ML25233A245
| ML25233A245 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 08/28/2025 |
| From: | V Sreenivas NRC/NRR/DORL/LPL1 |
| To: | Rhoades D Exelon Generation Co, Exelon Nuclear |
| Sreenivas V, NRR/DORL/LPL1 | |
| References | |
| EPID L-2025-LLA-0087 | |
| Download: ML25233A245 (1) | |
Text
August 28, 2025 Mr. David P. Rhoades Senior Vice President Constellation Energy Generation, LLC President and Chief Nuclear Officer Nuclear Constellation 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
R. E. GINNA NUCLEAR POWER PLANT - AUDIT PLAN IN SUPPORT OF LICENSE AMENDMENT REQUEST TO EXTEND THE COMPLETION TIME FOR SODIUM HYDROXIDE SYSTEM (EPID L-2025-LLA-0087)
Dear Mr. Rhoades:
By letter dated May 20, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25140A128), Constellation Energy Generation, LLC (licensee) submitted a license amendment request for R. E. Ginna Nuclear Power Plant. The proposed change extends the Completion Time for Technical Specification 3.6.6 Containment Spray, Containment Recirculation Fan Cooler, and NaOH Systems, Required Action B Sodium Hydroxide system inoperable. Specifically, the proposed change extends the Required Action B Completion Time (CT) from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days.
The U.S. Nuclear Regulatory Commission (NRC) staff has identified the need for a regulatory audit to examine the licensees non -docketed information with the intent to gain understanding, to verify information, or to identify information that will require a docketing to support the basis of the licensing or regulatory decision.
The NRC staff will conduct the audit virtually via Microsoft Teams using a licensee-established electronic portal available to NRC staff from approximately September 8, 2025, through September 30, 2025, with formal audit meetings to be scheduled during this period, as needed.
The detailed audit plan is enclosed with this letter.
D. Rhoades If you have any questions, please contact me by telephone at 301-415-2597 or by email to V.Sreenivas@nrc.gov.
Sincerely,
/RA/
V. Sreenivas, Project Manager Plant Licensing Branch I Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-244
Enclosure:
Audit Plan cc: Listserv
Enclosure REGULATORY AUDIT PLAN BY THE OFFICE OF NUCLEAR REACTOR REGULATION IN SUPPORT OF LICENSE AMENDMENT REQUEST TO EXTEND THE COMPLETION TIME FOR SODIUM HYDROXIDE SYSTEM CONSTELLATION ENERGY GENERATION, LLC R. E. GINNA NUCLEAR POWER PLANT DOCKET NO. 50-244
1.0 BACKGROUND
By letter dated May 20, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25140A128), Constellation Energy Generation, LLC (licensee) submitted a license amendment request for R. E. Ginna Nuclear Power Plant. The proposed change extends the Completion Time for Technical Specification 3.6.6 Containment Spray, Containment Recirculation Fan Cooler, and NaOH Systems, Required Action B Sodium Hydroxide system inoperable. Specifically, the proposed amendments would modify technical specification (TS) requirements to extend the Required Action B Completion Time from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days. It is stated that the TS change will allow the licensee for maintenance to be performed online and eliminate the potential need for Notice of Enforcement Discretion in the future.
The U.S. Nuclear Regulatory Commission (NRC) staff has initiated its review of the license amendment request (LAR) in accordance with the Office of Nuclear Reactor Regulation (NRR)
Office Instruction (OI) LIC-101, License Amendment Review Procedures (ML19248C539) and has determined that a regulatory audit of the information identified in the Information Requests section below would assist in the timely completion of the review process. The audit will be conducted in accordance with NRR OI LIC-111, Revision 2, Regulatory Audits (ML24309A281). The NRC staff continues to review other aspects of the licensees submittal and may identify the need for additional audit subjects by separate correspondence.
2.0 REGULATORY AUDIT BASES A regulatory audit is a planned license or regulation-related activity that includes the examination and evaluation of the licensees non-docketed information that provides the technical basis for the LAR. An audit is conducted to gain understanding, to verify information, and to identify information that will require docketing to support the basis of a licensing or regulatory decision. An audit will assist the NRC staff in efficiently conducting its review and gaining insights into the licensees processes and procedures. Information that the NRC staff relies upon to make the safety determination must be submitted on the docket.
In accordance with Title 10 of the Code of Federal Regulations (10 CFR) 50.36, Technical specifications, 10 CFR 50.36(b) states in part: The technical specifications will be derived from the analyses and evaluation included in the safety analysis report, and amendments thereto, submitted pursuant to 50.34.
