ML18153C525
| ML18153C525 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 01/17/1991 |
| From: | Reyes L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| References | |
| NUDOCS 9102130098 | |
| Download: ML18153C525 (27) | |
Text
- OFFICIAL* COPY Docket Nos. 50-280, 50-281 License Nos. DPR-32, DPR-37 Virginia Electric and Power Company ATTN:
Mr. W. L. Stewart Senior Vice President - Nuclear 5000 Dominion Boulevard Glen Allen, VA 23060 Gentlemen:
SUBJECT:
ENFORCEMENT CONFERENCE
SUMMARY
{NRC INSPECTION REPORT NOS. 50-280/90-36 AND 50-281/90-36)
This letter refers to the Enforcement Conference held at our request on January 8, 1991.
This meeting concerned activities authorized for your Surry facility.
The issue discussed at this conference related to the macrofouling of th~ service water system that caused blockage of service water flow to the recirculation spray heat exchangers, rendering the recirculation spray system potentially inoperable.
A list of attendees, a meeting summary, and a copy of your handout are enclosed.
We are continuing our review of this issue to determine the appropriate enforcement action.
In accordance with Section 2.790 of the NRC's "Rules of Practice," Part 2, Title 10, Code of Federal Regulations, a copy of this letter and its enclosures will be placed in the NRC Public Document Room.
Should you have any questions concerning this matter, please contact us.
Enclosures:
- 1. List of Attendees
- 2.
Meeting Summary
- 3.
Handout cc w/encls:
E. W. Harrell Vice President - Nuclear Operations Virginia Electric & Power Company 5000 Dominion Boulevard
- Glen Allen, VA 23060 Sincerely, Original signed by Luis A. Reyes, Director Division of Reactor Projects (cc w/encls cont'd - See page 2) 9102130098 910117 PDR ADOCK 05000280 G
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Virginia Electric and Power Company (cc w/encls cont 1d)
J. P. 0 1Hanlon Vice President - Nuclear Services Virginia Electric & Power Company 5000 Dominion Boulevard Glen Allen, VA 23060 M. R. Kansler Station Manager Surry Power Station P. 0. Box 315 Surry, VA 23883 M. L. Bowling, Jr., Manager Nuclear Licensing Virginia Electric & Power Co.
5000 Dominion Boulevard Glen Allen, VA 23060 Sherlock Holmes, Chairman Board of Supervisors of Surry County Surry County Courthouse Surry, VA 23683 W. T. Lough Virginia Corporation Commission Division of Energy Regulation P. 0. Box 1197 Richmond, VA 23209 Michael W. Maupin Hunton and Williams P. 0. Box 1535 Richmond, VA 23212 C. M. G. Buttery, M.D., M.P.H.
Department of Health 109 Governor Street Richmond, VA 23219 Attorney General Supreme Court Building 101 North 8th Street Richmond, VA 23219 Commonwealth of Virginia bee w/encls:
(See page 3) 2 JAN 1 7 1991
Virginia Electric and Power Company 3
bee w/encls:
A.11 NRC Attendees
~cument Control Desk J. Lieberman, DOE B. Buckley, NRR NRC Resident Inspector U.S. Nuclear Regulatory Commission Route 1, Box 166 Surry, VA 23883 NRC Resident Inspector
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ENCLOSURE 1 LIST OF ATTENDEES Virginia Electric and Power Company W. Stewart, Senior Vice President, Nuclear E. Harrell, Vice President, Nuclear Operations F. Moore, Vice President, Nuclear Engineering Services M. Kansler, Station Manager, Surry J. Price, Assistant Station Ma*nager, Surry M. Bowling, Manager, Nuclear Licensing G. Kane, Station Manager, North Anna J. Stall, Assistant Station Manager, North Anna D. Sommers, Licensing Supervisor, Surry J. Bolin, Supervisor, Biological Operations Nuclear Regulatory Commission J. Milhoan, Deputy Regional Administrator, Region II (RII)
E. Merschoff, Deputy Director, Division of Reactor Projects (DRP) RII T. Peebles, Branch Chief, Division of Reactor Safety, RII M. Sinkule, Branch Chief, DRP, RII P. Fredrickson, Section Chief, DRP, RII G. Belisle, Section Chief, DRP, RII W. Holland, Senior Resident Inspector, Surry, DRP, RII M. Lesser, Senior Resident Inspector, North Anna, DRP, RII G. Jenkins, Director, Enforcement and Investigation Coordination Staff (EICS), RII L. Keller, Project Engineer, DRP, RII B. Uryc, Senior Enforcement Coordinator, EICS, RII A. Ruff, Project Engineer, DRP, RII H. Berkow, Director, Project Directorate II-2, Office of Nuclear Reactor Regulation (NRR)
L. Engle, Licensing Project Manager, North Anna, NRR NRC Representatives (Participation by Teleconferencing)
B. Buckley, Licensing Project Manager, Surry, NRR R. Pedersen, Office of Enforcement (OE)
A. Allmon, OE
ENCLOSURE 2 ENFORCEMENT CONFERENCE
SUMMARY
An Enforcement Conference was held at the NRC's Region II Office with Virginia Electric and Power Company (Virginia Power) on January 8, 1991, to discuss Surry' s reduced service water (SW) flow through the recirculation spray heat exchangers (RSHX) due to blockage from in-plant macrofouling sources in the SW system.
