.On Sunday, 15 May 2011, the Tokyo Electric Power Company (TEPCO) announced that during the initial incident on 11 March, the core of Fukushima No. 1 reactor reached 2800 degrees Celsius, and completely melted down falling into the bottom of the reactor pressure vessel (RPV), forming a large pool of liquid uranium and other substances there. The molten fuel (aka "corium") caused holes or cracks to form in the RPV resulting in a loss of pressure and leakage of water into the secondary containment. This containment is apparently also cracked or punctured, since the 8 tons of water per hour they are currently injecting are showing up in the reactor basement. They plan to up the injection to 10 tons per hour to try to keep the fuel cooler so that it will not keep destroying the concrete and progressing down toward bedrock (china syndrome). Unfortunately, the bedrock is "mudstone", a mixture of loose shales, sand, and ground water, which will not provide a barrier to further dispersion of the corium into the aquifer.
I wonder when will will hear about the condition of Fukushima Nos. 2 and 3. I suspect they are just as bad.
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