ML25058A150
| ML25058A150 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 03/04/2025 |
| From: | Scott Wall Plant Licensing Branch III |
| To: | Ferneau K Indiana Michigan Power Co |
| Wall S | |
| References | |
| EPID L-2024-LRO-0050 | |
| Download: ML25058A150 (3) | |
Text
March 4, 2025 Kelly J. Ferneau Executive Vice President and Chief Nuclear Officer Indiana Michigan Power Company Nuclear Generation Group One Cook Place Bridgman, MI 49106
SUBJECT:
DONALD C. COOK NUCLEAR PLANT, UNIT 2 - REVIEW OF THE SPRING 2024 STEAM GENERATOR TUBE INSPECTIONS REPORT (EPID L-2024-LRO-0050)
Dear Kelly J. Ferneau:
By letter dated October 21, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24295A135), Indiana Michigan Power Company (the licensee) submitted information summarizing the results of the spring 2024 steam generator (SG) inspections for the Donald C. Cook Nuclear Plant (CNP), Unit 2. This report was submitted in accordance with Technical Specification (TS) 5.6.7, Steam Generator Tube Inspection Report.
The U.S. Nuclear Regulatory Commission (NRC) staff has completed its review of the 2024 SG tube inspection for CNP, Unit 2. Based on this review, the NRC staff concludes that the information required by TS 5.6.7 has been provided and no additional follow-up action is required at this time. A summary of the NRC staff's review is enclosed.
Please feel free to contact me at (301) 415-2855 if you have any questions or concerns.
Sincerely,
/RA/
Scott P. Wall, Senior Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-316
Enclosure:
Review of the Spring 2024 Steam Generator Tube Inspection Report cc: Listserv
Enclosure REVIEW OF THE SPRING 2024 STEAM GENERATOR TUBE INSPECTION REPORT DONALD C. COOK NUCLEAR PLANT, UNIT 2 DOCKET NO. 50-316 By letter dated October 21, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24295A135), Indiana Michigan Power Company (the licensee) submitted information summarizing the results of the spring 2024 steam generator (SG) inspections that were performed during refueling outage 28 (U2C28) for the Donald C. Cook Nuclear Plant (CNP), Unit 2. This report was submitted in accordance with Technical Specification (TS) 5.6.7, Steam Generator Tube Inspection Report.
CNP, Unit 2, has four Westinghouse Model 54F recirculating SGs. Each SG has 3,592 thermally treated Alloy 690 tubes that have a nominal outside diameter of 0.875 inches, and a nominal wall thickness of 0.050 inches. The tubes are supported by broached stainless steel quatrefoil tube supports. The tubes were hydraulically expanded at each end for the full depth of the tubesheet.
The licensee provided the scope, extent, methods, and results, of their SG tube inspections in the document referenced above. In addition, the licensee described corrective actions such as tube plugging taken in response to the inspection findings.
Based on the review of the information provided, the U.S. Nuclear Regulatory Commission (NRC) staff has the following observations and comments:
The SG tubes have limited tube degradation relative to the approximately 26.8 effective full power years of operating experience. Most tube degradation results from tube wear at support structures, primarily at tube support plate intersections. Only three wear indications had measured depths greater than 20 percent through-wall (TW), and the maximum wear detected during the inspections in any SG was 22 percent TW.
A total of 19 tubes in all SGs are plugged. No SG tubes were plugged during U2C28.
Based on a review of the information provided, the NRC staff concludes that the licensee provided the information required by CNP, Unit 2, TS 5.6.7. In addition, the staff concludes that there are no technical issues that warrant follow-up action at this time since the inspections appear to be consistent with the objective of detecting potential tube degradation and the inspection results appear to be consistent with industry operating experience at similarly designed and operated units.
- via memo OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DNRL/NCSG/BC*
NAME SWall SRohrer SBloom DATE 02/27/2025 03/03/2025 02/26/2025 OFFICE NRR/DORL/LPL3/BC(A)
NRR/DORL/LPL3/PM NAME IBerrios SWall DATE 03/04/2025 03/04/2025