ML25345A246
| ML25345A246 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 12/11/2025 |
| From: | Knowles J Constellation Energy Generation |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| Download: ML25345A246 (0) | |
Text
200 Energy Way Kennett Square, PA 19348 www.constellation.com 10 CFR 50.12 December 11, 2025 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 R.E. Ginna Nuclear Power Plant Renewed Facility Operating License No. DPR-18 NRC Docket No. 50-244
Subject:
10 CFR 50.12 Exemption Request for Alternate Material Properties Bases In accordance with 10 CFR 50.12, "Specific exemptions," paragraph (a)(1) and (a)(2)(v),
Constellation Energy Generation, LLC (CEG), is requesting NRC approval of an exemption from certain requirements of 10 CFR 50, Appendix G, "Fracture Toughness Requirements," and 10 CFR 50.61, "Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events." The requested exemption would allow use of an alternate method, the Master Curve Methodology, as described in AREVA NP Topical Report BAW-2308, Revisions 1-A and 2-A, "Initial RTNDT of Linde 80 Weld Materials," for determining the initial, unirradiated material reference temperatures of the Linde 80 weld materials present in the reactor pressure vessel (RPV) beltline and extended beltline region for R.E. Ginna Nuclear Power Plant (Ginna).
The requested exemption would allow the site to submit a License Amendment Request to adopt BAW-2308, Revisions 1-A and 2-A as an approved methodology for TS 5.6.6, "Reactor Coolant System (RCS) Pressure and Temperature Limits Report (PTLR)," for determining RCS pressure-temperature (P-T) limits for the subsequent license renewal.
Ginna will not be implementing these changes until the second 20 year license renewal operating period.
In addition, in accordance with 10 CFR 50.12 and 10 CFR 50.60(b), CEG requests an exemption to portions of the following regulations:
- 1. 10 CFR 50.61, "Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events," which sets forth fracture toughness requirements for protection against pressurized thermal shock (PTS); and
- 2. 10 CFR 50, Appendix G, "Fracture Toughness Requirements," which sets forth fracture toughness requirements for ferritic materials of pressure-retaining components of the reactor coolant pressure boundary of light water nuclear power reactors to provide adequate margins of safety during any condition of normal operation, including anticipated operational occurrences and system
- - Constellation
U.S. Nuclear Regulatory Commission 10 CFR 50.12 Exemption Request for Alternate Material Properties Bases December 11, 2025 Page 2 hydrostatic tests, to which the pressure boundary may be subjected over its service lifetime.
The attachment provides the Exemption Request and details of the 10 CFR 50.12 request.
The proposed change has been evaluated in accordance with 10 CFR 50.91(a)(1) using criteria in 10 CFR 50.92(c) and it has been determined that this change involves no significant hazards considerations.
CEG requests approval of the proposed Exemption Request within one year of this submittal date; i.e., by December 11, 2026. The new methodology will not be incorporated into the PTLR and TS until the second 20 year license extension begins in 2029.
There are no new regulatory commitments contained in this submittal.
Should you have any questions concerning this submittal, please contact Abul Hasanat at 267-533-5733 or via email at Abul.Hasanat@Constellation.com.
I declare under penalty of perjury that the foregoing is true and correct. Executed on December 11, 2025.
Respectfully, Justin W. Knowles Senior Manager - Licensing Constellation Energy Generation, LLC
Attachment:
Exemption Request cc: USNRC Regional Administrator, Region I w/attachment USNRC Senior Resident Inspector, Ginna w/attachment USNRC Project Manager, Ginna w/attachment
-05'00' y
ATTACHMENT EXEMPTION REQUEST R.E. Ginna Nuclear Power Plant Renewed Facility Operating License No. DPR-18 Docket No. 50-244
ATTACHMENT Exemption Request Page 1 of 7 1.0 SPECIFIC EXEMPTION REQUEST In accordance with 10 CFR 50.12, "Specific exemptions," paragraph (a)(1) and (a)(2)(v),
Constellation Energy Generation, LLC (CEG) is requesting NRC approval of an exemption from certain requirements of 10 CFR 50, Appendix G, "Fracture Toughness Requirements," and 10 CFR 50.61, "Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events." The requested exemption would allow use of an alternate method, the Master Curve Methodology, as described in AREVA NP Topical Report BAW-2308, Revisions 1-A and 2-A, "Initial RTNDT of Linde 80 Weld Materials," for determining the initial, unirradiated material reference temperatures of the Linde 80 weld materials present in the reactor pressure vessel (RPV) in both the beltline and extended beltline region for R.E. Ginna Nuclear Power Plant (Ginna).
