PNP 2021-017, Schedule Change to Open Phase Condition Detection Implementation
| ML21091A062 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 04/01/2021 |
| From: | Dotson B Entergy Nuclear Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| PNP 2021-017 | |
| Download: ML21091A062 (3) | |
Text
~ Entergx PNP 2021-017 April 1, 2021 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Entergy Nuclear Operations, Inc.
Palisades Nuclear Plant 27780 Blue Star Memorial Highway Covert, Ml 49043-9530 Tel 269-764-2000 Barbara E. Dotson Manager, Regulatory Assurance (Acting) 10 CFR 50.4
Subject:
Schedule Change to Open Phase Condition Detection Implementation Palisades Nuclear Plant NRC Docket No. 50-255 Renewed Facility Operating License No. DPR-20 Entergy Nuclear Operations, Inc. (Entergy) is revising the implementation schedule for open phase condition for Palisades Nuclear Plant (PNP). In 2014, Entergy committed to the generic schedule for the PNP as provided in Nuclear Energy Institute (NEI) voluntary industry initiative on Open Phase Condition (References 1 and 2). Subsequently, in Reference 3, NEI revised the voluntary industry initiative generic schedule for Open Phase. Entergy withdrew its membership from NEI in February 2018, as discussed in Reference 4, but the withdrawal did not impact prior commitments to NEI documents or commitments made by NEI on behalf of Entergy. NEI revised the implementation schedule again in Reference 5. In Reference 6, Entergy committed for the PNP to adhere to that revised NEI guidance for installation of Open Phase Detection (OPD) on its remaining Safeguards Transformer 1-1.
Subsequently, NEI issued Reference 7, which allowed risk assessment to guide open phase condition actions. Based on this revised guidance, the decision was made to extend the installation of Safeguards Transformer 1-1 OPD at PNP given the following considerations:
Added risk associated with performing maintenance activities on safety significant components during implementation and testing of the modification, Consideration of the normal plant configuration (Safeguards Transformer 1-1 is normally loaded which may be advantageous to allowing Operators to identify and respond to an Open Phase Condition),
Consideration of the station risk after installation of open phase detection on Safeguards Transformer 1-1 as screened under the Entergy Nuclear Risk Management Process, and Consideration of the contribution to core damage risk (measured in core damage frequency, CDF) of an open phase condition consistent with the guidance contained in Reference 8, as well as the NRC document "Preliminary Risk Estimate on the Impact of Open Phase Condition."
It was concluded that extending the installation of the PNP Safeguards Transformer 1-1 OPD system is acceptable from a plant reliability and core damage risk perspective.
PNP 2021-017 Page 2 of3 This letter provides notification to the NRC that Entergy is extending the installation of the remaining OPD for the PNP Safeguards Transformer 1-1 until December 31, 2022. Until that time, Entergy will continue to perform the interim corrective actions specified in Reference 2.
If you have any questions or require additional information, please contact Jim Miksa, Sr. Staff Engineer, at 269-764-2945.
This submittal contains no new regulatory commitments.
Respectfully, BED/gpn
References:
- 1) Nuclear Energy Institute letter to the NRC, "Industry Initiative on Open Phase Condition,n (Accession No. ML13333A147), dated October 9, 2013
- 2) Entergy Letter to NRC, "Response to Request for Additional Information
- NRC Bulletin 2012-01,8 (Accession No. ML14034A169), dated January 30,2014
- 3) Nuclear Energy Institute letter to the NRC, "Industry Initiative on Open Phase Condition, Revision 1, * (Accession No. ML15075A455), dated March 16, 2015
- 4) Entergy Letter to NRC, "Nuclear Energy Institute Commitments,"
(Accession No. ML18068A087), dated March 9, 2018
- 5) Nuclear Energy Institute letter to the NRC, "Industry Initiative on Open Phase Condition, Revision 2,° (Accession No. ML18268A114), dated September 20, 2018
- 6) Entergy Letter to NRC, "Schedule Change to Open Phase Condition Detection Implementation," (Accession No. ML18354A823), dated December 20, 2018
- 7) Nuclear Energy Institute letter to the NRC, *industry Initiative on Open Phase Condition, Revision 3,8 (Accession No. ML19163A176), dated June 6, 2019
PNP 2021-017 Page 3 of 3
- 8) NEI 19-02, "Guidance for Assessing Open Phase Condition Implementation Using Risk Insights," (Accession No. ML19172A086),
dated June 20, 2019 cc:
NRC Region Ill Regional Administrator NRC Project Manager - Palisades Nuclear Plant NRC Senior Resident Inspector - Palisades Nuclear Plant