ML20127B642
| ML20127B642 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 01/07/1993 |
| From: | Helwig D PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9301130027 | |
| Download: ML20127B642 (7) | |
Text
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10CFn2.201 u
PIIILADELPlilA ELECTRIC COMPANY LIMERICK GENERATING STATION P. O. BOX 2300 SANATOGA, PA 19464-2300 (215) 3271200, EXT, 3000 January 7,
1993 DAVID R HELWIG
,VfggSjgr Docket Nos.
50-352 50-353 License Nos. NPF-39 j
NPF-85 U.S. Nuclear Regulatory Commission ATTN:
Document Control Desk Washington, DC 20555
SUBJECT:
Limerick Generating Station, Units 1 and 2 Reply to a Notice of Violation NRC Combined Inspection Report Nos. 50-352/92-27 and 50-353/92-27 Attached is Philadelphia Electric Company's reply to Notices of Violation specifying two violations for Limerick Generating Station (LGS) Units 1 and 2 which were contained in the NRC Combined Inspection Report Nos. 50-352/92-27 and 50-353/92-27 dated December 7, 1992.
The cited violations involved failure to take adequate corrective action regarding procedural compliance, and failure to take prompt corrective actions regarding identified failures of check valves in the Reactor Core Isolation Cooling system.
The attachment to this letter provides a restatement of the violations followed by our reply.
If you have any questions or require additional information, please do not hes,itate to contact us.
Very truly yours, 12n1N O) a v
JLP/DCS:cah Attachment cc:
T.
T. Martin, Administrator, Region I, USNRC f[U { I T. J.
Kenny,-USNRC Senior Resident Inspector, LGS 9301130027 930107 is /j r
PDR ADOCK 05000352
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D. M.. Smith - 52C-7
- w/ attachment G. R. Rainey.- 52A-6
.w/ attachment W. G..MacFarland - 61A-ll W/ attachment' J.
Doering,-Jr. - ADMS-1
- w/ attachment r
R. W.
Boyce - ADM2-A w/ attachment J. A. Muntz - SSB3-1
. w/attachm'ent G. J. Madsen - SMB2-4 w/ attachment' J. B. Cotton - 53A-1 w/ attachment E. W.
Callan - SMB3-1 w/ attachment J. J. McElwain - SSB4-3 w/ attachment G. J. Beck-52A-5 w/ attachment NRB Chairman - 53A-1 w/ attachment Secretary, NCB - SlA-13 w/ attachment PA DER BRP Inspector - SMB2-4 w/ attachment Commitment Coordinator - 52A-5 w/ attachment i-i z
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Inspection Nos. 50-352/92-27 50-353/92-27 Reply to a Notice of Violation Violation A Restatement of the Violation 10 CPR 50 Appendix B, XVI, Corrective Action, states in part, "In the case of significant condition adverse to quality, measures (for corrective action) shall assure that the cause of the condition is determined and corrective action taken to preclude repetition."
Contrary to the above, the Licensee's corrective actions did not assure that the cause of a condition was determined and that corrective actions precluded repetition.
Specifically, on September 15 1992, after the performance of preventive maintenance on a Paul Monroe Electro-Hydraulically operated butterfly valve, HV-76-OllB, the inspector identified that the maintenance worker did not follow procedure IC-ll-00093 while precharging the valve's accumulator.
The maintenance worker did not fully understand the pressure / temperature graph for pressurizing the accumulator and continued working without clarification for the misunderstood portion of the procedure.
This is a similar event to violations 50-352/92-03-01 and 50-352/92-11-01, where maintenance workers did not fully understand portions of specified procedures and continued working causing-them to violate the procedures.
(On April 23, 1992 and July 2, 1992, PECo acknowledged these violations and responded, stating, " Full compliance was achieved on February 13, 1992 and again on April 23, 1992.")
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This is a Severity Level IV violation.
(Supplement I)
Response
Admission of Violation Philadelphia Electric Company acknowledges the violation.
