IR 05000327/1998005
| ML20236H251 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 06/12/1998 |
| From: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML20236H235 | List: |
| References | |
| 50-327-98-05, 50-327-98-5, 50-328-98-05, 50-328-98-5, NUDOCS 9807070138 | |
| Download: ML20236H251 (18) | |
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U.S. NUCLEAR REGULATORY COMMISSION
REGION II
Docket Nos:
50-327, 50-328 License Nos:
50-327/98-05, 50-328/98-05 Licensee:
Tennessee Valley Authority-(TVA)
Facility:
Sequoyah Nuclear Plant Units 1 and 2 Location:
Sequoyah Access Road Hamilton County, TN 37379 Dates:
May 4
.8.
1998
' Inspectors:
S. Alexander, Reactor Engineer, NRR, Division of Reactor Controls and Human Factors (DRCH),
Quality Assurance, Vendor Inspection and Maintenance Branch
P. Fillion, Reactor Inspector, Region II Team--
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Leader
-.F. Gee.-Reactor Engineer NRR, DRCH, Instrumentation and Controls' Branch S. K. Mitra. Electrical Engineer NRR, Division of Engineering. Electrical Engineering Branch G. Cwalina Senior Operations Engineer, NRR, i
DRCH Accompanying Inspector: Julio Crespo, Quality Assurance Engineer Consejo de Sequridad Nuclear.. Spain (inspection E
observer)
Approved by:
Kerry D. Landis, Chief Engineering Branch Division of Reactor Safety Enclosure
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' 9807070138 990612 PDR ADOCK 05000327
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EXECUTIVE SUMMARY Sequoyah Nuclear Plant Units 1 and 2 NRC Inspection Report.50-327/98-05 and 50-328/98-05
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AnLinspection was conducted using the guidance of Temporary Instruction (TI)
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- 2515/137. Inspection of Medium-Voltage and Low-Voltage Power Circuit Breakers, issued March 1998._ The inspection team comprised Region II and Headquarters personnel. On-site inspection time was four days plus an exit meeting.
The switchgear and. surrounding areas were found in good material condition in a walkdown inspection with no deficiencies identified. (Section M2.1)
The team concluded that.the-circuit' breakers were performing well, but that
refurbishment was needed based on the age of the breakers and lack of any.
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. previous refurbishment during the 20 years of service.
The licensee.had initiated.recently a refurbishment ~ program.
(Section M2.2)
The' preventive maintenance procedures for the 6.9-kV.and 480-Vac breakers were
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. of'a type; appropriate to the circumstances and. included appropriate
- qualitative and.gilantitative acceptance criteria. The maintenance procedures.
especially after the -last. revision, were considered a strength.
At the same
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time,'a weakness existed in that there was no currently' approved procedure covering the' Type 0B-25 circuit breakers, which were used as battery output-
' breakers (total four breakers). ~ (Section M3.1)
- The: team's review of maintenance records for ten safety-related circuit
' breakers indicated that the program had been implemented..except that one
- record 'could 'not be located. -However, the licensee's self assessment found
.that possibly as many as.36 low-voltage breakers had overdue PMs. ' The self
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-assessment also identified the weakness of not having unique. identifiers on
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- 480-Vac circuit breakers to help track maintenance activities on individual.
circuit breakers.
(Section M3.2)
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lThe' team performed a detailed review of failures of medium-voltage circuit
' breakers over the last three years. A sample of failures on 480-Vac circuit
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-breakers was also reviewed. The team found that.the licensee's root-cause determinations and corrective actions met the requirements of Criterion XVI.
With regard to the root-cause' analysis for a breaker which failed in service
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'after refurbishment, the inspectors considered the analysis conscientious.
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- self critical and a good. example of a thorough root cause analysis. A I
weakness was identified with the usefulness of the computer data base of l
maintenance history in that key information had not been entered into'the data
base.-(Section M4.1)
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The' ream found that the-licensee was complying with 10 CFR 50.65, Maintenance Rule; with regard-to treatment of power circuit-breakers.
(Section M4.2)
With one: exception; the team concluded that the resolution of issues expressed in operating experience documents' Part 21 reports and vendor letters was
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good. A strength observed was the' tendency to expand the scope ' review for the
' documents beyond the minimum acceptable.
