Press Release
Measures for Compliance with New Regulatory Standards at Hamaoka Nuclear Power Station (Implementation of Countermeasures against Overflow from Intake Ponds and Other Such Facilities)
April 26, 2013
Chubu Electric Power Co.,Inc.
At present, the formulation of new regulatory standards is under way at the Nuclear Regulation Authority (NRA), and draft regulation provisions for the new regulatory standards were published on April 10, 2013. The draft regulation provisions include the tsunami countermeasures and countermeasures against severe accidents, such as installation of filter vent equipment, which Chubu Electric Power is presently engaged in. In addition, they also include regulatory requirements for consideration of further countermeasures and specific measures. Chubu Electric Power aims to achieve prompt conformance with the new regulatory standards, and we intend to proceed with phased examination of the necessary measures while continuing to closely observe the circumstances in which the standards are being formulated by the NRA.
We are proceeding with installation of filter vent equipment and other severe accident countermeasures with the goal of completing these measures for Units 3 and 4 by the end of FY2014.
In light of design principles regarding tsunami stated in the draft regulation provisions, Chubu Electric Power has now also decided to implement Countermeasures against Overflow from Intake Ponds and Other Such Facilities. We intend to pursue this, too, with the goal of completing the work by the end of FY2014.
1. Circumstances of the Consideration of New Regulatory Standards
Since Chubu Electric Power announced tsunami countermeasures in July 2011, we have been implementing voluntary countermeasures aimed at the continuing enhancement of safety. These include our decisions made in December 2012: raising the height of the tsunami protection wall as well as other reinforced tsunami countermeasures; the installation of filter vent equipment and other such severe accident countermeasures. Meanwhile, the Nuclear Regulation Authority has been promoting the formulation of new regulatory standards, and draft regulation provisions for new regulatory standards were published on April 10, 2013. These draft regulation provisions include the tsunami countermeasures and severe accident countermeasures that Chubu Electric Power is presently engaged in. In addition, they also include regulatory requirements for consideration of further countermeasures and specific measures. Specifically, this includes design principles with regard to tsunami that call for "prevention of the arrival and inflow over land of wave runup from design basis tsunami onto sites where facilities belonging to the S Class of seismic importance are located. In addition, inflow from intake channels, discharge channels, and other such channels is to be prevented." The requirements also refer to " portable equipment (for power supply and water injection) reinforcement," "emergency control room setting up," and so on.
Chubu Electric Power aims to achieve prompt conformance with the new regulatory standards, and we intend to proceed with gradual consideration of the necessary measures while continuing to closely observe the circumstances in which the standards are being formulated by the NRA.
2. Circumstances of the Engagement with Severe Accident Countermeasures
As regards the severe accident countermeasures announced in December 2012, which include the installation of filter vent equipment, we have completed our study of basic specifications for Units 3 and 4 and are now pursuing procedures for the government approval required to undertake the work, which we plan to start in June of this year. Our aim is to complete the countermeasures by the end of FY2014. As concerns Unit 5, while we are studying ways to deal with inflow of seawater due to damage to the main condenser tubes, we are proceeding to study specific measures.
3. Implementation of Countermeasures against Overflow from Intake Ponds and Other Such Facilities
In light of the design principles regarding tsunami that are stated in the draft regulation provisions, Chubu Electric Power has decided to implement Countermeasures Against Overflow from Intake Ponds and Other Such Facilities. This includes building overflow prevention walls around the intake ponds for Units 3 to 5, and our aim is to complete construction by the end of FY2014.
In conjunction with this initiative, we have cancelled implementation of the change in height of the flood protection wall around the seawater pump from 1.5 m to 3 m (announced December 2012). This had been planned for the purpose of reinforcing flood prevention measures against tsunami intrusion on the Station site (Reinforcement of Flood Prevention Measures 1).
The impact on performance for this quarter will be minimal.
Chubu Electric Power is committed to continuing steady progress with measures for further enhancement of the safety of Hamaoka Nuclear Power Station. At the same time, we will also do everything in our power to provide detailed explanations of the content of those measures so as to contribute to the peace of mind of the local community and of society at large.