DIABLO CANYON POWER PLANT DIGITAL PROCESS PROTECTION SYSTEM REPLACEMENT LICENSING EXPERIENCE USING ISG-06

摘要

This paper provides a summary of the preparation of a License Amendment Request (LAR) for replacement of the existing Diablo Canyon Power Plant (DCPP) Eagle 21 digital Process Protection System (PPS) by Pacific Gas & Electric Company (PG&E) using US Nuclear Regulatory Commission (USNRC) Digital I&C (DI&C) Interim Staff Guidance (ISG) document ISG-06. Licensing Process [1]. The USNRC has designated the LAR for the DCPP PPS replacement project as the pilot application for use of DI&C ISG-06. DI&C ISG-06. Revision 1. issued for use on January 19. 2011. describes the licensing process the NRC staff may use to review an LAR for a DI&C modification. The LAR [2] for the replacement of the Eagle 21 PPS was submitted to the NRC on October 26. 2011, was accepted for review [3] on January 13. 2012. and was approved on December 21. 2016. A more detailed review of the specific PPS replacement design including the Defense-In-Depth and Diversity approach is provided in a paper presented at the 2015 conference [12]. The use of pre-application (Phase 0) public meetings with the NRC staff to ensure the PPS replacement design adequately addressed NRC criteria was instrumental to development of the proposed PPS replacement design. This paper discusses the topics discussed in the Phase 0 meetings and the approach utilized by PG&E for the Phase 0 public meetings to support efficient development of the proposed PPS replacement design. PG&E developed a PPS Replacement diversity and defense-in-depth (D3) Assessment Topical Report [4] that was submitted to NRC in 2010 and approved [5] in 2011. This paper discusses the PG&E use of the D3 assessment to evaluate and optimize the initial PPS replacement design prior to submittal of the design to the NRC for approval. The PG&E experience with preparation of the LAR contents and supporting documents and lessons learned during the detailed design and verification phase is discussed.