IR 05000352/1998004

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Insp Repts 50-352/98-04 & 50-353/98-04 on 980519-0706. Violations Noted.Major Areas Inspected:Aspects of PECO Energy Operations,Engineering & Maint
ML20236X821
Person / Time
Site: Limerick  Constellation icon.png
Issue date: 08/05/1998
From:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20236X800 List:
References
50-352-98-04, 50-352-98-4, 50-353-98-04, 50-353-98-4, NUDOCS 9808100283
Download: ML20236X821 (44)


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l U.S. NUCLEAR REGULATORY COMMISSION REGION 1 Docket No License No NPF-39 NPF-85 Report No Licensee: PECO Energy Correspondence Control Desk P.O. Box 195 Wayne, PA 19087-0195 Facilities: Limerick Generating Station, Units 1 and 2 imation: Wayne, PA 19087-0195 Dates: May 19,1998, through July 6,1998 Inspectors: A. L. Burritt, Senior Resident inspector F. P. Bonnett, Resident inspector S. L. Hansell, Resident inspector S. T. Barr, Resident inspector (Acting)

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Approved by: Clifford Anderson, Chief Projects Branch 4 Division of Reactor Projects l

9808100283 980805 PDR ADOCK 05000352 G PDR

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EXECUTIVE SUMMARY Limerick Generating Station, Units 1 & 2 NRC inspection Report 50-362/98-04,50-353/98-04 This integrated inspection included aspects of PECO Energy operations, engineering, and maintenance. The report covers a 7-week period of resident inspectio Operations

  • Material and procedural deficiencies challenged control room operators et Unit 2 which delayed the diagnosis of the inadvertent initiation of the standby liquid control system. The response of the operators was adequate. The evaluation to address the impact of injecting sodium pentaborate into the reactor vessel along with the cleanup activities was acceptable. (Section 01.2)
  • Control room operators at Unit 1 performed overall reactor start-up activities well to complete refueling outage (1R07). The operators broad interpretation of a Note in the GP-2 procedure was corrected by operations management to allow the reactor core isolation cooling (RCIC) system tuning evolution. (Section O3.1).
  • A breakdown of several barriers in the work control process resulted in missed Technical Specification (TS) post-maintenance test (PMT) requirements for the 'A'

reactor protection system (RPS). Subsequent reir)y replacement in the 'B' RPS channel resulted in both channels being inoperable for approximately two and one-half hours. Once recognized, management implemented immediate corrective actions to comply with the TS requirements and address the work control process deficiencies. (Section 08.1)

  • The root cause evaluation for the missed RPS PMT was thorough and addresised the most probable root cause(s) for the event. Primarily, the review of the RPS work packages by the work control personnel and control room supervisor was less than adequeta in addition, the outage schedule review of the relay replacement activities was also Ic" than adequate. The RPS relay work order activities wera moved forward in the refuel outage schedule and did not provida adequate review time to determine the impact of the relay replacement on plant activities. (Section 08.1)

Maintenance

  • Overall, PECO performed the five-year emergency diesel generator (EDG) overhaul in a well-coordinated manner. The maintenance and modification work was planned, implemented, and supervised well. However, the inspector identified four examples of poor procedure use. These examples were cross-departmental, and while individually of minor safety significance and not subject to formal i enforcement, indicated an overall weakness in the PECO staff's procedural

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Executive Summary (cont'd)

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l * Overall, the root cause evaluation for the deficient testing of primary containment l isolation valves (PCIVs) was adequate; however, the corrective actions implemented l for testing deficiencies associated with numerous containment isolation valves werc

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weak. Interim corrective actions to address discrepancies that led to the missed testing were not implemented and the long term corrective action plan and implementation time-table were not established in a timely manner. Further, two l' recommendations by the generic review team were rejected without adequate bases. However following the inspection the licensee made a number of improvements in the corrective actions, including finalizing planned corrective l actions and establishing implementation goals. This licensee identified violation of Technical Specification 4.6.3.1, primary containment isolation valve surveillance requirements is being cited because corrective actions were weak and untimel (Section E8.3)

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  • A generic impact review which identified 10 additional valves at each unit that required additional testing to confirm operability was not timely. In addition, the subsequent valve testing problems were not reported in an licensee event repor This is a violation of 10 CFR 50.73, reporting requirements. Further, weaknesses were identified in the implementation of the PEP process that led to the missed LER and could lead to missed or untimely operability assessments. (Section E8.3)

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e 1 TABLE OF CONTENTS E X EC UTIV E S U M M A RY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii TAB L E O F C O NTE NTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv Summary of Plant Status ............................................1 1. O p e r a t i o n s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 01 Conduct of Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 01.1 General Comments (71707) ...........................1 01.2 Inadvertent Standby Liquid Control Injection into the Reactor

