IR 05000341/1998003
ML20216C875 | |
Person / Time | |
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Site: | Fermi ![]() |
Issue date: | 05/11/1998 |
From: | Burgess B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
To: | |
Shared Package | |
ML20216C821 | List: |
References | |
50-341-98-03, 50-341-98-3, NUDOCS 9805190428 | |
Download: ML20216C875 (24) | |
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U.S. NUCLEAR REGULATORY COMMISSION REGION lit Docket No: 50-341 License No: NPF-43 Report No: 50-341/98003(DRP)
Licensee: Detroit Edison Company Facility: Enrico Fermi, Unit 2 Location: 6400 N. Dixie Hw Newport, MI 48166 Dates: December 21,1997 - March 16,1998 Inspectors: G. Harris, Sec.ior Resident inspector C. O'Keefe, Resident inspector Approved by: Bruce Burgess, Chief Reactor Projects Branch 6
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l 9805190428 980511 PDR ADOCK 05000341 G PDR ;
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I EXECUTIVE SUMMARY Enrico Fermi, Unit 2 NRC Inspection Report No. 50-341/98003(DRP)
This inspection included aspects of licensee operations, engineering, maintenance, and plant support. The report covers a nine-week period of resident inspectio Oovrations e Operator response to a reactor scram caused by a main turbine trip was conducted in a l controlled and coordinated manner. Shift supervisc,y personnel provided clear, i conservative direction. Support orGr.nizations' efforts were coordinated. In general, plant equipment response was good. (Section O1.1)
e Operators responded to an inadvertent load shed of Safety Bus 72E in a coordinated and
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methodical manner. Shift supervision provided clear direction to operators and support personnel responding to the event. Support personnel, including a crew of operators from training, were effectively utilized. Notification of the event to the NRC, Technical Specification actions, and documentation of events were appropriate and complete. (Section 01.2)
e Two examples of a deviation from a commitment to comply with Regulatory Guide 1.78,
" Control Room Habitability," were identified. The licensee's practices regarding availability of backup respirators in the control room and training on toxic chemical j recognition and prompt donning of respirators for operators, did not comply with the l Regulatory Guide. Additionally, two issues affecting the ability to respond adequately to a chlorine release were identified. (Section 08.1)
Maintenance e The licensee effectively addressed emergent equipment problems identified during the forced outage and the subsequent plant startup. A good questioning attitude was demonstrated during the replacement of the control room chlorine detector, but _
l inadequate preparation for the work resulted in the inability to complete the job after i l entering a limiting condition for operation. A motor-operated potentiometer was not I properly adjusted prior to installation, resulting in a challenge to the emergency diesel L generator and delays in retuming it to service. (Section M1.1) ;
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e Plant management discussed three instances of potential preconditioning, identified by the NRC and licensee personnel, with plant staff to further sensitize personnel to potential preconditioning issues during maintenance and testing. The licensee intended to evaluate the response to specific issues after creation of a station policy on the subject l based on industry and regulatory practices in this area. A systematic review of ,
maintenance and testing practices against this policy was also planned. (Section M1.2) l
- Residual Heat Removal Pump B developed multiple indications of unusual wear. The I inspectors expressed concem about the pump's long term operability when the licensee l
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evaluated the motor as acceptable. Subsequently, the decision was made to replace the motor. (Section M2.1)
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- The inspectors coricluded that the licensee's failure to provide adequate instructions to ensure proper configuration control of switchyard electrical components resulted in the installation of a protective relaying circuit card with an improper configuratio Switchyard configuration control was assigned to an offsite organization, which did not use the station's configuration control program. The licensee's corrective actions were comprehensive, including an extensive verification of switchyard component configuration. (Section M3.1)
e An inadvertent load shed on Safety Bus 72E was caused by an unclear surveillance test
, procedure step. Inadequate reviews of the procedure revision and a lack of questioning attitude by maintenance workers contributed to the event. A violation was identified for an inadequate procedure. The licensee's investigation was prompt and thoroug ,
(Section M3.2) l l e The inspectors identified that maintenance personnel incorrectly concluded that as-found l relay timing data for an alarm circuit associated with the scram discharge instrument l volume could be copied from a previously performed test. The relay was replaced as part
[ of regularly scheduled preventive maintenance. The old relay was successfully tested 4
- after the inspectors questioned the lack of as-found testing. The omission was caused by l
a confusing work package step. (Section M3.3) ,
l Endneerina l e The inspectors concluded that the licensee acted in a conservative manner and declared l both systems of low pressure coolant injection inoperable when it was discovered that manual ope mor action was required for proper low pressure coolant injection actuation.
, The conditions resulted in some complications in the conduct of surveillance testing.
l (Section E2.1)
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e The inspectors concluded that slow turbine valve stroke times, which caused higher than
, design turbine speeds during a load rejection, were the result of corrosion products
! found in the EHC system from in leakage in the turbine hydraulic oil coolers. This condition went unnoticed for a longer period of time because of the reduced frequency of valve testing . The inspectors were concemed with the corrective actions to apply a graphite lubrication in a high temperature and moist environment, since that lubricant l
would lose its effectiveness over time in that environment. (Section E2.2)
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- The licensee appropriately conducted a thorough review of all inputs to and calculations 1 l used to support the core thermal power computation. No other errors were identified. A !
l non-cited violation was identified for having exceeded the licensed core thermal power at i one or more times in the past by a small fraction of a percent. (Section E8.1)
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Plant Support e No significant issues in the plant support functional area were identifie _ ..
