Tepco admits high temps may have degraded containment vessels after meltdowns — ‘Massive amounts of fallout’ released from upper part of reactors?

Published: May 24th, 2012 at 10:48 pm ET


Fukushima meltdowns’ March 2011 fallout higher than estimated, near 900,000 terabecquerels: Tepco
May 25, 2012


Some 4,600 terabecquerels of radioactive substances were discharged when an explosion ripped through the reactor 1 building March 12, and another 1,060 following an explosion at reactor 3 two days later, according to Tepco’s study of the fallout emitted by the plant’s three crippled units between March 12 and March 31.

The emissions peaked March 15 and 16, possibly because the primary containment vessels of the three reactors degraded due to high temperatures and released massive amounts of fallout and steam from their upper part.


Fukushima radiation release estimates are based upon the primary containment vessels (PCVs) staying intact and emitting only a tiny fraction of the overall radioactivity contained inside. For example:

Major Study: “We […] assumed a release fraction […] for the reactor cores [of] less than 1% of the caesium inventory”

More needs to be reported about the ‘degraded’ PCVs, as Tepco is now suggesting their condition had deteriorated to the point of releasing ‘massive amounts of fallout’ from the ‘upper part’.

If the tops were degraded enough to allow for massive radiation releases, what about the bottoms of the PCVs — where the corium is widely reported to be?

Here’s a representative example of how media reports describe the condition of the PCVs: BBC News – How does Fukushima differ from Chernobyl?

Fukushima: Japanese authorities stress that unlike at Chernobyl, the containment vessels at Fukushima remain intact.

Chernobyl: The reactor […] had no containment structure and nothing stopped the trajectory of radioactive materials into the air.

See also: [intlink id=”fairewinds-nuclear-expert-believes-top-lifted-off-reactor-no-1-containment-before-explosion-video” type=”post”]{{empty}}[/intlink]

Published: May 24th, 2012 at 10:48 pm ET


Related Posts

  1. TEPCO unable to verify water levels at reactors No. 2 and 3 — Suspects water is leaking from damaged containment vessels April 26, 2011
  2. TEPCO analysis indicates Reactor No. 1 and 2 have breached containment vessels meant to stop radiation from leaking May 25, 2011
  3. Japan Times: Much of melted fuel is believed to have burned down to bottom of containment vessels — At “last line of defense” January 20, 2012
  4. Japan Times: Melted fuel burned holes in Fukushima reactors — Explosions cracked containment vessels? March 8, 2013
  5. Japan Times on Melt Through: “Molten ‘lava’ melted bottom of containment vessel,” says nuclear engineer given access by top official — Huge amounts of fission materials released into environment April 18, 2012

20 comments to Tepco admits high temps may have degraded containment vessels after meltdowns — ‘Massive amounts of fallout’ released from upper part of reactors?

  • Sharp2197 Sharp2197

    Tepco is leaking more info. and it keeps getting worse.

  • Will tepco admit they are 'to-date' continuing to withhold sensitive and crucial data (in their possession) (which is a criminal omission); And by doing so are: Continuously putting human lives at risk of unknown radioactive exposure. More often than not above the legally recognized safety limits designed by the very nuclear entities responsible for admitting said repercussions and consequences to said healths…
    All the while:
    Limiting the public spectrum of trust and efficiency in containing said crisis, by postponing this very data.

    This making international bodies of governments, helpless to protect their own citizens. Which is essentially damning all said Potential progress of multinational support; Which could be making way: In the event they stopped Withholding this very data… By simply telling the FKN Truth…

    Ya, thats my 2 cents

  • CB CB

    I'm tired of revisiting the past. No matter how much you revisit the past…there's nothing new to see. I would like to move forward. We have covered this degradation of metals, Tepcos admission wouldn't be admissible in a court room.

    • Max1 Max1

      I disagree and here's why…
      … Those that die, die because of the past.

      1) Forget that and you might as well forget them, too.
      2) It's easier to hold people accountable for their crimes when we remember their crimes and what they did.
      3) Forgetting the past allows room to repeat the same mistakes.

      Each revelation is good to reveal. Each revelation sets sparks in a few more hearts and minds. Each revelation says louder and louder, "HEY, Mr. TEPCO. You're murderous operations MUST stop and Mr. TEPCO, DO. NOT. PASS. GO!"

