ML26020A287
| ML26020A287 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood  |
| Issue date: | 02/04/2026 |
| From: | Scott Wall Plant Licensing Branch III |
| To: | Mudrick C Constellation Energy Generation |
| Wall, S | |
| References | |
| EPID L-2025-LLA-0050 | |
| Download: ML26020A287 (0) | |
Text
February 4, 2026 Mr. Christopher H. Mudrick. Sr.
Senior Vice President Constellation Energy Generation, LLC President and Chief Nuclear Officer Constellation Nuclear 200 Exelon Way Kennett Square, PA 19348
SUBJECT:
BRAIDWOOD STATION, UNITS 1 AND 2; AND BYRON STATION, UNIT NOS. 1 AND 2 - ISSUANCE OF AMENDMENT NOS. 245, 245, 243 AND 243 TO ADOPT TECHNICAL SPECIFICATIONS TASK FORCE TRAVELERS TSTF-286, TSTF-471, AND TSTF-571 (EPID L-2025-LLA-0050)
Dear Mr. Mudrick:
The U.S. Nuclear Regulatory Commission (NRC or Commission) has issued the enclosed amendments (listed below) in response to the Constellation Energy Generation, LLC (CEG) application dated March 14, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25076A032):
- 1.
Amendment No. 245 to Renewed Facility Operating License No. NPF-72 and Amendment No. 245 to Renewed Facility Operating License No. NPF-77 for Braidwood Station, Units 1 and 2, respectively;
- 2.
Amendment No. 243 to Renewed Facility Operating License No. NPF-37 and Amendment No. 243 to Renewed Facility Operating License No. NPF-66 for Byron Station, Unit Nos. 1 and 2, respectively; The amendments revise the technical specifications (TSs) for each facility in accordance with the following Technical Specifications Task Force (TSTF) Travelers:
TSTF-286, Revision 2, Operations Involving Positive Reactivity Additions (ML20106F133). Revises certain TSs to limit the introduction of reactivity into the reactor coolant system (RCS) to be more positive than that required to meet the required shutdown margin (SDM) or refueling boron concentration, as applicable.
TSTF-471, Revision 1, Eliminate use of term CORE ALTERATIONS in ACTIONS and Notes (ML19101A215). Eliminates the remaining uses of the defined term CORE ALTERATIONS. TSTF-471 is a continuation of TSTF-51, Revision 2, Revise containment requirements during handling irradiated fuel and core alterations (ML040400343).
TSTF-571, Revision 0, Revise Actions for Inoperable Source Range Neutron Flux Monitor (pages 6 to 30 of the document in ML18221A561). Revises the Required Actions for an inoperable source range neutron flux monitor to prohibit the movement of fuel assemblies, sources, and reactivity control components when a core subcritical neutron flux monitor is inoperable. A provision is included to allow such movement if it is needed to repair the core subcritical neutron flux monitor.
A copy of the NRC staffs Safety Evaluation is also enclosed. The Notice of Issuance will be included in the Commissions monthly Federal Register notice.
Sincerely,
/RA/
Scott P. Wall, Senior Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos.: STN 50-456, STN 50-457, STN 50-454, and STN 50-455
Enclosures:
- 1. Amendment No. 245 to NPF-72
- 2. Amendment No. 245 to NPF-77
- 3. Amendment No. 243 to NPF-37
- 4. Amendment No. 243 to NPF-66
- 5. Safety Evaluation
- 6. Notices and Environmental Findings cc: Listserv
CONSTELLATION ENERGY GENERATION, LLC DOCKET NO. STN 50-456 BRAIDWOOD STATION, UNIT 1 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 245 Renewed License No. NPF-72
- 1.
The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A.
The application for amendment by Constellation Energy Generation, LLC dated March 14, 2025, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.
There is reasonable assurance: (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D.
The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.
- 2.
Accordingly, the renewed license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-72 is hereby amended to read as follows:
(2)
Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 245 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3.
This license amendment is effective as of the date of its issuance and shall be implemented within 90 days of the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION Ilka T. Berrios, Acting Chief Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Renewed Facility Operating License and Technical Specifications Date of Issuance: February 4, 2026 ILKA BERRIOS Digitally signed by ILKA BERRIOS Date: 2026.02.04 13:04:50 -05'00'
CONSTELLATION ENERGY GENERATION, LLC DOCKET NO. STN 50-457 BRAIDWOOD STATION, UNIT 2 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 245 Renewed License No. NPF-77
- 1.
The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A.
The application for amendment by Constellation Energy Generation, LLC dated March 14, 2025, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.
There is reasonable assurance: (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D.
The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.
- 2.
Accordingly, the renewed license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-77 is hereby amended to read as follows:
(2)
Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 245 and the Environmental Protection Plan contained in Appendix B, both of which are attached to Renewed License No. NPF-72, dated January 27, 2016, are hereby incorporated into the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3.
This license amendment is effective as of the date of its issuance and shall be implemented within 90 days of the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION Ilka T. Berrios, Acting Chief Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Renewed Facility Operating License and Technical Specifications Date of Issuance: February 4, 2026 ILKA BERRIOS Digitally signed by ILKA BERRIOS Date: 2026.02.04 13:05:10 -05'00'
ATTACHMENT TO LICENSE AMENDMENT NOS. 245 AND 245 RENEWED FACILITY OPERATING LICENSE NOS. NPF-72 AND NPF-77 BRAIDWOOD STATION, UNITS 1 AND 2 DOCKET NOS. STN 50-456 AND STN 50-457 Replace the following pages of the Renewed Facility Operating Licenses and Appendix A, Technical Specifications, with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.