2.0 BASIS FOR EXEMPTION REQUEST BACKGROUND 10 CFR 50.61 (a)(5) and 10 CFR 50, Appendix G(ll)(D)(i), require that the pre-service or unirradiated condition reference temperature, nil-ductility transition, (RTNDT) be evaluated according to the procedures in the American Society for Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Section Ill, Paragraph NB-2331, which requires Charpy V-notch impact tests and drop weight tests. In addition,10 CFR 50.61 permits other methods for use in determining the initial material properties provided such methods are approved by the Director, Office of Nuclear Reactor Regulation.
AREVA NP Topical Report BAW-2308, Revisions 1-A and 2-A, provides NRC-approved alternate initial RTNDT DQGDVVRFLDWHGXQFHUWDLQW\\WHUP I) values of the Linde 80 weld materials present in the beltline and extended beltline region of the RPV at Ginna.
BAW-2308, Revision 2-A (Reference 2), is a supplement to Revision 1-A (Reference 1),
and incorporated additional test data and a reevaluation of the reference temperature T0, determination, as requested by the NRC in the Safety Evaluation (SE) for Revision 1-A of BAW-2308. As stated in the NRC SE for Revision 2-A of the topical report dated March 24, 2008, the Conditions and Limitation, Items (1) through (4), contained in the SE for Revision 1-A of the topical report must be satisfied in order for licensees to reference the topical report in specific licensing applications.
Conditions and Limitations Item (4) contained in the SE for Revision 1-A of BAW-2308 states:
Any licensee who wants to utilize the methodology of TR BAW-2308, Revision 1 as outlined in items (1) through (3) above, must request an exemption, per 10 CFR 50.12, from the requirements of Appendix G to 10 CFR Part 50 and 10 CFR 50.61 to do so. As part of a licensee's exemption request, the NRC staff expects that the licensee will also submit information which demonstrates what values the
ATTACHMENT Exemption Request 2 of 7 OLFHQVHHSURSRVHVWRXVHIRU57NDT and the margin term for each Linde 80 weld in its RPV through the end of its facility's current operating license.
In the above quotation, Conditions and Limitations Item (1) pertains to NRC-accepted, values of initial (unirradiated) reference temperature, IRTTO, and the corresponding XQFHUWDLQW\\WHUPI, for Linde 80 weld materials based on the Master Curve methodology using direct testing of fracture toughness in accordance with American Society for Testing and Materials (ASTM) Standard Test Method E1921 (1997 and 2002 Editions).
Conditions and Limitations Item (2) requires that a minimum chemistry factor of 167.0°F be applied when the methodology of Regulatory Guide (RG) 1.99, Revision 2, "Radiation Embrittlement of Reactor Vessel Materials," and 10 CFR 50.61 is used to assess the shift in nil-ductility transition temperature due to irradiation.
&RQGLWLRQVDQG/LPLWDWLRQV,WHP UHTXLUHVWKDWDYDOXHRI = 28.0°F be used to determine the margin term, as defined in BAW-2308, Revision 1-A, and RG 1.99, Revision 2.
Table 9 of BAW-2308 Revision 2-A contains the values proposed to be used for IRTTO and the initial margin term for Linde 80 heat numbers present in the Ginna Station RPV beltline and extended beltline (Reference 2). Ginna will not be implementing these changes until the second 20 year license renewal operating period. The subsequent OLFHQVHUHQHZDO 6/5 DSSOLFDWLRQZLOOLQFOXGH57NDT and the margin term for each Linde 80 weld value which support above conditions and limitations.
Constellation Energy desires to use the BAW-2308 initial RTNDT values in the new analyses that will be submitted with the SLR application. Therefore, exemption from certain requirements of 10 CFR 50.61 and 10 CFR 50, Appendix G is required.
PROPOSED EXEMPTION The exemption requested by CEG addresses portions of the following regulations:
(1) 10 CFR 50, Appendix G, "Fracture Toughness Requirements," which sets forth fracture toughness requirements for ferritic materials of pressure-retaining components of the reactor coolant pressure boundary of light water nuclear power reactors to provide adequate margins of safety during any condition of normal operation, including anticipated operational occurrences and system hydrostatic tests, to which the pressurized boundary may be subjected over its service lifetime; and (2) 10 CFR 50.61, "Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events," which sets forth fracture toughness requirements for protection against pressurized thermal shock (PTS).
ATTACHMENT Exemption Request 3 of 7 The exemption from Appendix G to 10 CFR 50 is to replace the required use of the existing Charpy V-notch and drop-weight-based methodology with the use of an alternate methodology that incorporates the use of fracture toughness test data for evaluating the integrity of the Linde 80 weld materials present in Ginna RPV beltline and extended beltline regions. The alternate methodology employs direct fracture toughness testing per the Master Curve methodology based on use of ASTM Standard Test Method E1921 (1997 and 2002 editions), and ASME Code Case N-629. The exemption is required since 10 CFR 50, Appendix G, requires that for the preservice or unirradiated condition, RTNDT be evaluated by Charpy V-notch impact tests and drop weight tests according to the procedures in the ASME Code, Section Ill, Paragraph NB-2331.
