ENS 47454
From kanterella
Jump to navigation
Jump to search
ENS Event | |
|---|---|
20:15 Nov 17, 2011 | |
| Title | Technical Specification Required Shutdown Due to Inoperable Feedwater Check Valve |
| Event Description | On Thursday, November 17, 2011, at 1515 hours0.0175 days <br />0.421 hours <br />0.0025 weeks <br />5.764575e-4 months <br />, with the reactor at approximately 50% core thermal power, the station entered a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> cold shutdown action statement due to the inability to provide a manual isolation for a main feedwater line check valve that had been declared inoperable due to a leak. As background, the reactor was at reduced power in order to perform a planned main condenser thermal backwash. While at reduced power an inspection of the main steam tunnel (a normally locked closed high radiation area) was performed as part of a scheduled system inspection. The inspection identified a leak on the feedwater line 'B' outboard check valve (6-CK-62B). The feedwater check valve was declared inoperable and the Limiting Condition for Operation (LCO) for Technical Specification (TS) 3.7.A.2.a.5 was entered. Because there is no ability to manually isolate the primary containment penetration the station is required to be in cold shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> per TS 3.7.A.5.
Currently, preparations are being completed to conduct the reactor shutdown and to initiate check valve repairs. This event had no impact on the health and safety of the public. The USNRC Senior Resident Inspector was onsite and has been notified. The electrical lineup is normal and all safety related equipment required for shutdown and cooldown are operable. |
| Where | |
|---|---|
| Pilgrim Massachusetts (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown | |
| Time - Person (Reporting Time:+-2.25 h-0.0938 days <br />-0.0134 weeks <br />-0.00308 months <br />) | |
| Opened: | Mert Probasco 18:00 Nov 17, 2011 |
| NRC Officer: | Joe O'Hara |
| Last Updated: | Nov 17, 2011 |
| 47454 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (50 %) |
| After | Power Operation (50 %) |
Pilgrim with 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown | |
WEEKMONTHYEARENS 486852013-01-21T01:50:00021 January 2013 01:50:00
[Table view]10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification (Ts) Required Shutdown - Safety Relief Valve Declared Inoperable ENS 475532011-12-26T17:50:00026 December 2011 17:50:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown - Safety Relief Valve Declared Inoperable ENS 474542011-11-17T20:15:00017 November 2011 20:15:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Inoperable Feedwater Check Valve ENS 468522011-05-14T06:45:00014 May 2011 06:45:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Inability to Maintain Specified Differential Pressure Between Drywell and Suppression Chamber ENS 466282011-02-20T05:00:00020 February 2011 05:00:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown-Reactor Building Closed Cooling Water Train Inoperable 2013-01-21T01:50:00 | |
Retrieved from "https://kanterella.com/w/index.php?title=ENS_47454&oldid=424232"