05000387/FIN-2011002-06
From kanterella
Jump to navigation
Jump to search
Finding | |
|---|---|
| Title | None |
| Description | On January 25, 2011, PPL commenced maintenance on the U2 RHR swing bus transfer switch, which resulted in the entire loop of RHR being inoperable due to a loss of power to the associated loads powered by the swing bus. Although the impacts were understood by Operations personnel and the appropriate Technical Specification (TS) LCO was entered, an additional clearance for status control was applied without the Work Week Manager\'s awareness that rendered the B RHR loop unavailable. When the RHR loop was included in the risk assessme4t, it was determined that plant risk was Yellow, previously calculated and communicated to the station as Green. This issue was determined to be a violation of 10 CFR 50.65 (aX4), for failure to ensure work was properly modeled and evaluated for online plant risk. This finding is more than minor because it is similar to example 7.e. in NRC IMC 0612 Appendix E, Examples of Minor lssues. This example states, in part, that failure to perform an adequate risk assessment when required by 10 CFR 50.65 (aX4) is not minor if the overall elevated plant risk would put the plant into a higher licensee established risk category. This finding was evaluated using IMC 0609, Appendix K, Maintenance Risk Assessment and Risk Management Significance Determination Process. In accordance with flow chart 1, the finding was determined to be Green since the risk deficit did not exceed the threshold for incremental core damage probability or incremental large early release probability. The issue was entered into PPL\'s CAP as CR 1347508. |
| Site: | Susquehanna  |
|---|---|
| Report | IR 05000387/2011002 Section 4OA7 |
| Date counted | Mar 31, 2011 (2011Q1) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | Licensee-identified |
| Inspection Procedure: | |
| Inspectors (proximate) | E Dipaolo J Furia A Rosebrook P Finney J Tomlinson J Greives D Molteni |
| INPO aspect | |
| ' | |
Finding - Susquehanna - IR 05000387/2011002 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Finding List (Susquehanna) @ 2011Q1
Self-Identified List (Susquehanna)
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||