05000424/FIN-2013005-01
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Finding | |
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| Title | Failure to Meet the Conditions of TS LCO 3.8.4 |
| Description | A Green, self-revealing non-cited violation (NCV) of plant Technical Specification (TS) 3.8.4, DC Sources - Operating, was identified for failure to meet the conditions of TS limiting condition for operation (LCO) 3.8.4. Specifically, placing the 1AD1CA battery charger out of service during performance of the 18 month load test surveillance, concurrent with the failure of the 1AD1CB battery charger, caused the 1A train chargers to be unable to fulfill their specified safety function. As a result, the 1AD1 safety-related 1E 125 VDC source was inoperable. The 1AD1CB battery charger was repaired, functionally tested, and placed back in service. This violation was entered into the licensees corrective action program as condition report (CR) 735160. The finding was more than minor because it was associated with the equipment performance attribute of the mitigating systems cornerstone and it adversely 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, removing the 1AD1CA battery charger from service to conduct a 18 month load test while the 1AD1CB battery charger was not capable of performing its specified safety function resulted in the loss of a single train for greater than its TS allowed outage time. The inspector evaluated the finding in accordance with IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power, dated June 19, 2012. Since the inspectors answered Yes to the question A.3 of the Mitigating Systems Screening Questions, Does the finding represent an actual loss of function of at least a single Train for greater than its TS allowed outage time, a detailed risk evaluation was required. A detailed risk evaluation was performed by resident inspectors and reviewed by a regional senior reactor analyst in accordance IMC 0609 Appendix A guidance using the NRC Vogtle Standardized Plant Analysis Risk (SPAR) model and the NRC Saphire 8 risk analysis code. An SDP Module Condition Analysis was run with the Unit 1 A train battery chargers, 1AD1CA and 1AD1CB failed with no recovery allowed for a 14 hour1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br /> exposure period. The dominant sequence was a transient consisting of a reactor trip coincident with the common cause failure of auxiliary feed pumps (AFW) to run and the inability of an operator to restore main feedwater (MFW). The detailed risk evaluation determined that the risk due to the performance deficiency was an increase in core damage frequency (?CDF) of <1E-7/year, a GREEN finding of very low safety significance. Because the increase in ?CDF was <1E-7/year no external events analysis was required. The risk was mitigated by the availability of alternate trains of components and the short exposure period. The detailed risk evaluation was reviewed by a regional senior reactor analyst. The inspectors determined that the cause of this finding was related to the corrective action program (CAP) component of the problem identification and resolution (PI&R) cross-cutting area due to less-than-adequate problem evaluation techniques. Specifically, licensee failed to adequately investigate why the wires were rolled during initial functional testing. |
| Site: | Vogtle  |
|---|---|
| Report | IR 05000424/2013005 Section 1R19 |
| Date counted | Dec 31, 2013 (2013Q4) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71111.19 |
| Inspectors (proximate) | B Caballero D Hardage F Ehrhardt J Laughlin M Cain T Chandler |
| Violation of: | Technical Specification |
| CCA | P.2, Evaluation |
| INPO aspect | PI.2 |
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Finding - Vogtle - IR 05000424/2013005 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Vogtle) @ 2013Q4
Self-Identified List (Vogtle)
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