RS-25-042, License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray

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License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray
ML25171A137
Person / Time
Site: Quad Cities  Constellation icon.png
Issue date: 06/20/2025
From: Humphrey M
Constellation Energy Generation
To:
Office of Nuclear Reactor Regulation, Document Control Desk
References
RS-25-042
Download: ML25171A137 (1)
v • d • e


Text

4300 Winfield Road Warrenville, IL 60555 630 657 2000 Office RS-25-042 10 CFR 50.90 June 20, 2025 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265

Subject:

License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray

Reference:

Letter from R. Kuntz (U.S. NRC) to D. P. Rhoades (Constellation Energy Generation, LLC), "Quad Cities Nuclear Power Station, Units 1 and 2 - Issuance of Amendment Nos. 302 and 298 Re: Adoption of TSTF-505, 'Provide Risk Informed Extended Completion Times - RITSTF Initiative 4B' and TSTF-591

'Revise Risk Informed Completion Time (RICT) Program' (EPID L-2023-LLA-0084)," dated August 8, 2024 (ADAMS Accession No. ML24183A108)

In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Constellation Energy Generation, LLC (CEG) requests an amendment to Renewed Facility Operating License Nos. DPR-29 and DPR-30 for Quad Cities Nuclear Power Station (QCNPS), Units 1 and 2. The proposed amendment modifies Technical Specifications (TS) 3.6.2.4, "Residual Heat Removal (RHR) Suppression Pool Spray," to permit the use of Risk Informed Completion Times for the condition of one RHR suppression pool spray subsystem inoperable. In Amendment Nos. 302 and 298 for QCNPS, Units 1 and 2 (i.e., Reference),

respectively, the NRC approved adoption of Technical Specifications Task Force (TSTF)

Traveler TSTF-505, Revision 2, "Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b." The proposed change also modifies the Operating Licenses for QCNPS, Units 1 and 2, to remove license conditions associated with one-time actions that were added to the Operating Licenses as part of the Reference amendments.

  • provides a description and assessment of the proposed changes, the requested confirmation of applicability, and plant-specific verifications.
  • provides the existing TS and Operating License pages marked up to show the proposed changes.

June 20, 2025 U.S. Nuclear Regulatory Commission Page 2

  • provides the existing TS Bases pages marked up to show the proposed changes and is provided for information only.

The proposed change has been reviewed by the Plant Operations Review Committee in accordance with the requirements of the CEG Quality Assurance Program.

CEG requests approval of the proposed change by March 20, 2026. Once approved, the amendment will be implemented within 60 days. This implementation period will provide adequate time for the affected station documents to be revised using the appropriate change control mechanisms.

In accordance with 10 CFR 50.91, "Notice for public comment; State consultation,"

paragraph (a)(1), the analysis about the issue of no significant hazards consideration using the standards in 10 CFR 50.92 is being provided to the Commission.

In accordance with 10 CFR 50.91, "Notice for public comment; State consultation,"

paragraph (b), CEG is notifying the State of Illinois of this application for license amendment by transmitting a copy of this letter and its attachments to the designated State Official.

There are no regulatory commitments contained in this letter. Should you have any questions concerning this letter, please contact Mr. Kenneth M. Nicely at (779) 231-6119.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 20th day of June 2025.

Respectfully, Mark Humphrey Sr. Manager Licensing Constellation Energy Generation, LLC Attachments:

1. Description and Assessment
2. Proposed Technical Specification and Operating License Changes (Mark-Up)
3. Proposed Technical Specification Bases Changes (Mark-Up) - For Information Only

Enclosures:

1. List of Revised Required Actions to Corresponding PRA Functions
2. (Not Used)
3. (Not Used)
4. (Not Used)
5. Baseline Core Damage Frequency (CDF) and Large Early Release Frequency (LERF)
6. (Not Used)
7. (Not Used)
Humphrey, Mark D.

Digitally signed by Humphrey, Mark D.

Date: 2025.06.20 12:19:56

-05'00'

June 20, 2025 U.S. Nuclear Regulatory Commission Page 3

8. (Not Used)
9. (Not Used)
10. (Not Used)
11. (Not Used)
12. Risk Management Action Examples cc:

NRC Regional Administrator, Region III NRC Senior Resident Inspector - QCNPS Illinois Emergency Management Agency - Division of Nuclear Safety

ATTACHMENT 1 Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265 License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray Description and Assessment

ATTACHMENT 1 Description and Assessment Page 1

1.0 DESCRIPTION

The proposed amendment would modify the Quad Cities Nuclear Power Station (QCNPS),

Units 1 and 2, Technical Specification (TS) requirements related to Completion Times (CTs) for Required Actions to provide the option to calculate a longer, risk-informed CT (RICT).

Specifically, the proposed amendment modifies TS 3.6.2.4, "Residual Heat Removal (RHR)

Suppression Pool Spray," to permit the use of RICT for the condition of one RHR suppression pool spray subsystem inoperable. The proposed change also modifies the Operating Licenses for QCNPS, Units 1 and 2, to remove license conditions associated with one-time actions that were added to the Operating Licenses in Reference 1 to support the initial implementation of the Risk Informed Completion Time Program.

The methodology for using the RICT Program is described in NEI 06-09-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS)

Guidelines," Revision 0, which was approved by the NRC on May 17, 2007. Adherence to NEI 06-09-A is required by the RICT Program.

The proposed amendment is consistent with TSTF-505, Revision 2, "Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b."

2.0 ASSESSMENT

2.1 Applicability of Published Safety Evaluation In Amendment Nos. 302 and 298 for QCNPS, Units 1 and 2 (i.e., Reference 1), respectively, the NRC approved adoption of TSTF 505, Revision 2, "Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b." TSTF-505 modifies NUREG-1433, "Standard Technical Specifications, General Electric BWR/4 Plants," TS 3.6.2.4 to permit the use of RICT for the condition of one RHR suppression pool spray subsystem inoperable.

The change to TS 3.6.2.4 was not adopted for QCNPS as part of Reference 1 because at that time, the suppression pool spray function was not modeled in the probabilistic risk assessment (PRA). Although the suppression pool spray function is not explicitly modeled in the PRA, a RICT can be quantitatively calculated for TS Required Action 3.6.2.4.A.1 using surrogate basic events to represent a bounding unavailability of drywell spray. Therefore, the failure of the drywell spray function can be used as a conservative surrogate since this bounds the risk of the suppression pool spray function. As such, the use of RICT for the condition of one RHR suppression pool spray subsystem inoperable is consistent with TSTF-505.

CEG has reviewed TSTF-505, Revision 2, and the model safety evaluation dated November 21, 2018 (ADAMS Accession No. ML18267A259). This review included the information provided to support TSTF-505 and the safety evaluation for NEI 06-09-A. As described in the subsequent paragraphs, CEG has concluded that the technical basis is applicable to QCNPS, Units 1 and 2, and support incorporation of this amendment in the QCNPS TS.

ATTACHMENT 1 Description and Assessment Page 2 2.2 Verifications and Regulatory Commitments In accordance with Section 4.0, Limitations and Conditions, of the safety evaluation for NEI 06-09-A, the following is provided:

1. Enclosure 1 identifies each of the TS Required Actions to which the RICT Program will apply, with a comparison of the TS functions to the functions modeled in the probabilistic risk assessment (PRA) of the structures, systems and components (SSCs) subject to those actions.
2. Enclosure 2 is not included and is not applicable. The QCNPS RICT license amendment request (i.e., Reference 2) utilized Application Specific Models (ASMs) that have since been superseded by new Models of Record (MORs). However, neither the addition of TS Required Action 3.6.2.4.A.1 nor the new MORs change the technical acceptability conclusions as provided in the Reference 2 submittal as there have been no PRA upgrades or newly developed methods incorporated into these new MORs.

