ML15244A588
| ML15244A588 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 12/07/1989 |
| From: | Wiens L Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8912150007 | |
| Download: ML15244A588 (18) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 December 7, 1989 Docket Nos.
50-269, 50-270, and 50-287 LICENSEE:
Duke Power Company FACILITY: Oconee Nuclear Station, Units 1, 2 and 3
SUBJECT:
SUMMARY
OF OCTOBER 17, 1989 MEETING ON EMERGENCY FEEDWATER RUNOUT CONDITION On October 17, 1989, representatives of Duke Power Company (DPC) made a presentation to the NRC staff cn the issue of prevention of emergency feedwater (EFW) pump runout under conditions of reduced steam generator pressure. The meeting was held at DPC's request. The DPC presentation included a historical background of the issue, a description of the EFW system, a description of the pump runout conditions, discussion of modifications which had been evaluated to correct the condition (primarily cavitating venturis) and the result of their efforts.
DPC's evaluation showed that none of the proposed system modifications were desirable for the Oconee system.
The primary problem with the cavitating venturis was the indication from shop tests that significant system vibration coulo be induced from their installation. The vibrations could be of such magnitude as to lead to rapid failure of EFW piping or components. Other proposed modifications either led to an inappropriate increase in system complexity or the cost of the modification could not be justified.
The NRC representatives recognized the present situation with the EFW system.
DPC was encouraged to continue to emphasize proper steam generator water level control procedures during operator training courses, and to continue to review the EFW system on a routine basis for possible system improvenant which would minimize the possibility of EFW pump runout. In addition, DPC was requested to provide the results of their vibration studies of the cavitating venturis.
DPC agreed to this request. In a subsequent discussion with DPC, it was agreed that DPC would submit a letter formally documenting that the evaluation of EFW system modifications committed to in Licensee Event Report 86-010 was complete and that no desirable modification had been identified.
SODCF
.2-2 Meeting attendees-are lisied in Enclosure 1. Handouts distributed by DPC during the presentation are provided in Enclosure 2.
/s/
Leonard A. Wiens, Project Manager Project Directorate 11-3 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation
Enclosures:
As stated cc w/enclosures:
See next page DISTRIBUTION FOR MEETING
SUMMARY
DATED:
Facility:
Oconee Nuclear Station, Units 1, 2 and 3 Docket File J. Wermiel 8-D-1 NRC PDR C. McCracken 8-D-1 Local PDR D. Hood 14-H-25 PDII-3 Reading T. Murley, 12-G-18 J. Sniezek 12-G-18 S. Varga 14-E-1 D. Matthews 14-H-25 R. Ingram 14-H-25 L. Wiens 14-H-25 OGC 15-B-18 E. Jordan MNBB-3302 ACRS (10)
P-315 B. Borchardt 17-0-19 OFCf :P 3 :
4 NAME :LWi nscb DM hews DATE :IF/Il/89
/89 OFFICIAL RECORD COPY Document Name: OCONEE
SUMMARY
10/26
Oconee Nuclear Station Units Nos. 1, 2 and 3 cc:
Mr. A. V. Carr, Esq.
Mr. Paul Guill Duke Power Company Duke Power Company P. 0. Box 33189 Post Office Box 33189 422 South Church Street 422 South Church Street Charlotte, North Carolina 28242 Charlotte. North Carolina 28242 J. Michael McGarry, III, Esq.
Bishop, Cook, Purcell & Reynolds Mr. Alan R. Herdt, Chief 1400 L Street, N.W.