Reason for the Violation The cause of the event on September 15, 1992, was procedural non-compliance due to the format of the temperature versus pressure graph and the maintenance technician's unfamiliarity with the procedure.
This was previously an Instrumentation and Controls (I&C) procedure.
Additionally, the technician did not-stop work when a procedural ambiguity was encountered.
Attachment Page 2 of 5 Inspection Nos. 50-352/92-27 50-353/92-27 Extensive corrective actions have been initiated and are continuing.
These corrective actions have included communication of management expectations, team meetings, continuing training, all hands meetings, increased management oversight, and increased worker involvement in the procedure process.
These corrective actions were not fully effective in precluding the September 15, 1992 event.
Corrective Actions and Results Achieved For the specific event on September 15, 1992, the workers reperformed the preventive maintenance task on butterfly valve HV-76-011B in accordance with procedure IC-11-00093 with the result being the accumulator pressurized within its specified tolerance.
A review was undertaken to determine why previous corrective actions did not prevent the September 15, 1992 event.
The results of our analysis indicate that the adverse trend has been reversed by the corrective actions taken in response to violations 50-352/92-03-01 and 50-352/92-11-01:
1.
Workers now routinely initiate procedure changes.
2.
Technical adherence-to procedures is improved.
3.
Workers display improved ownership of procedures and accountability for procedure use.
Corrective Actions Taken to Avoid Future Non-Compliance Previously initiated corrective actions will continue.
Additional emphasis will be placed on event analysis and trending.
Monthly Maintenance management meetings have been initiated to review events, analyze trends, monitor corrective action effectiveness and increase awareness by involving all Maintenance /I&C Supervision in a team process for collaborative improvement in the overall execution of maintenance.
Date When Full Compliance was Achieved Full compliance regarding preventive maintenance on butterfly valve HV-76-OllB was achieved on September 15, 1992, when workers reperformed the task in accordance with procedure IC-ll-00093 and achieved accumulator pressurization within specified tolerance.
Ongoing actions discussed in tha previous section will serve to achieve full worker procedure compliance.
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' Attachment' Page;3-ofi51 50-352/92-27:
Inspection Nos.:
. 50-353/92-27:
Reply to a Notice of-Violation
~ Violation B Restatement of the Violation 10 CPR Appendix B,-Criteria XVI, Corrective Action,"
requires that measures shall be established to assure that conditions. adverse to quality, such as-failures, malfunctions, deficiencies, deviations, defective material and equipment, and..
non-conformances are promptly identified andfcorrected.-
Contrary to the above the following; Reactor Core Isolation Cooling (RCIC) system valve-failures were identified by PECo butL not promptly corrected:
1.
Primary' containment isolation valve, 49-2F028, was identified to stick in'the-closed. position on September 3,-1991.-
No-corrective actions were taken until-questioned by theiNRC.
resident-inspector.
During troubleshooting activities on November 4,.1992, the valve stuck in the open position, preventing it;from performing its containment' isolation function.
2.
On November-20, 1991 the RCIC vacuum breaker valve 049-2018' was-identified to be sticking in the open position.
No corrective actions were taken until an additional ~similar valve' failure' occurred and was questioned by:the NRC: resident-inspectors.
This is a' Severity. Level IV violation.-(Supplement I)
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Response-Admission of Violation Philadelphia Electric Company. acknowledges theLviolation.
Reason for-the Violation The: reasons 1 for this' violation were-as follows:
a)
The ResponsibleLSystem' Manager'did not perceiveithat.the-benefit.of working on-the affected valves'(49-2F028 Land-
. '49 2018) - which were operable, outweighed the risk of-extended system' unavailability.
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b)--Timely and aggressive troubleshooting of valve 49 2F008 was-not performed commensurate with the valve's safety significance as a Primary Containment Isolation Valve (PCIV)..
This troubleshooting would have provided the System Manager with more. data upon which to base the decision of. corrective maintenance.
c)
The System Manager was unaware of the existence of 10CFR21 issues related to the Reactor Core Isolation-Cooling (RCIC).
