Inadequate Maintenance Procedure Results in a Reactor Trip
A self-revealing finding of very low safety significance was identified when Entergy personnel did not use a procedure appropriate to the task for testing of a secondary plant valve, resulting in a transient that led to a manual reactor trip. On February 13, 2013, with Unit 2 at full power, Entergy personnel started testing of a heater drain tank dump valve without electrical isolation and other risk management precautions. When energized control power leads were lifted as specified in the work instruction, two electrically inter-connected valves opened causing loss of heater drain flow to the main feedwater pumps. The transient affected steam generator level and operators initiated a rapid down power followed by a manual reactor trip when steam generator level control limits were challenged. The transient was documented in their corrective action program (CAP) as CR-IP2-2013-721. The finding was more than minor because the testing activity resulted in a reactor trip. The inspectors performed a Phase 1 screening in accordance with IMC 0609, Significance Determination Process and determined the finding to be of very low safety significance (Green) because all mitigating equipment remained available. The finding had a crosscutting aspect in the area of Human Performance, Resources, because the licensee did not assure that procedures and other resources were available and adequate to assure nuclear safety, including accurate design documentation and procedures to support the work activity. Specifically, the work instruction used for the testing had not been appropriately planned or implemented when the electrical control power ties to valves outside the work scope was neither planned into the work nor recognized by the workers.
|Report||IR 05000247/2013002 Section 1R12|
|Date counted||Mar 31, 2013 (2013Q1)|
|Inspection Procedure:||IP 71111.12|
|Inspectors (proximate)||A Burritt|
Finding List (Indian Point) @ 2013Q1
Self-Identified List (Indian Point)