(Section M5.1)
- The' vendor interface program (i.e. periodic request for, and evaluation of,
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the. latest.information), as a program, was in concert with the-NRC position on vendor' interface as stated in GL 90-03. The team identified lack of an j
approved,7 formally. maintained vendor manual for the Type DB-25 circuit breakers and incomplete vendor. information for several circuit breaker types aas weaknesses in implementation of the program..(Section M5.2)
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The inspectors'found.that Sequoyah's procedure for commercial grade dedication provided adequate guidance'for the procurement and dedication of commercial grade material:with minor exceptions. _Sequoyah primarily procures safety-related breakers and repair parts from Appendix B' qualified suppliers.
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REPORT DETAILS-Summary of Plant Status Units 1 and 2 operated at power during the inspection period.
Introduction The focus was to verify the adequacy of licensee programs, procedures,
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training, equipment and supporting documentation for the. maintenance of medium-voltage and low-voltage power circuit breakers.
The overall scope of the inspection was defined in Temporary Instruction (TI) 2515/137. Inspection of Medium-Voltage and Low-Voltage Power Circuit Breakers, issued March '1998.
The 6.9-kV circuit breakers were Type HK manufactured by a company (ITE-Gould)
now owned by Asea Brown Boveri (ABB). the 480-Vac circuit breakers were Type
.DS manufactured by Westinghouse Electric Corporation, the reactor trip breakers were Westinghouse Type DB-50 and the.125-Vdc circuit breakers were
~ Westinghouse Type DB-25 and-(one) ABB-K-line Type.
During April 1998, the licensee performed a self-assessment which paid close attention to the areas covered by TI 2515/137. The report identified many strengths and weaknesses which the NRC team agreed were valid.
Specific findings of the self-assessment are discussed in various Sections of this report.
Maintenance-
- H2-Maintenance and Material Condition of Facilities and Equipment
'M2.1 Walkdown of Switchaear Areas
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Jnsoection'Scooe
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The team made a walkdown inspection'of the switchgear areas.
The
- inspection included the following switchgear:
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'6.9-kV safety-related switchgear of both units.
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Non-safety-related 6.9-kV.switchgear of Unit 1.
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480-Vac safety-related switchgear of Unit 1.
Start bus outdoor switchgear which was common to both units.
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At.the team's. request.-the licensee opened a few breaker compartment'
doors.to allow viewing.the interior compartment with the installed breaker.
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Observations and Findinas The switchgear and surrounding areas were found to be well maintained.
No broken or missing parts were observed, and paint was.in good
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condition. A relatively small number of deficiency tags were observed, and these were of minor significance.
The team questioned a deficiency tag _(C 207812) on a ground fault relay on 6.9-kV.non-safety-related unit board 1B compartment.8 for a normal supply breaker.
Later the team learned that the tag represented. work to replace the relay with a newer style relay, and that the installed relay was fully functional and capable of detecting ground faults as required.
.The team observed that 480-Vac safety-related circuit breakers had.
unique identifier labels affixed. These labels had been installed within the past year as part of corrective action for a violation involving alignment problems. The team observed that the start bus breakers had labels affixed indicating they had recently been refurbished by an off-site shop.
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Conclusions
The switchgear and surrounding areas were found in good material I
condition in a walkdown inspection with no deficiencies identified.
M2.2 Material Condition of Circuit Breakers a.
Insoection Scone
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The team evaluated the material condition of the circuit breakers.
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Observations and Findinas
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A review of failures of circuit breakers over the last three years did not indicate any particular trend or generic performance problem. The start bus circuit breakers which were rated for 15 kV (used in the
'6.9-kV system) and installed.in outdoor type switchgear were recently refurbished.
The licensee had initiated recently a program of refurbishment intended to. include at least all safety-related circuit breakers. The team observed that there had been no program of refurbishment since initial plant start-up 1981/1982. The age (greater than 20 years of service) of the circuit breakers indicated that refurbishment was needed because industry experience has shown that even if breakers have had relatively good performance in the past, breakers
.begin failing at higher rates due to age related degradation (primarily factory lubrication not normally renewed during preventive maintenance)
beginning typically in the 12 to 15 year age range.