Renewed Facility Operating Licenses REMOVE INSERT License NPF-72 License NPF-72 Page 3 Page 3 License NPF-77 License NPF-77 Page 3 Page 3 Technical Specifications REMOVE INSERT REMOVE INSERT 1.1 - 2 1.1 - 2 3.4.18 - 1 3.4.18 - 1 3.3.1 - 5 3.3.1 - 5 3.4.18 - 2 3.4.18 - 2 3.3.1 - 6 3.3.1 - 6 3.8.2 - 2 3.8.2 - 2 3.3.1 - 7 3.3.1 - 7 3.8.2 - 3 3.8.2 - 3 3.4.5 - 1 3.4.5 - 1 3.8.5 - 2 3.8.5 - 2 3.4.5 - 2 3.4.5 - 2 3.8.8 - 2 3.8.8 - 2 3.4.5 - 3 3.4.5 - 3 3.8.10 - 3 3.8.10 - 3 3.4.6 - 1 3.4.6 - 1 3.9.1 - 1 3.9.1 - 1 3.4.6 - 2 3.4.6 - 2 3.9.2 - 1 3.9.2 - 1 3.4.7 - 1 3.4.7 - 1 3.9.3 - 1 3.9.3 - 1 3.4.7 - 2 3.4.7 - 2 3.9.5 - 1 3.9.5 - 1 3.4.7 - 3 3.4.7 - 3 3.9.6 - 2 3.9.6 - 2 3.4.7 - 4 3.4.7 - 4 3.9.6 - 3 3.4.8 - 1 3.4.8 - 1 3.4.8 - 2 3.4.8 - 2 Renewed License No. NPF-72 Amendment No. 245 (2)
Constellation Energy Generation, LLC, pursuant to the Act and 10 CFR Part 70, to receive, possess and use at any time special nuclear material as reactor fuel, in accordance with the limitations for storage and amounts required for reactor operation, as described in the Final Safety Analysis Report, as supplemented and amended; (3)
Constellation Energy Generation, LLC, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use at any time any byproduct, source and special nuclear material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required; (4)
Constellation Energy Generation, LLC, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required any byproduct, source or special nuclear material without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; and (5)
Constellation Energy Generation, LLC, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.
C.
This renewed license shall be deemed to contain and is subject to the conditions specified in the Commissions regulations set forth in 10 CFR Chapter I and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect; and is subject to the additional conditions specified or incorporated below:
(1)
Maximum Power Level The licensee is authorized to operate the facility at reactor core power levels not in excess of 3645 megawatts thermal (100 percent rated power) in accordance with the conditions specified herein.
(2)
Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 245 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
Renewed License No. NPF-77 Amendment No. 245 (2)
Constellation Energy Generation, LLC, pursuant to the Act and 10 CFR Part 70, to receive, possess and use at any time special nuclear material as reactor fuel, in accordance with the limitations for storage and amounts required for reactor operation, as described in the Final Safety Analysis Report, as supplemented and amended; (3)
Constellation Energy Generation, LLC, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use at any time any byproduct, source and special nuclear material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required; (4)
Constellation Energy Generation, LLC, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required any byproduct, source or special nuclear material without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; and (5)
Constellation Energy Generation, LLC, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.
C.
The renewed license shall be deemed to contain and is subject to the conditions specified in the Commissions regulations set forth in 10 CFR Chapter I and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect; and is subject to the additional conditions specified or incorporated below:
(1)
Maximum Power Level The licensee is authorized to operate the facility at reactor core power levels not in excess of 3645 megawatts thermal (100 percent rated power) in accordance with the conditions specified herein.
(2)
Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 245 and the Environmental Protection Plan contained in Appendix B, both of which are attached to Renewed License No. NPF-72, dated January 27, 2016, are hereby incorporated into the renewed license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
ACTIONS (continued)
CONDITION F. One Intermediate Range Neutron Flux channel inoperable.
G. Two Intermediate Range Neutron Flux channels inoperable.
H. One Source Range Neutron Flux channel inoperable.
I. Two Source Range Neutron Flux channels inoperable.
BRAIDWOOD - UNITS 1 & 2 REQU I RED ACTION F.1 Reduce THERMAL POWER to< P-6.
OR F.2 Increase THERMAL POWER to> P-10.
NOTE------------
Limited plant cooldown or boron dilution is allowed provided the change is accounted for in the calculated SOM.
G.1 Suspend operations involving positive reactivity additions.
AND G.2 Reduce THERMAL POWER to< P-6.
NOTE------------
Limited plant cooldown or boron dilution is allowed provided the change is accounted for in the calculated SOM.
H.1 Suspend operations involving positive reactivity additions.
I.1 Open Reactor Trip Breakers (RTBs).
3.3.1 - 5 RTS Instrumentation 3.3.1 COMPLETION TIME 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 24 hours Immediately 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> Immediately Immediately Amendment 245 (continued)
ACTIONS (continued)
CONDITION REQU I RED ACTION J. One Source Range J.1 Restore channel to Neutron Flux channel OPERABLE status.
OR J.2.1 Initiate action to fully insert all rods.
AND J.2.2 Place the Rod Control System in a condition incapable of rod withdrawal.
K. One channel
NOTES------------
1.
For Functions with installed bypass test capability (Functions Ba, 9, 10), one channel may be bypassed for up to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for surveillance testing.
- 2. For Functions with no installed bypass test capability (Functions 12 and 13), the inoperable channel may be bypassed for up to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for surveillance testing of other channels.
K.1 Place channel in trip.
BRAIDWOOD - UNITS 1 & 2 3.3.1 - 6 RTS Instrumentation 3.3.1 COMPLETION TIME 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> 48 hours 49 hours5.671296e-4 days <br />0.0136 hours <br />8.101852e-5 weeks <br />1.86445e-5 months <br /> 72 hours OR In accordance with the Risk Informed Completion Time Program (continued)
Amendment 245
ACTIONS (continued)
CONDITION L. Required Action and associated Completion Time of Condition K not met.
M. One Turbine Trip channel inoperable.
N.
