CP-202400092, (CPNPP) - Supplement to Application to Revise Technical Specifications to Adopt TSTF-591, Revise Risk Informed Completion Time (RICT) Program

(CPNPP) - Supplement to Application to Revise Technical Specifications to Adopt TSTF-591, Revise Risk Informed Completion Time (RICT) Program

ML24092A236
Person / Time
Site:	Comanche Peak
Issue date:	04/01/2024
From:	John Lloyd Vistra Operations Company
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
CP-202400092, TXX-24019
Download: ML24092A236 (1)

Text

Comanche Peak Nuclear Power Plant Jay Lloyd Vice President Nuclear Engineering P.O. Box 1002 6322 North FM 56 Glen Rose, TX 76043

CP-202400092 TXX-24019 April 1, 2024

ATTN: Document Control Desk Ref 10 CFR 50.90 U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Comanche Peak Nuclear Power Plant (CPNPP)

Docket Nos. 50-445 and 50 -446

Subject:

Supplement to Application to Revise Technical Specifications to Adopt TSTF-591, "Revise Risk Informed Completion Time (RICT) Program"

References:

1. Letter, J. Lloyd to NRC, "Application to Revise Technical Specifications to Adopt TSTF-591,

"Revise Risk Informed Completion Time (RICT) Program "," February 28, 2024, ML24059A390.

2. Letter, TSTF to NRC, "Correction of TSTF-591, Revision 0, "Revise the Risk Informed Completion Time (RICT) Program. ", " March 22, 2024, TSTF-24-03.

Dear Sir or Madam :

By Reference 1, Vistra Operations Company LLC (Vistra OpCo) requested adoption of TSTF-591, "Revise Risk Informed Completion Time (RICT) Program," which is an approved change to the Standard Technical Specifications (STS), into the CPNPP Units 1 and 2 Technical Specifications (TS). After submittal of Reference 1, Vistra OpCo was made aware of an error in TSTF-591 related to the provided TS mark-up. To address this error as recommended in Reference 2, Vistra OpCo submits the following attachments on a replacement page bases as a supplement to Reference 1. Attachment 1 provides replacement TS mark-up pages. Attachment 2 provides replacement revised (clean) TS pages.

This communication contains no new commitments regarding CPNPP Units 1 and 2.

Should you have any questions, please contact Nie Boehmisch at (254) 897-5064 or nicholas.boehmisch@luminant.com.

I state under penalty of perjury that the foregoing is true and correct. Executed on April 1, 2024.

Sincerely,

Jay Lloyd

Attachments: 1. Proposed Technical Specification Changes (Mark-Up)

2. Revised Technical Specification Pages

6555 SIERRA DRIVE IRVING, TEXAS 75039 o 214-812-4600 VISTRACORP.COM TXX-24019 Page 2 of 2

cc:

NRC Regional Administrator, Region IV NRC Project Manager, CPNPP NRC Senior Resident Inspector, CPNPP NRC Resident Inspector, CPNPP Attachment 1 to TXX-24019

Proposed Technical Specification Changes (Mark-Up)

No Changes. For Information Only. Programs and Manuals 5.5

5.5 Programs and Manuals

5.5.23 Risk Informed Completion Time Program

This program provides controls to calculate a Risk Informed Completion Time (RICT) and must be implemented in accordance with NEI 06-09-A, Revision 0, "Risk-Managed Technical Specifications (RMTS) Gu idelines." The program shall include the following:

a. The RICT may not exceed 30 days;

b. A RICT may only be utilized in MODE 1 and 2;

c. When a RICT is being used, any change to the plant configuration, as define d in NEI 06-09-A, Appendix A, must be considered for the effect on the RICT.

1. For planned changes, the revised RICT must be determined prior to implementation of the change in configuration.

2. For emergent conditions, the revised RICT must be determined with in the time limits of the Required Action Completion Time (i.e., not the RICT) or 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after the plant configuration change, whichever is less.