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Conclusions'
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.The team concluded that the circuit br.eakers were performing well, but
that refurbishment was needed based on the age of the breakers and lack I
of any previous refurbishment during the over 20 years of service. The j
. licensee had initiated recently a refurbishment program.
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M3-Maintenance Procedures and Documentation M3.1 Maintenance Procedures for Power Circuit Breakers a:
Insnection Scone The team reviewed the preventive maintenance procedures for the medium-voltage and low-voltage power circuit breakers, The procedures were compared to the maintenance section of the manufacturer's instruction.
manuals. The procedures were reviewed in light of the team's knowledge:
of. good industry' practice for breaker maintenance, as.well as specific guidance,in TI 2515/137.'.These documents and concepts provided a framework for assessing the quality of the maintenance procedures.
The ul.timate.. acceptance criterion applied by-the team was that the -
procedures were of a type appropriate to the circumstances and included appropriate qualitative and quantitative acceptance criteria,; as stated
- in 10 CFR 50, Appendix B, Criterion V -Instructions, Procedures and Drawings.
The team reviewed DC control' voltage to verify that the. breaker operation was assured at minimum: operating voltage as specified in t.he vendor's manual:or minimum calculated voltage, whichever is the lowest.
b, Observations'and Findinas The team observed that-the maintenance procedures were clear, detailed,
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incorporated sign-offs on individual steps by craft persons.and overall-by' supervisors, and included Quality Control hold points. ~ Data sheets provided~a good record of the results of all measurements made and
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. breaker condition at time of maintenance.
The team found that
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iinsulation~ tests and contact resistance tests specified correct values.
The procedures specified functional' testing at reduced control voltage
.and breaker timing measurements for diagnostic purposes.
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'The procedure for 6.9-kV circuit breakers was MI-10.4, "6.9.kV Breaker Inspection," Revision 31,-dated May 4. 1998.
Revision 31 incorporated
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rather extensive changes as a result of findings from the self-assessment conducted.in April-1998.
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The team observed that MI-10.4. Step 6.3.16 which had been added in Revision 31 specified-determining the minimum control voltage at which the breaker would operate.
The team observed that this step did not specify whether the test voltage should be applied with a step function or ramped. _The team commented that applying a step function was the preferred method, and that ramping should be avoided. The licensee agreed-to consider adding a caution statement prior to this step. The team observed that MI-10.4. Steps 6.3.9 and 6.3.10 specified performing an insulation resistance test (megger)'on the control wiring, but did not speci.fy any acceptance criterion. The licensee revised the procedure to add a criterion.
.The procedure for the 480-Vac breakers was MI-10.5. " Westinghouse Type DS Breaker and Switchgear Maintenance." Revision 28.
The recent self assessment recommended that this procedure should be carefully reviewed against the manufacturer's instruction manual.
This review was ongoing at the time of this inspection. The team did not have comment on any specific step in this procedure.
The-licensee presented evidence that procedures MI-10.4 and MI-10.5 had been reviewed and annotated by a manufacturer's representative and an acknowledged independent breaker expert. Their comments had been incorporated into the procedure.
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A Problem Evaluation Report (PER)~ initiated on May 6.1998 identified that there was no preventive maintenance procedure covering the Type DB-25 circuit breakers, which were used as battery output breakers (total four breakers in the plant).
The team reviewed calculation SON-VD-VDC-1, 125-Vdc Vital Instrument Power System Design Verification. Revision 26. dated May 5.1998, which evaluated the minimum worst case dc voltage to trip and close switchgear breakers. The worst case trip voltage for both 6.9-kV and 480-Vac breakers is during load shedding.
The worst case close voltage for 6.9-kV breakers is at the end of a 4-hour station blackout event when the feeder breaker must be closed to re-energize the shutdown board.
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battery charger is available whenever the 480-Vac breaker close coils must operate.
The calculation showed that worst case dc trip coil t
voltage for the 6.9-kV and 480-Vac breakers was 98.9 Vdc and 98.6 Vdc respectively which exceeded the 70-Vdc minimum vendor required voltage.