Required Action and associated Completion Time of Condition M not met.
BRAIDWOOD - UNITS 1 & 2 REQU I RED ACTION L.1 Reduce THERMAL POWER to< P-7.
NOTE-------------
The inoperable channel may be bypassed for up to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for surveillance testing of other channels.
M.1 Place channel in trip.
N.1 Reduce THERMAL POWER to< P-8.
3.3.1 - 7 RTS Instrumentation 3.3.1 COMPLETION TIME 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 72 hours OR In accordance with the Risk Informed Completion Time Program 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> (continued)
Amendment 245
ACTIONS CONDITION A. No required RHR loop A.1 in operation.
AND A.2 B. One required RHR loop B.1 inoperable.
C.
One or both required C.1 SG secondary side water level(s) not within limits.
BRAIDWOOD -UNITS 1 & 2 RCS Loops-MODE 5, Loops Filled 3.4. 7 REQU I RED ACTION COMPLETION TIME Suspend operations Immediately that would cause introduction of coolant into the RCS with boron concentration less than required to meet the SOM of LCO 3.1.1.
Initiate action to Immediately restore one RHR loop to operation.
Initiate action to Immediately restore required RHR loop to OPERABLE status.
Initiate action to Immediately restore required SG secondary side water level(s) to within limits.
(continued) 3.4.7-2 Amendment 245
RCS Loops-MODE 5, Loops Filled 3.4. 7 ACTIONS (continued)
CONDITION REQU I RED ACTION D. Two required RHR loops D.1 Suspend operations inoperable.
that would cause introduction of OR coolant into the RCS with boron Required RHR loop concentration less inoperable and one or than required to meet both required SG the SOM of LCO 3.1.1.
secondary side water level(s) not within AND limits.
D.2.1 Initiate action to restore one RHR loop to OPERABLE status.
OR D.2.2 Initiate action to restore required SG secondary side water level(s) to within limits.
SURVEILLANCE REQUIREMENTS SURVEILLANCE SR 3.4. 7.1 SR 3.4.7.2 Verify required RHR loop is in operation.
Verify SG secondary side narrow range water level is> 18% in required SGs.
BRAIDWOOD -UNITS 1 & 2 3.4.7-3 COMPLETION TIME Immediately Immediately Immediately FREQUENCY In accordance with the Surveillance Frequency Control Program In accordance with the Surveillance Frequency Control Program Amendment 245 (continued)
RCS Loops-MODE 5, Loops Filled 3.4. 7 SURVEILLANCE REQUIREMENTS (continued)
SR 3.4. 7.3 SR 3.4. 7.4 Verify correct breaker alignment and indicated power are available to each required RHR pump that is not in operation.
Verify required RHR loop locations susceptible to gas accumulation are sufficiently filled with water.
BRAIDWOOD -UNITS 1 & 2 3.4.7-4 In accordance with the Surveillance Frequency Control Program In accordance with the Surveillance Frequency Control Program Amendment 245
RHR and Coolant Circulation-High Water Level 3.9.5 3.9 REFUELING OPERATIONS 3.9.5 Residual Heat Removal (RHR) and Coolant Circulation-High Water Level LCO 3.9.5 One RHR loop shall be OPERABLE and in operation.
NOTE----------------------------
The required RHR loop may be removed from operation for
= 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> per 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period, provided no operations are permitted that would cause introduction of coolant into the Reactor Coolant System with boron concentration less than that required to meet the minimum required boron concentration of LCO 3.9.1.
APPLICABILITY:
MODE 6 with the water level> 23 ft above the top of reactor vessel flange.
ACTIONS CONDITION A. RHR loop requirements A.1 not met.
AND A.2 AND A.3 AND BRAIDWOOD - UNITS 1 & 2 REQU I RED ACTION COMPLETION TIME Suspend operations Immediately that would cause introduction of coolant into the RCS with boron concentration less than required to meet the boron concentration of LCO 3.9.1.
Suspend loading Immediately irradiated fuel assemblies in the core.
Initiate action to Immediately satisfy RHR loop requirements.
(continued) 3.9.5 - 1 Amendment 245
RHR and Coolant Circulation-Low Water Level 3.9.6 ACTIONS (continued)
CONDITION REQU I RED ACTION B. No RHR loop in B.1 Suspend operations operation.
that would cause introduction of coolant into the RCS with boron concentration less than required to meet the boron concentration of LCO 3.9.1.
AND B.2 Initiate action to restore one RHR loop to operation.
AND B.3 Close all containment penetrations providing direct access from containment atmosphere to outside atmosphere.
SURVEILLANCE REQUIREMENTS SR 3.9.6.1 SR 3.9.6.2 SURVEILLANCE Verify one RHR loop is in operation and circulating reactor coolant at a flow rate of< 1000 gpm.
Verify correct breaker alignment and indicated power available to the required RHR pump that is not in operation.
BRAIDWOOD - UNITS 1 & 2 3.9.6 - 2 COMPLETION TIME Immediately Immediately 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> FREQUENCY In accordance with the Surveillance Frequency Control Program In accordance with the Surveillance Frequency Control Program Amendment 245 (continued)
SR 3.9.6.3 RHR and Coolant Circulation-Low Water Level 3.9.6 SURVEILLANCE Verify RHR loop locations susceptible to gas accumulation are sufficiently filled with water.
FREQUENCY In accordance with the Surveillance Frequency Control Program BRAIDWOOD - UNITS 1 & 2 3.9.6 - 3 Amendment 245 SURVEILLANCE REQUIREMENTS (continued)
CONSTELLATION ENERGY GENERATION, LLC DOCKET NO. STN 50-454 BYRON STATION, UNIT NO. 1 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 243 Renewed License No. NPF-37
- 1.
The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A.
The application for amendment by Constellation Energy Generation, LLC dated March 14, 2025, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.
