ML26029A398
| ML26029A398 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 01/28/2026 |
| From: | Hart T Ameren Missouri, Union Electric Co |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| Shared Package | |
| ML26029A397 | List: |
| References | |
| ULNRC-06922 | |
| Download: ML26029A398 (0) | |
Text
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 NI, Callaway Plant Ameren MISSOURI January 28, 2026 ULNRC-06922 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 10 CFR 50.12 10 CFR 50.67 10 CFR 50.90 10 CFR 2.390 Ladies and Gentlemen:
DOCKET NUMBER 50-483 CALLAWAY PLANT UNIT 1 UNION ELECTRIC CO.
RENEWED FACILITY OPERATING LICENSE NPF-30 LICENSE AMENDMENT REQUEST FOR TRANSITION TO UPGRADED WESTINGHOUSE FUEL, ADOPTION OF NEW ANALYTICAL METHODS, AND INCREASE IN ALLOWABLE FUEL BURNUP (LDCN 24-0014)
References:
Provided on page 7.
Pursuant to 10 CFR 50.90, Application for amendment of license or construction permit, Ameren Missouri (Union Electric Company) herewith transmits an application for amendment to Facility Operating License Number NPF-30 for the Callaway Plant, Unit 1 (Callaway). The proposed license amendment has the following major themes: transition to an upgraded fuel assembly design with improved materials, adoption of improved analysis methods, an incremental increase in allowable fuel burnup, and adoption of Technical Specification (TS) Travelers TSTF-51, TSTF-471 and TSTF-571.
These changes result in a more robust, accident tolerant fuel product, supported by safety analysis aligned with current regulatory guidance, and offer increased operational flexibility.
Enclosures 2 and4 to this letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 8315 County Road 459 Steedman, MO 65077 AmerenMissouri.com
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 ULNRC-06922 January 28, 2026 Page 2 of 10 The fuel assembly-related changes include transition from VANTAGE+ fuel to VANTAGE+ fuel with an enhanced PRIME'fuel assembly skeleton, use of ADOPT'fuel pellets, and transition to AXIOM cladding. These changes enhance fuel design by improving debris protection, thermal performance, cladding corrosion resistance, and high-burnup performance.
The improved analysis methods include implementation of the FSLOCA'evaluation model, PADS for improved fuel rod performance modeling, and an updated control rod ejection accident analysis.
These changes update Callaway's supporting analyses to the current regulatory guidance and address issues with the older evaluation models. These updated analyses include an updated mass and energy release calculation for containment resulting in a slight increase in the peak post-loss of coolant accident containment pressure.
The change also includes adoption of analyses and evaluations necessary to operate core peripheral fuel assemblies at a rod-average burnup above the current Callaway burnup limit of 62 GWd/MTU.
Associated with the increased burnup limit allowance, Callaway will transition to alternative source terms (ASTs) for radiological dose analyses consistent with Regulatory Guide 1.183, Revision l for fuel related events.
As a result of the positive results of the updated safety analyses and updated AST analyses, Callaway proposes to adopt TSTF.51-A, TSTF-471-A and TSTF-571-T (References 11, 12 and 13, respectively) which eliminate the term CORE ALTERATIONS, modify Applicability statements, Notes and Actions to differentiate requirements for handling of recently irradiated fuel from those requirements for handling fuel with substantial post-irradiation decay time, and modifies an Action for an inoperable source range monitor.
In support of the fuel transition and updated analysis methods, the following Technical Specifications (TSs) will require revision: TS 2.1.1, "Reactor Core SLs," to reflect the use of ADOPT'fuel; TS 4.2.1, "Fuel Assemblies, to reflect the use of AXIOM cladding and use of integral dopants, TS 5.5.16, "Containment Leakage Rate Testing Program, to reflect a new peak calculated containment internal pressure, Pa, and TS 5.6.5, "Core Operating Limits Report (COLR)," to reflect updated analytical methods.
