05000454/FIN-2014005-06
Finding | |
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| Title | Licensee-Identified Violation |
| Description | On February 1, 2014, the licensee identified that vacuum pressures were used to fill RCS piping multiple times since 1998 resulting in RCS system pressures below 0 psig and entered the issue into the CAP process as IR 1625960. Byron TS 3.4.3, RCS Pressure and Temperature Limits, states RCS pressure, RCS temperature, and RCS heatup and cooldown rates shall be maintained within the limits specified i
the PTLR (Pressure Temperature Limits Report.) The PTLR is generated by Westinghouse and contains graphs depicting the acceptable operating ranges of RCS pressure and temperature supported by analysis. The lower bound of these graphs was 0 psig. Byron procedure BOP RC9, Filling an Isolated Reacto Coolant Loop, The Pressurizer, and Drawing a Pressurizer Bubble, was used by the station to fill the loops. This procedure allowed RCS piping pressure to go as low as 28 inches of mercury (approximately14 psig) which is outside the lower bound of the PTLR acceptable region. Procedural controls for the upper bounding limits were appropriate. At the licensees request, Westinghouse performed the additiona analysis needed to expand the lower value of the curves and determined that the lower bounding parameter could be changed to14.7 psig with no impact to the RCS barriers. The analysis was subsequently revised and the PTLR revised to designate the lower boundary accordingly. 10 CFR 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, requires, in part, that activities affecting quality b prescribed by procedures appropriate to the circumstances. Contrary to the above, between April 1998 and October 2013, BOP RC9 allowed RCS pressures to be lower than the analyzed lower bound of the parameter inputs of the PTLR graphs and thus was not appropriate to the circumstances. The finding was more tha minor because it had the potential to adversely impact the Procedure Quality attribute of the Reactor SafetyBarrier Integrity Cornerstone objective to provide reasonable assurance that the RCS design barrier would function to protect the public from radionuclide release caused by accidents or events. Given the analytical conclusion that the condition was acceptable with the new lower boundin parameter, the inspectors determined that there was no change in risk with the issue and the finding was screened as Green. |
| Site: | Byron  |
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| Report | IR 05000454/2014005 Section 4OA7 |
| Date counted | Dec 31, 2014 (2014Q4) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | Licensee-identified |
| Inspection Procedure: | |
| Inspectors (proximate) | C Thompson J Cassidy J Draper J Ellegood J Mcghee M Bielby M Holmberg R Baker R Jickling T Bilik |
| Violation of: | 10 CFR 50 Appendix B Criterion V Technical Specification Technical Specification - Procedures |
| INPO aspect | |
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Finding - Byron - IR 05000454/2014005 | |||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Byron) @ 2014Q4
Self-Identified List (Byron)
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