Text

Modification to Technical Specification 2.6.1.3 Main Steam Line Isolation System Leakage Rate Surveillance Requirements
	ML25098A331
Person / Time
Site:	Susquehanna ; (NPF-014, NPF-022)
Issue date:	04/08/2025
From:	Casulli E; Susquehanna, Talen Energy
To:	; Office of Nuclear Reactor Regulation, Document Control Desk
References
	PLA-8164
	Download: ML25098A331 (1)
	v • d • e

Edward Casulli Susquehanna Nuclear, LLC SiteVicePresident 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.3795 Fax 570.542.1504 Edward.Casulli@TalenEnergy.com 10 CFR 50.90 Docket No. 50-387 and 50-388 Pursuant to 10 CFR 50.90, Susquehanna Nuclear, LLC (Susquehanna), is submitting a request for an amendment to the Technical Specifications (TS) for the Susquehanna Steam Electric Station (SSES), Units 1 and 2, Facility Operating License numbers NPF-14 and NPF-22. The proposed amendment would modify the TS 3.6.1.3, Primary Containment Isolation Valves (PCIVs).

The proposed change involves the Main Steam Isolation Valve (MSIV) leakage rate requirements and modifies TS Surveillance Requirement (SR) 3.6.1.3.12 to revise the leakage pathway of the main steam line (MSL) isolation system. Currently, MSL isolation system leakage is determined by verifying the allowable leakage rate through each individual MSIV and the total leakage rate through all four MSLs, including the MSL drains. Leakage is determined by Local Leak Rate Testing (LLRT) for each MSIV. Leakage results are required to be 100 standard cubic feet per hour (scfh) for individual MSIVs and 300 scfh for the combined leakage, including the MSL drains. The proposed change would revise the TS SR leakage pathway to verify the allowable leakage rate through each MSL and the total leakage rate through all four MSLs, including the MSL drains. Leakage results would be required to be 100 scfh for each MSL and 300 scfh for the combined MSLs including leakage from the MSL drains, when calculated in accordance with 10 CFR Part 50, Appendix J, Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors, methodology. As an alternative to 10 CFR Part 50 Appendix J requirements, the MSIVs are tested at a pressure of one half of Pa in between the MSIVs. The total observed leakage through both valves (inboard and outboard) is then conservatively assigned to the penetration.

April 08, 2025 Attn: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 SUSQUEHANNA STEAM ELECTRIC STATION PROPOSED AMENDMENT TO LICENSES NPF-14 AND NPF-22: MODIFICATION TO TECHNICAL SPECIFICATION 3.6.1.3 MAIN STEAM LINE ISOLATION SYSTEM LEAKAGE RATE SURVEILLANCE REQUIREMENTS PLA-8164 TALEN~

ENERGY Document Control Desk PLA-8164 provides a description and assessment of the proposed changes along with Susquehanna's determination that the proposed changes do not involve a significant hazard consideration. Attachment 2 provides the existing TS pages marked to show the proposed changes. Attachment 3 provides revised (clean) TS pages. Attachment 4 provides the existing TS Bases pages marked up to show the proposed changes and is provided for information only.

Susquehanna requests NRC approval of the proposed changes and issuance of the requested license amendment by February 28, 2026. Once approved, the amendment shall be implemented within 90 days.

In accordance with 10 CFR 50.91, Susquehanna is providing a copy of this application, with attachments, to the designated Commonwealth of Pennsylvania state official.

Both the Plant Operations Review Committee and the Nuclear Safety Review Board have reviewed the proposed changes.

There are no new or revised regulatory commitments contained in this submittal.

Should you have any questions regarding this submittal, please contact Ms. Melisa Krick, Manager - Nuclear Regulatory Affairs, at (570) 542-1818.

I declare under penalty of perjury that the foregoing is true and correct.

Executed on April 08, 2025.

E. Casulli

Attachment:

1. Description and Assessment

2. Marked-Up Technical Specification Pages

3. Revised (Clean) Technical Specification Pages

4. Marked-Up Technical Specification Bases Pages (Provided for Information Only)

Copy: NRC Region I Ms. J. England, NRC Senior Resident Inspector Ms. A. Klett, NRC Project Manager Mr. M. Shields, PA DEP/BRP

to PLA-8164 Description and Assessment

1.

SUMMARY

DESCRIPTION 2.

DETAILED DESCRIPTION 2.1 System Design and Operation 2.2 Current Technical Specifications Requirements 2.3 Reason for the Proposed Change 2.4 Description of the Proposed Change 3.

