TEPCO-owned nuclear power plant Fukushima Daiichi suffered a temporary power outage last night and at the time of reporting of 19 March 6.30am, the cooling system of the spent fuel pools that were stopped have not been restored. According to TEPCO, it is taking a long time to determine the cause, and as such the cooling systems have remained halted.
The trouble occurred at around 7pm on the 18th. According to TEPCO and the Nuclear Regulatory Agency, in addition to the spent fuel pools of Unit 1, 3 and 4, the units' shared cooling system for the pools are also stopped. For Unit 4's pool which has the highest water temperature, it is estimated there is about 4 days' allowance before it reaches 65 degrees which is the maximum under TEPCO's safety standards. There is no abnormality in the water coolant injection for the reactors and the monitoring post that measures surrounding radiation levels had no changes in value.
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(Translated by OP.)
Hope they can restore it safely and soon. Judging from Twitter, Japanese people are feeling uneasy about the situation.