! -Unit 2..........................................2 03 Operations Procedures and Documentation . . . . . . . . . . . . . . . . . . . . . . 3 03.1 Reactor Startup - Unit 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 08 Miscellaneous Operations issues (90712) ...................... 4 08.1 (Closed) LER 50-352/1-98-006: Missed Post-Maintenance Test for an RPS Channel Relay Replacement ...................4 08.2 (Closed) VIO 50-352,353/98-02-03, Ineffective Corrective Actions Regarding the Control of Locked Valves and Devices . . . . . . . . . . 6 ll . M a int e n a n c e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 M1 Conduct of Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 M 1.1 General Comments on Maintenance Activities (62707) ........ 7 M1.2 General Comments on Surveillance Activities (61726) . . . . . . . . . 7 M1.3 Five-year Overhaul of Emergency Diesel Generator D14 . . . . . . . . .'8 M8 Miscellaneous Maintenance issues (92902) . ..........,........ 9 M8.1 (Closed) VIO 50-352,353/98-02-04, Deficiencies in Configuration Control When Returning tne Secondary Meteorological Tower to Service Following Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 M8.2 (Closed) VIO 50-352,353/97-10-03, Inadequate implementation of Locked-Valve Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 lll . E ng ine e ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 E8 Miscellaneous Engineering issues (92902) ..................... 10 E8.1 (Closed) IFl 50-352,353/95-19-01: Motor-operated Valve O ve rt o r q u e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 E8.2 (Closed) URI 50-352,353/97-10-05: Primary Containment isolation Valve Wiring Configuration Error . . . . . . . . . . . . . . . . . . . . . . . 11 E8.3 (Closed) URI 50-352,353/97-10-04: Inadequate Primary Containment Isolation Valve Testing ....................11 E8.4 (Closed) URI 50-352,353/96-201-01, Failure to Meet ASME NC A-3 8 61 and 3 8 6 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 l

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. Table of Contents (cont'd)

V. Ma nageme nt Meeting s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 X1 Exit Meeting Summ ary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

.X2 Pre-Decisional Enforcement Conference Summary. . . . . . . . . . . . . . . . . 15 ATTACHMENT Attachment 1 - Inspection Procedures Used-Items Opened, Closed, and Discussed

- List of Acronyms Used

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Report Details Summary of Plant Status 4

Unit 1 began this inspection period in the start-up mode of operations following the unit's seventh e.efueling outage. Operators made the reactor critical on May 18,1998,and power ascension activities were underway as this inspection period bega I May 25 Operators maintained power at 70% to effect repairs of the 1 A condensate pum May 29 Operators raised power and maintained it at 80% to replace a vibration probe j on the 1B reactor recirculation pump. Operators initiated power ascension )

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May 31 Operators maintained power at 90% due to problems with the #2 feedwater heater level controls. Operators raised power to 100% on June 5. Unit 1 i operated at 100% power for the remainder of the inspection period with the

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exception of brief power reductions to accommodate routine testin l Unit 2 began the inspection period operating at 100% powe May 29 Operators began reducing reactor power to shutdown the unit and begin the i safety relief valve maintenance ot tage (2M23).

June 3 An inadvertent actuation of the standby liquid control (SLC) system cauc6d the outage to be extende June 14 Operators made the reactor critica June 16 Operators synchronized the main generator to the grid ending the outag June 18 Operator raised reactor power to 100%. Unit 2 operated at 100% power for the remainder of the inspection period with the exception of brief power reductions to accommodate routine testin . Operations 01 Conduct of Operations'

01.1 General Comments (71707)

Using Inspection Procedure 71707, the inspectors conducted frequent reviews of ongoing plant operations, in general, PECO Energy's conduct of operations was

professional and focused on safety principles, l

1 Topical headings such as 01, M8, etc., are used in accordance with the NRC standardized reactor inspection report outline. Individual reports are not expected to address all outline topic . .

01.2 Inadvertent Standbv Liould Control iniection into the Reactor - Unit 2 Insoection Scope (71707)

On June 3, an inadvertent initiation of one standby liquid control (SLC) subsystem occurred. The unit was in cold shutdown (at 116*F) during maintenance outage (2M23) for replacement of several leaking main safety relief valves (SRVs). The inspectors evaluated the operators response to the event, the licensee's evaluations performed to address the effects of the sodium pentaborate injection, and the subsequent cleanup activitie Observations and Findinas At 9:20 a.m., Unit 2 operators found one of the three SLC pumps running, injecting into the reactor vessel. The operators were responding to a reactor water cleanup (RWCrJ) system isolation that occurred about six minutes prior to the discover Further, shortly before finding the running pump the SLC tank low level alarm had annunciated. Operators secured the SLC pump and isolated the injection line to the reactor pressure vessel (RPV). No alarms were identified on the redundant reactivity control system (RRCS) which automatically initiates the SLC syste Operators confirmed that no work activities were being performed on or in the vicinity of equipment associated with the SLC system and no other anomalous j conditions existe j The operators ability to identify the SLC initiation was impaired because the loss of continuity annunciator was already illuminated and the continuity status light was I not working properly, as a result of recurring equipment deficiency. Additionally, when operators referenced the alarm response cards for the RWCU isolation, a SLC '

initiation was not listed as a potential cause for a RWCU isolation. Consistent with licensees assessment, the inspector determined that operator actions were adequate based on plant condition Engineers estimated that 320 gallons of sodium pentaborate was injected over a six minute period. The peak boron concentration was 55 ppm. Reactor water conductivity levels reached 75 micro-mho/cm, exceeding the limit of less than 10 micro-mho/cm for cold shutdown conditions. Operators returned the RWCU system to service and began a feed and bleed procedure to clean-up the RP j Borated water was processed through the radwaste systems and discharged to the i river after being confirmed within discharge limits. After several days, reactor conductivity levels were restored to within normal technical specification values and boron concentration was reduced to less than 1 PPM. In addition, the SLC system was flushed and restored to the normal standby configuratio The licensee's evaluations determined that no adverse conditions were created between the sodium pentaborate and the reactor vessel and internals, carbon steel components, and the fuel. In addition, reactor operation with up to 1 PPM boron had no adverse impact on fuel reliability, reactivity management, or transient and i accident analysis, i

