05000336/FIN-2013005-01
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Finding | |
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| Title | Implementation of NEI 99-01 Guidance |
| Description | A URI was identified because additional NRC review and evaluation was needed to determine whether Dominion adequately implemented the guidance of NUMARC NESP-007, Methodology for Development of EALs, to establish initiating conditions for two EALs applicable to Mode 6 operations. This is considered a URI because more information is needed, specifically the clarification and interpretation of existing guidance by the NRCs Office of Nuclear Security and Incident Response (NSIR), in order to determine if the issue constitutes a violation. During a review of both units EAL schemes, the NRC identified two EALs applicable in mode 6 during a loss of RHR flow when there was no direct RCS temperature indication (that was representative of core temperatures) available to determine if the initiating conditions had been met for an Unusual Event or an Alert. Upon discovery of this issue, the inspectors discussed it with staff from NSIR. The NSIR staff preliminarily indicated that this issue appeared to be an industry-wide generic issue in that there was a lack of specified instrumentation for assessing core temperature during refueling if there was a loss of RHR flow. Therefore, given the apparent lack of a specified standard to assess the initiating conditions for these EALs, the inspectors delayed pursuing enforcement action pertaining to Dominions adherence to 10 CFR 50.47(b)(4) and Sections IV.B and IV.C of Appendix E to 10 CFR Part 50. While assessing the adequacy of Dominions extent of condition review for two prior NCVs related to the operators ability to implement the EAL scheme, the inspectors identified two EALs applicable to both units during a loss of cooling flow while in Mode 6. During this condition, there was no direct indication available to determine if the initiating conditions had been met. Specifically, in Mode 6 during a loss of RHR flow there would also be a loss of core temperature indication because the only available instrumentation is in the RCS loops (With the vessel head removed, the core exit thermocouples are no longer available and there is no temperature indication for the refueling cavity). The initiating conditions for an Unusual Event ( Uncontrolled RCS temperature increase > 10F ) and an Alert ( Uncontrolled RCS temperature increase > 10F that results in RCS temperature > 200F ) cannot be assessed due to the loss of RHR flow through the core causing the instrumentation to become unrepresentative of actual core temperature. Upon discovery of this issue, the inspectors discussed it with NRC staff from NSIR. The NSIR staff preliminarily concluded that this issue appeared to be an industry-wide generic issue in that there was a lack of specified RCS core temperature indication during refueling if there is a loss of RHR flow. The inspectors will coordinate with NSIR to review the adequacy of Dominions implementation of the guidance in NEI 99-01. Pending review of this issue, this item is an Unresolved Item (URI 05000336/2013005- 01 and 05000423/2013005-01, Implementation of NEI 99-01 Guidance) |
| Site: | Millstone  |
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| Report | IR 05000336/2013005 Section 4OA2 |
| Date counted | Dec 31, 2013 (2013Q4) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71152 |
| Inspectors (proximate) | J Richmond P Presby R Mckinley R Rolph S Barr B Haagensen D Silk J Ambrosini J D'Antonio J Krafty |
| INPO aspect | |
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Finding - Millstone - IR 05000336/2013005 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Millstone) @ 2013Q4
Self-Identified List (Millstone)
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