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Report Details Summary of Plant Status Unit 2 began this inspection period at 96 percent power. On February 1, the plant tripped as a result of a main turbine trip caused by a spurious protective circuitry initiation in the 345kV switchyard. The unit was retumed to 96 percent power on February 15, and remained at that power for the rest of the inspection period.
l 1. Operations .
l l 0 Conduct of Operations
01.1 Operator Response to a Plant Trio l Inspection Scope (93702)
The inspectors responded to the site following notification of a plant trip on February The inspectors observed operator iesponse to the event, reviewed control room logs and sequence of events recorder printouts, and walked down control room recorders and panel indications. Plant equipment performance was evaluated based on available information and discussions with ge<cto@ Findinas and Observations On Febmary 1, the reactor tripped from 96 percent power. The reactor scram was initiated from a main turbine trip caused by the actuation of breaker failure protective circuitry in the 345 kV switchyard. Offsite power to the plant was not interrupted during
, this event. The inspectors verified that all control rods fully inserted.
Reactor water level was controlled, and no injection was required from emergency core cooling or engineered safety feature systems, due to prompt operator response to the trip. All plant equipment responded as required. The inspectors observed that operator response to the event was good. Procedures were appropriately entered and followe The response to the event was well coordinated by the Nuclear Shift Supervisor (NSS)
and the Nuclear Assistant Shift Supervisor (NASS), who prioritized operator actions and provided clear direction. A prompt notification to the NRC Operations Center, required by
!' 10 CFR 50.72(b)(2)iii, was made within the required tim ,
The cause of this evert is discussed in Section M Conclusions Operator response to a reactor scram caused by a main turbine trip was conducted in a
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controlled and coordinated manner. Shift supervisory personnel provided clear, conservative direction. Support organization efforts were coordinated. In general, plant ( equipment response was goo i
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O1.2 Operator Response to inadvertent Load Shed of Safety Bus Inspection Scope (93702)
On February 20, electricians inadvertently caused an automatic load shed of 480V Engineered Safeguard System Bus 72E when the wrong cutout switch was opened during surveillance testing of safety circuits. The inspectors responded to the control room to observe operator response. Technical Specification (TS) actions and notifications were checked against requirements. Procedure usage, communication practices, and documentation of events were reviewe Findinas and Observations Electricians were performing Surveillance Test 42.302.03, " Channel Functional Test of Division 2 4160 Volt Bus 65E Undervoltage Circuits," when numerous loads powered from Bus 72E were unexpectedly deenergized. When the electrician heard the breakers trip, the control room was immediately notified. Control room operators promptly evaluated which equipment was deenergized and recognized the cause was an actuation of the load shed circuitry. The NSS and NASS effectively prioritized restoration of equipment and mobilized support personne The NASS called all available operators to the control room for a briefing and task assignments. A crew of operators in training was called to assist. This resulted in a deliberate and coordinated response to the event. Control room operators were obr".ad effectively documenting limiting conditions for operations (LCO) entries, equipment lost and restored, and the basis for significant decisions. Procedure use was obcarved to be excellent, despite the large number of procedures required during this event. The inspectors observed that shift supervision provided clear direction to operators and j numerous support personnel throughout the recover The cause of the event was promptly identified by the event investigation team. An I
equipment restoration lineup verification was created by engineering, operations and maintensnce personnel and approved by operations supervision before the bus and j deenergized loads were restore The inspectors reviewed log entries and determined that all of the numerous required TS actions were completed and documented. A prompt notification to the NRC Operations Center required by 10 CFR 50.72(b)(2)(ii) was made within the required time. This event is further discussed in Section M Conclusions Operators responded to an inadvertent load shed of Safety Bus 72E in a coordinated and methodical manner. Shift supervision provided clear direction to operators and support personnel responding to the event. Support personnel, including a crew of operators from training, were effectively utilized. Notification of the event to the NRC, TS actions, i and documentation of events were appropriate and complet .
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01.3 Reactivity Manipulation Error Promptly identified On February 2, the licensee began replacing a nuniber of control rod scram solenoid pilot valves. The work wss conducted on two control rods at a time, and required that the -
!. associated control rods be fully inserted during the work. Wnen each pair was done, operators performed individual scram time testing as post-maintenance testing (PMT).
After briefing the evolution for the first pair of control rods, on February 23, operators successfully withdrew and tested the first control rod (18-59). However, the licensed operator performing reactivity manipulation failed to select the next rod (26-59) before starting to withdraw what was thought to be the second rod for testing. With Rod 18-59 t
still selected, the operator started to withdraw the rod without notifying the reactor
! engineer or NASS observing the reactivity manipulations. The NASS recognized the error and ordered rod motion stopped. The rod was withdrawn a single notch. The licensee conducted a prompt investigation, which concluded that the operator had not properly communicated his intended actions such that the personnel verifying the correctness of l reactivity manipulations were unable to prevent the erro The inspectors confirmed, by reviewing computer printouts, the licensee's conclusion that l this had no effect on power or thermal limits of the core. Thus, there was no safety l significance to this event. The inspectors determined that licensee procedures were not l tiolated, although the operations department policy on reactivity manipulation verifications was clearly not met. The inspectors concluded that the NASS was effective in promptly identifying the error.
