ML090640936

Request for Additional Information Regarding Steam Generator Tube Inspection Report for Cycle 8

ML090640936
Person / Time
Site:	Watts Bar
Issue date:	03/09/2009
From:	John Lamb Watts Bar Special Projects Branch
To:	Swafford P Tennessee Valley Authority
Lamb John G./NRR/DORL, 415-3100
References
TAC MD9709
Download: ML090640936 (3)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 r'1arch 9, 2009 Mr. Preston D. Swafford Chief Nuclear Officer and Executive Vice President Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 SUB"IECT: WATTS BAR NUCLEAR PLANT, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING STEAM GENERATOR TUBE INSPECTION REPORT FOR CYCLE 8 (TAC NO. MD9709)

Dear Mr. Swafford:

By letters dated June 24, and September 11,2008, Tennessee Valley Authority (TVA) submitted information pertaining to the cycle 8 steam generator tube inspections for Watts Bar Nuclear Plant, Unit 1.

The staff has reviewed the information provided by TVA and has determined that additional information is required to complete its review. The specific questions are detailed in the enclosed request for additional information (RAI). Based on discussions with your staff, we understand that you plan to respond to the enclosed RAI within 30 days of the date of this letter.

If you have any questions regarding this issue, please feel free to contact me at (301) 415-3100.

J G. Lamb, Senior Project Manager

\f1I tts Bar Special Projects Branch OJ ision of Operating Reactor Licensing ffice of Nuclear Reactor Regulation Docket No. 50-390

Enclosure:

RAI cc w/encl: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION REGARDING STEAM GENERATOR TUBE INSPECTION REPORT FOR CYCLE 8 WATTS BAR NUCLEAR PLANT, UNIT 1 TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-390 By letters dated June 24, 2008 (Agencywide Document and Management System Accession No. ML081840101), and September 11, 2008 (ML082600068), Tennessee Valley Authority submitted information pertaining to the cycle 8 steam generator (SG) tube inspections for Watts Bar Nuclear Plant, Unit 1 (WBN-1).

The U.S. Nuclear Regulatory Commission (NRC) staff is reviewing this information, and has determined that additional information is necessary for the staff to complete its review.

1. Please provide the cumulative effective full power months that the SGs had operated at the time of the WBN-1 2008 refueling outage.

2. Please provide a general description of WBN-1 replacement SGs. Please include in this response the following information regarding the design of your replacement SGs:

(i) the tubesheet thickness (with and without clad); (ii) the method used to expand the tubes into the tubesheet and the extent of expansion; (iii) the extent to which any tubes were stress-relieved following bending; (iv) the radius of the smallest radius tubes; (v) the tube support plate thickness, material of construction, and hole configuration (including the flow distribution baffle, if any); (vi) the anti-vibration bar cross section (e.g.,

rectangular), material of construction and the depth of penetration of the anti-vibration bars; (vii) the tube pitch (e,g., 1.0 triangular); and (viii) the tube and SG fabricator. In addition, please provide a tubesheet map and a sketch of the SG showing the tube support naming convention.

3. Regarding the scope of WBN-1 inspections, discuss whether any secondary side inspections (including foreign object search and retrieval inspections) were performed. If so, discuss the results, If any loose parts or degraded conditions were identified, please discuss the actions taken to ensure acceptable SG performance until the next scheduled inspection, Enclosure

March 9, 2009 Mr. Preston D. Swafford Chief Nuclear Officer and Executive Vice President Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 SUB,JECT: WATTS BAR NUCLEAR PLANT, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING STEAM GENERATOR TUBE INSPECTION REPORT FOR CYCLE 8 (TAC NO. MD9709)

Dear Mr. Swafford:

By letters dated June 24, and September 11,2008, Tennessee Valley Authority (TVA) submitted information pertaining to the cycle 8 steam generator tube inspections for Watts Bar Nuclear Plant, Unit 1.

The staff has reviewed the information provided by TVA and has determined that additional information is required to complete its review. The specific questions are detailed in the enclosed request for additional information (RAI). Based on discussions with your staff, we understand that you plan to respond to the enclosed RAI within 30 days of the date of this letter.

If you have any questions regarding this issue, please feel free to contact me at (301) 415-3100.

Sincerely, IRA!

John G. Lamb, Senior Project Manager Watts Bar Special Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-390

Enclosure:

RAI cc w/encl: Distribution via Listserv Docket No. 50-390

Enclosure:

RAI cc w/encl: Distribution via Listserv DISTRIBUTION:

PUBLIC RidsOgcRp Resource LPL-Wb rlf RidsAcrs_MailCTR Resource RidsNrrDorlLp-Wb Resource RidsRgn2MailCenter Resource RidsNrrLABClayton Resource RidsNrrDirsltsb Resource RidsNrrPMJLamb Resource RidsNrrPMPMilano Resource RidsNrrDciCsgb ADAMS Accession Number* ML090640936 *via memorandum OFFICE LP-WBB/PM LP-WB/LA CSGB/BC (A) LP-WB/BC NAME JLamb BClayton MYoder* LRaghavan DATE 3/9/09 3/6/09 03/05/09 3/9/09 OFFICIAL RECORD COPY