ML071080225

Response to Generic Letter 2006-02 Grid Reliability and the Impact on Plant Risk and the Operability of Offsite Power

ML071080225
Person / Time
Site:	Watts Bar
Issue date:	05/03/2007
From:	Moroney B NRC/NRR/ADRO/DORL/LPLII-2
To:	Swafford P Tennessee Valley Authority
Moroney B, NRR/DORL, 415-3974
References
GL-06-002, RG-1.155, TAC MD1049
Download: ML071080225 (4)

Text

May 3, 2007Mr. Preston D. SwaffordInterim Chief Nuclear Officer Nuclear Support Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801

SUBJECT:

WATTS BAR NUCLEAR PLANT, UNIT 1 - RESPONSE TO GENERIC LETTER2006-02 "GRID RELIABILITY AND THE IMPACT ON PLANT RISK AND THE OPERABILITY OF OFFSITE POWER" (TAC NO. MD1049)

Dear Mr. Swafford:

On February 1, 2006, the U.S. Nuclear Regulatory Commission (NRC) issued Generic Letter(GL) 2006-02, "Grid Reliability and the Impact on Plant Risk and the Operability of Offsite Power" (Agencywide Document Access and Management System (ADAMS) Accession No. ML060180352) to all holders of operating licenses for nuclear power reactors except those who have permanently ceased operation and have certified that fuel has been removed from the reactor vessel.GL 2006-02 notified licensees of the NRC staff's need for information in four areas, as follows:

(1) use of protocols between the nuclear power plant (NPP) and the transmission systemoperator (TSO), independent system operator (ISO), or reliability coordinator/authority (RC/RA) and the use of transmission load flow analysis tools (analysis tools) by TSOs to assist NPPs inmonitoring grid conditions to determine the operability of offsite power systems under plant technical specifications (TSs). (The TSO, ISO, or RA/RC is responsible for preserving thereliability of the local transmission system. In this GL the term TSO is used to denote these entities);(2) use of NPP/TSO protocols and analysis tools by TSOs to assist NPPs in monitoring gridconditions for consideration in maintenance risk assessments;(3) offsite power restoration procedures in accordance with Section 2 of NRC Regulatory Guide(RG) 1.155, "Station Blackout;" and(4) losses of offsite power caused by grid failures at a frequency equal to or greater than oncein 20 site-years in accordance with RG 1.155.Subsequent to the GL, the NRC issued a Request For Additional Information (RAI) (ADAMSAccession No. ML063380308) regarding the resolution of GL 2006-02 to 63 of 65 holders of P. Swafford-2-operating licenses for nuclear power reactors. The RAI requested licensees respond to questionsin the following areas:(1) Switchyard Minimum Voltage;(2) Loss of Real-Time Contingency Analysis (RTCA) Capability; (3) Verification of RTCA Predicted Post-Trip Voltage; (4) Identification of Applicable Single Contingencies; (5) Seasonal Variation in Grid Stress (reliability and Loss-of-offsite power (LOOP) Probability; (6) Interface With Transmission System Operator During Extended Plant Maintenance.By letters dated April 3, 2006 (ADAMS Accession No. ML060950306), and January 31, 2007(ADAMS Accession No. ML070330051), the Tennessee Valley Authority (TVA) responded to the information request of GL 2006-02 and the subsequent RAI, respectively. Based on the information provided, the staff has concluded that compliance is being maintained with NRC regulatory requirements governing electric power sources and associated personnel training and considers TVA's response to GL 2006-02 complete for the Watts Bar Nuclear Plant, Unit 1.If you have any questions, please contact me 301-415-3974.Sincerely,/RA/Brendan T. Moroney, Project ManagerPlant Licensing Branch II-2 Division of Operating Licensing Office of Nuclear Reactor RegulationDocket Nos. 50-390 cc: See next page

ML060950306), and January 31, 2007(ADAMS Accession No. ML070330051), the Tennessee Valley Authority (TVA) responded to the information request of GL 2006-02 and the subsequent RAI, respectively. Based on the information provided, the staff has concluded that compliance is being maintained with NRC regulatory requirements governing electric power sources and associated personnel training and considers TVA's response to GL 2006-02 complete for the Watts Bar Nuclear Plant, Unit 1.If you have any questions, please contact me 301-415-3974.Sincerely,/RA/Brendan T. Moroney, Project ManagerPlant Licensing Branch II-2 Division of Operating Licensing Office of Nuclear Reactor RegulationDocket Nos. 50-390 cc: See next pageDistribution

PUBLICLPL2-2 r/fRidsNrrLACSolaRidsNrrPMBMoroney RidsNrrDorlLpl2-2RidsOgcRpRidsAcrsAcnwMailCenterRidsRgn2MailCenter RidsNrrDeEeebSCampbell, EDO, Region IIJRobinson, NRRADAMS ACCESSION NUMBER: ML071080225OFFICELPL2-2/PMLPL2-2/LA EEEB/BCLPL2-2/BCNAMEBMoroneyRSolaGWilsonTBoyceDATE4/19/074/19/074/25/07 5/3/07 Mr. Preston D. SwaffordTennessee Valley AuthorityWATTS BAR NUCLEAR PLANT cc:Mr. Ashok S. Bhatnagar, Senior Vice President Nuclear Operations Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801Mr. Larry S. Bryant, Vice PresidentNuclear Engineering & Technical Services Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801Mr. Michael D. Skaggs, Site Vice PresidentWatts Bar Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Spring City, TN 37381General CounselTennessee Valley Authority 6A West Tower 400 West Summit Hill Drive Knoxville, TN 37902Mr. John C. Fornicola, ManagerNuclear Assurance Tennessee Valley Authority 6A Lookout Place 1101 Market Street Chattanooga, TN 37402-2801Mr. Robert H. Bryan, Jr., General ManagerLicensing and Industry Affairs Tennessee Valley Authority 4X Blue Ridge 1101 Market Street Chattanooga, TN 37402-2801Ms. Beth A. Wetzel, ManagerCorporate Nuclear Licensing and Industry Affairs Tennessee Valley Authority 4X Blue Ridge 1101 Market Street Chattanooga, TN 37402-2801Mr. James D. Smith, Acting ManagerLicensing and Industry Affairs Watts Bar Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Spring City, TN 37381Mr. Michael J. Lorek, Plant ManagerWatts Bar Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Spring City, TN 37381Senior Resident InspectorWatts Bar Nuclear Plant U.S. Nuclear Regulatory Commission 1260 Nuclear Plant Road Spring City, TN 37381County Executive375 Church Street Suite 215 Dayton, TN 37321County Mayor P. O. Box 156 Decatur, TN 37322Mr. Lawrence E. Nanney, DirectorDivision of Radiological Health Dept. of Environment & Conservation Third Floor, L and C Annex 401 Church Street Nashville, TN 37243-1532Ms. Ann P. Harris341 Swing Loop Road Rockwood, TN 37854