The NRC staff will perform the audit to support its evaluation of whether the licensees request can be approved per 10 CFR 50.90, Application for amendment of license, construction permit, or early site permit.
As provided in Regulatory Guide 1.183, implementation of the alternative source term (AST) by the licensee required re-analyzing several design-basis accidents using new source terms. The licensee performed these tasks by following the requirements of 10 CFR 50.67, Accident source term. An acceptable accident source term is a permissible amount of radioactive material that could be released to the containment from the damaged core following an accident. As a result of improved understanding of the mechanisms of the release of radioactivity, 10 CFR 50.67 permits licensees to voluntarily replace their current Technical Information Document (TID) 14844, Calculation of Distance Factors for Power and Test Reactor Sites, accident source term with the AST. However, this replacement is subject to performing a successful re-evaluation of the major design-basis accidents.
NUREG-1465, Accident Source Terms for Light-Water Nuclear Power Plants, iodine released from the damaged core to the containment after a loss-of-coolant accident is composed of 95 percent cesium iodide, which is a highly ionized salt, soluble in water. Iodine in this form does not present any radiological problems since it remains dissolved in the sump water and does not enter the containment atmosphere. However, in the radiation field existing in the containment, some of this iodine could be transformed from the ionic to the elemental form, which is scarcely soluble in water and can be, therefore, released to the containment atmosphere. Conversion of iodine to the elemental form depends on several parameters, of which pH is very important. Maintaining pH basic in the sump water will ensure that this conversion will be minimized.
NUREG-0800, Section 6.5.2, Containment Spray as a Fission Product Cleanup System, states, in part, that long-term iodine retention may be assumed only when the equilibrium sump solution pH, after mixing and dilution with the primary coolant and ECCS injection, is above 7.
The regulations in 10 CFR 50.46 require an emergency core cooling system (ECCS) to mitigate a design-basis accident. As stated, in part, in 10 CFR 50.46(a), that each pressurized light-water nuclear power reactor... must be provided with an emergency core cooling system (ECCS) that must be designed so that its calculated cooling performance following postulated loss-of-coolant accidents conforms to the criteria set forth in paragraph (b) of this section. The regulations in 10 CFR 50.46(b)(5), Long-term cooling, states After any calculated successful initial operation of the ECCS, the calculated core temperature shall be maintained at an acceptably low value and decay heat shall be removed for the extended period of time required by the long-lived radioactivity remaining in the core.
Regulatory Guide 1.82, Revision 3, Water Sources for Long-Term Recirculation Cooling Following a Loss-of-Coolant Accident, Section 1.1.2, states, in part, that debris that could accumulate on the sump screen should be minimized.
The audit will assist the NRC staff with understanding the licensees proposed request of extending the completion time.
3.0 SCOPE The audit team will view the documentation and calculations that provide technical support for the LARs. The scope of the NRC staffs audit will focus on the following subjects:
Along with appropriate discussion, the audit team will view any documentation and calculations that provide technical support for the LAR to:
Establish an understanding of areas where the NRC staff has identified potential concerns with the LAR to enable the staff to issue clear requests for information and for the licensee to provide quality and timely responses.
Identify questions and requests that may become formal requests for additional information (RAI) per NRR Office Instruction LIC-115, (Revision 1) Processing Requests for Additional Information (ML21141A238).
Gain a better understanding of the bases underlying the LAR and confirm the NRC staffs understanding of the LAR.
In addition, the audit team will request the licensee to discuss these topics with CEGs subject matter experts. The NRC staff will conduct this audit under the guidance provided in NRR Office Instruction LIC-111, Regulatory Audits, Revision 2.
4.0 INFORMATION AND OTHER MATERIAL NECESSARY FOR THE REGULATORY AUDIT The NRC staff will request information and interviews throughout the audit period. The NRC staff will use an audit items list to identify the information to be audited (e.g., methodology, process information, and calculations) and the subjects of requested interviews and meetings.
The NRC staff requests the licensee to have the information referenced in the attachment of this audit plan available and accessible for the NRC staffs review via a web-based electronic portal within two weeks of the date of this audit plan. The NRC staff requests that any supplemental information requested be available and accessible for the NRC staffs review within one week of the date of the NRCs notification to the licensee of the new requests. The NRC staff requests the licensee to notify the review team when an audit item is added to its electronic portal by sending an email to the NRC licensing project manager (PM).