TECHNICAL EVALUATION 4.

REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedent 4.3 No Significant Hazards Considerations Analysis 4.4 Conclusions 5.

ENVIRONMENTAL CONSIDERATION 6.

REFERENCES to PLA-8164 Page 1 of 12 SUSQUEHANNA ASSESSMENT

1.

Summary Description Pursuant to 10 CFR 50.90, Susquehanna Nuclear, LLC (Susquehanna), is submitting a request for an amendment to the Technical Specifications (TS) for the Susquehanna Steam Electric Station (SSES), Units 1 and 2, Facility Operating License numbers NPF-14 and NPF-22. The proposed amendment would modify the TS 3.6.1.3, Primary Containment Isolation Valves (PCIVs).

The proposed change involves the Main Steam Isolation Valve (MSIV) leakage rate requirements and modifies TS Surveillance Requirement (SR) 3.6.1.3.12 to revise the leakage pathway of the main steam line (MSL) isolation system. Currently, MSL isolation system leakage is determined by verifying the allowable leakage rate through each individual MSIV and the total leakage rate through all four MSLs, including the MSL drains. Leakage is determined by Local Leak Rate Testing (LLRT) for each MSIV. Leakage results are required to be 100 standard cubic feet per hour (scfh) for individual MSIVs and 300 scfh for the combined leakage, including the MSL drains. The proposed change would revise the TS SR leakage pathway to verify the allowable leakage rate through each MSL and the total leakage rate through all four MSLs, including the MSL drains. Leakage results would be required to be 100 scfh for each MSL and 300 scfh for the combined MSLs including leakage from the MSL drains, when calculated in accordance with 10 CFR Part 50, Appendix J, Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors, methodology. As an alternative to 10 CFR Part 50 Appendix J requirements, the MSIVs are tested at a pressure of one half of Pa in between the MSIVs. The total observed leakage through both valves (inboard and outboard) is then conservatively assigned to the penetration (Reference 1).

2.

Detailed Description 2.1 System Design and Operation The primary objective of the containment isolation system is to provide protection by limiting release of radioactive materials outside of the containment structure. Each unit at SSES has four (4) MSLs consisting of 26-inch carbon steel pipe connecting the Reactor Pressure Vessel (RPV) to the inboard MSIV, through primary containment, to the outboard MSIV and continuing on to the main turbine and condenser system. Figure 2-1 provides a simplified diagram of the MSL to PLA-8164 Page 2 of 12 isolation system, which depicts the MSLs and associated MSIVs. For additional detail see drawings M-141, Sheet 1, which is also representative of Unit 2, in Reference 2.

Reactor Pi-essm*e Vessel Primary Containment Inboard MSIV Outboard MSIV

////Denotes Test Volume Figure 2-1: MSL Isolation System Simplified Diagram MSLto Turbine Test Connection Each MSL is equipped with two 26-inch Y-pattem, globe isolation valves; one valve is located inside of the drywell (inboard MSIV) and the other is just outside the primary containment

( outboard MSIV) in the reactor building. The MSIV s are spring-loaded, pneumatic, piston-operated globe valves designed to fail closed on loss of pneumatic pressure to the valve operator. Each valve has two independent pilot valves supplied from independent power sources. Each MSIV has an accumulator to assist in its closure upon loss of normal supply. The springs and accumulator provide a local stored energy source dedicated to closure of an MSIV under all conditions which require MSIV closure.

The MSIV s are PCIV designed to close in 2: 3 seconds to prevent a reactor vessel over pressure transients and :::; 5 seconds to contain fission products and ensure the core is not uncovered following a line break. The MSIV s isolate on the following signals: Reactor Vessel Water Level

- Low Low Low, Level 1, Main Steam Line Pressure - Low, Main Steam Line Flow - High, Condenser Vacuum - Low, and Reactor Building Main Steam Tunnel Temperature - High. TS 3.3.6.1, Primary Containment Isolation Instrumentation, performs SRs on the associated to PLA-8164 Page 3 of 12 channels providing reasonable assurance the MSIVs can perform their safety function throughout the cycle. These include Channel Checks, Channel Functional Tests, and Channel Calibrations. A single failure in the MSIV isolation logic will not prevent MSIV closure (Reference 3). The SR frequencies are determined by the Surveillance Frequency Control Program.