Project Branch #3 Washington, D.C. 20005 U.S. Nuclear Regulatory Commission 101 Marietta Street, NW, Suite 2900 Mr. Robert B. Borsum Atlanta, Georgia 30323 Babcock & Wilcox Nuclear Power Division Ms. Karen E. Long Suite 525 Assistant Attorney General 1700 Rockville Pike N. C. Department of Justice Rockville, Maryland 20852 P.O. Box 629 Raleigh, North Carolina 27602 Manager, LIS NUS Corporation Mr. H. B. Tucker, Vice President 2536 Countryside Boulevard Nuclear Production Department Clearwater, Florida 34623-1693 Duke Power Company 422 South Church Street Senior Resident Inspector Charlotte, North Carolina 28242 U.S. Nuclear Regulatory Commission Route 2, Box 61C Seneca, South Carolina 29678 Regional Administrator, Region II U.S. Nuclear Regulatory Commission 101 Marietta Street, N.W., Suite 2900 Atlanta, Georgia 30323 Mr. Heyward G. Shealy, Chief Bureau of Radiological Health South Carolina Department of Health and Environmental Control 2600 Bull Street Columbia, South Carolina 29201 Office of Intergovernmental Relations 116 West Jcnes Street Raleigh, North Carolina 27603 County Supervisor of Oconee County Walhalla, Suuth Carolina 29621
EFW RUNOUT MEETING Attendees ORG Name Len Wiens NRR/PDII-3 Paul Guill Duke/NPD Tom Curtis Duke/Oconee Hugh Hammond Duke/Design/Mech Systems Wally Houston Duke/Design/Mech Systems B. L. Peele Duke/Design Engr.
Tom Coutu Duke/Oconee Gregory D. Lewis Duke/Design Engr.
- j. S. Wermiel NRR/DST/SPLB Conrad McCracken NRR/SPLB Darl Hood NRR/PDII-3 OCONEE NUCLEAR STATION EMERGENCY FEEDWATER RUNOUT CONDITION NRC CONFERENCE OCTOBER 17, 1989
AGENDA
- INTRODUCTION/HISTORY M. TUCKMAN SYSTEM DESCRIPTION H. HAMMOND
- DESCRIPTION OF RUNOUT H. HAMMOND CAVITATING VENTURI PROBLEMS H. HAMMOND TRAINING & PROCEDURES M. TUCKMAN
SUMMARY
M. TUCKMAN
DUKE ATTENDEES MIKE TUCKMAN OCONEE STATION MANAGER TOM COUTU OCONEE OPERATIONS ENGINEER TOM CURTIS OCONEE COMPLIANCE MANAGER JACK PEELE DESIGN ENGINEERING PROJECTS MANAGER, OCONEE DIVISION WALLY HOUSTON DESIGN ENGINEERING SUPERVISOR HUGH HAMMOND DESIGN ENGINEER GREG LEWIS DESIGN ENGINEER PAUL GUILL LICENSING ENGINEER
PURPOSE TO ALLOW A MORE DETAILED DISCUSSION OF DUKE'S RESPONSE TO THE OCONEE EFW PUMP RUNOUT ISSUE
HISTORY/BACKGROUND 80-82 IEB 80-04 ADDRESSES EFWP RUNOUT OCONEE EFWP RUNOUT PROTECTION FOUND ACCEPTABLE 1/86 OCONEE SIMULATOR RESPONSE PROMPTS DESIGN INVESTIGATION INTO EFW PUMP RUNOUT 5/86 - 6/86 OCONEE EFW SSFI INVESTIGATION INTO RUNOUT PROBLEM ACCELERATED 9/86 LER 269/86-10 CONCERNING EFW RUNOUT SUBMITTED LONG TERM RESOLUTION TO BE PROVIDED LATER 5/87 SUPPLEMENT TO LER 269/86-10 IDENTIFIED CAVITATING VENTURIS AS LONG TERM RESOLUTION IMPLEMENTATION SCHEDULE (UlEOC11, U2EOC10, U3EOC10) 6/88 NRC INFORMED OF REVISED SCHEDULE
HISTORY/BACKGROUND (CONTINUED) 6/88 NRC INFORMED OF REVISED SCHEDULE FOR UNIT 3 (U3EOC11) 12/88 NRC INFORMED OF CAVITATING VENTURI VIBRATION PROBLEM 6/89 NRC INFORMED OF CHANGE IN COMMITMENT DUKE REQUESTED MEETING TO DISCUSS RATIONALE FOR DECISION
SYSTEM DESCRIPTION PRIMARY FLOW PATH ALTERNATE PATHS INITIATION - CONTROL OTHERSOURCES
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PUMP RUNOUT WHAT IT IS HIGH FLOW -+
LOW NPSHA WHAT IT COULD DO LONG TERM CAVITATION WEAR PERFORMANCE DEGRADATION SHORT TERM DEPENDS ON PUMP TYPE LOSS OF HYDRAULIC SUPPORT POTENTIAL FOR RAPID FAILURE HOW IT COULD OCCUR LOW SG PRESSURE WIDE OPEN CONTROL VALVE SCENARIOS MSLB (WORST CASE)
OTHERS - MFDWLB, SBLOCA, LOAC HOW TO PREVENT LIMIT FLOW RATE LIMIT TIME OF RUNOUT OPERATION
CAVITATING VENTURI PROBLEMS (VIBRATION)
BACKGROUND SHOP TEST RESULTS OTHER UTILITY DATA EVALUATION SIGNIFICANCE OF VIBRATION SCREENING CRITERIA COMPARISON TO FAILURES QUALIFICATION POSSIBLE?
