ML071130092

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

ML071130092
Person / Time
Site:	South Texas
Issue date:	04/27/2007
From:	Thadani M NRC/NRR/ADRO/DORL/LPLIV
To:	Sheppard J South Texas
Thadani, M C, NRR/DORL/LP4, 415-1476
References
GL-06-002, TAC MD1035, TAC MD1036
Download: ML071130092 (5)

Text

April 27, 2007 Mr. James J. Sheppard President and Chief Executive Officer STP Nuclear Operating Company South Texas Project Electric Generating Station P.O. Box 289 Wadsworth, TX 77483

SUBJECT:

SOUTH TEXAS PROJECT, UNITS 1 AND 2 - RESPONSE TO GENERIC LETTER 2006-02, GRID RELIABILITY AND THE IMPACT ON PLANT RISK AND THE OPERABILITY OF OFFSITE POWER (TAC NOS. MD1035 AND MD1036)

Dear Mr. Sheppard:

On February 1, 2006, the U.S. Nuclear Regulatory Commission (NRC) issued 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.

In GL 2006-02 (GL), the NRC staff notified the licensees of the NRC staffs need for information in four areas as follows:

(1) Use of protocols between the nuclear power plant (NPP) and the transmission system operator (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 in monitoring grid conditions to determine the operability of offsite power systems under plant technical specifications. (The TSO, ISO, or RA/RC is responsible for preserving the reliability 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 the TSOs to assist NPPs in monitoring grid conditions 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 once in 20 site-years, in accordance with RG 1.155.

Subsequent to the GL, the NRC issued a request for additional information (RAI) (ADAMS Accession No. ML063380308) regarding the resolution of GL 2006-02 to 63 of 65 holders of

J. J. Sheppard operating licenses for nuclear power reactors. The RAI requested that licensees respond to questions in 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 March 30, 2006 (ADAMS Accession No. ML060940432), and January 30, 2007 (ADAMS Accession No. ML070360037), you responded to the information request of GL 2006-02 and the subsequent RAI, respectively. Based on the information you provided, the NRC staff has concluded that compliance with the NRC regulatory requirements governing electric power sources and associated personnel training is being maintained. Accordingly, the NRC staff considers your response to GL 2006-02 complete.

If you have any questions, please contact me at 301-415-1476.

Sincerely,

/RA/

Mohan C. Thadani, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499 cc: See next page

ML060940432), and January 30, 2007 (ADAMS Accession No. ML070360037), you responded to the information request of GL 2006-02 and the subsequent RAI, respectively. Based on the information you provided, the NRC staff has concluded that compliance with the NRC regulatory requirements governing electric power sources and associated personnel training is being maintained. Accordingly, the NRC staff considers your response to GL 2006-02 complete.

Sincerely,

/RA/

Mohan C. Thadani, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499 cc: See next page DISTRIBUTION:

PUBLIC RidsNrrPMMThadani LPLIV Reading RidsNrrLALFeizollahi RidsAcrsAcnwMailCenter RidsOgcRp RidsNrrDorlLpl4 RidsRgn4MailCenter JEargle, NRR ACCESSION NO: ML071130092 OFFICE NRR/LPL4/PM NRR/LPL4/PM NRR/LPL4/LA NRR/LPL4/BC NAME MThadani JEargle/MMarkley LFeizollahi THiltz/MMarkley DATE 4/26/07 4/27/07 4/25/07 4/27/07 South Texas Project, Units 1 & 2 cc:

Senior Resident Inspector E. D. Halpin U.S. Nuclear Regulatory Commission Site Vice President P.O. Box 289 STP Nuclear Operating Company Wadsworth, TX 77483 South Texas Project Electric Generating Station C. M. Canady P.O. Box 289 City of Austin Wadsworth, TX 77483 Electric Utility Department 721 Barton Springs Road S. M. Head, Manager, Licensing Austin, TX 78704 STP Nuclear Operating Company P.O. Box 289, Mail Code: N5014 J. J. Nesrsta/R. K. Temple Wadsworth, TX 77483 E. Alercon/Kevin Pollo City Public Service Board C. T. Bowman P.O. Box 1771 General Manager, Oversight San Antonio, TX 78296 STP Nuclear Operating Company P.O Box 389 INPO Wadsworth, TX 77483 Records Center 700 Galleria Parkway Marilyn Kistler Atlanta, GA 30339-3064 Sr. Staff Specialist, Licensing STP Nuclear Operating Company Regional Administrator, Region IV P.O. Box 289, Mail Code 5014 U.S. Nuclear Regulatory Commission Wadsworth, TX 77483 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011 Environmental and Natural Resources Policy Director Steve Winn/Christie Jacobs P.O. Box 12428 Eddy Daniels/Marty Ryan Austin, TX 78711-3189 NRC Energy, Inc.

211 Carnegie Center Jon C. Wood Princeton, NJ 08540 Cox, Smith, & Matthews 112 East Pecan, Suite 1800 Judge, Matagorda County San Antonio, TX 78205 Matagorda County Courthouse 1700 Seventh Street Director Bay City, TX 77414 Division of Compliance & Inspection Bureau of Radiation Control A. H. Gutterman, Esq. Texas Department of State Health Services Morgan, Lewis & Bockius 1100 West 49th Street 1111 Pennsylvania Avenue, NW Austin, TX 78756 Washington, DC 20004 South Texas Project, Units 1 & 2 March 2007

cc:

Mr. Ted Enos Ken Coates 4200 South Hulen Plant General Manager Suite 422 STP Nuclear Operating Company Ft. Worth, TX 76109 South Texas Project Electric Generating Station Brian Almon P.O. Box 289 Public Utility Commission Wadsworth, TX 77483 William B. Travis Building P.O. Box 13326 Mr. Terry Parks, Chief Inspector 1701 North Congress Avenue Texas Department of Licensing Austin, TX 78701-3326 and Regulation Boiler Division Susan M. Jablonski P.O. Box 12157 Office of Permitting, Remediation Austin, TX 78711 and Registration Texas Commission on Environmental Quality MC-122 P.O. Box 13087 Austin, TX 78711-3087 March 2007