The minimum worst case close coil voltage for the 6.9-kV breakers was 91.46 Vdc which exceeded the 90-Vdc minimum vendor required voltage.
The licensee's preventive maintenance procedure called for testing at minimum vendor required trip and close coil voltage.
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Conclusions l
The preventive maintenance procedures for the 6.9-kV and 480-Vac breakers were of a type appropriate to the circumstances and included appropriate qualitative and quantitative acceptance critaria.
Maintenance procedures, especially after the last revision, were considered a strength.
At the same time, a weakness existed in that l
there was no procedure covering the Type DB-25 circuit breakers, which l
were used as battery output breakers-(total four breakers).
M3.2 Review of Documentation to Confirm Implementation of the Maintenance Proaram l-a.
Insoection Scone The team selected a sample of eight safety-related circuit breakers by load and function. and requested preventive maintenance data sheets for the last two times the preventive maintenance was performed. The records were reviewed to determine whether the licensee's program in terms of the interval between maintenance and the scope of maintenance was implemented.
b.
Observations and Findinas Review of the selected sample of data sheets confirmed that the interval between preventive maintenance was equal to or less than the licensee's stated program.
For one of the selected breakers, the last preventive
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maintenance was performed in December 1995, but the documentation for the previous maintenance could not be retrieved from the files.
The circuit breaker manufacturers endorsed the licensee's maintenance interval in letters to the licensee.
The team reviewed these letters, and confirmed that conditions of endorsement were implemented.
The maintenance data sheets reviewed as part of the selected sample were complete according to the procedure and did not contain any anomalies.
The licensee's self assessment on circuit breaker maintenance performed in April 1998 identified that thirty-six 480-Vac breakers had either overdue preventive maintenance or records could not be located for the i
maintenance.
Some of these breakers were safety-related, and the
licensee performed a Technical Operability Evaluation for these.
The licensee *s self assessment identified as a problem that maintenance
on the 480-Vac circuit breakers had been tracked by switchgear
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compartment number rather than breaker serial number.
The lack of
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unique identifier-(serial number) and recording of that number on all j
maintenance records meant a certain ambiguity existed with regard to
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6 work performed on individual circuit breakers.
The licensee initiated a problem report (SO980393PER) to resolve this issue.
The team learned, and subsequently verified, that unique identifiers were affixed to the 480-Vac circuit breakers within the last year.
The licensee indicated that maintenance would be tracked by unique identification number in the future.
For a certain class of circuit breakers at Sequoyah. preventive maintenance is mandated by the Technical Specification.
The licensee stated that the problem of overdue maintenance described above did not apply to the Technical Specification mandated maintenance.
The team requested the records for two TS breakers, and these records confirmed that the maintenance had been done according to the program.
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Conclusions The team's review of maintenance records for ten safety-rele circuit breakers indicated that the program had been implemented, except that one record could not be located.
However, the licensee's self assessment found that possibly as many as 36 low-voltage breakers had overdue PMs.
The self assessment also identified the weakness of not having unique identifiers on 480-Vac circuit breakers to help track maintenance activities on individual circuit breakers.
M4 Maintenance Staff Knowledge and Performance M4.1 Root Cause Evaluation and Corrective Action for Circuit Breaker Failures a.
Insoection Scooe At the team's request the licensee provided a summary of corrective maintenance performed on circuit breakers since the beginning of 1995.
The team reviewed this report and discussed failures and corrective actions with the cognizant engineers. The basic requirement applying to this item of inspection was 10 CFR 50. Appendix B. Criterion XVI.
Corrective Action, b.
Observations and Findinas Seven failures of 6.9-kV breakers to close or trip on demand or spurious tripping occurred since the beginning of 1995. The first occurred in April 1996 and the last occurred in October 1997.
Each of the failures was due to a different cause.
One failure was due to a burned lockout relay, one failure was due to drilling of the front panel which caused a short-circuit on control wiring.
One additional failure was failure of one pole to close, resulting in single phasing of the load, caused by defective refurbishment work on a non-safety-related breaker.
The
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remaining failures' were attributed to problems with the originally furnished breakers.
