ML042870005

Steam Generator Tube Inspection

ML042870005
Person / Time
Site:	Vogtle
Issue date:	10/07/2004
From:	Gratton C NRC/NRR/DLPM/LPD2
To:	Gasser J Southern Nuclear Operating Co
Gratton C, NRR/DLPM, 415-1055
References
Download: ML042870005 (5)

Text

October 7, 2004 Mr. J. T. Gasser Vice President Southern Nuclear Operating Company, Inc.

Post Office Box 1295 Birmingham, Alabama 35201-1295

SUBJECT:

VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2 - STEAM GENERATOR TUBE INSPECTION RESULTS FOR FALL 2002 AND FALL 2003 OUTAGES (TAC NOS. MC1979 AND MC1980)

Dear Mr. Gasser:

By letters to the U.S. Nuclear Regulatory Commission (NRC) dated October 31, 2002, February 4, 2003, October 27, 2003, January 16, 2004, and August 26, 2004, Southern Nuclear Operating Company Inc. (the licensee), submitted reports and provided additional information pertaining to their steam generator tube inspections at Vogtle Electric Generating Plant, Units 1 and 2, for their fall 2003 and fall 2002 outages, respectively, in accordance with the plants Technical Specifications (TSs). The NRC staff has completed its review of the licensees inservice inspection reports and concludes that the licensee has provided the information required by the TSs and that no additional follow-up is required at this time. A copy of the NRC staffs review is enclosed.

Sincerely,

/RA/

Christopher Gratton, Sr. Project Manager Section 1 Project Directorate II Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-424 and 50-425

Enclosure:

As stated cc w/encl: See next page

ML042870005 NRR-106 OFFICE PDII-1/PM PDII-1/LA (A) EMCB/SC PDII-1/SC (A)

NAME CGratton DClarke ALund* MRoss-Lee DATE 10/6/04 10/5/04 9/16/04 10/7/04 DISTRIBUTION FOR VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2 - STEAM GENERATOR TUBE INSPECTION RESULTS FOR FALL 2002 AND FALL 2003 OUTAGES (TAC NOS. MC1979 AND MC1980)

Dated: October 7, 2004 DISTRIBUTION:

PUBLIC PDII R/F RidsNrrPMCGratton RidsNrrLACHawes/DClarke RidsRgn2MailCenter (BBonser)

JNakoski/MJRoss-Lee RidsOgcRp RidsAcrsAcnwMail RidsNrrDlpmDpr RidsDeDpr LLund MMurphy YDiaz

REVIEW OF THE 2002/2003 STEAM GENERATOR TUBE INSPECTION REPORTS VOGTLE ELECTRIC GENERATING PLANT UNITS 1 & 2 DOCKET NOS. 50-424 AND 50-425 By letters to the U.S. Nuclear Regulatory Commission (NRC) dated October 31, 2002 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML023110389), February 4, 2003 (ML030410264), October 27, 2003 (ML033030404),

January 16, 2004 (ML040220620), and August 26, 2004 (ML042430424), Southern Nuclear Operating Company Inc. (the licensee), submitted information pertaining to their 2002 Unit 2 (2R9) and 2003 Unit 1 (1R11) steam generator (SG) tube inspections at Vogtle Electric Generating Plant (Vogtle). ADAMS documents can be viewed on the Nuclear Regulatory Commission (NRC) website, www.nrc.gov, in the Electronic Reading Room, under Documents in ADAMS, by selecting Web Based Access and entering the applicable accession number.

Vogtle, Units 1 and 2 have four Westinghouse Model F SGs each. There are 5626 thermally treated Alloy 600 tubes in each of the SGs. The tubes have an outside diameter of 11/16 inch, a wall thickness of 0.040-inch, and are supported by seven stainless steel tube support plates (TSPs) and a flow distribution baffle. The TSP holes are quatrefoil shaped. The U-bend region of the tubes in rows 1 through 10 was stress relieved after bending.

Of particular note from the outages is that the licensee performed a quatrefoil blockage assessment and an evaluation of the effects of the phosphate chemistry excursion that occurred in 2002 at Vogtle, Units 1 and 2. The results for the quatrefoil blockage assessment were: (1) no clean tube to TSP intersections were observed, (2) scale is significantly thicker at the bottom of the TSP than at the top, and (3) more deposits are observed in intersections at TSP7 than at other TSPs (TSP7 is the uppermost tube support). For the evaluation of the effects of the phosphate chemical excursion, the licensee inspected 100 percent of the tubes with a bobbin probe and inspected 50 percent of the tubes at the top of the hot leg tubesheet with a +Point probe. In addition, the licensee performed an analysis and history comparison to identify any excursion signals that could indicate the possible onset of corrosion. None were identified. Additional details on the phosphate chemical excursion can be found in an NRC letter dated April 24, 2003 (ML031150065).

The licensee provided the scope, extent, methods and results of their SG tube inspections in the documents referenced above. In addition, the licensee described corrective actions (i.e., tube plugging or repair) taken in response to the inspection findings.

Enclosure

Based on a review of the information provided, the NRC staff concludes that the licensee provided the information required by their 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.

Vogtle Electric Generating Plant cc:

Mr. N.J. Stringfellow Harold Reheis, Director Manager, Licensing Department of Natural Resources Southern Nuclear Operating 205 Butler Street, SE. Suite 1252 Company, Inc. Atlanta, Georgia 30334 P. O. Box 1295 Birmingham, Alabama 35201-1295 Attorney General Law Department Mr. Skip Kitchens 132 Judicial Building General Manager, Vogtle Electric Atlanta, Georgia 30334 Generating Plant Southern Nuclear Operating Mr. Laurence Bergen Company, Inc. Oglethorpe Power Corporation P. O. Box 1600 2100 East Exchange Place Waynesboro, Georgia 30830 P. O. Box 1349 Tucker, Georgia 30085-1349 Mr. J. Gasser Executive Vice President Arthur H. Domby, Esquire Southern Nuclear Operating Troutman Sanders Company, Inc. NationsBank Plaza P. O. Box 1295 600 Peachtree Street, NE.

Birmingham, Alabama 35201-1295 Suite 5200 Atlanta, Georgia 30308-2216 Steven M. Jackson Senior Engineer - Power Supply Resident Inspector Municipal Electric Authority Vogtle Plant of Georgia 8805 River Road 1470 Riveredge Parkway, NW. Waynesboro, Georgia 30830 Atlanta, Georgia 30328-4684 Office of the County Commissioner Mr. Reece McAlister Burke County Commission Executive Secretary Waynesboro, Georgia 30830 Georgia Public Service Commission 244 Washington St., S. W.

Atlanta, Ga. 30334