IR 05000255/1997017
| ML18065B142 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 01/12/1998 |
| From: | James Gavula NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | |
| Shared Package | |
| ML18065B141 | List: |
| References | |
| 50-255-97-17, NUDOCS 9801200150 | |
| Download: ML18065B142 (8) | |
Text
U.S. NUCLEAR REGULATORY COMMISSION Docket No:
License No:
Report No:
Licensee:
Facility:
Location:
Dates:
Inspector:
Approved by:
9801200150 980112 PDR ADOCK 05000255 G
PDR REGION Ill 50-255 DPR-20 50-255/97017(DRS)
Consumers Power Company 212 West Michigan Avenue Jackson, Ml 49201 Palisades Nuclear Generating Plant 27780 Blue Start Memorial Highway Covert, MI, 49043-9530 December 1 O - 11, 1997 Martin J. Farber, Reactor Engineer, Riii James A. Gavula, Chief Engineering Specialists Branch 1 Division of Reactor Safety
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EXECUTIVE SUMMARY Palisades Nuclear Generating Plant NRC Inspection Report 50-255/97017(DRS)
This inspection was a follow-up to the Maintenance Rule Baseline Inspection conducted February 10 - March 20, 1997, which examined the licensee's implementation of 10 CFR 50.65,
"Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." The report covers a two-day on-site inspection by one regional inspecto Maintenance
An inspection follow-up item involving performance of periodic assessments, reliability-availability balances, and use of industry operating experience was close An inspection follow-up item regarding the acceptability of proposed changes to the reliability criterion for the reactor protection system was close An inspection follow-up item regarding an evaluation of the reactor protection system for classification as category (a)(1) was close The licensee properly addressed all open items that were identified during the Maintenance Rule Baseline Inspectio For the three additional systems reviewed, the maintenance rule program was adequately implemented and the systems were appropriately classified.
Report Details Introduction This inspection was a follow-up to the Maintenance Rule Baseline Inspection conducted February 10 - March 20, 1997, which examined the licensee's implementation of 10 CFR 50.65,
"Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants." The report covers a two-day on-site inspection by one regional inspecto II. Maintenance M2 Maintenance and Material Condition of Facilities and Equipment (92902)
M General System Review Scope The inspector conducted a review of maintenance rule performance for the High Pressure Air, Instrument Air, and Waste Gas systems to assess the effectiveness of program implementation for these system b.1'
Observations and Findings for the Instrument Air System lnstrur:nent air compressors A and C were classified (a)(2) ori August 18, 1997, after more than one year of monitoring under (a)(1) due to reliability problems. The inspector discussed compressor reliability with operators and the system engineer and was informed that reliability for these two compressors had been good over the past yea The inspector also examined problem reports and logs and determined that the record correlated with the operators' and system engineer's perceptions. On December 10, 1997, compressors A and C exhibited delays in breaker closure after the hand switch was operated; additionally, compressor A exhibited an unloader problem. At the close of the inspection, the cause for the electrical problem had not been identified although troubleshooting was in progress. Compressor C remained available for service; however, compressor A was removed from service to repair the unloader. The inspector noted that the electrical problem was a new issue but that the unloader was a recurrence. The Maintenance Rule Coordinator indicated that compressor A would be evaluated for classification as (a)(1) based on a potential repetitive maintenance preventable functional failure determination. The inspector considered this an acceptable course of actio Observations and Findings for the High Pressure Air System The high pressure air system was classified (a)(1) following problems, caused primarily by rust particles from the carbon steel piping, with the operation of air operated control valves. The inspector discussed the system's performance with the system engineer and the Maintenance Rule Coordinator, reviewed a listing of maintenance rule problem evaluations for the system, and reviewed the corrective action plan for the system. The
