ML19052A004

Review of Steam Generator Inservice Inspection Report for Unit 3 End of Cycle 29 Refueling Outage

ML19052A004
Person / Time
Site:	Oconee
Issue date:	02/26/2019
From:	Audrey Klett Plant Licensing Branch II
To:	Burchfield J Duke Energy Carolinas
Klett A, NRR/DORL/LPL2-1, 415-0489
References
EPID L-2018-LRO-0030
Download: ML19052A004 (3)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 February 26, 2019 Mr. J. Ed Burchfield, Jr.

Vice President, Oconee Nuclear Station Duke Energy Carolinas, LLC 7800 Rochester Highway Seneca, SC 29672-0752

SUBJECT:

OCONEE NUCLEAR STATION, UNIT 3- REVIEW OF STEAM GENERATOR INSERVICE INSPECTION REPORT FOR UNIT 3 END OF CYCLE 29 REFUELING OUTAGE (EPID L-2018-LR0-0030)

Dear Mr. Burchfield:

By letter RA-18-0138 dated August 15, 2018, Duke Energy Carolinas, LLC (the licensee) submitted its steam generator tube inspection report for Oconee Nuclear Station, Unit 3 (Oconee 3) in accordance with Technical Specification (TS) 5.6.8, "Steam Generator Tube Inspection Report." The report summarizes the steam generator tube inspections that the licensee performed during the Oconee 3 Cycle 29 refueling outage in the spring of 2018. The U.S. Nuclear Regulatory Commission (NRC) staff reviewed the submittal and concludes that the licensee provided the information required by TS 5.6.8. The enclosure documents the NRC staff's review of the submittal and completes the NRC staff's efforts for Enterprise Project Identifier (EPID) L-018-LR0-0030. Any inquiries can be directed to Ms. Audrey Klett at 301-415-0489 or via e-mail at ::-:=.:::.:...::c.,..:.::...:.:.==..:_:.:_;=;;;_:.

Sincerely, Audrey Klett, Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-287

Enclosure:

As stated cc Listserv

REVIEW BY THE OFFICE OF NUCLEAR REACTOR REGULATION SPRING 2018 STEAM GENERATOR TUBE INSERVICE INSPECTION REPORT DUKE ENERGY CAROLINAS, LLC OCONEE NUCLEAR STATION, UNIT 3 DOCKET NO. 50-287 By letter RA-18-0138 dated August 15, 2018 (Agencywide Documents Access and Management Systems Accession No. ML18235A502), Duke Energy Carolinas, LLC (the licensee) submitted information summarizing the results of the steam generator (SG) tube inspections performed at Oconee Nuclear Station, Unit 3 (Oconee 3), during refueling outage (RFO) 29 in the spring of 2018. Oconee 3 is a two-loop pressurized-water reactor with replacement once-through steam generators (ROTSGs) manufactured by Babcock & Wilcox (B&W), Canada. The licensee installed the ROTSGs during the fall 2004 refueling outage. The ROTSGs contain 15,631 thermally treated Alloy 690 tubes that have been hydraulically expanded into the tubesheet to a depth of 13 inches. Tube support is provided by 15 Type 410 stainless steel tube support plates (TSP) of trifoil broach design; however, there are some round drilled openings at the 14th TSP.

The licensee provided the scope, extent, methods, and results of its SG tube inspections in its letter dated August 15, 2018. In addition, the licensee described corrective actions (e.g., tube plugging) taken in response to the inspection findings. The first inservice inspection of the ROTSGs at Oconee 3 in the spring of 2006 revealed widespread TSP wear degradation of the tubing at TSP locations. Oconee 1 and 2 have also experienced this widespread TSP wear degradation. The licensee has managed this degradation with no loss of tube integrity.

Based on a review of the information provided, the U.S. Nuclear Regulatory Commission staff concludes that the licensee provided the information required by its Technical Specifications. In addition, the staff concludes that there are no technical issues that warrant follow-up action at this time because the inspections appear to be consistent with the objective of detecting potential tube degradation. Most of the inspection results appear to be consistent with industry operating experience at similarly designed and operated units (with the exception of the large number of TSP wear indications).

Principal Contributor: A. Johnson, NRR/DMLR/MCCB Date: February 26, 2019 Enclosure

SUBJECT:

OCONEE NUCLEAR STATION, UNIT 3 - REVIEW OF STEAM GENERATOR INSERVICE INSPECTION REPORT FOR UNIT 3 END OF CYCLE 29 REFUELING OUTAGE (EPID L-2018-LR0-0030)

DATED REBRUARY 26, 2019 DISTRIBUTION:

PUBLIC LPLll-1 R/F RidsNrrPMOconee Resource RidsNrrLAKGoldstein Resource RidsNrrDorlLp2-1 Resource RidsACRS_MailCtr Resource RidsRgn2MailCenter Resource RidsNrrDlmrMccb Resource SBloom, NRR/DMLR Paul Klein, NRR/DMLR Alan Huynh, NRR/DMLR Andrew Johnson, NRR/DMLR ADAMS A ccess,on No.: ML19052A004 *b1vema1.,

OFFICE NRR/LPL2-1 /PM NRR/LPL2-1/LA NRR/DMLR/MCCB/BC*

NAME AKlett KGoldstein SBloom DATE 2/19/19 02/25/19 2/14/19 OFFICE NRR/LPL2-1 /BC NRR/LPL2-1/PM NAME MMarkley AKlett DATE 02/26/19 02/26/19 OFFICIAL RECORD COPY