ML20280A563

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Summary of Teleconference Meeting with Union Electric Company (Dba Ameren Missouri) for Callaway Plant, Unit 1, on Pre-Application for LARs on TSTF-439, TSTF-505, and Title 10 CFR 50.69 Categorization Program (EPID L-2020-LRM-0072
ML20280A563
Person / Time
Site: Callaway Ameren icon.png
Issue date: 10/21/2020
From: Mahesh Chawla
Plant Licensing Branch IV
To:
Chawla M
References
EPID L-2020-LRM-0072
Download: ML20280A563 (5)


Text

October 21, 2020 LICENSEE:

Union Electric Company FACILITY:

Callaway Plant, Unit No. 1

SUBJECT:

SUMMARY

OF SEPTEMBER 8, 2020, TELECONFERENCE MEETING WITH UNION ELECTRIC COMPANY REGARDING PROPOSED LICENSE AMENDMENT REQUESTS TO ADOPT TECHNICAL SPECIFICATIONS TASK FORCE (TSTF-439), TSTF-505, AND 10 CFR 50.69 CATEGORIZATION PROGRAM FOR CALLAWAY PLANT, UNIT No. 1 (EPID L-2020-LRM-0072)

On September 8, 2020, a Category 1 public teleconference was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Union Electric Company dba Ameren Missouri (the licensee). The purpose of this meeting was to discuss the licensees plans and schedule for the following two proposed license amendment requests (LARs) for Callaway Plant, Unit No. 1: (1) to adopt Technical Specifications Task Force (TSTF) Travelers TSTF-439, Eliminate Second Completion Times Limiting Times from Discovery of Failure to Meet and LCO

[Limiting Condition for Operation] and TSTF-505, Provide Risk-Informed Extended Completion Times - RITSTF [Risk-Informed TSTF] Initiative 4b; and (2) to adopt Title 10 of the Code of Federal Regulations Section 50.69 (10 CFR 50.69), Risk-informed categorization and treatment of structures, systems, and components for nuclear power reactors.

The meeting notice and agenda, dated August 13, 2020, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML20240A344. A list of attendees is enclosed.

The licensee presented meeting slides, which can be found in ADAMS at Accession No. ML20248H467. The meeting slides included the scope of the LARs, optional variations from TSTF-505 license amendment development, probabilistic risk assessment (PRA) model technical adequacy, open findings and observations, PRA model uncertainties and assumptions, external hazards, potential review efficiencies, and timeline for submissions. The licensee also stated that the 10 CFR 50.69 LAR is expected to be submitted in the late third quarter of 2020, and TSTF-505 is expected to be submitted in the fourth quarter of 2020.

TSTF-439 will be submitted in conjunction with TSTF-505.

The NRC staff discussed with the licensee that the future LARs should consider the following items as part of the upcoming submittals; As shown on Slide 5 of the licensees presentation, ensure all aspects of the methodology are addressed.

As shown on Slide 14 of the licensees presentation, it is stated that Callaway implemented the methodology provided in PWROG [Pressurized-Water Reactor Owners

Group]-18027-NP for assessing the loss of room cooling in PRA modelling. During the meeting, the licensee also mentioned that it is using a non-standard LCO 3.7.5 (concerning the auxiliary feedwater system), which was not in the licensees presentation slides. The NRC staff would like this to be addressed in the LAR.

PRA Technical Adequacy Provide a high-level summary in the LAR for the NRC staff to assess information related to facts and observations closure consistent with the Appendix X guidance and the staff conditions of acceptance were considered.

For fire probabilistic risk assessment, address any outstanding or open commitments stemming from the National Fire Protection Association (NFPA)-805 that overlap and potentially impact the PRA acceptability for the risk-informed applications.

Include any credit for Diverse and Flexible Mitigation Strategy (FLEX). Describe if and how the permanent or portable equipment is considered (i.e., consistency with staff memo).

NFPA-805 was approved in 2014, and the licensee has completed its transition process. It would be prudent to ensure that any methodologies that have been further addressed via frequently asked questions or updated guidance documents are considered in preparation of the subject LARs.

PRA Model Uncertainties and Assumptions In disposition of crediting applicable sensitivities prescribed in guidance, be clear and provide the basis of its applicability.

It will be prudent to review applicable precedent safety evaluations addressing seismic PRA assumptions and sources of uncertainty.

Combined TSTF-439 and TSTF-505 It would be helpful if separate evaluations are provided for each TSTF.

Provide a discussion that describes the overall loss-of-function assessment for all LCOs that are included in the scope of the LAR and any criteria (i.e., design success criteria, PRA success criteria) used to determine the loss-of-function.

Per Slide 10 of the licensees presentation, provide the basis for use of surrogate and why it is sufficient for the function being assessed.

The licensee stated that the LARs would address the comments and concerns raised by the NRC staff in this teleconference.

No regulatory decisions were made as a result of this teleconference.

Members of the public were in attendance. Public Meeting Feedback forms were not received.

Please direct any inquiries to Mahesh.Chawla@nrc.gov or contact me at 301-415-8371.

/RA/

Mahesh L. Chawla, Project Manager Plant Licensing Branch III Division Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-483

Enclosure:

List of Attendees cc: Listserv

LIST OF ATTENDEES SEPTEMBER 8, 2020 PRE-SUBMITTAL TELECONFERENCE WITH UNION ELECTRIC COMPANY REGARDING PROPOSED LICENSE AMENDMENT REQUESTS TO ADOPT TECHNICAL SPECIFICATIONS TASK FORCE (TSTF)-439, TSTF-505 AND 10 CFR 50.69 FOR CALLAWAY PLANT, UNIT NO. 1 U.S. Nuclear Regulatory Commission M. Benson A. Brown M. Chawla J. Circle A. Foli B. Fu B. Grenier J. Huang C. Li M. Li E. Miller K. Nguyen R. Pascarelli J. Robinson T. Scarbrough G. Singh K. Tetter B. Titus S. Vasavada K. West D. Woodyatt D. Wu Union Electric Company N. Allen S. Banker A. Burgess N. Casey M. Degonish J. Doughty T. Elwood J. Hiller B. Hryciw B. Huhmann J. Kosky J. Kovar E. Matthews S. Meyer I. Mulhern R. Orr T. Schmidt R. Wink Pacific Northwest National Laboratory S. Short Public R. Burg (Engineering Planning and Management (EPM), Inc.

Meeting Notice, ML20240A344 Meeting Summary, ML20280A563

  • via e-mail OFFICE NRR/DORL/LPL4/PM NRR/DORL/LPL4/LA*

NRR/DRA/APLA/BC*

NAME MChawla PBlechman RPascarelli DATE 10/21/2020 10/21/2020 10/06/2020 OFFICE NRR/DORL/LPL4/BC*

NRR/DORL/LPL4/PM*

NAME JDixon-Herrity MChawla DATE 10/21/2020 10/21/2020