05000298/FIN-2016008-01
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Finding | |
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| Title | Possible Failure to Ensure that the Assumptions in the Engineering Analysis Remain Valid |
| Description | As part of the transition to a performance-based, risk-informed fire protection program, the licensee adopted the requirements of NFPA 805. NFPA 805 requires the following in Section 2.6: Monitoring. A monitoring program shall be established to ensure that the availability and reliability of the fire protection systems and features are maintained and to assess the performance of the fire protection program in meeting the performance criteria. Monitoring shall ensure that the assumptions in the engineering analysis remain valid. The team reviewed selected samples of equipment monitored by the licensee using Procedure 3-CNS-DC-357, NFPA 805 Monitoring Program, Revision 0, to ensure that the licensees program properly implemented the requirements of NFPA 805, Section 2.6. The team also reviewed Engineering Report Number ER2015-002, NFPA 805 Fire Protection Monitoring Program, Revision 2. The team observed that for components used in the fire probabilistic risk assessment, the unavailability time for those components was monitored using the existing maintenance rule monitoring program. These components included the: Control rod drive pumps Core spray pumps Emergency diesel generators Emergency station service transformer Startup station service transformer High pressure core spray pump Instrument air compressors Residual heat removal pumps Standby liquid control pumps Service water pumps The team noted that the action levels for availability in the maintenance rule monitoring program were greater than the assumptions in the fire probabilistic risk assessment. With this observation, the team questioned the licensee as to whether this met the requirement in NFPA 805 to maintain the assumptions in the engineering analysis. The licensee informed the team that they had performed a sensitivity analysis to determine the significance of monitoring at a higher level of unavailability via the maintenance rule. This analysis determined an increase in core damage frequency for the additional unavailability time that could be accrued above the assumption for availability in the fire probabilistic risk assessment and up to the maintenance rule monitoring value for unavailability. This increase in core damage frequency was then determined to be acceptable if it did not exceed 1.0E-6/year. The team noted that for an individual component this screening criterion would not exceed more than 2 percent of the licensees baseline fire core damage frequency. The team was aware that some particular aspects of the monitoring program were being discussed between the industry and the NRCs Office of Nuclear Reactor Regulation during periodic public meetings which discussed Frequently Asked Question 10-0059, NFPA 805 Monitoring. The monitoring program and the sensitivity analysis approach used by the licensee are enveloped in these discussions. The team determined that additional information is required to determine if a performance deficiency exists. Specifically, the team needed to determine if the licensees action to set the action levels for the availability of some plant components at the components maintenance rule monitoring values and the performance of a riskinformed sensitivity analysis in an attempt to ensure that the assumptions in the engineering analysis remained valid would be an acceptable approach. Judgment on the suitability of this approach is pending further resolution of the monitoring program during discussions of Frequently Asked Question 10-0059, NFPA 805 Monitoring. The licensee entered this issue of concern into the corrective action program as Condition Report CR-CNS-2016-05109. This issue of concern is being treated as Unresolved Item 05000298/2016008-01, Possible Failure to Ensure that the Assumptions in the Engineering Analysis Remain Valid. |
| Site: | Cooper  |
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| Report | IR 05000298/2016008 Section 1R05 |
| Date counted | Sep 30, 2016 (2016Q3) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.05 |
| Inspectors (proximate) | G Pick G Werner J Mateychick J Watkins P Lain R Deese S Alferink |
| INPO aspect | |
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Finding - Cooper - IR 05000298/2016008 | |||||||||||||||||||||||||||||||||||||||||
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Finding List (Cooper) @ 2016Q3
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