IR 05000269/1995020
| ML15118A041 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 11/01/1995 |
| From: | Crlenjak R, Harmon P NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML15118A040 | List: |
| References | |
| 50-269-95-20, 50-270-95-20, 50-287-95-20, NUDOCS 9511140330 | |
| Download: ML15118A041 (13) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTA STREET, N.W., SUITE 2900 ATLANTA, GEORGIA 30323-0199 Report Nos.:
50-269/95-20, 50-270/95-20 and 50-287/95-20 Licensee:
Duke Power Company 422 South Church Street Charlotte, NC 28242-0001 Docket Nos.:
50-269, 50-270 and 50-287 License Nos.:
DPR-38, DPR-47 and DPR-55 Facility Name: Oconee Units 1, 2 and 3 Inspection Conducted:
September 10 -
ctober 7, 1995 Inspectors:
/;
1P. t. Harmon, Senior id t Inspector D4te&Signed L. A. Keller, Resident Inspector P. G umphrey, Resident Inspector N..
algado /esident Inspector Approved by:
- Mt.\\'.
Crlpd a, ChieV Dite Signed Reactor Projects Branch 1 SUMMARY Scope:
This routine, resident inspection was conducted in the areas of plant operations, maintenance and surveillance testing, onsite engineering, and plant suppor Results:
In the operations area, a drill conducted to demonstrate that the Auxiliary Service Water system could be activated within the 40 minutes assumed in analysis was unsuccessful, paragraph A concern was identified regarding increased safety equipment unavailability due to lack of coordination of maintenance activities, paragraph Two additional examples of a previously issued violation regarding inadequate configuration control were identified, paragraph In the maintenance area, a weakness was identified in an instrument calibration procedure, paragraph 3.a(4). The licensee received an unanticipated lockout of a Keowee Hydro Unit due to inadequate procedural control ENCLOSURE 9511140330 951101 PDR ADOCK 05000269 G
In the engineering area, a weakness was identified regarding the licensee's program for correcting drawing deficiencies in that known drawing errors could exist indefinitely for safety-related drawings, paragraph In the plant support area, it was concluded that the Nuclear Safety Review Board provided effective oversight of station activities, paragraph ENCLOSURE
REPORT DETAILS Persons Contacted Licensee Employees E. Burchfield, Regulatory Compliance Manager T. Coutu, Operations Support Manager 0. Coyle, Systems Engineering Manager J. Davis, Engineering Manager W. Foster, Safety Assurance Manager J. Hampton, Vice President, Oconee Site D. Hubbard, Maintenance Superintendent C. Little, Electrical Systems/Equipment Manager
- B. Peele, Station Manager
- G. Rothenberger, Operations Superintendent
- J. Smith, Regulatory Compliance
- R. Sweigart, Work Control Superintendent Other ]icensee employees contacted included technicians, operators, mechanics, security force members, and staff engineer *Attended exit intervie Acronyms and abbreviations used throughout this report are identified in
the last paragrap.
Plant Operations (71707) General The inspectors reviewed plant operations throughout the reporting period to verify conformance with regulatory requirements, TS, and administrative control Control room logs, shift turnover records, temporary modification log, and equipment removal and restoration records were reviewed routinely. Discussions were conducted with plant operations, maintenance, chemistry, health physics, I&E, and engineering personne Activities within the control rooms were monitored on an almost daily basi Inspections were conducted on day and night shifts, during weekdays and on weekend Inspectors attended some shift changes to evaluate shift turnover performance. Actions observed were conducted as required by the licensee's Administrative Procedure The complement of licensed personnel on each shift inspected met or exceeded the requirements of T 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 During the plant tours, ongoing activities,
ENCLOSURE
- housekeeping, security, equipment status, and radiation control practices were observe Plant Status All three units operated at or near full power throughout the inspection perio CFR 50.72 Notification Regarding ASW System The ASW system was originally designed for a non-design bases event, the loss of the intake canal/structure. However, following NUREG 0737 review of the facility for tornado vulnerabilities, the system was discussed in the July 28, 1989, NRC SER as the means to mitigate the consequences of a tornado. For a severe tornado the ASW system, in conjunction with the HPI system, were required to maintain the units in a safe shutdown condition by providing decay heat removal via the steam generators and RCS makeup. ASW is a shared system common to all three units and is comprised of one 3000 gpm centrifugal pump, its'associated piping, valves and switchgear. The water supply for the ASW system is lake water from the Unit 2 CCW pumps' discharge piping. The ASW pump is manually started at the ASW Switchgear Panel (basement level of Auxiliary Building).
