ML082340968

July 2008 Evidentiary Hearing - Intervenor Exhibit NEC-JH_22, NRC Staff Memorandum: Summary of Meeting Held on January 8, 2008 Between the U.S. Nuclear Regulatory Commission Staff and Entergy Nuclear Operation, Inc..

ML082340968
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	01/31/2008
From:	Rowley J Division of License Renewal
To:	NRC/SECY/RAS
SECY RAS
References
06-849-03-LR, 50-271-LR, Entergy-Intervenor-NEC-JH_22, RAS M-194
Download: ML082340968 (9)

Text

NEC-JH_22 LICENSEE:

Entergy Nuclear Operations, Inc.

FACILITY:

Vermont Yankee.,Nuclear Power Station

SUMMARY

OF MEETING HELD ON JANUARY 8,..2008, BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION STAFF AND ENTERGY NUCLEAR OPERATIONS,: INC. REPRESENTATIVES.TO.DISCUSS THE RESPONSE TO A.REQUEST FOR ADDITIONAL INFORMATION PERTAINING TO THE VERMONT YANKEE NUCLEAR POWER STATION LICENSE RENEWAL APPLICATION On January 8, 2008, the Nuclear Regulatory Commission staff (the staff) met with members of Entergy Nuclear Operations, Inc. (the applicant) in a public meeting to discuss the response to a request for additional information.(RAI).made by the staff pertaining to the Vermont Yankee Nuclear Power Station (VYNPS) license renewal application. The applicant had an opportunity to comment on. this summary.

A list of attendees is provided in Enclosure 1. The meeting agenda is provided in Enclosure 2.

Comments made by the public during the meeting are provided in Enclosure 3. A copy of the slides presented by the applicant is provided as Enclosure 4. A summary of the discussion.

follows:

Background

In a letter dated November 27, 2007, the staff issued RAI 4.3.3-2 to the applicant. The purpose.of the request was to gather additional information on the calculations used at VYNPS to reanalyze their time-limited aging analysis (TLAA) that addresses environmentally-assisted fatigue. In a letter dated December 11, 2007, the applicant

-provided its response to RAI 4.3.3-2 to the staff. The staff reviewed the response and further questioned the methodology described in the submittal and statements made that shearstresses are negligible during a conference call with the applicant on December 18, 2007. During the call, the applicant requested a face-to-face meeting to ensurethat its position pertaining to this highly technical issue was properly and effectively communicated.

Discussion During the meeting, the applicant made a slide presentation of the reactor vessel nozzle environmental fatigue analyses for license renewal at VYNPS. The applicant reviewed the terminology used in the response to RAI 4.3.3-2. The applicant reviewed the analyzed vessel nozzle configurations to identify where the shear stresses in the nozzles were negligible, where they were not, and the effects on the fatigue analysis at the locations where shear stresses were not negligible.

DOCKETED I I*vI*/'uI i'i

,-en II, USNRC Doce No. 50 -a0 Od alExhibit No.MV-,!-2 August 12, 2008 (11:00am) 0 Apican OFFICE OF SECRETARY i"f' RULEMAKINGS AND NRC Stff ADJUDICATIONS STAFF NEC072277 IDETF)

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The applicant explained that nozzle corner, blend radius, and inner radius are interchangeable terms for locations with geometrical discontinuities; that is, locations where stresses are maximum. The applicant explained that the methodology employed incorporates the use of axisymmetric modeling rather than an exact configuration 3-Dimensional (3-D) or 2-Dimensional (2-D) modeling. They explained that axisymmetric modeling is a 3-D model except that it models the nozzle/vessel interface as a sphere with a multiplier to account for pressure stress effects, rather than a pipe joined to a cylinder. With the aid of colored graphs, the applicant demonstrated specific nozzles where shear stresses are negligible. The applicant also discussed the various conservatisms used in their analysis.

Conclusion

1. Based on the analyses performed, the applicant presented its conclusion that the effects of shear stresses were negligible or were separately addressed for all nozzles analyzed.

2. Based on its interaction with the NRR staff during the meeting, the applicant agreed to perform additional confirmatory work and submit results to the staff for review and acceptance. This work effort will include:

1) Performing benchmarking calculations on the feedwater nozzle, which is the most limiting component, using the axisymmetric finite element model, taking fully into account all stress components on the nozzle and using the ANSYS FEM computer code to model all defined transients;

2) Demonstrating that the Vermont Yankee specific benchmarking calculations bound the results for the Core Spray and Recirculation outlet nozzles.

3) Calculating fatigue usage factors (CUFs) using NRC approved ASME Section III NB-3200 methods; and

4) Comparing the resulting CUFs to the previous environmental assisted fatigue calculations to establish whether the previous calculations are adequate.

Jonathan G. Rowley, Project Manager Projects Branch 2 Division of License Renewal Office of Nuclear Reactor Regulation Docket No. 50-271 NEC072278

Enclosures:

1. Attendance List

2. Agenda

3. Public Comments

4. Presentation slides ccw/encls: See next page I

.I NEC072279

DOCUMENT NAME: G:\\ADRO\\DLR\\RLRB\\ROWLEY\\Meeting with VY-Entergy Summary - January 8, 2008.doc OFFICE LA:DLR PM:RPB2:DLR BC:RPB2:DLR BC:RERI:DLR NAME JRowley RFranovich KChang DATE

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MEETING BETWEEN THE NRC STAFF AND ENTERGY NUCLEAR OPERATIONS, INC.