Specific differences between the ASMs used in Reference 2 and the MORs used in this application are discussed in Enclosure 5 of this application.

3. Enclosure 3 is not applicable since each PRA model used for the RICT Program is addressed using a standard endorsed by the NRC.
4. Enclosure 4 is not included because the addition of TS Required Action 3.6.2.4.A.1 does not change any conclusions or justifications for excluding sources of risk not addressed by the PRA models since the original Reference 2 submittal.
5. Enclosure 5 provides the plant-specific baseline core damage frequency (CDF) and large early release frequency (LERF) to confirm that the potential risk increases allowed under the RICT Program are acceptable.
6. Enclosure 6 is not applicable since the RICT Program is not being applied to shutdown modes.
7. Enclosure 7 is not included because the PRA model update process remains unchanged from the process reviewed by the NRC as part of the original RICT license amendment request (i.e., Reference 2).
8. Enclosure 8 is not included because the Real Time Risk (RTR) tool that assesses real-time configuration risk remains unchanged from the tool reviewed by the NRC as part of the original RICT license amendment request (i.e., Reference 2).
9. Enclosure 9 is not included because the addition of TS 3.6.2.4.A to the QCNPS RICT Program does not affect any of the key assumptions and sources of uncertainty in the PRA models provided in Enclosure 9 of the original RICT license amendment request (i.e., Reference 2).
10. Enclosure 10 is not included because the addition of TS 3.6.2.4.A to the QCNPS RICT Program does not affect the description of the implementing programs and procedures

ATTACHMENT 1 Description and Assessment Page 3 regarding the plant staff responsibilities for the RICT Program implementation, including risk management action (RMA) implementation, that were discussed in the original RICT license amendment request (i.e., Reference 2).

11. Enclosure 11 is not included because the addition of TS 3.6.2.4.A to the QCNPS RICT Program does not change the description of the implementation and monitoring program as described in Enclosure 11 of the original RICT license amendment request (i.e.,

Reference 2).

12. Enclosure 12 provides example Risk Management Actions (RMAs) that have been created to explicitly address TS 3.6.2.4.A.

2.3 Optional Variations The QCNPS, Units 1 and 2, Operating Licenses contain a condition that states:

Adoption of Risk Informed Completion Times TSTF-505, Revision 2, "Provide Risk-Informed Extension Completion Times - RITSTF Initiative 4b" Constellation is approved to implement TSTF-505, Revision 2, modifying the Technical Specifications requirements related to Completion Times (CT) for Required Actions to provide the option to calculate a longer, risk-informed CT (RICT). The methodology for using the new Risk Informed Completion Time Program is described in NEI 06-09-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines,"

Revision 0, which was approved by the NRC on May 17, 2007.

Constellation will complete the implementation items listed in Attachment 5 of Constellation Letter to the NRC dated June 8, 2023, as modified by Constellation Letter dated March 19, 2024, prior to implementation of the RICT Program. All issues identified in Attachment 5 of Constellation Letter to the NRC dated June 8, 2023, as modified by Constellation Letter dated March 19, 2024, will be addressed and any associated changes will be made, focused-scope peer reviews will be performed on changes that are PRA upgrades as defined in the PRA standard (ASME/ANS RA-Sa-2009, as endorsed by RG 1.200, Revision 2),

and any findings will be resolved and reflected in the PRA of record prior to the implementation of the RICT Program.

The purpose of this license condition, as discussed in the NRC safety evaluation for the Reference 1 amendments, is to explicitly state that prior to implementation, the QCNPS RICT Program and PRAs will: (1) be consistent with NEI 06-09-A, and (2) address all changes consistent with RG 1.200, Revision 2. The proposed change removes this license condition from the QCNPS, Units 1 and 2, Operating Licenses for the following reasons.

1. The first paragraph of the license condition serves the same purpose as TS Section 5.5.15, which states "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) Guidelines."

ATTACHMENT 1 Description and Assessment Page 4 Therefore, the QCNPS RICT Program will remain consistent with NEI 06-09-A, and any change to the RICT Program that deviates from NEI 06-09-A would require NRC review and approval via a license amendment.

2. The second paragraph of the license condition is not needed since, because the RICT Program has already been implemented at QCNPS, the implementation items are no longer relevant. As noted in Reference 3, the implementation items listed in modified Table A5-1 superseded the originally submitted Table A5-1 in its entirety. Four implementation items are discussed in Reference 3, Attachment 4, modified Table A5-1, and their resolutions are summarized below.

Description Implementation Item Status/Reference PRA Model Upgrade (Y/N),

FSPR and F&O Closure Results (if needed)

TS 3.6.1.7.A: One or more lines with one reactor building-to-suppression chamber vacuum breaker not closed.

The structures, systems, and components (SSCs) are not modeled.

The model will be updated to include these SSCs prior to exercising the RICT Program for this TS.

The internal events and fire PRA models were updated to add explicit modeling of the reactor building-to-suppression chamber vacuum breakers.

QC-PSA-014 Rev. 6 - QC PRA Quantification Notebook QC-PSA-021.61 Rev. 3 - QC Fire PRA Summary and Quantification Notebook N - This change is not identified as a PRA Model Upgrade and therefore a Focused Scope Peer Review was not required.

TS 3.6.1.7.C:

One line with one or more reactor building-to-suppression chamber vacuum breakers inoperable for opening.

The SSCs are not modeled. The model will be updated to include these SSCs prior to exercising the RICT Program for this TS.

The internal events and fire PRA models were updated to add explicit modeling of the reactor building-to-suppression chamber vacuum breakers.

QC-PSA-014 Rev. 6 - QC PRA Quantification Notebook QC-PSA-021.61 Rev. 3 - QC Fire PRA Summary and Quantification Notebook N - This change is not identified as a PRA Model Upgrade and therefore a Focused Scope Peer Review was not required.

TS 3.6.1.7.E: Two lines with one reactor building-to-suppression chamber vacuum breakers inoperable for opening.

The SSCs are not modeled. The model will be updated to include these SSCs prior to exercising the RICT Program for this TS.

The internal events and fire PRA models were updated to add explicit modeling of the reactor building-to-suppression chamber vacuum breakers.

QC-PSA-014 Rev. 6 - QC PRA Quantification Notebook QC-PSA-021.61 Rev. 3 - QC Fire PRA Summary and Quantification Notebook N - This change is not identified as a PRA Model Upgrade and therefore a Focused Scope Peer Review was not required.

ATTACHMENT 1 Description and Assessment Page 5 Description Implementation Item Status/Reference PRA Model Upgrade (Y/N),

FSPR and F&O Closure Results (if needed)

LIP Flood Barrier Upgrades and Deployment: LIP barriers are modified to protect the plant up to 599.0'.

Complete EC 636914, Update to LIP Barriers to Assist the Station External Flood, and EC 636912, Update to Station External Flood Response in Support of Risk Reduction, modifications (scope includes both physical plant and documentation /

procedure changes).

