Concerning Measures to Respond to Severe Accidents at Hamaoka Nuclear Power Station(Report Concerning Direction of Minister of Economy, Trade and Industry)

This is to announce that Chubu Electric Power, following the instructions of the Minister of Economy, Trade and Industry,* submitted a report to the Nuclear and Industrial Safety Agency today concerning severe accident response measures to be taken immediately. These were among severe accident response measures listed in a Japanese national government report on the accident at the Fukushima Daiichi Nuclear Power Station of the Tokyo Electric Power Co., Inc.

The report will hereafter undergo a check and evaluation by the Nuclear and Industrial Safety Agency.

 

1. Instructions from Minister of Economy, Trade and Industry (Overview)

The work to recover from the 2011 accident at Fukushima Daiichi Nuclear Power Station revealed a number of issues concerning severe accident response. Based on these, select measures to take to respond quickly in the event of a severe accident (such as major damage to a reactor core). Of these, take the following measures that require immediate action and report their status by June 14, 2011.

(1) Secure the work environment in the central control room

Take measures so that in the event of complete loss of AC power, emergency ventilation and air conditioning equipment in the central control room can operate with a supply of power from power-supply cars.

(2) Secure means of communication within power station during emergencies

To ensure that work within the power station proceeds smoothly, take measures to secure dependable means of communication within the power station even if all AC power is lost.

(3) Secure equipment such as radiation suits, and prepare systems to control radiation

To ensure that workers are protected from radiation and radiation is controlled, take measures to secure equipment such as radiation suits and personal dosimeters (including such equipment that can be used interchangeably between businesses) and prepare systems so that the number of personnel capable of controlling radiation in an emergency can be increased.

(4) Hydrogen explosion prevention measures

Take measures to prevent the buildup of large amounts of hydrogen in reactor buildings, etc. due to reactor core damage, etc.

(5) Deploy heavy equipment to remove debris

To ensure that work at the station proceeds promptly, take measures to remove debris, such as by deploying heavy equipment like wheel loaders.

 

2. Actions to be taken by Chubu Electric Power (report overview)

(1) Secure the work environment in the central control room

We are deploying additional emergency generators for our emergency ventilation and air conditioning equipment at Hamaoka Nuclear Power Station (to be completed by the end of June 2011), and we have created operating procedures for these generators and for the emergency ventilation and air conditioning equipment.

(2) Secure means of communication within power station during emergencies

We have created procedures to supply power from emergency generators in the event of complete loss of AC power.

Additionally, we have already deployed 30 battery-powered transceivers as a means of communication outdoors and nine rechargeable satellite phones as a means of communication to parties outside the grounds.

Moreover, PHS switching equipment has been placed at elevations of T.P. + about 10 m and higher within buildings, and will be moved to upper floors in buildings hereafter. (To be completed by the end of FY2011)

(3) Secure equipment such as radiation suits, and prepare systems to control radiation

We have decided to deploy 10 radiation suits at Hamaoka Nuclear Power Station (to be completed by the end of July 2011) and have confirmed that equipment is used interchangeably within the nuclear power industry, including radiation suits, personal dosimeters and full masks.

Additionally, we are providing periodic training and drills to Hamaoka Nuclear Power Station employees that include how to use radiation counters so that personnel other than radiation control staff can measure for contamination. Moreover, we have arranged a mechanism under which personnel other than radiation control staff can lend dosimeters and assist with auxiliary duties such as inputting data on worker radiation doses to PCs.

(4) Hydrogen explosion prevention measures

We have created procedures for opening holes in reactor buildings as a measure to discharge leaked hydrogen from reactor buildings and prevent hydrogen explosions there.

We have already deployed enough equipment to open holes at one plant and will deploy enough for all plants hereafter. (To be completed by the end of July 2011)

Additionally, as a medium-/long-term measure, we are installing hydrogen detectors in reactor buildings and installing venting equipment to discharge hydrogen from reactor buildings. (To be completed by the end of the first half of FY2012)

(5) Deploy heavy equipment to remove debris

We have deployed one wheel loader on the grounds at Hamaoka Nuclear Power Station as an emergency safety measure. Further, to improve our ability to remove debris, we have already deployed one caterpillar-track bulldozer, one crawler carrier and one hydraulic shovel.

We also plan to increase the number of staff members who can operate this kind of heavy equipment. (Staff to be increased in early July 2011)

 

Chubu Electric Power will continue to closely monitor the Fukushima Daiichi accident, and as the overall situation becomes clearer and the accident is analyzed and evaluated, will take appropriate measures in response.

*   "Directions of the Minister of Economy, Trade and Industry" refers to "Regarding the Implementation of Measures for Responding to Severe Accidents at Other Nuclear Power Stations Considering the Accident at Fukushima Dai-ichi Nuclear Power Station in 2011 (directions)" (June 07, 2011/Nuclear No. 2), issued June 07, 2011 by the Ministry of Economy, Trade and Industry.