There is reasonable assurance: (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D.
The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.
- 2.
Accordingly, the renewed license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-37 is hereby amended to read as follows:
(2)
Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 243 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this renewed license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3.
This license amendment is effective as of the date of its issuance and shall be implemented within 90 days of the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION Ilka T. Berrios, Acting Chief Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Renewed Facility Operating License and Technical Specifications Date of Issuance: February 4, 2026 ILKA BERRIOS Digitally signed by ILKA BERRIOS Date: 2026.02.04 13:34:54 -05'00'
CONSTELLATION ENERGY GENERATION, LLC DOCKET NO. STN 50-455 BYRON STATION, UNIT NO. 2 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 243 Renewed License No. NPF-66
- 1.
The U.S. Nuclear Regulatory Commission (the Commission) has found that:
A.
The application for amendment by Constellation Energy Generation, LLC dated March 14, 2025, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B.
The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C.
There is reasonable assurance: (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D.
The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.
- 2.
Accordingly, the license is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and paragraph 2.C.(2) of Renewed Facility Operating License No. NPF-66 is hereby amended to read as follows:
(2)
Technical Specifications The Technical Specifications contained in Appendix A (NUREG-1113), as revised through Amendment No. 243, and the Environmental Protection Plan contained in Appendix B, both of which were attached to Renewed License No. NPF-37, dated November 19, 2015, are hereby incorporated into this renewed license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
- 3.
This license amendment is effective as of the date of its issuance and shall be implemented within 90 days of the date of issuance.
FOR THE NUCLEAR REGULATORY COMMISSION Ilka T. Berrios, Acting Chief Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Attachment:
Changes to the Renewed Facility Operating License and Technical Specifications Date of Issuance: February 4, 2026 ILKA BERRIOS Digitally signed by ILKA BERRIOS Date: 2026.02.04 13:35:15 -05'00'
ATTACHMENT TO LICENSE AMENDMENT NOS. 243 AND 243 RENEWED FACILITY OPERATING LICENSE NOS. NPF-37 AND NPF-66 BYRON STATION, UNIT NOS. 1 AND 2 DOCKET NOS. STN 50-454 AND STN 50-455 Replace the following pages of the Renewed Facility Operating Licenses and Appendix A, Technical Specifications, with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.
Renewed Facility Operating Licenses REMOVE INSERT License NPF-37 License NPF-37 Page 3 Page 3 License NPF-66 License NPF-66 Page 3 Page 3 Technical Specifications REMOVE INSERT 1.1 - 2 1.1 - 2 3.3.1 - 4 3.3.1 - 4 3.4.5 - 1 3.4.5 - 1 3.4.5 - 2 3.4.5 - 2 3.4.5 - 3 3.4.5 - 3 3.4.6 - 1 3.4.6 - 1 3.4.6 - 2 3.4.6 - 2 3.4.7 - 1 3.4.7 - 1 3.4.7 - 2 3.4.7 - 2 3.4.7 - 3 3.4.7 - 3 3.4.8 - 1 3.4.8 - 1 3.4.8 - 2 3.4.8 - 2 3.4.18 - 1 3.4.18 - 1 3.4.18 - 2 3.4.18 - 2 3.8.2 - 2 3.8.2 - 2 3.8.2 - 3 3.8.2 - 3 3.8.5 - 2 3.8.5 - 2 3.8.8 - 2 3.8.8 - 2 3.8.10 - 3 3.8.10 - 3 3.9.1 - 1 3.9.1 - 1 3.9.2 - 1 3.9.2 - 1 3.9.3 - 1 3.9.3 - 1 3.9.5 - 1 3.9.5 - 1 3.9.6 - 2 3.9.6 - 2 Renewed License No. NPF-37 Amendment No. 243 (2)
Pursuant to the Act and 10 CFR Part 70, to receive, possess and use at any time special nuclear material as reactor fuel, in accordance with the limitations for storage and amounts required for reactor operation, as described in the Updated Final Safety Analysis Report, as supplemented and amended; (3)
Pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use at any time any byproduct, source and special nuclear material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required; (4)
Pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required any byproduct, source or special nuclear material without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; and (5)
Pursuant to the Act and 10 CFR Parts 30, 40 and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.
C.
The renewed license shall be deemed to contain and is subject to the conditions specified in the Commissions regulations set forth in 10 CFR Chapter I and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect; and is subject to the additional conditions specified or incorporated below:
(1)
Maximum Power Level The licensee is authorized to operate the facility at reactor core power levels not in excess of 3645 megawatts thermal (100 percent rated power) in accordance with the conditions specified herein.
(2)
Technical Specifications The Technical Specifications contained in Appendix A as revised through Amendment No. 243 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this renewed license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3)
Deleted.
(4)
Deleted.
Renewed License No. NPF-66 Amendment No. 243 (2)
Pursuant to the Act and 10 CFR Part 70, to receive, possess and use at any time special nuclear material as reactor fuel, in accordance with the limitations for storage and amounts required for reactor operation, as described in the Updated Final Safety Analysis Report, as supplemented and amended; (3)
Pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use at any time any byproduct, source and special nuclear material as sealed neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required; (4)
Pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required any byproduct, source or special nuclear material without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; and (5)
Pursuant to the Act and 10 CFR Parts 30, 40 and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.
C.
The renewed license shall be deemed to contain and is subject to the conditions specified in the Commissions regulations set forth in 10 CFR Chapter I and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect; and is subject to the additional conditions specified or incorporated below:
(1)
Maximum Power Level The licensee is authorized to operate the facility at reactor core power levels not in excess of 3645 megawatts thermal (100 percent rated power) in accordance with the conditions specified herein.
(2)
Technical Specifications The Technical Specifications contained in Appendix A (NUREG-1113), as revised through Amendment No. 243, and the Environmental Protection Plan contained in Appendix B, both of which were attached to Renewed License No. NPF-37, dated November 19, 2015, are hereby incorporated into this renewed license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.
