ML16008A981

Review of the Spring 2015 Steam Generator Tube Eddy Current Test Report

ML16008A981
Person / Time
Site:	Fort Calhoun
Issue date:	01/15/2016
From:	Lyon C Plant Licensing Branch IV
To:	Cortopassi L Omaha Public Power District
Lyon C, NRR/DORL/LPLIV-1
References
CAC MF7137
Download: ML16008A981 (4)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 January 15, 2016 Mr. Louis P. Cortopassi Site Vice President and Chief Nuclear Officer Omaha Public Power District Fort Calhoun Station 9610 Power Lane, Mail Stop FC-2-4 Blair, NE 68008

SUBJECT:

FORT CALHOUN STATION, UNIT NO. 1 - REVIEW OF THE 2015 STEAM GENERATOR TUBE EDDY CURRENT TEST REPORT (CAC NO. MF7137)

Dear Mr. Cortopassi:

By letter to the U.S. Nuclear Regulatory Commission (NRC) dated November 24, 2015, Omaha Public Power District (OPPD, the licensee), submitted information summarizing the results of the steam generator tube inspections performed at Fort Calhoun Station, Unit 1 (FCS), during refueling outage 27 in the spring of 2015. A conference call between the licensee and NRC staff during your inspection was documented in the NRC letter dated June 10, 2015. Your report was submitted in accordance with Technical Specification (TS) 3.17(3), "Steam Generator (SG) Tube Integrity Reporting Requirements."

Based on its review, the NRC staff concludes that the licensee has provided the information required by TS 3.17(3), and no follow-up is required at this time. A summary of the NRC staff's review is enclosed. If you have any questions, please contact me at 301-415-2296 or via e-mail at Fred.Lyon@nrc.gov.

Sincerely, Carl F. Lyon, Project Manager Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-285

Enclosure:

As stated cc w/encl: Distribution via Listserv

SUMMARY

OF THE REVIEW OF THE 2015 REFUELING OUTAGE 27 STEAM GENERATOR TUBE EDDY CURRENT TEST REPORT OMAHA PUBLIC POWER DISTRICT FORT CALHOUN STATION, UNIT NO. 1 DOCKET NO. 50-285 By letter to the U.S. Nuclear Regulatory Commission (NRC) dated November 24, 2015 (Agencywide Documents Access and Management System Accession No. ML15328A491 ),

Omaha Public Power District (OPPD, the licensee), submitted information summarizing the results of the steam generator (SG) tube inspections performed at Fort Calhoun Station, Unit No. 1 (FCS), during refueling outage 27 (RF027) in the spring of 2015. A conference call between the licensee and NRC staff during the inspection was documented in the NRC's letter dated June 10, 2015 (ADAMS Accession No. ML15160A281). The licensee's information was submitted in accordance with FCS Technical Specification (TS) 3.17(3), "Steam Generator (SG)

Tube Integrity Reporting Requirements."

FCS has two re-circulating SGs designed and manufactured by Mitsubishi Heavy Industries, and designated model MHl-49TT-1. Each SG contains 5,200 thermally treated Alloy 690 tubes with a nominal outside diameter of 0.750 inches and a nominal wall thickness of 0.043 inches.

Five stainless steel tube support plates (TSPs) support the vertical section of the tubes and 10 anti-vibration bars (AVBs) provide support in the U-bend section of the tubes. Both the TSPs and AVBs are made of Type 405 stainless steel.

The licensee provided the scope, extent, methods, and results of its SG tube inspections in the document referenced above. In addition, the licensee described corrective actions, such as tube plugging, taken in response to the inspection findings.

After reviewing the information provided by the licensee, the NRC staff has the following comments or observations:

• The tubes in both SGs were inspected during RF027.

• The FCS SGs were replaced during its 2006 refueling outage. The first inservice inspection was performed in 2008. Due to an extended shutdown in 2011, the FCS SGs had only accumulated 5.22 effective full power years of operation by RF027.

• TSP wear was reported at FCS for the first time in RF027. Twenty-seven indications were reported in 10 tubes in SG A and 28 indications were reported in nine tubes in SG B. None of the indications met the plugging criteria, so no tubes were plugged.

Enclosure

Based on a review of the information provided, the NRC 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 since the inspections appear to be consistent with the objective of detecting potential tube degradation and the inspection results appear to be consistent with industry operating experience at similarly designed and operated units.

ML16008A981 *memo dated OFFICE NRR/DORULPL4-1/PM N RR/DOR ULPL4-1 /LA NRR/DE/ESGB/BC* NRR/DORL/LPL4-1/BC NRR/DORULPL4-1 /PM NAME FL yon JBurkhardt GKulesa RPascarelli FL yon DATE 1/11/16 1/11/16 12/23/15 1/14/16 1/15/16