IR 05000271/1998010
| ML20237C092 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 08/14/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20237C090 | List: |
| References | |
| 50-271-98-10, NUDOCS 9808200194 | |
| Download: ML20237C092 (18) | |
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U.S. NUCLEAR REGULATORY COMMISSION
REGION I
Docket No.
50-271 Licensee No.
DPR-28 Report No.
98-10 Licensee:
Vermont Yankee Nuclear Power Corporation Facility:
Vermont Yankee Nuclear Power Station Location:
Vernon, Vermont Dates:
June 14 - July 18,1998 Inspectors:
Brian J. McDermott, Senior Resident inspector Edward C. Knutson, Resident inspector Suresh K. Chaudhary, Senior Reactor Engineer Approved by:
Curtis J. Cowgill, Ill, Chief, Projects Branch 5 Division of Reactor Projects i
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EXECUTIVE SUMMARY Vermont Yankee Nuclear Power Station NRC Inspection Report 50-271/98-10 This iritegrated inspection included aspects of licensee operations, engineering, maintenance, and plent support. The report covers a five-week period of resident inspection; in addition, it includes the results of an announced inspection by a regional inservice inspection program specialist.
Operations Operators identified an inconsistency in the Technical Specification (TS) requirements for automatic deactivation of the turbine stop and control valve fast closure scram signals.
Immediate corrective actions to reduce power and activate the scram inputs according to the most limiting TS were appropriate. (Section 01.1)
VY identified two drain valves in the torus vent system were not in their required position during the June 1998 reactor startup. Immediate corrective actions were appropriate and provided assurance that no other valve position discrepancies existed. The fact that the valves were open when primary containment was required is a violation, however this event did not have a significant impact on plant safety. This licensee identified and corrected violation is being treated as a Non-cited Violation. (Section 01.2)
A required 1-hour notification to the NRC for the open torus vent system drain valves was delayed by 30 days. The failure to make the report as required by 10 CFR 50.72 is considered a Non-cited Violation. (Section 01.2)
A review of 1997 and 1998 LERs found that VY has been slow in completing some root cause evaluations and corrective actions. A large number of these LERs related to old design issues which VY is actively identifying and, overall, the completed corrective actions have been good. No impact on plant safety has been observed as the result of the delays. VY management has acknowledged this trend and is assessing the need for process improvements. (Section 08.1)
Maintenance A number of material condition deficiencies exist in the service water pump room and this area is a notable exception to the overall good material condition of the plant. The i
deficiencies are actively tracked and evaluated by System Engineering as part of the Service Water System Health Report. VY has planned corrective actions and the inspector l
identified no operability concerns. (Section M2.1)
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l The licensee appropriately identified an adverse trend in SW system reliability and established the performance monitoring required by 10 CFR 50.65, Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants' Although long term
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corrective actions have not yet been implemented, monthly evaluations are in progress and the established monitoring goals should ensure implementation of these improvements remains a priority.
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The VY staff took appropriate corrective actions in response to a failure of the "B" core spray pump supply breaker on March 18,1998. The subsequent root cause investigation
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was thorough and the associated long term corrective actions were appropriate. VY's reporting of this event was consistent with the requirements of 10 CFR 50.72 and 10 CFR 50.73. The f ailure to provide adequate procedures for maintenance of 4160 volt safety-related circuit breakers was characterized as a Non-cited Violation.
Enaineerina The Inservice inspection (ISI) program was properly controlled and had been satisfactorily implemented. it included acceptable ASME program coverage, qualified personnel, I
approved procedures, proper implementation, appropriate examination documentation, and VY oversight. The ISI personnel were knowledgeable of ISI and ASME Code requirements.