The cause of these failures did'not indicate any
. generic problem with the 6.9-kV circuit breakers.
The team found cause determinations as documented on work requests and other documents to be
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satisfactory..
'One root cause analysis was' reviewed in detail, and the team's-observations and findings were_ as follows.
The inspectors reviewed
'Sequoyah's.~6.9 kV Start Bus 1A Alternate Feeder. Breaker 1614 Root Cause Analysis _ SON 970905PER.~ The breaker had been refurbished by Asea Brown Boveri in accordance with their June 20. 1996 proposal for non-safety rel_ated breakers and sent to Sequoyah on February.27, 1997.
Before placing the breaker in operation. Sequoyah performed post refurbishment-inspections.and tests and found the breaker failed to meet acceptance
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criteria for closing response time. ~ Maintenance personnel-adjusted opening / kickoff springs to bring the breaker into the required acceptance range.
The breaker was' installed in the 1A Start Bus: Breaker (1614 alternate feeder compartment on April 1. 1997 and placed in
. service. _ On April 6,1997. the breaker was removed from service after
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the licensee detected.a voltage imbalance and heard an " abnormal" noise Lemanating from the breaker. An examination revealed burned arcing contacts. An examination of the breaker performed by a. vendor representative revealed seven discrepancies. which were attributed to V
inadequate workmanship at the vendor refurbishment facility.
Sequoyah reviewers determ.ined that the-primary cause of the breaker failure was'the inadequate refurbishment.
However. Sequoyah also identified weaknesses within their own organization which contributed to
.the problems.
For example. Sequoyah did not specify adequate inspection
- in their contract for-the commercial grade refurbishment-program, did not provide adequate instructions for te' sting during the breaker installation and did not adequately' analyze.the purchase request' versus lthe vendor. proposal.
1The inspectors _ reviewed the root cause analysis and found it to be
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thorough and well documented.
In addition, although the primary responsibility _ appeared;to be_ inadequate vendor performance, the j
licensee'took the opportunity to critically examine its own processes-
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and procedures and identify areas for-improvement. The inspectors
. determined ~ that this evaluation was an example of a-thorough and self
' critical; root cause analysis and was considered a strength.
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Corrective' maintenance records since the beginn.ing.of 1995 for 480-Vac circuit breakers were reviewed. The total number of failures was not
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independently established by the team. At least four work orders
- representing failures were reviewed, and the root cause determination
'and corrective ' actions were satisfactory.
The list of breaker
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3 functional failures being maintained pursuant to the maintenance rule listed three functional failures of low-voltage circuit breakers This included reactor trip breakers.
In reviewing the summary report for circuit breaker maintenance, the team observed several weaknesses in the computer based system.
First, the-system was capable of generating summary reports showing only the problem statement and not the-actual work performed.
In addition, even this limited system was not~ used to full advantage in that the problem
~ tatement would often leave out key information useful for trending or s
other studies.
For example, the_ summary statement for several work rsquests simply'said: trouble shoot breaker.
The summary report had a data field for cause, but often this field was left blank.
To determine
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-the number of failures of circuit breakers, the team was forced to review many work requests which were retrieved from microfilmed records.
In:some cases even upon review of the full work _ request record it was difficult to' determine the actual problem, cause and corrective. action.
L The team was able to obtain the desired information missing from work L
requests from other sources such as associated problem reports or maintenance rule records.
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The team performed.a detailed review:of failures of medium-voltage
- circuit breakers over the last three years.
A sample of failures on 480 V circuit breakers was also reviewed. - The team found that the licensee's root cause determinations and corrective actions met the requirements of Criterion XVI.
With regard to the root cause analysis
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for a breaker which failed in service after refurbishment, the
. inspectors considered the analysis conscientious, self critical and a good example of a thorough root cause analysis. A weakness was
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identified with the usefulness of the computer data base of maintenance history'in that key information had not been entered into the data base.
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M4.2 Maintenance Rule Issues
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a. 'Insoection Scooe The team reviewed the licensees compliance with 10 CFR 50.65.
Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants, with regard to power circuit breakers, b.