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{ 02 Operational Status of Facilities and Equipment O Enaineered Safety Feature System Walkdowns (71707)
The inspectors used Inspection Procedure 71707 to walk down accessible portions of the following engineered safety feature system e Division 2 Core Spray System o High Pressure Coolant Injection System e Reactor Core isolation Cooling System e Reactor Protection Electrical Power System o Standby Liquid Centrol System l~
o Standby Feedwater System
- e Emergency Equipment Cooling Water System l e Emergency Diesel Generator Nos.11 and 14 l- e 130/260V Batteries and Chargers
!- e Control Center Heating, Ventilation and Air Conditioning System e Standby Gas Treatment System Equipment operability, material condition, and housekeeping were acceptable in all i cases. Several minor discrepancies were brought to the licensee's attention and were corrected. The inspectors did not identify any substantive concerns as a result of these walkdown l l
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08 Miscellaneous Operations issues (92700)
08.1 (Closed) Inspection Followup item 50-341/97013-07: Lack of training and procedural direction for the use of air masks in the control room. The Fermi 2 Updated Final Safety Analysis Report (UFSAR), Appendix A, committed the licensee to compliance with Regulatory Guide (RG) 1.78. The inspectors identified that the licensee did not appear to be meeting a commitment to RG 1.78 in the following respects:
l l e Regulatory Position C.13 of RG 1.78, stated that each operator should be taught to distinguish the smells of hazardous chemicals peculiar to the area. Instruction should include a periodic refresher course. Practice drills should be conducted to ensure that personnel can don breathing apparatus within two minutes. The inspectors determined that training provided to operators did not include distinguishing the smells of hazardous chemicals, nor were practice drills conducted to ensure that operators were able to don masks promptly. Condition Assessment Resolution Document (CARD) 98-11975 was written to initiate ;
l corrective actions for this issue. This was considered to be an example of a 1 deviation from a regulatory commitmen e Regulatory Position C.14 stated, in part, that air supply equipment should meet the single-failure criterion. For self-contained breathing apparatus, this may be accomplished by supplying one extra unit for every three units required. The inspectors determined that five mask units were available in the control room for the five operators that were required continuously in the control room. The closest available replacements were outside the control room a short distance away. This was not considered to meet the intent of the single failure criterion because in the event the masks were needed, one operator would have to leave
- the control room to obtain extra units. This was considered to be another example of a deviation from a regulatory commitment. (DEV)(50-341/98003-01)
Additionally, Regulatory Position C.15 t ated that emergency procedures for hazardous chemical release within or near the station should discuss the methods for detecting the i
event. This Regulatory Position also stated that specialinstrumentation provided for the detection of chemical releases should be described. The inspectors determined that the l only instruments capable of detecting chlorine on the Fermi site were the two detectors l installed in the control center heating, ventilation and air conditioning system (CCHVAC)
l inlet duct. The inspectors noted that the inlet included a long vertical drop to the chlorine detectors which would trap the heavier-than-air chlorine gas when it tripped shut the inlet dampers upon detection. Without a means of removal, operators would be unable to i reestablish a normal CCHVAC lineup without allowing the trapped chlorine to enter the control room. Also, the only available chlorine detectors would be useless to determine the condition of the atmosphere where the operators would be located, requiring continued use of breathing masks. The results of the licensee evaluation of the potential l CCHVAC design deficiency and lack of pcriable cNorine detection equipment will be
! reviewed to determine if an additional deviation from commitments exists. This is considered an inspection followup item. (IFl 50-3461/98003-02)
The inspector also identified that two senior reactor operators had license restrictions that specified that they may not wear respirators. This appeared to prevent them from standing a watch which required their continuous presence in the control room, yet no
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stipulation on watch scheduling had been made by the licensee to ensure that these individuallicense restrictions were met. This will be treated as an inspection followup item pending NRC review of licensee corrective actions for this issu (IFl 50-341/98003-03)A deviation with two examples from a commitment to comply with Regulatory Guide 1.78, " Control Room Habitability," was identified. The licensee's practices regarding availability of backup respirators in the control room, and training on toxic chemical recognition and prompt denning of respirators for operators did not comply with the Regulatory Guide. Additionally, two issues affecting the ability to respond adequately to a chlorina release were ideWfie Two examples of a deviation from a commitment to comply with Regulatory Guide 1.78,
" Control Room Habitability," were identified. The licensee's practices regarding availability of backup respirators in the control room, and training on toxic chemical recognition and prompt donning of respirators for operators did not comply with the Regulatory Guide. Additionally, two issues affecting the ability to respond adequately to a chlorine release were identifie .2 (Closed) Violation 50-341/97002-02: Lack of required procedures for operation of offsite power system. The licensee created new Procedures 23.301.01, "120kV Bus Operation,"
and 23.301.02, 345kV Bus Operation," for the required operations for both switchyard The inspectors noted that the new procedures did not cover all switchyard equipment or all routine operations. However, the procedures did meet the requirements of Regulatory Guide 1.33. This item is close .3 (Closedi LER 341/97007-00: Failure of Reactor Building ventilation during shutdown conditions, resulting in the brief loss of secondary containment integrity. Corrective actions included starting the reactor building exhaust and inlet fans to restore secondary containment integrity, and replacement of a failed solenoid. Solenoids in other systems were visually inspected to determine if they were susceptible to a similar failure. This LER was a minor issue and was close II. Maintenance M1 Conduct of Maintenance M1.1 General Comments Inspection Scope (62707)
The inspectors observed all or portions of the following work activities:
- High Pressure Coolant Injection Pump and Valve Operability Surveillance o Scram Discharge Instrument Volume Level Switch Calibration e Scram Discharge Volume Vent and Drain Valve Surveillance e Scram Solenoid Pilot Valve Replacements
- Control Rod Scram Time Testing e Emergency Diesel Generator (EDG) No.14 Slow Start Surveillance
- Standby Feedwater System Motor-Operated Valve inspections e Reactor Building Stationary Particulate lodine Noble Gases Monitor Pump Replacement
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l e Main Steam Line Isolation Channel Functional Test I
e Drywell Suppression Chamber Vacuum Breaker Operability Test e Channel Functional Test of Division 14160 Volt Bus 64C at BUS 12EB Undervoltage Circuits e Radiological Effluent Weekly Surveillance - Reactor Building e Radiological Effluent Weekly Surveillance - Turbine Building
- Radiological Effluent Weekly Surveillance - Radwaste
! * Radiological Effluent Weekly Surveillance - Standby Gas Treatment System l Division 1 l e Division 2 Standby Gas Treatment System Filter and Secondary isolation Damper l Operability Test l e Emergency Core Cooling System - Automatic Depressurization System Primary Containment Pneumatic Supply System Low Alarm Functional Test e Average Power Range Monitor Calibration e Anticipated Transient Without Scram Low Set Reactor Vessel Pressure Division 1
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b. Findinas and Observations No significant deficiencies were identified during the performance of these activitie The inspectors noted that the licensee was challenged with several emergent j
