ML091380530

Request for Additional Information for Extended Power Uprate - Round 24 (TAC MD5262) (TS-431)

ML091380530
Person / Time
Site:	Browns Ferry
Issue date:	06/09/2009
From:	Ellen Brown Plant Licensing Branch II
To:	Swafford P Tennessee Valley Authority
Brown, E, NRR/DORL, 415-2315
References
TAC MD5262, TS-431
Download: ML091380530 (4)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 June 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

SUBJECT:

BROWNS FERRY NUCLEAR PLANT, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION FOR EXTENDED POWER UPRATE - ROUND 24 (TAC NO. MD5262) (TS-431)

Dear Mr. Swafford:

By letter dated June 28,2004, the Tennessee Valley Authority (TVA, the licensee) submitted an amendment request for Browns Ferry Nuclear Plant (BFN), Unit 1, as supplemented by letters dated August 23, 2004, February 23, April 25, June 6, December 19, 2005, February 1 and 28, March 7, 9, 23, and 31, April 13, May 5,15, and 16, June 15, 23, and 27, July 6,21,26, and 31, August 4, 16, 18, and 31, September 1, 15, and 22, October 3, 5, and 13, November 7, December 1,5,11, and 21,2006, January 31, February 16 and 26, April 6, 18, and 24, July 27, September 24, November 15 and 21, December 14, 2007, January 25 and 31, February 11 and 21, March 6, April 4 and 9, May 1, June 3,12, and 16, August 15, September 2 and 19, October 3,17, and 31, November 11 and 14, December 15, 2008, January 9,16, and 23, February 18 and 24, March 11, 12, and 27, April 3, 10, 21, and 29, and May 7, 2009. The proposed amendment would change the BFN operating license for Unit 1 to increase the maximum authorized power level by approximately 15 percent.

Enclosed is a non-proprietary version Request for Additional Information (RAI). A proprietary version of the RAI was provided in separate correspondence. Your response to our RAI is needed before the Nuclear Regulatory Commission staff can complete the review. This request was discussed with Mr. Denzel Housely of your staff on May 20, 2009, and it was agreed that TVA would respond by June 5,2009.

If you have any questions, please contact me at (301) 415-2315.

Sincerely, IRA!

Eva A. Brown, Senior Project Manager Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-259

Enclosure:

RAI Non-Proprietary Version cc w/enclosure: Distribution via ListServ

REQUEST FOR ADDITIONAL INFORMATION EXTENDED POWER UPRATE ROUND 24 TENNESSEE VALLEY AUTHORITY (TVA)

BROWNS FERRY NUCLEAR PLANT UNIT 1 DOCKET NO. 50- 259 EMCB (Unit 1 only) 208. It appears that the main steam line (MSL) strain gage measurements in Unit 1 were reduced by subtracting:

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1]

In Enclosure 3 of a letter dated July 27, 2007, the licensee provide acoustic circuit model (ACM), Rev. 4 (described in Continuum Dynamics Incorporated (CDI) Report 07-09P, Rev. 0), which was benchmarked using Quad Cities 2 (QC2) MSL and steam dryer measurements. The licensee used the QC2 benchmark data to compute the frequency dependent bias errors and uncertainties for Unit 1.

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II Address the apparent inconsistency with the conclusion that the CDI 07-09 bias and uncertainties are conservative [1.=[= = = = = = = = = = = = = = = = = =

11 209. While conducting the steam dryer inspections during the Unit 2 Cycle 15 refueling outage, the licensee found the TB-3/4-01, TB-3/4-02, and TB-3/4-03 tie bars to be broken. The inspections also revealed that the TB-5/6-01, TB-5/6-02, and TB-1/2-02 tie bars were bent. Deformation of the center divider plate between banks 3 and 4 was also observed by the licensee. In addition, crack-like indications were noted on the TB-4/5-02 and TB-1/2-01 tie bars. This recent operating experience provides an

-2 opportunity to confirm the accuracy of the current approach of dynamic stress analysis of boiling-water reactor steam dryer using the ACM Revision 4 to predict the dryer pressure loading for each planned dryer configuration for the three Browns Ferry units.

Therefore, TVA is requested to provide a Unit 2 dryer stress analysis for the existing dryer configuration, based on the dryer pressure loading for the current licensed thermal power [105 percent original licensed thermal power], as predicted by the ACM Rev. 4 Code, in order to demonstrate the analytical predictability of the above noted deformations of the tie bars and the center divider plate, as well as failures of certain tie bars.

• ML091380530 NRR-088 OFFICE LPL2-2/PM LPL2-2/LA DElEMCB/BC LPL2-2/BC NAME EBrown BClayton MKhanna TBoyce DATE 06/09/09 06/03/09 06/3109 06/09/09