(3)
Deleted.
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 245 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-72 AMENDMENT NO. 245 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-77 AMENDMENT NO. 243 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-37 AMENDMENT NO. 243 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-66 CONSTELLATION ENERGY GENERATION, LLC BRAIDWOOD STATION, UNITS 1 AND 2 BYRON STATION, UNIT NOS. 1 AND 2 DOCKET NOS. STN 50-456, STN 50-457, STN 50-454, AND STN 50-455 Application (i.e., initial and supplements)
Safety Evaluation Date March 14, 2025, ML25076A032 February 4, 2026 Principal Contributors to Safety Evaluation Mark Schwieg Khadijah West
1.0 INTRODUCTION
Constellation Energy Generation, LLC (CEG, the licensee) requested changes to the technical specifications (TSs) for Braidwood Station, Units 1 and 2 (Braidwood); and Byron Station, Unit Nos. 1 and 2 (Byron), by license amendment request (LAR, application). The amendments revise the TSs for each facility in accordance with the following Technical Specifications Task Force (TSTF) Travelers:
TSTF-286, Revision 2, Operations Involving Positive Reactivity Additions (ML20106F133). Revises certain TSs to limit the introduction of reactivity into the reactor coolant system (RCS) to be more positive than that required to meet the required shutdown margin (SDM) or refueling boron concentration, as applicable.
TSTF-471, Revision 1, Eliminate use of term CORE ALTERATIONS in ACTIONS and Notes (ML19101A215). Eliminates the remaining uses of the defined term CORE ALTERATIONS. TSTF-471 is a continuation of TSTF-51, Revision 2, Revise containment requirements during handling irradiated fuel and core alterations (ML040400343).
TSTF-571, Revision 0, Revise Actions for Inoperable Source Range Neutron Flux Monitor (pages 6 to 30 of the document in ML18221A561). Revises the Required Actions for an inoperable source range neutron flux monitor to prohibit the movement of fuel assemblies, sources, and reactivity control components when a core subcritical neutron flux monitor is inoperable. A provision is included to allow such movement if it is needed to repair the core subcritical neutron flux monitor.
1.1 Proposed TS Changes to Adopt TSTF-286, TSTF-471 and TSTF-571 The following revisions were proposed for the TS for Braidwood and Byron:
TS 1.1, Definitions The defined term CORE ALTERATION will be deleted.
TS 3.3.1, Reactor Trip System (RTS) Instrumentation A Note will be added before Required Actions G.1 and H.1 that reads, "[l]imited plant cooldown or boron dilution is allowed provided the change is accounted for in the calculated SDM."
TS 3.4.5, RCS Loops - MODE 3, TS 3.4.6, RCS Loops - MODE 4, TS 3.4.7, RCS Loops -
MODE 5, Loops Filled, and 3.4.8, RCS Loops - MODE 5, Loops Not Filled Limiting condition for operation (LCO) Note 1a. will be changed from "[n]o operations are permitted that would cause reduction of the RCS boron concentration; " to "[n]o operations are permitted that would cause introduction of coolant into the RCS with boron concentration less than required to meet the SDM of LCO 3.1.1 [Shutdown Margin (SDM)]; "
The following Required Actions will be changed from [s]uspend all operations involving a reduction in RCS boron concentration to [s]uspend operations that would cause introduction of coolant into the RCS with boron concentration less than required to meet the SDM of LCO 3.1.1:
o TS 3.4.5 Required Actions B.1, C.2, and F.2; o TS 3.4.6 Required Actions A.1 and C.1; o TS 3.4.7 Required Actions A.1 and D.1; and o TS 3.4.8 Required Actions A.1 and C.1.
Required Action A.1 of TS 3.4.6 and 3.4.7, and Required Action C.1 of TS 3.4.6 and TS 3.4.8 will be changed from [s]uspend all operations involving a reduction in RCS boron concentration to [s]uspend operations that would cause introduction of coolant into the RCS with boron concentration less than required to meet the SDM of LCO 3.1.1.
Required Actions B.1, C.2, and F.2 of TS 3.4.5 and Required Action D.1 of TS 3.4.7 will be changed from Suspend all operations involving a reduction of RCS boron concentration to Suspend operations that would cause introduction of coolant into the RCS with boron concentration less than required to meet SDM of LCO 3.1.1.
TS 3.4.18, RCS Loops - Isolated LCO 3.4.18.a will be changed, in part, from "required SDM boron concentration of the unisolated portion of the RCS" to "...boron concentration required to meet the SDM of LCO 3.1.1 or boron concentration of LCO 3.9.1 [Boron Concentration]"
SR 3.4.18.2 will be changed, in part, from "required SDM boron concentration of the unisolated portion of the RCS" to "boron concentration required to meet the SDM of LCO 3.1.1or boron concentration of LCO 3.9.1".
TS 3.8.2, AC Sources - Shutdown, TS 3.8.5, DC Sources - Shutdown, TS 3.8.8, Inverters, and 3.8.10, Distribution Systems - Shutdown Required Action A.2.1 "Suspend CORE ALTERATIONS," will be deleted and subsequent Required Action numbers will be changed.
Current Required Action A.2.3 (new A.2.2) will be changed from "[i]nitiate action to suspend operations involving positive reactivity additions," to "[s]uspend operations involving positive reactivity additions that could result in loss of required SDM or boron concentration."
For TS 3.8.2 only, the above changes to A.2.1 and new A.2.2 will be applied to Required Actions B.1 and B.3 (new B.2), respectively.
TS 3.9.1, Boron Concentration, and TS 3.9.2, Unborated Water Source Isolation Valves Required Action A.1, "Suspend CORE ALTERATIONS," will be deleted and subsequent Required Action numbers will be changed. An associated change in TS 3.9.2 Condition A NOTE will change reference from Required Action A.3 to A.2.
