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Thursday, March 24, 2011

First update of the 25th (Tokyo date)

It is now the morning of the 25th of March in Japan, and the first technical updates are available before the briefings today -- which as always we'll be watching and then reporting on.

At this moment, only a bit of vapor is visible above the plants at Fukushima Daiichi, and no smoke.

On the 24th, TEPCO put 120 tons of seawater into the spent fuel pool of No. 1 plant.

No. 4 plant had 150 tons of seawater sprayed onto the spent fuel pool by the long-armed concrete pouring vehicle which has made much press in many areas. A number of pictures, which this writer feels will become iconic, have been made of this vehicle in operation beside the blown apart No. 4 plant reactor building.

The seawater pump for RHR at No. 5 plant is back on line, and operating now.. the system was back on at about 4:30 PM local Tokyo time.

Feedwater inlet nozzle and reactor vessel lower head temps continue to lower on all three plants with cores installed. Apparently TEPCO doesn't think the readings on feed nozzle temp on No. 3 plant are right (they've been widely disparate) and now the reading for this value on this plant is listed on two different documents as "Under Survey." It is probably the most curious of all the readings -- the very wide temperature disparity on this reactor alone.

Control room for No. 1 plant has lights.

Still no data on what I&C is energized if any.


The latest JAIF status update available wasn't that exciting in terms of differences, but we'll link it here to provide complete continuity.

Expect a lot more when the briefings begin. We're hoping to start to hear some bigger picture information about these plants soon as we begin to examine when we will see the end of the Accident Management / Accident Mitigation phase and enter the Cleanup phase. Particularly of interest to me is the fact that most prolonged station blackout fault analyses indicate significant core melt and probable reactor vessel failure, and even containment failure. One wonders what the exact status of the reactor cores is.. and given the vast hydrogen release, the release of fission products on a wide scale, and the high radiation areas it's likely that core damage in all three plants is very severe.

6:30 PM Eastern Thursday 3/24

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