IR 05000269/1986010
| ML16161A738 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 06/05/1986 |
| From: | Brownlee V, Bryant J, Sasser M, Tedrow J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML16161A737 | List: |
| References | |
| 50-269-86-10, 50-270-86-10, 50-287-86-10, NUDOCS 8606190581 | |
| Download: ML16161A738 (9) | |
Text
pj REGt UNITED STATES
NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTA STREET, N.V ATLANTA, GEORGIA 30323 Report Nos:
50-269/86-10, 50-270/86-10, and 50-287/86-10 Licensee:
Duke Power Company 422 South Church Street Charlotte, N.C. 28242 Facility Name:
Oconee Nuclear Station Docket Nos.:
50-269, 50-270, 50-287 License Nos.:
DPR-38, DPR-47, and DPR-55 Inspection Conducted:
irch 11 - April 14, 1986 Inspectors: __
e(
5 ryant/Date/Si gned SasserDate Si'gned d ow Da e Signed Approved by: __
V. L. Bownlee, Section Chief, (Acting)
Date' Signed Division of Reactor Projects SUMMARY Scope: This routine, announced inspection was conducted on site in the areas of operations, surveillance, maintenance, verification of engineered safety features lineups, refueling activities, and an annual emergency dril Results: Of the six areas inspected, no items of noncompliance or deviations were identifie I 8 0 6 190581 B60609 pDR ADOCK 050026
REPORT DETAILS 1. Licensee Employees Contacted
- M.S. Tuckman, Station Manager J.N. Pope, Superintendent of Operations T.B. Owen, Superintendent of Maintenance
- D.S. Compton, Technical Specialist Other licensee employees contacted included technicians, operators, mechanics, security force members, and staff engineer Resident Inspectors
- J.C. Bryant
- M.K. Sasser J.E. Tedrow
- Attended exit intervie.
Exit Interview The inspection scope and findings were summarized on April 15, 1986 with those persons indicated in paragraph 1 abov The licensee did not identify as proprietary any of the materials provided to or reviewed by the inspectors during this inspectio. Licensee Action on Previous Enforcement Matters Not inspecte. Unresolved Items Unresolved items were not identified on this inspectio. Plant Operations The inspectors reviewed plant operations throughout the reporting period to verify conformance with regulatory requirements, technical specifications (TS),
and administrative control Control room logs, shift turnover records, and equipment removal and restoration records were reviewed routinely. Interviews were conducted with plant operations, maintenance, chemistry, health physics and performance personne Activities within the control rooms were monitored on an almost daily basi Inspections were conducted on day and on night shifts, during week days and on weekend Some inspections were made during shift change in order to evaluate shift turnover performanc Actions observed were conducted as required by Operations Management Procedure 2-The complement of
licensed personnel on each shift inspected met or exceeded the requirements of TS. Operators were responsive to plant annunciator alarms and were cognizant of plant condition Plant tours were taken throughout the reporting period on a routine basi The areas toured included the following:
Turbine Building Auxiliary Building Unit 1 Reactor Building Units 1 and 3 Penetration Rooms Units 1,2, and 3 Electrical Equipment Rooms Units 1,2, and 3 Cable Spreading Rooms Station Yard Zone within the Protected Area Standby Shutdown Facility Units 1 and 2 Spent Fuel Pool During the plant tours, ongoing activities, housekeeping, security, equipment status, and radiation control practices were observe Unit 1 remained in cold shutdown throughout the report period. The unit was shutdown on February 13 for the cycle 9 refueling outag Initial startup date was April 10, 1986, however maintenance on the low pressure turbine has delayed startup, currently scheduled for April 2 Unit 2 operated at essentially full power throughout the report perio Unit 3 began the report period at 100% power. On March 29 power was reduced to 90% due to high bearing temperature on 3D2 heater drain pump. Following repair of the heater drain pump, the unit was returned to power on March 3 No violations or deviations were identifie.