The NRC staff acknowledge and will observe appropriate handling and protection of Proprietary information made available for the audit. Any information accessed through the licensees portal will not be held or retained in any way by NRC staff.
5.0 AUDIT TEAM The following are the NRC audit team members and their respective areas of focus during the audit:
NRR Staff Email Division/Branch V. Sreenivas, PM V.Sreenivas@nrc.gov DORL/LPL11 Mathew Hamm Matthew.Hamm@nrc.gov DSS/STSB2 John Parillo John.Parillo@nrc.gov DRA/ARCB3 Mathew Yoder Matthew.Yoder@nrc.gov DNRL/NCSG4 Paul Klein Paul.Klein@nrc.gov DNRL/NCSG4 Reena Boruk Reena.Boruk@nrc.gov DNRL/NCSG4 1 Division of Operating Reactor Licensing, Plant Licensing 1 2 Division of Safety Systems, Technical Specifications Branch 3 Division of Risk Assessment, Radiation Protection and Consequence 4 Division of New and Renewed Licenses, Corrosion and Steam Generator Branch 6.0 LOGISTICS The audit will be conducted using a secure, online electronic portal established by the licensee to present supporting documentation and calculations and by interviews with the licensees subject matter experts virtually. The audit will begin approximately within two weeks of the date of this audit plan.
A desktop audit will take place between approximately September 2, 2025, and September 30, 2025. The NRC licensing PM will inform the licensee of the entrance and exit meeting dates once they are established. The NRC PM will coordinate with the licensee to set dates and times to discuss information needs and questions arising from the NRCs review of the audited items.
The NRC staff may change and/or add audit dates and times when deemed necessary. The audit meeting agenda and questions will be sent in advance of the audit meeting.
The following conditions associated with the online web-based electronic portal should be maintained while the NRC staff and contractors on the audit team have access to the online portal:
The online electronic portal will be password-protected, and separate passwords will be assigned to each member of the audit team.
The online web-based electronic portal will be sufficiently secure to prevent the NRC staff and contractors from printing, saving, downloading, or collecting any information from the web portal.
Conditions of use of the online electronic portal will be displayed on the login screen and will require acknowledgment by each user.
The NRC PM will provide the licensee with the names and contact information of the NRC staff and contractors who are added to the audit team. The licensee will provide username and password information directly to the NRC staff and contractors on the audit team listed above.
All other communications should be coordinated with the NRC PM. The NRC PM will inform the licensee via routine communications when the NRC staff no longer need access to the electronic portal.
No data accessed by the audit team members will be retained by the NRC following the conclusion of the audit.
8.0 DELIVERABLES The NRC staff will develop any RAIs, as needed, in accordance with NRR LIC-115 and issue such RAIs separate from audit-related correspondence. The NRC staff will issue an audit summary report within approximately 90 days after the end of the audit and prior to completing its safety evaluation of the LAR.
Attachment INITIAL AUDIT MATERIAL REQUEST ITEM AUDIT REQUEST 1
Discuss the impact to offsite dose as well as control room habitability of not injecting NaOH during an accident.
2 Discuss the impact to equipment qualification for submerged equipment during an accident if NaOH is not injected.
3 Describe the relative change in chemical precipitates calculated to form in the existing analysis which includes NaOH injection vs unbuffered case and the impact on emergency core cooling system.
4 Describe any compensatory measure that could be taken to justify continued operation during loss of function situation.
5 Provide Operating Experience on number of times NaOH caused entry into TS 3.6.6 Condition C.
6 Provide estimated time needed to restore NaOH system to Operable Status.
7 Provide an evaluation of failure mechanisms of the NaOH system and discuss possible separate conditions and appropriate Completion Times for each type of failure.
8 Discuss the potential for re-evolution of I2 due to an unbuffered containment sump.
ML25233A245 NRR-106 OFFICE NRR/DORL/LPL1/PM NRR/DORL/LPL1/LA NRR/DSS/STSB/BC NRR/DNRL/NCSG/BC NAME VSreenivas KEntz SMehta SBloom DATE 08/14/2025 08/25/2025 08/27/2025 08/26/2025 OFFICE NRR/DSS/ARCB/BC NRR/DORL/LPL1/BC NRR/DORL/LPL1/PM NAME KHsueh HGonzález VSreenivas DATE 08/27/2025 08/27/2025 08/28/2025