The only other actions necessary in the severe tornado event was operation of a HPI pum Since normal HPI pump power was not tornado protected, one HPI pump motor per unit could be manually connected to the ASW Switchgear through spare power cables staged for this purpose. To support the licensee submittal that ultimately led to the tornado SER, Calculation OSC-2262, Tornado Protection Analysis, was generate The calculation indicated that the ASW system must be put into operation within 40 minutes to prevent core uncover In a previous inspection IFI 50-269,270,287/93-25-06 identified that no test or drill had been devised to confirm the operator's ability to place ASW in operation within 40 minutes. On September 19, 1995, the licensee conducted an emergency drill which was designed in part to test the ability to mitigate a tornado that disables all HPI, as well as main and emergency feedwater. During this drill it took the licensee approximately 54 minutes to place ASW and HPI in operation. The majority of this time was consumed in exhausting all other possible sources of feeding the steam generators. The licensee made a four-hour non-emergency call under 10 CFR 50.72(b)2(iii)(B) "remove residual heat" to report this drill failur PIP 0-095-1192 was initiated to disposition the drill failur The licensee's evaluation concluded that the drill failure was in large part due to drill message sheets not accurately describing the extent of damage from the tornado. The licensee concluded ENCLOSURE
that following an actual tornado the operators could easily determine the necessity of using the ASW system when the extent of damage actually existed that would require ASW. Based on this conclusion, the licensee retracted the 10 CFR 50.72 notificatio The licensee intends to conduct another drill before the end of 199 The inspectors concluded that the licensee's evaluation was adequate and that it was reasonable for ASW to be placed into operation within 40'minute The inspectors further concluded that the decision to retract the 10 CFR 50.72 was adequately supported by their evaluation. However, the inspectors continue to believe that the licensee needs to successfully demonstrate this capability. This matter will continue to be tracked under IFI 269,270,287/93-25-06. Actions to Improve Operator Responses to Abnormal Event Out Of Service Equipment On September 5, 1995, the inspectors noted that the "A" HPSW Pump had been taken out of service for a scheduled maintenance activity at 5:01 a.m., and Units 1 and 2 entered a 7 day LCO as required by Selected Licensee Commitment 16.9.1, Fire Suppression Water System. The inspectors later that day inquired about the progress of the pump maintenance and learned that the effort had been rescheduled for a later date because of problems associated with planning the wor After approximately 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> of being out of service, the "A" HPSW Pump was returned to service and the LCO was exited at 11:55 On September 25, 1995, the inspectors again noted that Unit 1 was in an LCO for 14 hours1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br /> because the 1A BS Pump was out of service for a lubrication PM on the pump and motor, as well as to perform mechanical and electrical PMs on valve 1BS-The inspectors had monitored the activity because the PM on the valve could have been performed during the refueling outage, which would limit the time that the unit was in an LCO. However, the licensee contended that the valve work would not extend the LCO time that the system would be out of service for pump and motor lubrication. That conclusion supported a decision to perform the maintenance activity while on line, since the net unavailability of the BS system would not be increased by adding the valve work to the pump outage windo The inspector reviewed two previous lubrication activities performed in December 1994, and learned that the equipment had been out of service for less than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for each activit The licensee explained that the work on September 25, 1995, could have been done within the same time frame, but problems were experienced in coordination and testing of the valv *
ENCLOSURE
Il
The issue of having safety equipment out of service unnecessarily (in the case of the "A" HPSW Pump) and for longer periods than required (in the case of the 1A BS Pump) was discussed with plant management. In addition, plant management was reminded of a similar event that was documented in NRC IR 50-269,270,287/95-02, Paragraph 3.a.