FIND WORST POINT DYNAMIC MODEL MULTIPLE MEASUREMENTS COMPARE TO CRITERIA OTHER OPTIONS REVIEWED COMPLEX/PROBLEMATIC
OCONEE VENTURI SHOP TEST >10 ips 40 epVENTURI DATA
.X FAILURE
.4
.z 3
4 6
6 10 zQ 3
40 00 aoio 100 20010 Vibration Frequency. Ha FIGURE 2 COMPARISON OF PIPING VIBRATION LEVELS WITH 0.5 IPS VELOCITY CRLITERIA Note:
Indicated vibration limits are *foir average piping system co.nstructed in accordance with good engineering practices. Make additional allowances for critical appli Cationsp unrhinfoirced branch connecio.ns# etc*
EFW THROTTLING/RUNOUT CHRONOLOGY TRAINING AND PROCEDURES SG ISOLATION, INCLUDING FDW 315/316, HISTORICALLY PART OF OPERATOR TRAINING FOR LINE BREAKS 1985 ORIGINAL EMERGENCY OPERATOR PROCEDURE (EOP) PROVIDES EFW OVERCOOLING GUIDELINES (APPROXIMATELY 435 GPM) 8/86 AFTER SSFI, RUNOUT ISSUE ADDRESSED IN SEVERAL WAYS TRAINING PACKAGE PREPARED, REVIEWED BY OPERATORS 500 GPM EFWP LIMIT AND GUIDELINES ADDED TO EFW OPERATING PROCEDURE (OP)
STUDY REQUESTED FOR POSSIBLE MOD TO LIMIT FLOW EFW RUNOUT, FLOW LIMITS, ETC. ADDED TO OPERATOR LICENSE AND REQUAL TRAINING CLASSROOM AND SIMULATOR CONTINUES TO PRESENT
EFW THROTTLING/RUNOUT CHRONOLOGY (CONTINUED) 11/86 ADDITIONAL GUIDELINES/ENCLOSURE FOR CORRECTING HIGH EFW FLOW ADDED TO OP 4/87 NEW OPERATIONS MANAGEMENT PROCEDURE (OMP) IDENTIFIED 500 GPM EFWP LIMIT TO BE COMMITTED TO MEMORY BY OPERATORS 2/88 NEW ABNORMAL PROCEDURE (AP) ON LOSS OF FDW INCORPORATED EFWP FLOW GUIDANCE 4/88 EOP REVISED TO INCLUDE EFWP 500 GPM LIMIT
SUMMARY
EFW RUNOUT ISSUE FOCUSED IN 1986 NEED FOR THROTTLING IDENTIFIED BY DUKE NRC INPUT VIA 1986 SSFI SYSTEM REMAINS RELIABLE CAVITATING VENTURI ENHANCEMENT TO EFW UNWORKABLE FOR OCONEE SYSTEM VIBRATION PROBLEM DISCOVERED AFTER CONSIDERABLE EXPENSE, AND AFTER NRC INFORMED OF DECISION TO INSTALL OTHER OPTIONS COMPLICATE SYSTEM, COSTLY EVALUATION OF POSSIBLE ENHANCEMENTS TO CONTINUE (SPIP RESPONSE)
EFW RUNOUT PREVENTION EMPHASIZED IN OPERATOR TRAINING AND PROCEDURES OPERATOR BURDEN ISSUE OPERATOR BURDEN CONSIDERED ACCEPTABLE BY DUKE, BWOG REPORT