05000313/FIN-2012004-01
From kanterella
Jump to navigation
Jump to search
Finding | |
---|---|
Title | Failure to Promptly Identify and Correct a Condition Adverse to Quality with the Unit 2 Vital Inverters |
Description | The inspectors identified a non-cited violation of 10 CFR Part 50, Appendix B, Criterion XVI, Corrective Action, for the licensees failure to promptly identify and correct a condition adverse to quality associated with the Unit 2 vital inverters. Specifically, in 2010 the licensee failed to identify and correct the cause for a fuse failure and subsequent failure of vital inverters to start that allowed the condition to reoccur in 2011 and 2012. The licensee has placed the issue into their corrective action program as Condition Report CR-ANO-2-2012-0748. The inspectors determined that the failure to promptly identify and correct a condition adverse to quality associated with the Unit 2 vital inverters is a performance deficiency. Specifically, the licensee failed to identify the cause of the fuse failures and take effective corrective actions in 2010, resulting in the failures in 2011 and 2012. The performance deficiency was more than minor because it was associated with the equipment performance attribute of the Mitigating Systems Cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability and capability of systems that respond to initiating events to prevent undesirable consequences and is therefore a finding. Using Manual Chapter 0609, Attachment 4 Initial Characterization of Findings, and Appendix A, The Significance Determination Process for Findings at Power the finding was determined to have very low safety significance, Green, because: (1) the finding was a deficiency affecting the design of a mitigating SSC and SSC operability was not maintained, (2) it did not represent a loss of system and/or function, (3) it did not represent an actual loss of function of a single train for greater than its technical specification allowed outage time, (4) it did not represent an actual loss of function of one or more non-technical specification trains of equipment designated as high safety-significant in accordance with the licensees maintenance rule program for greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and (5) it did not involve the loss or degradation of equipment or function specifically designed to mitigate a seismic, flooding, or severe weather event. The finding was determined to have a cross-cutting aspect in the area of human performance, associated with decision making, in that the licensee failed to use conservative assumptions in decision making and failed to verify the validity of the underlying assumptions during effectiveness reviews. Specifically, the licensee assumption that the constant voltage transformer was the cause of the fuse failures was not valid and the condition report closure review accepted the assumption with contrary evidence that the transformer was satisfactory |
Site: | Arkansas Nuclear ![]() |
---|---|
Report | IR 05000313/2012004 Section 1R19 |
Date counted | Sep 30, 2012 (2012Q3) |
Type: | NCV: Green |
cornerstone | Mitigating Systems |
Identified by: | NRC identified |
Inspection Procedure: | IP 71111.19 |
Inspectors (proximate) | A Sanchez D Allen G Guerra J Laughlin J Rotton L Carson W Schaup |
CCA | H.14, Conservative Bias |
INPO aspect | DM.2 |
' | |
Finding - Arkansas Nuclear - IR 05000313/2012004 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Finding List (Arkansas Nuclear) @ 2012Q3
Self-Identified List (Arkansas Nuclear)
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||