After the NRG Deputy Regional Administrator opened the meeting by briefly discussing the specific NRG concerns, the Senior Vice President -
Nuclear, provided opening remarks for Virginia Power.
He stated that excessive macrofoul ing from the hydroid growth that flourishes during the hot _summer months was the principal cause of this condition and that the event was thoroughly investigated.
He also stated that the initial corrective action was prompt and thorough in that the operating unit was immediately shut down when the low flow condition was discovered during testing and the SW system for both units were inspected and cleaned.
Long term corrective action is being formulated to prevent a recurrence of this condition.
The Station Manager gave the formal presentation which followed the items and topics listed in a handout (Enclosure 3).
Questions asked by the NRG participants during and after the presentation were answered satisfactorily by the licensee's representatives.
The safety significance and evaluation of issues as listed in Enclosure 3 were disGussed in detail.
Virginia Power's position was that, since the actual SW flow requirements vary as a function of river temperature and the design SW flow temperature is in most cases considerably higher than river temperature, no significant hazard to the public health and safety existed.
The NRG Deputy Regional Administrator closed the meeting by thanking Virginia Power for the presentation.
ENCLOSURE 3 VIRGINIA POWER SURRY POWER STATION ENFORCEMENT CONFERENCE JANUARY 8, 1991 RECIRCULATION SPRAY HEAT EXCHANGER OPERABILITY
AGENDA RSHX OPERABILITY ASSESSMENT EVENT ASSESSMENT ISSUES DESIGN CONSIDERATIONS SYSTEM DESCRIPTION ROOTCAUSE CORRECTIVE ACTIONS SAFETY SIGNIFICANCE CONCLUSIONS
EVENT ASSESSMENT MACROFOULING BLOCKAGE OF RSHXs DURING TESTING WAS DUE TO INPLANT SOURCES, NOT TRANSPORTED DEBRIS, AS A RESULT OF HIGH VELOCITY INRUSH DURING FLOW INITIATION
ISSUES ABILITY TO HAVE ANTICIPATED OR DETECTED EARLIER THE RSHX MACROFOULING BLOCKAGE MECHANISM OF INPLANT DISLODGEMENT SAFETY SIGNIFICANCE OF THE REDUCED SW WATER FLOW TO RSHXs
DESIGN CONSIDERATIONS FOR SW TO RSHXs RETURN CONTAINMENT TO SUBATMOSPHERIC PRESSURE WITHIN ONE HOUR AND MAINTAIN SUBATMOSPHERIC DESIGN BASES SW FLOW REQUIREMENT FOR THE INITIAL 2 HOURS IS 12,000 GPM (i.e. 2 RSHXs)
DESIGN BASES SW FLOW REQUIREMENT AFTER 24 HOURS IS 6,000 GPM (i.e. 1 RSHX)
DESIGN BASES SW TEMPERATURE ASSUMED TO BE 92°F ACTUAL SW FLOW REQUIREMENTS VARY AS A FUNCTION OF ULTIMATE HEAT SINK (RIVER) TEMPERATURE
Figure 3 Surry Service Water Average Temperature and SW Flow Requirements 90 -
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DESIGN CRITERIA 10 CFR 100 LIMITS 25 REM WHOLE BODY AND 300 REM THYROID DOSE AT THE EXCLUSION AREA BOUNDARY DURING THE FIRST TWO HOURS GDC 19 LIMITS 5 REM WHOLE BODY AND 30 REM THYROID TO THE MAIN CONTROL ROOM DURING THE FIRST 30 DA VS
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Figure 1 Service Water Flow Path To ASHX*s
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SERVICE WATER FLOW TO RECIRCULATION SPRAY HEAT EXCHANGERS SURRY POWER STATK)N Figure2 EL-11'-e"
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ROOT CAUSE IN.ADEQUATE CONSIDERATION OF CONSEQUENCES OF MARINE.
