05000341/FIN-2007006-02
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Finding | |
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| Title | Undocumented Technical Basis for Change to EOP |
| Description | During one of the dynamic simulator scenarios, conditions were simulated during an Anticipated Transient Without Scram (ATWS) that required the operating crew to lower reactor pressure vessel (RPV) water level in accordance with emergency operating procedure (EOP) 29.100.01, Sheet 1A, RPV Control-ATWS. The purpose of lowering RPV water level is to reduce core inlet sub-cooling and thus reduce the potential for power oscillations. EOP 29.100.01, Sheet 1A, directs the operators to Terminate and Prevent all injection flow into the RPV except for flow from the CRD, Reactor Core Isolation Cooling (RCIC), and Standby Liquid Control (Boron) systems. Contrary to the BWR Owners Group (BWROG) Emergency Procedure Guidelines (EPG) and Severe Accident Guidelines [Revision 2] which states that failure to completely stop RPV injection flow (with the exception of CRD, RCIC, and Standby Liquid Control) would delay the reduction in core inlet sub-cooling, thus increasing the potential for flux oscillations the crew was observed to implement this step (FSL-10), in accordance with the licensees expectations, by turning OFF the low pressure Emergency Core Cooling Systems (ECCS) and Standby Feedwater pumps, reducing High Pressure Coolant Injection flow to 0 gpm, and reducing (i.e., NOT stopping) Feedwater system flow so that level decreased in a controlled manner. When asked why the licensees procedural steps deviated from the BWROG EPG, they stated that the deviation was necessary to allow time for bypassing of interlocks to prevent the loss of the Main Condenser heat sink, and to prevent dropping water level below the top of active fuel. The BWROG EPG states that reducing reactor power and preventing power oscillations is of greater importance than preventing loss of the main condenser. Technical Specification 5.4.1 requires, in part, that written procedures/instructions be established, implemented, and maintained covering the emergency operating procedures required to implement the requirements of NUREG-0737, Clarification of TMI Action Plan Requirements, and NUREG-0737, Supplement 1, as stated in Generic Letter 82-33. NUREG-0737 and the associated Supplement 1 required licensees to analyze transients and accidents, prepare emergency procedure technical guidelines, and develop symptom-based emergency operating procedures based on those technical guidelines. The BWROG EPG provides the technical basis for the development of the emergency operating procedures used by BWR licensees. Licensees are permitted to deviate from the BWROG guidelines provided they document the technical basis for the deviation. When asked to provide justification for the deviation from the BWROG EPG, the licensee was unable to do so. The licensee has initiated action (CARD 07-28195), through their corrective action program, to provide the necessary basis for the deviation. This issue is an Unresolved Item (URI) pending further NRC review and completion of the licensees actions to provide the necessary documentation to support the deviation: URI 05000341/2007006-02, Undocumented Technical Basis for Change to EOP ATWS Mitigation Strategy. |
| Site: | Fermi  |
|---|---|
| Report | IR 05000341/2007006 Section 1R11 |
| Date counted | Dec 31, 2007 (2007Q4) |
| Type: | URI: |
| cornerstone | No Cornerstone |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.11 |
| Inspectors (proximate) | J Cassidy T Steadham D Reeser J Rutkowski M Bielby M Franke R Morris R Telsont Steadhamd Reeser M Bielby M Franke R Morris A Wilson R Lerch K Barclay A Muniz C Lipa J Moore K Streit M Holmberg M Munir R Jickling J Cassidy |
| INPO aspect | |
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Finding - Fermi - IR 05000341/2007006 | |||||||||||||||||||||||||||||||||
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Finding List (Fermi) @ 2007Q4
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