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The cause of the SLC initiation was determined to be electromagnetic interference (EMI) from operation of an safety relief valve (SRV) during post-maintenance .

testing. The operation of this component, that shares a common cable tray but is otherwise unrelated to the RRCS system, induced a signal to the RRCS system which caused the partial SLC actuation. Corrective actions were implemented to mitigate the potential for induced signals on all inputs to the RRCS cabinet prior to plant startup. The root cause evaluation and correctiva actions are further I addressed in NRC Inspection Report 50-352,353/98-0 l Conclusion i

Material and procedural deficiencies challenged control room operators at Unit 2 which delayed diagnosis of the inadvertent initiation of the standby liquid control system. The response of the operators was adequate. The evaluation to address the impact of injecting sodium pentaborate into the reactor vessel along with the cleanup activities was acceptabl O3 Operations Procedures and Documentation )

03.1 Reactor Startuo - Unit 1 1 l Insoection Scope (71707) l

The inspector observed portions of the control room activities during the Unit 1 reactor startup on May 18 through 21,1998. The reactor startup and main turbine i startup were the last major objectives to complete the seventh refueling outage at Unit 1 (1R07) which lasted 49 days. The inspector reviewed general procedure l (GP)-2, Normal Startup, and discussed various sections of the procedure with the !

control room staff and managemen j Observations and Findinas The control room staff made the reactor critical at 8:41 p.m., on May 18, then proceeded with plant heat-up per procedure GP-2. The operators stopped the heat-up and maintained reactor pressure at 135 psig using bypass valve override controls, to allow maintenance technicians to tune the reactor core injection cooling (RCIC) system governor controls. The operators did not want to exceed 150 psig i because procedural controls would require the licensee to prove the RCIC system l operable within the next 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> l l l l During the RCIC tuning evolution, the inspector noted that the operators were j broadly interpreting a Note in procedure GP-2. The Note, which the operators I demonstrated difficulty in locating in the GP-2, allowed the operators to control plant heat-up and pressurization rates when greater than 200 degrees by manually using bypass valves. The operators, however, were maintaining the plant stable at i 135 psig with three bypass valves to prevent having to perform TS required actions )

upon reaching 150 psig. Further, the inspector noted that the reactor operator I I

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periodically withdrew control rods, adding reactivity to the reactor which appeared contrary to stable plant operatio In discussions with operations management,it became evident that the intent of the Note as written in the procedure and the current operator application did not agre Operations management revised the Note through the procedure change proces The inspector determined that the operators broadly interpreted a Note to perform certain activities during the start-u Conclusion  !

I Control room operators at Unit 1 performed overall reactor start-up activities well to l complete refueling outage (1R07). The operators broad interpretation of a Note in '

the GP-2 procedure was corrected by operations management to allow the RCIC tuning evolutio Miscellaneous Operations issues (90712)

0.8.1 { Closed) LER 50-352/1-98-006: Missed Post-Maintenance Test for en RPS Channel j Relav Replacemen ' Scope LER 1-98-OO6 reported both reactor protection system (RPS) channels were inoperable as a result of not performing post-maintenance testing (PMT) on one channel prior to removing the other channel from service for maintenance. The inspector reviewed the cause and corrective actions for this issu Observation and Findinas On April 4 and 5,1998, instrumentation and control (l&C) technicians were performing work activities to replace agastat relays in the Unit 1 'A' RPS. The unit was shutdown with all control rods fully inserted for refueling outage (1R07). The relays affected the Technical Specification (TS) RPS manual scram channel and reactor mode switch operability. These inoperable functions were not recognized by the Work Control Supervisor (WCS), Control Room Supervisor (CRS), or the work group. On April 6,1998, at 9:00 a.m., after technicians completed the relay replacement but not having performed the required PMT, the WCS and CRS gave approval to replace relays in the 'B' RPS channel. TSs requires the operators to insert an RPS half scram within 12-hours of the inoperable condition. The missed PMTs on the 'A' RPS channel exceeded the 12-hours limit. In addition, the removal i of the 'B' RPS channel relays resulted in both channels being inoperable concurrently. Technicians completed the 'B' RPS channel PMT at 12:27 p.m. The clar.t condition, requiring the insertion of a manual half scram and the mode switcF q iocked in shutdown, existed for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and 27 minute f

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On the evening of April 6th, plant personnel identified the missed PMTs dunng a weekly RPS functional test. Due to an unexpected RPS alarm response, an in-depth look at RPS work activities identified the missed PMTs. The 'A' RPS channel relays were subsequently tested and declared operabl l Immediate corrective actions taken to address the problem were thorough and included the following:

  • Operations Management stopped the approval of new work orders until the Senior Manager Operations reviewed the event and discussed the ,

expectations with all senior reactor operator f2

  • A team was assembled to determine the RPS status and initiate corrective actions to restore the system to an operable conditio * A review was performed of all other relay replacement work activities to identify other potential operability concern >
  • l&C held a stand-down to discuss the event with all technicians and re-emphasize communications standards with the operations departmen * A manager was assigned to coordinate future relay replacement The inspectors performed an on-site review of PECO's root cause evaluation and corrective actions. PECO's evaluation was documented in performance enhancement program (PEP), 10008201. The initial review was thorough and addressed the most probable root cause(s) for the event. Primarily, the review of the RPS work packages by the work control personnel was less than adequate. The WCS did not review the work package details and was balancing multiple activities associated with the unit shutdown. The CRS reviewed only one relay replacement activity in the package, unaware that a total of five relays were being replaced

