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Sunday, March 27, 2011

NISA update, morning of 3/28 in Japan

It's the morning of the 28th in Japan, and NISA (Nuclear and Industrial Safety Agency) has just given another briefing. The able Hidehiko Nishiyama, always the morning briefing point man for NISA, gave the particulars. We were hoping to stall long enough to get the copy of the documents that accompany this briefing, but they're not available yet so in order to remain timely we'll run what we have... which in all likelihood won't be contradicted by anything in the briefing papers.

We still read them anyway.

Details given this morning: In general, applicable to all three reactor plants which were at power when the quake hit; all will eventually be changed from having fresh water injected to the cores by fire trucks (pumper trucks) as they are now to electric pumps. The fire trucks need to be refueled fairly often, and this arrangement is not necessarily the best. Electric pumps for each plant will be placed in a temporary arrangement, powered by diesel generators. To ensure total separation of the plants, and any event at any one plant, every plant will have its own dedicated portable diesel generator and fresh water pump.

In terms of specific plants, it was deemed a top priority to achieve this setup on No. 2 plant first and this was done at 6:30 PM Tokyo time on the 27th. This plant is still being injected with fresh water containing boric acid. (Nishiyama's exact words were "we're injecting fresh water and we need boric acid on this plant" or something like that.)

Now, to plant specific details and analysis...

No. 1 plant's reactor pressure vessel temperatures are rising again, and fresh water injection rate will be adjusted upward to correct for this. (Last time I saw a new number the feed nozzle temperature was about 204C.) This plant should get its electric water pump and diesel generator on the 29th. TEPCO has added two more fire pumps to the one working the turbine building basement water pool which has developed in order to get this contaminated water into the condenser hotwell.

At No. 2 and No. 3 plants, the condenser hotwells are already full or very nearly so and this water -- which isn't contaminated so far as we know now -- might be simply pumped outside or to sea in order to get the hotwells empty to make room for the water in the basements. Nishiyama's remarks, though, leave some opening as to the plan for No. 3 plant since he indicated they're still deciding what to do with that water.

The cyclical nature of watering the various spent fuel pools, now using the concrete pumper truck and various 'water cannon' vehicles continues as needed, albeit with fresh water now.

We'll be looking for the NISA and TEPCO documents to appear fairly soon, and likely some JAIF status charts a bit later.

3/27 Eastern Sunday March 27

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