05000263/FIN-2016010-01
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Finding | |
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| Title | Failure to Plan and Perform maintenance to Correct HPCI Oil Leak |
| Description | A self-revealing finding preliminarily determined to be of low to moderate safety significance (White), and an associated apparent violation of Technical Specification 5.4.1.a, were identified for the licensees failure to plan and perform maintenance affecting the safety-related high pressure coolant injection (HPCI) system in accordance with written documents appropriate to the circumstance as required by Regulatory Guide 1.33, Appendix A, Section 9, Procedures for Performing Maintenance. Specifically, improperly planned and performed pre-April 2005 maintenance initiated a crack in a safety-related HPCI oil pipe and, for numerous years, the licensee failed to perform maintenance to resolve repeated identification of HPCI oil leakage. These failures resulted in a sudden increase in oil leakage on March 22, 2016, extending the unavailability of HPCI during a maintenance window and causing a loss of safety function. The licensee documented the issue in the corrective action program (CAP) as CAP 1516361 prior to repairing the oil leak and restoring the HPCI safety function. The inspectors determined that the licensees failure to pre-plan and perform maintenance on safety-related equipment was a performance deficiency; the cause was reasonably within the licensees ability to foresee and correct; and should have been prevented. The inspectors determined the issue was more than minor because it adversely impacted the Mitigating Systems Cornerstone attribute of Equipment Performance, and affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). Specifically, improperly planned and performed 2005 maintenance initiated a crack in a safety-related HPCI oil pipe and, for numerous years, the licensee failed to perform maintenance to resolve repeated identification of HPCI oil leakage. These failures resulted in a sudden increase in oil leakage on March 22, 2016, extending the unavailability of HPCI during a maintenance window and causing a loss of safety function. The inspectors applied IMC 0609, Attachment 4, and IMC 0609, Appendix A, Exhibit 2, Section A, for Mitigating Systems to screen this finding and determined a detailed risk evaluation was required because the finding represented a loss of system and/or function. Therefore, a coordinated effort between inspection staff and regional Senior Reactor Analysts (SRAs) was required to arrive at an appropriate risk evaluation for the degraded condition that resulted from the finding. The SRA used the Monticello Standardized Plant Analysis Risk (SPAR) model, version 8.24 for the detailed risk evaluation. This evaluation concluded that the HPCI system was degraded for over 10 years and significantly degraded for approximately 4 months. The system is risk-important and is used to mitigate many internal and external initiating events. The total delta CDF for the 121 day portion of the exposure period is 3.8E6/yr., which is a finding of low to moderate safety significance (White). HPCI is an important high pressure injection system that is used to mitigate internal events, internal flooding, and internal fire events at Monticello. The inspectors determined the contributing cause that provided the most insight into the performance deficiency was associated with the cross-cutting area of Human Performance, Conservative Bias because licensee individuals failed to use decision-making practices that emphasize prudent choices over those that are simply allowable [H.14]. Specifically, licensee Operations and Engineering management did not ensure entry into formal evaluation processes to address a potentially degraded condition for the HPCI oil leaks. |
| Site: | Monticello  |
|---|---|
| Report | IR 05000263/2016010 Section 1R15 |
| Date counted | Sep 30, 2016 (2016Q3) |
| Type: | Violation: White |
| cornerstone | Mitigating Systems |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71111.15 |
| Inspectors (proximate) | D Krause K Riemer M Holmberg P Zurawskik Carringtonb Dickson |
| Violation of: | Technical Specification - Procedures |
| INPO aspect | |
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Finding - Monticello - IR 05000263/2016010 | |||||||||||||||||||||||||||||||||||
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Finding List (Monticello) @ 2016Q3
Self-Identified List (Monticello)
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