ENS 46700
ENS Event | |
|---|---|
18:00 Mar 25, 2011 | |
| Title | Both Trains of Emergency Diesel Generators Are Inoperable |
| Event Description | On March 25, 2011, the Train B emergency diesel generator (2EGS-EG2-2) was inoperable and unavailable due to being out of service for scheduled maintenance. At 1400 hours0.0162 days <br />0.389 hours <br />0.00231 weeks <br />5.327e-4 months <br />, the Train A emergency diesel generator (2EGS-EG2-1) was declared inoperable, but available, after questions were raised about the adequacy of the assembly method for fuel injection line compression fittings by the manufacturer. Without assurance that the fittings meet full qualification requirements, the Train A emergency diesel generator was declared inoperable.
The Unit is currently in Mode 6 with fuel loaded and the upper internals installed in the reactor vessel. The reactor vessel head is removed with 23 feet of water in the cavity, two Operable Residual Heat Removal trains one of which is in operation. With both emergency diesels inoperable, the safety functions needed for accident mitigation could be impaired in the event of a loss of off-site power. Actions are currently in progress to restore one emergency diesel generator to an Operable status. This event is reportable pursuant to 10 CFR 50.72(b)(3)(v)(D) due to both emergency diesel generators being inoperable. This event will be evaluated for 10 CFR Part 21 applicability. The licensee is in Technical Specification 3.8.2. With both diesels declared inoperable, they have to suspend all core alterations and possible reactivity additions and return an EDG to service. The licensee plans to return the B train EDG an available status (but not Operable per Technical Specification) by tomorrow. The licensee will then replace the discrepant fuel injector line compression fittings on the A train and return it to Technical Specification Operable status. The licensee has notified the NRC Resident Inspector.
Following replacement of the questionable fuel injection line compression fittings and successful surveillance and post maintenance testing, the Train A emergency Diesel Generator (2EGS-EG2-1) was declared OPERABLE at 0058 hours6.712963e-4 days <br />0.0161 hours <br />9.589947e-5 weeks <br />2.2069e-5 months <br /> on 3/27/2011. One Diesel Generator was maintained available at all times while the issue was being addressed. The licensee notified the NRC Resident Inspector. Notified the R1DO (Rogge). |
| Where | |
|---|---|
Beaver Valley  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident | |
| Time - Person (Reporting Time:+3.58 h0.149 days <br />0.0213 weeks <br />0.0049 months <br />) | |
| Opened: | Daniel Schwer 21:35 Mar 25, 2011 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Mar 27, 2011 |
| 46700 - NRC Website | |