Observations and Findinas The licensee defined an Electrical Distribution System for maintenance rule. purposes, which included incoming and tie circuit breaker _ _ _ _
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Individual load circuit breakers were considered part of the associated mechanical system.
The team found that the licensee had criteria and goals for circuit breakers that were commensurate with safety.
Circuit breakers were classified as 10 CFR 50.65(a)(2) status.
No system was classified as (a)(1) status as a result of circuit breaker failures.
The licensee maintained a list of circuit breaker functional failures. The team found that this list was consistent with failures identified through review of corrective maintenance work requests.
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Conclusions The team found that the licensee was complying with 10 CFR 50.65, Maintenance Rule, with regard to treatment of power circuit breakers.
MS Maintenance Organization and Administration M5.1 Review and Evaluation of Goeratina Exoerience Documents. Part 21 Reoorts and Vendor Letters a.
Insoection Scooe The team reviewed the licensee's resolution of all the NRC Information
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Notices and Bulletins and vendor letters listed in TI 2515/137 j
applicable to the type of switchgear in use. The team reviewed a sample
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of 10 CFR 21 Reports for resolution.
b.
Observations and Findinas l
With regard to low-voltage breakers with one exception the resolution i
of issues in operating experience documents was good. The exception was the resolution of NRC IN 93-85, " Problem with X-relay In DB and DHB-type Circuit Breakers Manufactured by Westinghouse." dated October 20.
1995.
The licensee's response to the IN was that Westinghouse planned to issue a Nuclear Safety Advisory Letter (NSAL) and send the NSAL to
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the applicable plants.
Since the licensee did not receive a copy of the NSAL. no actions were taken by the licensee.
But the team found that DB-25 breakers were used in safety-related applications, and therefore the IN should have been evaluated.
In general, the team found the licensee had performed well in the area of review and evaluation of generic communications related to circuit breakers. A particular strength observed was the tendency to expand the scope of operating experience documents beyond 'he specific model numbers mentioned in the communication.
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Conclusions With one exception' the team concluded that the. resolution of issues
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-expressed-in' operating experience documents Part 21 reports and vendor
. letters was good.~'A' strength observed _was the tendency to~ expand the scope review for the documents beyond the minimum acceptable.
. M5.2 Vendor Interface Proaram a.
Insoection Scone The team reviewed the licensee's vendor interface program. The team
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. reviewed-the licensee's response to NRC Generic Letter 90-03. Relaxation of Staff Position in Generic Letter 83-28. Item 2.2 Part 2 " Vendor Interface for Safety-Related Components"; and its Supplement 1. both of which promulgated the NRC Staff's position on vendor interface programs:
GL 90-03: required documented periodic contact with vendors of key'
. safety-related equipment.
Supplement 1 mentioned Electrical ~
Distribution system equipment.
b.
Observations and Findinas The licensee had a list of key safety-related, components-and a detailed vendor technical-manual list (VTM). The key safety-related components list included data fields for NPRDS nomenclature. TVA nomenclature.
system code'.. unique identifier. VTM. vendor.. technical documents and
. manufacturer's name.
The key components list and the VTM list were used
.together to make the periodic contacts to the vendors as committed to in
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response to the GLs mentioned in the-scope section.
The overall vendor. interface program as defined in controlling procedures was -a comprehensive well ' organized program.
The team
' identified some weaknesses in implementation of the program as described below.
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. Battery output breakers were listed on page 69 of the key safety-related
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For this equipment. only the data fields for NPRDS nomenclature and system code had data entered.
The other data fields
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stated! "not.found." There were four Type DB-25 and one K-line Type battery output breakers. These equipment were not listed in the VTM
.li_st. The' team observed that the battery output breakers were the only equipment on the final. key safety-related components list that had the
" unique identifier and VTH fields left blank. As stated elsewhere in
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this report, no procedure for preventive maintenance had been developed for-the battery output breakers. While that fact could not be completely _ explained. the team concluded that lack of a unique p
identifier and VTM. contributed to lack of a maintenance procedure.
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tean deduced that the situation with the battery output breakers was. an isolated case.
This was based on~the fact that it was the only equipment on the key safety-related components list that did not have a VTM indicated.
