05000336/FIN-2015007-02
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Finding | |
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| Title | Failure to Provide 10 CFR 50.59 Evaluation for Interim Action Associated with Implementation of Operability Determination Procedure |
| Description | The team identified a Severity Level IV, non-cited violation (NCV) of Title 10 of the Code of Federal Regulations (10 CFR) 50.59, Changes, Tests, and Experiments, in that Dominion failed to perform a written evaluation to provide the bases for determining whether a change to the facility required a license amendment. Specifically, the team identified that contrary to 10 CFR 50.59, Dominion failed to properly evaluate operator compensatory actions to refill an oil bubbler on the C reactor building component cooling water (RBCCW) pump that was leaking oil at a rate that would have prevented the pump from meeting its design basis 30-day mission time. The team identified that contributing to this performance deficiency was that station procedure OP-AA-102, Attachment 1, Immediate Operability Determination Guidelines, Step 7.c., associated with the evaluation of oil and coolant leakage in order to establish operability for this type of degraded condition, incorrectly instructs the Dominion staff that the use of compensatory actions is acceptable without performing a formal operability determination. In accordance with the NRC Enforcement Policy Section 6.1, the team used IMC 0609 to inform the severity of this 10 CFR 50.59 violation. Per IMC 0609, the team determined that the finding required a detailed risk evaluation due to actual loss of function of at least a single train for greater than its TS allowed outage time. The Region I SRA identified that because the finding involved the C RBCCW pump function to run for its mission time, the only accident events adversely impacted are the LLOCA sequences. The condition was conservatively modeled assuming an exposure period of one year with the C RBCCW pump failure to run basic event set to True. The resultant change in risk was estimated at mid E-8, or very low safety significance (Green). The dominated risk sequences involve a LLOCA with the failure of the remaining RBCCW pumps due to common cause. Since the estimated risk increase was less than 1E-8, no additional evaluation of external events contribution or change in LERF was required. Accordingly, per Section 6.1.d of the NRC Enforcement Policy, the severity of the violation of 10 CFR 50.59 was determined to be Severity Level IV, as it resulted in conditions evaluated as having very low safety significance (Green) by the Significant Determination Process (SDP). There is no cross-cutting aspect associated with this violation as cross-cutting aspects are not assigned to traditional enforcement evaluations. |
| Site: | Millstone  |
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| Report | IR 05000336/2015007 Section 1R21 |
| Date counted | Jun 30, 2015 (2015Q2) |
| Type: | TEV: Severity level IV |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.21 |
| Inspectors (proximate) | G Morris J Ayala J Patel K Mangan L Mckown P Krohn S Pindale W Sherbin |
| Violation of: | 10 CFR 50.59 Technical Specification - Procedures Technical Specification |
| INPO aspect | |
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Finding - Millstone - IR 05000336/2015007 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Millstone) @ 2015Q2
Self-Identified List (Millstone)
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