The exemption from 10 CFR 50.61 is to use an alternate methodology to allow the use of direct fracture toughness test data for evaluating the integrity of the Linde 80 weld materials present in the Ginna RPV beltline and extended beltline regions, based on the use of the ASTM Standard Test Method E1921 (1997 and 2002 editions), and ASME Code Case N-629. The exemption is required because the methodology for evaluating RPV material fracture toughness in 10 CFR 50.61 requires that the pre-service or unirradiated condition be evaluated using by Charpy V-notch impact tests and drop weight tests according to the procedures in the ASME Code, Section Ill, Paragraph NB-2331.
Additionally, the NRC SE for Topical Report BAW-2308, Revision 1-A, concludes that an exemption is required to address issues related to 10 CFR 50.61 as the methodology presented in Topical Report BAW-2308, Revision 1-A, as modified and approved by the NRC staff, represents a significant change to the methodology specified in 10 CFR 50.61 for determining the Pressurized Thermal Shock (PTS) reference temperature (RT PTS) value for Linde 80 weld material. The changes in the methodology described in BAW-2308, Revisions 1-A and 2-A, with respect to the methodology per 10 CFR 50.61, include the requirements for use of a minimum chemistry factor of 167°F and a value of
= 28.0°F for Linde 80 weld materials.
10 CFR 50.12 states that the Commission may grant an exemption from requirements contained in 10 CFR 50 provided that: 1) the exemption is authorized by law; 2) the exemption will not result in an undue risk to public health and safety; 3) the exemption is consistent with the common defense and security; and 4) special circumstances, as defined in 10 CFR 50.12(a)(2) are present. The requested exemption to allow the use of Topical Report BAW-2308, Revisions 1-A and 2-A (Revision 2-A is a supplement to Revision 1-A), as the basis for the Linde 80 weld material initial properties at Ginna satisfy these requirements, as described below.
- 1. The requested exemption is authorized by law.
ATTACHMENT Exemption Request 4 of 7 No law exists which precludes the activities covered by this exemption request. 10 CFR 50.60(b) allows the use of alternatives to 10 CFR 50, Appendix G, when an exemption is granted by the Commission under 10 CFR 50.12.
In addition, 10 CFR 50.61 permits other methods for use in determining the initial material properties provided such methods are approved by the Director, Office of Nuclear Reactor Regulation.
- 2. The requested exemption does not present an undue risk to the public health and safety.
The proposed material initial properties basis described in Topical Report BAW-2308, Revisions 1-A and 2-A, represent an NRC-approved methodology for establishing weld wire specific and generic IRTTO values for Linde 80 welds. Topical Report BAW-2308, Revisions 1-A and 2-A, includes appropriate conservatisms to ensure that use of the proposed initial material properties basis does not increase the probability of occurrence or the consequences of an accident at Ginna and will not create the possibility for a new or different type of accident that could pose a risk to public health and safety.
The use of this proposed approach ensures that the intent of the requirements specified in 10 CFR 50, Appendix G, and 10 CFR 50.61, are satisfied.
The requested exemption is consistent with the NRC requirements specified in the SE for the approved Topical Report BAW-2308, Revisions 1-A and 2-A; consequently, the exemption does not present an undue risk to the public health and safety.
- 3. The requested exemption will not endanger the common defense and security.
The requested exemption is specifically concerned with RPV material properties and is consistent with NRC requirements specified in the SE (References 1 and 2) for the approved Topical Report BAW-2308, Revisions 1-A and 2-A. Consequently, the requested exemption will not endanger the common defense and security.
- 4. Special circumstances are present which necessitate the request for an exemption to the regulations of 10 CFR 50, Appendix G, and 10 CFR 50.61.
In accordance with 10 CFR 50.12(a)(2), the NRC will not consider granting an exemption to the regulations unless special circumstances are present. The requested exemption meets the special circumstances of 10 CFR 50.12(a)(2)(ii),
since application of the methodology in Topical Report BAW-2308, Revisions 1-A and 2-A, in this particular circumstance serves the underlying purpose of the regulations.
ATTACHMENT Exemption Request 5 of 7 The underlying purpose of 10 CFR 50, Appendix G, and 10 CFR 50.61, is to protect the integrity of the reactor coolant pressure boundary by ensuring that each reactor vessel material has adequate fracture toughness. Application of ASME Code, Section Ill, Paragraph NB-2331, in the determination of initial material properties was conservatively developed based on the level of knowledge existing in the early 1970's concerning RPV materials and the estimated effects of operation.
