ML11158A017

Submittal of Annual Report of Changes or Errors Discovered in the Emergency Core Cooling System Evaluation Model

ML11158A017
Person / Time
Site:	Browns Ferry
Issue date:	06/03/2011
From:	Krich R Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML11158A017 (6)

Text

Tennessee Valley Authority 1101 Market Street, LP 3R Chattanooga, Tennessee 37402-2801 R. M. Krich Vice President Nuclear Licensing June 3, 2011 10 CFR 50.4 10 CFR 50.46 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Browns Ferry Nuclear Plant, Units 1, 2, and 3 Facility Operating License Nos. DPR-33, DPR-52, and DPR-68 NRC Docket Nos. 50-259, 50-260, and 50-296

Subject:

10 CFR 50.46 Annual Report

References:

1) TVA Letter to NRC, "Final Report of Emergency Core Cooling System Evaluation Model Changes," dated April 30, 2010 (Unit 1)

2) TVA Letter to NRC, "Final Report of Emergency Core Cooling System Evaluation Model Changes," dated April 30, 2010 (Units 2 and 3)

The purpose of this letter is to provide the annual report of changes or errors discovered in the emergency core cooling system (ECCS) evaluation model for Browns Ferry Nuclear Plant, Units 1, 2, and 3. In accordance with 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling Systems for Light-Water Nuclear Power Reactors,"

paragraph (a)(3)(ii), the enclosed report describes the nature and the estimated effect on the limiting ECCS analysis of changes or errors discovered since submittal of the reference letters.

printed on recycled paper

U.S. Nuclear Regulatory Commission Page 2 June 3, 2011 This report is normally submitted by the end of April each year and is therefore late due to an administrative deficiency. This issue has been documented in our Corrective Action Program. There are no regulatory commitments in this letter. Please direct questions concerning this issue to Tom Matthews at (423) 751-2687.

Respectfully, .

R. M. Krich

Enclosure:

10 CFR 50.46 Annual Report cc (Enclosure): NRC Regional Administrator - Region II NRC Senior Resident Inspector - Browns Ferry Nuclear Plant

ENCLOSURE BROWNS FERRY NUCLEAR PLANT UNITS 1, 2, AND 3 10 CFR 50.46 ANNUAL REPORT

ENCLOSURE BROWNS FERRY NUCLEAR PLANT, UNIT I 10 CFR 50.46 ANNUAL REPORT Baseline analysis report:

GE Hitachireport 0000-01 15-3713-RO, "BrownsFerry Nuclear Plant Unit 1 Supplementary Report of ECCS-LOCA Additional Single Failure Evaluation at Current Licensed Thermal Power (CL TP)," March 2010.

The Unit 1 core currently contains only the GE14 fuel design.

Description of Changes or Errors There have been no additional changes or errors since the issuance of the baseline analysis in March 2010. The Peak Clad Temperature (PCT) for GE14 fuel remains at the 1920°F value provided in the baseline analysis report.

E-1 of 3

ENCLOSURE BROWNS FERRY NUCLEAR PLANT, UNIT 2 10 CFR 50.46 ANNUAL REPORT Baseline analysis reports:

ANP-2908(P) Revision 0, Browns Ferry Units 1, 2, and 3 105% OLTP LOCA Break Spectrum Analysis, AREVA NP Inc., March 2010.

ANP-2910(P) Revision 0, Browns Ferry Units 1, 2, and 3 105% OLTP LOCA-ECCS Analysis MAPLHGR Limit forATRIUMm-10 Fuel, AREVA NP Inc., March 2010.

The Unit 2 core currently contains only the ATRIUM TM -1 0 fuel design. Report ANP-291 0, Revision 0, contains the baseline PCT value of 1990°F for this fuel type.

Description of Changes or Errors Relative to the Previous Report The Unit 2, Cycle 17, licensing analysis results indicated that one of the lattices in the new fuel batch was more limiting from a PCT standpoint compared to the fuel types in the baseline analysis. The more limiting lattice increased the PCT by 2 0 F.

In September 2010, AREVA notified TVA of a change in the numerical view factors used in the radiative heat transfer model in the HUXY code. This change resulted in a PCT increase of 1IF.

Cumulative Effect of PCT Changes - Unit 2 Baseline PCT 1990°F New limiting lattice from unit 2, cycle 17, licensing analysis 20F Revised HUXY numerical view factor treatment 1°F Accumulated changes since baseline analysis 30F New licensing PCT 1993 0F E-2 of 3

ENCLOSURE BROWNS FERRY NUCLEAR PLANT, UNIT 3 10 CFR 50.46 ANNUAL REPORT Baseline analysis reports:

ANP-2908(P) Revision 0, Browns Ferry Units 1, 2, and 3 105% OL TP LOCA Break Spectrum Analysis, AREVA NP Inc., March 2010.

ANP-2910(P) Revision 0, Browns Ferry Units 1, 2, and 3 105% OLTP LOCA-ECCS Analysis MAPLHGR Limit for A TRIUMT' M-1O Fuel, AREVA NP Inc., March 2010.

The Unit 3 core currently contains only the ATRIUM TM-10 fuel design. Report ANP-2910, Revision 0, contains the baseline PCT value of 1990°F for this fuel type.

Description of Changes or Errors Relative to the Previous Report The Unit 2, Cycle 17, licensing analysis results indicated that one of the lattices in the new fuel batch was more limiting from a PCT standpoint compared to the fuel types in the baseline analysis. The more limiting lattice increased the PCT by 2°F. Since the most limiting lattice in any Browns Ferry unit is used for all the units with AREVA fuel, this change applies to Unit 3 as well.

In September 2010, AREVA notified TVA of a change in the numerical view factors used in the radiative heat transfer model in the HUXY code. This change resulted in a PCT increase of I°F.

Cumulative Effect of PCT Changes - Unit 3 Baseline PCT 1990°F New limiting lattice from unit 2, cycle 17, licensing analysis 20F Revised HUXY numerical view factor treatment 1 °F Increased core spray leakage from lower sectional replacement hardware 190 F modification (reported in the April 30, 2010 10 CFR 50.46 Annual Report)

Accumulated changes since baseline analysis 22 0 F New licensing PCT 2012°F E-3 of 3