The documentation supporting the program and ISI examinations was appropriate and readily available. Observations and indications had been clearly documented and resolved
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satisf actorily. (Section E3.1)
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TABLE OF CONTENTS l
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i EX ECUTIVE Sf lMM ARY.............................................. ii j
TA BLE O F CO NT ENTS.............................................. iv Summary of Plant Status
............................................1 1. Operations
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Conduct of Operations.................................... 1 01.1 Main Turbine Stop/ Control Valve Fast Closure Scram Bypass.... 1 01.2 Torus Vent System Drain Valves Found Open When Required to be Closed..........................................3
Miscellaneous Operations issues............................. 4 08.1 Review of Notification Evaluation Process.................. 4 ll. M a inte n a nce................................................... 5 M1 Conduct of Maintenance................................... 5 M 1.1 Maintenance Observations............................ 5 M1.2 Surveillance Observations............................. 6 M2 Maintenance and Material Condition of Facilities and Equipment....... 7 M2.1 Service Water (SW) System Performance Review............ 7 M2.2 Feedwater Regulating Valve Loose Parts.................. 8 M8 Miscellaneous Maintenance issues............................ 9 MS.1 (Closed) Licensee Event Report (LER) 50-271/98-006-00....... 9 I l l. E ngi n e e rin g.................................................. 10 E3 Engineering Procedures and Documentation.................... 10 E3.1 Inservice inspection.........
......................10 IV. Plant Support
................................................12 R1 Radiological Protection and Chemistry (RP&C) Controls............ 12 R1.1 Contaminated Area Entry Requirements.................. 12
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R1.2 Radiation Work Permit (RWP) for Torus Work..............
l F2 Status of Fire Protection Facilities and Equipment................13 F2.1 Diesel Driven Fire Pump Material Problem................. 13 V. Management Meetings.......................................... 13 X1 Exit Meeting Sum m ary................................... 13 e
X2 Review of Updated Final Safety Analysis Report (UFSAR)........... 13 LIST OF AC RO NYM S USED.......................................... 14
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Report Details Summarv of Plant Status At the beginning of the inspection period, Vermont Yankee (VY) was returning to power operation following the reactor scram of June 9. The scram event is discussed in detail in NRC Inspection Report 50-271/98-09, dated July 10,1998. The main generator was synchronized to the grid at 5:03 a.m. on June 14, and full power operation was achieved on June 16. With the exception of power reductions to perform planned surveillance testing and rod pattern adjustments, VY operated at 100 percent power for the remainder of the inspection period.
l. Operations
Conduct of Operations'
01.1 Main Tuibine Stoo/ Control Valve Fast Closure Scram Bvoass a.
Insoection Scope (71707)
The inspector reviewed a licensee-identified inconsistency in Technical l
Specifications (TS) regarding the reactor power level at which the main turbine stop and control valves (TSV/TCV) fast closure input to the reactor protection system (RPS) can be bypassed, b.
Observations and Findinas During the return to full power operations on June 14, control room operators noted I
that ?he TSV/TCV fast closure bypass did not automatically clear, as expected, when core thermal power exceeded 30 percent. At the time of discovery, reactor power was approximately 32 percent. Operators promptly reduced power to less than 30 percent and Event Report (ER) 98-1423 was initiated.
TS 2.1.F states that, " Turbine control valve fast closure scram shall, when operating at greater than 30 percent of full power, trip upon actuation of the turbine control valve fast closure relay." This requirement does not have an associated allowed outage time. TS Table 3.1.1 presents required trip settings for the various inputs to the RPS. For the TSV/TCV fast closure, the table indicates, "A turbine stop valve closure and generator load rejection bypass is permitted when the first I
stage turbine pressure is less than 30 percent of normal (220 psia)." A footnote for Table 3.1.1 provides an 8-hour allowed outage time for this function.
l The TSV/TCV fast closure scram bypass logic utilizes main turbine first stage pressure as the sensed parameter to determine plant power level. First stage pressure is directly proportional to reactor power for a given steam plant alignment.
However, changes in the steam plant alignment that affect the amount of feedwater l
' Topical headings such as 01, M8, etc., are used in accordance with the NRC standardized l
reactor inspection report outline. Individual reports are not expected to address all outline topics.
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heating (such as use of the turbine bypass valves and operation of the feedwater heaters) disrupt the proportionality because the feedwater heating affects reactor power. In order for a fixed value of first stage pressure to be used as an indication that reactor power is less than 30 percent, it must account for the worst case j
steam plant alignment that could exist at 30 percent power. This issue was l
identified by General Electric in a service information letter (SIL 423), dated May 31, 1985.
