The immediate threat at Fukushima-Daiichi nuclear plant remains the possibility of damage to spent fuel in the spent fuel pools at all six reactor units, the Japan Atomic Industrial Forum (JAIF) said.
(06:00 central European time) on 19 March using police high-pressure water cannon and Japanese Self-Defence Force fire engines. US Army fire engines were also used, according to JAIF.
These efforts had been continuing for seven hours at the time of the last update issued by JAIF. Workers were preparing to fill the spent fuel pool at unit 4, JAIF said.
Efforts are under way to restore an external power supply to the plant. JAIF said the supply was scheduled be connected to units 1 and 2 today (19 March Japan time). Units 3 to 6 are scheduled to be connected on 20 March.
The IAEA said it was not known if the water pumps have been damaged and if they will work when power is restored.
Fuel Integrity in Spent Fuel Pools
Unit 1: Water injection is being considered.
Unit 2: No information.
Unit 3: Water level low, water injection continues.
Unit 4: Water level low, preparing water injection.
Unit 5: Pool temperature high, but decreasing.
Unit 6: Pool temperature increasing.
At unit 3, efforts to fill the spent fuel pool with water began at 14:00 Japan time
Common spent fuel pool: secure water level and a slow rise in temperature, according to Tepco.
The IAEA said it lacked reliable, validated data on water levels and temperatures at the spent fuel pools at units 3 and 4. The agency said temperatures at the spent fuel pools in units 5 and 6 had risen in the past few days, but this does not give rise to immediate concern. Water continues to be circulated within the reactor pressure vessels and the spent fuel ponds at both units.
Units 1, 2 and 3: Injecting seawater continues. Core and fuel integrity damaged, reactor pressure vessel integrity “unknown”
Unit 4: Already shut down when the quake struck. Building integrity severely damaged.
Unit 5: Already shut down when the quake struck. Sufficient level of reactor coolant to ensure safety is maintained and operation of one of the diesel generators has been re-established. Venting not necessary.
Unit 6: Already shut down when the quake struck. Sufficient level of reactor coolant to ensure safety is maintained and operation of a second diesel generator has been re-established. Venting not necessary.