  • Installed modification EC 636914 for LIP barriers for external flood response
  • Installed modification EC 639234 for a cover plate reinforcement in the RW basement area
  • Completed EC 636912 to update station external flood response in support of risk reduction
  • Training on the new external flood response was completed with Operations staff
  • Procedures QCOA 0010-16, Flood Emergency, and QCOA 0010-22, Local Intense Precipitation Response, were revised to add new external flood response actions
  • Updated UFSAR Section 3.4 to revise external flood response information Not applicable since these were not modeling items. Evidence of their completion is provided in the previous column.

CEG has reviewed this change and determined that it does not affect the applicability of TSTF-505, Revision 2, to the QCNPS TS.

3.0 REGULATORY SAFETY ANALYSIS 3.1 No Significant Hazards Consideration Analysis Constellation Energy Generation, LLC (CEG) has evaluated the proposed change to the Technical Specifications (TS) and Operating Licenses using the criteria in 10 CFR 50.92 and has determined that the proposed change does not involve a significant hazards consideration.

CEG requests an amendment to modify the Quad Cities Nuclear Power Station (QCNPS),

Units 1 and 2, TS requirements related to Completion Times (CTs) for Required Actions to provide the option to calculate a longer, risk-informed CT (RICT). Specifically, the proposed amendment modifies TS 3.6.2.4, "Residual Heat Removal (RHR) Suppression Pool Spray," to permit the use of RICT for the condition of one RHR suppression pool spray subsystem inoperable. The proposed change also modifies the Operating Licenses for QCNPS, Units 1 and 2, to remove license conditions associated with one-time actions that were added to the Operating Licenses to support the initial implementation of the Risk Informed Completion Time Program.

As required by 10 CFR 50.91(a), an analysis of the issue of no significant hazards consideration is presented below:

ATTACHMENT 1 Description and Assessment Page 6

1.

Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No The proposed change permits the extension of CTs provided the associated risk is assessed and managed in accordance with the NRC approved RICT Program. The proposed change also deletes license conditions associated with one-time actions that have already been completed. The proposed change does not involve a significant increase in the probability of an accident previously evaluated because the change involves no change to the plant or its modes of operation. The proposed change does not increase the consequences of an accident because the design-basis mitigation function of the affected systems is not changed and the consequences of an accident during the extended CT are no different from those during the existing CT.

Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2.

Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No The proposed change does not change the design, configuration, or method of operation of the plant. The proposed change does not involve a physical alteration of the plant (no new or different kind of equipment will be installed).

Therefore, the proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

3.

Does the proposed change involve a significant reduction in a margin of safety?

Response: No The proposed change permits the extension of CTs provided risk is assessed and managed in accordance with the NRC approved RICT Program. The proposed change also deletes license conditions associated with one-time actions that have already been completed. The proposed change utilizes a previously-approved and implemented risk-informed configuration management program to assure that adequate margins of safety are maintained.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, CEG concludes that the proposed change presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.

ATTACHMENT 1 Description and Assessment Page 7 3.2 Conclusions In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

4.0 ENVIRONMENTAL CONSIDERATION

The proposed change would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed change does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed change meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9).

Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed change.

5.0 REFERENCES

1.

Letter from R. Kuntz (U.S. NRC) to D. P. Rhoades (Constellation Energy Generation, LLC), "Quad Cities Nuclear Power Station, Units 1 and 2 - Issuance of Amendment Nos. 302 and 298 Re: Adoption of TSTF 505, 'Provide Risk Informed Extended Completion Times - RITSTF Initiative 4B' and TSTF 591 'Revise Risk Informed Completion Time (RICT) Program' (EPID L-2023-LLA-0084)," dated August 8, 2024 (ADAMS Accession No. ML24183A108)

2.

Letter from P. R. Simpson (Constellation Energy Generation, LLC) to U.S. NRC, "License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, 'Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b," dated June 8, 2023 (ADAMS Accession No. ML23159A249)

3.

Letter from M. Humphrey (Constellation Energy Generation, LLC) to U.S. NRC, "Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, 'Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b'," dated March 19, 2024 (ADAMS Accession No. ML24079A122)

ATTACHMENT 2 Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265 License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray Proposed Technical Specification and Operating License Changes (Mark-Up)

Renewed Facility Operating License No. DPR-29 Page 10 Page 11 Renewed Facility Operating License No. DPR-30 Page 10 Page 11 Technical Specifications Page 3.6.2.4-1 Renewed License No. DPR-29 Amendment No. 302 (4)

Ensure that if any inserts are identified as potentially failing the minimum certified Boron-10 areal density criterion, based on correlation of the coupon evaluation or insert service wear evaluation results to inserts, or other abnormal indications, Constellation Energy Generation, LLC will take affected inserts out of service until it can be positively demonstrated that the minimum certified Boron-10 areal density criterion (0.0116 g/cm2) is met for each insert; and, (5)

Submit a report to the NRC, within 90 days following completion of evaluations associated with Item 4 above, that describes the testing results, assessments performed, and interim and long-term corrective actions for abnormal indications.

CC.

Constellation Energy Generation, LLC is approved to implement 10 CFR 50.69 using the processes for categorization of Risk-Informed Safety Class (RISC)-1, RISC-2, RISC-3, and RISC-4 structures, systems, and components (SSCs) using: Probabilistic Risk Assessment (PRA) models to evaluate risk associated with internal events, including internal flooding, and internal fire; the shutdown safety assessment process to assess shutdown risk; the Arkansas Nuclear One, Unit 2 (ANO-2) passive categorization method to assess passive component risk for Class 2 and Class 3 and non-Class SSCs and their associated supports; the results of the non-PRA evaluations that are based on the IPEEE Screening Assessment for External Hazards updated using the external hazard screening significance process identified in ASME/ANS PRA Standard RA-Sa-2009 for other external hazards except seismic; and the alternative seismic approach as described in Constellation's submittal letter dated June 8, 2023, and all its subsequent associated supplements as specified in License Amendment No. 301 dated July 3, 2024 Prior NRC approval, under 10 CFR 50.90, is required for a change to the categorization process specified above (e.g., change from a seismic margins approach to a seismic probabilistic risk assessment approach).

DD.

Adoption of Risk Informed Completion Times TSTF-505, Revision 2, "Provide Risk-Informed Extension Completion Times - RITSTF Initiative 4b" Constellation is approved to implement TSTF-505, Revision 2, modifying the Technical Specifications requirements related to Completion Times (CT) for Required Actions to provide the option to calculate a longer, risk-informed CT (RICT). The methodology for using the new Risk Informed Completion Time Program is described in NEI 06-09-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines,"

Revision 0, which was approved by the NRC on May 17, 2007.

Constellation will complete the implementation items listed in Attachment 5 of Constellation Letter to the NRC dated June 8, 2023, as modified by Constellation Letter dated March 19, 2024, prior to implementation of the RICT Program. All issues identified in Attachment 5 of Constellation Letter to the NRC dated June 8, 2023, as modified by Constellation Letter dated March 19, 2024, will be addressed and any associated changes will be made, focused-scope peer reviews will be performed on changes that are PRA upgrades as defined in the Deleted Renewed License No. DPR-29 Amendment No. 302 PRA standard (ASME/ANS RA-Sa-2009, as endorsed by RG 1.200, Revision 2),

and any findings will be resolved and reflected in the PRA of record prior to the implementation of the RICT Program.

4.

This renewed operating license is effective as of the date of issuance and shall expire at midnight on December 14, 2032.

