ML15177A108

Palo Verde Steam Generating Station, Unit 2 - Review of Spring 2014 Steam Generator Tube Inspection Report for Refueling Outage U2R18 (TAC No. MF5053)

ML15177A108
Person / Time
Site:	Palo Verde
Issue date:	06/29/2015
From:	Watford M M Plant Licensing Branch IV
To:	Edington R K Arizona Public Service Co
Watford M M
References
TAC MF5053
Download: ML15177A108 (4)

Text

Mr. Randall Executive Vice President Nuclear/ Chief Nuclear Officer Mail Station 7602 Arizona Public Service Company P.O. Box 52034 Phoenix, AZ 85072-2034 June 29, 2015

SUBJECT: PALO VERDE NUCLEAR GENERATING STATION, UNIT 2 -REVIEW OF THE 2014 STEAM GENERATOR TUBE INSPECTIONS DURING REFUELING OUTAGE 18 (TAC NO. MF5053)

Dear Mr. Edington:

By letter dated October 10, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML 14288A371 ), as supplemented by letter dated April 1, 2015 (ADAMS Accession No. ML 15097A170), Arizona Public Service Company (the licensee) submitted information summarizing the results of the spring 2014 steam generator tube inspections performed at Palo Verde Nuclear Generating Station, Unit 2. These inspections were performed during refueling outage 18 (RFO 18). By letter dated June 2, 2014 (ADAMS Accession No. ML14150A177), the U.S. Nuclear Regulatory Commission (NRC) staff summarized a conference call that was held with the licensee during RFO 18. The NRC staff has completed its review of the submittals and concludes that the licensee provided the information required by its technical specifications. In addition, the NRC staff concludes that there are no technical issues that warrant follow-up actions at this time. The staff's review of the reports is enclosed. If you have any questions, please contact me at (301) 415-1233 or via e-mail at Margaret. Watford@nrc.gov.

• Docket No. STN 50-529

Enclosure:

As stated cc w/encl: Distribution via Listserv

Sincerely,Margaret M. Watford, Project Manager Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation STAFF REVIEW OF RESULTS OF SPRING 2014 STEAM GENERATOR TUBE INSERVICE INSPECTIONS PERFORMED DURING REFUELING OUTAGE 18 ARIZONA PUBLIC SERVICE COMPANY PALO VERDE NUCLEAR GENERATING STATION, UNIT 2 DOCKET NO. STN 50-529 By letter dated October 10, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML 14288A371 ), as supplemented by letter dated April 1, 2015 (ADAMS Accession No. ML 15097A170), Arizona Public Service Company (the licensee) submitted information summarizing the results of the spring 2014 steam generator (SG) tube inspections performed at Palo Verde Nuclear Generating Station (PVNGS), Unit 2. These inspections were performed during refueling outage 18 (RFO 18). By letter dated June 2, 2014 (ADAMS Accession No. ML 14150A177), the U.S. Nuclear Regulatory Commission staff summarized a conference call that was held with the licensee during RFO 18 regarding the spring 2014 SG tube inspection activities. PVNGS, Unit 2 has two replacement SGs designed by Combustion Engineering and fabricated by Ansaldo Energia. Each steam generator has 12,580 thermally treated Alloy 690 tubes with a nominal outside diameter of 0.750 inches and a nominal wall thickness of 0.042 inches. The tubes are arranged in a triangular pitch with 0.866-inch spacing. The tubes were hydraulically expanded at each end for the full depth of the tubesheet. The tubes are supported by horizontal lattice grid supports, batwing (diagonal) supports, and vertical straps. All tube supports are constructed from Type 409 stainless steel. The licensee provided the scope, extent, methods, and results of its SG tube inspections in the documents referenced above. In addition, the licensee described corrective actions (i.e., tube plugging) taken in response to the inspection findings. 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 NRC 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. Enclosure