The Primary Containment Leakage Rate Testing Program implements the requirements of 10 CFR 50 Appendix J and governs the testing requirements of all MSIVs. As an alternative to 10 CFR Part 50 Appendix J requirements, the MSIVs are tested at a pressure of one half of Pa in between the MSIVs. The total observed leakage through both valves (inboard and outboard) is then conservatively assigned to the penetration. LLRT on the MSIVs are performed every refueling outage. MSIV LLRTs currently use an acceptance criterion for operability of 100 scfh through each MSIV and 300 scfh for the combined leakage, including the MSL drains, when the MSIVs are tested at 24.3 psig or Pa and the MSL drains are tested at Pa, where Pa is the calculated peak containment internal pressure related to the Design Basis Accident (DBA). At Susquehanna, Pa = 48.6 psig. The result is that both the inboard and outboard MSIV, individually, are required to satisfy the 100 scfh requirement. When a single MSIV in a line exceeds the 100 scfh requirement, a condition report is generated, and remediation is controlled by the corrective action program. The MSL drains are subject to Type C testing in accordance with the Primary Containment Leakage Rate Testing Program and the results are added to the MSLs to determine the combined total leakage. The proposed change will not impact the test method associated with the MSL drains or how the cumulative MSL leakage is calculated.

2.2 Current Technical Specifications Requirements Limiting Condition of Operation (LCO) 3.6.1.3 requires, for each unit, that each PCIV be operable in Modes 1, 2, and 3. TS SR 3.6.1.3.12 verifies the leakage rate through each MSIV is 100 scfh and 300 scfh for the combined leakage including the leakage from the MSL drains when the MSIVs are tested at 24.3 psig or Pa and the MSL drains are tested at Pa (i.e., 48.6 psig).

2.3 Reason for the Proposed Change The reason for the proposed change is to align the leakage pathway description in TS SR 3.6.1.3.12 with the assumptions in the control room habitability envelope and off-site post loss of coolant accident dose analysis. As discussed in Section 15.6 of the Susquehanna Updated Final Safety Analysis Report (FSAR), the analysis for MSIV leakage path assumes one MSL is faulted and the faulted line has 100 scfh flow. The remaining leakage is evenly split between the to PLA-8164 Page 4 of 12 three non-faulted lines. Revising the TS SR leakage pathway from each MSIV to each MSL aligns with the analysis.

2.4 Description of the Proposed Change The proposed change revises TS SR 3.6.1.3.12 to verify leakage through each MSL is 100 scfh and 300 scfh for the combined leakage including the leakage from the MSL drains, when tested at 24.3 psig or Pa and the MSL drains are tested at Pa. The proposed TS changes are provided in Attachment 2 and 3. Conforming changes are made to the TS Bases, and are provided in Attachment 4 for information only.

3.

Technical Evaluation The primary objective of the containment isolation system is to provide protection by limiting release of radioactive materials outside of the containment structure. The MSLs have independent redundant MSIVs intended to isolate main steam and radioactive fission products inside containment. To meet 10 CFR 50 Appendix A, General Design Criterion (GDC) 16, all four MSLs are required to isolate and satisfy the safety function requirement. The proposed change to the operability of a single MSIV in a line, to the MSL is consistent with GDC 16 requirements in that the safety function requirement remains satisfied. The Primary Containment Leakage Rate Testing Program identified the MSIVs are Type C tested at least once every 30 months. As an exception to the Primary Containment Leakage Rate Testing Program, MSIV leakage rates are not included in combined Type B and Type C as-found and as-left pathway leakage rates (i.e., 0.60 La, where La is the maximum allowable leakage rate from primary containment at a pressure of Pa expressed in percent per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />). The Inservice Testing (IST)

Program Plan identifies the MSIVs are exempt from the quarterly testing requirements of OM Code ISTC-3500, 1998 Edition through 2006 Addenda, as the evolution during normal power operations presents risks of a reactor trip or safety system actuation. The proposed change has no impact on the IST program.

