ML063390052
| 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 Nuclear Operations Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. Larry S. Bryant, Vice President Nuclear Engineering & Technical Services Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Brian OGrady, Site Vice President Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609 Mr. Preston D. Swafford, Senior Vice President Nuclear Support Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 General Counsel Tennessee Valley Authority ET 11A 400 West Summit Hill Drive Knoxville, TN 37902 Mr. John C. Fornicola, General Manager Nuclear Assurance Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801 Mr. Bruce Aukland, Plant Manager Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609 Mr. Masoud Bajestani, Vice President Browns Ferry Unit 1 Restart Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609 Mr. Robert G. Jones, General Manager Browns Ferry Site Operations Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609 Mr. Larry S. Mellen Browns Ferry Unit 1 Project Engineer Division of Reactor Projects, Branch 6 U.S. Nuclear Regulatory Commission 61 Forsyth Street, SW.
Suite 23T85 Atlanta, GA 30303-8931 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. William D. Crouch, Manager Licensing and Industry Affairs Browns Ferry Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Decatur, AL 35609 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. Robert H. Bryan, Jr., General Manager Licensing and Industry Affairs Tennessee Valley Authority 4X Blue Ridge 1101 Market Street Chattanooga, TN 37402-2801