FOR THE NUCLEAR REGULATORY COMMISSION Original Signed By:

J. E. Dyer, Director Office of Nuclear Reactor Regulation Attachments:

1. Appendix A - Technical Specifications
2. Appendix B - Environmental Protection Plan Date of Issuance: October 28, 2004 Renewed License No. DPR-30 Amendment No. 298 (4)

Ensure that if any inserts are identified as potentially failing the minimum certified Boron-10 areal density criterion, based on correlation of the coupon evaluation or insert service wear evaluation results to inserts, or other abnormal indications, Constellation Energy Generation, LLC will take affected inserts out of service until it can be positively demonstrated that the minimum certified Boron-10 areal density criterion (0.0116 g/cm2) is met for each insert; and, (5)

Submit a report to the NRC, within 90 days following completion of evaluations associated with Item 4 above, that describes the testing results, assessments performed, and interim and long-term corrective actions for abnormal indications.

BB.

Constellation Energy Generation, LLC is approved to implement 10 CFR 50.69 using the processes for categorization of Risk-Informed Safety Class (RISC)-1, RISC-2, RISC-3, and RISC-4 structures, systems, and components (SSCs) using: Probabilistic Risk Assessment (PRA) models to evaluate risk associated with internal events, including internal flooding, and internal fire; the shutdown safety assessment process to assess shutdown risk; the Arkansas Nuclear One, Unit 2 (ANO-2) passive categorization method to assess passive component risk for Class 2 and Class 3 and non-Class SSCs and their associated supports; the results of the non-PRA evaluations that are based on the IPEEE Screening Assessment for External Hazards updated using the external hazard screening significance process identified in ASME/ANS PRA Standard RA-Sa-2009 for other external hazards except seismic; and the alternative seismic approach as described in Constellation's submittal letter dated June 8, 2023, and all its subsequent associated supplements as specified in License Amendment No. 297 dated July 3, 2024.

Prior NRC approval, under 10 CFR 50.90, is required for a change to the categorization process specified above (e.g., change from a seismic margins approach to a seismic probabilistic risk assessment approach).

CC.

Adoption of Risk Informed Completion Times TSTF-505, Revision 2, "Provide Risk-Informed Extension Completion Times - RITSTF Initiative 4b" Constellation is approved to implement TSTF-505, Revision 2, modifying the Technical Specifications requirements related to Completion Times (CT) for Required Actions to provide the option to calculate a longer, risk-informed CT (RICT). The methodology for using the new Risk Informed Completion Time Program is described in NEI 06-09-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines,"

Revision 0, which was approved by the NRC on May 17, 2007.

Constellation will complete the implementation items listed in Attachment 5 of Constellation Letter to the NRC dated June 8, 2023, as modified by Constellation Letter dated March 19, 2024, prior to implementation of the RICT Program. All issues identified in Attachment 5 of Constellation Letter to the NRC dated June 8, 2023, as modified by Constellation Letter dated March 19, 2024, will be addressed and any associated changes will be made, focused-scope peer reviews will be performed on changes that are PRA upgrades as defined in the Deleted Renewed License No. DPR-30 Amendment No. 298 PRA standard (ASME/ANS RA-Sa-2009, as endorsed by RG 1.200, Revision 2),

and any findings will be resolved and reflected in the PRA of record prior to the implementation of the RICT Program.

4.

This renewed operating license is effective as of the date of issuance and shall expire at midnight on December 14, 2032.

FOR THE NUCLEAR REGULATORY COMMISSION Original Signed By:

J. E. Dyer, Director Office of Nuclear Reactor Regulation Attachments:

1. Appendix A - Technical Specifications
2. Appendix B - Environmental Protection Plan Date of Issuance: October 28, 2004

RHR Suppression Pool Spray 3.6.2.4 Quad Cities 1 and 2 3.6.2.4-1 Amendment No. 245/240 3.6 CONTAINMENT SYSTEMS 3.6.2.4 Residual Heat Removal (RHR) Suppression Pool Spray LCO 3.6.2.4 Two RHR suppression pool spray subsystems shall be OPERABLE.

APPLICABILITY:

MODES 1, 2, and 3.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

One RHR suppression pool spray subsystem inoperable.

A.1 Restore RHR suppression pool spray subsystem to OPERABLE status.

7 days B.

Two RHR suppression pool spray subsystems inoperable.

B.1 Restore one RHR suppression pool spray subsystem to OPERABLE status.

8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> C.

Required Action and associated Completion Time not met.

NOTE-----------

LCO 3.0.4.a is not applicable when entering MODE 3.

C.1 Be in MODE 3.

12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OR In accordance with the Risk Informed Completion Time Program

ATTACHMENT 3 Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265 License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray Proposed Technical Specification Bases Changes (Mark-Up) - For Information Only Technical Specifications Bases Page B 3.6.2.4-2

RHR Suppression Pool Spray B 3.6.2.4 Quad Cities 1 and 2 B 3.6.2.4-2 Revision 50 BASES (continued)

APPLICABLE Reference 1 contains the results of analyses used to predict SAFETY ANALYSES primary containment pressure and temperature following large and small break loss of coolant accidents. The intent of the analyses is to demonstrate that the pressure reduction capacity of the RHR Suppression Pool Spray System is adequate to maintain the primary containment conditions within design limits. The time history for primary containment pressure is calculated to demonstrate that the maximum pressure remains below the design limit.

The RHR Suppression Pool Spray System satisfies Criterion 3 of 10 CFR 50.36(c)(2)(ii).

LCO In the event of a DBA, a minimum of one RHR suppression pool spray subsystem is required to mitigate potential bypass leakage paths and maintain the primary containment peak pressure below the design limits (Ref. 1). To ensure that these requirements are met, two RHR suppression pool spray subsystems must be OPERABLE with power from two safety related independent power supplies. Therefore, in the event of an accident, at least one subsystem is OPERABLE assuming the worst case single active failure. An RHR suppression pool spray subsystem is OPERABLE when one of the pumps, the heat exchanger, and associated piping, valves, instrumentation, and controls are OPERABLE. Management of gas voids is important to RHR Suppression Pool Spray System OPERABILITY.

APPLICABILITY In MODES 1, 2, and 3, a DBA could cause pressurization of primary containment. In MODES 4 and 5, the probability and consequences of these events are reduced due to the pressure and temperature limitations in these MODES. Therefore, maintaining RHR suppression pool spray subsystems OPERABLE is not required in MODE 4 or 5.

ACTIONS A.1 With one RHR suppression pool spray subsystem inoperable, the inoperable subsystem must be restored to OPERABLE status within 7 days. In this condition, the remaining OPERABLE RHR suppression pool spray subsystem is adequate to perform the primary containment bypass leakage mitigation function.

(continued) or in accordance with the Risk Informed Completion Time Program

ENCLOSURE 1 Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265 License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray List of Revised Required Actions to Corresponding PRA Functions

License Amendment Request Adopt RICT for Suppression Pool Spray E1-1 List of Revised Required Actions to Corresponding PRA Functions

1. Introduction Section 4.0, Item 2 of the U.S. Nuclear Regulatory Commission (NRC) Final Safety Evaluation

[Ref. 1] for NEI 06-09, Revision 0-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines" [Ref. 2] identifies the following needed content:

The LAR will provide identification of the TS Limiting Conditions for Operation (LCOs) and action requirements to which the RMTS will apply.

The LAR will provide a comparison of the TS functions to the PRA modeled functions of the structures, systems, and components (SSCs) subject to those LCO actions.

