IR 05000271/1999003

Insp Rept 50-271/99-03 on 990329-0509.Non-cited Violations Noted.Major Areas Inspected:Operations,Engineering, Maintenance,Plant Support & Review of Maint Rule Program Implementation

ML20195J740
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	06/14/1999
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
Shared Package
ML20195J727	List: IR 05000271/1999003 ML20195J722
References
50-271-99-03, 50-271-99-3, NUDOCS 9906210111
Download: ML20195J740 (14)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION I

Docket N Licensee N DPR-28 Report N '

Licensee: Vermont Yankee Nucleap4ker Corporation Facility: Vermont Yankee Nuclear Power Station

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Location: Vemon, Vermont Dates: March 29 - May 9,1999 Inspectors: Brian J. McDermott, Senior Resident inspector

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Edward C. Knutson, Resident inspector I Julian H. Williams, Sr. Operations Engineer 1 Approved by: Clifford J. Anderson, Chief j

Projects Branch 5 1

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Division of Reactor Projects

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9906210111 990614 PDR ADOCK 05000271 G PDR

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l EXECUTIVE SUMMARY Vermont Yankee (VY) Nuclear Power Station NRC Inspection Report 50-271/99-03

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This integrated inspection included aspects of licensee operathns, engineering, maintenance, and plant support. The report covers a six week period of routine resident inspector activities and a Region I specialist's review of VY's Maintenance Rule > Program implementatio Ooerations

• Appropriate control of safety system alignments, implementation of Technical Specification (TS) required actions, and adequate operability reviews for degraded equipment were noted during routine control room tour *

Shift supervision exercised conser/ative judgement by delaying a test of the standby liquid control system when the high pressure coolant injection system was inoperabl (Section 01.1)

• The NRC identified that a licensee procedure permitted a 24-hour delay in implementing TS requirements if missed or inadequate surveillance procedures were discovered. VY subsequently took interim actions to prevent ti is practice. The failure to provide an adequate procedure for surveillance testing is a violation of TS 6.5, Plant Operating Procedures. This Severity Level IV violation is being treated as a Non-Cited Violation, consistent with Appendix C of the NRC Enforcement Policy. (Section 08.1)

Maintenance a Good preparation and implementation were observed during corrective maintenance on a reactor protection system (RPS) relay. Maintenance personnel used a shop mock-up i to review the work plan, exercised appropriate precautions to preclude impacts on the remaining RPS channels, and completed the work in a timely manner. (Section M1.1)

• The surveillance testing performed on a core spray sub-system, an emergency diesel i generator, and the standby liquid control system were performed in accordance with plant procedures and satisfied Technical Specification requirements. The equipment was appropriately retumed to standby alignment following the testing. (Section M1.2)

• The licensee implemented the maintenance rule monitoring activities required for several equipment failures associated with the June 9,1998 reactor scram. Contributing to this event was a feedwater pump minimum flow valve failure; the minimum flow function has been the subject of a performance improvement plan since 1997. An inspector follow-up item was opened to review the effectiveness of VY's most recent revisions to the improvement plan corrective actions. (Section M1.3)

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Executive Summary (cont'd)

Enaineerina

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In May 1998, W identified an inspection was not performed of a valve repair using the examination method required by the ASME Code. W did use an alternative examination method, but the approval required by the ASME Code was not obtained prior to returning the valve to service. W's failure to follow the ASME Code requirement was reported in LER 98-018 as a violation o' TS 4.6.E and was entered into the licensee's corrective action system. This Severity Level IV violation is being treated as a Non-Cited Violation, consistent with Appendix C of the NRC Enforcement Policy. (Section E8.1)

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TABLE OF CONTENTS EXECUTIVE SUM MARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii TAB LE OF CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

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l . Ope ration s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 O1 Conduct of 0perations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 01.1 Observation of Routine Plant Operations . . . . . . . . . . . . . . . . . . . . . . 1 l 08 Miscellaneous Operations issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 08.1 24-hour Allowance for Missed Surveillances . . . . . . . . . . . . . . . . . . . . 2 l

l l I . M a i nten a n ce . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 M1 Conduct of Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 l M1.1 Maintenance Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 l M1.2 Surveillance Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 M1.3 Maintenance Rule implementation Review . ...................4 M8 Miscellaneous Maintenance issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 M8.1 Review of Open Items Related to Maintenance . . . . . . . . . . . . . . . . . 5

