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Corporate Information

 
Press Release (Jul 07,2011)
Submission of the report to NISA regarding security of offsite power supply of Fukushima Daini Nuclear Power Station
 
On April 15, 2011, we received an instruction document entitled "Offsite 
power supply security of nuclear power stations and reprocessing plants"* 
from Nuclear and Industrial Safety Agency of Ministry of Economy, Trade and 
Industry (NISA). Afterward, pursuant to the document, we checked the status 
of implementation of measures to secure the offsite power supply and 
informed NISA on May 16. 
                        (Previously announced on April 15 and May 16, 2011)

On June 7, 2011, NISA informed us that the said report was evaluated as 
valid. In addition, we also received an instruction document from NISA to 
report the status of implementation of measurements to secure the offsite 
power supply of Fukushima Daini Nuclear Power Station, considering the 
status of the equipment restoration there and implementation of emergency 
safety measurements to keep the cold shutdown of the reactors. 
(Previously announced on June 7, 2011)

Afterwards, we checked the status of implementation of measures to secure 
the offsite power supply of Fukushima Daini Nuclear Power Station, and 
hereby announce to submit the report to NISA today. 

○Attachment
 Security of offsite power supply of Fukushima Daini Nuclear Power Station 
                                                              (PDF 77.1KB) 

                                                                       END

*Instruction document
"Offsite power supply security of nuclear power stations and reprocessing 
plants (directive)" (April 15th, 2011, NISA No.3)

There was a large blackout within the service area of Tohoku Electric Power 
Company due to Miyagiken-oki Earthquake on April 7, 2011.
This accident cast uncertainty about the reliability of power systems, 
since it starting from a grounding fault in one part of the power systems 
led to the cut of offsite power supply systems to nuclear power stations 
and reprocessing facilities (collectively "nuclear power stations etc."). 
Therefore, Nuclear and Industrial Safety Agency (NISA) instructs general 
electricity utilities to conduct the items stated below (only 1 and 4 are 
applicable to processing facilities). NISA also orders them to report the 
implementation status by May 16, 2011.

1.Considering that outage in power supply due to earthquake etc. could 
  affect offsite power supply to nuclear power stations etc., analyze and 
  evaluate the reliability of power supply in your company's power systems 
  which could affect power supply to nuclear power stations etc, and 
  consider measures to improve the reliability further of power supply to 
  such nuclear power stations (including enforcement of on site power in 
  nuclear power stations etc.). As for processing facilities, consider 
  improving equipment within such facilities which corresponds to the 
  measures above concerning the reliability of power systems which supplies 
  power to such facilities.

2.In order to improve the reliability of power supply to each unit in your 
  nuclear power stations, connect all the transmission lines which are 
  connected to multiple power lines to each unit and enable power supply.

3.Concerning power line towers of your nuclear power stations, evaluate 
  seismic adequacy, stabilities of foundation against earthquakes and 
  depending on the result conduct necessary countermeasures such as 
  reinforcement work.

4.Concerning electrical facilities such as switchyards of your nuclear 
  power stations etc., conduct countermeasures such as installing them 
  indoors and making them watertight to exclude impacts on tsunami. 
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