The comparison should justify that the scope of the PRA model, including applicable success criteria such as number of SSCs required, flow rate, etc., are consistent with licensing basis assumptions (i.e., 50.46 Emergency Core Cooling System (ECCS) flowrates) for each of the TS requirements, or an appropriate disposition or programmatic restriction will be provided.

2. Revised Required Actions to Corresponding PRA Functions This enclosure provides confirmation that the Quad Cities Nuclear Power Station (QCNPS) PRA models include the necessary scope of SSCs and their functions to address each proposed application of the RICT Program to the proposed scope of the TS LCO Conditions.

Table E1-1 below lists the TS LCO 3.6.2.4.A Condition to which the RICT Program is proposed to be applied and documents the following information regarding the TS with the associated safety analyses, the analogous PRA functions, and the results of the comparison:

TS Condition: Lists the alphanumerical TS and Condition.

TS Condition

Description:

Lists the LCOs and Condition statements within the scope of the RICT Program.

SSCs Covered by TS LCO: Lists the SSCs addressed by each action requirement.

SSCs Modeled in PRA: Indicates whether the SSCs addressed by the TS LCO Condition are included in the PRA.

Function Covered by TS LCO: Summarizes the required functions from the design basis analyses.

Design Success Criteria: Summarizes the success criteria from the design basis analyses.

PRA Success Criteria: The function success criteria modeled in the PRA.

License Amendment Request Adopt RICT for Suppression Pool Spray E1-2 Other Comments: Provides the justification or resolution to address any inconsistencies between the TS and PRA functions regarding the scope of SSCs and the success criteria. Where the PRA scope of SSCs is not consistent with the TS, additional information is provided to describe how the LCO Condition can be evaluated using appropriate surrogate events. Differences in the success criteria for TS functions are addressed to demonstrate the PRA criteria provide a realistic estimate of the risk of the TS Condition as required by NEI 06-09, Revision 0-A.

The corresponding SSCs for the TS LCO and the associated TS function is identified and compared to the PRA. This description also includes the design success criteria and the applicable PRA success criteria. Any differences between the scope or success criteria are described in Table E1-1. Scope differences are justified by identifying appropriate surrogate events which permit a risk evaluation to be completed using the Real-Time Risk (RTR) tool for the RICT Program. Differences in success criteria typically arise due to the requirement in the PRA standard to make PRAs realistic rather than bounding, whereas design basis criteria are necessarily conservative and bounding. The use of realistic success criteria is necessary to conform to capability Category II of the PRA standard [Ref. 3] as required by NEI 06-09, Revision 0-A.

License Amendment Request Adopt RICT for Suppression Pool Spray E1-3 Table E1-1: TS 3.6.2.4.A to Corresponding PRA Function TS Condition TS Condition Description SSCs Covered by TS LCO SSCs Modeled in PRA?

Function Covered by TS LCO Design Success Criteria PRA Success Criteria Other Comments 3.6.2.4.A One RHR suppression pool spray (SPS) subsystem inoperable.

Two SPS subsystems Not explicitly Suppression pool pressure and temperature control One pump, heat exchanger, and associated piping in one of two subsystems Same as Design Success Criteria The SPS function is not explicitly modeled in the PRA.

The failure of the drywell spray function is used as a conservative surrogate since this bounds the risk of SPS function.

License Amendment Request Adopt RICT for Suppression Pool Spray E1-4

3. Example RICT Calculation An example of the calculated RICT is provided in Table E1-2 for TS 3.6.2.4.A (assuming no other SSCs modeled in the PRA are unavailable). Following inclusion of this TS into the scope of RICT, the actual RICT value will be calculated using the actual plant configuration and the current revision of the PRA models representing the as-built, as-operated condition of the plant, as required by NEI 06-09, Revision 0-A and the NRC safety evaluation, and may differ from the RICT presented in Table E1-2.

Table E1-2 below lists the calculated RICT for the TS condition using the method outlined in NEI 06-09, Revision 0-A [Ref. 2]. The same equation was used to calculate the Large Early Release Frequency (LERF) RICT by simply using the RICT Incremental Conditional Large Early Release Probability (ICLERP) Limit and LERF instead.

=

1

x 365 The RICT Incremental Conditional Core Damage Probability (ICCDP) limit is 1.00E-05, while the RICT ICLERP limit is 1.00E-06. The RICTs are limited to a maximum of thirty (30) days, and to a minimum of the original TS completion time.

Table E1-2 provides the example RICT calculation for TS 3.6.2.4.A, with the full calculation documented in Section 4 of this enclosure.

Table E1-2: TS 3.6.2.4.A RICT Estimate TS LCO Condition RICT Estimate 3.6.2.4.A Suppression Pool Spray (SPS) System - One RHR suppression pool spray (SPS) subsystem inoperable.

30.01,2 Table E1-2 Notes:

1. RICT estimate is based on the Unit 1 internal events and internal fire PRA model calculations with seismic and high winds Core Damage Frequency (CDF) and LERF penalties. RICTs calculated to be greater than 30 days are capped at 30 days based on NEI 06-09-A. RICTs are rounded to nearest tenth of a day.
2. Per NEI 06-09, for cases where the total CDF or LERF is greater than 1E-03/yr or 1E-04/yr, respectively, the RICT Program will not be entered.

License Amendment Request Adopt RICT for Suppression Pool Spray E1-5

4. Estimated RICT Calculation

4.1 Purpose and Scope

The purpose of this section is to calculate the RICT estimate for TS 3.6.2.4 Condition A, "One RHR Suppression Pool Spray Subsystem Inoperable." The methodology used, model files, and results are included or referenced in this analysis. These results demonstrate the PRA models' capability to calculate a representative RICT for this specific case and TS, but the real RICT value will change based on the actual plant configuration.

4.2 Model Files The Quad Cities Nuclear Power Station FPIE PRA model used in this evaluation is FPIE MOR, QC123A [Ref. 4]. The FPRA model used in this evaluation is Fire PRA MOR, QC123AF [Ref. 5].

Table E1-3 below provides a description of all the quantification files involved with this calculation.

Table E1-3: List of Quantification and Data Files Used for RICT Estimate of TS 3.6.2.4.A File Name Description QC123A.caf This is the merged CDF and LERF single top fault tree model used as the master fault tree for quantification of the Internal Events model.

QC123A - Availability 1.rr This is the PRA database for the model used for quantification of the Internal Events model. It has been modified to set the criticality factor to 1.

Q1MEX23A.txt This is the mutually exclusive file used during quantification of the Internal Events model.

QCFLG23A.flg This is the master flag file used for quantification of the Internal Events model.

QC123A-RCV.recv This is the recovery file used during quantification of the Internal Events model.

QC123A.qnt This is the PRAQuant file used to set up and run the Zero-Maintenance Internal Events model for all quantification cases (base cases and RICT estimates).

QC123AF-1TOP This is the merged CDF and LERF single top fault tree model used as the master fault tree for quantification of the optimized Fire model.

QC123AF - Availability 1.rr This is the PRA database for the model used for quantification of the optimized Fire model. It has been modified to set the criticality factor to 1.

Q1MEX23A.txt This is the mutually exclusive file used during quantification of the Fire model.

License Amendment Request Adopt RICT for Suppression Pool Spray E1-6 File Name Description Q123AF-FLG.flg This is the master flag file used for quantification of the Fire model.