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l ll i. Enginee rin g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..... 6 E8 Miscellaneous Engineering issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 E Review of Open Items Related to Engineering . . . . . . . . . . . . . . . . . . 6 E8.2 In-office Review of LERs Related to Engineering ..... .......... 7 l V. M a nagement Meetings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 l X1 Exit M eeting S u mmary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1 ATTACHMENTS i

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Attachment 1 - List of Acronyms Used

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Attachment 2 - ltems Opened, Closed, or Discussed

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Report Details Summarv of Plant Status i

Throughout most of the inspection period, the Vermont Yankee (VY) plant was operated at 100% power. Minor power reductions were made to support routine surveillance testing during j this perio . Operations j

01 Conduct of Operationst O1.1 Observation of Routine Plant Ooerations Inspection Scoce (71707)

l The inspectors routinely toured the control room to assess the conduct of activities, verify I safety system alignments, and verify compliance with Technical Specification (TS) l Limiting Conditions for Operation (LCO). Equipment deficiencies identified in control room logs were reviewed, and discussed with shift supervision, to evaluate both the equipment condition discussed and the licensee's initial response to the issu ; Observations and Findinas l No problems were identified with the status of plant safety systems during the control room tours or review of Event Reports (ERs). A sample review of work orders and ERs !

found that the basis for operability of degraded equipment was adequately evaluated and i documente On April 28,1999, the inspector noted that the Shift Gupervisor delayed the performance of a standby liquid control (SLC) system quarterly surveillance when an unrelated I surveillance failure required operators to take the high pressure coolant injection (HPCI)

system out of service. Although the TSs allow the SLC and HPCI systems to be  ;

l inoperable at the same time (with only their individual LCO actions required), the Shift Supervisor made a conservative decision to limit the number of safety systems intentionally removed from servic Conclusions Appropriate control of safety system alignments, implementation of Technical Specification required actions, and adequate operability reviews for degraded equipment were noted during routine control room tours. Shift supervision exercised conservative judgement by delaying a test of the standby liquid control system when the high pressure coolant injection system was inoperabl ' 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 .

08 Miscellaneous Operations issues 08.1 24-hour Allowance for Missed Surveillances Inspection Scooe (71707)

During a review of an inservice test (IST) deficiency discussed in inspection Report 50-271/99-02, the inspector noted W had adopted a 24-hour administrative allowance to perform missed surveillances prior to entering the applicable TS Limiting Condition for Operation (LCO). Observations and Findinas 10 CFR 50.36 describes TS surveillance requirements as tests, calibrations, or - )

inspections to ensure that LCOs will be met. This requirement is reflected in the W l custom TS definition of " Surveillance Interval," which says these tests shall be performed j on the instrument, component, or system prior to being required to be operabl NRC Generic Letter 87-09 identified a line-item-improvement for Standard Technical Specifications that would allow a 24-hour grace period for performing missed surveillances when the allowable outage times of the action requirements are less than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Licensees were encouraged to propose TS changes consistent with the GL guidance, however these changes were voluntar ;

W administrative procedure AP 4000, " Surveillance Testing Program," Revision 19, allows a 24-hour administrative period, prior to entering a TS action statement, for the performance of a missed surveillance test or when there are questions about the adequacy of a surveillance procedure. The inspector detem1ined that W had incorporated the guidance provided in Generic Letter 87-09 without receiving a change to the TS to specifically allow this 24-hour delay of TS action requirement j TS 6.5, " Plant Operating Procedures," requires detailed procedures covering l surveillance and test requirements. TS surveillances are those tests required to I demonstrate compliance with LCOs. Licensees are required to implement remedial action permitted by the TS until the LCO can be satisfied. Contrary to the above, on October 29,1998, W implemented a surveillance program procedure that allowed operators to delay TS remedial actions. Specifically, AP 4000, Surveillance Testing Program, allowed a 24-hour delay in the implementation TS required remedial actions if a surveillance test was missed. This Severity Level IV violation is being treated as a Non-Cited Violation, consistent with Appendix C of the NRC Enforcement Policy. The issue was entered in W's corrective action program as ER 99-0507. (NCV 99-03-01:

Inadequate Surveillance Procedure Allows Delay in implementation of TS Required Actions)

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3 Conclusions The NRC identified that a licensee procedure permitted a 24-hour delay in implementing TS requirements if missed or inadequate surveillance procedures were discovered. VY subsequently took interim actions to prevent this practice. The failure to provide an adequate procedure for surveillance testing is a violation of TS 6.5, Plant Operating Procedures. This Severity Level IV violation is being treated as a Non-Cited Violation, consistent with Appendix C of the NRC Enforcement Polic IL Maintenance M1 Conduct of Maintenance M1.1 Maintenance Observations (62707)