(9), where the lA Low Pressure Service Water Pump was taken out of service for more than 52 hours6.018519e-4 days <br />0.0144 hours <br />8.597884e-5 weeks <br />1.9786e-5 months <br /> prior to beginning the scheduled wor Although licensing requirements were not violated, the inspectors concluded that better coordination should have been emphasized prior to taking the equipment out of service, thereby minimizing LCO time periods. The licensee agreed to review the circumstances surrounding the two event Configuration Control On September 19, 1995, two NLOs were in the process of tagging out the Auxiliary Service Water Pump Breaker. The NLOs mistakenly pulled the fuse blocks and opened the Auxiliary Service Water Switchgear.Transformer Feeder Breaker as opposed to the specified Auxiliary Service Water Pump Breaker. Prior to locating the crank to rack the breaker out, one of the NLOs noticed a breaker with the correct label and realized that the wrong breaker had been opened and tagged. The activity was stopped and the control room SRO was informed. This is an additional example of previously cited Violation 50-269,270,287/95-18-01, Inadequate Configuration Contro On October 1, 1995, an NLO tripped the wrong relay while performing PT/O/A/610/5B, Electro-Mechanical Relay Breaker Trip Test. Enclosure 12.22, Step 22 of the performance test specified that relay 51TN AUTOBANK TERT. be tripped. However, relay 51TN BANK 5T was tripped instead, resulting in the loss of alternate power to the station services electrical bus This is an additional example of previously cited Violation 50-269,270,287/95-18-01, Inadequate Configuration Contro In both instances, the errors were immediately discovered and corrective actions were initiated. The licensee reported the events and documented each in their PIP program to require a formal review and analysis, as well as to specify corrective actions to prevent recurrenc Within the areas reviewed, a drill conducted to demonstrate that the ASW system could be activated within the 40 minutes assumed in analysis was unsuccessful, paragraph 2.c. A concern was identified regarding increased safety related unavailability due to lack of coordination of ENCLOSURE
maintenance activities, paragraph 2.d. Two additional examples of a previously issued violation regarding inadequate configuration control were identified, paragraph.
Maintenance and Surveillance Testing (62703 and 61726) Maintenance activities were observed and/or reviewed during the reporting period to verify that work was performed by qualified personnel and that approved procedures adequately described work that was not within the skill of the craft. Activities, procedures and work orders were examined to verify that proper authorization and clearance to begin work was given, cleanliness was maintained, exposure was controlled, equipment was properly returned to service, and LCOs were me Maintenance activities observed or reviewed in whole or in part are as follows:
(1) Check/Calibrate Emergency Feedwater Pressure Switches PIP 95-0127, WO 95073023 The inspector observed activities in progress during the calibration of the Unit 1 MDEFWP initiation pressure switches and cooling water valves. The effort was performed on September 26, 1995, and was in accordance with IP/0 0/0275/0051, Emergency Feedwater System Motor Driven Emergency Feedwater Pump Safety Related Instrumentation Calibration And System Functional Check, and IP/0 0/0275/006C, Safety Related Functional Test Of The MDEFWP Initiation Pressure Switches And Cooling Water Valves. The inspector reviewed the documentation and witnessed portions of the calibration procedure. The pressure switches were found to be within tolerance and the effort was performed to acceptable standard (2) Perform PM, 12 Cylinder Diesel Engine, WO 95074368 and Perform PM, 16 Cylinder Diesel Engine, WO 95074366 On October 2, 1995, the inspector observed preventive maintenance activities on both SSF diesel engines that power the SSF generator. The work was performed in accordance with procedure MP/0/A/5050/017, Diesels-SSF-Operational Inspection and Checks, and cleanliness levels were maintained in accordance with Enclosure 4, Cleanliness Level Requirement. PT/0/A/0400/11, SSF Diesel Generator Test, was performed after completion of the maintenance activities to demonstrate operability of the unit. The work was performed according to the procedure and to acceptable standard ENCLOSURE
(3) Unit 2 ES Analog Channel "C" Online Test, WO 95069730 The inspector reviewed activities in progress during the performance of IP/O/A/0310/0140, Engineered Safeguards Analog Channel "C" Online Calibration. The calibration involved channel "C" reactor coolant and reactor building pressure instruments. The effort was performed per the procedure and to acceptable quality standard (4) Keowee Unit 2 Governor Oil System Pressure and Level Instrument Calibration, WO 95064271 On September 25, 1995, the inspector observed calibration activities being conducted under IP/1/A/0400/034, Governor Oil System Pressure And Level Instrument Calibratio During this activity Keowee Unit 2 received an unexpected