TS 3.9.3, Nuclear Instrumentation Required Action A.1, "[s]uspend CORE ALTERATIONS," will be changed to "[s]uspend positive reactivity additions."
Required Action A.2, "[s]uspend positive reactivity additions, will be changed to
"[s]uspend movement of fuel, sources, and reactivity control components within the reactor vessel." Additionally, a Note above Required Action A.2 will state, "[f]uel assemblies, sources, and reactivity control components may be moved if necessary to restore an inoperable source range neutron flux monitor or to complete movement of a component to a safe condition."
TS 3.9.5, Residual Heat Removal (RHR) and Coolant Circulation-High Water Level, and TS 3.9.6, RHR and Coolant Circulation-Low Water Level LCO Note will change, in part, from "reduction of the Reactor Coolant System boron concentration" to "introduction of coolant into the Reactor Coolant System with boron concentration less than that required to meet the minimum required boron concentration of LCO 3.9.1."
Required Actions A.1 and B.1 will change from "[s]uspend operations involving a reduction in reactor coolant boron concentration" to "[s]uspend operations that would cause introduction of coolant into the RCS with boron concentration less than required to meet the boron concentration of LCO 3.9.1."
1.2 Proposed Changes to Technical Specification Bases Consistent with Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36(a)(1), the licensee submitted corresponding changes to the TS Bases, for information only, that provide the reasons for the proposed TSs changes. The regulation at 10 CFR 50.36(a)(1) states that a summary statement of the bases or reasons for such specifications, other than those covering administrative controls, shall also be included in the application, but shall not become part of the TS. The licensee shall make changes to the plant TS Bases in accordance with the TS Bases Control Program, found at TS 5.5.14 for Braidwood and Byron.
2.0 REGULATORY EVALUATION
2.1 Regulatory Requirements Per 10 CFR 50.90, whenever a holder of a license wishes to amend the license, including technical specifications in the license, an application for amendment must be filed, fully describing the changes desired. Under 10 CFR Part 50.92(a), determinations on whether to grant an applied-for license amendment are to be guided by the considerations that govern the issuance of initial licenses or construction permits to the extent applicable and appropriate. Both the common standards for licenses and construction permits in 10 CFR Part 50.40(a), and those specifically for issuance of operating licenses in 10 CFR Part 50.57(a)(3), provide that there must be reasonable assurance that the activities at issue will not endanger the health and safety of the public.
The categories of items required to be in the TSs are listed in 10 CFR 50.36(c). The regulation at 10 CFR 50.36(c)(2) requires that TSs include LCOs. Per 10 CFR 50.36(c)(2)(i), LCOs are the lowest functional capability or performance levels of equipment required for safe operation of the facility. The regulation also requires that when an LCO of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the TS until the condition can be met.
The regulation at 10 CFR 50.36(c)(3) requires that TSs include items in the category of SRs, which are requirements relating to test, calibration, or inspection to assure that the necessary quality of systems and components is maintained, that facility operation will be within safety limits, and that the LCOs will be met.
2.2 Regulatory Guidance The NRC staffs guidance for the review of TSs is in Chapter 16.0, Technical Specifications, of NUREG-0800, Revision 3, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR [Light-Water Reactor] Edition (SRP), March 2010 (ML100351425).
An NRC letter addressed to the TSTF contained the NRC staffs resolution of concerns regarding potential operating issues in plant-specific implementation of TSTF-51, Revision 2; TSTF-471, Revision 1; and TSTF-286, Revision 2. An NRC letter addressed to the TSTF dated November 7, 2013 (ML13246A358), documented the staffs initial concerns, which were later resolved in the letter dated October 4, 2018 (ML17346A587). The letter dated October 4, 2018, contains descriptions of additional radiological information or analysis that licensees should include in applications to support review and adoption of these travelers.
TSTF-286, Operations Involving Positive Reactivity Additions, was approved by an NRC letter dated July 6, 2000 (ML003730788). TSTF-286 changes the standard TS (STS) by providing the flexibility necessary to provide for continued safe reactor operations, while also limiting any potential for excess positive reactivity addition. (NRC staff concerns with TSTF-286 led to the development of TSTF-571.)
Travelers TSTF-286, TSTF-471, and TSTF-571 provide acceptable methods of modifying core monitoring instrumentation and dose consequences requirements contained in the STS. Though TSTF-286, TSTF-471, and TSTF-571 were developed based on changes to NUREG-1431, Standard Technical Specifications, Westinghouse Plants, Revisions 1, 3, and 4, respectively, the NRC staffs review of this LAR includes consideration of whether the proposed changes are consistent with the latest revision, Revision 5. Volume 1, Specifications, of Revision 5 (ML21259A155), provides example TS LCOs and acceptable remedial actions that meet the requirements in 10 CFR 50.36(c)(2)(i) for a standard plant design.
3.0 TECHNICAL EVALUATION
3.1 Evaluation of Proposed TSTF-286 TS Changes The licensee proposed to revise TS Required Actions and Notes consistent with TSTF-286 that currently mandate suspension of operations involving positive reactivity additions or reductions in boron concentration. The revised language permits such operations, provided they do not reduce the SDM or refueling boron concentration below required limits. Accordingly, the licensee stated in the LAR that, [a]ll current safety analyses remain valid and unchanged with the introduction of these changes The NRC approval of TSTF-286 is based on the need to support continued safe reactor operations without imposing unnecessary restrictions. Essential activities such as RCS inventory management and temperature control may involve the addition of cooler water or makeup sources with lower boron concentrations. These activities, when performed within the limits that maintain SDM or refueling boron concentration, do not compromise safety and should not be precluded by TS. Furthermore, tracking operability of equipment not credited in accident analyses during core alterations offers no benefit of safety. The NRC staff determined that the proposed changes would allow such normal operations to continue without violating safety requirements.
