3:45 PM - 4:00 PM
[HCG30-02] Problems with active fault evaluation in nuclear safety regulation
Keywords:Nuclear power Plant, Active fault, Nuclear Regulation
Usually, the construction of nuclear plants should be conducted as follows: (1) determine if an active fault exists in the premises or in the vicinity, ② estimate earthquake ground motion and ground deformation by active faulting before designing, or ③ avoid. This flow is the basic policy of the NRA examination team that I was a part of, for the New Regulatory Requirements. ③ "Avoid" means moving the location or refraining from constructing at the site. However, there was no corresponding description in the earlier regulatory guide. The New Regulatory Requirements prohibit important facilities from being installed on the outcrop of "faults etc. that may possibly activate in the future". In addition, operating is not permitted unless it meets the requirements. While there have been objections to this, we can discuss again how to better understand "avoiding". However, revising New Regulatory Requirements should be based on social consensus. I will discuss here several scientific subjects regarding ① "active fault recognition" and ② "prediction of earthquake motion and displacement".