ML071170506

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

ML071170506
Person / Time
Site:	Palo Verde
Issue date:	05/03/2007
From:	Fields M NRC/NRR/ADRO/DORL/LPLIV
To:	Edington R Arizona Public Service Co
Markley, M T, NRR/DORL/LP4, 301-415-5723
References
TAC MD1011, TAC MD1012, TAC MD1013
Download: ML071170506 (4)

Text

May 3, 2007 Mr. Randall K. Edington Senior Vice President, Nuclear Mail Station 7602 Arizona Public Service Company P. O. Box 52034 Phoenix, AZ 85072-2034

SUBJECT:

PALO VERDE NUCLEAR GENERATING STATION, UNITS 1, 2, AND 3 -

RESPONSE TO GENERIC LETTER 2006-02, GRID RELIABILITY AND THE IMPACT ON PLANT RISK AND THE OPERABILITY OF OFFSITE POWER (TAC NOS. MD1011, MD1012, AND MD1013)

Dear Mr. Edington:

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 Documents 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, 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

R. K. Edington 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; and (6) Interface With Transmission System Operator During Extended Plant Maintenance.

By letters dated March 29 and July 13, 2006, and January 30, 2007 (ADAMS Accession Nos.

ML060950437, ML062000038, and ML070380271, respectively), you responded to the information request of GL 2006-02 and the subsequent RAI. Based on the information you provided, the 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 Michael T. Markley at 301-415-5723.

Sincerely,

/RA/

Mel B. Fields, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN 50-528, STN 50-529, and STN 50-530 cc: See next page

ML060950437, ML062000038, and ML070380271, respectively), you responded to the information request of GL 2006-02 and the subsequent RAI. Based on the information you provided, the 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 Michael T. Markley at 301-415-5723.

Sincerely,

/RA/

Mel B. Fields, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. STN 50-528, STN 50-529, and STN 50-530 cc: See next page DISTRIBUTION:

PUBLIC RidsNrrDorlLpl4 RidsNrrPMMMarkley LPLIV r/f RidsNrrLAJBurkhardt RidsOgcRp RidsAcrsAcnwMailCenter RidsNrrPMMFields RidsRgn4MailCenter ADAMS Accession No.: ML071170506 OFFICE NRR/LPL4/PM NRR/LPL4/PM NRR/LPL4/LA NRR/LPL4/BC NAME MMarkley MFields JBurkhardt THiltz DATE 4/27/07 5/2/07 5/2/07 5/3/07 Palo Verde Nuclear Generating Station cc:

Mr. Steve Olea Mr. John Taylor Arizona Corporation Commission Public Service Company of New Mexico 1200 W. Washington Street 2401 Aztec NE, MS Z110 Phoenix, AZ 85007 Albuquerque, NM 87107-4224 Mr. Douglas Kent Porter Mr. Geoffrey M. Cook Senior Counsel Southern California Edison Company Southern California Edison Company 5000 Pacific Coast Hwy Bldg N50 Law Department, Generation Resources San Clemente, CA 92672 P.O. Box 800 Rosemead, CA 91770 Mr. Robert Henry Salt River Project Senior Resident Inspector 6504 East Thomas Road U.S. Nuclear Regulatory Commission Scottsdale, AZ 85251 P.O. Box 40 Buckeye, AZ 85326 Mr. Jeffrey T. Weikert Assistant General Counsel Regional Administrator, Region IV El Paso Electric Company U.S. Nuclear Regulatory Commission Mail Location 167 Harris Tower & Pavillion 123 W. Mills 611 Ryan Plaza Drive, Suite 400 El Paso, TX 79901 Arlington, TX 76011-8064 Mr. John Schumann Chairman Los Angeles Department of Water & Power Maricopa County Board of Supervisors Southern California Public Power Authority 301 W. Jefferson, 10th Floor P.O. Box 51111, Room 1255-C Phoenix, AZ 85003 Los Angeles, CA 90051-0100 Mr. Aubrey V. Godwin, Director Mr. Brian Almon Arizona Radiation Regulatory Agency Public Utility Commission 4814 South 40 Street William B. Travis Building Phoenix, AZ 85040 P.O. Box 13326 1701 North Congress Avenue Mr. Scott Bauer, Acting General Manager Austin, TX 78701-3326 Regulatory Affairs and Performance Improvement Ms. Karen O'Regan Palo Verde Nuclear Generating Station Environmental Program Manager Mail Station 7636 City of Phoenix P.O. Box 52034 Office of Environmental Programs Phoenix, AZ 85072-2034 200 West Washington Street Phoenix AZ 85003 Mr. Matthew Benac Assistant Vice President Nuclear & Generation Services El Paso Electric Company 340 East Palm Lane, Suite 310 Phoenix, AZ 85004 January 2007