On March 11 2011, turbines and reactors of Fukushima Daini Nuclear Power
Station Units 1 to 4 (Boiling Water Reactors, rated output 1,100 Megawatts)
that we had been constantly operating at rated thermal output were
automatically shut down at 2:48 pm due to the Tohoku-Chihou-Taiheiyou-Oki
Earthquake (previously announced on March 11).
At 7:15 am on March 15, the reactor of Unit 4 achieved cold shutdown. As a
result, all reactors of Units 1 to 4 at Fukushima Daini Nuclear Power
Station achieved cold shutdown (previously announced on March 15).
As of 3:00 pm on August 29, the reactors of Unit 1 to 4 are in cold
shutdown (please refer to the appendix). We will continue to make our
endeavors to further stabilize each plant of cold shutdown.
<Underlined are new matters>
○Investigation of reactor containment vessel of unit 4 and inside
facilities
At 10:15 am on 29th August, in order to investigate soundness of
reactor containment vessel of unit 4 and inside facilities, we have
opened airlock for site workers (hatch to enter into the primary
containment vessel), and we started investigation.
We are planning the same investigation of Unit 1 to 3.
○Poor physical condition of a site worker of co-operating company
On 29th August, in the heater building*1 of unit 4, condition of a
site worker of co-operating company who was in charge of rerouting of
temporary cable was getting worse, at around 10:50 am, and as heat
stroke was anticipated, we treated drip infusion and at 11:26 am
transferred to J-village by our ambulance.
At 11:58 am, patient was transferred to Iwaki Kyoritu Hospital by
ambulance.
It is under medical treatment in the hospital.
No radioactive material attached to the body was found.
*1 Heat exchanger building
The building in which the heat exchanger is installed. The heat
exchanger is the facility for carrying out heat exchange of the
cooling water of the facility used in reactor containment vessel,
turbine building and centralized waste treatment facility. (Non-
Controlled Area)
Appendix: TEPCO Plant Status of Fukushima Daini Nuclear Power Station
(PDF 15.4KB)