05000454/FIN-2011002-07
From kanterella
Jump to navigation
Jump to search
Finding | |
|---|---|
| Title | Licensee-Identified Violation |
| Description | A finding of very low safety significance (Green) and associated NCV of 10 CFR Part 50, Appendix B, Criterion III, Design Control, was identified by the licensee for the failure to account for vortexing when determining the maximum available time to isolate flow from the containment spray additive tank. Specifically, the applicable calculation assumed that nitrogen would enter the system when the tank was completely drained. The performance deficiency was determined to be more than minor because it was associated with the Barrier Integrity cornerstone attribute of Structures, Systems, Components, and Barrier Performance and adversely affected the cornerstone objective of providing reasonable assurance that physical design barriers protect the public from radionuclide releases caused by accidents or events. The finding screened as having very low safety significance because it was a design deficiency of the physical integrity of the reactor containment that did not: (1) affect the barrier function of the control room against smoke or a toxic atmosphere; (2) represent an actual open pathway in the physical integrity of reactor containment; and (3) involve an actual reduction in function of hydrogen igniters in the reactor containment. The licensee entered this concern in their corrective action program as IR 1148711 to track the completion of a vortexing calculation. The licensee also performed preliminary calculations that determined there was margin between the time the low level setpoint was reached and the time the tank outlet valves were isolated. In addition, alarm and emergency procedures directed the operators to close isolation valves to prevent gas intrusion. |
| Site: | Byron  |
|---|---|
| Report | IR 05000454/2011002 Section 4OA7 |
| Date counted | Mar 31, 2011 (2011Q1) |
| Type: | NCV: Green |
| cornerstone | Barrier Integrity |
| Identified by: | Licensee-identified |
| Inspection Procedure: | |
| Inspectors (proximate) | R Ng C Thompson B Bartlett J Robbins J Cassidy M Jones E Duncan J Gilliam W Lyon C Tilton J Miller J Whitman |
| INPO aspect | |
| ' | |
Finding - Byron - IR 05000454/2011002 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Finding List (Byron) @ 2011Q1
Self-Identified List (Byron)
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||