Section 6.2.6.3 of the FSAR identifies MSIV leakage is assigned according to ANSI/ANS 56.8-1994, Containment System Leakage Testing Requirements (Reference 4). Regulatory Guide 1.163, Revision 0, Performance-Based Containment Leak-Test Program (Reference 5), provides guidance on an acceptable performance-based leak-test program and leakage rate test methods, procedures, and analyses that may be used to comply with Option B - Performance-Based Requirements in Appendix J to 10 CFR Part 50. RG 1.163 endorses ANSI/ANS 56.8-1994 which provides the methodology to determine penetration leakage. It is noted that in Reference 6, Susquehanna submitted a proposed license amendment to adopt RG 1.163, Revision 1 (Reference 7), and ANSI/ANS 56.8-2020 (Reference 8). Susquehanna has confirmed that the proposed adoption of RG 1.163, Revision 1, and ANSI/ANS 56.8-2020 has no impact to the proposed changes herein (i.e., the requirements of RG 1.163, Revision 0, and ANSI/ANS 56.8-1994 are consistent with those in RG 1.163, Revision 1, and ANSI/ANS 56.8-2020). RG 1.163, to PLA-8164 Page 5 of 12 Revision 1, will be implemented after approval of the proposed license amendment in Reference 6.

ANSI/ANS 56.8-1994 defines two methods, minimum pathway leakage rate (MNPLR) and maximum pathway leakage rate (MXPLR), to calculate the leakage rate for a penetration.

MNPLR is defined as the minimum leakage rate that can be attributed to a penetration leakage path (i.e., the smaller of either the inboard or outboard barrier's individual leakage rates). The pathway's MNPLR can be determined by one-half of the total measured leakage rate when tested by pressurizing between the inboard and outboard barriers. MXPLR is defined as the maximum leakage rate attributed to a penetration leakage path. The MXPLR is the larger, not the total, leakage of two barriers in series.

The MSIV leakage rate is evaluated on a MNPLR basis when containment past operability is required (as-found leakage), consistent with the requirements of the Primary Containment Leakage Rate Testing Program. The proposed change revises the TS SR leakage pathway to the MSL instead of the individual MSIVs. The MSL leakage rate will be evaluated on a MNPLR basis for as-found leakage similar to the individual MSIVs. The MNPLR is compared to the design basis to assess operability and reportability for the MSL. Testing of the MSLs will continue to perform LLRT on both the inboard and outboard MSIVs, ensuring the safety function of the MSIVs can be performed and leakage rates for each valve are understood. Prior to the unit returning to a mode where containment operability is required, the MSL, including the inboard and outboard MSIV, LLRT results will be evaluated on a MXPLR basis (as-left leakage). Evaluating on a MXPLR basis ensures the MSL, and associated MSIVs, are below the individual MSL leakage rate limit (i.e., operable) prior to the unit entering a mode where containment operability is required.

Revising the leakage rate pathway in TS SR 3.6.1.3.12 does not impact how as-found and as-left leakage testing is conducted or assigned for each MSIV and MSL. The proposed change will continue to follow ANSI/ANS 56.8 leakage rate testing methodology ensuring the safety function of the main steam isolation system is retained.

Dose Impacts The MSIV leakage limits are established to limit the radiological consequences for the following:

Control Room Operators (10 CFR 50.67)

An individual at the Exclusion Area Boundary (10 CFR 50.67)

An individual at the Low Population Zone (10 CFR 50.67)

Individuals occupying the Technical Support Center and the Security Center Environmental Qualification of equipment in areas of the plant potentially affected to PLA-8164 Page 6 of 12 by MSIV leakage (10 CFR 50.49)

Revising the leakage verification pathway from individual MSIVs to leakage through individual MSLs will not impact the control room habitability envelope and off-site dose calculation.

FSAR Section 15.6 states the analysis assumes one MSL is faulted and the faulted line has 100 scfh flow. The remaining leakage is evenly split between the three non-faulted lines. This scenario bounds any case where leakage through a single MSIV is > 100 scfh if the paired MSIV, upstream or downstream, has leakage 100 scfh. The total allowable leak rate for all four MSLs will remain 300 scfh.

4.

Regulatory Evaluation 4.1 Applicable Regulatory Requirements/Criteria General Design Criteria During the applicable period of this proposed license amendment, SSES will maintain the ability to meet the applicable GDC as described in FSAR Section 3.1.

GDC-16, Containment Design Reactor containment and associated systems shall be provided to establish an essentially leak-tight barrier against the uncontrolled release of radioactivity to the environment and to assure that the containment design conditions important to safety are not exceeded for as long as postulated accident conditions require.

