ML25311A090
| ML25311A090 | |
| Person / Time | |
|---|---|
| Site: | FitzPatrick  |
| Issue date: | 11/07/2025 |
| From: | Knowles J Constellation Energy Generation |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| JAFP-25-0055, EPID L-2025-LLA-0088 | |
| Download: ML25311A090 (1) | |
Text
200 Energy Way Kennett Square, PA 19348 www.constellation.com 10CFR 50.90 JAFP-25-0055 November 7, 2025 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 James A. FitzPatrick Nuclear Power Plant Renewed Facility Operating License No. DPR-59 NRC Docket No. 50-333
Subject:
Response to NRC Request for Additional Information Regarding License Amendment Request for Proposed Changes to the Technical Specification Primary Containment Isolation Instrumentation Tables and New Main Steam Tunnel Area Temperature Technical Specification 3.7.8 (EPID L-2025-LLA-0088)
References
- 1. Letter from J. Knowles (Constellation Energy Generation, LLC (CEG)) to the U.S. Nuclear Regulatory Commission, License Amendment Request for Proposed Changes to the Technical Specification Primary Containment Isolation Instrumentation Tables and New Main Steam Tunnel Area Temperature Technical Specification 3.7.8, JAFP-24-0034, dated May 29, 2025 (ADAMS Accession No ML25149A172)
- 2. Electronic mail from R. Guzman (U.S. Nuclear Regulatory Commission) to M. Henry (Constellation Energy Generation, LLC (CEG)), James A.
FitzPatrick - Request for Additional Information Re: LAR for Proposed Changes to the TSs - Primary Containment Isolation Instrumentation Tables and New Main Steam Tunnel Area Temperature Technical Specification 3.7.8 (EPID L-2025-LLA-0088), dated September 23, 2025 (ADAMS Accession No. ML25267A007)
By \
letter dated May 29, 2025 (Reference 1), Constellation Energy Generation, LLC (CEG) requested change the James A. FitzPatrick Nuclear Power Plant (JAF) Technical Specifications (TS) 3.3.6.1 to remove Trip Function 1.e, "Main Steam Tunnel Area Temperature - High," and to insert the word "Deleted" in Table 3.3.6.1-1 Trip Function 1.e. In addition, the proposed change adds a new TS Limiting Condition for Operation (LCO) 3.7.8, "Main Steam Tunnel (MST) Area Temperature." The new LCO 3.7.8 requires the MST area maximum temperatures be maintained less than or equal to 195°F.On September 4, 2025, the NRC Senior Project Manager for JAF emailed to CEG a draft Request for Additional Information (RAI) question in support of the NRCs review. On September 10, 2025, a clarification call was conducted with the NRC to ensure understanding of the draft RAI question. On September 23, 2025, the NRC Senior Project Manager issued the final RAI question to CEG (Reference 2).
Response to RAI Regarding License Amendment Request for Main Steam Tunnel Area Temperature November 7, 2025 Page 2 The Attachment to this letter contains the NRCs RAI question immediately followed by CEGs response.
The additional information provided in this submittal does not affect the conclusion that the proposed license amendment does not involve a significant hazards consideration. This additional information also does not affect the conclusion that neither an environmental impact statement nor an environmental assessment need be prepared in support of the proposed amendment.
This letter and its attachment contain no new regulatory commitments.
Should you have any questions concerning this supplement, please contact Michael Henry at (267) 533-5382.
Respectfully, Justin W. Knowles Sr. Manager - Licensing Constellation Energy Generation, LLC
Attachment:
Request for Additional Information and CEG Response cc:
USNRC Region I, Regional Administrator USNRC Senior Resident Inspector, James A. FitzPatrick Nuclear Power Plant USNRC Project Manager, NRR - James A. FitzPatrick Nuclear Power Plant Knowles, Justin W
Digitally signed by Knowles, Justin W Date: 2025.11.07 07:03:57 -05'00'
ATTACHMENT Request for Additional Information and CEG Response James A. FitzPatrick Nuclear Power Plant Renewed Facility Operating License No. DPR-59 NRC Docket No. 50-333
Attachment Request for Additional Information and CEG Response Page 1 of 3 Introduction By \
letter dated May 29, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25149A172), Constellation Energy Generation, LLC (CEG) submitted a License Amendment Request (LAR) for James A. FitzPatrick Nuclear Power Plant (JAF). The proposed amendment would revise the technical specifications (TS) to eliminate the requirement for automatic Main Steam Line (MSL) isolation based on the temperature in the Main Steam Tunnel (MST) Area. In lieu of automatic isolation, a new specification is proposed that would require manual action when the MST Area temperature is above the limit.
Specifically, the proposed amendment would revise TS Limiting Condition for Operation (LCO) 3.3.6.1, Table 3.3.6.1-1, by deleting Trip Function 1.e, "Main Steam Tunnel Area Temperature -
High," and inserting the word "Deleted" in Table 3.3.6.1-1, "Primary Containment Isolation Instrumentation," for the deleted Trip Function 1.e. The proposed change adds a new TS LCO 3.7.8, "Main Steam Tunnel (MST) Area Temperature," to require MST Area maximum temperatures to be maintained less than or equal to 195°F. The proposed change also adds a new corresponding surveillance requirement to verify that the MST Area temperatures are maintained less than or equal to 195°F on a frequency controlled by the Surveillance Frequency Control Program.
