ENS 40605
ENS Event | |
|---|---|
12:46 Mar 23, 2004 | |
| Title | Indication of Crack Failure on Rcs Pressure Boundary Penetration |
| Event Description | Unit 1 is currently in a refueling outage in Mode 5. During a routine inservice inspection of the reactor vessel, an indication was discovered on the N1B penetration. This is associated with the suction for B Loop of Reactor Recirculation. At 0746 on 3/23/2004, the Control Room was notified that the evaluation was completed and the indication was determined to be unacceptable under the ASME Section XI Code. Based on guidance provided in NUREG-1022, Rev. 2, this material defect in the primary coolant boundary constitutes a seriously degraded condition and is reportable under 10CFR50.72(b)(3)(ii)(A). A final evaluation of the flaw and a repair plan is being developed.
The licensee informed the NRC Resident Inspector.
On March 23, 2004, PPL Susquehanna, LLC reported a material defect discovered on the N1B penetration associated with the suction for the B Loop of Reactor Recirculation. The defect was discovered during routine inservice inspection of the reactor vessel. At the time of the report, the indication was believed to exceed the acceptability standards of ASME Section XI, IWB-3640. Accordingly, an ENS call was made pursuant to the reporting requirements of 10CFR50.72(b)(3)(ii)(A). Engineering analysis subsequently determined that the dimensional characteristics of the flaw were within the acceptability requirements of ASME Section Xl. This analysis conclusion provides the basis for retraction of the ENS report of March 23. Although hypothetical flaw growth calculations demonstrated that the flaw size would remain within the allowable envelope of ASME Section Xl, IWB-3641-1 over the next operating cycle, and continued operation without repair of the observed flaw was justified, PPL Susquehanna, LLC performed a weld repair of the defect during the recently completed refueling outage. Notified the R1DO (R. Barkley) |
| Where | |
|---|---|
Susquehanna  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded | |
| Time - Person (Reporting Time:+-1.77 h-0.0738 days <br />-0.0105 weeks <br />-0.00242 months <br />) | |
| Opened: | Grant Fernsler 11:00 Mar 23, 2004 |
| NRC Officer: | Steve Sandin |
| Last Updated: | Apr 29, 2004 |
| 40605 - NRC Website | |
WEEKMONTHYEARENS 564342023-03-26T20:03:00026 March 2023 20:03:00
[Table view]10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition - Leak Rate Limits Exceeded ENS 519872016-06-08T06:26:0008 June 2016 06:26:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Discovery of Unisolable Reactor Pressure Boundary Leakage ENS 519832016-06-06T09:56:0006 June 2016 09:56:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Isolable Leakage Identified from Seal Water Line Weld Inside Rcs Pressure Boundary ENS 515382015-11-13T22:45:00013 November 2015 22:45:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition of Leakage from Pump Lower Seal Weld ENS 509762015-04-11T13:58:00011 April 2015 13:58:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Drywell Leakage Point Identified ENS 506862014-12-13T22:00:00013 December 2014 22:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Reactor Coolant Pressure Boundary ENS 500612014-04-27T03:22:00027 April 2014 03:22:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Minimum Pathway Limit of Msiv Combined Leakage Exceeded During Surveillance Testing ENS 493512013-09-16T18:55:00016 September 2013 18:55:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition Caused by Rhr Relief Valve Leakage ENS 480362012-06-19T21:20:00019 June 2012 21:20:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Mode Change Required by Technical Specifications ENS 478122012-04-06T21:57:0006 April 2012 21:57:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Local Leak Rate Test Results Exceed Pathway Technical Specification Limits ENS 457672010-03-15T13:46:00015 March 2010 13:46:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Secondary Containment Bypass Leakage Exceeded Technical Specification Limit ENS 432252007-03-09T18:45:0009 March 2007 18:45:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Secondary Containment Bypass Leakage Rate Exceeded ENS 424072006-03-12T07:17:00012 March 2006 07:17:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Llrt Test Identified Piping Penetration with Excessive Leakage ENS 415062005-03-21T03:30:00021 March 2005 03:30:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Pressure Boundary Leakage Discovered During Hydro Test ENS 406052004-03-23T12:46:00023 March 2004 12:46:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Indication of Crack Failure on Rcs Pressure Boundary Penetration ENS 405662004-03-04T10:20:0004 March 2004 10:20:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Rcic Steam Supply Failed Llrt 2023-03-26T20:03:00 | |