"normal" lockout and several unexpected alarms. A normal lockout prevents generation to the grid but is bypassed during an emergency start. The inspector, together with the licensee system engineer, determined that the cause of the lockout was the inadvertent actuation of a low governor oil pressure switch which is designed to actuate at 290 psi decreasing. The technicians inadvertently dropped pressure below 290 psi when lowering the oil tank level to clear a high level alarm per the procedure. The inspector noted that the technicians were following their procedure, but the procedure did not provide any warnings or restrictions on how far they could lower level/pressure. While there is not an emergency lockout associated with governor oil pressure or level, there is a point where the unit can be rendered inoperable due to lack of hydraulic pressure to operate the turbine wicket gates. The licensee does not know the exact pressure below which the unit becomes inoperable, but agrees that there is a point below which operability is affected and that this point is somewhere below 280 psi (setpoint for emergency governor oil pump actuation). The inspector determined that pressure probably did not drop below 280 psi during this activity since the emergency governor oil pump did not actuat The licensee had not anticipated that this calibration activity could potentially challenge the operability of the unit and therefore performed the activity online. The inspector concluded that given the nature of the work involved and the potential risk to unit operability, this work should have been done with the unit out of service or with clear procedural barriers in place. The inspector ENCLOSURE
concluded that the licensee had not fully assessed the risks involved with this activity, and consequently did not provide adequate procedural guidance to the maintenance personnel. This oversight resulted in a weakness in the procedure. The licensee revised the procedure to prevent recurrenc The inspectors observed surveillance activities to ensure they were conducted with approved procedures and in accordance with site directives. The inspectors reviewed surveillance performance, as well as system alignments and restorations. The inspectors assessed the licensee's disposition of any discrepancies which were identified during the surveillanc Surveillance activities observed or reviewed in whole or in part are as follows:
(1) High Pressure Injection Pump Test, PT/1/A/0202/11 The inspectors observed activities in progress during the performance testing of the Unit 1, "A" and "B" HPI pump The test further included stroking the associated valves and verified that the pump discharge check valves closed when required. The results met the acceptance criteria and the performance of the test met acceptable standard (2) SSF Diesel Engine Service Water Pump Test, PT/O/A/0400/04 On October 3, 1995, the inspector witnessed the subject test. The inspector verified that equipment was properly tagged out, test equipment was properly calibrated, the test procedure was followed, and all measured parameters were within the acceptance criteria. All activities observed were satisfactor (3) Keowee Hydro Operation, PT/O/A/0620/09 On September 19, 1995, the inspector observed the subject test from the Oconee control room. This test demonstrated the operability of both Keowee units through both the underground and overhead paths. The inspector observed that the test procedure was followed and verified that all acceptance criteria were me Within the areas reviewed, a weakness was identified in a calibration procedure, paragraph 3.a(4).
All other activities observed were satisfactor ENCLOSURE
8 Onsite Engineering (37551)
During the inspection period, the inspectors assessed the effectiveness of the onsite design and engineering processes by reviewing engineering evaluations, operability determinations, modification packages and other areas involving the Engineering Departmen Resolution of Drawing Discrepancies NRC IR 50-269,270,287/95-18 documented problems with the attempted implementation of NSM 52966 which, if successfully implemented, would have resulted.in the ability to simultaneously generate both Keowee units to the grid. One of the problems encountered was a discrepancy between a connection diagram drawing (K-712-E) and the as-built configuration. This discrepancy contributed to the time delays that resulted in exceeding the LCO. The inspectors later learned that the drawing discrepancy in question had previously been identified during a Keowee drawing verification effort conducted August 31, 199 The inspectors were concerned that a drawing discrepancy for a safety-related drawing remained uncorrected for greater than two year During this inspection period the inspectors reviewed the licensee's program for correcting drawing discrepancies. There were two different mechanisms for correcting drawings; editorial minor modification or editorial change. The editorial minor modification process required the drawing to be corrected within 2 days for a VTO drawing and 60 days for a non-VTO drawing. The editorial change process did not have any time requirements/limits for correcting the drawing error. The editorial change process was intended for minor drawing discrepancies while the editorial minor modification process was intended for more significant errors. The inspectors noted that there was no clear guidance or criteria on what constituted a minor error. Furthermore, part of the decision process on whether an editorial change or editorial minor modification was required depended on whether the drawing in question was the only drawing available. Therefore, if there was an accurate drawing available which presented the proper configuration or information, the drawing error could be handled via the editorial change process. For example, a connection diagram error could be tolerated as long as a companion panel print showed the proper configuratio The inspectors noted that the editorial change process did not require any kind of stamp or warning placed on the drawing to alert potential users to the error(s) or to direct personnel to the accurate drawing. The inspectors concluded that allowing drawing errors to exist indefinitely without a mechanism to prevent personnel from using the erroneous information was a weakness in the licensee's drawing control progra ENCLOSURE