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maintenance issues during the forced outage. For example, work was performed on a residual heat removal (RHR)/ Low pressure coolant injection (LPCI) testable check valve to repair a leak inside the drywell. A seal on the actuator assembly was determined to be leaking. The inspectors observed that repairs to the check valve were prompt and error ,
fre I i During a surveillance for EDG No.12, the motor-operated potentiometer failed to control j
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speed of the engine, resulting in a higher than expected frequency requiring operator action to correct. The licensee's investigation revealed that some micro switches were loose and the motor-operated potentiometer required replacement. The licensee utilized vendor expertise to troubleshoot and correct the problem. The inspectors noted that the diesel was unnecessarily started and tested and delays in returning the diesel to service were encountered due to incorrect initial settings for the new motor-operated potentiometer (MOP). The inspectors observed the TS required testing of other EDGs to ensure no common mode failure existed. No other deficiencies were identifie Several leaks were identified during plant startup. One significant leak was associated with an orifice flange for flow instrumentation fcr the heater drain pumps. The inspectors j reviewed the licensee's plan for repair of the leak. The repair plan included the injection I of a sealant compound. The inspectors reviewed the applicable station procedure and
! noted that the licensee complied with requirements for use of the sealant compoun ,
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l Workers were attempting to replace the Division 2 Control Center Heating, Ventilation j l and Air Conditioning (CCHVAC) system chlorine detector for preventive maintenance, i l Attempts to calibrate all four spare detectors failed. The workers then identified that the i calibration reference gas was 3.8 ppm chlorine instead of the required 5.0 ppm. A record review revealed that there was no impact on the operability of installed equipment. The i original detector was reinstalled until a working spare detector could be procured. An l
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investigelion was conducted as to why the spare part bench test and the calibration gas control process had not identified the problems before entering a limiting condition for l operation (LCO) for this wor Workers also identified a procedure deficiency involving a gain adjustment in Calibration Procedure 44.140.004, Revision 30, "CCHVAC Chlorine Detector Division 2 Channel l Calibration / Functional." Workers displayed a good questioning attitude in investigating
! this problem and bringing it to resolutio Conclusions i The licensee effectively addressed emergent equipment problems identified during the l forced outage and the subsequent plant stariup. A good questioning attitude was <
demonstrated during the replacement of the contro! room chlorine detector, but inadequate preparation for the work resulted in the inability to complete the job after entering an LCO A MOP was not property adjusted prior to installation, resulting in a challenge to the EDG and delays in retuming it to servic M1.2 Potential Preconditionina Issues identified ? Inspection Scope (62707)
Three instances of potential preconditioning due to maintenance and testing practices were identified. The inspectors discussed these maintenance and testing practices with system engineers and inservice testing engineers, reviewed work history for the components and systems of concem, and reviewed NRC Information Notice 96-16, "BWR j
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Operation With Indicated Flow Less Than Natural Circulation." ,
, Findinas and Observations l
l On January 9, Scram Discharge Vent Valve C1100-F010, initially failed to stroke during testing. While reviewing Surveillance Test Procedure 24.106.004, " Scram Discharge Volume Vent and Drain Valve Operability Test," the inspectors noted that the test sequence potentially preconditioned all but the first valve tested. The inspectors noted that all four valves (two vent valves in series; two drain valves in series) stroked simultaneously in response to a single control signal, but only one valve was timed during each test. This necessitated four consecutive valve cycles in order to test all valves. The
- licensee agreed with the inspectors observation and concluded that this was potentially preconditioning three of the four valves. The inspectors reviewed the maintenance history for the four valves and identified that only the first valve timed (C1100-F010) had !
ever been identified to have slow stroke time !
On January 13, the inspectors identified that potential preconditioning occurred during the j quarterly high pressure coolant injection (HPCI) pump and valve operability surveillance j test. Specifically, some valves were stroke timed before or after the system test. Some valves were tested after they were cycled one or more times. This appeared to be caused by the licensee's practice of combining inservice testing requiring valve timing tests with a TS required system performance tes I l .
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Also on January 13, operators questioned the practice of scheduling preventive maintenance to lubricate HPCI system valves just prior to the system surveillance test !
which involved a valve stroke timing preconditioning concem. This concem was j
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documented in CARD 98-10548.
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Ir. response to these issues, the licensee formed a multi-disciplined solution team to l evaluate industry practices and regulatory positions on preconditioning. This team was assigned the responsibility to create a station policy that defined preconditioning and to identify and correct any instances of preconditioning. A systematic review of maintenance and testing practices against the new policy was planne Conclusions i
Plant management discussed three instances of potential preconditioning, identified by NR.C and licensee personnel, with plant staff to further sensitize personnel to potential preconditioning issues during maintenance and testing. The licensee intended to evaluate the response to specific issues after creation of a station policy on the subject based on industry and regulatory practices. A systematic review of maintenance and testing practices against this policy was planne M2 Maintenance and Material Condition of Facilities and Equipment M2.1 Residual Heat Removal Pump Maintenance a. Inspection Scope (62707)
The inspectors reviewed the residual heat removal (RHR) system vibration data and maintenance history, interviewed maintenance and system engineering personnel, and reviewed applicable portions of the UFSAR, Safety Evaluation Report, and T l l
b. Observations and Findinas
i The inspectors reviewed the results of ferrographic analysis of oil samples from the RHR
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System Pump B lower motor bearing. The analysis revealed a significant amount of wear particles present in the oil sample. The licensee used a Severe Wear Index indicator to determine the extent of potential wear for this component. Water and sediment readings were also slightly elevated, and vibration measurements of the bearing indicated some elevated vibration. In addition, nonlicensed operators observed that the lower bearing oil had darkened in colo Licensee procedures required further sampling and an operability evaluation due to the high severe wear index reading. The licensee concluded that the pump remained operable. The inspectors expressed concem about the long term operability of the pump to station management. A conference call was held between the office of Nuclear
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Reactor Regulation, Region ill, the resident staff, and the licensee to discuss the status of l
the pump. The licensee preliminarily concluded that the pump remained operabl However, further testing revealed unacceptably high vibrations on the pump's upper l
motor bearing. The licensee immediately shut down the pump and halted the test. The licensee decided to replace the pump motor with a newly refurbished spare. The inspectors observed work activities associated with the pump motor replacement. The
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licensee successfully tested the pump and declared the pump operable. Vibration data for the upper motor bearing was acceptable following the maintenanc Conclusions Residual Heat Removal Pump B developed multiple indications of unusual wear. The inspectors expressed concem about the pump's long term operability when the licensee evaluated the motor as acceptable. Subsequently, the decision was made to replace the i motor.