Surveillance Testing The surveillance tests listed below were reviewed and/or witnessed by the inspectors to verify procedural and performance adequac The completed tests reviewed were examined for necessary test prerequisites, instructions, acceptance criteria, technical content, authorization to begin work, data collection, independent verification where required, handling of deficiencies noted, and review of completed wor The tests witnessed, in whole or in part, were inspected to determine that approved procedures were available, test equipment was calibrated, prerequisites were met, tests were conducted according to procedure, test
results were acceptable and systems restoration was complete Surveillances witnessed in whole or in part are as follows:
PT/1/A/0150/06 Mechanical Penetration Leak Rate Test, Penetration #22 IP/2/A/305/3D RPS Channel +/-D' Calibration and Functional Test PT/1/A/600/10 Reactor Coolant System Leakage PT/1/A/261/06 Condenser Circulating Water System Gravity Flow Test PT/1/A/610/01J Emergency Power Switching Logic Engineered Safeguards Actuation Keowee Emergency Start Test PT/1/A/203/06 Low Pressure Injection System Performance Test, LPI +/-1A' Pump Completed surveillances reviewed are as follows:
PT/1/A/0150/06 Mechanical Penetration Leak Rate Test PT/0/A/0150/05 Electrical Penetration Leak Rate Test, Unit 1 IP/1/B/125/1 Strong Motion Accelerograph Monthly Verification, 01/06/86 IP/1/B/125/4 Strong Motion Accelerograph Semi Annual Functional Test, 10/21/85 IP/1/B/125/5 Strong Motion Accelerograph Annual Calibration, 10/21/85 IP/1/B/125/2A 2G Peak Accelerometer Quarterly Calibration, 10/21/85 IP/1/B/125/2B 2G Peak Accelerometer Refueling Calibration IP/1/B/125 Seismic Trigger Quarterly Calibration and Test, 01/10/86 PT/1/A/0202/12 High Pressure Injection System Engineered Safeguards Test TT/1/A/0600/03 Motor Driven Emergency Feedwater Flow Test No violations or deviations were identifie. Maintenance Activities Maintenance activities were observed and/or reviewed during the reporting period to verify that work was performed by qualified personnel and that approved procedures in use adequately described work that was not within the skill of the trade. Activities, procedures and work requests were examined to verify proper authorization to begin work, provisions for fire, cleanliness, and exposure control, proper return of equipment to service, and that limiting conditions for operation were me Maintenance witnessed in whole or in part:
MP/0/A/1200/2A Reassembly of Vent Valve 1LWD-369 WR 29006B Hinge Pin on LPI Pump A Dischage Check Valve, 1LP-31 WR 29009B Repair of Valve LP-9 WR 29010B Repair of Valve LP-12
Maintenance work requests reviewed in detail:
WR 24397B Replace +/-2A' Seal Supply Filter WR 90716C Repair Equalizing Valve on RB Personnel Hatch Outer Door, Unit 3 WR 24250B Troubleshoot, Repair Unit 1 Core Flood Tank Level Instrument Discrepancy WR 56196 Preventative Maintenance on Unit 3 Personnel Hatch WR 24140B Repair Unit 3 Reactor Building Post Accident Water Level Indication WR 24474B Repair 3LP-17. Valve will not fully open electricall No violations or deviations were identifie.
Oconee Seismic Instrumentation On February 13, 1986, a minor seismic event occurred near the Oconee Nuclear Station (see report 80-04, paragraph 8).
Additionally, IE correspondence dated February 19 reviewed the potential failure of seismic instruments, recommending that the NRC regions factor maintenance and testing of seismic instruments into routine inspection program The resident inspectors conducted an inspection of the seismic instrumentation at the site along with associated surveillance test Several types of instruments are in us A strong motion acceleration system records acceleration data in three planes and has a lower sensitivity of 0.01 g acceleratio Peak recording accelerometers are installed at various locations within the Unit 1 reactor building, with sensitivity range from 0.01 to 2.0 g. A third type of instrument is the seismic trigger, or actuating pendulum, calibrated to provide a control room alarm when the design basis seismic condition (0.05 g) occur The surveillance history of the instruments was reviewed to verify maintenance and testing on the required frequency. Surveillance procedures for each type of instrument were reviewed in detail for procedural conformanc Inspection of the location of seismic instruments will continue during the next report perio No violations or deviations were identifie.
