ML18207A436

NRR E-mail Capture - Wolf Creek Verbal Relief Request - Relief from American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) Code Case N-666-1 for Alternate Repair of Essential Service Water Piping

ML18207A436
Person / Time
Site:	Wolf Creek
Issue date:	07/26/2018
From:	Balwant Singal Plant Licensing Branch IV
To:	Hafenstine C, Sweet S Wolf Creek
References
L-2018-LLR-0101
Download: ML18207A436 (5)

Text

NRR-DMPSPEm Resource From: Singal, Balwant Sent: Thursday, July 26, 2018 10:42 AM To: Sweet Sheryl A; Hafenstine Cynthia R; Rudeen Jim K Cc: Ruffin, Steve; Pascarelli, Robert; Taylor, Nick; Tsao, John

Subject:

Wolf Creek Verbal Relief Request - Relief from American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) Code Case N-666-1 for Alternate Repair of Essential Service Water Piping Attachments: Wolf Creek Verbal Authorization Script.docx By telephone on July 24, 2018, the U.S. Nuclear Regulatory Commission (NRC) staff provided verbal authorization to Wolf Creek Nuclear Operating Corporation (WCNOC, the licensee) for the subject relief request based on the attached explanation.

Participants:

NRC Steve Ruffin, Chief (provided technical justification)

Robert Pascarelli, Chief (provided authorization)

John Tsao, Senior Materials Engineer Nick Taylor, Chief, Region IV James Drake, Chief, Region IV Balwant K. Singal, Senior Project Manager WCNOC Cindy Hafenstine, Manager Regulatory Affairs Paul Herrman, Manager Design Engineering Daniel Bowers, Manager Maintenance Daljit Mand, Director Engineering Eric Carlson, Superintendent Operations Bill Stucker, Superintendent Operations Support Jeff Isch, Superintendent Operations Work Controls Matt Legresley, Supervisor Engineering Jim Rudeen, Supervisor Regulatory Affairs Kyle Hinteweger, Supervisor Engineering Dave Meredith, Principle Engineer Allen Barraza, Engineer II Sherri Sweet, Licensing Engineer Please let me know if you have any questions.

Thanks.

Balwant K. Singal Senior Project Manager (Diablo Canyon and Wolf Creek)

Nuclear Regulatory Commission Division of Operating Reactor Licensing Balwant.Singal@nrc.gov Tel: (301) 415-3016 1

Fax: (301) 415-1222 2

Hearing Identifier: NRR_DMPS Email Number: 493 Mail Envelope Properties (Balwant.Singal@nrc.gov20180726104100)

Subject:

Wolf Creek Verbal Relief Request - Relief from American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) Code Case N-666-1 for Alternate Repair of Essential Service Water Piping Sent Date: 7/26/2018 10:41:42 AM Received Date: 7/26/2018 10:41:00 AM From: Singal, Balwant Created By: Balwant.Singal@nrc.gov Recipients:

"Ruffin, Steve" <Steve.Ruffin@nrc.gov>

Tracking Status: None "Pascarelli, Robert" <Robert.Pascarelli@nrc.gov>

Tracking Status: None "Taylor, Nick" <Nick.Taylor@nrc.gov>

Tracking Status: None "Tsao, John" <John.Tsao@nrc.gov>

Tracking Status: None "Sweet Sheryl A" <shsweet@WCNOC.com>

Tracking Status: None "Hafenstine Cynthia R" <cyhafen@WCNOC.com>

Tracking Status: None "Rudeen Jim K" <jarudee@WCNOC.com>

Tracking Status: None Post Office:

Files Size Date & Time MESSAGE 1344 7/26/2018 10:41:00 AM Wolf Creek Verbal Authorization Script.docx 23063 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received:

VERBAL AUTHORIZATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST FROM ASME CODE N-666-1 ALTERNATE REPAIR OF ESSENTIAL SERVICE WATER PIPING WOLF CREEK GENERATING STATION, Unit 1 DOCKET NO. 50-482 JULY 24, 2018 Technical Evaluation read by Steve Ruffin, Chief of the Piping and Head Penetration Branch, NRR By letter dated July 23, 2018, with supplement dated July 24, 2018, Wolf Creek Nuclear Operating Corporation (the licensee) requested relief from the requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),Section XI, IWA-4000 at Wolf Creek Generating Station Unit 1.

Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(z)(2), the licensee submitted Relief Request From ASME Code N-666-1 to repair a leaking 2-inch socket weld on the essential service water (ESW) piping using ASME Code Case N-666-1 Weld Overlay of Class 1, 2, and 3 Socket Welded ConnectionsSection XI, Division 1.

The licensee states that it will follow all the provisions of Code Case N-666-1 to install a weld overlay on the leaking socket weld except that the licensee asked for relief from the following:

1) paragraph 1(b) of code case that requires the pipe material be less than 0.30% carbon content;

2) pipe minimum wall thickness adjacent to the socket weld in paragraph 1(d) of the code case; and

3) non-vibrational fatigue degradation mechanism.

The NRC staff determines that (1) the technical basis for the welding on pipe material having a carbon content of 0.32% is acceptable, (2) it is acceptable that the proposed weld overlay is designed to support piping loads without crediting the existing pipe base material, (3) the licensee will follow the condition imposed on Code Case N-666-1 in Regulatory Guide 1.147 that requires a surface examination on the final layer, (4) the proposed walk down every 12-hour shift post installation is acceptable to monitor the repaired socket weld, and (5) the licensees hardship justification is adequate.

The NRC finds that the licensee has demonstrated that the proposed alternative will provide reasonable assurance of the structural integrity of the subject socket weld on the ESW piping for the short duration until the fall of 2019.

Authorization read by Robert Pascarelli, Chief of the Plant Licensing Branch IV, NRR As Chief of the Plant Licensing Branch IV, Office of Nuclear Reactor Regulation, I concur with the conclusions of the Piping and Head Penetration Branch.

The NRC staff determines that the proposed alternative provides reasonable assurance of structural integrity of the repaired socket weld on the ESW piping. The NRC staff finds that complying with IWA-4000 of the ASME Code,Section XI, would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)(2). Therefore, on July 24, 2018, the NRC

authorizes the use of the subject relief request at Wolf Creek Generating Station, Unit 1 through refueling outage 23, scheduled for the fall of 2019.

All other requirements in ASME Code,Section XI, for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.

This verbal authorization does not preclude the NRC staff from asking additional clarification questions regarding the Relief Request while preparing subsequent written safety evaluation.