NMP2L2823, Supplemental Information for License Amendment Request Revise Surveillance Requirements to Reduce Excessive Fast Starting of Emergency Diesel Generators

Supplemental Information for License Amendment Request Revise Surveillance Requirements to Reduce Excessive Fast Starting of Emergency Diesel Generators

ML22301A152
Person / Time
Site:	Nine Mile Point
Issue date:	10/28/2022
From:	David Gudger Constellation Energy Generation
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
NMP2L2823
Download: ML22301A152 (1)

Text

200 Exelon Way Kennett Square, PA 19348 www.constellation.com 10 CFR 50.90 NMP2L2823 October 28, 2022 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Nine Mile Point Nuclear Station, Unit 2 Renewed Facility Operating License No. NPF-69 NRC Docket No. 50-410

Subject:

Supplemental Information for License Amendment Request - Revise Surveillance Requirements to Reduce Excessive Fast Starting of Emergency Diesel Generators

Reference:

Letter from D. Gudger (Constellation Energy Generation, LLC) to U.S. Nuclear Regulatory Commission, License Amendment Request - Revise Surveillance Requirements to Reduce Excessive Fast Starting of Emergency Diesel Generators, dated May 24, 2022. (ML22144A018)

By letter dated May 24, 2022 (Reference), Constellation Energy Generation, LLC (CEG) requested a change to Nine Mile Point Nuclear Station, Unit 2 (NMP2) Technical Specifications (TS). The proposed change would revise SR 3.8.1.2 to identify the "Start Test" requirements for the EDGs. In addition, a new SR (SR 3.8.1.19) would be created to identify the "Fast-Start" testing requirements for the EDGs.

This Supplemental Information provides clarification and addresses inconsistencies with the written description of proposed changes in Section 2.0 of the referenced document to align with the proposed changes illustrated in the marked-up TS pages in Attachment 2 of the referenced document. This Supplemental Information letter revises the written description of the proposed changes pertaining to the Notes for SR 3.8.1.2 and SR 3.8.1.19. Attachment 1 to this letter provides the revised Section 2.0 and supersedes Section 2.0 of the referenced document in its entirety.

CEG has reviewed the information supporting a finding of no significant hazards consideration and the environmental consideration provided to the NRC in the referenced document. The supplemental information provided in this letter does not affect the bases for concluding that the proposed license amendment does not involve a significant hazards consideration.

Furthermore, the supplemental information provided in this letter does not affect the bases for

U.S. Nuclear Regulatory Commission Supplemental Information Revise Surveillance Requirements for EDGs Docket No. 50-410 October 28, 2022 Page 2 concluding that neither an environmental impact statement nor an environmental assessment needs to be prepared in connection with the proposed amendment.

There are no regulatory commitments contained in this supplement.

In accordance with 10 CFR 50.91, "Notice for public comment; State consultation," paragraph (b), CEG is notifying the State of New York of this application of license amendment by transmitting a copy of this letter and its attachments to the designated State Official.

If you should have any questions concerning this submittal, please contact Ron Reynolds at ronnie.reynolds@constellation.com.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 28th day of October 2022.

Respectfully, David T. Gudger Senior Manager, Licensing Constellation Energy Generation, LLC

Attachment:

1) Supplemental Information cc: USNRC Regional Administrator, Region I w/attachments USNRC Project Manager, NMP w/attachments USNRC Senior Resident Inspector, NMP w/attachments A. L. Peterson, NYSERDA w/attachments B. Frymire, NYSPSC w/attachments

Supplemental Information Attachment 1 Revise Surveillance Requirements for EDGs Page 1 of 2 Docket No. 50-410 SUPPLEMENTAL INFORMATION This Supplemental Information provides clarification and addresses inconsistencies with the written description of proposed changes in Section 2.0 of the referenced document and the proposed changes illustrated in the marked up technical specification pages in Attachment 2 of the referenced document. Specifically, NMP2 will follow the wording in NUREG-1434, Revision 5, NUREG SR 3.8.1.2 and NUREG SR 3.8.1.7, for NMP2 SR 3.8.1.2 and NMP2 SR 3.8.1.19, respectively, with one variation. In NUREG-1434, Note 2 of NUREG SR 3.8.1.2 is identified as bracketed text. This Note will be applied to NMP2 SR 3.8.1.2 with an administrative variation as the SR numbering for NMP2 does not match the NUREG.