The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the information provided in the submittal and has determined that additional information as requested in the below is needed to complete its review.
Regulatory Basis The regulation in Title 10 of the Code of Federal Regulations (10 CFR) Section 50.49 requires that electrical equipment important to safety be capable of performing their safety functions under all postulated environmental conditions, including temperature, for the entire qualified life of the equipment. The qualification process must demonstrate, prior to installation and continually during operation, that systems, structures, and components (SSCs) important to safety will function as required under the most limiting environmental conditions of normal operation, anticipated operational occurrences, and accident scenarios. If plant environmental conditions changesuch as those resulting from a revised operating temperature profile licensees must reassess and, if necessary, update their qualification documentation and analyses to ensure continued compliance with 10CFR 50.49. This includes considering cumulative exposure and the effects of aging, not only initial type-testing.
When SSCs important to safety operate in environments and/or for durations not fully covered by their qualification basis, there is an increased risk of unexpected failure mechanisms emergingespecially during accident conditions, where multiple severe stresses (temperature, pressure, radiation, etc.) may act simultaneously. Extended or even intermittent operation above a temperature setpoint threshold without automatic isolation may inadvertently expose SSCs important to safety to conditions exceeding their original qualification, leading to undetected age-related or installation-induced degradation manifesting as failures under stress. Operating above a temperature threshold may also affect determination of environmental qualification zones (i.e., result in adding or expanding an environmental qualification zone due to changes in initial condition assumptions).
Attachment Request for Additional Information and CEG Response Page 2 of 3 Request for Additional Information The NRC staff notes that depending on the timing to complete the post-threshold engineering reviews of qualified Structures, Systems, and Components (SSCs), there is potential for prolonged exposure to elevated temperatures that can significantly degrade materials and components, potentially affecting mechanical strength, electrical insulation, and sealing performance, thereby shortening the qualified life and potentially impacting the functional capability of SSCs requiring qualification.
As stated in the LAR, Removing the automatic isolation function and adding a reactor shutdown requirement on high MST area temperature will have no adverse effect on equipment qualification.
Once the 195ºF temperature threshold is entered, procedural guidance will trigger an engineering review of qualified SSCs to evaluate the actual condition and any remedial actions.
The staff requests the licensee to provide justification as to how the stated determination was reached and explain how environmental qualification zones have been or would be assessed when/if temperatures exceed the 195ºF threshold. Additionally, with respect to the inclusion of procedural guidance requiring post-threshold engineering review of qualified SSCs (i.e., manual actions), provide the supporting rationale for the timely identification and remediation of qualification issues to ensure the continued qualification of equipment, including possible adverse impacts on material integrity, functional performance, and qualified life due to sustained high temperatures.
CEG Response to RAI:
The JAF Environmental Qualification (EQ) Program, in accordance with 10 CFR 50.49, Environmental qualification of electric equipment important to safety for nuclear power plants, defines the interfaces between the EQ Engineer and other site departments to ensure required EQ equipment is properly installed and maintained. CEG implements an EQ program with procedure CC-AA-203 Environmental Qualification Program, Revision 18. The EQ report JAF-RPT-MISC-04046 Environmental Qualification Service Conditions, Revision 1 identifies specific plant areas as EQ Environmental Zones and details their subsequent environmental parameters. These parameter sets consist of normal and accident conditions including temperature, radiation, humidity, water and chemical spray, pressure, and submergence are based upon design calculations that are updated with historical data and operating experience.
EQ concerns are managed through the JAF EQ procedures in conjunction with the Corrective Action Program (CAP). JAF procedure ST-40D Daily Surveillance and Channel Check Revision 128, specifically monitors steam tunnel temperatures during the performance of channel checks and will continue to monitor MST area temperature with the newly created SR 3.7.8.1. A procedural note mandates the creation of an Issue Report and an EQ evaluation if normal temperature thresholds are exceeded. Temperature excursions reaching the newly proposed LCO limit will activate control room annunciators for elevated temperature and prompt a condition assessment. Should temperatures in the MST Area meet the criteria for entry into the proposed MST Area Temperature LCO, site procedures and CEG Procedure PI-AA-120,
Attachment Request for Additional Information and CEG Response Page 3 of 3 "Issue Identification and Screening Process" (Revision 14), will initiate an evaluation that considers equipment performance and potential impacts.
Automatic MSL Isolation is not assumed as a mitigating design feature in the EQ program and elimination of this automatic isolation does not have an adverse impact on the EQ program. The JAF MST area normal operating temperatures are not changed because of this License Amendment Request so there will be no new EQ zones created and no changes to the existing EQ zones. All affected EQ zones are currently managed within the scope of the existing program. For higher-than-expected temperature readings in the MST area, the procedural guidance will direct an engineering assessment of the qualified life of the EQ equipment located within the respective EQ Environmental zone.