3. Nuclear engineer identifies ‘weakest link’ at Unit No. 4 — “Potential catastrophic drain down” of fuel pool (PHOTOS) June 15, 2012
  4. WSJ speculates: “Is process of emptying the Unit 4 pool starting?” — Will Tepco continue taking out more racks? — Law forbids disclosing when nuclear fuel is moved July 19, 2012
  5. 5 Weeks Later: Tepco begins checking fuel assemblies it removed from Unit 4 pool — Says no ‘major’ deformations so far August 27, 2012

35 comments to Tepco: New 60-ton cover on top of Unit No. 4 fuel pool installed (PHOTOS)

  • hmmmm….that should make it easier to access in case something goes wrong…..



  • StPaulScout StPaulScout

    Can anyone hazzard a guess as to why putting 60 tons of steel on a teetering building needed to be done? I'm guessing it has something to do with trying to block radiation, sky shine perhaps? Will this steel cover withstand a fire in the SFP4? Will it block a major radiation release in the event of a fire?

    • getoutwhileyoustillcan

      It's not collapsing fast enough?

    • BreadAndButter BreadAndButter

      Hi, I think it's a reasonable thing to do…on the down left picture, we see the half-destructed roof structure – all of it will have to be demolished, I think. To have a stable cover on the pool surely makes it easier.
      The subconstruction beams under the cover spread its weight quite evenly, I think.

    • andii

      It's just a show…just like the reactor 1 building?
      But getoutwhileyoustillcan could be right and they are trying to hurry up. Either way, not a very good solution 🙁

      • ion jean ion jean

        Why steel to keep out rubble? Why 12,000 lbs of it? They arebo very confident about structural integrity…confident in their measuring devices…confident they didn't just crap their pants…Ha!

    • Sharp2197 Sharp2197

      They want to build a building over this one to install a new crane, this is to keep building materials from further damaging the rods during construction

  • The Blue Light.

    I know i'm really going to get it in the neck for this post but I feel that only the top two floors of building 4 are slanted. I used to be fascinated by optical allusions and pushing over the top two floors would create the allusion that the whole building is tipped over.
    I'm really not trying to be a TEPCO apologist. But I think the chances of the whole building coming down are nil. But the chances of localised damage within the building cracking and then draining the fuel pool are very high, in fact I think this may have already happened in a small way re the reinforcement of the floor of the fuel pool.
    I will now sign off while all nasty comments are made. FIRE AWAY.

    • BreadAndButter BreadAndButter

      I'm also far more worried about the pool than the whole building. It helps the stability of the remaining structure that more and more rubble / walls / roof are removed from the top.

      • …and the cover prevents [more] rubble from falling into the pool. It can always be removed at some point, but no real reason until they get the new structure up for fuel removal.

  • Posted Nuckelchen's vid of the cover placement at Reality Check
    World-wide Fukushima fallout forecasts also there

    Other radiation monitoring links at the rc rad forum

    Senator Wyden's contact info here somewhere. I wonder if he feels better now

  • jec jec

    And this does what? Protect workers from Radiation? Protect environment from emissions? As a 60 ton cap, not sure it will stop any explosive event. Kind of see a giant frizbee sailing high in the sky….

    But because I don't have the nuclear engineering background, hope others on this blog outline what this does..and what it doesn't. At least something was done…for once.

    • I'm going to agree with BandB that it offers some appreciable protection for the pool and what's already in it, from falling debris during the demolition of what's left of the roof, beams, and upper story walls. Thus not a bad idea at all. So long as the pool's full of water and not actively steaming, it shouldn't be emitting much airborne even if the assemblies are broken and rods are split. It probably does emit more gamma/neutron radiation than is healthy. The steel plate will help cut down on that.

    • Ron

      jec: "As a 60 ton cap, not sure it will stop any explosive event. Kind of see a giant frizbee sailing high in the sky…."

      In an explosive event the giant frisbee scenario is much more likely. Chernobyl blew a 1,000 ton roof away (and this in spite of the fact that the nuclear gang has always assured that nuke plants can't possibly cause a large explosion). Fuku has a lot more to explode.

  • Sickputer

    Spent fuel pond 4 and contents is estimated to weigh 3.34 million pounds (1670 tons: bullet 4 on this page:


    They have added a cap that is 120,000 pounds (60 tons).

    The danger of falling debris must be very serious for them to add such a substantial ammount of weight to the precarious pond.

    I hope it helps, but if they think it will help prevent sky shine in a total water failure…I doubt it. It will probably concentrate the runaway spent fuel fallout in a downward direction and prevent any ground remediation.

  • iso-tope iso-tope

    From the mind of TEPCO…

    Problem? What problem? We "covered it up". Out of sight. Out of mind. It is honerable and will save us embarrasment. No radiation. No Blue Orbs…. Oh a structually damaged building missing allmost all 4 walls, with metal toothpick supports can hold 60 tons, especially during a 6.0 earthquake.. Those never happen in Japan. The problem all goes away. No fires, no water leakage, no risk.. It's all good… NOTHING TO SEE HERE.. Now move along….