Section 2.0 of the referenced document (ML22144A018) will be replaced in its entirety with the following:

2.0 DETAILED DESCRIPTION Industry experience, as well as industry and NRC-sponsored studies and correspondences over the years have indicated that EDGs are tested too often and that the frequency of surveillance testing can, and does, cause accelerated wear possibly leading to premature emergency diesel generator failures and reducing equipment reliability. Therefore, the proposed changes will implement the recommended testing approach and will bring NMP2 into alignment with NUREG-1434, Volumes 1 and 2, Revision 5 (References 6.2 and 6.3, respectively), including following the guidance of Regulatory Guide (RG) 1.9, "Selection, Design, Qualification, and Testing of Emergency Diesel Generator Units Used as Class 1E Onsite Electric Power Systems at Nuclear Power Plants," Revision 3 (Reference 6.4).

The proposed change will revise NMP2 TS SR 3.8.1.2 to remove and relocate the "Fast-Start" test requirements for the EDGs into a separate SR. This proposed change will align NMP2 SR 3.8.1.2 with the "Start Test" described in Section 2.2.1 of Reference 6.4, and with SR 3.8.1.2 in Reference 6.2. The relocated "Fast-Start" testing requirements will be in a new SR (SR 3.8.1.19) and will align with the "Fast-Start" test as described in References 6.2 and 6.4.

SR 3.8.1.2 will be revised as follows:

Verify each required DG starts from standby conditions and achieves steady state voltage 3950 V and 4370 V and frequency 58.8 Hz and 61.2 Hz.

Also, a second Note will be added that reads, "A modified DG start involving idling and gradual acceleration to synchronous speed may be used for this SR as recommended by the manufacturer. When modified start procedures are not used, the time, voltage, and frequency tolerances of SR 3.8.1.19 must be met."

The frequency for this Surveillance Requirement will remain as described in accordance with the Surveillance Frequency Control Program (SFCP).

Supplemental Information Attachment 1 Revise Surveillance Requirements for EDGs Page 2 of 2 Docket No. 50-410 The new SR 3.8.1.19 will read as follows:

Verify each required DG starts from standby conditions and achieves:

a. In 10 seconds, voltage 3950 V for Division 1 and 2 DGs and 3820 V for Division 3 DG, and frequency 58.8 Hz for Division 1 and 2 DGs and 58.0 Hz for Division 3 DG; and

b. Steady state voltage 3950 V and 4370 V and frequency 58.8 Hz and 61.2 Hz.

A Note will be added to the SR that reads, "All DG starts may be preceded by an engine prelube period."

The frequency for this Surveillance Requirement will be in accordance with the SFCP.

The proposed changes in this License Amendment Request (LAR) to separate the "Start Test" from the "Fast-Start" test will optimize the EDG testing strategy to minimize stress and wear on the EDGs. A modification will be implemented under the 50.59 process to support the testing changes. Until the EDG modifications are in place, EDG testing will continue with manufacturer recommended start procedures as described in proposed Note 2 of TS SR 3.8.1.2.

In addition, a footnote on TS page 3.8.1-6 that reads, "*Following return to OPERABILITY of the HPCS System, the past due Surveillances will be completed by January 18, 2019," will be deleted as that Surveillance was completed as part of the actions associated with Emergency License Amendment 174 for a one-time extension to the Completion Time for LCO 3.5.1, Required Action B.2. provides the marked-up TS pages with the proposed changes indicated. provides marked-up TS Bases pages with the proposed change indicated and are provided for information only.