Required Instrumentation Not In Service During Refueling Operations During refueling of Unit 1, on two occasions instrumentation required by technical specifications (TS)
for fuel movement was found to be out of service, as described belo a. Core Geometry Changes Made Without Core Subcritical Neutron Flux Monitor (NI) Being Operable (Personnel Error)
T.S. 3.8.2 requires continuous monitoring of core subcritical neutron flux by at least two neutron flux monitors whenever core geometry is bing changed. On March 12, 1986, while fuel was being reloaded into the Unit 1 core, one of two nuclear instruments (NI-1) in service was deenergized for 2 1/2 hours as a result of a power interruption, before the loss was discovere When the loss of NI-1 was noted, fuel movement was immediately terminate During the period of NI-1 inoperability, NI-2 was completely operational and provided chart, scaler and audible (clicker) monitoring of neutron flu Also, NI-2 detector was in the more favorable position to monitor the reactor area being fuele The strip recorder showing the count rate of NI-1 and NI-2 was located behind the refueling RO and he did not notice that NI-1 had dropped down scal He was relying on the scaler connected to NI-2 and the audible clicker of both NIs. Also, he relied on being informed by the nuclear control operator who would receive an audible and visual alarm in the event of loss of an N Unfortunately, loss of NI-1 coincided with a loss of power to a number of control room indications, due to a modification being installe The nuclear operator was very busy recovering power and did not notify the refueling R The refueling SRO detected the loss of NI-1 and immediately stopped refueling operation The SRO had NI-1 placed on line and had the refueling booth rearranged so that all instruments could be seen more easily. The SRO terminated construction activity which was in progress nearby and erected a barrier to stop local traffic, since the noise level might have influenced the refueling operator's failure to detect loss of the NI-1 clicker. The SRO counselled all operators involved (all experienced personnel) and then resumed refueling operation b. Vent Gaseous Radiation Monitor Removed From Service During Refueling Operations Because of Personnel Erro On March 14 Radiation Instrument Alarm (RIA)-45, the vent gaseous radiation monitor, was removed form service for periods of 4 minutes and 70 minutes while refueling was in progres RIA-45 provides automatic reactor building purge isolation in the event of an acciden The first event occurred when maintenance personnel, with the unit supervisor's permission, were making a routine maintenance check of RIA The mechanics found RIA-43 to have a low flow rate and cut the air pump off for 4 minutes while they determined the cause. The RIA-45 sample is also furnished by the same pump. The mechanics obtained from the unit supervisor a priority request to repair RIA-4 The unit supervisor did not recognize that this would also remove RIA-45 from service, nor did he obtain the shift supervisor's permission, as required by the shift superviso After repairs began, a health physics technician who came to the work area to provide compensatory sampling for RIA-43, recognized that RIA-45 was also out of service and notified the shift supervisor one hour after the pump was shut down for maintenanc Refueling operations were terminated immediately and were not resumed until repairs were completed and instrument performance verifie The licensee's data base search to determine if these were recurring events found only one incident report involving nuclear instruments which was caused by a personnel error. That event occurred in 1975, eleven years ag Similarly, a data base search revealed that RIA-45 has not previously been out of service during refueling activitie Though the two events are violations of technical specifications they will not be cited since they meet the conditions as stated in 10 CFR 2, Appendix C, the NRC's program to encourage and support licensee initiative for self identification and correction of problems in that: The problems were identified by the license b. They fit into Severity Level IV or c. They were reported as require They were corrected immediately and measures were taken to prevent recurrenc e. They were not violations that could reasonably be expected to have been prevented by corrective action taken on a previous violatio. Refueling Activities (60710)
The inspectors completed an inspection of Unit 1 refueling outage activities during the report period. Refueling activities were observed in the Unit 1 control room, the reactor building, and the Unit 1 and 2 spent fuel poo These activities were witnessed to verify compliance with Technical Specification required conditions for fuel movemen No violations or deviations were identifie.