Reactivity control is maintained through two independent systems: the control and shutdown rods, and the Chemical and Volume Control System, which adjusts soluble boron concentration.
These systems are used across all operating modes to manage reactivity changes due to fuel temperature, coolant temperature, and reactor poisons. In Modes 1 through 4, the minimum required SDM is a key assumption in safety analyses, ensuring that specified acceptable fuel design limits are not exceeded during normal operation and anticipated operational occurrences, even with the highest worth control rod stuck out. The most limiting events for establishing SDM and boron concentration requirements are the main steam line break and boron dilution accidents.
The NRC staff reviewed the licensees proposed changes to revise certain TSs and determined they were consistent with TSTF-286. The proposed changes would limit the introduction of reactivity into the RCS to be more positive than that required to meet the required SDM or refueling boron concentration. Therefore, the NRC staff finds that the proposed changes acceptable because they continue to meet the regulatory requirements of 10 CFR 50.36(c)(2)(i).
The revised TS will continue to maintain the SDM and boron concentrations within limits and describe the lowest functional capability or performance level of equipment necessary for the safe operation of the facility. Furthermore, the proposed remedial actions provide reasonable assurance that the plant will remain in a safe condition until the LCO can be met.
3.2 Evaluation of Proposed TSTF-471 TS Changes TSTF-471 eliminates the defined term core alterations and its usage from the TS.
Previously, core alterations was defined as the movement of any fuel, sources, or reactivity control components within the reactor vessel, with the vessel head removed and fuel present.
The definition also clarified that suspension of core alternations does not preclude completing the movement of a component to a safe position. The defined term appears in several Required Actions and Surveillance Notes.
When the reactor vessel head is unbolted and removed, core alterations take place during operating Mode 6 (refueling operation). There are only two accidents considered during Mode 6.
These accidents are: (1) a fuel handling accident (FHA), and (2) a boron dilution accident. An FHA is initiated by the dropping of an irradiated fuel assembly, either in the containment or in the spent fuel pool. There are no mitigation actions, except for taking credit for ventilation systems to reduce the dose consequences. Thus, the suspension of core alterations, except for suspension of movement of irradiated fuel, will not prevent or impair the mitigation of an FHA.
The analysis for an FHA assumes that a fuel assembly is dropped during fuel handling in the containment or the spent fuel pool. Interlocks and procedural, and administrative controls make such an event highly unlikely. However, if an assembly were damaged to the extent that one or more fuel rods were broken, the accumulated fission product gases and iodines in the fuel element gap would be released to the surrounding water. Release of the solid fission products in the fuel would be negligible because of the low fuel temperature during refueling, which greatly limits their diffusion.
A boron dilution accident is initiated by a dilution source that results in the boron concentration dropping below the value required to maintain the shutdown margin. TS 3.9.1 applies in Mode 6, and the refueling boron concentration limit is specified in the core operating limits report. This accident is mitigated by stopping the dilution. The suspension of core alterations has no effect on the mitigation of a boron dilution accident. Also, the control rods or fuel do not affect the initial conditions of a boron dilution accident.
In the NRC letter to the TSTF dated October 4, 2018, the NRC staff states, in part:
After considerable review and analysis, the NRC staff concludes that for certain facilities, LARs adopting TSTF-51 and TSTF-471 could result in exceeding the bounding licensing basis Fuel Handling Accident (FHA) analysis of record dose for the control room and is therefore considered an unanalyzed condition.
In this letter, the NRC staff determined that following approval of LARs to adopt TSTF-51 and TSTF-471, the containment purge and exhaust isolation instrumentation and the containment penetrations will no longer require to be operable during core alterations. The NRC staff identified that dropping a source, fuel assembly, or component during core alterations could damage a recently irradiated fuel assembly, thereby creating a radioactive source term that may result in exceeding the resultant radiological doses calculated by the licensing basis FHA analysis of record. Therefore, the NRC staff recommended in the October 4, 2018, letter that when licensees request to adopt TSTF-51 and TSTF-471, one of four discussions be provided to support removal of the defined term core alterations from the TS applicability. The licensee provided a confirmation that the length of time defined as recently is less than the time required to remove the reactor vessel head and internals and expose the irradiated fuel after a shutdown.
In the current LAR, the licensee stated in section 2.1 that as part of the adoption of TSTF-51, a new defined term was added to TS, RECENTLY IRRADIATED FUEL (i.e., fuel that has occupied part of a critical reactor core within the previous 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.) This was approved by NRC on September 8, 2006, for Byron and Braidwood in License Amendment Nos.147 and 140 (ML062340420).
As a result, the NRC staff has determined that, during core alterations, an FHA will not damage an irradiated fuel assembly. Without the creation of a radioactive source term from a core alterations event, the radiological doses will remain bounded by the current FHA which assumes the FHA will occur 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after plant shutdown. In the LAR, the licensee has addressed the staffs concerns with adoption of TSTF-471. Therefore, the NRC staff finds acceptable the proposed changes consistent with TSTF-471 because they meet 10 CFR 50.36(c)(2); and the revised TS applicability, conditions, and remedial actions will allow for safe operation of the plant.
3.3 Evaluation of Proposed TSTF-571 TS Changes In a letter to the TSTF dated November 7, 2013, the NRC staff raised concerns regarding the TSTF-286 changes to Required Actions in the Nuclear Instrumentation specification when one source range neutron flux monitor is inoperable. The concernreferred to as the decouple effectis that during movement of fuel assemblies, sources, or reactivity control components, the remaining operable monitor may become effectively decoupled from the cores reactivity condition. For example, if one monitor is inoperable and certain strategically located fuel assemblies are removed, the operable monitor may no longer provide an accurate indication of reactivity in portions of the core. As a result, the TSTF-286 changes could create a condition in which a reactivity increase might go undetected.
