Regulatory Guide 1.187: Difference between revisions

Public Meeting Summary, June 25, 2019
	ML19204A176
Person / Time
Issue date:	07/23/2019
From:	Tekia Govan; NRC/NRR/DIRS/IRGB
To:	Philip Mckenna; NRC/NRR/DIRS/IRGB
	Govan T, 415-6197, NRR/DIRS
References
	NEI 96-07, RG-1.187, Rev 2
	Download: ML19204A176 (6)
	v • d • e

Revision as of 15:17, 19 October 2019

UNITED STATES

NUCLEAR REGULATORY COMMISSION

WASHINGTON, D.C. 20555-0001 July 23, 2019 MEMORANDUM TO: Philip J. McKenna, Chief ROP Support and Generic Communication Branch Division of Inspection and Regional Support Office of Nuclear Reactor Regulation FROM: Tekia V. Govan, Project Manager /RA/

ROP Support and Generic Communication Branch Division of Inspection and Regional Support Office of Nuclear Reactor Regulation SUBJECT: SUMMARY OF THE PUBLIC MEETING ON THE DRAFT

REGULATORY GUIDE 1.187, REVISION 2, THAT ENDORSES

NUCLEAR ENERGY INSTITUTE 96-07, APPENDIX D, HELD ON

JUNE 25, 2019 On June 25, 2019, the U.S. Nuclear Regulatory Commission (NRC) staff held a Category 2 public meeting with the Nuclear Energy Institute (NEI) to discuss the usability of NEI 96-07, Appendix D, Supplemental Guidance for Application of 10 CFR 50.59 to Digital Modifications (Agencywide Documents Access and Management System (ADAMS) Accession No. ML18338A389), as endorsed by draft Regulatory Guide (RG) 1.187, Revision 2, Guidance for Implementation of 10 CFR 50.59, Changes, Tests, and Experiments (ADAMS Accession No. ML19045A435).

Background The NRC staff issued for public comment draft RG 1.187, Revision 2, that will provide guidance on complying with the requirements of Title 10 of the Code of Federal Regulations (10 CFR)

Section 50.59 when performing a digital instrumentation and controls (digital I&C) modification.

Specifically, NEI 96-07, Appendix D, Revision 0, was submitted to the NRC on November 30, 2018. As discussed in Section C of RG 1.187, the staff endorses NEI 96-07 and finds that it provides an acceptable approach for the application of 10 CFR 50.59 guidance when conducting digital I&C modifications, with certain exceptions and clarifications. Draft RG 1.187, Revision 2, was issued for public comment to facilitate the Commissions direction in the Staff Requirements Memorandum (SRM) SECY-16-0070, Staff Requirements SECY-16-0070 Integrated Strategy to Modernize the Nuclear Regulatory Commissions Digital Instrumentation and Control Regulatory Infrastructure (ADAMS

Accession No. ML16299A157). The NRC staff has engaged the public, NEI, and industry representatives to improve the guidance for applying 10 CFR 50.59 to digital I&C-related CONTACT: Tekia V. Govan, NRR/DIRS

(301) 415-6197

P. McKenna 2 design modifications as part of a broader effort to modernize the regulatory infrastructure for digital I&C. This meeting, on June 25, 2019, serves as an additional opportunity to engage the public and the nuclear industry prior to the close of the public comment period on the draft RG

1.187, Revision 2, on July 15, 2019.

Meeting Summary The NRC and industry management made brief opening remarks, and introductions were made by all in attendance. The NRC staff stated the objective of the meeting which was to conduct table-top exercises of digital I&C upgrades in which applying NEI 96-07, Appendix D, Criterion 6 guidance was met. During this meeting, NEI presented four examples and NRC presented three examples (ADAMS Accession Nos. ML19176A070 and ML19170A329), respectively related to NEI 96-07, Appendix D, Criterion 6 guidance. All the examples were presented with a starting point where it could not be demonstrated that a common cause failure across multiple trains was sufficiently low through a qualitative assessment as described in regulatory issue summary 2002-22, Supplement 1. The examples were only discussed against 10 CFR 50.59, Criterion 6, which is applicable to modifications that create a possibility for a malfunction of an

[structure, system, and component (SSC)] important to safety with a different result than any previously evaluated in the final safety analysis report (as updated). The NRC staff has taken an exception in draft RG 1.187, Revision 2, against the documentation of NEI 96-07, Appendix D, Criterion 6, Section 4.3.6.

During the table-top exercises the NRC staff and NEI generally came to the same conclusion as to whether the digital I&C modification in the exercise could be performed under 10 CFR 50.59 or if a license amendment request (LAR) would be required.

The major take ways from the meeting were:

NEI clarified that the safety analysis in NEI 96-07, Appendix D is not exclusive to updated final safety analysis report (UFSAR), Chapter 15, Accident Analysis. NEI

stated that the term safety analysis applies to any portion of the UFSAR where a safety analysis is performed.

Some of the digital modification examples provided by NEI demonstrated that a different interpretation of the current wording in the draft RG 1.187, Revision 2, could result in a licensee submitting a LAR when it is not required.

NEI and NRC staff agreed that working through the examples using NEI 96-07, Appendix D guidance should produce the same result as using the current guidance in NEI 96-07 base document.

NEI and NRC staff agreed with the definition of Malfunction of an SSC Important to Safety in NEI 96-07. There was discussion on what a different result meant in the regulation under 10 CFR 50.59, Criterion 6. Specifically, it was discussed where a modification should be evaluated by the malfunction different result or the safety analysis different result. The NEI 96-07 base document discusses malfunction different result, but NEI 96-07, Appendix D now discusses the safety analysis different result. There was action taken by NEI to evaluate the difference in terminology between the NEI 96-07 base document and NEI 96-07, Appendix D.

NEI agreed that they needed to revise the wording in NEI 96-07, Appendix D,

Section 4.3.6, steps 1 through 4 and to clarify the step 6 wording as it relates to safety analysis have become invalid due to their basic assumptions no longer being

P. McKenna 3 valid. Based on the current reading of Section 4.3.6, step 6, the NRC staff concluded that modifications could result in the need for a LAR.

The NRC staff did not make any decisions or took any agency positions during this meeting.

The enclosure provides the attendance list for this meeting.

Conclusion The meeting concluded with NEI stating that they will be able to meet the deadline for public comment period on draft RG 1.187, Revision 2, that closed on July 15, 2019. NEI stated that they will have recommended changes to NEI 96-07, Appendix D that will be included as a part their comment response including additional examples that clarify the discussion held during this meeting. The NRC staff stated that with the additional guidance and examples that are expected to be submitted as a part of NEIs public comment, there will be a need for another public comment period and potentially another public meeting to discuss these latest revisions to the NEI guidance.

Enclosure:

As stated

ML19204A176 concurred via e-mail*

OFFICE NRR/DIRS/IRGB* NRR/DIRS/IRGB* NRR/DIRS/IRGB* NRR/DIRS/IRGB*

NAME TGovan IBetts PMcKenna TGovan DATE 07/23/2019 07/23/2019 07/23/2019 07/23/2019

LIST OF ATTENDEES

SUMMARY OF THE PUBLIC MEETING ON THE DRAFT REGULATORY GUIDE 1.187, REVISION 2 THAT ENDORSES NUCLEAR ENERGY INSTITUTE 96-07, APPENDIX D, HELD

ON JUNE 25, 2019 June 25, 2019, 1:00 PM to 4:30 PM

NRC One White Flint North

11555 Rockville Pike O-11B04 Rockville, MD

ATTENDEE ORGANIZATION

1. Rossnyev Alvarado NRC