The inspector observed portions of plant maintenance activities to verify that the correct parts and tools were utilized, the applicable industry code and Technical Specification requirements were satisfied, adequate measures were in place to ensure personnel safety and prevent damage to plant structures, systems, and components, and to ensure that equipment operability was verified upon completion of post maintenance testin The inspector observed all or portions of the following maintenance activities:

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Fuel bundle moves in the spent fuel pool, observed April 19

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Reactor protection system relay, auxiliary switch repair, observed April 15 Good preparation and implementation were observed during corrective maintenance on a reactor protection system (RPS) relay. Maintenance personnel used a shop mock-up l to review the work plan, exercised appropriate precautions to preclude impact on the '

remaining RPS channels, and completed the wcrk in a timely manne M1.2 Surveillance Observations (61726) )

The inspector observed portions of a surveillance test to verify proper calibration of test instrumentation, use of approved procedures, performance of work by qualified personnel, conformance to Limiting Conditions for Operations (LCOs), and correct post-test system restoratio .

Core spray system quarterly surveillance, OP 4123, observed April 13

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Emergency Diesel Generator fast start surveillance, OP 4126, observed April 22

. Standby Liquid Control system quarterly surveillance, OP 4114, observed April 29

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The surveillance testing performed on a core spray sub-system, an emergency diesel generator, and the standby liquid control system were performed in accordance with plant procedures and satisfied Technical Specification requirements. The equipment was appropriately returned to its standby alignment following the testin M1.3 Maintenance Rule lmolementation Review Insoection Scope (62707)

The inspector conducted a risk-informed, performance-based review of three equipment failures associated with the June 9,1998 reactor scram. VY's Maintenance Rule Program implementation was assessed by reviewing VY's evaluations of failures involving a "B" recirculation pump motor-generator bearing, the "A" feedwater regulating valve, and the "C" reactor feedwater pump minimum flow valv Observations and Findinos On June 9,1998, non safety-related equipment failures caused a forced power reduction, contributed to a reactor scram, and complicated operator response to the event (Refer to NRC Inspection Report 50-271/98-09 for additional detail). The inspector reviewed the following maintenance related failures which occurred during this event:

. A bearing in the "B" reactor recirculation pump motor-generator failed because of excessive wear. Although a preventative maintenance inspection had identified it was degraded, poor communication between licensee personnel resulted in the degraded bearing being re-installed. The bearing failure caused operators to perform an unplanned power reduction in order to take the motor-generator out of servic . The "A" feedwater regulating valve (FRV) failed to close as operators reduced power because a cap screw (foreign material) in the feedwater system became lodged in the valve internals. This failure prevented the FRV from performing its intended function of maintaining reactor vessel level control, caused a high reactor vessel water leve!, and resulted in a reactor scra . The "C" reactor feedwater pump minimum flow valve failed to open when required as operators attempted to restart the "C" feedwater pump. A bmken linkage prevented operation of the minimum flow valve, and resulted in the loss of the "C" reactor feedwater pump's function. This failure also triggered the simultaneous start attempt of two standby feedwater pumps, which subsequently resulted in a partial loss of the offsite power to safety-related buse Based on a review of maintenance rule data and discussions with the VY's maintenance rule coordinator, the inspector found that the licensee had completed the maintanance rule monitoring activities required by Maintenance Rule Program. VY's actions included a function and scope determination, a safety significance determination, and a functional i failure evaluatio I I

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The June 9,1998 failure of the "C" reactor feedwater pump minimum flow valve impacted the risk significant function of providing feedwater to the reactor. The reactor feedwater system has been in (a)(1) status since November 1997 because the system had exceeded its reliability performance criteria due to minimum flow valve functional failures. The inspector observed that W's planned corrective actions included replacement of the minimum flow valves during the 2001 refueling outage. Interim actions to improve valve performance are currently being considered for the 1999 refueling outage. Based on the risk significant function of reactor feedwater pumps, the inspector concluded the timeliness of this corrective action is important. An inspector follow-up item will be opened to track future NRC review of W's interim corrective action or their basis for deferral until the 2001 refueling outage. (IFl 99-03-02: Maintenance Rule Corrective Action For Feedwater Minimum Flow Valves) Conclusions

