On March 11 2011, Fukushima Daini Nuclear Power Station Units 1 to 4
(Boiling Water Reactors, rated output 1,100 Megawatts each) that we had
been operating at rated thermal output shutdown automatically at 2:48 pm,
due to the Tohoku-Chihou-Taiheiyou-Oki Earthquake (previously announced
on March 11).
At 7:15 pm on March 15, the reactor of Unit 4 achieved a cold shutdown. As
a result, all the Units of Fukushima Daini Nuclear Power Station achieved
the status of cold shutdown (previously announced on March 15).
As of 3:00 pm on July 7, the Units 1 to 4 remain in a cold shutdown (please
refer to the appendix).
< Updates are underlined >
At 2:05 pm on July 7, a labor found a spark in the breaker of power panel
while a labor investigated the power panel in the first floor of basement
of reactor building of Unit 1. At 2:30 pm on July 7, TEPCO workers confirmed.
Afterwards, we will open the connecting breaker that supplies electricity
to the breaker and investigate the cause of a spark.
Due to the investigation, we will stop residual heat removal system (B) and
continue to operation to manage the temperature of reactor building and
spent fuel pool.
We will make our best efforts to stabilize each plant.
Appendix: TEPCO Plant Status of Fukushima Daini Nuclear Power Station