VERMONT YANKEE NUCLEAR POWER STATION LICENSE RENEWAL APPLICATION 6003 EXECUTIVE BOULEVARD ROOM EBB1B15 ROCKVILLE, MARYLAND MEETING ATTENDANCE LIST JANUARY 8, 2008 PARTICIPANTS Jonathan Rowley Samson Lee John Fair Kenneth Chang PT Kuo Rani Franovich Robert Sun Qi Gan Kaihwa Hsu Ricardo Rodriguez Mary Baty Perry Buckberg Evelyn Gettys Yeon-Ki Chung Peter Wen On Yee Gary Hammer David Mannai John McCann Jay Thayer Matias Travieso-Diaz Michael Metell Garry Young Norm Rademacher AFFILIATIONS U.S. Nuclear Regulatory Commission (NRC)

NRC NRC NRC NRC NRC NRC NRC NRC NRC NRC NRC NRC NRC NRC NRC NRC Entergy Nuclear Operations, Inc. (Entergy)

Entergy Entergy Entergy Entergy Entergy Entergy

.1 I

NEC072281

Alan Cox Entergy PARTICIPANTS James Fitzpatrick Scott Goodwin John Dreyfuss Gary L. Stevens Terry. J. Herrmann Joe Hopenfeld David Lochbaum THE FOLLOWING PARTICAPATED Sarah Hoffman John Sipos Paul Eddy Joan Leary Matthews Blaise Constantakes Rudolf Hausler Raymond Shadis Claire Chang Ulrich Witte Ed Anthes Rich Schaller Chalmer Myer Bob Audette Susan Smallheer Sally Shaw Fred Mogolesko AFFILIATIONS Entergy Entergy Entergy Structural Integrity Associates Structural Integrity Associates New England Coalition (NEC)

Union of concerned Scientist VIA TELEPHONE BRIDGELINE Vermont Department of Public Service New York Office of the Attorney General New York Office of the Attorney General New York Office of the Attorney General New York Office of the Attorney General New York Office of the Attorney General NEC NEC NEC Nuclear Free Vermont Strategic Teaming and Resource Sharing Southern Nuclear Operating Company The Brattleboro Reformer The Rutland Herald Entergy MEETING BETWEEN THE NRC STAFF AND ENTERGY NUCLEAR OPERATIONS, INC.

VERMONT YANKEE NUCLEAR POWER STATION LICENSE RENEWAL APPLICATION 6003 EXECUTIVE BOULEVARD ROOM EBB1B15 ROCKVILLE, MARYLAND AGENDA NEC072282

JANUARY 8, 2008 IV.

Introduction and opening remarks Discussion of Response to Request for Additional Information (Response to RAI 4.3.3-2)

Public Comments Adjourn 10 minutes 80 minutes 30 minutes NEC072283

MEETING BETWEEN THE NRC STAFF AND.ENTERGY NUCLEAR OPERATIONS, INC.

VERMONT YANKEE NUCLEAR POWER STATION LICENSE RENEWAL APPLICATION ROCKVILLE, MARYLAND ROOM EBB1B15 MEETING MINUTES JANUARY 8, 2008 In a letter dated November 27, 2007, the staff issued RAI 4.3.3-2 to the applicant. The purpose of the request was to gather additional information on the calculations used at VYNPS to reanalyze their time-limited aging analysis (TLAA) that addresses environmentally-assisted fatigue. In a letter dated December 11, 2007, the applicant provided its response to RAI 4.3.3-2 to the staff. The staff reviewed the response and further questioned the methodology described in the submittal and statements made that shear stresses are negligible during a conference call with the applicant on December 18, 2007. During the call, the applicant requested a face-to-face meeting to ensure that its position pertaining to this highly technical issue was properly and effectively communicated.

Discussion During the meeting, the applicant made a slide presentation of the reactor vessel nozzle environmental fatigue analyses for license renewal at VYNPS. The applicant reviewed the terminology used in the response to RAI 4.3.3-2. The applicant reviewed the analyzed vessel nozzle configurations to identify where the shear stresses in the nozzles were negligible, where they were not, and the effects on the fatigue analysis at the locations where shear stresses were not negligible.

The applicant explained that nozzle corner, blend radius, and inner radius are interchangeable terms for locations with geometrical discontinuities; that is, locations where stresses are a maximum. The applicant explained that their methodology incorporates the use of axisymmetric modeling rather than an exact configuration 3-Dimensional (3-D) or 2-Dimensional (2-D) modeling. They explained that axisymmetric modeling is a 3-D model except that it models the nozzle/vessel interface as a sphere with a multiplier to account for pressure stress effects, rather than a pipe joined to a cylinder. With the aid of colored graphs, the applicant demonstrated specific nozzles where shear stresses are negligible. The applicant also discussed the various conservatisms used in their analysis.

Conclusion

1. Based on the analyses performed, the applicant presented its conclusion that the effects of shear stresses were negligible or were selparately addressed for all nozzles analyzed.

NEC072284

2. Based on its interaction with the NRR staff during the meeting, the applicant agreed to perform additional confirmatory work and submit results to the staff for review and acceptance. This work effort will include:

1) Performing benchmarking calculations on the feedwater nozzle, which is the most limiting component, using the axisymmetric finite element model, taking fully into account all stress components on the nozzle and using the ANSYS FEM computer code to model all defined transients;

2) Demonstrating that the Vermont Yankee specific benchmarking calculations bound the results for the core spray and recirculation outlet nozzles.

3) Calculating fatigue usage factors (CUFs) using NRC approved ASME Section III NB-3200 methods; and

4) Comparing the resulting CUFs to the previous environmental assisted fatigue calculations to establish whether the previous calculations are adequate i

I NEC072285