ML17300A249
| ML17300A249 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde  |
| Issue date: | 07/08/1986 |
| From: | Licitra E Office of Nuclear Reactor Regulation |
| To: | Van Brunt E ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR |
| References | |
| NUDOCS 8607170408 | |
| Download: ML17300A249 (6) | |
Text
July 8, 1986 Docket Nos.:
50-528, 50-529 and 50-530 Mr. E.
E.
Van Brunt, Jr.
Executive Vice President Arizona Nuclear Power Project Post Office Box 52034 Phoenix, Arizona 85072-2034
Dear Mr. Van Brunt:
DIS 8UTION cet )e NRC PDR LPDR PD7 Reading JLee EALicitra JPartlow EJordan BGrimes ACRS (10)
- Attorney, ELD
Subject:
Request for Additional Information - Palo Verde Unit 1 LER No.86-006 The staff is;evaluating the event, reported in LER No.86-006, which occurred on Ja'nuary 9, 1986 during a load rejection test on Palo Verde unit 1.
During this event, a fast transfer of the reactor coolant pump buses to offsite power did not occur and the reactor coolant pumps coasted down faster than expected.
In order to complete our evaluation of this event, we require additional
-information.
The specific information needed is.identified in the enclosed request and has been discussed with your staff.
We ask that you, provide the requested information by July 31, 1986.
If you have any questions regarding this letter, please let me know.
Sincerely,
Enclosure:
As stated E. A. Licitra, Project Manager PWR Project Directorate No.
7 Division of PWR Licensing-B cc:
See next page dos gg EAL itra/yt g
ighton Vpl86 Vg/86 Bg07$ 70408 g6070W PDR ADOCK 05000528 PDR
J tl
)'
i>
ii II, J
Mr. E.
E.
Van Brunt, Jr.
Arizona Nuclear Power Project Palo Verde CC:
Arthur C. Gehr, Esq.
Snell 5 Wilmer 3100 Valley Center Phoenix, Arizona 85073 Mr. James M. Flenner, Chief Counsel Arizona Corporation Commission 1200 West Washington Phoenix, Arizona 85007 Charles R. Kocher, Esq. Assistant Council James A. Boeletto, Esq.
Southern California Edison Company P. 0.
Box 800
- Rosemead, California 91770 Mr. Mark Ginsberg Energy Director Office of Economic Planning and Development 1700 West Washington - 5th Floor Phoenix, Arizona 85007 Mr. Wayne Shirley Assistant Attorney General Bataan Memorial Building Santa Fe, New Mexico 87503 Kenneth Berlin, Esq.
Winston 5 Strawn Suite 500 2550 M Street, NW Washington, DC 20037 Ms. Lynne Bernabei Government Accountability Project of the Institute for Policy Studies 1901 Que Street, NW Washington, DC 20009 Ms. Jill Morrison 522 E. Colgate Tempi, Arizona 85238 Mr. Charles B. Brinkman, Manager Washington Nuclear Operations Combustion Engineering, Inc.
7910 Woodmont Avenue Suite 1310
- Bethesda, Maryland 20814 Mr. Ron Rayner P. 0.
Box 1509
- Goodyear, AZ 85338 Mr. Roy Zimmerman U.S. Nuclear Regulatory Commission P. 0.
Box 239 Arlington, Arizona 85322 Ms. Patricia Lee Hourihan 6413 S. 26th Street Phoenix, Arizona 85040 Regional Administrator, Region V
U.'. Nuclear Regulatory Commission 1450 Maria Lane Suite 210 Walnut Creek, California 94596
Enclosure PALO VERDE RE VEST FOR
~ADD FT0%FL INFORMATION 19 RCP COASTDO L
TO RCP BUSES 1.
What is the coastdown rate of the RCPs assumed in the FSAR and what are the factors or assumptions on which this value is based?
2.
How much faster was the coastdown recorded on January 9,
1986 com-pared to the coastdown in the SAR?
What were the safety implications as determined by APS?
Discuss the consequences on each transient and accident analyzed in FSAR that is affected by the faster flow coastdown.
3.
What are the proposed corrective actions to assure that this deviation of the RCP coastdown rate will not result in an unreviewed safety question?
4.
What are the other station electrical loads on the RCP buses that caused a faster coastdown of RCPs?
5.
Loss of power to the RCP's can occur as a result of a fast transfer failure, from the trip of the RCP bus input breaker or from the trip of a RCP breaker.
Does the coastdown analysis in the SAR consider the worst case conditon of loss or degradation of power supply to the RCP's?
6.
Will the synch-check relay function be modified as a result of the January 9 event?
If so, how will it be changed?
7.
Do the revised calculations for the RCP coastdown rate include all loads on the RCP buses or just a few selected loads?
8.
Even if the fast transfer is successful, there is a period of time in cycles (Hz) during which RCP buses will be disconnected from the source of power (due to difference in time between breaker tripping and closing).
During this time, the decaying voltage undergoes a phase shift.
guantify this phase shift.
Is this phase shift of the residual voltage a potential for out of phase re-energization of the RCP buses when fast transfer completes?
9.
Did the CE evaluation of the January 9 event result in recommendations to reduce the penalty factor that was added in COLSS by APS?
4