05000317/FIN-2015001-02
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Finding | |
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| Title | Inadequate Risk Management Action for LOCI Sequencer Maintenance |
| Description | The inspectors identified a Green NCV of Title 10 of the Code of Federal Regulations (10 CFR) 50.65(a)(4) because Exelon did not implement adequate risk management actions (RMA) during the replacement of the loss of coolant incident (LOCI) sequencer for the safety-related 11 4KV [kilovolt] bus in accordance with station procedures. The inspectors determined that Exelons failure to establish adequate RMAs during the performance of LOCI sequencer maintenance activities in accordance with CNG-OP-4.01- 1000 is a performance deficiency. Exelons immediate corrective actions included entering this issue into their CAP as IR02444523 The inspectors reviewed IMC 0612, Appendix B, Issue Screening, and determined the issue is more than minor because it was associated with the procedure quality attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, without adequate RMAs per station procedure CNG-OP-4.01-1000, the capability of the 0C alternate alternating current (AAC) diesel generator (DG) to perform its safety function of powering the 11 4KV bus was adversely impacted. The inspectors also reviewed IMC 0612, Appendix E, Examples of Minor Issues, and noted that this issue is sufficiently similar to examples 7.e and 7.f, in that, Exelon was required, under plant procedures, to establish RMAs or additional RMAs. The inspectors, with the assistance of a Region I Senior Reactor Analyst, evaluated this finding using IMC 0609, Appendix K, Maintenance Risk Assessment and Risk Management Significance Determination Process, issued on May 19, 2005. Using Appendix K, Flowchart 2, Assessment of RMAs, the inspectors determined that the finding was of very low safety significance (Green) based upon the short duration exposure time (approximately one hour). Specifically, comparing the licensees calculated Yellow (1E-5) annualized risk for this maintenance evolution to the actual (1E-4/year X 1 year/8760 hours = 1E-8) incremental risk increase places the risk of this finding below the Incremental Core Damage Probability (ICDP) > 1E-6 threshold, resulting in a very low safety significance (Green). The inspectors determined that the finding has a cross-cutting aspect in the area of Human Performance, Work Management, because Exelon did not implement a process of planning, controlling, and executing work activities such that nuclear safety is the overriding priority. The work process includes the identification and management of risk commensurate to the work and the need for coordination with different groups or job activities. Specifically, Exelon failed to adequately plan, control, and execute the LOCI sequencer maintenance activity by establishing adequate RMAs that would have provided alternate success paths for maintaining the safety function of the out of service structures, systems, and components (SSCs) |
| Site: | Calvert Cliffs  |
|---|---|
| Report | IR 05000317/2015001 Section 1R15 |
| Date counted | Mar 31, 2015 (2015Q1) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.15 |
| Inspectors (proximate) | M Modes R Clagg S Horvitz D Schroeder E Burket E Torres H. Anagnostopoulus |
| Violation of: | 10 CFR 50.65(a)(4) 10 CFR 50.65 |
| CCA | H.5, Work Management |
| INPO aspect | WP.1 |
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Finding - Calvert Cliffs - IR 05000317/2015001 | ||||||||||||||||||||||||||||||||||||||
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Finding List (Calvert Cliffs) @ 2015Q1
Self-Identified List (Calvert Cliffs)
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