ML22132A043

Operating Corporation (WCNOC) - Withdrawal of 10 CFR 50.55a Request I4R-09, Relief from Examination of Reactor Vessel Flange Threads

ML22132A043
Person / Time
Site:	Wolf Creek
Issue date:	05/12/2022
From:	Boyce M Wolf Creek
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
22-0009
Download: ML22132A043 (2)

Text

Michael T. Boyce Vice President Engineering

May 12, 2022 ET 22-0009

U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Reference:

Letter ET 22-0003, dated April 6, 2022, from M. T. Boyce, WCNOC, to USNRC

Subject:

Docket No. 50-482: Withdrawal of 10 CFR 50.55a Reque st I4R-09, Relief from Examination of Reactor Vessel Flange Threads

Commissioners and Staff:

The purpose of this submittal is to withdraw Wolf Creek Nuclear Operating Corporation (WCNOC) 10 CFR 50.55a Request originally provided by the Reference. Th e Reference transmitted 10 CFR 50.55a Request I4R-09 for an alternative to the requirement of the American Society of Mechanical Engineers (ASME) Code,Section XI, Examination Categ ory B-G-1, Item Number B6.40, Threads in Flange, to perform ultrasonic examinations of threads in reactor pressure vessel closure flange connections every inservice inspection (I SI) interval. Nuclear Regulatory Commission (NRC) Regulatory Guide (RG) 1.147, Revision 20 was e ffective as of April 4, 2022.

In this revision, ASME Section XI Code Case N-864 was condition ally approved by the NRC.

Code Case N-864 allows that reactor pressure vessel threads in flange examinations be performed in at least every third 10-year ISI interval. The co nditions include that monitoring and maintenance activities must be performed and documented to moni tor the condition of the reactor pressure vessel threads in flange for signs of degradation and to mitigate any degradation that occurs. WCNOC plans to evaluate the use of this Code Case and implement appropriate necessary actions to meet these conditions. Therefore, WCNOC i s withdrawing the proposed request and is no longer seeking NRC review and approval of I4R -09.

P.O. Box 411 l Burlington, KS 66839 l 620-364-8831 ET 22-0009 Page 2 of 2

This letter contains no commitments. If you have any questions concerning this matter, please contact me at (620) 364-8831 x8687, or Ron Benham at (620) 364-4204.

Sincerely,

Michael T. Boyce

MTB/rlt

cc: S. S. Lee (NRC)

S. A. Morris, (NRC)

G. E. Werner (NRC)

Senior Resident Inspector (NRC)