05000282/LER-2024-001-01, Auxiliary Building Special Ventilation System Inoperable During Movement of Irradiated Fuel Assemblies

Auxiliary Building Special Ventilation System Inoperable During Movement of Irradiated Fuel Assemblies

ML24296B194
Person / Time
Site:	Prairie Island
Issue date:	10/22/2024
From:	Currier B Northern States Power Company, Minnesota, Xcel Energy
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
L-Pl-24-047 LER 2024-001-01
Download: ML24296B194 (1)

LER-2024-001, Auxiliary Building Special Ventilation System Inoperable During Movement of Irradiated Fuel Assemblies

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
2822024001R01 - NRC Website

text

(l Xcel Energy October 22, 2024 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Prairie Island Nuclear Generating Plant, Units 1 and 2 Docket Nos. 50-282 and 50-306 Renewed Facility Operating License Nos. DPR-42 and DPR-60 1717 Wakonade Drive Welch, MN 55089 L-Pl-24-047 10 CFR 50.73 Prairie Island Nuclear Generating Plant Licensee Event Report 2024-001-01 Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy (hereafter "NSPM"), hereby submits Licensee Event Report (LER) 50-282/2024-001-01 per 10 CFR 50.73(a)(2)(i)(B). This report is a planned supplement to LER 2024-001-00 submitted on September 16, 2024 (ADAMS Accession number ML24260A256).

Summary of Commitments T

letter m e

w commitments and no revisions to existing commitments.

BrOer Plant Manager, Prairie Island Nuclear Generating Plant Northern States Power Company - Minnesota Enclosure cc:

Administrator, Region Ill, USNRC Project Manager, Prairie Island, USNRC Resident Inspector, Prairie Island, USNRC State of Minnesota

ENCLOSURE PRAIRIE ISLAND NUCLEAR GENERATING PLANT LICENSEE EVENT REPORT 50-282/2024-001-01 4 pages follow

Abstract

Prairie Island Nuclear Generating Plant, Unit 1

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Auxiliary Building Special Ventilation System Inoperable during movement of irradiated fuel assemblies.

05 02 2024 2024 001 01 10 22 2024 Prairie Island Unit 2

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100

Nathan Fedora 612-342-8971

On May 02, 2024, the Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2 were operating at 100 percent power while performing fuel handling operations. For a 33-minute period between 12:52 and 13:25, radiation monitors 1R-37 and 2R-30 were both out of service while movement of irradiated fuel assemblies was occurring. On July 11, 2024, while completing a review of the design and licensing basis of radiation monitors 1[2]R-37, 1[2]R-30, it was determined that these monitors are required for Auxiliary Building Special Ventilation System (ABSVS) operability during movement of irradiated fuel assemblies per Technical Specification (TS) 3.7.12. Changes to fuel handling procedures have been initiated. TS Bases for the ABSVS were further clarified and communicated to the operating crews. This will ensure compliance with TS going forward when irradiated fuel is being moved.

This event is reportable under 10 CFR 50.73(a)(2)(i)(B) for an Operation or Condition Prohibited by Technical Specifications.Page of

3. LER NUMBER YEAR SEQUENTIAL NUMBER REV NO.

052 050 ASSESSMENT OF SAFETY CONSEQUENCES During this event, there was always a redundant radiation monitor capable of detecting a potential radiological release out of either unit's exhaust stack which would have resulted in a Train A or Train B ABSVS actuation during a postulated FHA depending on which unit's exhaust stack the high radiation was first detected. Actuation of either the Train A or Train B ABSVS results in the elimination of both Unit 1 and Unit 2 ABNV exhaust stacks as potential radiological release sources.

This performs the safety function credited by the ABSVS during an FHA event.

The health and safety of the public and site personnel were not impacted during this event.

CAUSE OF THE EVENT TS Bases were changed to clarify operability requirements of the ABSV system without ensuring the license holders understood the changes to TS 3.7.12 Bases.

Operating procedures were not updated to include steps to evaluate TS 3.7.12 if radiation monitors were inoperable or out of service.

CORRECTIVE ACTIONS TS Bases for the ABSV system were further clarified and communicated to the operating crews.

Changes to fuel handling procedures have been initiated. This will ensure compliance with TS going forward when irradiated fuel is being moved.

PREVIOUS SIMILAR EVENTS There were no previous similar events in the past three years.

ADDITIONAL INFORMATION All times are in Central Daylight Time.

Energy Industry Identification System (EIIS) codes are identified in the text as [XX].

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Prairie Island Nuclear Generating Plant, Unit 1

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