ML16148A663
| ML16148A663 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 07/22/1992 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML16148A662 | List: |
| References | |
| 50-269-92-14, 50-270-92-14, 50-287-92-14, EA-92-117, NUDOCS 9208110069 | |
| Download: ML16148A663 (16) | |
Text
ENCLOSURE 1 NOTICE OF VIOLATION Duke Power Company Docket Nos. 50-269, 50-270, Oconee Nuclear Station and 50-287 Units 1, 2, and 3 License Nos. DPR-38, DPR-47, and DPR-55 EA 92-117 During an NRC inspection conducted on May, 24 -
June 19, 1992, violations of NRC requirements were identified. In accordance with the "General Statement of Policy and Procedure for NRC Enforcement Actions," 10 CFR Part 2, Appendix C, the violations are listed below:
A.
Technical Specification (TS) 3.4, Emergency Feedwater System, states that the reactor shall not be heated above 250 degrees Fahrenheit unless two 100 percent Emergency Feedwater flow paths are operable.
The TS Bases defines a 100 percent flowpath as the flow path to either steam generator including associated valves and piping capable of being supplied by either the turbine or associated motor driven pump.
Contrary to the above, the Unit 1 reactor was heated above 250 degrees Fahrenheit on May 11, 1992, and operated until May 25, 1992, with only one 100 percent flowpath operable. Steam generator 1A Emergency Feedwater level control valve, 1FWD-315, was incapable of opening automatically on an Emergency Feedwater actuation signal. The failure of this valve rendered one of the two Emergency Feedwater flowpaths inoperable.
This is a Severity Level IV violation (Supplement I) and is applicable to Unit 1 only.
B.
Technical Specification 6.4.1 requires that the station be operated in accordance with approved procedures.
Station Performance Manual, Section 4.7, Support of Reactor Trips, Revision dated July 24, 1991, requires that a post trip review be conducted following a reactor trip.
Contrary to the above, the Oconee Nuclear Station Post Trip Review conducted after the Unit 1 reactor trip on May 8, 1992 was inadequate in that it did not require the reviewer to verify that all safety systems 9208110069 920721 PDR ADOCK 05000269 PDR
Duke Power Company 2 Docket Nos. 50-269, 50-270, Oconee Nuclear Station and 50-287 Units 1, 2, and 3 License Nos. DPR-38, DPR-47, and DPR-55 EA 92-117 performed as expected following a reactor trip. This resulted in the "A" train of the Emergency Feedwater system being inoperable and undetected.
This is a Severity Level IV Violation (Supplement I) and is applicable to all three Units.
Pursuant to the provisions of 10 CFR 2.201, Duke Power Company is hereby required to submit a written statement or explanation to the U.S. Nuclear-Regulatory Commission, ATTN: Document Control Desk, Washington, D.C. 20555 with a copy to the Regional Administrator, Region II, a copy to the Oconee NRC Resident Inspector, within 30 days of the date of the letter transmitting this Notice of Violation (Notice). This reply should be clearly marked as a "Reply to a Notice of Violation" and should include for each violation:
(1) the reason for the violation, or, if contested, the basis for disputing the violation, (2) the corrective steps that have been taken and the results achieved, (3) the corrective steps that will be taken to avoid further violations, and (4) the date when full compliance will be achieved.
If an adequate reply is not received within the time specified in this Notice, an order or Demand for information may be issued as to why the license should not be modified, suspended, or revoked, or why such other action.as may be proper should not be taken. Where good cause is shown, consideration will be given to extending the response time.
Dated.at Atlanta, Georgia this 22nd day of July 1992
ENCLOSURE 2 LIST OF ATTENDEES U. S. Nuclear Requlatory Commission S. D. Ebneter, Regional Administrator, Region II (RII)
J. R. Johnson Acting Director, Division of Reactor Projects (DRP),
RII A. F. Gibson, Director, Division of Reactor Safety (DRS), RII E. W. Merschoff, Deputy Director, DRS, RII G. R. Jenkins, Director, Enforcement and Investigations Coordination Staff, RII C. F. Evans, Regional Counsel, RII P. H. Skinner, Acting Chief, Reactor Projects Branch 3, DRP, RII G. A. Belisle, Chief, Reactor Projects Section 3A, DRP, RII L. A. Wiens, Project Manager, Project Directorate 11-3, Nuclear Reactor Regulation (NRR)
W. K. Poertner, Resident Inspector, Oconee, DRP, RII B. B. Desai, Resident Inspector, Oconee, DRP, RII B. Uryc, Senior Enforcement Specialist, RII W. H. Miller, Jr., Project Engineer, Project Section 3A, DRP, RII Attended by Teleconference W. M. Troskoski, Enforcement Specialist, Office of Enforcement Duke Power Company J. W. Hampton, Vice President, Oconee Nuclear Site (ONS)
