Thursday, December 19, 2013

Fukushima cores melted down

The reactor cores of Fukushima Daiichi 1-3 suffered a catastrophic meltdown.  TEPCO has been denying this since the original disaster.  No one I knew believed them. Last Friday they finally came clean.

The only good news is that core meltdowns do not trigger the "China Syndrome."  The rest of the news is just terrible.  And as nearly as I can tell, no one has any idea of what to do next.  The Japanese government has asked for international help.  No one has stepped forward.

Fukushima Core Meltdown: TEPCO Confirms Systemic Cooling System Failures

by GreyRaven | December 15, 2013

An article published by Asahi Shimbun addressing a TEPCO report released on December 13. 2013 describes the desperate measures taken at Fukushima Daiichi Units 1, 2 and 3 in the immediate aftermath of the March 2011 earthquake in order to avoid the core meltdowns of these reactors.

As has now been confirmed, very little of their cooling water ever reached the reactor cores, then in the process of rapidly melting down.

Quote: Asahi Shimbun

“Fire engines were used in a desperate, and ultimately futile, attempt to pump water to cool overheating reactors during the early phase of the 2011 Fukushima No. 1 nuclear power plant disaster, Tokyo Electric Power Co. said.

According to a Dec. 13 report by the operator of the crippled facility, water was pumped in sufficient quantity to avert core meltdowns in the No. 1, No. 2 and No. 3 reactors, but much of it strayed into irrelevant pipes and ended up elsewhere.”

The article goes on to state:

“TEPCO said more than seven times the requisite volume of cooling water was pumped into the No. 2 reactor. But the water failed to cool it and the other reactors efficiently, and could not stop the core meltdowns in the No. 1, No. 2 and No. 3 reactors.

An examination of pipe diagrams and related equipment showed the pipes to the reactors had branches leading off to other areas and devices, such as condensation storage tanks. TEPCO concluded that too much of the pumped-in water leaked into those branches and never reached the reactors.

TEPCO officials said they knew as early as late March 2011 about those leakage routes.”

The December 13. TEPCO report includes this singular admission:

"We should have shared the finding with the public in the belief it would help promote universal safety, but failed to do so," said TEPCO Managing Executive Officer Takafumi Anegawa.”

The previous lack of forthrightness on TEPCO’s part on this issue has serious consequences.

Whereas all evaluations made to date regarding what actually occurred to the nuclear cores of Units 1, 2 and 3 were based on the information released by TEPCO that sufficient amounts of water had been pumped into the cores, in order to prevent or at least reduce the meltdowns, it now turns out that very little of that water, pumped at great risk to the lives of the fire crews on the site, actually reached those cores and that this failure occurred due to design flaws in the piping system, which led directly to the complete failure of all further attempts to cool the melting cores.

As effective cooling measures were technically obstructed during and after the meltdowns, it must now be presumed that the magnitude and severity of each of the core meltdowns is much greater than originally assumed.

Taking Unit 2 as an example, according to TEPCO “more than seven times the requisite volume of cooling water was pumped into the No. 2 reactor. But the water failed to cool it…”. As usual, TEPCO fails to add a time frame for when this took place, but from the wording one can assume that this occurred in the immediate aftermath of that reactor’s failure. This also coincides with information contained in the the graphic representation of Unit 2 temperatures.

According to those measurements even the sevenfold amount of water being pumped in in March apparently had no marked effect on the overall temperature level. It is now abundantly clear why this was so. It is also apparent that the firstsignificant reduction in temperature took place months later on 14. And 16. September 2011 when an “Adjustment of Water Rate” and an “Increased Water Injection Rate” were finally initialized. Presumably that was when TEPCO managed to get a cooling system working again.

From the sudden and clearly visible drop in temperature after this time it becomes evident that little or no cooling took place from the time of the meltdown until the middle of September. Unit 3 demonstrated a similar temperature drop at around the same time when comparable water rate adjustments were undertaken.

The full implications are horrific.

One can only conclude that a huge percentage of all the water pumped into the cores of Unit 1, 2 and 3 between March 2011 and September 2011 never reached its intended goal nor served the purpose of cooling the what remained of the cores.

It appears that for nearly six months after the meltdowns no effective cooling of the core-remains and/or escaped corium lava within these units occurred and that this was initialized, adequately and with perceivable effect, only sometime in September 2011!

TEPCO admittedly knew this from March 2011 onward.

And lied.

Link to The Asahi Shimbun article:
See also: SimplyInfo article "TEPCO Admits Water Injection Failure, Has Known Since March 2011"


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