The NRC later determined and informed the TSTF (by letter dated October 4, 2018) that the NRC staffs concerns regarding the Nuclear Instrumentation would be adequately addressed provided that licensees adopt traveler TSTF-571 when adopting TSTF-286. In this request, CEG proposed adopting TSTF-571, which revises TS 3.9.3, Required Action A.2. The revised action would state: Suspend movement of fuel, sources, and reactivity control components within the reactor vessel, and would be accompanied by a note allowing such movement if necessary to restore an inoperable source range neutron flux monitor or to complete movement of a component to a safe condition.
The NRC staff concluded that the proposed changes are consistent with TSTF-571 and ensure that no actions are taken that could add positive reactivity additions when a source range neutron flux monitor is inoperable. In addition, the action in the proposed TS change would suspend movement of any fuel, sources, and reactivity control components that may affect reactivity until the source range neutron flux monitor is restored. The proposed Note would allow the licensee to move the move fuel assemblies, sources and reactivity control components if necessary to restore an inoperable source range neutron flux monitor or to complete movement of a component to a safe position.
Therefore, the NRC staff finds that the proposed changes acceptable, consistent with TSTF-571 and continue to meet the regulatory requirements of 10 CFR 50.36(c)(2). The revised TS will continue to describe the lowest functional capability or performance level of equipment necessary for the safe operation of the facility. Furthermore, the proposed remedial actions provide reasonable assurance that the plant will remain in a safe condition until the LCO can be met.
3.4 TS Change Consistency The NRC staff reviewed the proposed TS changes for technical clarity and consistency with the existing requirements for customary terminology and formatting. The NRC staff finds that the proposed changes are consistent with chapter 16.0 of the SRP and are therefore acceptable.
4.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) there is reasonable assurance that 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.
NOTICES AND ENVIRONMENTAL FINDINGS RELATED TO AMENDMENT NO. 245 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-72 AMENDMENT NO. 245 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-77 AMENDMENT NO. 243 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-37 AMENDMENT NO. 243 TO RENEWED FACILITY OPERATING LICENSE NO. NPF-66 CONSTELLATION ENERGY GENERATION, LLC BRAIDWOOD STATION, UNITS 1 AND 2 BYRON STATION, UNIT NOS. 1 AND 2 DOCKET NOS. STN 50-456, STN 50-457, STN 50-454, AND STN 50-455 Application (i.e., initial and supplements)
Safety Evaluation Date March 14, 2025, ML25076A032 February 4, 2026
1.0 INTRODUCTION
Constellation Energy Generation, LLC (CEG, the licensee) requested changes to the technical specifications (TSs) for Braidwood Station, Units 1 and 2 (Braidwood); and Byron Station, Unit Nos. 1 and 2 (Byron), by license amendment request (LAR, application). The amendments revise the TSs for each facility in accordance with the following Technical Specifications Task Force (TSTF) Travelers:
TSTF-286, Revision 2, Operations Involving Positive Reactivity Additions (ML20106F133). Revises certain TSs to limit the introduction of reactivity into the reactor coolant system (RCS) to be more positive than that required to meet the required shutdown margin (SDM) or refueling boron concentration, as applicable.
TSTF-471, Revision 1, Eliminate use of term CORE ALTERATIONS in ACTIONS and Notes (ML19101A215). Eliminates the remaining uses of the defined term CORE ALTERATIONS. TSTF-471 is a continuation of TSTF-51, Revision 2, Revise containment requirements during handling irradiated fuel and core alterations (ML040400343).
TSTF-571, Revision 0, Revise Actions for Inoperable Source Range Neutron Flux Monitor (pages 6 to 30 of the document in ML18221A561). Revises the Required Actions for an inoperable source range neutron flux monitor to prohibit the movement of fuel assemblies, sources, and reactivity control components when a core subcritical neutron flux monitor is inoperable. A provision is included to allow such movement if it is needed to repair the core subcritical neutron flux monitor.
2.0 STATE CONSULTATION
In accordance with the Commissions regulations, the Illinois State officials were notified of the proposed issuance of the amendments on December 19, 2025. The State officials had no comments.
3.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in Title 10 of the Code of Federal Regulations (10 CFR), part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, which was published in the Federal Register on May 14, 2025 (90 FR 20516), and there has been no public comment on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9) and 10 CFR 51.22(c)(10). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
SUBJECT:
BRAIDWOOD STATION, UNITS 1 AND 2; AND BYRON STATION, UNIT NOS. 1 AND 2 - ISSUANCE OF AMENDMENT NOS.245, 245, 243 AND 243 TO ADOPT TECHNICAL SPECIFICATIONS TASK FORCE TRAVELERS TSTF-286, TSTF-471, AND TSTF-571 (EPID L-2025-LLA-0050)
DATED FEBRUARY 4, 2026 DISTRIBUTION:
PUBLIC RidsNrrDorlLpl3 Resource RidsRgn3MailCenter Resource RidsNrrLASLent Resource RidsAcrs_MailCTR Resource RidsNrrPMConstellation Resource RidsNrrPMBraidwood Resource RidsNrrPMByron Resource RidsNrrDssStsb Resource RidsNrrDssSnsb Resource KWest, NRR MSchwieg, NRR JAnderson, NRR Accession No.: ML26020A287
- via memorandum NRR-058 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DSS/STSB/BC*
NAME SWall SLent SMehta DATE 01/20/2026 01/23/2026 12/19/2025 OFFICE NRR/DSS/SNSB/BC NRR/DORL/LPL3/BC (A)
NRR/DORL/LPL3/PM NAME NDifrancesco IBerrios SWall DATE 01/27/2026 02/03/2026 02/04/2026 OFFICIAL RECORD COPY