ENS Event | |
|---|---|
05:00 Aug 27, 2022 | |
| Title | Part 21 - Service Water Booster Pump Bearing Housing Cover Oil Leak |
| Event Description | The following information was provided by the licensee via phone and email:
On August 27, 2022, while in Mode 1 at 100 percent power, Nebraska Public Power District (NPPD) Cooper Nuclear Station (CNS) identified a 3 drops per minute (dpm) oil leak from the radial (inboard) bearing housing cover on one of four residual heat removal (RHR) service water booster pumps (SWBP); specifically, SWBP-D. Subsequent analysis determined that the leak was a result of a deviation with the configuration of the labyrinth seal drain path. This deviation was due to an error introduced in a manufacturing drawing used by the vendor for the fabrication of four new replacement pumps. The bearing housing cover is a unique design to CNS for the RHR SWBPs. On March 1, 2024, NPPD completed a substantial safety hazard evaluation and determined that the manufacturing drawing error could cause a substantial safety hazard. The NRC Resident Senior Resident has been notified. This is a non-emergency notification required by 10 CFR 21.21(d)(3)(i). A written notification will be provided within 30 days. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: All four SWBPs had a similar housing design. Three of the four pump housings have been replaced. No other nuclear plant is affected due to the housing design being unique to CNS. |
| Where | |
|---|---|
Cooper  Brownville, Nebraska (NRC Region 4) | |
| Organization: | Cooper Nuclear Station |
| Reporting | |
| 10 CFR 21.21(d)(3)(i), Failure to Comply or Defect | |
| Time - Person (Reporting Time:+13255.83 h552.326 days <br />78.904 weeks <br />18.158 months <br />) | |
| Opened: | Linda Dewhirst 13:50 Mar 1, 2024 |
| NRC Officer: | Sam Colvard |
| Last Updated: | Mar 1, 2024 |
| 57001 - NRC Website
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WEEKMONTHYEARENS 577702025-05-22T05:00:00022 May 2025 05:00:00
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