In support of the adoption of TSTF-51-A, TSTF-471-A and TSTF-571-T, the following TSs will require revision: TS 1.1, "Definitions," TS 3.3.6, Containment Purge Isolation Instrumentation,"
TS 3.3.7, "Control Room Emergency Ventilation System (CREVS) Actuation Instrumentation, TS 3.3.8, "Emergency Exhaust System (EES) Actuation Instrumentation, TS 3.7.10, Control Room Emergency Ventilation System (CREVS), TS 3.7.11, "Control Room Air Conditioning System (CRACS)," TS 3.7.13, "Emergency Exhaust System (EES), TS 3.8.2, "AC Sources Shutdown,"
TS 3.8.5, "DC Sources Shutdown," TS 3.8.8, "Inverters Shutdown," TS 3.8.10, "Distribution Enclosures 2 and 4 tothis letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CER 2.390 ULNRC-06922 January 28, 2026 Page 3 of 10 Systems Shutdown, TS 3.9.1, "Boron Concentration," TS 3.9.2, "Unborated Water Source Isolation Valves," TS 3.9.3, "Nuclear Instrumentation," and TS 3.9.4, "Containment Penetrations."
Pursuant to 10 CFR 50.12, Ameren Missouri additionally requests an exemption from the requirements of 10 CFR 50.46 to support the Callaway application of AXIOM cladding.
It may be noted that this request for license amendment was discussed with the NRC staff in a public pre-submittal meeting (telephone conference) conducted on March 4, 2025 (Reference 1), as summarized in Reference 2. Subsequent to the meeting, two significant changes occurred. The first involved the deferral of the license amendment submittal until the fall of 2025 and the second involved the addition of TSTF-51-A, TSTF-471-A and TSTF-571-T to the amendment request scope. The deferral was necessitated as a risk mitigation measure given the overlap between fuel procurement, fabrication and delivery, and the amendment approval time frame. The second change was the result of obtaining AST calculation results that were not available at the time of the first meeting. These results support the implementation of the referenced TSTFs. This request for license amendment was discussed a second time with the NRC staff in a public pre-submittal meeting (telephone conference) conducted on December 16, 2025 (Reference 14).
Enclosurel to this letter provides Ameren Missourts evaluation of the proposed change.
Attachments l through 4 to Enclosure 1 provide the markup of the Technical Specifications, the retyped Technical Specifications, a markup of the proposed Technical Specification Bases, and a markup of the proposed Final Safety Analysis Report (FSAR) description related to the control rod ejection event methodology, respectively, in support of this amendment request. The TS Bases markups (i.e., Attachment 3) are provided for information only. Final TS Bases changes will be processed under the program for updates per TS 5.5.14, Technical Specifications Bases Control Program, at the time this amendment is implemented. Attachment4 is provided for information only.
Final FSAR changes will be incorporated into the Callaway licensing basis in accordance with 10 CFR 50.7 1(e) at the time this amendment is implemented. provides the justification for compliance with the limitations and conditions from the Safety Evaluation Reports (SERs) which have been integrated into the following approved and verified Topical Reports: WCAP-16996-P-A, WCAP-18482-P-A, WCAP-18546-P-A, WCAP-18446-P-A, and WCAP-17642-P-A as provided in References 3, 4, 5,6 and 7. Enclosure 3 provides the nonproprietary version of the information. provides a plant specific justification for the application of WCAP-15806-P-A (Reference 8) to address Regulatory Guide (RG) 1.236, Pressurized-Water Reactor Control Rod Ejection and Boiling-Water Reactor Control Rod Drop Accidents. Enclosure 5 provides the nonproprietary version of the information.
Enclosures 2 and 4 to this letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 ULNRC-06922 January 28, 2026 Page 4 of 10 provides the exemption request from the applicable acceptance criteria of 10 CFR 50.46 to support Callaway application of AXIOM cladding. and Enclosure 4 contain information that Westinghouse Electric Company LLC (Westinghouse) considers to be proprietary in nature. Pursuant to 10 CFR 2.390(a)(4), Ameren Missouri requests that the proprietary information be withheld from public disclosure. Enclosure 7 provides the Westinghouse Application for Withholding Proprietary Information from Public Disclosure CAW-25-003 affidavit supporting the proprietary withholding request for Enclosure 2 and. The request is supported by an affidavit signed by Westinghouse, the owner of the information. The affidavit sets forth the basis on which the information may be withheld from public disclosure by the Nuclear Regulatory Commission (Commission) and addresses with specificity the considerations listed in paragraph (b)(4) of Section 2.390 of the Commission's regulations.
Accordingly, Ameren Missouri requests that the information which is proprietary to Westinghouse be withheld from public disclosure in accordance with 10 CFR Section 2.390 of the Commission's regulations. Correspondence with respect to the copyright or proprietary aspects of the items listed above or the supporting Westinghouse affidavit should reference CAW-25-003 and be addressed to Jerrod Ewing, Manager, Operating Plants Licensing, Westinghouse Electric Company, 1000 Westinghouse Drive, Cranberry Township, Pennsylvania 16066.