VY's review determined that with the pressure setpoint listed in TS Table 3.1.1, the TSV/TCV fast closure scram would have cleared at approximately 34% reactor power. When operators discovered this issue, the first stage pressure was below the specified in TS Table 3.1.1 and the bypass had not cleared.
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in response to ER 98-1423,VY disabled the automatic bypass feature of the f
TSV/TCV fast closure scram to satisfy the requirements of both TS 2.1.F and TS Table 3.1.1. The circuit was deenergized and tagged to prevent inadvertent operation while final corrective actions are being developed.
The inspector reviewed the FSAR description of the TCV fast closure scram. The
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purpose of the scram is to provide a satisfactory margin to core thermal-hydraulic l
limits in response to a turbine trip at power. In describing the 30 percent power i
automatic bypass, the FSAR states that TSV/TCV closure from such a low initial power level does not constitute a threat to the integrity of any barrier to the release l
of radioactive material. Therefore, leaving the scram in effect at less than 30 l
percent is a conservative action. The inspector also determined that manually
removing the TSV/TCV fast closure scram bypass as a short term corrective action was consistent with the requirements of TS 2.1.F, TS table 3.1.1 and the VY
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design basis.
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VY submitted Licensee Event Report (LER)98-022," Control valve fast closure and turbine stop valve closure scram bypass did not reset when greater than 30 percent j
core thermal power," on July 14. At the time of submittal, the cause of the event i
was still being evaluated, and VY planned to supplement the LER. The inspector i
reviewed the LER and determined that it adequately described the event as required by 50.73. Therefore, LER 98-022, Rev. O, is closed.
From a review of computer records, the inspector determined that core thermal
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power was greater than 30 percent for approximately 38 minutes and reached a maximum power of 31.4 percent. This licensee identified violation of TS 2.1.F did not have any impact on plant safety and was the result of an inconsistency in the TS. Appropriate corrective actions for this discrepancy have been initiated. This failure constitutes a violation of minor significance and is not subject to formal enforcement action.
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Conclusions Operators identified an inconsistency in the Technical Specification (TS)
requirements for automatic deactivation of the turbine stop and control valve fast t
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closure scram signals. Immediate corrective actions to reduce power and activate the scram inputs according to the most limiting TS were appropriate. A short period of operation with the less limiting TS setting in effect did not impact plant safety.
This issue was dispositioned as a rrinor violation and was not subject to formal enforcement action.
01.2 Torus Vent System Drain Valves Found Ooen When Reouired to be Closed a.
Insoection Scoce (71707)
l The inspector reviewed the events surrounding VY's identification of two drain valves in the torus vent system that were found to be out of their required position.
b.
Observations and Findinas i
While performing a routine surveillance to verify the position of safety system locked valves, VY identified a minor discrepancy concerning a residual heat removal (RHR) system valve. In response to this finding, VY initiated an expanded valve position verification. On June 14, with the reactor at approximately 4 percent
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power, two valves in the torus vent system (TVS) listed as closed in the I
containment isolation valve lineup sheet, were found to be open. The valves, TVS-I 86A and TVS-868, are located in series on a 0.75 inch drain line between the torus rupture diaphragm and the normally closed downstream motor-operated isolation valve, TVS-86. Because of their location, the open valves did not provide an open pathway from the primary containment into secondary containment. The valves were promptly returned to their required positions and additional valve position verifications were performed.
VY initiated an investigation to determine the cause of the TVS valves being out of their required positions. In reviewing the event, VY determined the open valves constituted a condition outside the plant's design basis. Specifically,in the event of a design basis loss of coolant accident (LOCA), the VY emergency operating procedures would lead to containment flooding. Post accident containment pressurization, along with the head of water required to achieve core coverage, could cause the TVS diaphragm to rupture. The two open drain valves downstream of this diaphragm would then allow water to leak out of the primary containment.
Although this leakage would be contrary to the FSAR functional requirements for primary containment, the liquid leakage would be contained within the secondary containment.