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M3 Maintenance Procedures and Documentation i l
M3.1 Switchyard Confiauration Control Problems Inspection Scope (92903)
The inspectors reviewed the UFSAR, Safety Evaluation Report, TS, and applicable drawings related to a licensee identified switchyard equipment problem. The inspectors also observed the performance of work activities, interviewed system and component ;
engineering personnel, and vendor representative j Observations and Findinas The inspectors conducted a followup inspection to review switchyard equipment concems identified by the licensee during the root cause investigation for the February 1 reactor trip. The plant trip occurred during a weekly surveillance to test an alarm function for the Brownstown B Line Protective Relaying Circuitr Investigations by the licensee ruled out operator error as a cause. Further investigation revealed that a voltage spike caused the protective relaying to sense a false fault condition and trip open three switchyard breakers, including the two generator output breakers. This was determined to have been caused by an old circuit card design which was susceptible to voltage spiking. The issue had been identified in the early 1970s and all circuit cards were believed by the licensee to have been corrected. A circuit card that l
had not been corrected had been installed in January 1997 due to personnel error and I
weaknesses in the equipment performance and predictive maintenance (EPPM) work control proces Switchyard maintenance and equipment configuration control was the responsibility of the licensee's corporate EPPM group. Licensee procedures exempted portions of the switchyard, including the affected protective relaying, from station configuration control requirements. Instead, the EPPM program was used to maintain the configuration of the component The inspectors reviewed applicable procedures and noted that the installation instructions for the card in question did not require verification or documentation of the required modifications. The inspectors determined that the EPPM work control process relied
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excessively on the technicians' knowledge of the equipment to ensure the correct circuit card configuration. The inspectors concluded that failure to provide adequate instructions to technicians performing modifications 'o switchyard electrical components resulted in
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the breaker failure relay card not being modified as intended prior to installation. This was not considered to be a violation because the quality controls of 10 CFR Part 50, Appendix B, do not apply to switchyard components.
l The licensee's immediate corrective action incluc'ed a detailed verification of component
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configuration for both switchyards onsite. No additional discrepancies were noted during this review. In addition, plant management implemented a comprehensive interim work l control policy to ensure the proper execution of maintenance and modifications for i switchyard components. Finally, a dedicated individual was identified to provide oversight of switchyard work activitie Conclusions The inspectors concluded that the licensee's failure to provide adequate instructions to ensure proper configuration control of switchyard electrical components resulted in an improper configuration in a protective relaying circuit card and contributed to a plant tri Switchyard configuration control was assigned to an offsite organization, which did not utilize Fermi's configuration control program. The licensee's corrective actions were comprehensive, including an extensive verification of switchyard component configuratio M3.2 Unclear Surveillance Test Procedure Stoo Results in load Shed of Safety Bus 72E i Inspection Scope (92902) '
The inspectors conducted a followup inspection to review the circumstances surrounding the February 20 load shed of Bus 72E. The test procedure was reviewed. The licensee's formal Human Performance Enhancement System evaluation was reviewed and discussed with the team leader for the investigation. Plant procedures and system schematics were reviewed to verify that actuations and isolations occurred as expecte Findinas and Observations A load shed of 480V Safety Bus 72E occurred when the wrong trip string cutout switch was opened. This was not recognized, so an undervoltage condition was simulated on the wrong bus, resulting in an actual load she The licensee determined that the wrong switch was opened because a recent procedure revision introduced a step that allowed the operator to select the wrong bus. Revision 31 to Surveillance Test Procedure 42.302.03, " Channel Functional Test of Division 2 4160 Volt Bus 65E Undervoltage Circuits," was made to incorporate several equipment labeling changes. The switch label had been changed a year and a half earlier, but the procedure
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had not been changed until a week before the event. The procedure change received only limited reviews because no technical changes were being made. Neither reviewer identified that the applicable step permitted the reader to select the wrong bu A pre-job brief was conducted by the Work Group Supervisor; however, it did not include a discussion of changes that had been made since the test was last performed. The workers had both performed the test before and were satisfied that they understood what was required to complete the step. When the workers realized that breakers were
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actually opened in responte to a simulated trip, they immediately called the control room to report what had happene This event caused the Division 2 Reactor Protection System to deenergize, resulting in a half scram and system isolations, including the Reactor Water Cleanup System, Division 2 Primary Containment Monitoring System, and the Primary Containment Leak l Detection System. All actuations were verified to have occurred as expected, except for the Division 2 Emergency Equipment Cooling Water actuation, which was determined to have been caused by a slightly slow relay actuation. The relay was subsequently replace The root cause of this event was an improper revision to the surveillance test procedur The revised step was unclear. The change was initiated by a new system engineer and was checked by two experienced engineers who assumed that the revision did not involve any technical changes. As a result, neither revieweridentified that the step allowed the procedure reader to select the wrong bus. The workers performing the test i also missed an opportunity to identify the problem.10 CFR 50, Appendix B, requires that activities affecting quality shall be prescribed by instructions of a type appropriate to the circumstances. Procedure 42.302.003 was considered to be a procedure that was not l appropriate to the circumstances in that the procedure allowed the reader to select an incorrect bus during a safety related system surveillance test. This was considered to be a violation of 10 CFR Part 50, Appendix B, Criterion V. (VIO 50-341/98003-04)
