Exelon Comments on Proposed Rule 10 CFR 50 Regarding ASME 2019-2020 Code Editions

Strategic Insights -

The United States Nuclear Regulatory Commission (NRC) has proposed a rule to update its regulations to incorporate by reference the 2019 Edition of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code and the 2020 Edition of the American Society of Mechanical Engineers Operation and Maintenance of Nuclear Power Plants, Division 1: OM Code, for nuclear power plants. Exelon Generation Company, LLC (Exelon) submitted comments on the proposed rule, highlighting several areas of concern and suggesting changes to certain sections.

Key Takeaways:

  • Exelon recommends deleting Section 50.55a(b)(2)(xxvi) regarding pressure testing of Class 1, 2, and 3 mechanical joints, as it is already addressed in licensees' Appendix B Quality Assurance programs.
  • Exelon suggests relaxing the timeframe for submittal of Summary Reports and Owner's Activity Reports for inservice examinations and repair replacement activities from 120 days to a more flexible timeline, allowing licensees to prepare the reports without formally submitting them.
  • Exelon requests further clarification concerning Supplemental Position Indication (SPI) implementation timeline and test due dates, as well as the justification for SPI testing for valves not susceptible to stem-disc separation.
  • Exelon suggests eliminating the supplemental verification requirement for passive valves or limiting it to required valve positions, as sites are modifying or removing valves from the Inservice Testing program to avoid supplemental testing.
  • Exelon requests clarification regarding the required testing due date when implementing the conditions for valves not susceptible to stem-disc separation or OMN-28, as well as the incorporation of EPRI documents as an acceptable method for determining valve stem-disc separation susceptibility.
  • Exelon suggests adding a reference to NRC-approved, performance-based frequencies for SPI, such as Appendix J or other approved performance-based Code Cases, to justify start of SPI testing.
  • Exelon requests further clarification concerning the change to the statement regarding pumps and valves within the scope of the ASME OM Code but not classified as ASME BPV Code Class 1, Class 2, or Class 3, and the intent behind the removal of the statement regarding prior NRC approval for non-Code Class components.

Statistics:

  • Exelon submitted a total of 8 pages of comments on the proposed rule, highlighting several areas of concern and suggesting changes to certain sections.
  • The proposed rule covers various aspects of the ASME 2019-2020 Code Editions, including pressure vessel and piping, operation and maintenance, and quality assurance requirements.
  • The NRC's proposal would update the regulations to incorporate by reference the latest editions and addenda of the ASME codes, as well as the 2011 Addenda to ASME NQA-1-2008 and the 2012 and 2015 Editions of ASME NQA-1.

Sources:

  • Exelon Generation Company, LLC (Exelon)
  • U.S. Nuclear Regulatory Commission (NRC)
  • American Society of Mechanical Engineers (ASME)
  • Nuclear Energy Institute (NEI)
  • EPRI (Electric Power Research Institute)
  • NRC IP 71111.08 "Inservice Inspection Activities"
  • ASME BPV Code, Section XI
  • ASME OM Code, 2012 Edition
  • ASME OM Code, Latest Edition
  • ASME NQA-1-2008
  • ASME NQA-1, Quality Assurance Requirements for Nuclear Facility Applications
  • 10 CFR 50 Proposed Rule (86FR16087, dated March 26, 2021)
  • Docket ID NRC-2018-0290