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under the same work order. In addition, the outage schedule review of the relay replacement activities was also less than adequate The RPS relay work order activities were moved to the first weekend two days prior to the start of the refueling outage. This did not provide adequate review time to determine the impact of the relay replacement on plant activitie The inspector determined the long term corrective actions, completed and planned, were adequate. Actions included a review of the planning process to ensure that l work activities impacting TS equipment have sufficient administrative controls in place, to address the actions needed to prevent WCS overload, and provide licensed j operator training to review the event details for future training considerations. The f inspector reviewed the corrective actions and sampled the agastat relay replacement work performed during the Unit 2 outage (2M23)in June to ensure the Unit 1 corrective actions were sufficient to prevent recurrence. No additional problems were note . O

The inspectors determined that the missed post maintenance test resulted in a violation of Technical Specification 3.3.1 Actions a. and b. 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 50-352/98- ,

04-01) Conclusion l

A breakdown of several barriers in the work contiol process resulted in missed j Technical Specification (TS) post-maintenance test (PMT) requirements for the 'A' {

reactor protection system (RPS). Subsequent relay replacement in the 'B' RPS channel resulted in both channels being inoperable for approximately two and one-half hours. Once recognized, management implemented immediate corrective actions to comply with the TS requirements and address the work control process deficiencie The root cause evaluation for the missed RPS PMT was thorough and addressed the most probable root cause(s) for the event. Primarily, the review of the RPS work packages by the work control personnel and control room supervisor was less than adeouate. In addition, the outage schedule review of the relay replacement activities was also less than adequate. The RPS relay work order activities were moved forward in the refuel outage schedule and did not provide adequate review time to determine the impact of the relay replacement on plant activitie .2 (Closed) VIO 50-352.353/98-02-03, Ineffective Corrective Actions Reaardino the Control of Locked Valves and Device This violation concerned NRC-identified deficiencies with the locking of a suppression pool hatch valve. The violation was a repetitive failure of PECO's control of locked valves and was indicative of ineffective corrective actions. PECO acknowledged the violation and attributed the cause of the event to poor human performance, recognizing that the training given in response to the previous violation focused on technique and expectations and would not have prevented the noted recurrence. Subsequent to the cited event, PECO further identified two additional examples of improperly locked valves and, as part of corrective actions taken, verified all other locked devices in the two units were properly locked. In addition to verifying the locked devices, other corrective actions cited by PECO in their reply letter included a supervisory briefing and the presentation of a video depicting proper methods to secure locked valves, both of which were to be conducted for all site personnel by June 18,1998. PECO initiated a human performance improvement initiative relative to performance modes and tools to address the longer-term human performance aspects of this type of event.

l The inspector conducted several plant tours to independently verify the proper locking of applicable valves and identified no discrepancies. The inspector also viewed the prepared video and reviewed the sign-off sheets of the site personnel who had seen the video as of June 18. The inspector determined the content of the video was good, but that, as of June 18, a number of maintenance technicians,

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who directly work with locked valves, had not yet seen the video, in addition, many plant operators, health physics technicians and site security personnel, among others, also had not seen the video. In discussions with site managers, the inspector determined that it was not PECO's intent that "all" site personnel view the video, only those involved in dealing with locked devices. Those applicable personnel that had not seen it as of June 18 were scheduled to see it in the short term, but at the end of the inspection period several of those personnel still had not seen the video. Despite the minor inaccuracies in the licensee's reply letter, the inspector concluded that PECO's response to this event was adequate. This item is close . Maintenance j i

M1 Conduct of Maintenance  !

M1.1 General Comments on Maintenance Activitir,s (62707)

I The inspectors observed selected maintenance activities to determir.e whether I approved procedures were in use, detats were adequate, technical specifications .l were satisfied, maintenance was perfctmed by knowledgeable personnel, and post-maintenance testing was appropriately complete The inspectors observed portions of the following work activities:

o Unit 1 - D14 5 year Overhaul, June 22 - July 1; e Common - B SGTS Pressure Controller work, June 30 - July 2; e Unit 1 - 1D RHR Preventative Maintenance Replacements of Agastat Relays and Power Supply Bus Work, July 1; e Unit 1 - CRD Flow Orifice Upgrade Installation, June 30; Observed maintenance activities were conducted well using approved procedures, and were completed with satisfactory results. Communications between the various work and support groups were good, and supervisor oversight was goo M1.2 General Comments on Surveillance Activities (61726)

The inspectors observed selected surveillance tests to determine whether approved procedures were in use, details were adequate, test instrumentation was properly calibrated and used, technical specifications were satisfied, testing was performed by knowledgeable personnel, and test results satisfied acceptance criteria or were properly dispositione '

The inspectors observed portions of the following surveillance activities:

I o Unit 1 - ST-6-071-306-1,"A" RPS Manual Functional Test,"- June 22; e Unit 1 - ST-6-092-114-1,"D14 24 Hour Endurance Test,"- June 30; e Common - ST-6-092-365-0," Inoperable Unit 1 Safeguard Power Supply Actions for Both Units," - June 30

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e Unit 2 - ST-6-076-250-2,"SGTS and RERS Flow Test,"- July 1; e Unit 1 - ST-2-042-628-1," ADS Reactor Low Level Functional Test,"

