ML062860202

Request for Additional Information Regarding Technical Specification Amendment Submittal (TAC Nos. MD2831, MD2832, and MD2833)

ML062860202
Person / Time
Site:	Palo Verde
Issue date:	10/18/2006
From:	Fields M NRC/NRR/ADRO/DORL/LPLIV
To:	James M. Levine Arizona Public Service Co
Fields M, NRR/DORL/LP4, 415-3062
References
TAC MD2831, TAC MD2832, TAC MD2833
Download: ML062860202 (7)

Text

October 18, 2006Mr. James M. LevineExecutive 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 TECHNICAL SPECIFICATION AMENDMENT SUBMITTAL (TAC NOS. MD2831, MD2832, AND MD2833)

Dear Mr. Levine:

By letter dated August 16, 2006, Arizona Public Service Company submitted a licenseamendment request for the Palo Verde Nuclear Generating Station, Units 1, 2, and 3. Therequest would revise several Surveillance Requirements (SRs) in Technical Specification(TS) 3.8.1, "AC Sources - Operating," to allow these SRs to be performed, or partiallyperformed, in reactor modes that currently are not allowed by the TSs. The proposed changes would also require certain SRs to be performed at a power factor of 0.9 if performed with theemergency diesel generators synchronized to the grid, unless grid conditions do not permit.The Nuclear Regulatory Commission (NRC) staff has reviewed the information provi ded anddetermined 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 60 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 ManagerPlant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor RegulationDocket Nos: STN 50-528, 50-529 and STN 50-530

Enclosure:

Request for Additional Information cc w/encl: See next page October 18, 2006Mr. James M. LevineExecutive 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 TECHNICAL SPECIFICATION AMENDMENT SUBMITTAL (TAC NOS. MD2831, MD2832, AND MD2833)

Dear Mr. Levine:

By letter dated August 16, 2006, Arizona Public Service Company submitted a licenseamendment request for the Palo Verde Nuclear Generating Station, Units 1, 2, and 3. Therequest would revise several Surveillance Requirements (SRs) in Technical Specification(TS) 3.8.1, "AC Sources - Operating," to allow these SRs to be performed, or partiallyperformed, in reactor modes that currently are not allowed by the TSs. The proposed changes would also require certain SRs to be performed at a power factor of 0.9 if performed with theemergency diesel generators synchronized to the grid, unless grid conditions do not permit.The Nuclear Regulatory Commission (NRC) staff has reviewed the information provi ded anddetermined 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 60 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 RegulationDocket Nos: STN 50-528, 50-529 and STN 50-530

Enclosure:

Request for Additional Information cc w/encl: See next pageDISTRIBUTION

PUBLICLPLIV ReadingRidsNrrDorlDprRidsNrrDorlLpl4RidsRgn4MailCenter (TPruett)APal, DERidsAcrsAcnwMailCenterRidsNrrLAJBurkhardtRidsNrrPMMFieldsRidsOgcRpADAMS ACCESSION NO: ML062860202OFFICELPL4/PMLPL4/LALPL4/BCNAMEMFieldsLFeizollahiDTeraoDATE10/17/0610/18/0610/18/06OFFICIAL RECORD COPY REQUEST FOR ADDITIONAL INFORMATION ARIZONA PUBLIC SERVICE COMPANY, ET AL.PALO VERDE NUCLEAR GENERATING STATION, UNITS 1, 2, AND 3DOCKET NOS. STN 50-528, STN 50-529, AND STN 50-530By letter dated August 16, 2006, Arizona Public Service Company submitted a licenseamendment request for the Palo Verde Nuclear Generating Station (Palo Verde or PVNGS),Units 1, 2, and 3. The request would revise several Surveillance Requirements (SRs) inTechnical Specification (TS) 3.8.1, "AC Sources - Operating," to allow these SRs to beperformed, or partially performed, in reactor modes that currently are not allowed by the TSs. The proposed changes would also require certain SRs to be performed at a power factor of 0.9 if performed with the emergency diesel generators synchronized to the grid, unless gridconditions do not permit.The staff has reviewed the information provided and determined that the following additionalinformation is required in order to complete the evaluation. 1.Confirm that proposed power factor of 0.9 is the calculated worst case power factor. The confirmation should include actual calculated power factor of each diesel generator (DG) for loss of offsite power (LOOP) and LOOP with loss-of-coolant accident loading.2.The Bases for SR 3.8.1.10 implies that the bus voltage can be varied by adjusting theDG field excitation when operating in parallel with the grid. Adjusting the field excitation should only momentarily affect the bus voltage. The grid voltage is primarily controlled by the transmission system operators and the automatic voltage regulators installed onthe large generating units tied to the grid. However, the staff does believe that potentially high-bus voltage may prevent the DG from obtaining the power factor limitspecified in the TS due excessive excitation, and under these conditions the proposed Note is warranted. Provide analysis or operating data to demonstrate that the voltageon the emergency bus can be varied by adjusting the field excitation of the DG when operating in parallel with the grid. Otherwise, the Bases for SR 3.8.1.10 should berevised to delete this condition.3.The Bases state that house loads must be transferred from the auxiliary transformers tothe startup transformers in order to lower the voltage on the emergency bus. The voltage on the emergency bus must be lower in order to meet the power factor requirements of SR 3.8.1.10 and SR 3.8.1.14. This manipulation of the offsite powercircuits to perform surveillance is unusual and could perturb the onsite alternating current electrical distribution systems. Normally this SR is performed during shutdown.

