05000261/FIN-2010009-06
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Finding | |
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| Title | Adequacy of Emergency Operating Procedure Background Documents |
| Description | From interviews, the team determined that the control room operators, in responding to the event, relied exclusively on actions and guidance explicitly described in EOPs. The operators did not consider mitigating actions that would have stabilized the plant that were not explicitly contained in these procedures, such as shutting the MSIVs. The emergency procedures being implemented centered on the Path-1 EOP. From a review of the plant procedures used by operators to respond to this event, the team determined that certain Path-1 procedure steps required operators to rely on their knowledge because these steps did not contain detailed (rule-based) guidance. The team observed that Path-1 is a flow diagram that assists with diagnostics but does not consistently provide acceptance criteria and alternate actions. The team determined that, in general, implementation of the Path-1 EOP relies more heavily on operator knowledge-based behavior versus the rule-based behavior emphasized in WOG Emergency Response Guidelines. The team noted that common industry practice among Westinghouse technology plants is to utilize a two-column page format for EOPs and to also provide more explicit detail regarding specific parameters to be checked and specific components to manipulate within each step. The team observed that EOPs did not contain explicit guidance to fully isolate ongoing steam flow in all cases. For example, End Path Procedure (EPP) Foldout A Step 6 MSR Isolation Criteria does not contain additional contingency actions in the event the specified action cannot be taken or is not effective (i.e. loss of power to MSR steam supply valves). During interviews, operators stated that they had been trained in the simulator to send local operators to close MSR valves as a contingency action. However, this action is not listed in the Foldout A procedure and no additional or alternate action that could be performed from the control boards, such as closing the MSIVs, is specified. Additionally, Path-1 Turbine Tripped does not contain additional steps that operators might be reasonably expected to take in order to accomplish the intent of the step, such as closing the MSIVs, in the event that the specified contingency actions of manually tripping the turbine and running back the turbine are not successful. The team also identified an inconsistency between the Path-1 Basis Document and the licensees emergency operating procedure users guide regarding the immediate operator action of SI Initiation. Path-1 EOP does not explicitly list parameters or conditions to be checked in order to determine if a safety injection is required (requiring both the operator performing the immediate action and the CRS who is reading the procedure to rely on their knowledge). However, the Path-1 Basis Document provides an interpretation of this step that states, in part, that a safety injection is required if RCS inventory is decreasing in an uncontrolled manner and exceeding all available makeup flow. OMM-022, Emergency Operating Procedures Users Guide Section 8.3.1, Item 10, lists parameters and values that operators are expected to check when performing this immediate action step. The team noted that this step in OMM-022 does not specify checking RCS parameters directly related to RCS inventory, such as pressurizer level, as described in the Path-1 basis document. The team reviewed plant data from the first event and determined that pressurizer level decreased off-scale. Based on interviews, the team also determined that operators did not recognize the magnitude and rate of the pressurizer level decrease caused by the ongoing RCS cool down. Consequently, the team identified the need for additional NRC review to determine the adequacy of OMM-022 with respect to the immediate operator action of checking whether a safety injection is required. This review will determine whether the inconsistency between the Emergency Operating Procedures Users Guide and the Path-1 Basis Document is a performance deficiency. An Unresolved Item will be opened pending completion of this review. The URI is identified as 05000216/2010009- 06, Adequacy of Emergency Operating Procedure Background Documents. |
| Site: | Robinson  |
|---|---|
| Report | IR 05000261/2010009 Section 4OA5 |
| Date counted | Jun 30, 2010 (2010Q2) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 93800 |
| Inspectors (proximate) | J Hanna J Hickey L Miller L Wert P Fillion P Pieringer R Monk S Currie F Ehrhardta Nielsenc Kontz D Bollock D Mills G Laska G Skinner J Beavers J Brady J Hickey J Worosilo M Bates P Braxton R Musserr Monkf Ehrhardt J Hanna L Miller J Hickey P Fillion L Wert P Pieringer S Currie |
| INPO aspect | |
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Finding - Robinson - IR 05000261/2010009 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Robinson) @ 2010Q2
Self-Identified List (Robinson)
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