- July 1; Observed surveillance tests were conducted well using approved procedures, and were completed with satisfactory results. Communications between the various work and support groups were good, and supervisor oversight was goo 'M1.3 Five-vear Overhaul of Emeraency Diesel Generator D14 Insoection Scone (62707)

PECO maintenance technicians performed a scheduled five-year overhaul of the D14 emergency diesel generator (EDG). The inspector observed several related activities to determine whether approved procedures were in use, technical specifications were' satisfied, maintenance was performed by qualified personnel, and post-maintenance testing was appropriately complete Observations and Findinas -

The inspector determined that the overhaul work packages were planned well to provide for the proper coordination and imple' mentation of activities, which included planned maintenance and engineering modification activities. The work performed by l&C, electrical, and mechanical maintenance technicians was good and performed per the proper procedures. Maintenance supervision and management

provided clear and good oversight of the work activities. Control room operators maintained good awareness of the ongoing maintenance activities, complied with all relevant technical specifications, and conducted all required PMTs. Operators made conservative operability decisions, and maintenance technicians properly investigated and resolved problems that occurred during post-maintenance testing with a fuel injector and with an air start system check valv In spite of the overall good performance and coordination of the EDG overhaul by PECO, the inspector identified several cases of weak procedure adherence or usage by personnel associated with overhaul activities. Examples included:

e A contract employee spilled a small amount of oil about one yard from an l outside storm drain during the pumping of oil from the EDG sump. The spill was observed by Limerick engineering, maintenance, and security personnel, I yet no-one notified the CRS as required by procedure SE-7, " Pollution l' incident."

e Maintenance personnel were working outside the EDG structure on the f exhaust stack,'approximately 15 feet above ground level, without the use of l any fall protection as required by procedure IS&H 2-8, " Fall Protection."

e A fire system impairment (FSI) was in place for the D12 EDG room, adjacent to the D14 room, due to a failed UV detector. The FSI required an hourly i

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fire- watch, which was performed by site security personnel as part of their rounds. The inspector verified that the required fire-watch was being performed, yet site security was not aware of, nor were they specifically following the requirements of procedure AG-CG-12.1, " Actions for Fire Protection impairments." The ambiguities in procedural responsibilities and requirements resulted in the control room operators remaining in a TS regulatory action for seven days past the repair and return-to-service of the applicable UV detecto * During the performance of the required 24-hour operating run of the EDG, the inspector noted that the control noom copy of the procedure had not been initiated by operators as completed to the point of current use. The test had been in progress for over 12-hours. The licensed operator supervising the PMT could not confirm completion of the required procedure steps performed earlier, but explained that the equipment operator or the crew field supervisor would maintain a field copy of the procedure with the in-field steps properly initialed. The inspector found that neither the field supervisor nor the respective equipment operator had the field copy of the procedure; and the inspector found the procedure laying unattended on an a cabinet in a common room outside of the EDG rooms. The inspector concluded that the usage and control of this surveillance test procedure did not meet the intent of procedure A-C-79, " Procedure Adherence and Use,"

which requires steps of a procedure to be initialed on the master copy of the procedure by the control room operator or by the local equipment operator upon completion of the their portion of the procedur The inspector determined that these procedural failures were minor in nature and constituted a violation of minor significance and are not subject to formal enforcemen Conclusion Overall, PECO performed the five-year EDG overhaul in a well-coordinated manne The maintenance and modification work was planned, implemented, and supervised well. However, the inspector identified four examples of poor procedure us These examples were cross-departmental, and while individually of minor safety significance and not subject to formal enforcement, indicated an overall weakness in PECO staff's procedural adherence.

i M8 Miscellaneous Maintenance issues (92902)

M8.1 (Closed) VIO S0-352,353/98-02-04. Deficiencies in Configuration Control When Returnino the Secondarv Meteorological Tower to Service Followino Calibratio This violation involved the secondary meteorological tower being taken out of service so required calibrations of tower detectors could be performed by l&C technicians. Due to poor communications between the I&C technicians and Operations staff, control room operators returned the tower to a declared operable

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status, yet the tower actually remained inoperable for an additional month while repairs were made on a deficiency ioentified during the calibration activities. PECO determined the cause of the violation to be improper work order and surveillance testing procedure adherence by l&C technicians and work planners, which resulted in operators returning the tower to an operable status without knowing of the ongoing repair work. Corrective actions included: counseling of l&C supervisors and technicians on the need for procedural compliance concerning the identification of component deficiencies and communication with control room personnel; and the counseling of Operations supervision on the need for more detailed log entries for inoperable equipment so that adequate operability determinations can be made. The inspector interviewed several l&C technicians in the field and found their knowledge level adeauate concerning actions required if a component fails a surveillance test, and the inspector reviewed several weeks of control roorn logs and noted a sufficient level of detail of entries related to equipment deficiencies. The inspector thereby determined the licensee's actions to have been adequate, and this item is close M8.2 (Closed) VIO 50-352,353/97-10-03,Inadeouate implementation of Locked-Valve Control This violation concerned the failure of equipment operators, who had opened floor drains during winterization tasks, to correctly implement the locked-valves procedure. PECO staff attributed the causes of this violation to inadequate:

procedure guidance, plant labeling, and communications between the control room and the equipment operators. For corrective actions, PECO revised the winterization procedure, attached labels to floor drain plugs to remind operators to notify the control room prior to opening floor drains, and issued a site bulletin to review essential elements of proper communications. The inspector determined the .

response to the violation was acceptable and that PECO staff had implemented the I corrective actions. This item is close )

