ML25351A058
| ML25351A058 | |
| Person / Time | |
|---|---|
| Site: | Byron  |
| Issue date: | 12/18/2025 |
| From: | Michael Ziolkowski NRC/RGN-III/DRSS |
| To: | Mudrick C Constellation Energy Generation, Constellation Nuclear |
| References | |
| IR 2025501 | |
| Download: ML25351A058 (0) | |
Text
Christopher H. Mudrick Senior Vice President Constellation Energy Generation, LLC President and Chief Nuclear Office (CNO)
Constellation Nuclear 200 Energy Way, KSA-3N Kennett Square, PA 19348
SUBJECT:
BYRON STATION - EMERGENCY PREPAREDNESS BIENNIAL EXERCISE INSPECTION REPORT 05000454/2025501 AND 05000455/2025501
Dear Christopher Mudrick:
On December 10, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Byron Station and discussed the results of this inspection with N. Burton and other members of your staff. The results of this inspection are documented in the enclosed report.
No findings or violations of more than minor significance were identified during this inspection.
This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document Room in accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding.
Sincerely, Michael E. Ziolkowski, Chief Security, Emergency Preparedness, and Incident Response Branch Division of Radiological Safety and Security Docket Nos. 05000454 and 05000455 License Nos. NPF-37 and NPF-66
Enclosure:
As stated cc w/ encl: Distribution via LISTSERV December 18, 2025 Signed by Ziolkowski, Michael on 12/18/25
SUNSI Review
Non-Sensitive
Sensitive
Publicly Available
Non-Publicly Available OFFICE RIII/DRSS RIII/DRSS NAME JKutlesa:dc MZiolkowski DATE 12/17/2025 12/18/2025
Enclosure U.S. NUCLEAR REGULATORY COMMISSION Inspection Report Docket Numbers:
05000454 and 05000455 License Numbers:
NPF-37 and NPF-66 Report Numbers:
05000454/2025501 and 05000455/2025501 Enterprise Identifier:
I-2025-501-0009 Licensee:
Constellation Energy Generation, LLC Facility:
Byron Station Location:
Byron, IL Inspection Dates:
August 25, 2025, to December 10, 2025 Inspectors:
J. Kutlesa, Sr Emergency Preparedness Inspector T. McGowan, Emergency Preparedness Inspector Approved By:
Michael E. Ziolkowski, Chief Security, Emergency Preparedness, and Incident Response Branch Division of Radiological Safety and Security
2
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an emergency preparedness biennial exercise inspection at Byron Station, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors.
Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.
List of Findings and Violations No findings or violations of more than minor significance were identified.
Additional Tracking Items None.
3 INSPECTION SCOPES Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection Program - Operations Phase. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.
REACTOR SAFETY 71114.01 - Exercise Evaluation Inspection Review (IP Section 02.01-02.11) (1 Sample)
(1)
The licensee performed a biennial emergency preparedness exercise in accordance with 10 CFR 50 Appendix E(IV)(F)(2)(b), (c), and (j)(iii)(2). This exercise occurred on October 21, 2025, during the 2025 Government Shutdown and, as a result, the inspectors had to review all available documentation to support the evaluation of this exercise per IP 71114.01 and have determined that the licensee has complied with all applicable regulations.
71114.08 - Exercise Evaluation - Scenario Review Inspection Review (IP Section 02.01 - 02.04) (1 Sample)
(1)
The inspectors reviewed and evaluated the proposed scenario for biennial emergency plan exercise on September 3, 2025.
OTHER ACTIVITIES - BASELINE 71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
EP01: Drill/Exercise Performance (DEP) Sample (IP Section 02.12) (1 Sample)
(1)
October 1, 2024, through September 30, 2025 EP02: Emergency Response Organization (ERO) Drill Participation (IP Section 02.13)
(1 Sample)
(1)
October 1, 2024, through September 30, 2025 EP04: Emergency Response Facility and Equipment Readiness (ERFER) (IP Section 02.14)
(1 Sample)
(1)
January 1 through September 30, 2025
4 INSPECTION RESULTS No findings were identified.
EXIT MEETINGS AND DEBRIEFS The inspectors verified no proprietary information was retained or documented in this report.
On December 10, 2025, the inspectors presented the emergency preparedness biennial exercise inspection results to N. Burton and other members of the licensee staff.
5 DOCUMENTS REVIEWED Inspection Procedure Type Designation Description or Title Revision or Date AR 04908329 2025 EP Byron NRC Graded Exercise: TSC DCs 10/23/2025 AR 04908331 2025 EP Byron NRC Graded Exercise: OSC DCs 10/23/2025 AR 04908332 2025 EP Byron NRC Graded Exercise: SIM CR DCs 10/23/2025 AR 04908495 2025 EP Byron NRC Graded Exercise: EOF DCs 10/21/2025 Corrective Action Documents Resulting from Inspection AR 04908497 2025 EP Byron NRC Graded Exercise: JIC DCs 10/24/2025 Byron Draft AAR 11 20 2025 FEMA Byron Generating Station Radiological Emergency Preparedness Exercise Radiological Emergency Preparedness Program Draft After-Action Report/Improvement Plan Exercise Date: October 21, 2025 11/20/2025 Miscellaneous EP-MW-114-100-F-01 Nuclear Accident Reporting System (NARS) Forms for Alert, Site Area Emergency, and General Emergency 10/21/2025 Procedures EP-AA-1002 Radiological Emergency Plan Annex for Byron Station 38 71114.01 Self-Assessments N/A Byron 2025 NRC Graded Exercise Evaluation Report 11/25/2025 EP-AA-1002 Addendum 3 Constellation Emergency Action Levels for Byron Station 6
71114.08 Miscellaneous RS-25-128 Byron Station 2025 NRC Graded Exercise Manual 08/22/2025 LS-AA-2110 Monthly Data Elements for NRC ROP Indicator - Emergency Response Organization (ERO) Drill Participation 10/01/2024 through 09/30/2025 LS-AA-2120 Monthly Data Elements for NRC ROP Indicator -
Drill/Exercise Performance 10/01/2024 through 09/30/2025 71151 Miscellaneous LS-AA-2135 Monthly Data Elements for NRC ROP Indicator - Emergency Response Facility and Equipment Readiness (ERFER) 01/01/2025 through 09/30/2025