As part of this amendment request, Callaway is requesting an incremental increase in the maximum allowed fuel burnup beyond the current limit of 62 gigawatt days per metric ton of uranium (GWD/MTVU). In accordance with the guidance provided in RG 1.183, Revision 1, this action necessitates adoption of revised alternative source terms and an update to the radiological consequences for two fuel-dependent FSAR-described events. Enclosure 8 provides a plant-specific description of the adoption of RG 1.183 Revision 1 for these specific FSAR-described events.
Ameren Missouri has determined that this amendment application does not involve a significant hazard consideration as defined in 10 CFR 50.92, Issuance of amendment. Pursuant to 10 CFR 51.22, Criterion categorical exclusion or otherwise not requiring environmental review, Section (b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of this amendment. In accordance with 10 CFR 50.91 Notice for public comment; State consultation, Section (b)(1), a copy of this amendment application is being provided to the designated Missouri State official.
This submittal does not contain new commitments. This submittal does provide fulfillment of a commitment provided in Reference 10 to submit a license amendment request that documents a LOCA reanalysis using the FSLOCA methodology (Reference 3).
Enclosures 2 and 4 to this letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 ULNRC-06922 January 28, 2026 Page 5 of 10 In accordance with the Callaway Operating Quality Assurance Manual, the Onsite Review Committee has reviewed and approved the proposed changes and has approved the submittal of this amendment application.
Ameren Missouri requests approval of the requested license amendment within one year of its acceptance, and that it be made effective upon issuance. Ameren Missouri intends to implement the license amendment provisions associated with TSTF-51, TSTF-471 and TSTF-571 prior to or during refueling outage 29 which is currently planned to commence in the spring of 2028. Ameren Missouri intends to implement the balance of the fuel transition related amendment provisions prior to reloading the core in preparation for operating cycle 30.
If there are any questions, please contact Thomas Elwood, Manager, Regulatory Affairs, at 314-225-1905.
I declare under penalty of perjury that the foregoing is true and correct.
Sincerely, Travis Hart Senior Director, Nuclear Operations And Plant Manager Executed on:
Enclosures 2 and 4 to this letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 ULNRC-06922 January 28, 2026 Page 6 of 10
Enclosures:
I.
Description and Assessment of the Proposed Change, including the following: -Technical Specifications Page Markups
- Retyped Technical Specifications Pages
- Proposed Technical Specifications Bases Page Markups
- Proposed FSAR Page Markups for the Rod Ejection Event Limitations and Conditions Compliance for WCAP-18482-P-A, WCAP-18546-P-A, WCAP-18446-P-A, WCAP-16996-P-A, and WCAP-17642-P-A (Proprietary)
Limitations and Conditions Compliance for WCAP-18482-P-A, WCAP-18546-P-A, WCAP-18446-P-A, WCAP-16996-P-A, and WCAP-17642-P-A (Non-Proprietary)
Plant Specific Justification for Application of WCAP-15806-P-A, Revision 0, Westinghouse Control Rod Ejection Accident Analysis Methodology Using Multi-Dimensional Kinetics, November 2003, to Address RG-1.236 (Proprietary)
Plant Specific Justification for Application of WCAP-15806-P-A, Revision 0, Westinghouse Control Rod Ejection Accident Analysis Methodology Using Multi-Dimensional Kinetics, November 2003, to Address RG-1.236 (Non-Proprietary)
Exemption Request for Use of AXIOM Cladding, April 2024 Application for Withholding Proprietary Information from Public Disclosure CAW-25-003 Evaluation of Changes for AST Re-Analysis for an Increase in Fuel Burnup Enclosures 2 and4 to this letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 ULNRC-06922 January 28, 2026 Page 7 of 10
References:
1.