The licensee implemented the maintenance rule monitoring activities required for several equipment failures associated with the June 9,1998 reactor scram. Contributing to this event was a feedwater pump minimum flow valve failure; the minimum flow function has l been the subject of a performance improvement plan since 1997. An inspector follow-up item was opened to review the effectiveness of W's most recent revisions to the improvement plan corrective action M8 Miscellaneous Maintenance issues M8.1 Review of Ooen Items Related to Maintenance (62706,92720,92902)

The following open item was reviewed for closure based on a review of additional information from (Closed) IFl 97-81-02: Review of Maintenance Rulo Methodology for Establishing Performance Criteria This inspector follow-up item was opened to track further NRC review of W's methodology for establishing reliability performance measures. Although no problems were identified with W's methodology during the Maintenance Rule baseline inspection, the team considered W's approach uniqu Industry guidelines suggest that probabilistic risk assessment (PRA) data used to model equipment reliability also be used to set maintenance rule reliability performance measures. Maintenance preventable functional failures (MPFFs) are failures that should have been prevented by the performance of appropriate maintenance. Data on MPFFs is collected and is used by licensees to evaluate the actual performance of the structure, system, or component (SSC) against the established reliability performance measure However, equipment failure rates used in PRAs are frequently lower than those used in the MPFF reliability performance measures. This is because an MPFF is not necessarily a PRA functional failure (PRAFF). Many maintenance rule functions are not modeled in the PRA or would not be considered failures in the PR ___-

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W's approach is unique in that all equipment failures are considered, not just MPFFs,

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when evaluating the performance of SSCs. At W, the failure to perform a maintenance i rule function is designated as a Maintenance Rule Functional Failure, or MRFF. As a result of this approach, W's reliability performance measures were established using a higher failure rate than the PRA in order to prevent systems from unnecessarily exceeding performance goals. To insure that poor performance is not masked by this approach, W's program requires a monthly " risk review" of MRFFs. The review evaluates whether the MRFF corresponds to a component failure addressed by the PRA l

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and whether the failure is risk significant. SSCs are reviewed by the Expert Panel for (a)(1) status whenever the SSC exhibits more than one risk significant PRA functional fai!ure in a three year perio The inspector reviewed the monthly risk review reports for January 1998 through February 1999 and noted that several systems or functions were forwarded to the Expert Panel for revie Based upon this NRC review, the inspector concluded that W's methodology for establishing reliability performance measures and monitoring SSC performance was ,

acceptable and met the requirements of the Maintenance Rule. W's methodology is i conservative because it captures all functional failures for evaluation and monitors equipment reliability for consistency with PRA assurnptions. Therefore, this inspector follow-up item is close Ill. Engineering ,

l E8 Miscellaneous Engineering issues E8.1 Review of Open items Related to Enaineerina (92902)

The following open item was reviewed for closure based on a review of additional information from W and a sampling of the licensee's corrective actions where appropriat (Closed) URI 98-13-02: ASME Pre-Service inspection of MSIV Not Resolved Prior to Plant Startup On May 28,1998, W identified that an ASME-required visual inspection had not been performed for a repair to one main steam isolCon valve (MSIV) during the 1998 refueling outage. Based on the other types of examinations and testing that had been performed on the repair, W concluded that the valve was operable. W subsequently recognized that the missed inspection constituted a violation of TS 4.6.E and reported the condition to the NRC as required by 10 CFR 50.73. During review of the LER, the inspector noted that the issue had been identified prior to startup from the refueling outage; therefore, at the time of discovery, no code violation had occurred because the valve had not yet been required to perform any safety function. However, the LER did not address W's failure to appropriately resolve the condition prior to plant startu l

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W investigated this aspect of the problem (ER 98-2084) and determined that the cause was inadequate process control for ASME-related work. A contributing cause was an insufficient awareness of the approval requirements for use of attemate inspection techniques. Finally, a lack of follow-up by W personnel resulted in a missed opportunity to have corrected the problem prior to retuming the MSIV to servic As corrective action, W obtained approval from the American Nuclear Insurers inspector (ANil) for the attemate inspection method used during the outage in lieu of the missed visual inspection. Altemate inspection methods are allowed, when approved by the ANil, as provided for in ASME Code section IWA-2240, "Altemative Examination." This action brought the repair into compliance with the cod In addition, W is developing an ASME repair process procedure, and incorporating the lessons learned from this event into training for engineering support personnel. The inspector considered these actions reasonable measures to prevent recurrence. The inspector concluded that W's failure to recognize the condition prior to startup was j consequential to the weak controls for ASME-related work, rather than representing a weakness in the corrective action program, and therefore was not a violation of l regulatory requirement W submitted LER 98-018-01, "ASME Section XI Code VT-3 Examination not Completed Following Repair of Main Steam isolation Valve due to the Omission of Relevant

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Information from a Plant Work Order," to supplement the root cause and corrective l action information of the original LER. The inspector reviewed the supolemental LER and determined that the corrective actions were consistent with W's internal event report, ER 98-2084. Therefore, LER 98-018-01 is administratively close TS 4.6.E requires that W perform inservice inspection of safety-related components in accordance with the ASME Boiler and Pressure Vessel Code,Section XI (the Code).