In response to the inspectors' concerns the licensee reviewed their program for correcting drawing discrepancies and compared it to the Catawba and McGuire Nuclear Station programs. The licensee discovered that the other nuclear stations do not utilize the editorial change process and process all drawing errors under the editorial minor modification program. As a result, the licensee decided to eliminate the editorial change program at Oconee as wel The inspectors concluded that eliminating the editorial change program and handling all drawing errors under the editorial minor modification program would eliminate the inspectors'
concern Main Feedwater Pump Discharge Pressure Switch Setpoint Change LER 269/94-06 identified a problem with excessive drift affecting pressure switches that monitor low MFDWP discharge pressure and provide inputs to the RPS trip signal and EFW initiation. As a result of this problem the licensee had to perform bi-weekly calibrations to ensure that switch drift did not exceed its setpoint margins. Minor Modification OE-8515 changed the MFDWP discharge pressure setpoint for the RPS and EFW related pressure switches from 770 psi to 800 psi decreasing. This reversed a previous minor modification that changed the setpoint from 800 to 770 ps This latest change was performed to increase the margin between the "D" Heater Drain Pump discharge pressure and the pressure switches in question. By increasing the margin, the licensee was able to extend the calibration frequency from bi weekly to semiannually. This will substantially decrease EFW unavailability due to maintenance. The increase in setpoint will marginally increase the risk of a spurious trip during feedwater transients. The licensee concluded that this risk was minor compared to the benefit of reducing EFW system unavailabilit The inspectors reviewed the minor modification package and the 10 CFR 50.59 evaluation associated with this setpoint change and found them to be acceptabl Within the areas reviewed, a weakness was identified regarding the licensee's program for correcting drawing discrepancies. The licensee subsequently corrected the weakness, paragraph.
Plant Support (71750 and 40500)
The inspectors assessed selected activities of licensee programs to ensure conformance with facility policies and regulatory requirement During the inspection period, the following areas were reviewed:
On September 20 and 21, 1995, the inspectors attended the NSRB meeting with the licensee which consisted of a review of ONS operational activities and design aspects of the station. Although the NSRB had identified no significant nuclear safety issues affecting the continued ENCLOSURE
operation of ONS, some areas of concern were identified along with strengths and weaknesse The NSRB reviews focused on issues important to safety and addressed other areas where the licensee could make improvement Within the areas reviewed, licensee activities were satisfactor.
Exit Interview The inspection scope and findings were summarized on October 12, 1995, with those persons indicated in paragraph I above. The inspectors described the areas inspected and discussed in detail the inspection findings addressed in the Summary and listed below. No dissenting comments were received from the licensee. The licensee did not identify as proprietary any of the material provided to or reviewed by the inspectors during this inspectio Item Number Status Description/Reference Paragraph IFI 269,270,287/
Open Actions to Improve Operator 93-25-06 Responses to Abnormal Events, paragraph.
Acronyms ASW Auxiliary Service Water BS Building Spray CFR Code of Federal Regulations CCW Condenser Circulating Water EFW Emergency Feedwater ES Engineered Safeguards GPM Gallons Per Minute HPI High Pressure Injection HPSW High Pressure Service Water IFI Inspector Followup Item I&E Instrument & Electrical IR
Inspection Report
LER
Licensee Event Report
LCO
Limiting Condition for Operation
MFDWP
Main Feedwater Pump
MDEFWP
Motor Driven Emergency Feedwater Pump
Maintenance Procedure
Non Licensed Operator
NSM
Nuclear Station Modification
Nuclear Safety Review Board
Oconee Nuclear station
Pounds per Square Inch
Problem Investigation Process
Preventive Maintenance
ENCLOSURE
Performance Test
Safety Evaluation Report
Senior Reactor Operator
SSF
Standby Shutdown Facility
TS
Technical Specification
VTO
Vital To Operations
Work Order
ENCLOSURE