GDC-56, Primary Containment Isolation Each line that connects directly to the containment atmosphere and penetrates primary reactor containment shall be provided with containment isolation valves as follows, unless it can be demonstrated that the containment isolation provisions for a specific class of lines, such as instrument lines, are acceptable on some other defined basis:

1) One locked closed isolation valve inside and one locked closed isolation valve outside containment; or

2) One automatic isolation valve inside and one locked closed isolation valve outside containment; or

3) One locked closed isolation valve inside and one automatic isolation valve outside containment. A simple check valve may not be used as the automatic isolation valve outside containment; or to PLA-8164 Page 7 of 12

4) One automatic isolation valve inside and one automatic isolation valve outside containment. A simple check valve may not be used as the automatic isolation valve outside containment.

Isolation valves outside containment shall be located as close to the containment as practical and upon loss of actuating power, automatic isolation valves shall be designed to take the position that provides greater safety.

Conclusion The proposed change to TS SR 3.6.1.3.12 will not impact any installed components at SSES.

The PCIV functions of the MSIVs are not impacted by the proposed change which revises only the leakage rate verification. The PCIVs will continue to be able to perform their intended function to mitigate the consequences of an event.

4.2 Precedent In Reference 9, the NRC granted approval to Peach Bottom Atomic Power Station (PBAPS),

Units 2 and 3, for an amendment to revise TS 3.6.1.3, Primary Containment Isolation Valves (PCIVs). The amendment revised TS SR 3.6.1.3.14 to increase the allowable combined leakage for all MSIV leakage paths. The change also revised the leakage pathway from MSIVs to MSLs.

Unlike PBAPS, the proposed amendment herein is only requesting to revise the leakage pathway identified in TS SR 3.6.1.3.12.

In Reference 10, supplemented by Reference 11, Constellation Energy Generation, LLC, proposed a change to the Limerick Generating Station (Limerick) Units 1 and 2 TS 3.6.1.2, Primary Containment Leakage. The proposed changes revises the leakage pathway from any one MSIV to any one MSL. During the application process, Limerick stated the change aligns with the ANSI/ANS 56.8 methodology and continues to ensure the MSIVs remain within their intended design. This request is in NRC review. The request for supplemental information needed for acceptance associated with Limericks proposed change has been reviewed and addressed in Susquehannas proposed amendment.

PBAPS and Limerick are Boiling Water Reactor 4 design, consistent with SSES, Units 1 and 2.

Therefore, the identified precedent is relevant to SSES, Units 1 and 2.

4.3 No Significant Hazards Considerations Analysis In accordance with the requirements of 10 CFR 50.90, Susquehanna Nuclear, LLC (Susquehanna), requests an amendment to the Technical Specifications (TS) for the Susquehanna Steam Electric Station (SSES), Units 1 and 2. The proposed change involves the Main Steam Isolation Valve (MSIV) leakage rate requirements. The proposed change modifies to PLA-8164 Page 8 of 12 TS Surveillance Requirement (SR) 3.6.1.3.12 to revise the leakage pathway of the main steam line (MSL) isolation system. Currently, MSL isolation system leakage is determined by verifying the allowable leakage rate through each individual MSIV and the total leakage rate through all four MSLs, including the MSL drains. Leakage is determined by Local Leak Rate Testing (LLRT) for each MSIV. Leakage results are required to be 100 standard cubic feet per hour (scfh) for individual MSIVs and 300 scfh for the combined leakage, including the MSL drains. The proposed change would revise the TS SR leakage pathway to verify the allowable leakage rate through each MSL and the total leakage rate through all four MSLs, including the MSL drains. Leakage results would be required to be 100 scfh for each MSL and 300 scfh for the combined MSLs including leakage from the MSL drains, when calculated in accordance with 10 CFR Part 50, Appendix J, Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors, methodology.

Susquehanna has evaluated the proposed amendment against the standards in 10 CFR 50.92 and has determined that the operation of SSES in accordance with the proposed amendment presents no significant hazards. Susquehannas evaluation against each of the criteria in 10 CFR 50.92 follows.

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

Response: No The proposed change revises TS SR 3.6.1.3.12 to remove the requirement of verifying leakage rates through each MSIV and combined leakage through all MSL, including MSL drains, to verifying leakage through each MSL and combined leakage through all MSLs, including MSL drains. Previously evaluated accident analyses bound any leakage through a single MSIV with

>100 scfh when a paired MSIV, upstream or downstream, has leakage 100 scfh. The combined MSL leakage rate requirement of 300 scfh ensures the MSLs, including drains, remain within their design to limit the effect of radioisotopes exiting the primary containment.

