ML060760279

RAI, Revised Station Blackout Evaluation

ML060760279
Person / Time
Site:	Palo Verde
Issue date:	03/21/2006
From:	Fields M Plant Licensing Branch III-2
To:	James M. Levine Arizona Public Service Co
Fields M , NRR/DORL,415-3062
References
TAC MC8787, TAC MC8788, TAC MC8789
Download: ML060760279 (6)

Text

March 21, 2006 Mr. James M. Levine Executive Vice President, Generation 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 -

REQUEST FOR ADDITIONAL INFORMATION REGARDING THE REVISED STATION BLACKOUT EVALUATION (TAC NOS. MC8787, MC8788, AND MC8789)

Dear Mr. Levine:

By letter dated October 28, 2005, Arizona Public Service submitted a revised Station Blackout evaluation for the Palo Verde Nuclear Generating Station Units 1, 2, and 3, increasing the coping duration from 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> to gain margin relative to nuclear safety.

The Nuclear Regulatory Commission (NRC) staff has reviewed the information provided and determined that additional information is required in order to complete the evaluation. The additional information being requested is enclosed. As discussed with Glenn Michael of your staff, the NRC staff is requesting a response within 30 days of the date of this letter.

If you have any questions, please contact me at 301-415-3062.

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, 50-529 and STN 50-530

Enclosure:

Request for Additional Information cc w/encls: See next page

March 21, 2006 Mr. James M. Levine Executive Vice President, Generation 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 -

REQUEST FOR ADDITIONAL INFORMATION REGARDING THE REVISED STATION BLACKOUT EVALUATION (TAC NOS. MC8787, MC8788, AND MC8789)

Dear Mr. Levine:

By letter dated October 28, 2005, Arizona Public Service submitted a revised Station Blackout evaluation for the Palo Verde Nuclear Generating Station Units 1, 2, and 3, increasing the coping duration from 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> to gain margin relative to nuclear safety.

The Nuclear Regulatory Commission (NRC) staff has reviewed the information provided and determined that additional information is required in order to complete the evaluation. The additional information being requested is enclosed. As discussed with Glenn Michael of your staff, the NRC staff is requesting a response within 30 days of the date of this letter.

If you have any questions, please contact me at 301-415-3062.

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, 50-529 and STN 50-530

Enclosure:

Request for Additional Information cc w/encls: See next page DISTRIBUTION:

PUBLIC RidsNrrLADJohnson RidsOgcRp LPLIV Reading RidsNrrPMMFields RidsAcrsAcnwMailCenter RidsNrrAdroDorlLplg RidsNrrDorlDpr RidsRgn4MailCenter (TPruett)

ADAMS ACCESSION NO: ML060760279 OFFICE NRR/LPL4/PM NRR/LPL4/LA NRR/LPL4/BC NAME MFields DJohnson DTerao DATE 3/21/06 3/21/06 3/21/06 OFFICIAL RECORD COPY

REQUEST FOR ADDITIONAL INFORMATION ARIZONA PUBLIC SERVICE COMPANY, ET. AL.

PALO VERDE NUCLEAR GENERATING STATION, UNITS 1, 2, AND 3 DOCKET NOS. STN 50-528, STN 50-529, AND STN 50-530 By letter dated October 28, 2005 (Agencywide Documents and Access Management System (ADAMS) Accession No. ML053120390), Arizona Public Service Company submitted a revised Station Blackout (SBO) evaluation for the Palo Verde Nuclear Generating Station (PVNGS),

Units 1, 2, and 3, increasing the coping duration from 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> to gain margin relative to nuclear safety.

The staff has reviewed the information provided and determined that the following additional information is required in order to complete the evaluation.

Questions Related to the Electrical Area

1. In Table 2 of the October 28, 2005, letter, main essential lighting panel load is shown as 90 kW. Table 8.3-3, page 8.3-6 of the Updated Final Safety Analysis Report indicates this load as 160 kW. Provide an explanation for this difference.

2. In the October 28, 2005, letter, it is stated that the 2-way radio system has a 4-hour battery system and will be transferred to the gas turbine generator (GTG). Is the load included in Table 2 of the amendment request? If so, please identify this load.