- corrective action plan was complex and comprehensive and was focused on reducing or eliminating rust accumulation in the system through reduction of water content, reduction of oil content, and filtration of rust particles. The major aspects of the plan involved improved monitoring, adjustments and repairs, and modifications. Goals established for the system will be monitored beginning May 1998, following completion of adjustments, repairs, and modifications. The goals appeared appropriate. A review of maintenance rule problem evaluations did not reveal any undetected functional failures. The inspector considered the management of the high pressure air system to be acceptable from a maintenance rule perspectiv Observations and Findings for the Waste Gas System Although no performance criteria were exceeded, the waste gas system was classified (a)(1) following a series flammable mixture occurrences in the waste gas decay tank The inspector discussed the system's performance with the system engineer and the Maintenance Rule Coordinator, reviewed a listing of maintenance rule problem evaluations for the system, and reviewed the corrective action plan for the system. A discussion with the system engineer revealed that the majority of the problems stemmed from a 1983 decision to operate the waste gas surge tank at a negative pressure rather than at the originally designed positive pressure. Operation at a negative pressur.e was intended to prevent gases from leaking out but was causing in-leakage of oxygen, through many of the waste gas system inputs. The action plan was comprehensive and involved repairs and hardware modifications, as well as operating the surge tank at a positive pressure. The goals established for the system appeared appropriate. Further, since changing the operation of the surge tank, there have been no occurrences of explosive mixtures in the de~y tanks. The inspector considered the management of the waste gas system to be acceptable from a maintenance rule perspectiv Conclusions The three systems reviewed were appropriately classified. The planned response to the recent instrument air compressors' problems appeared appropriate, as were the documented corrective actions for the high pressure air and waste gas systems. The maintenance rule program was adequately implemented with respect to these system MS Miscellaneous Maintenance Issues (92902)
M {Closed) IFI 50-255/97003-01a(DRS): Performance of (a)(3) Periodic Assessment The inspector reviewed Action Item Record A-CMT-97-058 and the Maintenance Rule
. Refueling Periodic Assessment, which was issued on November 14, 1997, and covered the period September 1, 1995, to March 31, 1997. The assessment addressed all of the aspects specified by the Nuclear Resource Management Council 93-01 guidance and required by 10 CFR 50.65(a)(3). The report was thorough and drew appropriate conclusions with regard to system performance, appropriateness of preventive maintenance, structure monitoring, removal of equipment from service while operating, and the overall performance of the maintenance rule program. This item is closed.
M8.2 (Closed) IFI 50-255/97003-01 b(DRS): Performing Reliability-Availability Balance The inspector reviewed Action Item Record A-CMT-97-059 and Section 6.0 of the Maintenance Rule Refueling Periodic Assessment discussed above. The balance was evaluated both qualitatively and quantitatively. The qualitative evaluation addressed those systems where performance criteria had been exceeded. The evaluation noted that in the majority of these cases, reliability criteria were exceeded. The licensee concluded that a relaxation of unavailability to improve reliability was unnecessary; corrective actions were expected to restore system performance without incurring additional unavailability. The quantitative evaluation involved comparing the risk associated with unavailability with the risk from unreliability. In most cases the risk from unavailability was smaller than the risk from reliability problems, indicating that preventive maintenance was not excessive. The inspector concluded that the reliability-availability balance had been properly addressed. This item is close M {Closed) IFI 50-255/97003-01c(DRS): Evaluation of Industry Operating Experience The inspector reviewed Action Item Record A-CMT-97-060 and Section 4.0 of the Maintenance Rule Refueling Periodic Assessment discussed above. The use of industry operating experience and its tie to the maintenance rule program at Palisades was evaluated. The evaluation was thorough and identified four cases where industry operating experience could have prevented a failure, had it been properly evaluate The evaluation also identified five improvement initiatives in the licensee's industry operating experience program. Implementation of these initiatives was in progress at the time of the follow-up inspection. This item is close M (Closed) IFI 50-255/97003-02(DRS): Evaluation of Proposed Reactor Protection System Reliability Criteria During the baseline inspection, the team was concerned that justification for a proposed change to the reliability criteria for the reactor protection system was not adequat Following the completion of the inspection, the licensee supplied a justification for raising the allowable number of maintenance preventable functional failures from 2 to The justification was based on an inventory of discrete components and generic component failure data from Institute of Electronics and Electrical Engineering Standard 500. This was weighted by the historical performance of the plant's reactor protection.