111. Engineering E8 Miscellaneous Engineering issues (92902)

E (Closed) IFl 50-352. 353/95-19-01: Motor-operated Valve Overtorau '

Limitorque Corporation recommends disassembly and inspection of motor-operated valve (MOV) actuators that have been subjected to greater than 120% of their published torque rating prior to returning the components to service. The licensee generally conforms to the guidance, but defers the inspections to a later date (i '

the next refueling outage) on a case-by-case basis. Appendix B of Specification NE-119, " Motor-Operated Valves Thrust / Torque Determination Methodology,"

contains a graded approach to disassembly / inspection depending on how much over the published rating a specific actuator has been operated. PECO justifies this ,

approach on the basis of considerable operating and maintenance experience in I which no damage to actuator worms, worm gears, or worm shafts has been identified in actuators that have been overtorqued from 121 to 202% of the

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. published ratings. The inspector verified that overtorqued actuators are identified and evaluated promptly, scheduled and tracked in the maintenance planning system, and inspected within a technically acceptable period of time. This item is close E8.2 (Closed) URI 50-352. 353/97-10-05:Primarv Containment isolation Valve Wirina Configuration Erro This issue was unresolved pending NRC review of the root cause and implementation of corrective actions. The licensee's evaluation found that mis-wired primary containment isolation valve (PCIV) closing circuits were consistent with the computerized wire termination data base and was a result of a design error

during plant construction which was not identified during the documentation reviews. . The data base review was expanded to include all safety-related valves and identified one additional valve deficiency. Both deficiencies were identical termination errors: using terminals 21 and 22 (standard for DC breaker configurations) instead of terminals 5 and 6 (standard for AC breaker configurations)

for the 42c contact field wire termination points.~ The two valves involved were the only two AC powered valves in the reactor core isolation cooling syste Technicians corrected the mis-wired closing circuits and engineering management concluded that this was an isolated problem as a result of an original design error that was subsequently transcribed into the computerized data base. The discrepancy remained undetected since original construction because of a testing deficiency addressed in Section E8.3 of this report. The data base review identified two additional discrepancies that were typographical errors only, since the associated valves were configured correctly. This non-repetitive, licensee-identified and corrected violation of 10 CFR 50 Appendix B Criterion Ill, " Design Control" is being treated as a Non-Cited Violation, consistent with Section Vll.B.1 of the NRC Enforcement Policy. (NCV 50-352/98-04-02)

E8.3 (Closed) URI 50-352. 353/97-10-04:Inadeauate Primarv Containment Isolation Valve Testina Insoection Scope During the investigation to determine the root cause of a primary containment isolation valve (PCIV) closing circuit configuration error (see Section E8.2), the PECO engineering staff identified a testing deficiency involving numerous PCIV control circuits. The inspector evaluated the root cause and implementation of corrective actions to resolve testing issues, Observations and Findinas in December 1997, the licensee identified that the PCIVs were not adequately tested while investigating the reason that a mis-wired PCIV was not identified during routine surveillance testing. Specifically, the control circuit in question contains two parallel paths; one for manual operation with thermal overload

. protection and the other for automatic isolation witn the thermal overload protection bypassed. Both these paths are energized during an automatic valve isolation. The

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. . _ . _ _ _ _ _ _ . _ _ . _ _ _ _ _ _ _ ._____

l

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I licensee identified that a failure of the 42c bypass contact could be masked by the proper operation of the valve via the thermally protected portion of the circui Therefore, the test did not verify that a containment isolation signal would fully close the valve with the thermal overload protection bypassed, as required by technical specifications. The circuit, as wired, would permit the closed limit switch l instead of the torque switch to stop valve motion during an automatic isolation if

.

the 42c bypass contact failed. Consequently, the valve may not close fully into the seat, creating the potential for leakage past this PCIV. However, all but one PCIV

. functioned correctly when properly tested and the licensee corrected this malfunctio Root Cause and Corrective Actions The licensee's evaluation found that the 42c contact had not been tested because the previous circuit reviews, including the relatively recent generic letter (GL) 96-01 review, relied on electrical schematic drawings which were inadequate to determine which contacts performed safety functions. The schematics in question indicated in l l the limit switch contact tables, that the limit switch was open when the valve was l 0% open rather than approximately 5% ope The inspector concluded that the licensee's schedule for implementing corrective l actions was not timely. The licensee's planned corrective actions included revising I

! the schematics to correct the limit switch development table and to add a clarifying

' note for the limit switch contacts. The licensee's plan to implement corrective actions, prior to the inspection, was scheduled to be developed by August 199 Based on interviews, the implementation schedule would have extended about a year.

l- The inspector concluded that the licensee's corrective actions were weak, in that, the licensee did not plan to implement interim corrective actions to prevent recurrence. The licensee believed the prints in question did not represent a significant vulnerability. The licensee reasoned that the work groups using the '

l prints were aware of the issue and typically would not rely on the limit switch table for activities such as establishing limit switch setpoints. The inspector expressed a concern that no interim plan was being implemented to compensate for the extended schedule to complete the corrective actions. Without either interim or permanent corrective actions implemented for the inaccurate schematics, additional errors could be made during activities such as design modifications or subsequent circuit reviews. The licensee, in response, agreed to post an engineering design change request against each of the applicable drawings by August 1998 to alert potential users of the drawing inaccurac The licensee established a cross-functional team of engineering personnel to review