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Contacts to manufacturers were made with a form letter that did not specify.the exact equipmentLinstalled nor the specific manuals in possession of the licensee for which an update.was being requested. For l
example Westinghouse Electric Corporation was being contacted, but the-
contact letter did not mention DB-25 breakers. This method contributed
to some vendor manuals being incomplete.
Examples of incomplete vendor
- manuals.were.the; reactor. trip breakers. Type DS breaker and Type HK breakers.
The Type HK manual did not include information on the switchgear.. structure itself.
Some VTMs were arranged in such a manner that information would essentially be_" lost in the files".
In some cases. the wrong vendor location was being contacted when updating VTM information.
For example, the'ABB Sanford, FLA. location was being contacted about the Type HK circuit breakers rather than Florence, SC.
The' team observed that most of the weaknesses mentioned above were the
' direct result of not having equipment-knowledgeable persons involved in the contact phase of the vendor -interface program.
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Conclusions The vendor interface _ program (i.e. periodic request for, and evaluation of. the latest information), as'a program, was in concert with the NRC position on vendor interface as stated in GL 90-03.
The team identified
' lack of an approved,. forma'.ly maintained vendor manual for the Type DB-25 circuit breakers and incomplete or inaccurate vendor information for several circuit breaker types as weaknesses in implementation of the program.
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M81 Miscellaneous Maintenance Issues.
.M8.1 JCommercial Grade Dedication of Breaker Parts a. >Insoection Scoce
~ The inspection team reviewed the licensee's commercial grade dedication
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. procedure-and assessed its implementation with regard to the procurement of metal-clad circuit breakers and their replacement parts.
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.additiont the inspectors reviewed the licensee's self assessment with regard to the procurement and dedication of commercial grade parts for circuit breaker _.
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b.- Observations and Findinas
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Dedication Procedure The inspectors' reviewed Sequoyah procedure NEDP-8.
" Technical Evaluation for Procurement of Materials and Services."
L Revision 0. November 14. 1997. The procedure establishes the
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requirements to perform technical evaluations and. determine quality requirements for the specification and procurement of materials, equipment and.nonpersonal services. The scope of the procedure includes L
determination of technical requirements, critical characteristics. and
. method of acceptance for the_ procurement and~ dedication of commercial grade items (CGI)'for use as basic components.
Sequoyah can obtain commercial grade parts for use in safety-related applications by two methods. Parts which are identified as commercial grade. items procured with the intent to dedicate them for safety-related
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service are procured.as Quality Assurance (QA) Level 2.
In' addition.
=two other QA level parts may also be used: parts which are procured-commercial. grade, quality related (i.e., the item is used in a safety-related component but does not perform a safety function) are procured as 0A Level'3 and parts which are strictly commercial grade are procured as-QA Level 0.
At.Sequoyah. 0A Level 0 and 3 parts can be upgraded to 0A Level 2.
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The inspectors found.that NEDP-8 provided adequate guidance for'the
. procurement and dedication of commercial grade parts with three minor exception's.
First. Section 3.3.3. " Acceptance of Items (Materials.
Components. or Spare Parts)." lists the four acceptance methods specified in industry documents.
However. Method 2. " Commercial Grade Survey." did not include the NRC restrictions noted in Generic Letter 89-02. " Actions to. Improve the Detection'of Counterfeit and Fraudulently Marketed Products." The inspectors reviewed other plant
. procedures including 0AP2. " Procurement Document Control." and determined that they included sufficient controls to effectively implement the NRC restrictions.
Second, the definition of critical characteristic used by Sequoyah was different from that promoted by the NRC'in'10 CFR Part 21 in that it did not relate the critical
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characteristics to the item's safety function.
Lastly, the inspectors noted that the definition of. safety function included in NEDP-8 was limited to'the effect of failure of the item may have on the host l equipment or system. The inspectors noted that some parts may fail in such a'way as.to= impact adjacent components or systems.
Sequoyah personnel committed to review the procedure and implement appropriate
changes. Aside from these minor weaknesses, the inspectors had no further~ concerns.
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Dedication of Breaker Parts The inspectors questioned Sequoyah
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employees as to the extent of commercial grade dedication for metal clad
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13 circuit breakers and their associated parts.