system. The analysis indicated that an expected failure rate was 8.5 failures per 24 months. Further evaluation resulted in the establishing of two reliability criteria based on
- "conservative" and "nonconservative" failures. Conservative equipment failures were considered as a trip of the entire reactor protection system or a single channel. This was set at less than 5 maintenance preventable functional failures per 24 month Nonconservative equipment failures were considered as a failure to trip by either the entire reactor protection system or a single channel. This was set at less than t_wo maintenance preventable functional failures per 24 months. These criteria placed a priority on failures to trip (nonconservative) while monitoring for other modes of system failures. The licensee's justification for the proposed change, coupled with the
establishing of new reliability criteria which monitored at the channel level, was considered acceptable. This item is close M {Closed) IFI 50-255/97003-03<DRS): Evaluation of Overall Reactor Protection System Maintenance Rule Classification During the baseline inspection, the team identified that a maintenance preventable functional failure had not been properly identified and that the reactor protection system had exceeded its reliability criterion. Three of the subsystems were classified as {a){1)
at the time of the baseline inspection. The team was concerned that the identification of an additional failure, coupled with three subsystems already classified as (a)(1 ), was indicative of overall system problems. The licensee had issued a condition report on January 31, 1997, which identified the same concern. In evaluating reactor protection system performance, the licensee noted that six of the failures were associated with two subsystems that were classified as (a)(1) and one failure was associated with a modification rather than an equipment failure. The evaluation concluded that the seven maintenance preventable functional failures did not reveal generic or common mode problems with the reactor protection system or subsystems. The inspector reviewed the failures and concurred with the evaluation. The inspector concluded that the expert panel's decision not to classify the entire reactor protection system as (a)(1) was acceptable. This item is close V. Management Meetings X1 Exit Meeting Summary On December 11, 1997, the inspector presented the inspection results to licensee management. The licensee acknowledged the findings presente The inspector asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identifie PARTIAL LIST OF PERSONS CONTACTED Licensee T. Bordine, Licensing Manager D. Engel, Licensing Engineer M. Holbein, Operations P. Pitcher, Operations T. Palmisano, Site Vice President L. Phillips, System Engineer K. Speicher, System Engineer T. Steffler, Operations E: Tiffany, Maintenance Rule Coordinator J. Wicks, Operations LIST OF INSPECTION PROCEDURES USED IP 62002 Inspection of Structures, Passive Components, and Civil Engineering Features at Nuclear Power Plants IP 62706 IP 92902 Maintenance Rule Maintenance Follow-up 50-255/97003-01 a(DRS)
50-255/97003-01 b(DRS)
. 50-255/97003-01 c(DRS)
50-255/97003-02(DRS)
50-255/97003-03(DRS)
LIST OF ITEMS CLOSED (a)(3) periodic assessment reliability-availability balance industry operating experience reactor protection system reliability criter overall reactor protection system maintenance rule classification LIST OF ACRONYMS USED DRS Division of Reactor Safety NRC Nuclear Regulatory Commission CFR Code of Federal Regulations
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PARTIAL LIST OF DOCUMENTS REVIEWED Action Item Record A-CMT-97-058 (periodic assessment)
Action Item Record A-CMT-97-059 (balancing reliability-availability)
Action Item Record A-CMT-97-060 (industry operating experience)
Action Item Record A-CMT-97-061 (RPS performance criteria)
Action Item Record A-CMT-97-062 (RPS (a)(1) review)
Maintenance Rule - Refueling Periodic Assessment, November 14, 1997 Condition Report C-PAL-97-0136A Condition Report C-PAL-97-01368 High Pressure Air system Maintenance Rule Evaluations, 12/10/97 Waste Gas system Maintenance Rule Evaluations, 12/10/97 Palisades Nuclear Plant Action Plan 46, "High Pressure Air System Improvement Plan," Revision 1, December 9, 1997 Palisades Nuclear Plant Action Plan 42, "Waste Gas System," Revision 1, December 9, 1997