Ameren Missouri Letter ULNRC-06921, "Presentation Information for Pre-Application Meeting Regarding Transition to Advanced Westinghouse Fuel and Upgrade of Analytical Methods at Callaway Plant," dated February 20, 2025 [ADAMS Accession No. ML2525051A346]
NRC letter dated April 29, 2025, "Summary of March 4, 2025, Partially Closed Preapplication Teleconference with Union Electric Company to Discuss Upcoming License Amendment Request (LAR) for the Transition to a New Westinghouse Fuel Type for the Callaway Plant, Unit No. 1 (EPID L2025LRMO0011)" [ADAMS Accession No. ML25099A141 (Package)]
WCAP-16996-P-A, "Realistic LOCA Evaluation Methodology Applied to the Full Spectrum of Break Sizes (FULL SPECTRUM LOCAS Methodology)," Revision 1 [ADAMS Accession Package No. ML16343A238, ML16343A243 (Proprietary)]
WCAP-18482-P-A, "Westinghouse Advanced Doped Pellet Technology (ADOPT') Fuel, Revision 0 [ADAMS Accession Package No. ML22259A187, ML22259A287 (Public),
ML22259A186 (Proprietary)]
WCAP-18546-P-A, "Westinghouse AXIOM Cladding for Use in Pressurized Water Reactor Fuel," Revision 0 [ADAMS Accession Package No. ML23089A066, ML23089A006 (Public),
ML23089A065 (Proprietary)]
WCAP-18446-P-A, "Incremental Extension of Burnup Limit for Westinghouse and Combustion Engineering Fuel Designs," Revision 0 [ADAMS Accession No. ML24227A592]
WCAP-17642-P-A, "Westinghouse Performance Analysis and Design Model (PADS),"
Revision 1 [ADAMS Accession No. ML17338A396 (Public), ML17334A841 (Proprietary)]
WCAP-15806-P-A, "Westinghouse Control Rod Ejection Accident Analysis Methodology Using Multi-Dimensional Kinetics, Revision 0 [ADAMS Accession Package No.
ML033350166, ML0333501747 (Public), ML033350179 (Proprietary)]
Regulatory Guide 1.183, Revision 1, Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Reactors," dated October 2023 Ameren Missouri letter ULNRC-06929, "10 CFR 50.46 Annual Report Regarding ECCS Evaluation Model Revisions," dated March 17, 2025 [ADAMS Accession No. ML25076A043]
STS Change Traveler TSTF-51-A, "Revise containment requirements during handling irradiated fuel and core alterations," Revision 2, dated November 1, 1999 [ADAMS Accession No. ML040400343]
STS Change Traveler TSTF-471-A, "Eliminate use of term CORE ALTERATIONS in ACTIONS and Notes" Revision 1, dated December 18, 2006 [ADAMS Accession No. ML19101A215]
Enclosures 2 and 4 to this letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is
_uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 ULNRC-06922 January 28, 2026 Page 8 of 10 References (continued):
13.
STS Change Traveler TSTF-571-T, "Revise Actions for Inoperable Source Range Neutron Flux Monitor," Revision 0, dated March 14, 2018 [ADAMS Accession No. ML18221A561]
14.
Ameren Missouri Letter ULNRC-06977, "Presentation Information for Pre-Application Meeting Regarding Transition to Advanced Westinghouse Fuel and Upgrade of Analytical Methods at Callaway Plant," dated October 9, 2025 [ADAMS Accession No. ML25282A065 and ML25282A066]
Enclosures2 and4 to this letter contain sensitive information. Withhold from public l disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 ULNRC-06922 January 28, 2026 Page 9 of 10 Mr. John Monninger Regional Administrator U.S. Nuclear Regulatory Commission Region IV 1600 East Lamar Boulevard Arlington, TX 76011-4511 Senior Resident Inspector Callaway Resident Office U.S. Nuclear Regulatory Commission 8201 NRC Road Steedman, MO 65077 Mr. Mahesh Chawla Project Manager, Callaway Plant Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop O8B1A Washington, DC 20555-0001 Enclosures 2 and 4 to this letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 ULNRC-06922 January 28, 2026 Page 10 of 10 Index and send hardcopy to QA File A160.0761 Hardcopy:
Certrec Corporation 6500 West Freeway, Suite 400 Fort Worth, TX 76116 (Certrec receives ALL attachments as long as they are non-safeguards and may be publicly disclosed.)
Electronic distribution for the following can be made via Tech Spec ULNRC Distribution:
K. C. Scott J. G. Beck T. M. Hart T. A. Witt T. B. Elwood B. D. Richardson J. W. Morton NSRB Secretary STARS Regulatory Affairs Mr. Jay Silberg (Pillsbury Winthrop Shaw Pittman LLP)
Ms. Claire Eubanks (Missouri Public Service Commission)
Mr. Aaron Schmidt (DNR)
Enclosures 2 and 4 to this letter contain sensitive information. Withhold from public disclosure under 10 CFR 2.390(a)(4). Upon removal of Enclosures 2 and 4, this letter is
_uncontrolled.
SENSITIVE INFORMATION WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390