ML17305A666

Requests Progress Summary of Efforts Re Multiple CEA Drop Events,Including Discussions of Identified & Proposed Improvements & Implementation Schedules for Selected Improvements.Info Requested within 30 Days of Ltr Receipt

ML17305A666
Person / Time
Site:	Palo Verde
Issue date:	04/06/1990
From:	Chan T Office of Nuclear Reactor Regulation
To:	Conway W ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
References
NUDOCS 9004180164
Download: ML17305A666 (6)

Text

April 6, 1990 Docket Nos. 50-528, 50-529 and 50-530 Mr. )lilliam'F. Conway Executive Vice President.

Arizona Public Service Company Post Office Box 52034 Phoenix, Arizona 85072-2034

Dear Mr. Conway:

DISTRIBUTION NRC 5 Local PDRs PD5 Reading C. Trammell J. Zwolinski P.

Shea T.

Chan S. Peterson OGC E. Jordan ACRS (10)

SUBJECT:

MULTIPLE CONTROL ELEMENT ASSEMBLY (CEA)

DROP EVENTS - PALO VERDE NUCLEAR GENERATING STATION (PVNGS)

By letter dated October 25, 1989, Arizona Public Service Company (APS) forwarded to the NRC "Justification for Continued Operation-Control Element Assembly (CEA) Drop Events, Revision 3."

This document provided the basis for APS'onclusion that Unit 2 could safely operate until the end of its operating cycle, with known ground faults in certain CEA coil assemblies.

The JCO also described a program which would be implemented to identify and.

evaluate improvements that would ensure the remoteness of multiple CEA drop events or to ensure that fuel design limits are maintained in the event of multiple CEA drops.

Me request that within 30 days from receipt of this letter, APS provide a

progress summary of efforts in this area which include discussions of identi-fied and proposed improvements, and implementation schedules of the selected improvements for each Palo Verde unit.

He also ask that you describe the means by which APS will verify the effectiveness of the immediate corrective actions with regard to eliminating lift coil ground faults (i.e., sleeving of electrical leads, limited replacement of coils and inspection of coils), and substantiate the certainty of the postulated failure mechanism of the lift coil leads.

If you should have any questions on this matter, please contact me.

Sincerely, PO~

AQQCK 00406 4280gbq 05000gpe t

PQC cc:

See next page

• See previous concurrence original signed by Terence L. Chan Terence L. Chan, Senior Project Manager Project Directorate V

Division of Reactor Projects - III IV, V and Special Projects Office of Nuclear Reactor Regulation DRSP/PD5*

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UNITED STATES NUCL'EAR REGULATORY COMMISSION'ASHINGTON, D. C. 20555 Apri,l 6, 1990 Docket -IIos. 50-528, 50-529 and 50'-530 Nr..william F.

Conway Executive Vice President Arizona Public Service Company Post Office 'Box 52034

Phoenix, Arizona 85072-2034

SUBJECT:

MULTIPLE CONTROL ELEMENT ASSEMBLY (CEA)

DROP EVENTS - PALO VERDE NUCLFAR GENERATING STATION (PVNGS)

By letter dated October 25, 1989, Arizona Public Service Company (APS) forwarded to the NRC "Justification for Continued Operation-Control Element Assembly (CEA) Drop Events, Revision 3."

This document provided the basis for APS'onclusion that Unit 2 could safely operate until the end ot its operating cycle, with known ground faults in certain CEA coil assemblies.

The JCO also described a program which would.be implemented to identify and evaluate improvements that would ensure the remoteness of multiple CEA drop events or to ensure that fuel design l.imits are maintained in the event of multiple CEA drops.

Me request that within 30 days from receipt of this letter, APS provide a

progress summary of efforts in this area which include discussions of identi-fied and proposed improvements, and implementation schedules of the selected improvements for each Palo Verde unit.

Me also ask that you describe the means by which APS wi 11 verify the effectiveness of the immediate corrective actions with regard to eliminating lift coil ground faults (i.e., sleeving of electrical

.leads, limited replacement of coils and inspection of coils),

and substantiate the certainty of the postulated failure mechanism of the lift coil leads.

If you should have any.questions on this matter, please contact me.

Sine ely cc:

See next page erence L. Chan, Senior Project

Manager, roject.Directorate V

Division of Reactor Projects - III IV, V and Special Projects Office of Nuclear Reactor Regulation

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'Mr. Willi'am F.

Conway Arizona Public Service Company Palo 'Verde CC:

Arthur C. Gehr, Esq.

Snell 5 Wilmer

,3100 Valley Center Phoenix, Arizona 85073 Charles R. Kocher, Esq. Assistant Council James A.. Boeletto, Esq.

'Southern California Edison Company P. 0.

Box 800

Rosemead, Cali.fornia 91770 Senior Resident 'Inspector U.S. Nuclear Regulatory Commission HC-03 Box 293-NR Buckeye, Arizona 85326 Regional Administrator,,Region V

U. S. Nuclear 'Regulatory Commission 1450 Maria Lane Suite 210 Walnut Creek, California 94596 Mr. Charles B. Bririkman

.Washington Nuclear Operations Combustion Engineering, Inc.

12300 Twinbrook Parkway, Suite 330

.Rockvi lie, Maryland 20852 Mr.. Char 1 es Tedford, Director Arizona Radiation Regulatory Agency 4814, South 40 Street Phoenix,,Arizona 85040 Chairman Maricopa County Board of Supervisors 111 South Third Avenue Phoenix, Arizona 85003 Mr. Jack R.

Newman Newman. 5.Holtzinger. P.C.

1615 L Street, NW, Suite.1000 Washington,

'DC 20036 Mr. Jack N. Bailey Vice President Nuclear Safety and Licensing Arizona Publ.ic Service Company P.O.

Box 52304 Phoenix', Arizona 85072-2034 Mr. James M'. L.evine Vice President, Nuclear Production, Arizona Public Service Company P..O.

Box 52304

Phoenix, Arizona:

85072-2034

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