APR: your source for nuclear news and analysis since April 16, 2010

Tuesday, March 22, 2011

When will this be over? Fukushima Daiichi....

I've mentioned this before on this site, and now there are some statements by various IAEA officials and Japanese government officials about "light at the end of the tunnel" and "cautiously optimistic about the situation improving" and so on.

Let me clear up a few things about the situation at Fukushima Daiichi.

1. Things are not "getting better." They simply are not getting any worse; the "accident response / accident mitigation" phase is still in progress. The amount of core damage remains either the same or is very slowly worsening. The amount of damage to, and release from, the spent fuel pools is remaining about the same it appears or very infrequently occurring again. Contamination on the ground is there, decaying according to its half life for any given element and it's in the water as well.

2. We need to be clear about what the ACCIDENT PHASE is and when it's over. We can say that the accident sequence will be over when the installed reactor cores are being cooled and monitored and no further damage is occurring to the fuel elements and no further releases of fission products to the atmosphere or environment are likely. The end of the accident phase will also be contingent essentially upon the same condition for the spent fuel pools. In terms of the number of locations of fuel damage (three installed reactors, probably three spent fuel pools) concurrently this accident certainly sets a new standard. This will probably occur within the next week, although it's hard to say.

3. As discussed in some detail earlier on this blog (if you didn't read it, please go back and do so) the eventual cleanup of the site depends on a decision that could take a number of paths depending upon what is found when the actual inspections of the reactor buildings are completed. This inspection might depend upon demolition of the upper area and total removal of all spent fuel to some other area on site. One would expect this step to take months.

4. Today we will show on this blog some of the long term options for the site including best case and worst case. Naturally the best case scenario for TEPCO at the Fukushima Daiichi site would be to completely remove plants No. 1 through No. 4 and clear that land for any future use, put plants No. 5 and No. 6 back on line and then build the already planned plants No. 7 and No. 8 at the site and get them on the grid to help replace the generating capacity they'll lose from the four plants removed. This scenario is very unlikely, frankly... although by no means impossible given what we know now.

This might help clear up the confusion starting from the flurry of press briefings and releases that are starting to appear-- particularly the Japanese briefings now being daily given to foreign media, whose questions, at least in terms of the American media, are sure to be inane, probably incendiary and likely pointless.

7:00 AM Eastern Tuesday 3/22

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