05000263/LER-2018-001, Cancellation of LER 2018-001-00 for Monticello Re Non-Fully Closed Check Valves Resulted in a Potential Pathway Outside of Secondary Containment and Follow-up to Interim Part 21 Report of a Deviation or Failure to Comply
| ML19038A258 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 02/07/2019 |
| From: | Church C Xcel Energy |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-MT-19-012 LER 2018-001 | |
| Download: ML19038A258 (2) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(v), Loss of Safety Function |
| 2632018001R00 - NRC Website | |
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Xcel Energy*
RESPONS I BLE BY NAT U RE.,
February 07, 2019 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Monticello Nuclear Generating Plant Docket No. 50-263 Renewed Facility Operating License No. DPR-22 2807 West County Road 75 Monticello, MN 55362 L-MT-19-012 10 CFR 50.73 10 CFR 21 Notice of Cancellation of LER 2018-001-00, Non-Fully Closed Check Valves Resulted in a Potential Pathway Outside of Secondary Containment and Follow-up to Interim Report of a Deviation or Failure to Comply
References:
- 1) Letter from Monticello Nuclear Generating Plant to NRC "Licensee Event Report 2018-001-00, "Non-Fully Closed Check Valves Resulted in a Potential Pathway Outside of Secondary Containment," dated November 9, 2018.
On November 9, 2018, Northern States Power Company, a Minnesota Corporation (NSPM),
doing business as Xcel Energy, submitted Monticello Nuclear Generating Plant (MNGP)
Licensee Event Report (LER) 2018-001-00 (letter L-MT-18-068). The LER was submitted pursuant to 10 CFR 50.73(a)(2)(ii)(B), as an unanalyzed condition, and pursuant to 10 CFR 50.73(a)(2)(v)(C)&(D), as an event or condition that could have prevented fulfillment of a safety function. This letter is being submitted to cancel (formally withdraw) LER 2018-001-00, consistent with the guidance of NU REG 1022, Revision 3, Sections 2.8 and 5.1.2. This cancellation eliminates the need to supplement the LER.
The LER originally reported that a failure of the core spray keep-fill line check valves to completely close allowed a potential pathway for leakage to the outside of secondary containment which could have exceeded the Technical Specification (TS) dose limit for personnel within the control room envelope following a design basis accident. Consequently both trains of the Control Room Emergency Filtration (CREF) system were declared inoperable resulting in loss of safety function.
NSPM has completed detailed analysis for the leakage and determined that the dose to the control room operators would not have exceeded the TS limit and that the control room would have remained habitable. Therefore, the CREF remained operable and the control room envelope was
Document Control Desk Page 2 capable of shielding the operators from the potential elevated dose rates. There was no loss of safety function, therefore an LER is not required.
This letter also provides a follow-up to the interim 10 CFR 21 report reported in LER 2018-001-
- 00. With no loss of safety function the manufacturing deviation did not result in a substantial safety hazard and therefore this condition is not reportable under 10 CFR 21.
Summary of Commitments This letter makes no new commitments and no revisions to existing commitments.
Christopher R. Church Site Vice President, Monticello Nuclear Generating Plant Northern States Power Company - Minnesota cc:
Administrator, Region 111, USNRC Project Manager, Monticello, USNRC Resident Inspector, Monticello, USNRC Minnesota Department of Commerce