Measurement of End of Cycle Moderator Temperature Coefficient On April 10 the NRC was notified by the licensee that the Oconee units may have been operated in a condition outside that defined by the final safety analysis report (FSAR).
Based on recent analyses it appears that the end of cycle (EOC)
moderator temperature coefficient (MTC)
has been more negative (less conservative) than that assumed in the FSAR for the steam line break accident. The condition may have existed on all three units towards the end of their last eighteen month cycle No Oconee unit is presently in this conditio Concerns that higher burnup fuel cycles could cause the EOC MTCs to be less conservative led to the licensee's desire to verify the capability of the design codes to accurately calculate EOC MT Additional MTC measurements near the EOC were necessary for comparison with EOC values extrapolated from beginning of cycle (BOC) data taken during startup physics test Results of EOC measurements on Unit 1 just prior to the cycle 9 refueling outage indicated an MTC more negative than assumed in the FSA However these results were suspect due to heat balance discrepancies during the test which could have affected the results. In order to resolve these discre pancies, the licensee repeated the test for Unit 2 on March 11, collecting data at 274 effective full power days (EFPD).
Results of the Unit 2 test indicate that the earlier results were valid, therefore the indication of EOC MTC being more negative than the FSAR assumption was considered correc Based on this information the licensee notified the NR The following corrective actions have been completed or are planned by the licensee. New safety analyses have verified the acceptability of the more negative MT The.revised analyses assume Hot Zero Power, All Rods In (HZP,ARI) rather than Hot Full Power, All Rods Out (HFP,ARO) as used in the current FSAR calculations. This assumption is acceptable based on a reactor trip which would occur during a steam break accident. The current operating cores are within the bounds of the new analyse A revision to the FSAR will be necessary to document the.new analyse Another contributing factor is a positive MTC bias, historically added to the licensee's code predictions, which was initially justified and documented by Babcock and Wilco The MTC positive bias is no longer considered justified and will not be used in the futur The licensee has indicated plans to perform HZP, ARI measurements of MTC near the EOC of Units 2 or 3. These measurements are required to verify the revised calculations based on HZP, AR The residents will continue to follow this until additional measurements are complete. This will be listed as inspector followup item 269,270,287/86-10-01; end of cycle moderator temperature coefficient measurement.
Licensee Event Reports The inspectors reviewed nonroutine event reports to verify the report details met license requirements, identified the cause of the event, described corrective actions appropriate for the identified cause, and adequately addressed the event and any generic implication In addition, as appropriate, the inspectors examined operating and maintenance logs, and records and internal investigation report Personnel were interviewed to verify that the report accurately reflected the circumstances of the event, that the corrective action had been taken or responsibility assigned to assure completion, and that the event was reviewed by the licensee, as stipulated in the Technical Specification The following event reports were reviewed:
(Closed)
LER 269/85-04, Gaseous Waste Disposal Tank Emptied Without a Redundant Sample Analysis (Closed) LER 269/85-09, Inoperabilitly of Several Radioactive Effluent Monitors (Closed) LER 269/85-11, Interim Radwaste Building Gaseous Effluent Flow Rate Monitor Inoperable (Closed) LER 269/85-12, Reactor Building Tendon Inspection and Reporting Intervals Exceeded (Closed) LER 270/85-01, Both Unit 2 Reactor Building Spray Systems Made Unavailable During Testing (Closed)
LER 270/85-08, Reactor Shut Down Because of Reactor Coolant System Leakage Greater Than 1 GPM (Closed) LER 270/85-09, Unit Vent Radiation Monitor Inoperable Without Establishing Manual Sampling (Closed) LER 287/85-03, Unsuccessful Attempt to Open an Electric Motor Operated Valve From the Control Room (Closed)
LER 287/85-04, Missed Hydrogen Concentration Sampling of Isolated Gaseous Waste Decay Tank 1 Annual Emergency Drill The annual emergency drill exercise was held on April 2 and 3, 1986, with Federal, State and County participatio The drill appeared to be well conducted and no violations or deviations were identifie The drill and NRC participation will be discussed in Report No. 86-12.