LER 98-020,"Out of position isolation valves allow degradation of primary containment integrity, cause for valves out of position is under investigation," was submitted on July 14. VY will be submitting a supplemental LER to report the cause and long term corrective actions for this event. Based on review of the initial i
LER, the inspector determined that it adequately described the event and therefore the initial report, LER 98-020, Rev. O, is closed.
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TS 3.7.A.2, Station Containment Systems, requires, in part, that primary containment integrity be maintained at all times when the reactor is critical. VY procedure OP 0105, Reactor Operations, Phase 1, step A.1 requires a prerequisite
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Implementing procedures for establishing primary containment clearly identified the subject TVS drain line valves were required to be closed. Contrary to these requirements, the valves were discovered to be open on June 14 with the reactor critical. The inspector determined this noncompliance did not have an adverse consequence on plant safety. The 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. (NCV 98-10-01)
During processing of LER 98-020 on July 14, VY identified that the event should have been reported in accordance with 10 CFR 50.72, as a condition outside the plant's design basis and made a one-hour non-emergency ENS notification. VY's thirty day delay in making a required one-hour notification is a violation of 10 CFR 50.72. The inspector determined that long term corrective actions for a similar violation issued on July 1,1998, (VIO 50-271/98-08-03)have not yet been implemented. Based on the timing of the two violations, and the nature of the corrective actions, the thirty day delay in making a report on the two valves is not considered a repetitive violation. As such, 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. (NCV 98-10-02)
c.
Conclusions VY identified two drain valves in the torus vent system were not in their required position during the June 1998 reactor startup. Immediate corrective actions were appropriate and provided assurance that no other valve position discrepancies existed. The fact that the valves were open when primary containment was required is a violation, however this event did not have a significant impact on plant safety. This licensee identified and corrected violation is being treated as a Non-cited Violation.
A required 1-hour notification to the NRC for the open torus vent system drain valves was delayed by 30 days. The failure to make the report as required by 10 CFR 50.72 is considered a Non-cited Violation, in part, because corrective actions for a similar violation are in the process of being implemented.
Miscellaneous Operations issues 08.1 Review of Notification Evaluation Process a.
Inspection Scone (92700,90712)
Event notifications and event reports, pursuant to 10 CFR 50.72 and 50.73, respectively, for the period of January 1997 through July 1998 were reviewed to
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assess the effectiveness of VY's process for evaluating potentially reportable events.
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Observations and Findinas
.VY submitted forty-four Licensee Event Reports (LERs) between January 1997 and July 1998. A large number of the LERs were generated as the result of the licensee's initiative on design basis documentation. However, twenty-six of the forty-four LERs required supplemental reports because the licensee was unable to determine the cause of the event within the 30-day reporting period required by 10 CFR 50.73.
The inspector reviewed VY's database which tracks LER commitments and found that over half of the LERs during the period of interest had commitment due dates which were not met.
Since April 1998, the NRC has cited four violations against VY for the failure to meet reporting requirements of 10 CFR 50.72 or 50.73. Based on discussions with VY plant management, the licensee intends to address corrective actions to improve the deportability evaluation process in the response to the most recent of these violations, VIO 98-08-03.
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Conclusions A review of 1997 and 1998 LERs found that VY has been slow in completing some root cause evaluations and corrective actions. A large number of these LERs related to old design issues which VY is actively identifying and, overall, the completed corrective actions have been good. No impact on plant safety has been observed as the result of the delays. VY management has acknowledged this trend and is assessing the need for process improvements.
11. Maintenance M1 Conduct of Maintenance M1.1 Maintenance Observations a.
insoection Scone (62707)
The inspector observed portions of a plant maintenance activity to verify that the j
correct parts and tools were utilized, the applicable industry code and technical i
specification requirements were satisfied, adequate measures were in place to ensure personnel safety and prevent damage to plant structures, systems, and h
components, and to ensure that equipment operability was verified upon completion of post maintenance testing.
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b.
Observations, Findinas, and Conclusions
The inspector observed portions of planned maintenance on the "B" reactor feedwater pump on July 14 and 15. This maintenance included disassembly of the feedwater pump and was of interest because the June 9 reactor scram resulted from foreign materialin the feedwater system.
