05000313/FIN-2009005-03
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Finding | |
|---|---|
| Title | Failure to Follow Procedure Led to Loss of Shutdown Cooling |
| Description | The inspectors documented a self-revealing, noncited violation of Technical Specification 6.4.1.a for the licensees failure to follow Operating Procedure OP-1015.008, Unit 2 SDC Control, Revision 30. Specifically, Unit 2 operators did not obtain permission from operations or plant management prior to performing maintenance on any protected train components. In this particular case, both trains of shutdown cooling, and their associated power supplies, were declared protected trains by operations. On September 20, 2009, operations personnel decided to perform an offsite power fast transfer test on the train A and train B vital buses. During the performance of the test on the train A vital bus, a fast transfer relay failed to actuate causing the slow transfer of the bus power supply. This caused the bus to de-energize and caused the inservice shutdown cooling pump to trip. The loss of shut down cooling resulted in a reactor coolant system temperature rise of 5 degrees. The licensee entered this issue into the corrective action program as Condition Report CR-ANO-C-2009-2002. The inspectors determined that the failure of the operations staff to follow Operating Procedure OP-1015.008, Unit 2 SDC Control, Revision 30, was a performance deficiency. Specifically, the Unit 2 operations test team failed to obtain operations manager or plant manager permission prior to performing surveillance testing on the protected systems or equipment. The performance deficiency was determined to be more than minor because it was associated with the human error attribute and adversely affected the Initiating Events Cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown conditions and is therefore a finding. The failure to follow procedures resulted in the loss of the only train of shutdown cooling that was in service. This finding was evaluated for significance using NRC Manual Chapter 0609, Significance Determination Process, Appendix G, Checklist 3, for shutdown operations, and was determined to be of very low safety significance because the core heat removal guidelines associated with instrumentation, training and procedures, and equipment were met. Specifically, both trains of shutdown cooling remained operable with necessary support systems. This finding was determined to have a crosscutting aspect in the area of human performance, associated with decision making H.1(a) in that the licensee failed to make safety-significant or risksignificant decision using a systematic process, especially faced with uncertain or unexpected plant conditions, to ensure safety was maintained. In this case, although the licensee formally defined the authority and roles for decisions affecting nuclear safety, the shift manager and the shift operations manager oversight failed to implement their roles and authorities in deciding to conduct the offsite power transfer test on both protected trains of shutdown cooling (Section 4OA3.1) |
| Site: | Arkansas Nuclear  |
|---|---|
| Report | IR 05000313/2009005 Section 4OA3 |
| Date counted | Dec 31, 2009 (2009Q4) |
| Type: | NCV: Green |
| cornerstone | Initiating Events |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71153 |
| Inspectors (proximate) | A Sanchez G Werner J Clark J Josey M Haire M Shannon N O'Keefe R Azua S Rotton T Farnholtz |
| CCA | H.13, Consistent Process |
| INPO aspect | DM.1 |
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Finding - Arkansas Nuclear - IR 05000313/2009005 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Arkansas Nuclear) @ 2009Q4
Self-Identified List (Arkansas Nuclear)
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