Since the early 1970's, the level of knowledge concerning these topics has greatly expanded. This increased knowledge level permits relaxation of the ASME Code, Section Ill, Paragraph NB-2331 requirements, via application of Topical Report BAW-2308, Revision 2-A, while maintaining the underlying purpose of the ASME Code and NRC regulations to ensure an acceptable margin of safety is maintained.
COMPLIANCE WITH "CONDITIONS AND LIMITATIONS" OF TOPICAL REPORT BAW-2308 Ginna will follow the Conditions and Limitations.
Therefore, the intent of 10 CFR 50.61 and 10 CFR 50, Appendix G will continue to be satisfied for the proposed change in reactor vessel material initial properties basis, thus justifying the exemption request. Issuance of an exemption for the criteria of these regulations to permit the use of Topical Report BAW-2308, Revisions 1-A and 2-A for Ginna will not compromise the safe operation of the reactor and will ensure that RPV integrity is maintained.
PRECEDENT As further support for this requested exemption, CEG notes that relevant precedent exists for granting an exemption from certain requirements of 10 CFR 50.61, "Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events, and 10 CFR 50, Appendix G, "Fracture Toughness Requirements." The NRC has approved similar exemption requests for Braidwood Nuclear Station, Byron Nuclear Station, Oconee Nuclear Station, Three Mile Island Nuclear Station and Point Beach Nuclear Plant.
The exemption requests and NRC approvals are listed below.
- 1. NRC Letter to Exelon Generation Company, LLC, dated August 31, 2020 Braidwood 1 & 2 and Byron 1 & 2 Exemption from the Requirements of 10 CFR Part 50.61 and 10 CFR Part 50, Appendix G (ML20022A330)
- 2. NRC letter to Duke Energy Carolinas, LLC, dated April 26, 2012, "Oconee Nuclear Station, Units 1, 2, and 3, Exemption from the Requirements of 10 CFR Part 50.61 and 10 CFR Part 50, Appendix G (TAC NOS. ME7000, ME7001, ME7002, ME7003, ME7004, AND ME7005)," (ML120580196)
ATTACHMENT Exemption Request 6 of 7
- 3. NRC letter to Exelon Generation Company, LLC, dated December 13, 2013, "Three Mile Island Nuclear Station, Unit 1 - Exemption from Certain Requirements of 10 CFR Part 50, Appendix G and 1 O CFR 50.61, for Initial RTNDT Values for Linde 80 Welds (TAC NO. MF0425)." (ML13324A086)
- 4. NRC letter to NextEra Energy Point Beach, LLC, dated June 30, 2014, "Point Beach Nuclear Plant (Point Beach), Units 1 and 2 - Exemption from the Requirements of 10 CFR Section 50.61 and Appendix G to 10 CFR Par 50 (TAC NOS. MF0534 and MF0535)." (ML14126A612)
Ill. ENVIRONMENTAL ASSESSMENT CEG has determined that the requested exemption meets the categorical exclusion provision in 10 CFR 51.22(c)(9), as an amendment to Ginnas license under 10 CFR 50 requires the issuance of an exemption request, with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed amendments do not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.
Therefore, in accordance with 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed exemption.
IV. CONCLUSION This exemption request is associated with certain requirements of 10 CFR 50, Appendix G, and 10 CFR 50.61. This required exemption would allow use of an alternate method, the Master Curve Methodology, as described in AREVA NP Tropical Report BAW-2308, Revisions 1-A and 2-A, for determining the initial, unirradiated material reference temperatures of the Linde 80 weld materials present in the reactor pressure vessel beltline and extended beltline region of Ginna station. The Conditions and Limitations on the use of the topical report will be satisfied.
As demonstrated above, we consider that this exemption request is in accordance with the criteria of 10 CFR 50.12. Specifically, the requested exemption is authorized by law, will not present an undue risk to the public health and safety, and is consistent with the common defense and security. Also, special circumstances are present as previously described.
In accordance with 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed exemption.
ATTACHMENT Exemption Request 7 of 7 V. REFERENCES
- 1) NRC letter to AREVA NP, dated August 4, 2005, Final Safety Evaluation for Topical Report BAW-2308, Revision 1, "Initial RTNDT of Linde 80 Weld Materials," (TAC No.
MB6636). (ML052070408)
- 2) NRC letter to Westinghouse Electric Company, dated March 24, 2008, Final Safety Evaluation for Pressurized Water Reactor Owners Group (PWROG) Topical Report (TR) BAW-2308, Revision 2, "Initial RTNDT of Linde 80 Weld Materials," (TAC No.
MD4241). (ML080770349)