ML063390052

RAI, Concerning Fire Protection Three-Unit Operation Amendment and Exemption Request (TAC Nos. MD3412, MD3413, MD3414, MD3597 and MD3598) (TS-459)

ML063390052
Person / Time
Site:	Browns Ferry
Issue date:	12/05/2006
From:	Ellen Brown NRC/NRR/ADRO/DORL/LPLII-2
To:	Singer K Tennessee Valley Authority
Brown Eva, NRR/DORL, 415-2315
References
TAC MD3412, TAC MD3413, TAC MD3414, TAC MD3596, TAC MD3597, TAC MD3598
Download: ML063390052 (6)

Text

December 5, 2006 Mr. Karl W. Singer Chief Nuclear Officer and Executive Vice President Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801

SUBJECT:

BROWNS FERRY NUCLEAR PLANT, UNITS 1, 2, AND 3 REQUEST FOR ADDITIONAL INFORMATION CONCERNING FIRE PROTECTION THREE-UNIT OPERATION AMENDMENT AND EXEMPTION REQUEST (TAC NOS. MD3412, MD3413, MD3414, MD3596, MD3597, AND MD3598)(TS-459)

Dear Mr. Singer:

By letters dated October 26 and November 16, 2006, the Tennessee Valley Authority (the licensee) submitted an exemption and an amendment request for Browns Ferry Nuclear Plant, Units 1, 2, and 3.

The proposed amendment requests revisions to the Fire Protection License Conditions for Units 1, 2, and 3, condition numbers (13), (14), and (7), respectively, to accommodate safe operation. The proposed exemption requests an allowance to permit intervening combustibles in the 20-foot separation zone for certain specified fire areas in the 480V Reactor Building Vent Boards 1B, 2B, and 3B; small panels in Units 1, 2, and 3; and the 1-hour fire rated fire wrap (Thermo-Lag) material in the 20-foot separation zones. The enclosed Request for Additional Information (RAI) is related to these submittals.

A response to the enclosed RAI is needed before the Nuclear Regulatory Commission staff can complete the review.

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

Sincerely,

/RA/

Eva A. Brown, 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:

RAI cc w/enclosure: See next page

ML063390052 NRR-088 OFFICE LPL2-2/PM LPL2-2/PM LPL2-2/LA DRA/AFPB LPL3-1/BC NAME EBrown MChernoff BClayton SWeerakody LRaghavan DATE 12/5/06 12/5/06 12/5/06 12/6/06 12/5/06

SUBJECT:

BROWNS FERRY NUCLEAR PLANT, UNITS 1, 2, AND 3 REQUEST FOR ADDITIONAL INFORMATION CONCERNING FIRE PROTECTION THREE-UNIT OPERATION AMENDMENT AND EXEMPTION REQUEST (TAC NOS. MD3412, MD3413, MD3414, MD3596, MD3597, AND MD3598)

(TS-459)

Date: December 5, 2006 DISTRIBUTION:

PUBLIC LPL2-2 R/F RidsNrrDorlLpl2-2 RidsNrrLACGoldstein RidsNrrPMMChernoff RidsNrrPMEBrown RidsAcrsAcnwMailCenter RidsOgcRp RidsRgn2MailCenter (GMacDonald, GWiseman, CPayne)

RidsNrrDorlDpr RidsNrrLABClayton (Hard Copy)

RidsNrrLACGoldstein (Hard Copy)

RidsNrrDorlDnrl RidsNrrDraAfpb (SWeerakody)

RidsNrrDra (CHolden)

NIqbal PQualls LRegner JBoska

REQUEST FOR ADDITIONAL INFORMATION FIRE PROTECTION THREE-UNIT OPERATION AMENDMENT AND EXEMPTION REQUEST TENNESSEE VALLEY AUTHORITY BROWNS FERRY NUCLEAR PLANT, UNITS 1, 2 AND 3 DOCKET NOS. 50-259, 50-260, 50-296 Title 10 to the Code of Federal Regulations (10 CFR) Part 50, Appendix R,Section III.G.2 states:

Except as provided for in paragraph G.3 of this section, where cables or equipment, including associated non-safety circuits that could prevent operation or cause maloperation due to hot shorts, open circuits, or shorts to ground, of redundant trains of systems necessary to achieve and maintain hot shutdown conditions are located within the same fire area outside of primary containment, one of the following means of ensuring that one of the redundant trains is free of fire damage shall be provided.

Section III.G.2.b states:

Separation of cables and equipment and associated non-safety circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustible or fire hazards. In addition, fire detectors and an automatic fire suppression system shall be installed in the fire area.