The licensee has had a history of problems with the group of surveillance test procedures intended to test the undervoltage circuits for safety-related buses related to inadequate procedure reviews, as documented in inspection Report No. 50-341/9601 The inspectors verified that the expected actuations occurred. The inspectors noted that the licensee's investigation of the event was prompt and thorough. This event was reported in accordance with 10 CFR 50.72, and will be the subject of LER 341/9800 Conclusions An inadvertent load shed on Safety Bus 72E was caused by an unclear procedure step, which was a violation. Inadequate reviews of the revised step and the lack of a questioning attitude by maintenance workers performing the test contributed to the even The licensee's investigation was prompt and thoroug M3.3 Relavs Not As-Found Tested Due to Confusina Werk Instructions ,
l Insoaction Scope (62707) ,
The inspectors reviewed the work packag3s associated with the control rod drive system work scheduled for the week of January 510 datermine the acceptability of scheduling and the potential for preconditioning. Findir.g3 were discussed with maintenance support (
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. Findinas and Observations On January 9, technicians replaced an Agastat relay that was part of the scram discharge volume high water level rod block circuitry for preventive maintenance purposes. The inspectors reviewed a series cf jobs on the same system to determine the combined effect of the entire work sequence. The work schedule included performing a surveillance test twice, once to obtain as-found data, and once as a post-maintenance test (PMT) following replacement of the relay. However, the inspectors identified that the surveillance test was only performed once, as a PMT. Maintenance personnel subsequently wrote CARD 98-10752 to evaluate this issue after the inspectors questioned the apparent omissio The Agastat relay was replaced during a scheduled preventive maintenance task. This task was scheduled with a quarterly surveillance functional test. The work was sequenced such that the surveillance was initially performed to collect as found dat Once as found data was collected, then the PM would be performed and the surveillance reperformed to obtain as left conditions. The inspectors reviewed the work instructions and determined that the maintenance workers had misinterpreted an instruction. The inspector reviewed the instruction and noted it stated to obtain as found data from the previously performed surveillance. However, the instruction referred to the surveillance used to collect the as found data. The work supervisor incorrectly concluded that as-found data could be copied from a previous test, performed 3 months earlier. The inspectors questioned whether this practice could be credited for satisfying the as-found testing requirements. The licensee reviewed the issue and determined that the as-found testing portion of this issue was not property conducted. The removed relay was subsequently bench-tested satisfactoril The inspectors reviewed other preventive maintenance work requests that replaced ,
Agastat relays, and did not identify any other work instructions that were similarly worde !
Work instructions in other work packages clearly required as-found functional testin The inspectors review of the entire work sequence did not identify any other work or testing issue Conclusion:
The inspectors identified that maintenance personnel incorrectly concluded that as-found relay timing data for an alarm circuit associated with the scram discharge instrument volume could be copied from a previously performed test.1he relay was replaced as part of regularly scheduled preventive maintenance. The old relay was successfully tested after the inspectors questioned the lack of as-found testing. The omission was caused by a cor* sing work package step. No additional examples were identifie M8 Miscellaneous Maintenance issues (92902)
M8.1 (Open) Unresolved item 50-341/ 97003-03: Review of the implications of the use of non-sequential procedure steps during post-maintenance testing. The inspectors were concemed that non-sequential steps from a surveillance test were used to demonstrate operability of motor-operated valves for the Reactor Core isolation Cooling (RCIC)
system. This resulted in a violation for an inadequate procedure. During review of this issue the inspector identified that Procedure MWC03, " Surveillance / Performance
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Package Control," continued to allow the use of non-sequential procedure steps to !
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perform partial surveillance tests. Partial surveillance tests are used to conduct post maintenance tests. The use of non-sequential steps in partial surveillance tests created the potential for creating procedure intent changes because the steps were lifted from approved procedures without an independent 50.59 review conducted for the partial surveillance test. Licensee corrective actions for this issue were reviewed (DER 97-1084) and were determined to address the procedure violation, but not this concem. The inspectors reviewed work packages for use of selected steps, and identified no additional examples, although the practice was still procedurally allowe Therefore, this item will remain open pending additional corrective actions by the license i l M8.2 (Closed) Violation 50-341/96006-03: Inadequate control of equipment during safety-l related battery charger maintenance. Test equipment was not seismically secured nor administratively approved for temporary storage in the area of safety-related equipment.
j The licensee determined that maintenance personnel were not familiar with the j operations and maintenance department requirements. Training was conducted for i electrical maintenance personnel on the requirements. A seismic analysis showed that the safety-related equipment would not have been adversely affected during a potential earthquake due to collisions with the loose test equipment. The inspectors noted that on ,
routine inspections that equipment staged for work was routinely seismically restrained. l This item is close M8.3 (Closed) Violation 50-341/96007-07: Reactor Core isolation Cooling (RCIC) System online maintenance resulted in unintentionally rendering the system inoperabl Operators failed to recognize that existing steam leakage past the steam admission valve would continue to fill the RCIC barometric condenser with a condensate pump tagged out of service. Due to work delays, a high level alarm was received for the RCIC barometric condenser. The system was declared inoperable when water level reached the top of the barometric condenser. The work was authorized without declaring the system l
inoperable because the operators failed to recognize the combined effect of existing i steam in leakage and the inability to remove water from the barometric condense Repairs were made to the steam admission valve to minimize steam leakag Precautions were added to both RCIC and the High Pressure Coolant injection (HPCI)
system operating procedures to indicate steps necessary to respond to a barometric i condenser high level alarm. The annunciator response procedures for the high level alarms were also similarly revised. Operator training was conducted specifically addressing this event. Corrective actions appeared adequate to prevent recurrence. This
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I lit. Enaineerina E2 Engineering Support of Facilities and Equipment l
E2.1 Low Pressure Turbine Overspeed Event Inspection Scope (92903)
The inspectors reviewed turbine performance data, UFSAR, Safety Evaluation Reports, I component drawings, technical manuals, control room logs, observed the conduct of post l maintenance testing and repairs to turbine components, interviewed turbine component l and system engineering personnel.