3. Please confirm that the loading (3364.3 kW) shown in Table 2 of the October 28, 2005, letter represents the worst case loading for both trains of all three units.

Questions Related to the Human Performance Area These questions are in reference to Item 7 of the Coping Study

1. With the exception of the operator actions in step D, are there any other new operator actions that take place after the actuation of the alternate alternating current (AAC) power source? This question also applies to the operator actions listed in Item 3, part A of Procedures. If so, what was the basis for including these particular actions as they relate to the extended coping period?

2. What was the justification for using the pressurizer vent valves as opposed to the auxiliary spray to control Reactor Coolant System (RCS) pressure after 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of an SBO and preceding operator actions in step D?

3. How will the simulator be modeled and validated to meet the estimated response times listed on Table 5 for the operators using the revised procedures?

Questions Related to the Reactor System Area

1. The PVNGS 16-hour SBO coping analysis was performed using the CENTS code to model the behavior of the RCS. Provide the basis for using the CENTS Code for this use.

2. The 16-hour SBO coping strategy includes several operator actions. For example, after the actuation of the AAC power source at one hour into the event, operator actions are necessary to (1) open the steam generator (SG) atmospheric dump valves (ADVs) for decay heat removal; (2) adjust the auxiliary feedwater system to match the ADV flow to maintain SG level; and (3) load the high-pressure safety injection (HPSI) pump onto the GTG-energized bus to deliver flow as the RCS pressure drops below the HPSI pump shutoff head to maintain RCS inventory, subcooling, and natural circulation. At four hours, the following operator actions are required to start a cooldown to shutdown cooling entry condition during the remaining 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> of the coping period: (1) adjusting ADVs hourly to sustain an approximately 30 oF/hr cooldown; and (2) opening the pressurizer vent valve to maintain the RCS pressure and inventory.

Describe how the CENTS Code was controlled to reflect these operator actions.

Palo Verde Generating Station, Units 1, 2, and 3 cc:

Mr. Steve Olea Mr. Hector R. Puente Arizona Corporation Commission Vice President, Power Generation 1200 W. Washington Street El Paso Electric Company Phoenix, AZ 85007 310 E. Palm Lane, Suite 310 Phoenix, AZ 85004 Mr. Douglas Kent Porter Senior Counsel Mr. John Taylor Southern California Edison Company Public Service Company of New Mexico Law Department, Generation Resources 2401 Aztec NE, MS Z110 P.O. Box 800 Albuquerque, NM 87107-4224 Rosemead, CA 91770 Mr. Thomas D. Champ Senior Resident Inspector Southern California Edison Company U.S. Nuclear Regulatory Commission 5000 Pacific Coast Hwy Bldg D1B P. O. Box 40 San Clemente, CA 92672 Buckeye, AZ 85326 Mr. Robert Henry Regional Administrator, Region IV Salt River Project U.S. Nuclear Regulatory Commission 6504 East Thomas Road Harris Tower & Pavillion Scottsdale, AZ 85251 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 Mr. Jeffrey T. Weikert Assistant General Counsel Chairman El Paso Electric Company Maricopa County Board of Supervisors Mail Location 167 301 W. Jefferson, 10th Floor 123 W. Mills Phoenix, AZ 85003 El Paso, TX 79901 Mr. Aubrey V. Godwin, Director Mr. John Schumann Arizona Radiation Regulatory Agency Los Angeles Department of Water & Power 4814 South 40 Street Southern California Public Power Authority Phoenix, AZ 85040 P.O. Box 51111, Room 1255-C Los Angeles, CA 90051-0100 Mr. Craig K. Seaman, General Manager Regulatory Affairs and Mr. Brian Almon Performance Improvement Public Utility Commission Palo Verde Nuclear Generating Station William B. Travis Building Mail Station 7636 P. O. Box 13326 P.O. Box 52034 1701 North Congress Avenue Phoenix, AZ 85072-2034 Austin, TX 78701-3326 March 2006

Palo Verde Generating Station, Units 1, 2, and 3 cc:

Ms. Karen O'Regan Environmental Program Manager City of Phoenix Office of Environmental Programs 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 March 2006