QC123AF-POST-PROCESS.recv This is the recovery file used during quantification of the Fire model. It is applied to each individual case to specify the order in which the post-processing recovery files are applied after FTREX 2.0 cutset recovery.

QC123AF-RCV.recv An additional recovery file called by QC123AF-POST-PROCESS.recv to assist in post-processing.

QC123AF-RCV-BROWSE.recv An additional recovery file called by QC123AF-POST-PROCESS.recv to assist in post-processing.

QC123AF-RCV-FORMATCS.recv An additional recovery file called by QC123AF-POST-PROCESS.recv to assist in post-processing.

QC123AF.qnt This is the PRAQuant file used to set up and run the Zero-Maintenance Fire model for all quantification cases (base cases and RICT estimates).

ZTM.flg This is the flag file used to set the base cases to the Zero-Maintenance configuration settings for RICT comparison values.

3.6.2.4.A_1.flg Flag file for TS 3.6.2.4.A Case 1 - DW Spray Isolation Valve -26A FTO & ZTM 3.6.2.4.A_2.flg Flag file for TS 3.6.2.4.A Case 2 - DW Spray Isolation Valve -26B FTO & ZTM QC-LAR-013 Worksheet.xlsx This is the spreadsheet used to store the results and calculate the RICT estimates for FPIE and Fire.

4.3 Calculations The FPIE and Fire calculations for this application use several specific assumptions and settings:

Unit availability is set to 1.0 by adjusting the criticality factor Type Code (@CRIT-FACTOR) to 1.0 for FPIE and Fire in the.RR Database.

The average Unit Service Water configuration is assumed; therefore, no Service Water flag is set to True or 1.0.

Maintenance unavailability terms are set to False, unless unavailable due to the configuration.

4.3.1 Quantification Truncation The FPIE Zero-Maintenance model (also referred to as the "base case") is quantified at a truncation of 1.00E-12 for CDF and 1.00E-12 for LERF. The FPRA Zero-Maintenance model is quantified at a truncation of 1.00E-11 for CDF and 1.00E-12 LERF. The truncation limits for both

License Amendment Request Adopt RICT for Suppression Pool Spray E1-7 models are based on the convergent truncations determined for each model as documented in the respective Summary Notebook [Refs. 4 and 5].

The delta () CDF and LERF (or CDF and LERF) are calculated for the base case and the TS-specific cases as part of the RICT estimate calculation. The base case CDF or LERF truncation limits are also used for the TS Allowed Outage Time (AOT) cases.

Table E1-4: Base Case CDF and LERF Results (Zero-Maintenance)

Model CDF LERF FPIE QC123A 1.51E-06 1.34E-07 FPRA QC123AF 1.21E-05 1.95E-06 4.3.2 Basic Event Selection and Quantification Flag Files A case-specific flag file is created to represent the TS 3.6.2.4.A out-of-service condition.

Because TS 3.6.2.4.A is not explicitly modeled, surrogate basic events are used to represent a bounding unavailability of the Drywell Spray. This is identical to the flag files created to represent TS 3.6.2.6.A as part of the original LAR submittal. Two flag files are created to model the unavailability of each Drywell Spray train by way of the isolation valve failing to open. These flag files also set all Maintenance basic events to false and are used for both the FPIE and FPRA models. These files are included in the electronic calculation data file listed on the signature page.

4.3.3 FPIE and FPRA Results The CDF and LERF results, as well as the CDF and LERF (difference between case-specific frequency and base frequency) and Total CDF and LERF, are shown in Table E1-5 as well as the sheets of the "QC-LAR-013 Worksheet.xlsx" file listed in Table E1-3. Only the lowest RICT case for each TS is shown in Table E1-5, the full results table with every case can be found in the electronic file. It should be noted that the CDF and LERF values reported are the "Unfactored" results from the CAFTA Cutset Editor (CAFTA 6.0 and later).

Table E1-5: CDF and LERF Calculation Results TS FPIE CDF FPIE LERF FIRE CDF FIRE LERF CDF FPIE CDF FIRE CDF TOTAL LERF FPIE LERF FIRE LERF TOTAL 3.6.2.4.A 1.51E-06 1.34E-07 1.18E-05 2.21E-06 1.68E-09 0.00E+00 1.43E-05 2.00E-12 2.57E-07 2.74E-06 4.3.4 Contribution from Seismic Estimates of Seismic CDF (SCDF) SCDF and Seismic LERF (SLERF) are derived for use in the QCNPS TSTF-505 program in the External Hazards Assessment [Ref. 6]. The SLERF risk contribution to a RICT depends on whether containment is inerted or de-inerted. Although both

License Amendment Request Adopt RICT for Suppression Pool Spray E1-8 inerted and de-inerted penalty values are shown in Table E1-6, the normal operating state is with containment inerted, and the example RICT in this application uses the containment inerted penalty values.

Table E1-6: Seismic Results Containment CDF (/yr)

LERF

(/yr)

Inerted 4.31E-06 1.98E-06 De-Inerted 4.31E-06 The SCDF and SLERF inerted values shown in Table E1-6 are added to the Total CDF and LERF shown in Table E1-5, respectively.

4.3.5 Contribution from High Winds Estimates of High Winds CDF and LERF are derived for use in the QCNPS TSTF-505 program in the External Hazards Assessment [Ref. 6]. The example RICT in this application uses the penalty values, shown in Table E1-7.

Table E1-7: High Winds Results CDF (/yr) 1.00E-05 LERF (/yr) 5.00E-07 The High Winds CDF and LERF values shown in Table E1-7 are added to the Total CDF and LERF shown in Table E1-5, respectively.

4.3.6 RICT Calculations and Results Table E1-8 lists the calculated RICT for TS 3.6.2.4.A using the method outlined in NEI 06-09-A

[Ref. 2]. The same equation was used to calculate the LERF RICT by simply using the RICT LERF limit and LERF instead. The RICT CDF limit is 1.00E-05, while the RICT LERF limit is 1.00E-06. The RICTs are limited to a maximum of thirty (30) days, and to a minimum of the original TS completion time. The final RICT result is shown in Table E1-8, along with the TS condition as it appears in Section 3 of this enclosure. QC-LAR-013 Worksheet.xlsx in the electronic data file contains the results table with more detail into the calculations.

License Amendment Request Adopt RICT for Suppression Pool Spray E1-9 Table E1-8: TS 3.6.2.4.A RICT Estimate TS LCO Condition RICT Estimate 3.6.2.4.A Suppression Pool Spray (SPS) System - One RHR suppression pool spray (SPS) subsystem inoperable.