GROWTH IN SW PIPING INRUSH AND DISLODGEMENT PHENOMENON NOT PREVIOUSL V ANTICIPATED OR DETECTED FOCUS ON MACROFOULING BLOCKAGE ISSUES WAS DIRECTED ENTIREL VAT TRANSPORT MECHANISMS
ABILITY TO HAVE ANTICIPATED
- INPLANT DISLODGEMENT AS SOURCE OF RSHX MACROFOULING BLOCKAGE MICROFOULING WAS INITIAL CONCERN FOR RSHX RSHXs REPLACED IN 1988 OUTAGES TUBE MICROFOULING ISSUES DISCUSSED IN IR 88-27 (8/17/88)/
!R88-32 (12/15/88)/NRC MANAGEMENT MEETING (1/26/89)
MAiNTAINING RSHXs DRY SURVEILLANCE OF RSHXs TO ENSURE DRY LA YUP REFURBISHMENT & MODIFICATIONS TO INLET & OUTLET*
MOVs TO MITIGATE WATER INGRESS
ABILITY TO HAVE ANTICIPATED INPLANT DISLODGEMENT AS SOURCE OF RSHX MACROFOULING BLOCKAGE CONTINUED MACROFOULING BLOCKAGE BEING EXPERIENCED ON OTHER PLANT COMPONENTS WAS CONSIDERED TO BE BY TRANSPORT ONLY
- ENGINEE~ING REVIEW OF TRAVELING SCREENS (SPRING 1990)
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EVALUATION OF CANAL IDENTIFIED NO HYDROID COLONIES ON CANAL LINER
- OPERATIONAL EXPERIENCE SUPPORTED TRANSPORT THEORY RSHX PERFORMANCE CONSIDERED NOT LIKELY TO BE AFFECTED BY TRANSPORT MACROFOULING BECAUSE OF LOWER STEADY-STATE SW SYSTEM FLOWRATES AND LOWER INTAKE VELOCITIES
ABILITY TO HAVE ANTICIPATED INPLANT DISLODGEMENT AS SOURCE OF RSHX MACROFOULING BLOCKAGE CONTINUED SW TO RSHX PIPING INSPECTED AND LOCALLY CLEANED DURING 1988-89 OUTAGES SIL T/BIOFOULING OBSERVED ADDRESSED IN NRC MANAGEMENT MEETING (10/26/88)
COMMITMENT TO INSPECT & CLEAN PRIOR TO REST ART WAS MET CONDITIONS FOR ATYPICAL HYDROID GROWTH DURING 1989-1990 EXTENDED GROWING SEASON DUE TO WARMER THAN AVERAGE WINTER & SUMMER LOWER THAN AVERAGE RAINFALL (SALINITY EFFECT)
LOW SYSTEM FLOW CONDITIONS DURING EXTENDED OUTAGES ii FIRST OPERATIONAL IMPACT EXPERIENCED WITH ESW PUMPS IN SEPTEMBER 1990 GENERIC LEITER 89-13 REQUIRED SW INSPECTION AND MAINTENANCE PROGRAM WAS IMPLEMENTED DURING 1990 REFUELING OUTAGE
CORRECTIVE ACTIONS i
FOLLOWING INITIAL UNIT 1 RSHX FLOW TESTING
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INITIAL FLOW TEST IDENTIFIED FLOW DEGRADATION ASSESSED OPERABILITY BASED ON EMPIRICAL DATA DETERMINED RETESTING REQUIRED RETEST INDICATED SIGNIFICANT FLOW BLOCKAGE RSHXsDECLAREDINOPERABLE UNIT 2 SHUTDOWN PER TECHNICAL SPECIFICATIONS FORMAL NRC NOTIFICATION OPEN COMMUNICATIONS WITH NRC
CORRECTIVE ACTIONS CONTINUED PRIOR TO UNIT STARTUP INITIATED RESTORATION PLAN ON BOTH UNITS (INSPECT & CLEAN)
FILLED UPSTREAM PIPING TO LIMIT SW INRUSH EFFECTS RETESTED UNIT 1 AFTER CLEANING TO ESTABLISH DESIGN ADEQUACY PLACED OPERATIONAL RESTRICTIONS ON BOTH UNITS BASED ON EXPECTED SW TEMPERATURE PERIODICALL VAL TERNATE SW HEADERS TO RETARD HVDROID GROWTH I