In the fire zones referenced in the exemption request, the licensee chose to comply with Section III.G.2.b to provide assurance of maintaining one train free of fire damage. The following information is required to ensure that one train is maintained free of fire damage due to the presence of intervening combustible material (Thermolag) in the 20-foot separation zone.

1. The presence of transient combustible material in the 20-foot separation zone could be ignited by a fire in the ventilation cabinets and contribute to fire severity beyond that analyzed by the licensee. This could result in a fire starting in the cabinet propagating beyond the 20-foot zone. Address the measures put in place to ensure that the staging and storing of transient combustible material will not occur in the 20-foot separation zone.

2. The analysis, provided by the licensee, shows that a ventilation cabinet fire would not result in fire damage affecting the safe shutdown capability. In their discussion, the licensee used fire effects of a single bundle cabinet fire from NUREG/CR-6850, EPRI/NRC-RES Fire PRA Methodology for Nuclear Power Facilities. This does not

appear to be the limiting fire in the NUREG for a cabinet fire of this type. Address why NUREG/CR 6850 single bundle cabinet fire is being used as the basis for the fire evaluation. This discussion should address how this assumption bounds the worst case fire.

For the license amendment request.

1. The Browns Ferry post-fire safe-shutdown analysis assumes a slowly developing fire such that only one actuation would occur at a time, with time between interactions to mitigate the effects of the previous interaction. On page E1-7 of the amendment request, it is stated:

Resolution of . . . multiple spurious hot shorts is being tracked to resolution resolved through the TVA [Tennessee Valley authority]

Corrective Action Program. TVA will monitor and implement resolution when NRC guidance is issued.

TVA is requested to provide information on the actions taken to identify, assess, and correct those circuit failure modes (hot shorts, open circuits, etc.) postulated in the post-fire safe shutdown analysis as a result of a fire that is risk significant.

Mr. Karl W. Singer BROWNS FERRY NUCLEAR PLANT Tennessee Valley Authority cc:

Mr. Ashok S. Bhatnagar, Senior Vice President Mr. Robert G. Jones, General Manager Nuclear Operations Browns Ferry Site Operations Tennessee Valley Authority Browns Ferry Nuclear Plant 6A Lookout Place Tennessee Valley Authority 1101 Market Street P.O. Box 2000 Chattanooga, TN 37402-2801 Decatur, AL 35609 Mr. Larry S. Bryant, Vice President Mr. Larry S. Mellen Nuclear Engineering & Technical Services Browns Ferry Unit 1 Project Engineer Tennessee Valley Authority Division of Reactor Projects, Branch 6 6A Lookout Place U.S. Nuclear Regulatory Commission 1101 Market Street 61 Forsyth Street, SW.

Chattanooga, TN 37402-2801 Suite 23T85 Atlanta, GA 30303-8931 Brian OGrady, Site Vice President Browns Ferry Nuclear Plant Ms. Beth A. Wetzel, Manager Tennessee Valley Authority Corporate Nuclear Licensing P.O. Box 2000 and Industry Affairs Decatur, AL 35609 Tennessee Valley Authority 4X Blue Ridge Mr. Preston D. Swafford, Senior Vice President 1101 Market Street Nuclear Support Chattanooga, TN 37402-2801 Tennessee Valley Authority 6A Lookout Place Mr. William D. Crouch, Manager 1101 Market Street Licensing and Industry Affairs Chattanooga, TN 37402-2801 Browns Ferry Nuclear Plant Tennessee Valley Authority General Counsel P.O. Box 2000 Tennessee Valley Authority Decatur, AL 35609 ET 11A 400 West Summit Hill Drive Senior Resident Inspector Knoxville, TN 37902 U.S. Nuclear Regulatory Commission Browns Ferry Nuclear Plant Mr. John C. Fornicola, General Manager 10833 Shaw Road Nuclear Assurance Athens, AL 35611-6970 Tennessee Valley Authority 6A Lookout Place State Health Officer 1101 Market Street Alabama Dept. of Public Health Chattanooga, TN 37402-2801 RSA Tower - Administration Suite 1552 Mr. Bruce Aukland, Plant Manager P.O. Box 303017 Browns Ferry Nuclear Plant Montgomery, AL 36130-3017 Tennessee Valley Authority P.O. Box 2000 Chairman Decatur, AL 35609 Limestone County Commission 310 West Washington Street Mr. Masoud Bajestani, Vice President Athens, AL 35611 Browns Ferry Unit 1 Restart Browns Ferry Nuclear Plant Mr. Robert H. Bryan, Jr., General Manager Tennessee Valley Authority Licensing and Industry Affairs P.O. Box 2000 Tennessee Valley Authority Decatur, AL 35609 4X Blue Ridge 1101 Market Street Chattanooga, TN 37402-2801