ENS 56936
ENS Event | |
|---|---|
17:02 Jan 29, 2024 | |
| Title | Automatic Reactor Scram |
| Event Description | The following information was provided by the licensee via email:
At approximately 1202 EST on 01/29/24, unit 2 experienced a reactor scram caused by a main turbine trip. Investigation is still ongoing. The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance: All control rods were fully inserted. The licensee indicated that the turbine trip may have been caused by a power load imbalance, however the cause of the incident is under investigation. The scram was not complex. Decay heat is currently being removed thru bypass valves dumping to the main condenser. Initially unit 2 lost the use of the bypass valves due to lack of condenser vacuum. Unit 2 used the high pressure coolant injection (HPCI) system in the condenser storage tank (CST) to CST mode to remove decay heat. Residual heat removal was used to keep the torus cool. Condenser vacuum was regained and unit 2 is back to removing decay heat with the turbine bypass valves. There was no impact to unit 3. The licensee confirmed there was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
The following information was provided by the licensee via email: Licensee adds 8-hour non-emergency 10 CFR 50.72(b)(3)(iv)(A) specified system actuation report to original 4-hour non-emergency 10 CFR 50.72(b)(2)(iv)(B) RPS Actuation report. At approximately 1202 EST on 01/29/24, unit 2 experienced a reactor scram by a main turbine trip. All control rods inserted. Reactor core isolation cooling system (RCIC) was manually initiated for level control. HPCI was manually initiated for pressure control. Primary containment isolation system (PCIS) Group II and III isolations occurred [specified system actuation]. Investigation is ongoing. The NRC Resident Inspector has been notified. |
| Where | |
|---|---|
Peach Bottom  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(2)(iv)(B), RPS Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation | |
| LER: | 05000277/LER-2024-001 Submittal of LER 2024-001-00 for Peach Bottom Atomic Power Station (PBAPS) Unit 2 Automatic Reactor Scram Due to an Invalid Generator Lockout |
| Time - Person (Reporting Time:+-3.5 h-0.146 days <br />-0.0208 weeks <br />-0.00479 months <br />) | |
| Opened: | Eli Digon 13:32 Jan 29, 2024 |
| NRC Officer: | Natalie Starfish |
| Last Updated: | Feb 1, 2024 |
| 56936 - NRC Website
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Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | A/R |
| Before | Power Operation (100 %) |
| After | Hot Shutdown (0 %) |
Peach Bottom with 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation | |
WEEKMONTHYEARENS 572212024-07-10T11:28:00010 July 2024 11:28:00
[Table view]10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram Due to Manual Turbine Trip ENS 569362024-01-29T17:02:00029 January 2024 17:02:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram ENS 558992022-05-16T19:52:00016 May 2022 19:52:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Scram Due to Electrical Transients ENS 555752021-11-14T10:25:00014 November 2021 10:25:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Trip Due to Lowering Main Condenser Vacuum ENS 536302018-09-30T04:00:00030 September 2018 04:00:00 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)(iv)(A), System Actuation - ECCS Discharge Automatic Scram Due to a Loss of Two Condensate Pumps ENS 472862011-09-21T14:20:00021 September 2011 14:20:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Relay Malfunction Resulted in a Valid Undervoltage Signal ENS 453482009-09-14T02:44:00014 September 2009 02:44:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram Due to Short Period During Plant Shutdown ENS 428892006-10-07T21:50:0007 October 2006 21:50:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded, 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material Technical Specification Required Shutdown Due to Loss of Primary Containment Integrity ENS 418322005-07-10T07:18:00010 July 2005 07:18:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Turbine Trip Resulting in Rps Actuation and Automatic Reactor Scram ENS 412772004-12-22T09:55:00022 December 2004 09:55:00 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)(iv)(A), System Actuation - ECCS Discharge Reactor Scram and Eccs Injection Following Opening of Turbine Bypass Valves ENS 405372004-02-22T20:10:00022 February 2004 20:10:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Scram at Peach Bottom 2 Due to Decreasing Condenser Vacuum ENS 401982003-09-25T04:00:00025 September 2003 04:00:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.73(a)(1), Submit an LER Initiation of a Technical Specification Required Shutdown at Peach Bottom 2 2024-07-10T11:28:00 | |