      • CB CB

        I'm quick to forget just a very small percent of our population even knows whats happened and this maybe (new) news to some.
        ~ Degraded containment vessels, another factor that needs more attention. Is this like a metal fatigue?
        Is there math to this and a predictable date to metal failure under the loads the containment carries?

  • Sickputer

    From later in the JapanTimes article:

    "In the following months, however, the amount of radioactive substances spewed by the three reactors was less than 1 percent of the levels seen in March, Tepco's study showed."

    SP: Does anyone watching the webcams for 400+ days believe these Fuku liars? They must be insane.

    • Depends on if you were talking about the days is was too convected to even see the reactors themselves, The days the cameras were taken offline (so we couldn't see a thing)… or the days fire was clearly visible near the venting tower (top of the common fuel storage pool)…

  • TheBigPicture TheBigPicture

    Don't listen to biased and untruthful Tepco. The U.S. government is the guilty party here, and staying mums. They'd like nothing more than to make the little guy (tepco) be the focus of attention, but the U.S knows exactly what spewed, and what is spewing. They need to fess up, or loose their job. I won't vote for any weasel that stuck his head in the sand. Btw, who does that leave?

  • Jebus Jebus

    Umm, BOOM! BOOM! BOOM!

    Reactor 3 Nuclear Explosion at Fukushima Daiichi Nuclear Power Plant

    Leak! Leak! Leak!


    • jec jec

      Got to thank Nuckelchen for the great sleuthing. But doesnt look like any kind of COLD SHUTDOWN or Cold shutdown STATE (the new TEPCO definition to save face)..that anyone has EVER seen or heard of. Do you think these emissions are from a bubble bath? Mr. TEPCOman your legacy of death will follow you forever.

      • Jebus Jebus

        The only thing in "Cold Shutdown" at tepco.gov are their brains!

        • Max1 Max1

          hear, hear!

        • Sam Sam

          Would Dave Letterman wake up his brain from Cold Shutdown
          and do a top 10 lies of Fukushima. He could help break the
          wall of MSM silence. of course he would immediately be put out
          to pasture.

          • Max1 Max1

            He could have a TEPCO Rep come on and do it…
            … Then it gives the truth some air of make believe.

            The audience is conditioned for such plays…
            … It softens the blows of the truths.

            D.L.: "And No. 1…"
            TEPCO: "Everything is within limits."

  • Max1 Max1

    I see…
    … "Everything is within limits."

    Since when has TEPCO ever admitted too as much?

    • Jebus Jebus

      "Everything is within limits." and the sky's the limit…

      • Max1 Max1

        They've been saying that line from the get-go.
        "Everything is within limits."

        Each new revelation, "within limits" until they are forced to retract that statement by acknowledging closer to the truth when facts reveal themselves.

  • ion jean ion jean

    "Massive amounts of fallout and steam" OK so now we can safely assume that where there is Smoke there is Fire and where there is Steam there is Fallout; where there is Rain there is Strontium 90 (cause it fractionates and comes back down slowly) and where there is Food it is Radioactive…

    How long can we live without food?? We need at least 120 years.

    What do we do with a government that has miserably failed us? According to Jefferson, it is our DUTY to dissolve it!

  • PhilipUpNorth philipupnorth

    GE Mark I Containment Vessel cannot contain a meltdown. Pressure Relief Valves have been retrofitted to allow excess gas pressure to be released into the atmosphere. The Wet Well doughnut was added because Mark I Containment is too small. Fuku demonstrated that Mark I Containments actually contained nothing. There is little water or melted fuel left in Containments 1,2,&3. Coriums 1,2,&3 have exited through the bottom of Containments and Wet Wells, and are no longer to be found in Buildings 1,2,&3. GE Mark I reactors are one big design flaw, a major public safety hazzard, and must be shut down immediately.

  • Sharp2197 Sharp2197

    from a story just a few hours before this one.
    The Fukushima reactor, however, has so far released 360,000 TBq of cesium-137,
    Now this story says 900,000 TBq
    What will the next story say, they are easing us into the real number so that it won't be a shock.
    Expect the numbers to keep going up in increments, so as not to shock the public.