  • Fred

    60 MORE tons of load on a partially collapsed building?

    Japs think hiding something, out-of-sight, makes unpleasantness and problems go away…same as the tent hiding collapsed R1 from starkly in front of that camera. It's why they are letting the weeds grow high enough to hide R3 pile of rubble and more and more R4 from the cam.

    Soon as we can't see anything on TV, problems will be gone…

  • nuckelchen nuckelchen

    there was an earthquake in the last minutes of the 60 tons-transit.
    you can see the top of the crane is still moving down while it shakes around:

    1. 2012-06-15 tepco placed the steel cover on sfp4


    3. 2012-06-15 earthquaked 60 tons steelplate desaster @ tepco fukushima reactor nr 4

    4. stress-colors on tbs after they had changed the streaming link:

    5. tepcostream down one hour earlier.
    the last 45 minutes as a 20er lapse:
    the last 60 sec in realtime:
    /still uploading…
    and coloredits:
    /still uploading

    • iso-tope iso-tope

      Wow this is crazy. Yes another crane or something to hold it…. BTW Thank you, Nuckelchen for what you do. It's alot of work.

  • gottagetoffthegrid

    in the grand scheme of the structure 60 tonnes isnt much — its equivalent to 25 cubic meters of concrete — less than the weight of one of those big columns they snipped off over the last couple of months.

    the steel plate will protect the assemblies in the SFP from falling debris and peering eyes , but not much else.

    They may be able to get out on top of the plate with a small crane and fish some of the debris out, such as parts of the gantry crane.

    • Sickputer

      GGOTG sez…. "in the grand scheme of the structure 60 tonnes isnt much "

      SP: It's always the last stick of firewood that breaks the camel's back (never did care for the straw maxim).

      GGOTG also sez… "fish some of the debris out, such as parts of the gantry crane."

      SP: Might be possible. But does metal bioaccumulate radiation in the water from 100,000 cracked and/or fused spent fuel rods? I know they were estimating the stranded robot Quince 1 was downright toxic after 7 months stranded in Reactor 2. No water there, but I assume the principle is similar for objects in the SFPs.

      • gottagetoffthegrid

        Steel isnt alive therefore no bio accumulate. It has very low porosity, so not much soak up either ( thankfully) neutron bombardment can induce radioactivity but the pool is subcritical (thankfully) so all they should be worried about is what is stuck to the paint.

        There are a good number of old assemblies in that pool that might be cool enough to move. The need to get those the heck out of there so they don't get re-irradiated if the pool goes LOCA. But there is a lot of crap that fell into that pool. A-fishin is where they need to go

    • BreadAndButter BreadAndButter

      Agreed. Compared to what the structure had to support when the building was still intact 60 tonnes isn't much. En plus, a steel cover is more typhoon safe than the plastic sheet…

  • Heart of the Rose Heart of the Rose

    I'm still thinking about the 60 tons..one crane thing..
    It looks like the rusting corregated roof of my garden shed.

  • Heart of the Rose Heart of the Rose

    After all that hard work …it seems a plastic tarp might have done just as well.
    London Olympics site built on top of heavily contaminated ground, thin plastic sheet


    A couple more articles on the subject.



    • dharmasyd dharmasyd

      Oh Heart of Rose…This is so typical. Contaminate "the fastest, highest, strongest"…whatever, who cares, they're just kids…right?

      They aren't slobs. That term is too soft.

      My mother was a coach at the 1972 Munich Olympics. She brought home a watch she bought for me from the Israeli team; it had Hebrew inscriptions. She never said whether she had bought it from one of those who had been killed. Terrorists? What is a terrorist? Who is a terrorist? And why are they here? And, come to think of it, why are we here? …Except perhaps to stand against this insanity.

      Du must dein leben andern! You must change your life! –Rilke

      We must change this insanity.

      ……..blessings, compassion, and love…..

  • harengus_acidophilus

    Out of sight?
    "[…] to prevent rubble from falling into the pool […]"

    …and to stop pink unicorns from escaping…


    • The Blue Light.

      Oh and don't forget the 'magic moon beams' we don't want any of those pesky little monkeys getting out and causing mischief and cancers and such.

  • pierre

    now they can paint a giant smiley on it that can be seen by astronauts in orbit (that have wisely got off this planet).

    alternatively, its a UFO landing pad for refuelling.

    or they wanted to see if the detection of actually doing something large might be seen by the HAARP players, and maybe trigger a HAARP induced earthquake event whilst they were loading it.

    or they can put a space pod on it that will be ejected into space in the event of a big blow. ♫ build a bonfire, build a bonfire, put the TEPCO's on the top ♫

    dance floor for hysterical Japanese wives?

    // silly rant but what can you do?

  • odylan

    The iron lid should glow if things hot up!

  • AGreenRoad AGreenRoad




    First #1 covered up with tent, no more prying eyes.

    Then cold shut down for everything, (but not really.)

    Deny #3 even blew up, everything still there, no problems, despite no water in sight, no pumps, nothing left to see. Deny 500 pounds of plutonium blew into the air. Deny that it was even there.

    Now #4 has steel plate put on top so no one can check on it. They can drain water out and no one would know the difference. Out of sight, out of mind. Job done, no need to even get the fuel out.




    Time for a bonus and raise, or fancy secret condo in Australia for bamboozling the masses.