3. Revising the RICT is not required if the plant configuration chang e would lower plant risk and would result in a longer RICT.

d. For emergent conditions, if the extent of condition evaluation for inoperable structures, systems, or components (SSCs) is not complete prior to exceed ing the Completion Time, the RICT shall ac count for the increased possibility of common cause failure (CCF) by either:

1. Numerically accounting for the increased possibility of CCF in the RICT calculation; or

2. Risk Management Actions (RMAs) not already credited in the RICT calculation shall be implemented that support redundant or diverse SSCs that perform the function(s) of the inoperable SSCs, an d, if practicable, reduce the frequency of initiating events that challenge th e function(s) performed by the inoperable SSCs.

COMANCHE PEAK - UNITS 1 AND 2 5.5-18Amendment No. 183 Programs and Manuals 5.5

5.5 Programs and Manuals

5.5.23 Risk Informed Completion Time Program (continued)

e. The risk assessment approaches and methods shall be acceptable to the NRC. The plant PRA shall be based on the as-built, as-operated, and maintained plant; and reflect the operating experience at the plant, as specified in Regulatory Guide 1.200, Revision 2. Methods to assess the risk from extending the Completion Times must be PRA methods approved for use with this program, or other methods approved by the NRC for generic use; and any change in the PRA methods to assess risk that are outside these approval boundaries require prior NRC approval.

e. A RICT calculation must include the following hazard groups: Internal flood and internal events PRA model, internal fire PRA model, seismic penalty factor, and extreme winds and tornado penalty factor. Changes to these means of assessing the hazard groups require prior NRC approval.

f. The PRA models used to calculate a RICT shall be maintained and upgraded in accordance with the processes endorsed in the regulatory positions of Regulatory Guide 1.200, Revision 3, "Acceptability of Probabilistic Risk Assessment Results for Risk-Informed Activities."

g. A report shall be submitted in accordance with Specification 5.6.10 before a newly developed method is used to calculate a RICT.

COMANCHE PEAK - UNITS 1 AND 2 5.5-19Amendment No. 183 Reporting Requirements 5.6

5.6 Reporting Requirements

5.6.9 Steam Generator Tube Inspection Report (continued)

d. An analysis summary of the tube integr ity conditions predicted to exist at the next scheduled inspection (the forward-looking tube integrity assessment) relative to the applicable performance criteria, including the analysis methodology, inputs, and results;

e. The number and percentage of tubes plugged to date, and the effective plugging percentage in each SG;

f. The results of any SG secondary side inspections;

g. For Unit 2, the primary to secondary leakage rate observed in each SG (if it is not practical to assign the leakage to an individual SG, the entire primary to secondary leakage should be conservatively assumed to be from one SG) during the cycle preceding the inspecti on which is the subject of the report;

h. For Unit 2, the calculated accident induced leakage rate from the portion of the tubes below 14.01 inches from the top of the tubesheet for the most limiting accident in the most limiting SG. In addition, if the calculated accident induced leakage rate from the most limiting accident is less than 3.16 times the maximum operational primary to secondary leakage rate, the report should describe how it was determined; and

i. For Unit 2, the results of monitoring for tube axial displacement (slippage). If slippage is discovered, the implications of the discovery and corrective action shall be provided.

5.6.10 Risk Informed Completion Time (RICT) Program Upgrade Report

A report describing newly developed methods and their implementation must be submitted following a probabilistic risk assessment (PRA) upgrade associated with newly developed methods and prior to the first use of those methods to calculate a RICT. The report shall include:

a. The PRA models upgraded to include newly developed methods;

b. A description of the acceptability of the newly developed methods consistent with Section 5.2 of PWROG-19027-NP, Revision 2, "Newly Developed Method Requirements and Peer Review;"

c. Any open findings from the peer-review of the implementation of the newly developed methods and how those findings were dispositioned; and

d. All changes to key assumptions related to newly developed methods or their implementation.

COMANCHE PEAK - UNITS 1 AND 2 5.6-6Amendment No. 158, 182 Attachment 2 to TXX-24019

Revised Technical Specification Pages

No Changes. For Information Only. Programs and Manuals 5.5

5.5 Programs and Manuals

5.5.23 Risk Informed Completion Time Program

This program provides controls to calculate a Risk Informed Completion Time (RICT) and must be implemented in accordance with NEI 06-09-A, Revision 0, "Risk-Managed Technical Specifications (RMTS) Gu idelines." The program shall include the following:

a. The RICT may not exceed 30 days;

b. A RICT may only be utilized in MODE 1 and 2;

c. When a RICT is being used, any change to the plant configuration, as defined in NEI 06-09-A, Appendix A, must be considered for the effect on the RICT.

