05000250/FIN-2016001-01
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Finding | |
|---|---|
| Title | Failure to Fully Implement Procedure QI3-PTN-1, Design Control |
| Description | A self-revealing finding was identified for the licensees failure to provide complete instructions in Maintenance Support Package (MSP)06-053 for the Isophase Bus Enclosure Collar replacement modification in the Turkey Point switchyard. Specifically, the control power circuitry termination points in the 8W43 switchyard breaker were not identified and documented in the associated MSP for removal as required by procedure QI 3-PTN-1, Design Control. As a result, a direct current (DC) ground was introduced to the back-up protection relay by a b contact when the 8W43 breaker was opened during a planned bus switching sequence. The DC ground on the back-up protection circuitry actuated the protection relay and caused both the supply breakers for the Unit 3 startup transformer (SUT) to open resulting in a loss of off-site power (LOOP) for Unit 3. The licensee entered this performance deficiency in their corrective action program (CAP) as action request (AR) 02092653
The performance deficiency was more than minor because it was associated with the procedure quality attribute of the initiating events cornerstone and adversely affected the cornerstone objective to limit the likelihood of events that upset plant stability and challenge critical safety functions during power operations. Specifically, the failure to apply procedure QI 3-PTN-1 in its entirety allowed for a DC ground to be introduced to the DC back-up protection relay circuit resulting in a LOOP. Because this finding caused a LOOP and a resultant loss of residual heat removal (RHR), a detailed risk evaluation was required per IMC-0609, Appendix G, Shutdown Operations Significance Determination Process. A Senior Reactor Analyst assessed the risk significance and concluded it was of very low safety significance (Green). The risk of the event was mitigated by the multiple means that the licensee had available to them to either: 1) restore electrical power to the safety related buses, or; 2) establish alternate means of heat removal either via the steam generators or via primary feed and bleed. The inspectors did not identify a cross-cutting aspect associated with this finding because it was not indicative of current performance since the modification package was implemented greater than three years ago. |
| Site: | Turkey Point  |
|---|---|
| Report | IR 05000250/2016001 Section 4OA3 |
| Date counted | Mar 31, 2016 (2016Q1) |
| Type: | Finding: Green |
| cornerstone | Initiating Events |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71153 |
| Inspectors (proximate) | C Fontana D Mas-Penaranda J Hickman J Patel L Suggs M Endress S Sanchez T Hoeg |
| INPO aspect | |
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Finding - Turkey Point - IR 05000250/2016001 | ||||||||||||||||||||||||||||||
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Finding List (Turkey Point) @ 2016Q1
Self-Identified List (Turkey Point)
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