Section IWA-4000, " Repair Procedures," subsection IWA-4600, " Examinations," of the Code states that, "The repair areas shall be examined to establish a new preservice I

record. The examination shall include the method that detected the flaw." Contrary to the above, on May 28,1998, W identified that a visual VT-3 inspection of main steam isolation valve V2-808 had not been performed following repair of defects that had been identified during the VT-3 as-found inspection. This Severity Level IV violation is being treated as a Non-Cited Violation, consistent with Appendix C of the NRC Enforcement Policy. (NCV 99-03-03: Missed ASME Pre-Service inspection of MSIV)

E8.2 in-office Review of LERs Related to Enaineerina (90712)

l An in-office review of select Licensee Event Reports (LERs) was performed during this inspection. The adequacy of the overall event description, immediate actions taken, cause determination, and corrective actions were considered during this review. The following LERs were closed:

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(Closed) LER 98-018-01: ASME Section XI Code VT-3 Examination not Completed Following Repair of Main Steam Isolation Valve due to the Omission of Relevant Information from a Plant Work Order This LER is associated with URI 98-13-02 and based on the review discussed in Section E8.1 of this report, the LER is administratively close (Closed) LER 99-002-00: Lack of Understanding of the Relationship Between TS Pump Flow Requirements and Flow Rates Credited in Analyses Results in Failure to Properly Test Core Spray Pump Discharge Check Valves The licensee identified and adequately resolved a discrepancy in the inservice test

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method used to verify the core spray pump check valves fully open during routine testing. This issue was addressed in NRC Inspection Report 50-271/99-02 and the failure to perform adequate testing was identified as a non-cited violation (NCV 50-271/99-02-01). This LER is close V. Management Meetings X1 Exit Meeting Summary l The resident inspectors met with licensee representatives periodically throughout the inspection and following the conclusion of the inspection on June 9,1999. At this meeting, the purpose and scope of the inspection was reviewed, and the preliminary findings were presented. The licensee acknowledged the preliminary inspection '

finding The inspector asked the licensee whether any material examined during the inspection should be considered proprietary, No proprietary information was identifie ,

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Attachment 1 I

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L!ST OF ACRONYMS USED BMO Basis for Maintaining Operation CFR Code of Federal Regulation CR control room CS core spray EDCR Engineering Design Change Request EDG emergency diesel generator i ER Event Report FME foreign material exclusion GE General Electric GL Generic Letter HPCl high pressure coolant injection IFl inspector follow item IN Information Notice LCO Limiting Condition for Operation LER Licensee Event Report LPCI low pressure coolant injection MCC motor control center NNS non-nuclear safety NRC Nuclear Regulatory Commission NRR Office of Nuclear Reactor Regulation PORC Plant Operations Review Committee QA Quality Assurance RHR residual heat removal RP radiation protection SER Safety Evaluation Report TS Technical Specifications UFSAR Updated Final Safety Analysis Report URI unresolved item VY Vermont Yankee A1-1

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Attachment 2 ITEMS OPENED, CLOSED, OR DISCUSSED l

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I IFl 99-03-02: Maintenance Rule Corrective Action For Feedwater Minimum Flow Valves (page

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l IFl 97-81-02: Review of Maintenance Rule Methodology for Establishing Performance Criteria l (page 5)

URI 98-13-02: ASME Pre-Service inspection of MSIV Not Resolved Prior to Plant Startup (ptge G)

LER 98-018-01: ASME Section XI Code VT-3 Examination not Completed Following Repair of Main Steam Isolation Valve due to the Omission of Relevant Information from a Plant l Work Order (page 8)

LER 99-002-00: Lack of Understanding of the Relationship Between TS Pump Flow

Requirements and Flow Rates Credited in Analyses Results in Failure to Properly Test Core Spray Pump Discharge Check Valves (page 8)

NON-CITED VIOLATIONS NCV 99-03-01: Inadequate Surveillance Procedure Allows Delay in implementation of TS Required Actions (page 2)

NCV 99-03-03: Missed ASME Pre-Service Inspection of MSIV (page 7) l

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