H. B. Barron, Station Manager, ONS B. L. Peele, Engineering Manager, ONS D. B. Coyle, System Engineering Manager, ONS M. E. Patrick,. Regulatory Compliance, ONS
ENCLOSURE 3 OCONEE NUCLEAR SITE OPERATION WITH AN INOPERABLE EFDW SYSTEM FLOWPATH ENFORCEMENT CONFERENCE JULY 17, 1992
AGENDA INTRODUCTION J. W. Hampton EVENT DESCRIPTION B. L. Peele SAFETY SIGNIFICANCE B. L. Peele POST TRIP REVIEW PROCESS B. L. Peele CORRECTIVE ACTIONS B. L. Peele CLOSING REMARKS J. W. Hampton
EVENT DESCRIPTION At 0342 on May 8th, Unit I tripped from 14% full power following a FDW transient which caused Emergency Feedwater (EFDW) to actuate This FDW transient did not trip main feedwater EFDW was secured following verification that main FDW flow and SG levels were responding appropriately
EVENT DESCRIPTION Trip response was reviewed utilizing Post Trip Review procedure which requires normal 15 minute plots for plant parameters, EFDW was on for 43 Seconds Conclusions of Post Trip Review were that trip responses were normal Discrepancy in EFDW flow was not identified 2
MAX "I
MIII
03:37 :01 lI[0 It IIW:1,110UO f:1lI 03: 52:01 STY TAG MIN MAX EGU DESCRIPTOR NODE A5047 0.00 6.00 MPPH FDW FLOW A (SEL) 0C1030 A5048 0.00 6.00 MPPH FDW FLOW B (SEL)
OC1830 D5812 FALSE TRUE REACTOR TRIP 0C1030 03:44:31.90 05-08-92
MAX MI N 03:37:01
- - I 1 -' U No M
M s
'*'o 4.-
03:52: 01 STY TAG MIN MAX EGU DESCRIPTOR HODE A5039 0.00 250.00 INCH SG STARTUP LEVEL A (SEL) 0C1830 A5049 0.90 250.90 INCH SC STARTUP LEVEL B (SEL) 0C1830 D502 FALSE TRUE REACTOR TRIP 0C1930 13:44:31.90 05-88-92
MAX I
rI II I
03:37:01 M
l3:52:01 STY TAG MIN MAX EGl DESCRIPTOR NODE A5049
.100 1200. 0 GPM EFDN FLOW A OC1630 A550 0.00 1200. 0 GPM EFD FLOW B 0C1030 D5892 FALSE TRUE REACTOR TRIP 0C1930 03:44:31.90 05-08-92
Uppj UPPER SURGE SUPCE
.TAW TANK AB-R8 372 232 STEAM AID Re GEN.
I A
MOTO DRIEN FTO 5 FROM CONDENSER EMGE C 374 OTHER UNITS HOTWELL PUMP A 7W 38 C-391 0
HER UNITS 368 MAIN FEEDWATER TURBINE DRIVEN EMERGENCY FDW PUiMP.
96 69 MAIN FEEDWATER TO S FROM OTHER UNITS TOB8 FROM 38S4 OTHER UNITS AB RE 282 316 310i 233 STE AM AS RS GE N.
282 MOTOR DRIVEN EMERGENCY FDW PUMP OCONEE EMERGENCY FEEDWATER SIMPL IFIED SCHEMATIC
EVENT DESCRIPTION Following a shutdown for RCP seal repair, a stroke test on IFDW-315 revealed that it would not operate in the "Auto" mode Subsequent investigation revealed that a solenoid for enabling the "Auto" valve function had failed. This type failure had been previously identified in LER 287/91-07 Solenoid was replaced with a newer model which was consistent with corrective actions outlined in the previous LER Corrective actions had been completed on Unit 2 and are still planned on Units 1 & 3 Further evaluation (June 10th) of post trip response during RX trip on May 8th revealed that the "A" EFDW train exhibited no flow, ie. 1FDW-315 was not operable 3
SAFETY SIGNIFICANCE Vulnerable to single failure on "B" EFDW train Manual operation still available on "A" EFDW train Valves were tested manually operable prior to startup on May 10/11 Manual operation is a demonstrated and approved method of EFDW system operation The EOP instructs Operators to take manual control of EFDW in the event no flow is available Alternate means of RCS heat removal were still available 4
POST TRIP REVIEW PROCESS Framework of the current process has been utilized since 1983 at Oconee, McGuire, and Catawba. These procedures were transmitted to the NRC in response to Generic Letter 83-28 (Salem ATWS)
Level of detail is comparable to the current INPO good practice (OP-21 1)
Post Trip Review procedure was intended to be a guide and not an all inclusive checklist and to be performed by qualified individuals experienced in reviewing plant transients Performed by two Shift Managers, an Engineering Supervisor, and the Duty Reactor Engineer Focus was not on EFDW flow response since main FDW was still available and EFDW had been secured 5
CORRECTIVE ACTIONS Revise Post Trip Review process to include EFDW flow verification following actuation at all Duke sites All 3 sites will evaluate additional parameters that may need to be included in the Post Trip Review process Emphasis will be placed on verification of significant system responses during the Post Trip Review process.
Solenoid valve replacements will continue on original schedule Valve stroke testing frequency has been increased from cold shutdown to quarterly 6
CLOSING REMARKS All three Duke sites. will he reviewing the Post Trip Review process for enhancements Aware of and had reported the root cause of the failure and had a plan in place to replace solenoids Low safety significance 7