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During the switchyard failure and subsequent main generator load rejection event, the main turbine generator oversped to 124 percent of normal running spee Section 10.2.2.4 of the UFSAR stated that during the loss of electricalloads, the turbine generator emergency overspeed will not exceed 120 percent of rated speed. The l licensee conducted an investigation to determine the potential cause for the turbine
! overspeed conditio Turbine performance data indicated that the closure times for the No. 2 Low Pressure Stop Valve and No. 2 Low Pressure Intercept Valve were slower than those for the other i valves, allowing steam to be applied to the turbine for some additional time after the trip
! signal. In addition, the closure signal for the No. 2 Low Pressure Intercept Valve was never received on the sequence of events recorder. However, localindication showed that the valve was close During the investigation, valves were stroked multiple times. While closure times
- improved, the valves were observed to operate more slowly than expected. A historical l review of the turbine control and stop valves data revealed similar problems with the No. 4 Turbine Stop and No. 4 Intercept Valve in 1992 and 199 The licensee determined that the cause of the valve sticking was due to the corrosion of metal surfaces resulting in a rust buildup on intemal components. The licensee's l corrective action included the application of a graphite lubrication and exercising of the l valves, which restored the proper stroke times for the valves.
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The inspectors determined that the licensee's immediate corrective action was acceptable in the short term, but were concemed that, due to the high temperature and moist environment, the lubricant could degrade over time. The licensee was evaluating a graphite surface impregnation process as a long term solution. The inspectors
- determined that the licensee had reduced the frequency of exercising the turbine stop and control valves. The licensee concluded that the change in the periodicity of exercising the turbine valves could have contributed to the buildup of corrosion product In response, the licensee changed the valve stroking from every three months to two week (
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. Conclusions The inspectors concluded that slow turbine valve stroke times, which caused higher than design turbine speeds during a load rejection, were partially caused by reduced frequency of valve stroking. The inspectors were concemed with the corrective action to apply a graphite lubrication in a high temperature and moist environment, since the lubricant would lose its effectiveness over tim l E8 Miscellaneous Engineering issues (92902)
E Core Thermal Power Calculation Errors Inspection Scope The inspectors reviewed an issue involving core thermal power calculation errors
' documented in three licensee event reports (LERs) and assessed the adequacy of corrective actions (Unresolved item 50-341/96010-10). The issues discus.ad in the three LERs were also evaluated to determine the combined impact of the errors identifie Finally, the results of the licensee's review of the computation of reactor power, by both ,
computer and manual methods, were reviewed and discussed with the computer system f engineer and a reactor enginee Findinas and Observations
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The licensee identified three non-conservative errors in the reactor power calculation by heat balance in 1995-1997:
- An industry-identified issue that the 4 gpm reactor recirculation pump seal water flow was not accounted for, which was an 0.754 MWt error. (LER 341/95008)
e A computer scaling error used in calculating the power from reactor recirculation pumps resulted in an 2.919 MWt error. (LER 341/96013)
e The reactor water cleanup system flow input to the heat balance calculation was not properly density compensated by the calculation, resulting in an 0.6 MWt error. (LER 341/97008-01)
In response to the number of identified heat balance calculational errors, the licensee conducted a detailed review of the calculational method, code accuracy, and underlying assumptions used. This was performed with the assistance of the code vendor, General Electric. The licensee review determined that the heat balance calculations were accurate, and the methodology used was consistent with industry practices. All factors affecting reactor power were adequately accounted for in the calculation and each input parameter was obtained from calibrated instrumentation. No additional corrections were require The inspectors reviewed the licensee's corrective actions, and determined that the actions adequately addressed the deficiencies. The licensee concluded that the maximum licensed steady state thermal power level was exceeded slightly for very small amounts of time during Operating Cycles 1 through 3. No other operating cycles were
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adversely affected. Licensed full power limits are provided in the Technical Specifications. The safety significance of this issue was minimized because total error, when added to indicated power, amounted to less than 0.15 percent power. When maximum instrument inaccuracy (1.85 percent) is added, power would have been slightly
, less than the 102 percent used as the starting condition for analysis of all accidents and l transients. Exceeding the licensed thermal power limit is a violation of the Technical Specifications. However, this non-repetitive, licensee-identified and corrected violation is being treated as a Non-Cited Violation, consistent with Section Vll.B.1 of the NRC Enforcement Policy. The three LERs and the unresolved items are considered close (NCV 50-341/98003-05) Conclusions The licensee appropriately conducted a thorough review of all inputs to and calculations used to support the core thermal power computation. No additiorni errors were l
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identified. An NCV was identified for having exceeded the licennd core thermal power at one or more times in the past by a small fraction of a percen E8.2 {_ Closed) Unresolved item 50-341/96007-03: Emergency Operating Procedure entry due i to faulty Reactor Building sump levelindications. The licensee determined that the sump level probes were old and not well suited to the application. The capacitance-based probes indicated a higher-than-actual level when they became dirty. This condition led to control room operators noting on several occasions that the sump level recorders indicated level was greater that the level for entry into an Emergency Operating Procedure. The sump level recorders were subsequently determined to be erroneously l indicating high. Probe cleaning resulted in restoration of indication accuracy. The licensee replaced the probes with new ones of the same type as a short-term action in the Fall of 1997, and formed'a review team to identify a suitable replacement whose accuracy would not degrade significantly over time. The inspectors noted that no significant problems have been experienced since probe replacement. Based on the improved system performance and plans to replace the probes, corrective actions appear to adequately address the problem. This item is close E8.3 (Closed) LER 341/97004-00 and 01: Calibrations of a Primary Containment Oxygen l Monitor in deinerted environment challenging operability of a monitor in an inerted environment. This issue was addressed at a predecisional enforcement conference on l August 6,1997, and resulted in the NRC issuing a violation (50-341/97013-08). The licensee concluded that the experimentally determined maximum error did not result in l
exceeding the TS limit for maximum allowed oxygen concentration in primary i containment. The inspectors reviewed the licensee's data and reached the same
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conclusion. However, this event revealed that the licensee was slow in addressing l
anomalous indications. Corrective actions included reenforcement of expectations to
! promptly address anomalous indications. This item is close l
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I IV. Plant Support R8 Miscellaneous Radiation Protection and Chemistry lasues R8.1 [ Closed) Unresolved item 50-341/97003-14: Review of licensee actions to ensure timely access to radiologically restricted areas during off-normal hours. In response to the NRC's concem, the licensee added provisions to administrative procedure MRP08,
" Radiologically Restricted Area Access Denial / Reinstatement," to grant immediate access to Radiologically Restricted Areas for NRC and other essential personnel by providing for the use of qualified escorts. The inspectors determined that these changes were adequate to ensure unfettered access as required by 10 CFR 50.70. This item is close P8 Miscellaneous Emergency Preparedness issues '
P8.1 (Closed) inspection Followup Item 50-341/%006-11: Emergency Operations Facility status boards were inadequate for trending of plant parameters or recording Technical Support Center priorities and offsite protective measures. The inspectors observed the operations in the Emergency Operations Facility during the emergency drill conducted on March 4. Status boards had been changed to include the missing data, and the status boards were effectively used to record and trend the infonnation. This item is close V. Manaaement Meetinas X1 Exit Meeting Summary The inspectors presented the inspection results to members of licensee management at the conclusion of the inspection on March 16,1998. The licensee acknowledged the findings presented. The inspectors asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identifie .
