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Tuesday, March 29, 2011

NISA Briefing Notes

Here are some notes from the latest NISA (Nuclear & Industrial Safety Agency) briefing, given the morning of the 29th (Tokyo time.)

No. 1 reactor continued to show an increase in temperature after a decrease in cooling water flow was made; the idea is to provide the proper amount of cooling while not over-using water. Since the temperature was increasing, the flow rate of injection water to the core was increased from the previous 113 liters/min to 140 liters/min. The temperature continued to rise for a short while, but seemed to have leveled off at the time of the briefing. Hoped to get the temporary fresh water pump and diesel generator working today. Had hoped to use a concrete truck with long arm to spray the spent fuel pool but the truck has experienced a failure and may not be repaired until the 31st. As a result, the pool has lost a little water and heated up a little but the situation is not serious. DC electric system work continues. Three pumps working to move water from basement into condenser; water level in basement not going down very quickly.

No. 2 plant changed to freshwater injection with the new setup days ago, and hopefully today will begin using fresh water on the spent fuel pool. Water relocation effort underway to clear condenser to get turbine building water into it.

No. 3 plant had the new temporary electric pump setup put on line 8:30 yesterday, using fresh water. Electric work continues, focused on 125V DC today.

No. 4: Nothing of note.

Trenches outside plant will be monitored every 12 hours. The drains for the trench at No. 1 plant have been buried to prevent any water exiting, but this hasn't been deemed necessary at the other plants yet.

THIS WAS THE DATA given during the last brief. A check of the last available temperature data shows a feed nozzle temperature of about 304C on No. 1 plant, which is way back up where it was about a week ago, echoing the NISA statement.

9:30 AM Eastern Tuesday 3/29

1 comment:

  1. Again, update much appreciated.

    Doesn't a whole lot of planning depend on determining the water outflow rate at these plants?