The inspector observed maintenance on the lower pump casing flange and boroscopic inspection of the discharge check valve weld to the pump discharge.
Openings to both areas were posted as level ill cleanliness areas, and a dedicated individual was recording items as they entered and exited the areas, as required by VY instruction AP-6024, " Plant Housekeeping and Foreign Material Exclusion / Cleanliness Control." However, the inspector noted that VY supervisory personnelidentified some personalitems belonging to the work crew were not adequately secured. The VY supervisor took immediate action to correct the situation and, the following day, the inspector observed good FME practices during installation of the rotating assembly.
M1.2 Surveillance Observations a.
Insoection Scope (61726)
The inspector observed portions of a surveillance test to verify proper calibration of test instrumentation, use of approved procedures, performance of work by qualified personnel, conformance to Limiting Conditions for Operations (LCOs), and correct post-test system restoration, b.
Observations, Findinas, and Conclusions The inspector observed portions of the core spray pump quarterly surveillance test performed on July 8.
The inspector noted a minor problem with FME control prior to installation of test gauges in preparation for the surveillance. Specifically, two gauges and their connecting hoses were staged for the activity without FME plugs installed. The equipment was on a cart and there was no immediate risk of foreign material introduction. The inspector informed the shift supervisor of the observation, and later discussed it with plant management. VY management stated their expectation was that unattended test equipment would be covered to prevent foreign material intrusion and this expectation was emphasized with the work crew.
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M2 Maintenance and Material Condition of Facilities and Equipment M2.1 Service Water (SW) System Performance Review a.
Insoection Scope (62707)
The inspector performed a partial walkdown of the service water system, with emphasis on observing the material condition of the system. Equipment in the intake structure service water pump room was observed to have extensive corrosion on exposed metal parts, and active pump packing leaks which resulted in standing puddles of water. Based on these observations, the inspector reviewed SW System Health Report for the quarter ending June 30,1998, to assess VY's tracking and corrective action plans for material condition issues. In addition, the inspector examined VY's implementation of 10 CFR 50.65 requirements and the information available for system performance monitoring.
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Observations and Findinos The safety-related SW system is normally operating and consists of two cross-connected subsystems supported by a total of four pumps. VY's maintenance rule performance monitoring program tracks SW based on the system, subsystem train, and pump train levels.
In October 1997, the licensee's SW performance evaluation concluded the system was not demonstrating acceptable performance. VY designated SW as a " Category (a)1" system under their maintenance rule program and developed a performance improvernent plan with goals and goal monitoring. The majority of SW system problems resulted from silt and sand deposition in the piping or from corrosion. A SW performance improvement plan was approved by the plant manager on October 13,1997.
As of June 1998, there were five SW system maintenance rule functional failures (MRFFs) in the rolling three year period. VY has implemented corrective actions for individual SW deficiencies, however, system improvements identified during the 1997 evaluation have not yet been implemented. In the interim, the system is subject to a monthly performance trend review and a review of all new events to determine if additional short term actions are required. A major planned improvement to prevent some of the recurring deficiencies is the installation of a penetrating biodispersant system.
The inspector noted that the performance goal established by VY is based on SW system performance after installation of this modification. Therefore, the SW system will remain a " Category (a)1" system until the modification is complete or the performance improvement plan is revised. The inspector concluded the maintenance rule status of SW will ensure close monitoring by plant staff and management until corrective actions are implemented which improve the overall system performanc _ _ - - _ - _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ - _ _ _ _
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The inspector observed that the VY's SW System Health Report provides a comprehensive summary of the overall system condition. Thirteen performance
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categories we tracked in order to assess the overall condition and include issues such as material condition, test deficiencies, trending, and work order backlog.
Material condition deficiencies observed by the inspector, such as leaking pump seals, were identified in the Health Report and were addressed as repeat occurrences where appropriate.
As of June 30,1998, there were 69 open commitments in the licensee's database related to the SW system. The majority of these commitments relate to design issues, but some relate to long term improvements in the SW system's material condition. A sample of four ERs generated in the last year was reviewed. The inspector found that each ER had an appropriate operability determination and that corrective actions were complete or in progress. No concerns were identified.
