ML22083A026

NRR E-mail Capture - Comanche Peak - Request for Additional Information - Request to Adopt TSTF 505 Revision 2

ML22083A026
Person / Time
Site:	Comanche Peak
Issue date:	03/23/2022
From:	Dennis Galvin NRC/NRR/DORL/LPL4
To:	Hicks J TEX Operations Company
References
L-2021-LLA-0085
Download: ML22083A026 (4)

Text

From: Galvin, Dennis Sent: Wednesday, March 23, 2022 5:53 PM To: Jack Hicks (Jack.Hicks@luminant.com)

Cc: Struble, Garry

Subject:

Comanche Peak -Request for Additional Information - Request to Adopt TSTF 505 Revision 2 (EPID: L 2021-LLA-0085)

Attachments: Comanche Peak - TSTF 505 - RAI 2022-03-23.pdf

Dear Mr. Hicks,

By letter dated May 11, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21131A233) as supplemented by letters dated July 13, 2021 (ADAMS Accession No. ML21194A078) and February 17, 2022 (ADAMS Accession No. ML22048B490), Vistra Operations Company, LLC (Vistra OpCo, the licensee) submitted a license amendment request (LAR) to the Nuclear Regulatory Commission (NRC) regarding Comanche Peak Nuclear Power Plant Units 1 and 2 (Comanche Peak). The proposed amendment would revise Technical Specification (TS) requirements to permit the use of risk informed completion times for actions to be taken when limiting conditions for operation are not met. The proposed changes are based on TSs Task Force Traveler (TSTF) 505, Revision 2, Provide Risk Informed Extended Completion Times - RITSTF Initiative 4b, dated July 2, 2018 (ADAMS Accession No. ML18183A493). The U.S. NRC issued a final model safety evaluation (SE) approving TSTF 505, Revision 2, on November 21, 2018 (ADAMS Accession No. ML18269A041).

The NRC staff has determined that additional information is needed to complete its review. The requests for additional information (RAIs) were transmitted to the licensee in draft form on March 21, 2022. Garry Struble of your staff on March 22, 2022, indicated that no clarification call was needed, and the licensee agreed to provide responses to the RAls by April 21, 2022. The NRC staff agreed with this date.

If you have any questions, please contact me at (301) 415-6256 or Dennis.Galvin@nrc.gov.

Respectfully, Dennis Galvin Project Manager U.S Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Division of Operating Reactor Licensing Licensing Project Branch 4 301-415-6256 Docket Nos. 50-445 and 50-446

Hearing Identifier: NRR_DRMA Email Number: 1566 Mail Envelope Properties (SA1PR09MB811183E5AB9E378E61CB8315FB189)

Subject:

Comanche Peak -Request for Additional Information - Request to Adopt TSTF 505 Revision 2 (EPID: L 2021-LLA-0085)

Sent Date: 3/23/2022 5:53:11 PM Received Date: 3/23/2022 5:53:00 PM From: Galvin, Dennis Created By: Dennis.Galvin@nrc.gov Recipients:

"Struble, Garry" <Garry.Struble@luminant.com>

Tracking Status: None "Jack Hicks (Jack.Hicks@luminant.com)" <Jack.Hicks@luminant.com>

Tracking Status: None Post Office: SA1PR09MB8111.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 1847 3/23/2022 5:53:00 PM Comanche Peak - TSTF 505 - RAI 2022-03-23.pdf 119306 Options Priority: Normal Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST TO ADOPT RISK-INFORMED EXTENDED COMPLETION TIMES VISTRA OPERATIONS COMPANY LLC COMANCHE PEAK UNIT 1 AND 2 DOCKET NOS. 50-445 AND 50-446 By letter dated May 11, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21131A233) as supplemented by letters dated July 13, 2021 (ADAMS Accession No. ML21194A078) and February 17, 2022 (ADAMS Accession No. ML22048B490), Vistra Operations Company, LLC (Vistra OpCo, the licensee) submitted a license amendment request (LAR) to the Nuclear Regulatory Commission (NRC) regarding Comanche Peak Nuclear Power Plant Units 1 and 2 (Comanche Peak). The proposed amendment would revise Technical Specification (TS) requirements to permit the use of risk informed completion times for actions to be taken when limiting conditions for operation are not met. The proposed changes are based on TSs Task Force Traveler (TSTF) 505, Revision 2, Provide Risk Informed Extended Completion Times - RITSTF Initiative 4b, dated July 2, 2018 (ADAMS Accession No. ML18183A493). The U.S. NRC issued a final model safety evaluation (SE) approving TSTF-505, Revision 2, on November 21, 2018 (ADAMS Accession No. ML18269A041).

To complete its review, the NRC staff requests the following additional information.

APLC RAI-1 By , Revision 2, Provide Risk-Informed Extended.|letter dated February 17, 2022]], the licensee supplemented its license amendment request to provide responses to audit questions. Audit Question 17 addressed whether seismic core damage frequency and large early release frequency (CDF/LERF) values used in the proposed Comanche Peak Risk-Informed Completion Time program were consistent with the guidelines in Nuclear Energy Institute (NEI) 06-09, Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines, Industry Guidance Document, as approved by the NRC staff in NEI 06-09, Revision 0-A (ADAMS Accession No. ML071200238).

In response to Audit Question 17, the licensee in part revised Enclosure 4, Table E4-1, Seismic Results Summary for CPNPP to provide updated seismic CDF/LERF values. However, corresponding information in Enclosure 5, Table 1, CPNPP Units 1 and 2 Baseline PRA Model Results, was not updated. Specifically, Enclosure 5, Table 1 is not corrected for seismic CDF/LERF values, and does not appear to be consistent with the Revised Table E4-1. Please confirm that the seismic CDF/LERF values in Enclosure 5, Table 1 should be identical to those in the revised Enclosure 4, Table E4-1 and correct Enclosure 5, Table 1. If it cannot be confirmed that the values in Enclosure 4, Table E4-1 and Enclosure 5, Table 1 are identical, please justify the basis and purpose of different values of seismic CDF/LERF used in the same application.

STSB RAI-1 TSTF-505 Revision 2 proposes several administrative controls for the adoption of a Risk Informed Completion Time (RICT) Program at Technical Specification (TS) 5.5.[18] of the Standard TS markup. TSTF-505 Revision 2 TS 5.5.[18] Paragraph e contains administrative controls for methods to assess the risk from extending the limiting conditions for operation action statement completion times. TSTF-505 Revision 2 and the model safety evaluation (SE) have slightly different wording for Paragraph e. TSTF-505 Revision 2 reads used to support this license amendment while the model SE uses the improved phrase, approved for use with this program In , Revision 2, Provide Risk-Informed Extended.|letter dated February 17, 2022]], the licensees response to Audit Question 26 affected Paragraph e of the proposed administrative controls for the Comanche Peak RICT Program at TS 5.5.23 by changing the phrase this license amendment to this program. However, the proposed Paragraph e in the February 17, 2022, supplement is not consistent with the Paragraph e in either TSTF 505 Revision 2 or the model SE. Please revise Comanche Peak TS 5.5.23 Paragraph e to be consistent with the RICT program as discussed in the model SE for TSTF-505 Revision 2. Alternatively, provide justification for the variation provided in the supplement dated February 17, 2022.