30.01,2 Table E1-8 Notes:

1. RICT estimate is based on the Unit 1 internal events and internal fire PRA model calculations with seismic and high winds CDF and large LERF penalties. RICTs calculated to be greater than 30 days are capped at 30 days based on NEI 06-09-A. RICTs are rounded to nearest tenth of a day.
2. Per NEI 06-09, for cases where the total CDF or LERF is greater than 1E-03/yr or 1E-04/yr, respectively, the RICT Program will not be entered.
5. References
1. Letter from Jennifer M. Golder (NRC) to Biff Bradley (NEI), "Final Safety Evaluation for Nuclear Energy Institute (NEI) Topical Report (TR) NEI 06-09, 'Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines',"

dated May 17, 2007 (ADAMS Accession No. ML071200238)

2. Nuclear Energy Institute (NEI) Topical Report (TR) NEI 06-09-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines,"

Revision 0, dated October 12, 2012 (ADAMS Accession No. ML12286A322)

3. ASME Standard ASME/ANS RA-Sa-2009, "Addenda to ASME/ANS RA-S-2008 Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications," dated February 2, 2009
4. QC-PSA-013, "Quad Cities PRA Summary Document Notebook," Revision 9, April 2024
5. QC-PRA-021.61, "Quad Cities Fire PRA Summary and Quantification Notebook,"

Revision 3, November 2024

6. QC-MISC-039, "External Hazards Assessment for Quad Cities Nuclear Power Plant,"

Revision 0, April 2023

ENCLOSURE 5 Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265 License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray Baseline Core Damage Frequency (CDF) and Large Early Release Frequency (LERF)

License Amendment Request Adopt RICT for Suppression Pool Spray E5-1 Baseline Core Damage Frequency (CDF) and Large Early Release Frequency (LERF)

1. Introduction Section 4.0, Item 6 of the U.S. NRC Final Safety Evaluation [Ref. 1] for NEI 06-09, Revision 0-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines" [Ref. 2], requires that the LAR provides the plant-specific total CDF and total LERF to confirm applicability of the limits of Regulatory Guide (RG) 1.174, Revision 1

[Ref. 3]. (Note that RG 1.174, Revision 3 [Ref. 4], issued by the NRC in January 2018, did not revise these limits.)

The purpose of Enclosure 5 is to demonstrate that the QCNPS total CDF and total LERF are below the guidelines established in RG 1.174. RG 1.174 does not establish firm limits for total CDF and LERF, but it recommends that risk-informed applications be implemented only when the total plant risk is no more than about 1E-4/year for CDF and 1E-5/year for LERF.

Demonstrating that these limits are met confirms that the risk metrics of NEI 06-09 can be applied to the QCNPS RICT Program.

2. Technical Approach The baseline CDF and LERF values provided in the initial LAR submittal were based on Application Specific Models (ASMs) for both FPIE and Fire that have since been superseded by new Full Power Internal Events (FPIE) and Fire PRA (FPRA) Models of Record (MORs) [Ref. 5 and 6]. Table E5-1 below provides the updated CDF and LERF values and includes an estimate of the seismic contribution to CDF and LERF using the same seismic penalty as documented in the External Hazards Assessment [Ref. 7] and as provided in the original LAR submittal1.

Similarly, the disposition of other external hazards remains below accepted screening criteria and therefore does not contribute significantly to the totals as reflected in the original LAR submittal [Ref. 7].

Table E5-1: Total Baseline CDF/LERF QCNPS Unit 1 Baseline CDF QCNPS Unit 1 Baseline LERF Source1 Contribution Source1 Contribution Internal Events PRA 1.8E-06 Internal Events PRA 1.4E-07 Fire PRA 1.4E-05 Fire PRA 2.2E-06 Seismic 4.3E-06 Seismic 2.0E-06 Other External Events No significant contribution Other External Events No significant contribution Total CDF 2.0E-05 Total LERF 4.4E-06 1 The seismic LERF penalty factor values listed in Table E5-1 are listed for the containment inerted (at-power) state. For further explanation on seismic penalties in inerted vs de-inerted states, consult Enclosure 4 [Ref. 8].

License Amendment Request Adopt RICT for Suppression Pool Spray E5-2 Table E5 1: Total Baseline CDF/LERF QCNPS Unit 2 Baseline CDF QCNPS Unit 2 Baseline LERF Source1 Contribution Source1 Contribution Internal Events PRA 1.8E-06 Internal Events PRA 1.4E-07 Fire PRA 1.6E-05 Fire PRA 2.5E-06 Seismic 4.3E-06 Seismic 2.0E-06 Other External Events No significant contribution Other External Events No significant contribution Total CDF 2.2E-05 Total LERF 4.6E-06 As demonstrated in Table E5-1, the total CDF and total LERF remain within the guidelines set forth in RG 1.174 and support small changes in risk that may occur during RICT entries.

Therefore, QCNPS TSTF-505 implementation is still consistent with NEI 06-09 guidance.

3. References
1. Letter from Jennifer M. Golder (NRC) to Biff Bradley (NEI), "Final Safety Evaluation for Nuclear Energy Institute (NEI) Topical Report (TR) NEI 06-09, 'Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines',"

dated May 17, 2007 (ADAMS Accession No. ML071200238)

2. Nuclear Energy Institute (NEI) Topical Report (TR) NEI 06-09-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines,"

Revision 0, dated October 12, 2012 (ADAMS Accession No. ML12286A322)

3. Regulatory Guide 1.174, "An Approach For Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis," Revision 1, dated November 2002 (ADAMS Accession No. ML023240437)
4. Regulatory Guide 1.174, "An Approach For Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis," Revision 3, dated January 2018 (ADAMS Accession No. ML17317A256)
5. QC-PSA-013, "Quad Cities PRA Summary Document Notebook," Revision 9, April 2024
6. QC-PRA-021.61, "Quad Cities Fire PRA Summary and Quantification Notebook,"

Revision 3, November 2024

7. QC-MISC-039, "External Hazards Assessment for Quad Cities Nuclear Power Plant,"

Revision 0, April 2023

8. RS-23-059, "License Amendment Request to Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, 'Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b'," June 8, 2023, ADAMS Accession No. ML23159A249

ENCLOSURE 12 Quad Cities Nuclear Power Station, Units 1 and 2 Renewed Facility Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265 License Amendment Request to Adopt Risk Informed Completion Time for Suppression Pool Spray Risk Management Action Examples

License Amendment Request 2 Adopt RICT for Suppression Pool Spray E12-1 Risk Management Action Examples

1. Introduction 2 describes the process for identification and implementation of Risk Management Actions (RMAs) applicable during extended Completion Times (CTs) and provides examples of RMAs. RMAs are governed by plant procedures for planning and scheduling maintenance activities. The procedures will provide guidance for the determination and implementation of RMAs when entering the RICT Program consistent with the guidance provided in NEI 06-09, Revision 0-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines" [Ref. 1].
2. Responsibilities For planned entries into the RICT Program, Work Management is responsible for developing the RMAs with assistance from Operations and Risk Management. Operations is responsible for approval and implementation of RMAs. For emergent entry into extended CTs, Operations is also responsible for developing the RMAs.
3. Procedural Guidance For planned maintenance activities, implementation of RMAs will be required if it is anticipated that the Risk Management Action Time (RMAT) will be exceeded. For emergent activities, RMAs must be implemented if the RMAT is reached. Also, if an emergent event occurs requiring recalculation of a RMAT already in place, the procedure will require a re-evaluation of the existing RMAs for the new plant configuration to determine if new RMAs are appropriate.

These requirements of the RICT Program are consistent with the guidance of NEI 06-09

[Ref. 1].

For emergent entry into a RICT, if the extent of condition is not known, RMAs related to the success of redundant and diverse SSCs and reducing the likelihood of initiating events relying on the affected function will be developed to address the increased likelihood of a common cause event.

RMAs will be implemented in accordance with current Constellation Energy Generation, LLC (CEG) procedures [Refs. 2, 3, 4, and 5] no later than the time at which an Incremental Core Damage Probability (ICDP) of 1E-6 is reached, or no later than the time when an Incremental Large Early Release Probability (ILERP) of 1E-7 is reached. If, as the result of an emergent condition, the Instantaneous Core Damage Frequency (ICDF) or the Instantaneous Large Early Release Frequency (ILERF) exceeds 1E-3 per year or 1E-4 per year, respectively, RMAs are also required to be implemented. These requirements are consistent with the guidelines of NEI 06-09 [Ref. 1].

