05000458/LER-2011-002
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| River Bend Station - Unit 1 | |
| Event date: | 02-13-2011 |
|---|---|
| Report date: | 04-14-2011 |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 4582011002R00 - NRC Website | |
- The affected calibration procedure (and the procedures for the redundant channels) will be revised to add instrument mark numbers to the instructions.
- The integrated plant startup procedure has been revised to require the operator to check that this instrumentation is operating properly prior to exceeding 40 percent power.
SAFETY SIGNIFICANCE
The mispositioned valve affected only the "D" main turbine first stage pressure instrument and its associated channel. The logic circuit designs of the RPS system and the reactor recirculation pump trip system are such that the other three redundant channels of main turbine control valve control valve fast closure and main turbine stop valve closure instruments would have caused a reactor scram and/or a recirculation pump trip had such an actual event occurred while the "D" channel was inoperable. Thus, this event was of minimal significance to the health and safety of the public.
(NOTE: Energy Industry Component Identification codes are annotated as (**XX**).)