The inspectors were told that Sequoyah primarily obtains the breakers and parts from qualified Appendix B suppliers with very little dedication.
The inspectors were provided with a list of procurement made since September 1996 for commodity code 5925 (Circuit Breakers and Their Repair Parts).
The inspectors noted that no breakers or parts were procured as OA Level 2 l
(commercial grade to be dedicated) items.
The inspector selected several items procured as 0A Level 3 or 0 to determine if any had been subsequently dedicated.
None of the selected items were identified as being dedicated.
The inspectors then asked the licensee to provide a list of all items associated with commodity code 5925 that had been procured as OA Level 2 in the past few years.
The printout provided to the inspectors showed a total of 11 items. A review of all 11 items showed them to be molded case circuit breakers and parts.
Seouovah Self Assessment The inspectors reviewed the Sequoyah Self Assessment (SA)
report SA-E&M-98-009. "Sequoyah Nuclear Plant (SON)
Medium and Low Voltage Circuit Breaker Program." with regard to commercial grade dedication issues.
The Sequoyah SA report stated that the majority of the breaker parts are procured as OA material.
No records are maintained for commercial grade dedication other than with a Form 575 that is used to obtain material from the store room.
The Sequoyah SA team obtained a list of approximately 25 items that had the potential for being upgraded and was able to identify only one item that had been dedicated a toggle link pin dedicated in 1990.
The inspectors reviewed documentation associated with this procurement and determined the part had been obtained from the original equipment manufacturer (OEM) as a OA Level 2 item and properly dedicated by Sequoyah. The inspector noted that Sequoyah had originally attempted to obtain the item as OA Level 1 but identified some concerns with the OEM's dedication practices.
Therefore. Sequoyah obtained the items as OA Level 2.
(Note:
Sequoyah subsequently was able to qualify the manufacturer with regard to this item and all current procurement are OA Level 1.)
While reviewing the documentation associated with the item, the inspectors noted that the item is listed in the Sequoyah parts system under commodity code 5315. " Nails. Keys. Pins." and not under code 5925 associated with circuit breakers, even though the part is unique to circuit breakers.
The listing of this part under a different commodity i
code than that reserved for circuit breakers caused the inspector to l
question the completeness of the self assessment review.
Discussions l
with Sequoyah personnel indicated that they had limited their review to l
commodity code 5925 items and they were unaware that items listed under i
other commodity codes may be used in S/R breakers.
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In order to attempt to gage the extent of the problem, the inspectors obtained a list of all items listed under commodity code 5925.
The inspectors found the lis: to be extensive and include such parts as bolts, angles, and anchors, as well as many others.
Based upon that review the inspector determined that it was unlikely that many other parts had been listed incorrectly.
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Conclusions The inspectors *rund that Sequoyah's proceduce for coarnercial grade dedication proviad adequate guidance for the procurement and dedication of commercial grade material with minor exceptions.
Sequoyah primarily procures safety related breakers and repair parts from Appendix B qualified suppliers.
(Section M8.1)
lianaaement Meetinas Exit Meeting Summary The team presented the inspection results to licensee management on May 8, 1998. The licensee management acknowledged the results as presented. The team did not handle any proprietary information during the inspection, and no proprietary information is included in this report.
./RTIAL LIST OF PERSONS CONTACTED
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Licensee
- M. Bajestani., Site Vice President
- C. Burton, Manager Engineering and Support
- E. Freeman, Maintenance and Modification Manager
- R. Harrington, Manager Maintenance Electrical Group (MEG)
- H. Lorek, Manager System Engineering
- R. Norton, Site Quality Manager
- R. Proffitt, Licensing Engineer
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- P. Sclas, Licensing Manager
- J. Valenti. Manager, Engineering o id Materials NRC and Other Organizations
- D. Starkey, Resider + Inspector
- S. Shah Nuclear Energy Institute Task rorce on Circuit Breakers
- Attended exit meeting
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INSPECTION PROCEDURES USED TI 2515/137 Inspection of Medium-Voltage and Low-Voltage Power Circuit Breakers ITEMS OPENED, CLOSED AND DISCUSSED None e
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