License Amendment Request 2 Adopt RICT for Suppression Pool Spray E12-2 By determining which SSCs are most important from a CDF or LERF perspective for a specific plant configuration, RMAs may be created to protect these SSCs. Similarly, knowledge of the initiating event or sequence contribution to the configuration-specific CDF or LERF allows development of RMAs that enhance the capability to mitigate such events. The guidance in NUREG-1855, Revision 1, "Guidance on the Treatment of Uncertainties Associated with PRAs in Risk-Informed Decision Making," [Ref. 6] and the Electric Power Research Institute (EPRI) topical report (TR), TR-1026511, Revision 0, "Practical Guidance on the Use of Probabilistic Risk Assessment in Risk-Informed Applications with a Focus on the Treatment of Uncertainty,"

[Ref. 7] will be used in examining PRA results for significant contributors for the configuration, to aid in identifying appropriate compensatory measures (e.g., related to risk-significant systems that may provide diverse protection, or important support systems or human actions). of the original LAR identifies several areas of uncertainty in the internal events and fire PRAs that will be considered in defining configuration-specific RMAs when entering a RICT.

If the planned activity or emergent condition includes an SSC that is identified to impact fire PRA, as identified in the current Real-Time Risk Program, fire PRA specific RMAs associated with that SSC will be implemented per the current plant procedure.

It is possible to credit RMAs in RICT calculations, to the extent the associated plant equipment and operator actions are modeled in the PRA; however, such quantification of RMAs is neither required nor expected by NEI 06-09 [Ref. 1]. Nonetheless, if RMAs will be credited to determine RICTs, the procedure instructions will be consistent with the guidance in NEI 06-09 [Ref. 1].

NEI 06-09 [Ref. 1] classifies RMAs into the three categories described below:

1) Actions to increase risk awareness and control.

Shift brief Pre-job brief Training Presence of system engineer or other expertise related to the activity Special purpose procedure to identify risk sources and contingency plans

2) Actions to reduce the duration of maintenance activities.

Pre-staging materials Conducting training on mock-ups Performing the activity around the clock Performing walk-downs on the actual system(s) to be worked on prior to beginning work

3) Actions to minimize the magnitude of the risk increase.

Suspend or minimize activities on redundant systems Suspend or minimize activities on other systems that adversely affect the CDF or LERF

License Amendment Request 2 Adopt RICT for Suppression Pool Spray E12-3 Suspend or minimize activities on systems that may cause a trip or transient to minimize the likelihood of an initiating event that the out-of-service component is meant to mitigate Use temporary equipment to provide backup power, ventilation, etc.

Reschedule other risk-significant activities Determination of RMAs involves the use of both qualitative and quantitative considerations for the specific plant configuration and the practical means available to manage risk. The scope and number of RMAs developed and implemented are reached in a graded manner.

Procedural guidance for development of RMAs in support of the RICT Program builds off the RMAs developed for other processes, such as the RMAs developed under the 10 CFR 50.65(a)(4) program and the protected equipment program. Additionally, Common Cause RMAs are developed to address the potential impact of common cause failures.

General RMAs are developed for input into the RICT system guidelines. These guidelines are listed in site-specific Training & Reference Materials (T&RM) and are developed using a graded approach. Consideration is given for system functionality and includes consideration for common cause impacts within the system. These RMAs include:

Consideration of rescheduling maintenance to reduce risk Discussion of RICT in pre-job briefs Consideration of proactive return-to-service of other equipment Efficient execution of maintenance In addition to the RMAs developed qualitatively for the system guidelines, RMAs are developed based on the RTR tool to identify configuration-specific RMA candidates to manage the risk associated with internal events, internal flooding, and fire events. These actions include:

Identification of important equipment or trains for protection Identification of important operator actions for briefings Identification of key fire initiators and fire zones for RMAs in accordance with the site Fire RMA process Identification of dominant initiating events and actions to minimize potential for initiators Consideration of insights from PRA model cutsets, through comparison of importances Common cause RMAs are also developed to ensure availability of redundant SSCs, to ensure availability of diverse or alternate systems, to reduce the likelihood of initiating events that require operation of the out-of-service components, and to prepare plant personnel to respond to additional failures. Common cause RMAs are developed by considering the impact of loss of function for the affected SSCs.

License Amendment Request 2 Adopt RICT for Suppression Pool Spray E12-4 Examples of common cause RMAs include:

Performance of non-intrusive inspections on alternate trains Confidence runs performed for standby SSCs Increased monitoring for running components Expansion of monitoring for running components Deferring maintenance and testing activities that could generate an initiating event which would require operation of potentially affected SSCs Readiness of operators and maintenance to respond to additional failures Shift briefs or standing orders which focus on initiating event response or loss of potentially affected SSCs Per CEG procedures, for emergent conditions where the extent of condition is not performed prior to entering into the RMATs or the extent of condition cannot rule out the potential for common cause failure, common cause RMAs are expected to be implemented to mitigate common cause failure potential and impact. These can include the pre-identified RMAs included in the system guidelines as discussed above, as well as alternative common cause RMAs for the specific configuration. Alternate RMAs, including both regular and common cause considerations, are developed for the specific configuration following the steps outlined above.

4. Example RMAs Representative examples of RMAs that may be considered during a RICT Program entry to reduce the risk impact and ensure adequate defense-in-depth are provided below.

For TS 3.6.2.4.A, one RHR suppression pool spray (SPS) subsystem inoperable, additional RMAs would include:

1. Defer planned maintenance or testing activities on the redundant SPS subsystem, drywell subsystem, RHRSW subsystem, and associated support equipment. Treat those systems as protected equipment.
2. Defer planned maintenance or testing that affects the reliability of those safety systems that provide defense-in-depth, such as the drywell spray system. If testing or maintenance activities must occur, a review of the potential risk impact will be performed.
3. Minimize activities that could trip the unit.
4. Brief on system alignment of remaining SPS subsystem, including valve alignment.
5. Verify protected pathways.
6. Implement 10 CFR 50.65 (a)(4) fire-specific RMAs associated with the RHR subsystem.

License Amendment Request 2 Adopt RICT for Suppression Pool Spray E12-5

5. References
1. Nuclear Energy Institute (NEI) Topical Report (TR) NEI 06-09-A, "Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines,"

Revision 0, dated October 12, 2012 (ADAMS Accession No. ML12286A322)

2. OP-AA-201-012-1001, "Operations On-Line Fire Risk Management," Revision 5
3. OP-AA-108-118, "Risk Informed Completion Time," Revision 3
4. OP-AA-108-117, "Protected Equipment Program," Revision 7
5. WC-AA-101-1006, "On-Line Risk Management and Assessment," Revision 5
6. NUREG-1855, "Guidance on the Treatment of Uncertainties Associated with PRAs in Risk-Informed Decision Making," U.S. Nuclear Regulatory Commission, Revision 1, dated March 2017 (ADAMS Accession No. ML17062A466)
7. EPRI TR-1026511, "Practical Guidance on the Use of Probabilistic Risk Assessment in Risk-Informed Applications with a Focus on the Treatment of Uncertainty," dated December 2012 (publicly available at https://www.epri.com/research/products/000000000001026511)
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