1. For planned changes, the revised RICT must be determined prior to implementation of the change in configuration.

2. For emergent conditions, the revised RICT must be determined with in the time limits of the Required Action Completion Time (i.e., not the RICT) or 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after the plant configuration change, whichever is less.

3. Revising the RICT is not required if the plant configuration change would lower plant risk and would result in a longer RICT.

d. For emergent conditions, if the extent of condition evaluation for inoperable structures, systems, or components (SSCs) is not complete prior to exceeding the Completion Time, the RICT shall ac count for the increased possibility of common cause failure (CCF) by either:

1. Numerically accounting for the increased possibility of CCF in the RICT calculation; or

2. Risk Management Actions (RMAs) not already credited in the RICT calculation shall be implemented that support redundant or diverse SSCs that perform the function(s) of the inoperable SSCs, an d, if practicable, reduce the frequency of initiating events that challenge the function(s) performed by the inoperable SSCs.

COMANCHE PEAK - UNITS 1 AND 2 5.5-18Amendment No. 183 Programs and Manuals 5.5

5.5 Programs and Manuals

5.5.23 Risk Informed Completion Time Program (continued)

e. A RICT calculation must include the following hazard groups: Internal flood and internal events PRA model, internal fire PRA model, seismic penalty factor, and extreme winds and tornado penalty factor. Changes to these means of assessing the hazard groups require prior NRC approval.

f. The PRA models used to calculate a RICT shall be maintained and upgraded in accordance with the processes endorsed in the regulatory positions of Regulatory Guide 1.200, Revision 3, "Acceptability of Probabilistic Risk Assessment Results for Risk-Informed Activities."

g. A report shall be submitted in accordance with Specification 5.6.10 before a newly developed method is used to calculate a RICT.

COMANCHE PEAK - UNITS 1 AND 2 5.5-19Amendment No. 183 Reporting Requirements 5.6

5.6 Reporting Requirements

5.6.9 Steam Generator Tube Inspection Report (continued)

d. An analysis summary of the tube integr ity conditions predicted to exist at the next scheduled inspection (the forward-looking tube integrity assessment) relative to the applicable performance criteria, including the analysis methodology, inputs, and results;

e. The number and percentage of tubes plugged to date, and the effective plugging percentage in each SG;

f. The results of any SG secondary side inspections;

g. For Unit 2, the primary to secondary leakage rate observed in each SG (if it is not practical to assign the leakage to an individual SG, the entire primary to secondary leakage should be conservatively assumed to be from one SG) during the cycle preceding the inspecti on which is the subject of the report;

h. For Unit 2, the calculated accident induced leakage rate from the portion of the tubes below 14.01 inches from the top of the tubesheet for the most limiting accident in the most limiting SG. In addition, if the calculated accident induced leakage rate from the most limiting accident is less than 3.16 times the maximum operational primary to secondary leakage rate, the report should describe how it was determined; and

i. For Unit 2, the results of monitoring for tube axial displacement (slippage). If slippage is discovered, the implications of the discovery and corrective action shall be provided.

5.6.10 Risk Informed Completion Time (RICT) Program Upgrade Report

A report describing newly developed methods and their implementation must be submitted following a probabilistic risk assessment (PRA) upgrade associated with newly developed methods and prior to the first use of those methods to calc ulate a RICT. The report shall include:

a. The PRA models upgraded to include newly developed methods;

b. A description of the acceptability of the newly developed methods consistent with Section 5.2 of PWROG-19027-NP, Revision 2, "Newly Developed Method Requirements and Peer Review;"

c. Any open findings from the peer-review of the implementation of the newly developed methods and how those findings were dispositioned; and

d. All changes to key assumptions related to newly developed methods or their implementation.

COMANCHE PEAK - UNITS 1 AND 2 5.6-6Amendment No. 158, 182