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Corporate Information

 
Press Release (May 02,2011)
Amendment of the report regarding emergency countermeasures for safety at Kashiwazaki Kariwa Nuclear Power Station
In light of the situation concerning the damages at Fukushima Daiichi 
Nuclear Power Station due to the Tohoku-Chihou-Taiheiyou-Oki Earthquake 
that occurred on March 11th 2011, TEPCO has begun implementing emergency 
countermeasures to prevent damages to the reactor core and spent fuel, 
suppress discharges of radioactive materials and restore the cooling 
function of the reactor facility. This is all being done under the 
assumption that all three functions (Availability of all facilities that 
supply AC power, reactor cooling by seawater, and spent fuel pool cooling) 
were simultaneously failed when the tsunami struck.

We received an Order(*) from the Minister of Economy, Trade and Industry 
that requires the enforcement of emergency countermeasures for further 
safety at the Nuclear Power Station. Based on this, in addition to 
emergency safety countermeasures at Kashiwazaki Kariwa, we organized a 
report regarding the prevention of flooding by tsunamis, and further 
countermeasure plans to restore safety which was submitted to the Ministry 
of Economy, Trade and Industry (METI) on April 21st, 2011.
                                            (Announced on 21st April 2011)

After the submission of the report, some errors were pointed out to us by 
the Nuclear and Industrial Safety Agency (NISA). In response, we amended 
the errors and re-submitted the report to the Minister of Economy, Trade 
and Industry today.

<Amended part>
Emergency countermeasures for safety at Kashiwazaki Kariwa Nuclear Power 
Station (implementation report)
The data of the maximum load and others in Units 6 and 7 in "Attachment 4-
(3) 1. a. Function of Alternative Water Injection to Reactors and Spent 
Fuel Pools" have been amended. (Please see attachments for details)

We seek the continuous cooperation and support from the ministries and 
local communities, and via tight communication, we intend to focus all of 
our efforts towards the stabilization of Fukushima Daiichi Nuclear Power 
Station.

If we identify any points that should be reflected into the Tsunami 
countermeasures at Kashiwazaki Kariwa Nuclear Power Station during the 
process of analysis and evaluation of the cause(s) of the accident, we 
will take swift action to have them incorporated.

Attachment 1: Attachment 4-(3)
  1. a. Function of Alternative Water Injection to Reactors and Spent Fuel 
  Pools (after revision) (PDF 14.3KB)
Attachment 2: Attachment 4-(3)
  1. a. Function of Alternative Water Injection to Reactors and Spent Fuel 
  Pools (before revision) (PDF 14.1KB)

*Order:
"Implementation of emergency safety measures of other nuclear power 
stations based on the accidents at Fukushima Daiichi & Fukushima Daini 
Nuclear Power Stations (Order)"
                                            (NISA no.7 on March 28, 2011)

The accident at Fukushima Daiichi Nuclear Power Station caused by the 
tsunami that struck immediately following the Tohoku-Chihou-Taiheiyou-Oki 
Earthquake resulted in a nuclear disaster of unprecedented portions in 
Japan. Currently, TEPCO and relevant authorities such as national and local 
governments have come together to prevent the outspread of this nuclear 
disaster and repair the damages. 
NISA has garnered all of its resources to continuously tackle the many 
challenges this accident is posing and through analysis and evaluation is 
working to gain a thorough and overall understanding of the many factors 
that comprise the accident including the generating mechanism of the 
tsunami. The causes of the accident will be clarified and drastic measures 
will be taken.
On the other hand, it would appear that large tsunamis of this scale 
triggered by huge earthquakes like the one that struck on March 11th do 
not occur frequently, but may cause a serious damage to a nuclear power 
station. In consideration of this matter, as a start and based on currently 
understood factors, emergency safety measures that will enable the 
suppression of the discharge of radioactive materials and the restoration 
of the reactor facility's cooling function in the event that the power 
supply function is failed due to a tsunami should be taken for those 
nuclear power stations besides Fukushima Daiichi Nuclear Power Station and 
Fukushima Daini Nuclear Power Station. Furthermore, NISA must confirm via 
examinations etcetera that the creation and implementation of these 
emergency safety measures are conducted appropriately by the electric 
power suppliers.  If this is done, then we should be able to prevent 
reactor damages leading to the occurrence of a nuclear disaster in the 
event that the power supply function is failed by a tsunami.
Therefore, according to the regulations on operation maintenance for 
operation systems for the maintenance of a reactor facility in the event 
of a tsunami and the installation of an actual generation reactor after 
revision which requires the maintenance of security regulations and 
operation regulations, we request immediate permission to work on the 
following emergency safety measures and report the implementation status 
of these emergency safety measures. 

Notes:
For emergency safety measures, the following countermeasures to prevent a 
damage to the reactor core and spent fuel, suppress discharge of 
radioactive materials and restore the cooling function of the reactor 
facility should be taken even if the three functions such as the functions 
of all facilities that supply AC power, the functions of all facilities 
that cool the reactor facility and the function of all facilities that 
cool the spent fuel pool by seawater are failed by the tsunami. 
Furthermore, security regulation should be maintained according to the 
revision of the regulations concerning installation of the actual 
generation reactor and operations, and the approval of the revision of 
the security regulations should be applied.

1. Implementation of emergency inspection
 Implementation of an emergency inspection of equipment and facilities to 
 prepare for an emergency response in the event of a tsunami
2. Implementation of the review and training of the emergency response plan
 Implementation of the review and training of an emergency response plan 
 that assumes that the functions of all facilities that supply AC power, 
 the functions of all facilities that cool the reactor facility and the 
 functions of all facilities that cool the spent fuel pool by seawater 
 have been failed.
3. Securing of power source in emergency situations
 Securing of a backup power source which can supply necessary power agilely 
 in case any power sources in the nuclear power station are lost and 
 alternate emergency power sources cannot be secured
4. Securing of a definitive heat removal function in emergency situations
 Preparation of restoration countermeasures of an agile heat removal 
 function that assumes loss of the seawater system facility or its function
5. Securing the cooling of the spent fuel pool in emergency situations
 Implementation of countermeasures to supply cooling water agilely in case 
 the cooling of spent fuel pool and normal water supply to the spent fuel 
 pool in the nuclear power station inadvertently stop.
6. Implementation of immediate countermeasures taken in consideration of 
   the configuration of each nuclear power station


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