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- potential generic concerns with inadequate testing of other logic circuits. The team determined through a broad review of general logic prints that all contacts were being tested. The team made two recommendations. First, to document the bases for all contacts in safety-related circuits not currently being tested. Second, to perform a detailed review of the control room emergency fresh air supply (CREFAS)

L ___ _ _ _

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system to assure that system testing is per requirements. The team felt the second recommendation necessary since this complex system had numerous untested contacts and logic system functional testing is not performed for this syste Engineering management, however, did not accept the teams recommendations stating that formalization of previous review documentation would detract focus from other areas such as performance monitoring, safety reviews, and self assessment activities. Engineering management also believed that the GL 96-01 review of CREFAS was thorough and dee The inspector determined that the licensee's reliance on the GL 96-01 review of CREFAS was weak since the GL review did not identify the PCIV testing deficienc The inspector also considered that the documentation activity would provide additional rigor in the review to ensure no additional testing discrepancies exis The licensee, following discussion of these concerns with the inspector, planned to (1) perform a CREFAS review by the end of July 1998, and based on the findings, (2) re-assess within several weeks the need for the additional documentation for contacts not tested in other logics circuit Technical Specification 4.6.3.2, requires that PCIVs be demonstrated operable at least once per 24 months, by verifying that on a containment isolation test signal each automatic isolation valve actuates to its isolation position (fully closed and torque seated). Since initial plant operation, this test has not been adequately performed for numerous containment isolation valves and is a violation. Although the licensee identified this issue in December 1997,it is being cited because the corrective actions and their implementation were weak and untimely. (VIO 50 352, 353/98-04-03)

Reoortability

)

During the licensee's evaluation for valves other than PCIVs which may not be adequately tested, additional discrepancies were found. Specifically, twenty valves,

{

ten at each unit were identified that receive automatic closure signal and if not fully {

shut could cause emergency makeup water to be diverted from injection into the {

reactor vessel following an accident. As a corrective measure to assure valve I operability, the licensee appropriately implemented testing within the time allowed by TS 4.0.3, and confirmed these valves functioned correctl The inspector identified that although the initial large population of valves not I appropriately tested were reported in an licensee event report (LER), the subsequent group of valves identified to have the same problems were not reported within 30 days, as required. The inspector found that weaknesses in the implementation of the PEP process led to not initiating an LER or supplementing the previously issued LER on related testing deficiencies. The PEP implementation weaknesses

! could also result in missed or untimely operability assessments. The licensee

!

initiated a PEP to address the missed LER ard plans to evaluate the existing operability and deportability review process controls and implement revisions as appropriate. In addition the licensee implemented interim measures to assure operability and deportability are appropriately addressed.10 CFR 50.73 requires, in

>

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part, that licensees shall submit an LER within 30 days for any condition prohibited by the plant's technical specifications. The licensees failure to report the inadequate technical specification required testing of twenty safety-related valves is a violation (VIO 50-352,353/98-04-04).

The inspector also noted an approximate 2 month delay to identify additional valves that required testing for operability. The licensee acknowledged that the timeliness of the operability review was inadequate but did not initiate a PEP to address the delay. The inspector questioned why a PEP was not generated and the experience assessment manager noted the recent operability review process enhancements and the overall heighten awareness by the licensees staff concernN the quality and timeliness of generic implications reviews and corrective action implementatio Conclusion Overall, the root cause evaluation was adequate, however, the corrective actions implemented for testing deficiencies associated with numerou.s containment isclation valves were weak. Interim corrective actions to address discrepancies that led to the missed testing were not implemented and the long term corrective action-plan and implementation time-table were not established in a timely manne Further, two recommendations by the generic review team were rejected without adequate bases. However following the inspection the licensee made a number of improvemiants in the corrective actions, including finalizing planned corrective actions and establishing implementation goals. - This licensee identified violation of Technical Specification 4.6.3.1, primary containment isolation valve surveillance requirements is being cited because corrective actions were weak and untimel The generic impact review which identified 10 additional valves at each unit that required additional testing to confirm operability was not timely. In addition, the subsequent valve testing problems were not reported in an licensee event repor This is a violation of 10 CFR 50.73, reporting requirements. Further weaknesses were identified in the implementation of the PEP process that led to the missed LER j and could lead to missed or untimely operability assessment ~ E8.4 (Closed) URI 50-352,353/96-201-01. Failure to Meet ASME NCA-3861 and 3862 This unresolved item concerned instances where PECO Energy received and accepted ASME Code, Section 111 items from material suppliers without the complete documentation required. Specifically, Paragraphs NCA-3861(b) and NCA-3862.1(b)

of Subsection NCA, Section lli of the ASME Code require that when the required chemical analyses, tests, examinations, heat treatment, etc., are subcontracted, the approved suppliers certification for the operations performed shall be furnished as an identified attachment to the certified material test report (CMTR). In several instances, the approved supplier certifications were not furnished with the CMTR and were not included in the document packag l

)

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. . Generally, PECO's position is that when purchasing components from an ASME I certified material organization, they have the sole responsibility as affirmed on the l required CMTR, tu assure the material attributes meet all code requirement q Further, that the certifications in question provide no additional value to ensuring l the integrity of the processes used nor would it be evident to receipt inspectors that

'

l all necessary analysis were performed in accordance with the code requirements based on a review the attached certifications, if included. Specifically, paragraph NCA-3861(b) states that the material organization shall transmit all certifications received from other material organizations or approved suppliers, to the purchaser at the time of shipment. PECO contends that the word " transmit", as applied in the paragraph above, does not strictly mean the original document must be attached and thus provides the flexibility to transcribe the data on to the CMTR which also affirms that the contents of the report are correct and accurate and that all test results and operations performed are in compliance with requirement '