HELD NRC.MANAGEMENT MEETING PRIOR TO RESTART (11/7/90)
SUBMITIED LER (11/21/90)
LONG TERM SOLUTIONS ARE BEING DEVELOPED
SAFETY SIGNIFICANCE MINIMUM SAFEGUARDS ANALYSIS (DBA)
CONTAINMENT DOES NOT STAY SUBATMOSPHERIC OFFSITE DOSES WITHIN 10CFR100 CRITERIA
DOSES WITHIN GDC 19 CRITERIA UTILIZING REALISTIC SOURCE TERM (LHSI PUMP MAINTAINS FUEL AT LESS THAN FUEL OVERTEMPERATURE CONDITION)
PROBABILITY OF OCCURRENCE IS VERY LOW (1.7 E-8/YR)
MAXIMUM CONTAINMENT PRESSURE IS NOT INCREASED SO THE PROBABILITY OF CONTAINMENT FAILURE IS NOT INCREASED
SAFETY SIGNIFICANCE CONTINUED NORMAL SAFEGUARDS ANALYSIS (NO LOOP)
- CONTAINMENT DOES DEPRESSURIZE WITHIN FIRST HOUR
- DOSES WITHIN 10CFR100 AND GDC 19 CRITERIA OPERATED CONTAINMENT DEPRESSURIZATION CAPABILITY SYSTEMS IN ACCORDANCE WITH TECHNICAL SPECIFICATIONS
CONCLUSIONS THE INRUSH AND DISLODGEMENT MACROFOULING MECHANISM WAS IDENTIFIED BY THE LICENSEE TESTING PROGRAM CORRECTIVE ACTIONS WERE PROMPTLY TAKEN TO ENSURE PLANT OPERATIONS CONSISTENT*WITH TECHNICAL SPECIFICATIONS INCLUDING SHUTDOWN OF OPERATING UNIT ACTUAL MACROFOULING MECHANISM UNEXPECTED (SEVERITY OF INRUSH VERSUS TRANSPORT OF DEBRIS)
NRC HAS BEEN KEPT THOROUG.HL Y APPRISED OF RSHX ISSUES NO SIGNIFICANT HAZARD TO PUBLIC HEAL TH & SAFETY EXISTED
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VIRGINIA POWER LONG TERM SOLUTIONS TO SURRY SW e
MACROFOULING ISSUE F. K. MOORE VICE PRESIDENT -
NUCLEAR ENGINEERING SERVICES
i STRATEGY TO RESOLVE MACROFOULING IN SURRY SW SYSTEM I
UTILIZE CHEMICAL TREATMENT TO CONTROL HYDROIDS DURING WARM WEATHER ROUTINELY CHECK RIVER SALINITY AND SW pH, OXYGEN, AMMONIA, AND SALINITY TO DETERMINE PROPENSITY FOR RAPID HVDROID GROWTH PERIODICALLY INSPECT AND CLEAN SW PIPING CONTINUE SW PIPE DESIGN CHANGE TO UPGRADE PIPE COATINGS
STRATEGY TO RESOLVE MACROFOULING IN SURRY SW SYSTEM CONTINUED PERFORM TYPE 2 DESIGN STUDIES TO DETERMINE NEED FOR SW ENCHANCEMENT INCLUDING ANALYSIS OF THE SW ECOSYSTEM MODIFICATIONS TO REDUCE MACROFOULING
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i MODIFICATIONS TO REDUCE BIOLOGICAL GROWTH BY CHEMICAL CONTROL, COATINGS, OR OTHER METHODS GENERIC-LETTER 89-13 PROGRAM INITIATED DURING UNIT 1 REFUELl~G OUTAGE ONGOING SW PIPE DCP PROGRAM INCLUDES SW PIPE INSPECTION & CLEANING SW PIPE REPAIR AS NECESSARY SW PIPE RECOATING WITH MORE DURABLE MATERIAL
SCHEDULE MANAGEMENT MEETING WITH NRC START CHEMICAL INJECTION INTERIM ASSESSMENT OF HYDROID BIOLOGY COMPLETE TYPE 2 STUDY FEBRUARY 6, 1991 MARCH 1991.
JULY1991 APRIL 1992