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 There are no new or different accident results from implementing the proposed changes. The changes do not alter the design or function of primary containment isolation and main steam line isolation systems. When a single MSIV in a line exceeds the action criteria for LLRT to PLA-8164 Page 9 of 12 leakage results, a condition report is generated, and remediation is controlled by the corrective action program. Previously evaluated accident analyses bound any leakage through a single MSIV with >100 scfh when a paired MSIV, upstream or downstream, has leakage 100 scfh. The combined MSL leakage rate requirement of 300 scfh ensures the MSLs, including drains, remain within their design to limit the effect of radioisotopes exiting the primary containment.

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 changes will not cause a significant reduction in the margin of safety considering operability will be determined by the single main steam line in which there are two independent and redundant MSIVs, where only one is needed to maintain the safety function associated with main steam isolation. The combined leakage rate limit ensures the MSIVs remain within their design to limit the effect of radioisotopes exiting the primary containment.

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

Based on the above evaluation, Susquehanna concludes that the proposed amendment does not involve a 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.

4.4 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 Commissions 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.

5.

Environmental Consideration Susquehanna has determined that the proposed amendment 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 amendment does not involve (i) a significant hazards consideration, (ii) a significant to PLA-8164 Page 10 of 12 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 amendment 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 amendment.

to PLA-8164 Page 11 of 12

6.

References

1.

NUREG-0776, Safety Evaluation Report Related to the Operation of Susquehanna Steam Electric Station, Units 1 and 2, dated April 1981 (ADAMS Accession No. ML17139A104).

2.

Susquehanna Steam Electric Station - Submittal of Revision 71 to Updated Final Safety Analysis Report and Revision 25 to Fire Protection Review Report, dated October 12, 2023 (ADAMS Accession No. ML23291A105).

3.

Susquehanna, Units 1 and 2, Technical Specifications Bases Manual, dated January 06, 2023 (ADAMS Accession No. ML23017A055 and ML23017A046).

4.

American Nuclear Society, ANSI/ANS 56.8-1994, Containment System Leakage Testing Requirements, La Grange Park, Illinois, dated August 1994 (ADAMS Accession No. ML11327A024).

5.

NRC Regulatory Guide 1.163, Performance-Based Containment Leak-Test Program, Revision 0, dated September 1995 (ADAMS Accession No. ML003740058).

6.

Susquehanna letter to NRC, Request to Revise Technical Specification 5.5.12, Primary Containment Leakage Rate Testing Program, for Permanent Extension of Type A and Type C Leak Rate Testing Frequencies and Permanently Extend the Drywell Bypass Leakage Test Frequency, dated November 01, 2024 (ADAMS Accession No. ML24306A122).

7.

NRC Regulatory Guide 1.163, Performance-Based Containment Leak-Test Program, Revision 1, dated June 2023 (ADAMS Accession No. ML23073A154).

8.

American Nuclear Society, ANSI/ANS 56.8-2020, Containment System Leakage Testing Requirements, La Grange Park, Illinois, dated December 2020.

9.

NRC letter to Exelon Generation Company, LLC, Peach Bottom Atomic Power Station, Units 2 and 3 - Issuance of Amendments Re: Application of Alternative Source Term Methodology (TAC Nos. MD6806 and MD6807), dated September 05, 2008 (ADAMS Accession No. ML082320257).

10.

Constellation Energy Generation, LLC letter to NRC, License Amendment Request for Modification to Technical Specification 3.6.1.2 and Main Steam Isolation Valve Leakage Rate Requirements, dated August 28, 2024 (ADAMS Accession No. ML24241A195).

to PLA-8164 Page 12 of 12

11.

Constellation Energy Generation, LLC letter to NRC, Response to Request for Supplemental Information Needed for Acceptance of Requested Licensing Action Regarding Primary Containment Leakage Technical Specifications, dated October 25, 2024 (ADAMS Accession No. ML24299A264).

of PLA-8164 Marked-Up Technical Specification Pages Revised Technical Specifications Pages Unit 1 TS Pages 3.6-15 Unit 2 TS Pages 3.6-15

PCIVs 3.6.1.3 SUSQUEHANNA - UNIT 1 3.6-15 Amendment 178, 190, 246, 251, 266, 271, XXX SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.1.3.10 Remove and test the explosive squib from each shear isolation valve of the TIP System.

In accordance with the Surveillance Frequency Control Program SR 3.6.1.3.11 Verify the combined leakage rate for all secondary containment bypass leakage paths is 15 scfh when pressurized to Pa.