ML081360291

Summary of April 17, 2008, Meeting Regarding Steam Dryer Portion of the Extended Power Uprate Review

ML081360291
Person / Time
Site:	Browns Ferry
Issue date:	05/22/2008
From:	Ellen Brown NRC/NRR/ADRO/DORL/LPLII-2
To:
Brown Eva, NRR/DORL, 415-2315
Shared Package
ML081420138	List: ML081120502 ML081130231 ML081360291
References
TAC MD5262, TAC MD5263, TAC MD5264
Download: ML081360291 (4)

Text

May 22, 2008 LICENSEE:

Tennessee Valley Authority (TVA)

FACILITIES: Browns Ferry Nuclear Plant (BFN) Units 1, 2, and 3

SUMMARY

OF APRIL 17, 2008, MEETING WITH TVA REGARDING THE STEAM DRYER PORTION OF THE EXTENDED POWER UPRATE REVIEW (TAC NOS. MD5262, MD5263, AND MD5264)

On April 17, 2008, the U.S. Nuclear Regulatory Commission (NRC) staff conducted a Category 1 public meeting with TVA (the licensee) at NRC Headquarters, One White Flint North, 11555 Rockville Pike, Rockville, Maryland. The purpose of the meeting was for TVA to provide an overview of the proposed modifications and analyses needed to meet the steam dryer stress ratio acceptance criteria. Due to the proprietary nature of the information being discussed, only small portions of the meeting were open to the public. The enclosure contains a list of attendees. The licensee presented slides regarding the steam dryer portion of the extended power uprate (EPU). A non-proprietary version of the slides may be accessed from the NRC Agencywide Documents Access and Management System, No. ML081130231.

DISCUSSION On March 20, 2008, the NRC staff met with TVA to discuss the results of the BFN steam dryer analysis. Based on the stress analysis provided in a March 6, 2008, letter, the meeting focused on the results, which indicated that the minimum alternating stress ratio for the Unit 1 dryer is 1.56 at current licensed thermal power, which, is ~1.18 at EPU conditions. The NRC staff discussed that the stress margin needed for reasonable assurance should be around 2.0 at EPU conditions, which is in line with the margins obtained by previous boiling-water reactor licensees requesting similar power uprates.

The April 17,, 2008, meeting focused on the licensees modifications and analyses proposed to achieve an acceptable stress ratio margin. The licensee went through a summary of the limiting locations identified for the Unit 1 dryer. The listing was done by stress ranking and was grouped into a family according to the location on the dryer. This grouping was useful in that certain solutions addressed any concerns in the affected family. The licensee intends to address the issue with some of the families by modifications along the lines of those installed on another plant. The acoustic vibration suppressor modification was already planned and has been installed in Unit 3. It was confirmed that the results of this modification should be provided to the NRC staff by June 16, 2008. Another modification is planned to further alter the acoustic signature of the main steam system. The licensee stated that, if needed, this modification may be installed during the fall 2008 Unit 1 refueling outage.

The licensee proposed to address the issues with other families with a refining of the information associated with the geometry of certain welds that may allow for the removal of certain conservatisms. The NRC staff indicated concerns with the fidelity of the models proposed being used with the actual condition of the dryer welds. TVA discussed that the refinement of the analysis and acknowledged the need to validate the approach if the refinement results in deviation from empirically derived-factors.

Additional discussions were held regarding the dampening credit associated with a certain phenomenon. A discussion was held regarding additional testing proposed to validate certain assumptions that should better support the crediting of this phenomenon. The licensee also discussed the methodology used to remove noise from the models. The NRC staff continued questioning from the March 20 meeting regarding whether the approach proposed yields realistic results. It was proposed that the licensee take a look at the noise present at different power levels during the Unit 3 power ascension. This approach would be used to validate the baseline selected for subtracting out actual noise.

No members of the public were in attendance and no feedback forms were received. No commitments or regulatory decisions were made by the NRC staff during the meeting.

/RA/

Eva A. Brown, Senior Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-259, 50-260, and 50-296

Enclosure:

List of Attendees cc w/enclosure: See next page

Meeting Summary ML081360291 Pkg.: ML081420138 Public Slides ML081130231 Non-Public Slides ML081120503 CDI Letter ML081120502 NRC-001

List of Attendees U. S. Nuclear Regulatory Commission Public Meeting with Tennessee Valley Authority Steam Dryer Portion of the Browns Ferry Power Uprate April 17, 2008 U. S. NUCLEAR REGULATORY COMMISSION ARGONNE NATIONAL LABORATORY Thomas Boyce Vik Shah Kamal Manoly Chakrapani Basavaraju Mark Hartzman PENN STATE UNIVERSITY Eva Brown Steve Hambric Catherine Haney Patrick Hiland Kamal Manoly Timothy McGinty Zena Abdullahi TENNESSEE VALLEY AUTHORITY McMASTER UNIVERSITY Robert Marks Samir Ziada Kenneth Spates James Emens J.D. Wolcott Denzel Housley STRUCTURAL INTEGRITY Larry Nicholson Marcos Herrera Beth Wetzel Mike Purcell James E. Emens, Jr.

CONTINUUM DYNAMICS INCORPORATED Alan Bilanin Alex Boschitsch

Page 1 of 2 Tennessee Valley Authority BROWNS FERRY NUCLEAR PLANT cc:

Mr. Ashok S. Bhatnagar Senior Vice President Nuclear Generation Development and Construction Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Vice President Nuclear Support Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. H. Rick Rogers Vice President Nuclear Engineering & Technical Services Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. D. Tony Langley, Manager Licensing and Industry Affairs Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609 General Counsel Tennessee Valley Authority 6A West Tower 400 West Summit Hill Drive Knoxville, TN 37902 Mr. John C. Fornicola, General Manager Nuclear Assurance Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. R. G. (Rusty) West Site Vice President Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609 Ms. Beth A. Wetzel, Manager Corporate Nuclear Licensing and Industry Affairs Tennessee Valley Authority 4X Blue Ridge 1101 Market Street Chattanooga, TN 37402-2801 Mr. James E. Emens, Jr.

Supervisor, Nuclear Site Licensing Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609 James B. Baptist Browns Ferry Senior Project Engineer Division of Reactor Projects, Branch 6 U.S. Nuclear Regulatory Commission 61 Forsyth Street, SW.

Suite 24T85 Atlanta, GA 30303-8931 Tomy A. Nazario Browns Ferry Project Engineer Division of Reactor Projects, Branch 6 U.S. Nuclear Regulatory Commission 61 Forsyth Street, SW.

Suite 24T85 Atlanta, GA 30303-8931 Senior Resident Inspector U.S. Nuclear Regulatory Commission Browns Ferry Nuclear Plant 10833 Shaw Road Athens, AL 35611-6970

State Health Officer Alabama Dept. of Public Health RSA Tower - Administration Suite 1552 P.O. Box 303017 Montgomery, AL 36130-3017 Chairman Limestone County Commission 310 West Washington Street Athens, AL 35611 Mr. Larry E. Nicholson, General Manager Performance Improvement Tennessee Valley Authority 3R Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. Michael A. Purcell Senior Licensing Manager Nuclear Power Group Tennessee Valley Authority 4X Blue Ridge 1101 Market Street Chattanooga, TN 37402-2801 Mr. William R. Campbell, Jr.

Chief Nuclear Officer and Executive Vice President 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Page 2 of 2