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Conclusions A number of material condition deficiencies exist in the service water pump room and this area is a notable exception to the overall good material condition of the plant. The deficiencies are actively tracked and evaluated by System Engineering as part of the Service Water System Health Report. VY has planned corrective actions and the inspector identified no operability concerns.
The licensee appropriately identified an adverse trend in SW system reliability and established the performance monitoring required by 10 CFR 50.65, Requirements
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for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants. Although
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long term corrective actions have not yet been implemented, monthly evaluations are in progress and the established monitoring goals should ensure implementation of these improvements remains a priority.
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M2.2 Feedwater Reaulatino Valve Loose Paris During a routine plant tour, the inspector noted the "B" main feedwater regulating valve position indicator was loose on its shaft, due to a loose set screw.
From discussions with the licensee, the inspector determined that the position indicator provides a main control board indication and does not affect any automatic control systems. A work order was generated and the problem was corrected the following day.
Although this problem had no operational impact, the inspector was concerned that a loose part had developed on a feedwater regulating valve and had r.ot been identified by the licensee. The feedwater regulating valves are in a high vibration l
environment, and the mechanical connections appear to be susceptible to vibration-l induced loosening. The inspector discussed this with VY management, who acknowledged the concern.
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M8 Miscellaneous Maintenance issues M8.1 (Closed) Licensee Event Reoort (LER) 50-271/98-006-00: Inadequate maintenance j
procedure for safety class breakers established conditions which could have led to j
the failure of multiple safety class breakers a.
Inspection Scope (93702,92700,90712)
j LER 98-006-00idenoried that inadequate maintenance procedures led to the March 18,1998, failure of the "B" core spray pump safety class supply breaker.
This maintenance problem could have adversely impacted similar 4160 volt General Electric (GE) Magne-blast circuit breakers (Model AM4.16-250-8HB). The inspector reviewed VY's immediate response to this event, the root cause assessment, and
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the corrective actions, to verify compliance with NRC rules and regulations.
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Observations and Findinas On March 18,1998, the inspector reviewed the licensee's immediate actions in I
response to the discovery of the "B" core spray pump failure and determined those actions were adequate. Upon discovery, the control room operators properly declared the "B" train of core spray inoperable and entered the TS limiting condition for operation. The maintenance staff racked-out the failed breaker and replaced it with a t, pare 4160 volt breaker. The spare breaker operability verification was performed and the core spray system LCO was exited. The shift supervisor directed actions to confirm all installed 4160 volt GE Magne-blast breaker closing springs were properly charged.
Subsequent troubleshooting of the as-found "B" core spray pump breaker in the maintenance shop identified the potential common cause failure mechanism of mechanical binding. VY determined the failure was due to mechanical binding of the closing spring latching pawl that resulted from the combined effects of dried lubricant, an improperly installed bushing, and an extra retaining washer.
Upon discovery of this potential common cause failure mechanism, the VY staff re-l examined the deportability of the March 18,1998 single component failure and
concluded it was reportable per 10CFR50.72(b)(2)(iii)and 50.73(a)(2)(v). The inspector determined that VY's reporting of this event was consistent with NUREG-1022, " Event Reporting Guidelines 10CFR 50.72 and 50.73," Revision 1, dated l
January 1998. The inspectors review of LER 98-006-00found that VY had I
adequately described the event, properly assessed the root cause, and developed l
reasonable corrective actions. The inspector identified no reporting violations as a
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result of this event.
l TS 6.5, Plant Operating Procedures, requires detailed written procedures be prepared and used for preventive and corrective maintenance which could have an effect on the safety of the reactor. VY failed to provide adequate procedures for maintenance of the 4160 volt breakers and, as a result, the "B" core spray pump
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breaker failed to return to its normal standby condition following a routine I
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surveillance. This non-repetitive, licensee-identified and corrected violation is being treated as a non-cited violation, consistent with Section Vil.B.1 of the NRC Enforcement Policy. (NCV 98-10-03)
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Conclusions The VY staff took appropriate corrective actions in response to a failure of the "B"
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core spray pump supply breaker on March 18,1998. The subsequent root cause investigation was thorough and the associated long term cotrective actions were appropriate. VY's reporting of this event was consistent with the requirements of 10 CFR 50.72 and 10 CFR 50.73. The failure to provide adequate procedures for maintenance of 4160 volt safety-related circuit breakers was characterized as a Non-cited Violation.
