05000220/FIN-2013003-01
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Finding | |
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| Title | Failure to Follow Containment Isolation System Surveillance Procedure Resulting in Isolation of the Reactor Coolant Isolation Cooling System |
| Description | A self-revealing NCV of TS 5.4.1, Procedures, was identified at Unit 2 when a CENG instrumentation and control (I&C) technician did not properly implement procedure N2-ISP-LDS-Q010, Reactor Building General Area Temperature Instrument Channel Functional Test, Revision 00102. As a result, a residual heat removal (RHR)/reactor core isolation cooling (RCIC) isolation bypass switch was inadvertently left in the NORMAL position during surveillance testing resulting in an unplanned RCIC isolation. CENG entered this issue into their CAP as CR-2013-002461. Other corrective actions included performing a human performance stand down that reinforced use of human performance tools and the need to identify and mark critical steps during pre-job briefs, retraining the I&C technicians involved in the event on proper use of human performance error prevention techniques, and improving bypass switch verification steps for procedure N2-ISP-LDS-Q010 and other similar lead detection system surveillances procedures. This finding is more than minor because it is associated with the human performance attribute of the Mitigating Systems cornerstone 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, the inadvertent isolation rendered the RCIC system inoperable and unable to perform its function for approximately 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. Additionally, this finding is similar to example 4.b of IMC 0612, Appendix E, Examples of Minor issues, and is more than minor due to the procedural error leading to a plant transient, i.e. an unplanned RCIC isolation. This finding was evaluated in accordance with IMC 0609.04, Initial Characterization of Findings, and Exhibit 2 of IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, issued June 19, 2012. Unit 2 is a boiling-water reactor (BWR)-5, and as a result, RCIC is treated as having a separate high-pressure injection safety function. A detailed analysis was conducted using SAPHIRE version 8.0.8.0 and Unit 2 SPAR model 8.17. Using an exposure period of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and conservatively assuming no recovery of the failed equipment, this finding had a change in core damage frequency of low E-8. The dominant accident sequence was a grid-related loss of offsite power with a failure of Division III power and the failure to recover offsite power and the emergency diesel generators (EDGs) in 30 minutes. Since the change in core damage frequency was less than 1E-7, contributions from large early release and external event did not need to be considered. Therefore, this finding was of very low safety significance (Green). This finding has a cross-cutting aspect in the area of Human Performance, Work Practices, because the I&C technicians did not effectively employ self-checking and place-keeping when implementing the test procedure which directly contributed to the resulting procedural error. |
| Site: | Nine Mile Point  |
|---|---|
| Report | IR 05000220/2013003 Section 1R22 |
| Date counted | Jun 30, 2013 (2013Q2) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71111.22 |
| Inspectors (proximate) | J Lilliendahl P Kaufman D Schroeder K Kolaczyk B Haagensen A Rosebrook J Krafty J Laughlin B Dionne E Miller B Scrabeck |
| Violation of: | Technical Specification - Procedures Technical Specification |
| CCA | H.12, Avoid Complacency |
| INPO aspect | QA.4 |
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Finding - Nine Mile Point - IR 05000220/2013003 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Nine Mile Point) @ 2013Q2
Self-Identified List (Nine Mile Point)
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