PARTIAL LIST OF PERSONS CONTACTED Licensee S. Booker, Electrical Maintenance Superintendent D. Cobb, Operations Superintendent W. Colonnello, Work Week Manager R. Delong, Superintendent, System Engineering l
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T. Dong, NSSS, Technical Engineering P. Fessler, Plant Manager J. Greene, Superintendent of Maintenance Support K. Howard, Superintendent, Plant Support Engineering E. Kokosky, Superintendent, RP and Chemistry J. Korte, Director, Nuclear Security R. Laubenstein, Mechanical Maintenance Superintendent P. Lynch, NSS, Operations R. Matthews, l&C Maintenance Superintendent W. Miller, Work Week Manager J. Moyers, NQA Director
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N. Peterson, Acting Director, Nuclear Licensing
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J. Plona, Technical Director T. Schehr, Operating Engineer J. Sweeney, Supervisor of Audits, NQA l
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l INSPECTION PROCEDURES USED
IP 37551: Onsite Engineering IP 62707: Maintenance Observation IP 71707: Plant Operations
, IP 92700: Onsite Followup of Written Reports of Nonroutine Events at Power l
Reactor Facbties
! IP 92902: Followup - Engineering l IP 92903: Followup - Maintenance IP 93702: Prompt Onsite Response to Events at Operating Power Reactors ITEMS OPENED, CLOSED, AND DISCUSSED Opened 50-341/98003-01 DEV Insufficient Number of Self-Contained Breathing Apparatus in Control Room
, 50-341/98003-02 IFl CCHVAC Design Deficiency and Lack of Portable Chlorine l Detection Equipment l
50-341/98003-03 IFl No Stipulation on Watch Scheduling for Two Operators With Respirator Restrictions 50-341/98003-04 VIO Procedure 42.302.003 Inadequate l 50-341/98003-05 NCV Maximum Licensed Power Level Exceeded l
Closed 50-341/95008-00 LER Reactor Recirc Pump Seal Water Flow Not Accounted For 50-341/96005-02 IFl Root Cause Evaluation Results for Failure of RCIC Minimum Flow Valve l 50-341/96006-03 VIO Inadequate Control of Equipment During Safety Related Battery
! Charger Maintenance l 50-341/96006-11 IFl Emergency Operations Facility Status Boards inadequate for j l Trending Plant Parameters l l 50-341/96007-03 URI Emergency Operating Procedure Entry Due to Faulty Reactor Building Sump Level Indication /96007-07 VIO RCIC System Online Maintenance Resulted in Unintentionally Rendering System inoperable l 50-341/96010-20 URI Core Thermal Power Calculation Errors ~
l 50-341/96013-00 LER Computer Scaling Error Used in Calculating Power From Reactor Recirc Pumps Resulting in Error 50-341/97002-02 VIO Lack of Required Procedures for Operation of Offsite Power System j 50-341/97003-14 URI Review of Licensee Actions to Ensure Timely Access to i Radiologically Restricted Areas During Off-Normal Hours !
50-341/97004-00 LER Calibrations of Primary Containment Oxygen Monitorin De-Inerted Environment 50-341/97004-01 LER Calibrations of Primary Containment Oxygen Monitorin De-Inerted Environment 50-341/97007-00 LER Failure of Reactor Building Ventilation During Shutdown Conditions
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50-341/97008-01 LER Reactor Water Cleanup Flow Input to Heat Balance Calculation Not Properly Density Compensated by Calculation 50-341/97013-07 IFl Lack of Training and Procedural Direction for Use of Air Masks in Control Room 50-341/98003-05 NCV Maximum Licensed Power Level Exceeded Discussed 50-341/97003-03 URI Review of Use of Non-sequential Procedure Steps During PMT l
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LIST OF ACRONYMS USED CARD Condition Assessment Resolution Document CCHVAC Control Center Heating Ventilation Air Conditioning )
EDG - Emergency Diesel Generator j ECCS Emergency Core Cooling System i EPPM Equipment Performance and Predictive Maintereance HPCI High Pressure Coolant injection LCO Limiting Condition for Operation .
LPCI Low Pressure Coolant injection MOP Motor Operated Potentiometer J NASS Nuclear Assistant Shift Supervisor NCV Non-Cited Violation NRC Nuclear Regulatory Commission NSS Nuclear Shift Supervisor PMT Post Maintenance Testing RCIC Reactor Coolant Isolation System RG Regulatory Guide RHR- Residual Heat Removal TS Technical Specification UFSAR Updated Final Safety Analysis Report
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