19 Mars 2013
March 20, 2013
Cooling restored at all Fukushima fuel pools
[what about the radioactive water decontamination system ?]
Tokyo Electric Power Company says it has restored all 4 cooling systems for the spent fuel pools at the Fukushima Daiichi nuclear plant. They had stopped working on Monday afternoon, raising concerns about a rise in the cooling water's temperature.
A power failure suspended the cooling systems for the spent fuel pools of the No. 1, 3 and 4 reactors as well as a shared pool in the plant's compound.
TEPCO repaired the cooling systems step by step.
The utility says it finished repairing the one for a shared pool early Wednesday morning. The shared pool contains the largest number of spent fuel rods that need to be cooled down constantly.
TEPCO officials said 3 power distribution boards had stopped working, leading to the halt of the cooling systems. The boards were using electricity from outside the plant.
The firm continues to investigate what caused the boards to stop functioning.
TEPCO says the temperature of the No. 4 pool was the highest among the 4 pools, and was 25 degrees Celsius one hour before the power failure on Monday.[and 31, 6° at 1 pm Tuesday]
The temperature rose above 30 degrees Celsius at 4:30 PM on Tuesday. TEPCO said this level will not affect cooling, as it is below the safety threshold of 65 degrees.
The firm says the power failure did not affect the water injection to the No. 1, 2 and 3 reactors. The reactors suffered core meltdowns in the early days of the nuclear crisis triggered by the March 2011 quake and tsunami.
The utility also says no change has been observed in radiation levels at monitoring posts around the plant.
Mar. 19, 2013 - Updated 15:55 UTC (00:55 JST)