05000387/FIN-2013002-02
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Finding | |
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| Title | Inadequate Restoration from Clearance Order Results in Degradation of Main Condenser Vacuum and Plant Downpower |
| Description | A self-revealing NCV of very low safety significance (Green) was identified when PPL incorrectly implemented the clearance order process while returning the common offgas recombiner to service after maintenance. NDAP-QA-0322, Energy Control Process, Revision 42, requires that upon completion of the [clearance order] restoration plan, the system should be restored to the design operating condition (e.g. running, automatic standby, etc.). Additionally, it requires the System Operating Representative (SOR) and Operations Supervision to ensure restoration of the clearance order prevents introduction of system or plant transients. Contrary to these requirements, on December 12, 2012, when restoring from a clearance order, a manual isolation valve for the common recombiner was incorrectly left in the closed position. This resulted in a degradation of main condenser vacuum when the common recombiner was subsequently placed in service on February 5, 2013, requiring operator action to decrease reactor power to maintain main condenser vacuum within limits. PPL entered the issue into the CAP as CR 1668013. The performance deficiency is more than minor because it was associated with the Configuration Control attribute of the Initiating Events cornerstone and affected the cornerstone objective to limit the likelihood of events that upset plant stability and challenge critical safety functions during power operations. Specifically, when PPL operators attempted to place the common recombiner in service on February 5, 2013, the closed manual isolation valve caused a loss of process flow to the recombiner and ultimately a degradation of main condenser vacuum. In responding to the reduction in vacuum, a recirculation pump runback was initiated and thermal power was rapidly reduced by approximately 32 percent. Additionally, the performance deficiency was similar to example 4.b in IMC 0612, Appendix E, Examples of Minor Issues, which states that a procedural error is more than minor if it caused a reactor trip or other transient. The inspectors evaluated the finding using IMC 0609, Appendix A, The Significance Determination Process (SDP) for Findings At-Power, and determined the finding did not cause a reactor trip and the loss of mitigation equipment relied upon to transition the plant from the onset of the trip to a stable shutdown condition. Consequently, the finding is of very low safety significance (Green). The finding is related to the cross-cutting area of Human Performance, Work Practices in that PPL did not communicate human error prevention techniques such as self and peer checking to ensure work activities are performed safely. Specifically, both the SOR and Operations Supervision reviews were insufficient to ensure the manual steam isolation valve for the common recombiner was restored to the correct position during clearance order removal. |
| Site: | Susquehanna  |
|---|---|
| Report | IR 05000387/2013002 Section 1R13 |
| Date counted | Mar 31, 2013 (2013Q1) |
| Type: | NCV: Green |
| cornerstone | Initiating Events |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71111.13 |
| Inspectors (proximate) | P Kaufman M Gray F Arner P Finney J Ayala J Greives C Lally |
| Violation of: | Technical Specification - Procedures |
| CCA | H.12, Avoid Complacency |
| INPO aspect | QA.4 |
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Finding - Susquehanna - IR 05000387/2013002 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Susquehanna) @ 2013Q1
Self-Identified List (Susquehanna)
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