Ill. Engineering E3 Engineering Procedures and Documentation E3.1 Inservice inspection a.
Insoection Scope (73753)
This inspection was performed to confirm that the inservice inspection (ISI), repair, and replacement of Class 1,2, and 3 pressure retaining components has been performed in accordrace with the Technical Specification (TS), applicable ASME Code and NRC requirements, and industry initiatives, including any relief requests granted by the NRC.
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The scope of the inspection included the review of the ISI program plan for Vermont Yankee Nuclear Generating Station (VY), procedures, qualification of inspection /
examination personnel, results of the ISI activities in the 20th refueling outage (1998), and schedule of planned ISI for the 1999 refueling outage, b.
Observations and Findinos
- Procedures and Personnel The inspector determined that VY had conducted the required exams and completed a comprehensive report of their findings. The inspector reviewed the report and observed that concerns identified by these inspections have been addressed by
analysis, repair, or replacement. On May 4,1998, VY transmitted the results (BVY 98-67) of these inspections / examinations to the NRC for review.
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The inspector reviewed the nondestructive examination procedures used by VY and found the procedures clearly written, with adequate explanation of the technical basis and work control. Additionally, the inspector reviewed approximately fifteen data reports (covering visual test (VT), liquid penetrant test (PT), magnetic particle test (MT), or ultrasonic test (UT)), and determined that examination results, l
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evaluation results, and corrective action, if any, were properly recorded as specified in the ISI program. The documentation of the examination and evaluations were satisfactory.
The inspector reviewed the qualification / certification of the contractor personnel engaged in the non-destructive examination (NDE) of the ISl program and determined that NDE inspectors were properly qualified by formal and practical training, and were certified to proper levels of inspection / examination responsibility in the different examination methods. The qualification and certification of NDE inspectors was in accordance with the requirements of SNT-TC-1 A, as mandated by ANSI /ASME N45.2.6-1978,which is accepted by Code case N-424.
- Review of NDE Data Reoorts The inspector reviewed the above data sheets for surface and volumetric examinations, and associated deviation /nonconformance reports, and determined that: 1) the examinations were performed by appropriately certified inspectors, and reviewed and approved by properly qualified / certified technical reviewers; and 2)
the unacceptable indications disclosed by these examinations were adequately evaluated and acceptably resolved. Radiographic examinations and accompanying data reports and evaluations were not reviewed.
The inspector verified the Authorized Nuclear Inservice inspector (ANil) oversight of the ASME Section XI NDE ISI activities. The ASME Code,Section XI, IWA-2000, requires a power reactor licensee to provide opportunity to the ANil to review NDE procedures, personnel certification, and data reports. The ANil review of the data reports was apparent.
- OA Audits and Self-Assessments In the past 24 month period, the VY QA organization has performed an audit /self-assessment in the ISI area. The audit covered significant items and identified some minor deficiencies that were reported to the ISI program management for resolution, who had taken steps to resolve these deficiencies.
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Conclusions The ISI program was properly controlled and had been satisfactorily implemented. It included acceptable ASME program coverage, qualified personnel, approved procedures, proper implementation, appropriate examination documentation, and Vermont Yankee oversight. The ISI personnel were knowledgeable of ISI and ASME Code requirements. The documentation supporting the program and ISI examinations were appropriate and readily available. Observations and indications had been clearly documented and resolved satisfactorily.
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IV. Plant Support R1 Radiological Protection and Chemistry (RP&C) Controls R1.1 Contaminated Area Entry Requirements During the CS pump surveillance conducted on July 8, the inspector noted that RP coverage was not provided during the test. The technicians performing the surveillance needed to obtain vibration readings from a point inside a posted contaminated area. They interpreted the posting to indicate that the area they needed acceso to was clean, and reached across the area boundary to obtain the readings. Although their interpretation was correct, the inspector considered that such practice cc.uld lead to complacency in taking radiological precautions. The inspector discust ed these observations with VY managernent, who acknowledged the concern. Pri(r to the close of the inspection period, VY initiated action to change the barrier of concern, so that it more closely bounded the contaminated area. The inspector had no further questions in this area.