Provide assurance that manipulation of the offsite power circuits would not significantlyincrease the probability of LOOP.

4.Provide a detailed description of how the SR 3.8.1.9 is performed.5.On page 12 of the application, it is stated that "only one DG per unit is paralleled tooffsite power at any one time and any offsite grid disturbances would only possibly affect one operable DG." Confirm that at PVNGS no more than one DG to be paralleled to theoffsite power at the same time. 6.On page 12 of the application, it is stated that "at PVNGS when the DG full load rejectSR is performed at shutdown, the voltage transients experienced by the loads on the associated bus are considered minimal (an approximate 10 percent step change (400 VAC) in the bus voltage at the 4.16 kV level, with voltage recovery within 1 second." Discuss the impact of this voltage transient on a degraded voltage relay.

Also, since the voltage at the safety buses during power operation are relatively lower during shutdown, what will be the voltage transient due to a full load rejection test duringpower operation?7.On page 12 of the application, it is stated that "If a LOP [loss of offsite power] occursduring testing, the DG either trips on over current or continues to run, depending upon if the resulting load is in excess of the DG's load rating. If the load is excessive, the DG will trip on over current and the DG breaker will trip automatically on a DG shutdownsignal." Discuss how the DG will be started and DG breaker closed once the overcurrent relay trips the DG? Will it involve manual resetting of the relays? If so, discussthe time associated with the manual resetting of the relay.8.Confirm that SR 3.8.1.9 and 3.8.1.10 will not be scheduled during periods where thepotential for grid or bus disturbance increases (i.e., storm, grid emergencies, etc.).9.Discuss administrative controls to preclude performing these SRs during othermaintenance and test conditions that could have adverse effects on the offsite power system or plans for restricting additional maintenance or testing of safety relatedsystems that depend on the remaining DG as a source. Additionally, discuss if theremaining DG were to become inoperable while the other DG is being tested, would the test be aborted?10.Discuss whether the Transmission System Operator is notified in advance that a DG isgoing to be taken out for surveillance testings on-line.11.Discuss what action will be taken if degraded grid conditions occur during the DGsurveillance testing.12.The new Note added in SR 3.8.1.10 and 3.8.1.14 states that "If performed with the DGsynchronized with offsite power, it shall be performed at a power factor of 0.9. However, if grid conditions do not permit, the power factor limit is not required to be met.

Under this condition the power factor shall be maintained as close to the limit as practicable." The staff understands that the Palo Verde units have difficulty maintaining this power factor during these SRs. (a)Provide a discussion regarding the acceptable power factor during these SRsperformed at high grid voltage conditions (what is meant by as close to the limit as practicable). (b)Provide an assurance that the Note will not be used routinely or used forconvenience. (c)Describe the grid voltage that would not permit the power factor limit to besatisfied and how often these grid conditions are expected to occur in the future. (d)Provide the nominal grid voltage.

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

cc:March 2006Mr. Steve OleaArizona Corporation Commission 1200 W. Washington Street Phoenix, AZ 85007Mr. Douglas Kent PorterSenior Counsel Southern California Edison Company Law Department, Generation Resources

P.O. Box 800 Rosemead, CA 91770Senior Resident InspectorU.S. Nuclear Regulatory Commission

P. O. Box 40 Buckeye, AZ 85326Regional Administrator, Region IVU.S. Nuclear Regulatory Commission Harris Tower & Pavillion 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064ChairmanMaricopa County Board of Supervisors 301 W. Jefferson, 10th Floor Phoenix, AZ 85003Mr. Aubrey V. Godwin, DirectorArizona Radiation Regulatory Agency 4814 South 40 Street Phoenix, AZ 85040Mr. Craig K. Seaman, General ManagerRegulatory Affairs and Performance Improvement Palo Verde Nuclear Generating Station Mail Station 7636 P.O. Box 52034 Phoenix, AZ 85072-2034Mr. Matthew BenacAssistant Vice President Nuclear & Generation Services El Paso Electric Company 340 East Palm Lane, Suite 310 Phoenix, AZ 85004Mr. John TaylorPublic Service Company of New Mexico 2401 Aztec NE, MS Z110 Albuquerque, NM 87107-4224Mr. Thomas D. ChampSouthern California Edison Company 5000 Pacific Coast Hwy Bldg D1B San Clemente, CA 92672Mr. Robert HenrySalt River Project 6504 East Thomas Road Scottsdale, AZ 85251Mr. Jeffrey T. WeikertAssistant General Counsel El Paso Electric Company Mail Location 167 123 W. M illsEl Paso, TX 79901Mr. John SchumannLos Angeles Department of Water & Power Southern California Public Power Authority P.O. Box 51111, Room 1255-C Los Angeles, CA 90051-0100Mr. Brian AlmonPublic Utility Commission William B. Travis Building P. O. Box 13326 1701 North Congress Avenue Austin, TX 78701-3326 Palo Verde Generating Station, Units 1, 2, and 3

cc:March 2006Ms. Karen O'ReganEnvironmental Program Manager City of Phoenix Office of Environmental Programs 200 West Washington Street Phoenix AZ 85003