System vacuum breaker valves.
Knowledge of the 10CFR21 issues may have affected the decision to postpone corrective maintenance for valve 49-2018.
Corrective Actions and Results Achieved The RCIC-system PCIV 49-2F028 was declared 1 inoperable'and the appropriate Technical Specifications (TS) action to isolate the Primary Containment penetration was taken.when the valve-was discovered to be stuck in the open po ition on November-4, 1992.
A RCIC system outage was scheduled to allow corrective:
maintenance on_ valve 49-2F028. ' Repair of the RCIC-Vacuum-Breaker-Check-Valves (including-49-2018)- was also included inithis outage.
Investigation revealed that corrosion product buildup caused-valve _49-2F028 to become stuck.in the open position.
On1 valve opening,<a ridge developed-in the corrosion build up.due to wear caused by disk chatter.
When the valve began:to-close,Jthe-edge:-
'of the disk became caught on the ridge preventing the spring
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assisted disk from_ fully closing.
The valve was disassembled andL cleaned.
The corrosion build up was removed:and the. inner surfaces: smoothed.
The disk 1was checked for= freedom-of-movement' and the valve was re-assembled.
The-PMT:LLRT was performed.
satisfactorily.
The four vacuum breaker: check valves were disassembled:and
. examined.- Problems with-two of the valves were' discovered, Valve 49-2018 exhibited a problem previously identifiedfin=a-10CFR21 notification.
In the 10CFR21 Report, the manufacturer =of L
the-check valves identified the possibility _of:-the valvepsticaing due to the hanger and hanger block being cast rather than machined.
In 'these ' valves, the valve-disk: fits in the hangers which rotates on the hanger block.
Because the parts were< cast, Ltheir surfaces.were rough and{the potentialEfor binding-existed.
-Althoughi his problem was only found inEvalvei49-2018,:the l.
t applicable-' parts-were> replaced--in all four vacuum-breaker check-U valves.-_The;other problem discovered.was-in valve' 49-2017.
Here,.the problem was similar to'that-'of valve: 49-2018-but 'was.
E due to a factory. assembly problem 1rather than.a. manufacturing
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-problem.- Following parts replacement.and.re-assembly,_the_ vacuum:-
breakers were tested in accordance with Surveillance l Test)(ST)J l!
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-Inspection Nos. 50-352/92-27; 50-353/92-27.
_ procedure;ST-4-049-952-2 "RCIC'Vacu'um Breaker Test."
There were no failures.
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Corrective Actions Taken to' Avoid Future'Non-Compliance The details of this event along with' lessons le'arned have:
been presented to System Managers during System Manager training.
This training stressed the need to ensure the proper balance between working on components requiring system outages and:-
allowing degraded-conditions to' exist until a scheduled' outage.
This training was completed on' December 21, 1992.
System Managers have had a clear expectation established regarding the.importance of performing timely troubleshooting't -
o get an accurate understanding of component conditions.
Thisswas-accomplished in a System Manager training seminar.
It-included ce 1
discussion of the capabilities of the accoustical specialists of the Duclear Maintenance Division in aiding in-the non-intrusivei troubleshooting of check valves.
This action was completed:on December 21, 1992.
The-System Managers will be provided with all future 10CFR21 notices received related to Limerick components.
This' action was l implemented on January 5, 1993.
Additionally, all. System Managers will be provided with a list.of Limerick components known to be affected by 10CFR21 notices received prior to January-5,-1993.
This action is expected to be completed by January.31, 1993.
These actions will allow for enhanced' awareness-of potentially degraded-components.
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-Date When-Full Compliance was Achieved Full compliance regarding corrective measures for valve 49-2F028.and 49-2018 was achieved on: November 14, 1992ffollowing-completion of all valve repairs and the return to. operability of.
the valves.
Ongoing actions discussed in the previousisection ensure full compliance with 10CFR Appendix B, Criteria-XVI.
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