On May 5th, we heard that TEPCO had developed a plan to achieve cold shutdown of Reactor No. 1 at Fukushima Daiichi, and was about to begin it. Workers were scheduled to enter the reactor building. Tragically, that plan has now had to be abandoned.
It was never really a sure thing. Even the first step of the plan (flood the containment surrounding the reactor with water, to try to cover the reactor core, which was already thought to be partially melted, with water) was iffy. There was no way to tell whether the containment would leak or not when filled with water.
The reasoning for the plan was basically that there are no good options left. Here is a sketch and discussion of the plan laid out prior to commencing:
NEI magazine reports that the nuclear regulator NISA gave the reasoning for the go-ahead as follows: “under the circumstances, ‘NISA has evaluated the measures as appropriate since there was no other effective option.’ ” (emphasis added)
Now we know that the containment does leak, way too much, and that the plan has to be abandoned: http://www.asahi.com/english/TKY201105150169.html
But if there is no other effective option, where do things stand now?
I see that Arnie Gundersen of Fairewinds has been ahead of the curve in reporting events at Fukushima. He has a series of video updates on Fukushima on the company’s website; his informative summary-style video report of last week (May 13, 2011) is here:
“Fukushima: One Step Forward and Four Steps Back as Each Unit Challenged by New Problems” http://www.fairewinds.com/updates
“There is no other effective option.” And now the only effective option can’t proceed.
As I said in earlier posts, I don’t know what to say.