R1.2 Radiation Work Permit (RWP) for Torus Work The inspector reviewed RWP 98-106, dated March 21,1998, which was used to control all work inside the torus associated with the refueling outage 20 torus project. This RWP established the requirements for work by both VY and contractor personnel. Based on the changing nature of the work environment, the protective clothing requirements and other specialinstructions were deferred to job specific briefings held just prior to entry into the torus. Twenty four hour coverage was provided by radiation protection (RP) technicians at the torus entry check point.
Additional information regarding the licensee's radiation protection program performance during this activity is discussed in NRC Inspection Report 50-271/98-08, Section R1.1.
The inspector found that general area surveys were performed for this RWP and that remote radiation monitoring devices were used to allow real-time assessment of j
changing radiological conditions caused by the use of certain equipment. RP J
technicians periodically logged the dose rates for this equipment which included the pre-filter (roughing) located on the platform inside the torus and the vacuums used to remove debris from the pre-filters. Dose limits for change out of the filters and vacuums were pre-established and closely monitored.
Based on a review of plant records, the intpector concluded that VY provided appropriate radiation work permit controls and instructions for work in the torus during the refueling outage. The use of remote radiation monitoring for certain l
activities allowed RP technicians to make real-tirne assessments of changing i
radiological conditions and helped to ensure radiation worker dose was maintained l
as low as reasonably achievable.
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F2 Status of Fire Protection Facilities and Equipment F2.1 Diesel Driven Fire Pumo Material Problem During a planned maintenance outage of the diesel driven fire pump, the inspector noted that the diesel exhaust pipe was deteriorating due to rust. Specifically, the horizontal run of piping leading up to the discharge flapper was rusted through in some areas along the top of the pipe. The inspector was concerned that this condition would allow rain water to collect in the exhaust system and possibly affect operation of the diesel. VY responded by replacing the deteriorated portion of the exhaust pipe prior to returning the diesel driven fire pump to service. VY concluded that the pump had been operable prior to the condition being identified, based on consistent satisfactory completion of monthly surveillance. The inspector had no further concerns on this matter.
V. Management Meetings X1 Exit Meeting Summary The resident inspectors met with licensee representatives periodically throughout the inspection and following the conclusion of the inspection on August 10,1998.
At that time, the purpose and scope of the inspection were reviewed, and the preliminary findings were presented. The licensee acknowledged the preliminary inspection findings.
The inspector asked the licensee whether any material examined during the inspection should be considered proprietary. No proprietary information was identified.
X2 Review of Updated Final Safety Analysis Report (UFSAR)
A recent discovery of a licensee operating their facility in a manner contrary to the Updated Final Safety Analysis Report (UFSAR) description highlighted the need for a special focused review that compares plant practices, procedures and/or parameters to the UFSAR description. While performing the inspections discussed in this report, the inspectors reviewed the applicable portions of the UFSAR that related to the area inspected. The inspectors verified that the UFSAR wording was consistent with the observed practices and procedures and/or parameters.
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LIST OF ACRONYMS'USED BMO Basis for Maintaining Operation CFR Code of Federal Regulation CR control room CS core spray.
EDCR-Engineering Design Change Request EDG emergency diesel generator ER Event Report FME foreign material exclusion GE General Electric GL Generic Letter HPCI high pressure coolant injection IFl Inspector follow item IN Iriformation Notice LCO Limiting Condition for Operation LER Licensee Event Report LPCI low pressure coolant injection MCC motor control center NNS Non-nuclear safety NRC Nuclear Regulatory Commission
'NRR Office of Nuclear Reactor Regulation PORC Plant Operations Review Committee QA Quality Assurance RHR residual heat removal RP radiation protection SER Safety Evaluation Report TS Technical Specifications UFSAR Updated Final Safety Analysis Report URI unresolved item VY Vermont Yankee l
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