Although PECO disagreed with the NRC's interpretation of the ASME code l requirements for documentation, they plan to submit a code inquiry to address issue. In the interim, PECO is implementing changes to the procurement process to assure that when material is receive in the future all documentation is include PECO plans to conform to the interpretation provided by the code committee which includes NRC membership. The inspector determined that the safety consequences for the examples of incomplete documentation previously identified are low since the materialinvolved met the applicable code requirements. Consequently, this failure constitutes a violation of minor significance and is not subject to formal enforcement actio V. Management Meetings X1 Exit Meeting Summary The inspector presented the inspection results to members of plant management at the conclusion of the inspection on July 15,1998. The plant manager acknowledged the inspectors' findings. The inspectors asked whether any materials examined during the inspection should be considered proprietary. No proprietary information was identifie X2 Pre-Decisional Enforcement Conference Summary On June 10,1998, a pre-decisional enforcement conference was held at the NRC region I office to discuss potential enforcement issues identified in inspection Reports 50-353/97-009and 50-352,353/98-002. The issues related to operability and corrective actions for repeat equipment failures associated with emergency diesel generators, a residual heat removal valve and a high pressure coolant I injection valve. Slides used in the licensee's presentation at the conference have

'

been included as Attachment A to this repor .

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ATTACHMENT 1 INSPECTION PROCEDURES USED IP 61726: Surveillance Observation

- IP 62707: Maintenance Observation IP 71707: Plant Operationc IP 90712: In-office Review of Written Reports IP 92902: Maintenance Follow-up IP 92903: Engineering Follow-up ITEMS OPENED, CLOSED, AND DISCUSSED Ooened VIO 50-352/98-04-03 Missed Surveillance Testing as a Result of Weak Corrective Action and Untimely implementatio (Section E8.3)

VIO 50-352,353/98-04-04 Failure to Report the inadequate Technical Specification Required Testing of Twenty Safety-Related Valve (Section E8.3)

Closed NCV 50-352/98-04-01 TS post-maintenance test requirements resulted in both channels of RPS being inoperable for approximately two and a half hours. (Section 08.1)

l VIO 50-352,353/98-02-03 Ineffective Corrective Actions Regarding the Cont ol of Lo:ked Valves and Devices. (Section 08.2)

l VIO 50-352,353/98-02-04 Deficiencies in Configuration Control When Returning the Secondary Meteorological Tower to Service Following Calibration. (Section M8.1)

'VIO 50-352,353/97-10-03 Inadequate implementation of Locked-Valve Control (Section M8.2) i URI 50-352,353/97-10-04 Inadequate Primary Containment Isolation Valve l Testing. (Section E8.3)

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URI 50-352,353/97-10-05 Primary Containment isolation Valve Wiring Configuration Error. (Section E8.2)

NCV 50-352/98-04-02 Primary Containment Isolation Valve Wiring Configuration Error. (Section E8.2)

URI 50-352,353/96-201-01 Failure to Meet ASME NCA-3861 and 386 ,

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(Section E8.4)

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Attachment 1 2 IFl 50-352,353/95-19-01 Motor-operated Valve (MOV) Overtorqu (Section E8.1)

LER 50-352/1-98-006 Missed Post Maintenance Test for an RPS Channel Relay Replacement. (Section 08.1)

Discussed None LIST OF ACRONYMS USED ASME American Society of Mechanical Engineers CFR Code of Federal Regulations CMTR Certified Material Test Report CREFAS Control Room Engineering Fresh Air System CRS Control Room Supervisor EDG Emergency Diesel Generator EMI Electromagnetic interference FSI Fire System Impairment GL Generic Letter l&C Instrumentation & Control IFl Inspection Follow-up item IR inspection Report LER Licensee Event Report LGS Limerick Generating Station NCV Non-Cited Violation NRC Nuclear Regulatory Commission l PECO PECO Energy PEP Performance Enhancement Process PCIV Primary Containment isolation Valve

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PMT Post-Maintenance Testing

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RCIC Reactor Core isolation Cooling RHR Residual Heat Removal RPS Reactor Protection System l RPV Reactor Pressure Vessel RRCS Redundant Reactivity Control System RWCU Reactor Water Clean-up SLC Standby Liquid Control SRV Safety Relief Valves ST Surveillance Test TS Technical Specification URI Unresolved item VIO Violation WCS Work Control Supervisor

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ATTACHMENT A PECO Energy Limerick Generating

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Pre-Decisional Conference US NRC RegionI June 10,1998

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PECO NUCLEAR

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PECO Nuclear Limerick Generating Station

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i Pre-Decisional Enforcement

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Conference

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US NRC Region I I June 10,1998

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+ Mr. Jerry Rainey President, PECO Nuclear Mr. Jim von Suskil Vice President, LGS .

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Mr. Bob Boyce Plant Manager, LGS Mr. Joe Grimes Director ofEngineering, LGS

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Presentation Format

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Introduction Jim von Suskil -

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Three Areas Identified sobsoyce !.

Joe Grimes

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D21 Dies' el Generator Fa'ilure

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PECO Energy Position JerryRainey

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Establish Troubleshooting Guideline ' and Initiated Training ~ -

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Enharreement of Operability -

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Determination Process '

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