05000458/FIN-2012009-03
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Finding | |
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| Title | Implementation Of The Procedure For Infrequently Performed Tests Or Evolutions |
| Description | The team identified an unresolved item associated with the licensees implementation of the guidance specified in procedure EN-OP-116, Infrequently Performed Tests or Evolutions, Revision 9. During the reactor startup which commenced on June 1, 2012, following the May 24 event, the operating crew received a safety relief valve acoustical monitor alarm when reactor pressure reached approximately 600 pounds per square inch (psig). The crew determined that two safety relief valves were leaking, and decided to hold reactor pressure at the current value in order to minimize the leak rate into the suppression pool. The licensee decided to cycle the safety relief valves open then closed in an attempt to reseat the valves. Based on vendor input, the licensee determined the valves should be cycled at 900 psig reactor pressure. The operators successfully cycled one safety relief valve, but the valve continued to leak. The licensee subsequently shut down on June 2 and cooled down the plant to implement repairs to the leaking valves. Since the cycling of relief valves is an activity not typically performed during startup, the operators appropriately decided the evolution would be performed using the guidance contained in procedure EN-OP-116, Infrequently Performed Tests or Evolutions, Revision 9. This procedure provides additional pre-planning steps and controls for use as an error prevention tool when conducting non-routine evolutions. The inspectors noted the following during the performance of the evolution: The approved pre-job brief checklist required the establishment of a list of potential problems and associated contingencies. A handwritten note indicated the only potential problem was an SRV sticks open. There was no associated contingency listed. The control room crew discussed this evolution and identified additional concerns such as: reactor pressure control with only one bypass valve approximately 20 percent open; reactor level control at low power; reactor power response with power on range 8-10 of the Intermediate Range Monitors; safety relief valve leak rate increasing with increasing reactor pressure; and the length of time the valve should be left open before being shut. The inspectors concluded the pre-plan developed from the Infrequently Performed Tests or Evolutions procedure did not comprehensively address potential problems associated with the cycling of safety relief valves. The controlling document for performing the cycling of the safety relief valves was procedure AOP-0035, Safety Relief Valve Stuck Open. However, because this procedure was written assuming the reactor was in Mode 1, the bulk of the guidance was not applicable to the situation faced by the crew. Consequently, over the course of the morning, several discussions were held among the operators on how to set up the initial conditions for the evolution as well as defining the abort and contingency criteria. The discussions concerning initial conditions and abort criteria continued up to the point when the safety relief valve was opened. The Infrequently Performed Tests or Evolutions procedure required plant system or component initial conditions to be identified. The operating crew concerns discussed above were not addressed by the controlling pre-plan developed from the Infrequently Performed Tests or Evolutions procedure and, consequently, the crew established and implemented the initial conditions. For example, the pre-plan document did not address reactor power or initial bypass valve position, so the operators withdrew control rods to increase reactor power and isolated various steam drain valves and other house loads. These actions were performed to open the turbine bypass valves further for adequate pressure control when cycling the safety relief valves. The inspectors determined the conditions established and the actions taken by the operators were appropriate. The inspectors determined the operating crew was effective in looking ahead and considering the different variables that could lead to an undesired transient; however, these actions the crews took in response to existing conditions rather than through a specific controlling pre-plan, developed using the Infrequently Performed Tests or Evolutions procedure. The inspectors concluded that although the procedure was appropriately referenced, it did not appear to have been effectively implemented for its intended purpose. The team concluded additional inspection is required to assess the effectiveness of the licensees use of the Infrequently Performed Tests or Evolutions Procedure |
| Site: | River Bend  |
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| Report | IR 05000458/2012009 Section 4OA5 |
| Date counted | Sep 30, 2012 (2012Q3) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 93800 |
| Inspectors (proximate) | S Graves S Garchow G Miller S Alferink V Gaddya Barrett B Tindell E Uribe B Haga |
| INPO aspect | |
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Finding - River Bend - IR 05000458/2012009 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (River Bend) @ 2012Q3
Self-Identified List (River Bend)
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