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Friday, May 27, 2011

Fukushima Daiichi Update: Friday 5/27

There is not a lot of news coming out of Fukushima Daiichi at the moment, at least of any emergent nature.

Probably the most important news is that there is a water loss occurring from the waste treatment buildings into which contaminated water was being pumped from the reactor plant turbine buildings. TEPCO has identified some leak points, and where they'll try to stop leakage. TEPCO's illustration below, which is an overhead view, is fully self-explanatory. Click to enlarge.

Meanwhile, in plant-related news the injection rate at No. 3 plant is now adjusted to 2 cubic meters per hour through the fire extinguishing line and about 13.5 cubic meters per hour through the feed line. Temperatures are steady. Reportedly, TEPCO is beginning work at No. 2 plant to change the injection path for No. 2 over to the feed system from the fire extinguishing system. (Unit 1 is on the feed line, Unit 2 is on the fire extinguishing line, and Unit 3 is on both lines as noted.)

TEPCO sampled the air above the reactor buildings on the 24th using equipment held over the buildings by concrete pumper truck arms. Below, one of the trucks holding the sensor over No. 1 reactor building in a TEPCO press release photo.

Below, another truck samples the air over the No. 4 reactor building in another TEPCO press release photo.

The IAEA has sent an inspection team to Fukushima Daiichi; the team toured practically the entire site, and will make a report to TEPCO on or about June 1st regarding its findings. Below, the group approaches No. 3 (left) and No. 4 (right) reactor buildings on the hillside that is immediately west of these structures. This photo blows up very large when clicked, but is worth seeing in full size and in high resolution.

Since we're updating a number of illustrations... We've talked about decay heat removal many many times on this blog, and talked about the need to remove heat for a long time after the reactors are shut down. (Long-term readers might remember my quote about how much heat the metal in a decommissioned US Navy submarine power plant gives off due to its irradiation.... THAT is how seriously we've covered decay heat on this blog.) Since we've been so thorough to this end on this blog, we'll finally show a new graph released as a press handout by TEPCO showing the decay heat output curves for plants No. 1, 2 and 3 at Fukushima Daiichi, seen below. This will give a good idea for readers who are new to this blog of how much heat even a shut down core is liberating long after shutdown.

8:40 PM Eastern Friday 5/27


  1. Maybe wistful thinking, but if the core elements keep belting out that much latent heat long after shutdown, why not just continue generating steam with it even after shutdown till the last therm unit is milked from it? Wouldn't it even be in a sense a "safer" situation since you're not dealing with an active reactor running at full bore? Is it more of an irradiated materials (vessel, pumps, etc) strength/integrity limiting longevity issue? (I mean, technically how long can you push a sub with its original reactor?) I'm no engineer, just wondering. Also, I'm not being flippant, but has TEPCO ever thought of enlisting the aid of those "ASIMO" android robots to go and do what the cute crawlers can't?

    James Greenidge

  2. Hi Will!

    Do you have any ideas why TEPCO did anonymize some of the names written on the overalls of the visitors? It's strange, some are clearly readable and other are 'whitened' out.