ML25234A213
| ML25234A213 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 09/02/2025 |
| From: | Robert Kuntz Plant Licensing Branch III |
| To: | Rhoades D Constellation Energy Generation |
| Kuntz, R.F. | |
| References | |
| EPID L-2025-LLR-0045 | |
| Download: ML25234A213 (4) | |
Text
September 2, 2025 LASALLE COUNTY STATION, UNIT 1 - AUTHORIZATION AND SAFETY EVALUATION FOR ALTERNATIVE REQUEST NO. I4R-15 (EPID L-2025-LLR-0045)
LICENSEE INFORMATION Recipients Name and Address:
Mr. David P. Rhoades Senior Vice President Constellation Energy Generation, LLC President and Chief Nuclear Officer Constellation Nuclear 4300 Winfield Road Warrenville, IL 60555 Licensee:
Constellation Energy Generation, LLC Plant Name and Unit:
LaSalle County Station (LaSalle), Unit 1 Docket No.:
50-373 APPLICATION INFORMATION Submittal Date: April 17, 2025 Submittal: Agencywide Documents Access and Management System (ADAMS)
Accession No. ML25108A048 Applicable Containment Inservice Inspection Program Interval and Interval Start/End Dates: LaSalle, Unit 1 third containment inservice inspection (CISI) interval, under the fourth inservice inspection (ISI). The interval started on October 1, 2017, and ends on September 30, 2027.
Alternative Provision: The licensee requested an alternative pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(z)(1) that the alternative provides an acceptable level of quality and safety.
CISI Requirement: American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components subsections IWL-2410(a), IWL-2410 (c), IWL-2510, and Table IWL-2500-1 (L-A).
Applicable Code Edition and Addenda: ASME Code,Section XI, 2007 Edition with 2008 Addenda Brief Description of the Proposed Alternative:
The licensees proposed alternative I4R-15, corresponding to the above code requirements, is a one-time extension to the end date of the current 2-year examination window for LaSalle, Unit 1, restricted containment areas from September 15, 2025, to March 15, 2026. This extension is requested to allow the licensee to perform surface examinations in restricted containment areas that have not yet been examined, during the refueling outage (L1R21) in early 2026.
For additional details on the licensees request, please refer to the document located at the ADAMS Accession No. identified above.
STAFF EVALUATION Due to restricted area access of the LaSalle, Unit 1, containment and scheduling errors, the licensee proposed a one-time extension of the 2-year examination period required by ASME Code Section XI, Subsections IWL-2410(a) and IWL-2410(c) for the ASME Section XI, Subsection Table IWL-2500-1 (L-A) and IWL-2510 surface examinations, from September 15, 2025, to March 15, 2026. This extension would allow the required containment surface examinations to be conducted in accordance with ASME Code Section XI, Table IWL-2500-1 (L-A) and Subsection IWL-2510 during L1R21, when access to the affected areas will be available.
To determine whether the proposed alternative provides an acceptable level of quality and safety during the extended period, the NRC staff reviewed how it affects the aging management of the LaSalle, Unit 1, concrete containment.
The NRC staff reviewed the information provided in the alternative request and noted that:
(1) the surface examinations of accessible LaSalle, Unit 1, containment surface areas except certain restricted areas, have been completed or will be completed in accordance with ASME Code Section XI, Table IWL-2500-1 (L-A) and Subsection IWL-2510 prior to the end of the two year examination period on September 15, 2025, as required by ASME Code Section XI, Subsections IWL-2410(a) and IWL-2410 (c);
(2) the areas for which the extension is requested for the LaSalle, Unit 1, containment are limited to those that are physically inaccessible during online operation. No concrete surface degradations are currently being tracked in these areas. The licensee will perform the IWL-2510 examinations for those restricted concrete containment surface areas during L1R21, and the licensees corrective action program will evaluate and disposition any degradations identified during the extended period; (3) during the most recent refueling outage in 2024, inspections of the metallic liner-to-drywell floor interface were completed, and no adverse conditions were identified; and (4) the licensees corrective action program has addressed the scheduling issue to ensure that future IWL-2510 examinations will be scheduled within the required examination windows based on ASME Code Section XI, Subsections IWL-2410(a) and IWL-2410 (c).
Based on the above, the NRC staff finds that the licensee has completed, or will complete, all the surface examinations including certain restricted areas, as required by ASME Section XI, Table IWL-2500-1 (L-A) and Subsection IWL-2510 for the LaSalle, Unit 1, containment within the original and extended periods discussed above, and deferred examinations have no significant impact on the aging management of the LaSalle, Unit 1, concrete containment.
Additionally, the NRC staff finds that the one-time, 6-month extension of the 2-year examination period is necessary for the licensee to complete the remaining surface examinations in restricted areas as required by the ASME Code. Therefore, the NRC staff concludes that the proposed alternative for a one-time, 6-month extension to the 2-year examination period, which allows for the completion of surface examinations on certain restricted containment areas, provides an acceptable level of quality and safety.
Summary Based on the above evaluation, the NRC staff determines that the licensee has demonstrated that the proposed examinations during the extension period meet the applicable requirements of ASME BPV Code,Section XI, Table IWL-2500-1 (L-A) and Subsection IWL-2510. Therefore, the NRC staff finds that that the proposed alternative provides an acceptable level of quality and safety in accordance with 10 CFR 50.55a(z)(1).
The NRC staff authorizes a one-time extension of the 2-year examination period during the third CISI 10-year IWL Interval for the licensee to perform surface examinations of certain restricted containment areas at LaSalle, Unit 1. This extension permits examinations to be conducted from September 15, 2025, to March 15, 2026, in accordance with ASME Section XI, Table IWL-2500-1 (L-A) and Subsection IWL-2510.
CONCLUSION The NRC staff has determined that the proposed alternative in the licensees request referenced above would provide an acceptable level of quality and safety and concludes that the licensee has adequately addressed the regulatory requirements set forth in 10 CFR 50.55a(z)(1).
The NRC staff authorizes the use of proposed alternative I4R-15 for certain restricted containment areas of LaSalle, Unit 1, as a one-time period extension of the 2-year examination period during the third CISI 10-year IWL Interval, as stipulated in the staff evaluation Summary section above.
All other ASME BPV Code,Section XI, requirements for which an alternative was not specifically requested and authorized remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.
Principal Contributor: Aaron Gallman, NRR Date: September 2, 2025 Ilka Berrios, Acting Chief Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation cc: Listserv ILKA BERRIOS Digitally signed by ILKA BERRIOS Date: 2025.09.02 12:30:45 -04'00'
ML25234A213 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DEX/ESEB/BC NRR/DORL/LPL3/BC(A)
NAME RKuntz SLent ITseng (GWang for) IBerrios DATE 8/21/2025 8/26/2025 8/20/2025 9/2/2025