ENS Event | |
|---|---|
20:00 May 31, 2015 | |
| Title | Technical Specification Required Shutdown Due to Failure of an Emergency Diesel Generator |
| Event Description | At 1600 [EDT] on May 31, 2015, [DC Cook] operations commenced a shutdown of DC Cook Unit 1 to comply with LCO 3.8.1 Condition G, when the 14 day limit to complete Condition B Required Action could not be met.
At 0010 [EDT] on May 18, 2015, Unit 1 AB Emergency Diesel Generator was removed from service for planned maintenance. LCO 3.8.1 Condition B was entered which allows 14 days to restore diesel to operable. At 1049 [EDT] on May 21, 2015, Unit 1 AB Emergency Diesel Generator tripped during post maintenance testing due to high bearing temperatures. Subsequent actions to repair and restore the diesel to operable status have been unsuccessful. This event is reportable under 10 CFR 50.72(b)(2)(i), the initiation of any nuclear plant shutdown required by the plant's Technical Specifications, as a four (4) hour report. The DC Cook Sr. Resident NRC Inspector has been notified. Unit 1 is expected to be in Mode 5 by 2030 EDT on June 1, 2015. There is no impact on Unit 2.
This update is to correct the information contained in the block titled 'Power/Mode After'. The power and mode after the event requiring notification (TECHNICAL SPECIFICATION REQUIRED SHUTDOWN DUE TO INABILITY TO RESTORE UNIT 1 AB EDG WITHIN THE COMPLETION TIME PRESCRIBED IN LCO 3.8.1 CONDITION B) was 99% power and mode 1. The licensee has notified the NRC Resident Inspector. D.C. Cook Unit 1 is currently in Mode 3 and conducting a normal cooldown to Mode 4. Notified R3DO (Passehl).
DC Cook Unit 1 reactor was shut down (Mode 3) at 0231 hours0.00267 days <br />0.0642 hours <br />3.819444e-4 weeks <br />8.78955e-5 months <br /> [EDT] June 01, 2015 and achieved Mode 5 at 0410 hours0.00475 days <br />0.114 hours <br />6.779101e-4 weeks <br />1.56005e-4 months <br /> [EDT] June 02, 2015 to comply with LCO 3.8.1 Condition G with all systems operating normally. The licensee has notified the NRC Resident Inspector. Notified R3DO (Passehl). |
| Where | |
|---|---|
Cook  Michigan (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown | |
| LER: | 05000315/LER-2015-001 |
| Time - Person (Reporting Time:+-3.47 h-0.145 days <br />-0.0207 weeks <br />-0.00475 months <br />) | |
| Opened: | Richard Harris 16:32 May 31, 2015 |
| NRC Officer: | Mark Abramovitz |
| Last Updated: | Jun 2, 2015 |
| 51106 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (99 %) |
WEEKMONTHYEARENS 546872020-05-01T07:54:0001 May 2020 07:54:00
[Table view]10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Reactor Coolant System Pressure Boundary Leakage ENS 511062015-05-31T20:00:00031 May 2015 20:00:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Failure of an Emergency Diesel Generator ENS 510042015-04-23T06:10:00023 April 2015 06:10:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Manual Reactor Trip Due to a Secondary Plant Transient ENS 481202012-07-19T19:30:00019 July 2012 19:30:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Tech Spec Required Shutdown Due to Inability to Restore Main Steam Isolation Automatic Actuation Logic and Actuation Relays within the Required Time ENS 427392006-07-30T11:30:00030 July 2006 11:30:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Shutdown for High Containment Air Temperature 2020-05-01T07:54:00 | |