(Mainichi Daily News) June 21, 2011
Preventing radiation contamination more important than TEPCO's stock prices
by Takao Yamada
Assistant Professor Hiroaki Koide, Kyoto University Research Reactor Institute:
As far as I can tell from the announcements made by Tokyo Electric Power Co. (TEPCO), the nuclear fuel that has melted down inside reactors at the Fukushima nuclear plant has gone through the bottom of the containers, which are like pressure cookers, and is lying on the concrete foundations, sinking into the ground below. We have to install a barrier deep in the soil and build a subterranean dam as soon as possible to prevent groundwater contaminated with radioactive materials from leaking into the ocean.
(my emphasis)
Estimates are on the order of $1B dollars to construct a subterranean dam -- that much money would destroy TEPCO and there is no reason to believe the Japanese government would pay for it. (Political realities aside, there is no choice -- it has to be done.)
So TEPCO's prepared answer to the obvious question, why hasn't this construction already started?
Underground water flows at a speed of about 5 to 10 centimeters a day, so we have more than a year before it reaches the shore.
The linked article (in both English and Japanese) goes on to speculate that the reason the Japanese government is so slow to react, just as with the end of WWII -- "common sense was lost, and the government was slow to reach a decision."
And there you have it. TEPCO wishes to make the Japanese government foot the bill, and the Japanese government reacts at the speed of frozen sludge moving uphill in winter. (IMHO)
But the key point in the article is that should such a dam be announced after June 28, it will confirm what is already strongly suspected, that one or more cores are presently resting on concrete below their containers and are eating their way down to the water table.