|Entered date||Site||Region||Scram||Reactor type||Event description|
|ENS 54340||21 October 2019 01:23:00||Peach Bottom||NRC Region 1||Manual Scram|
While Unit 3 was shutting down for 3R22 refueling outage, the mode switch was taken to shutdown position which is a manual scram signal. The manual scram signal was not received from the mode switch. A subsequent manual scram was inserted with the use of the manual scram push buttons. The Unit 3 reactor is shutdown with all rods inserted. Unit 2 was unaffected by the event and remains in Mode 1 at 100 percent power. The licensee notified the NRC Resident Inspector, Pennsylvania and Maryland State Agencies, local government. A media press release is planned. Notified DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email), FEMA Region 3 Watch Office (email).
Conditions no longer meet an Emergency Actuation Level and will not deteriorate. Unit 3 reactor is shutdown with all control rods fully inserted. The NOUE was terminated at 0230 EDT." The licensee notified the NRC Resident Inspector, Pennsylvania and Maryland State Agencies, local government. Notified the R1DO (Jackson), NRR EO (Miller), IRDMOC (Gott), R1RA (Lew via email), NRR (Nieh via email), DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email), FEMA Region 3 Watch Office (email).
|ENS 53630||30 September 2018 15:29:00||Peach Bottom||NRC Region 1||Automatic Scram||On Sunday, September 30, 2018, at 1130 EDT, an automatic scram was received on U3 following a loss of two condensate pumps. Following the reactor scram, water level lowered from normal level of 23" to below 1" which resulted in automatic Group II and Group III isolations. Reactor water level lowered to -48" which resulted in initiation of the High Pressure Coolant Injection and Reactor Core Isolation Cooling systems. Reactor water level and reactor pressure have been restored to their normal bands. All systems responded properly to the event. Unit 3 remains in Mode 3 with reactor pressure being controlled on the turbine bypass valves. The cause and details of the event are under investigation. This report is being made in accordance with 10 CFR 50.72(b)(2)(iv)(A), 10 CFR 50.72(b)(2)(iv)(B), and 10 CFR 50.72(b)(3)(iv)(A). All control rods inserted. Decay heat is being removed via the main condenser. The NRC Resident Inspector has been notified. A notification to the media and a press release were made. Unit 2 was unaffected and continues coastdown to refueling.|
|ENS 45348||14 September 2009 01:49:00||Peach Bottom||NRC Region 1||Manual Scram|
|GE-4||During the scheduled shutdown to commence the Peach Bottom Unit 3 refueling outage, Unit 3 was manually shutdown using the mode switch in accordance with GP-3, 'Normal Plant Shutdown,' when reactor period lowered below 50 seconds as indicated on the WRNM (Wide Range Nuclear Monitoring) system. The Feedwater Startup Level Controller was in automatic set at 23" when a small addition of cold water added enough positive reactivity to cause reactor period to be less than 50 seconds. The shortest period observed was 44 seconds. The WRNM system RPS (Reactor Protective System) automatic SCRAM setpoint is 19 seconds. All control rods inserted into the core. Decay heat is being removed by shutdown cooling. The plant is continuing into its scheduled refueling outage. The licensee notified the NRC Resident Inspector.|
|ENS 42889||7 October 2006 23:49:00||Peach Bottom||NRC Region 1||Manual Scram||GE-4||At 17:50, on 10/07/2006, the Peach Bottom Atomic Power Station identified a crack approximately 4 inches long on a Unit 2, Reactor Core Isolation Cooling (RCIC) test line, as the line penetrates the Suppression Pool of Primary Containment. The degraded piping represents a loss of primary containment integrity, placing one of the principle safety barriers in a 'Seriously Degraded' condition as defined by 10CFR50.72 (b)(3)(ii)(A). This condition required a Reactor Shutdown per the plants Technical Specifications (TS) (TS 22.214.171.124). Unit 2 was manually scrammed, at 20:16, in order to shutdown the reactor and place the unit in Mode 3 per the Technical Specifications. The TS required shutdown is reportable per 10CFR50.72(b)(2)(i). The unplanned reactor scram is reportable per 10CFR50.72(b)(2)(iv)(B). The reactor scram and resultant Emergency Safety Feature actuations were completed as required. In addition, the loss of primary containment integrity represents a condition that 'could have prevented the fulfillment of a safety function of a structure required to control the release of radioactive material' and/or 'mitigate the consequences of an accident.' This is reportable per 10CFR50.72(b)(3)(v)(C) and (D). Unit 2 is currently shutdown, Mode 3, with an RPV cooldown in progress, with plans to Enter Mode 4 by 02:00 on 10/08/06. All control rods fully inserted on the Manual Reactor Scram. The reactor is currently being fed from the condensate system with decay heat being removed to the condenser via the MSL drains. The electric plant is in a normal shutdown lineup. See EN # 42887 for related NOTICE OF UNUSUAL EVENT. Additional 10 CFR Section not listed above: 50.72(b)(3)(v)(D) ACCIDENT MITIGATION The licensee notified the NRC Resident Inspector.|
|ENS 40537||22 February 2004 18:42:00||Peach Bottom||NRC Region 1||Manual Scram|
|GE-4||Peach Bottom Unit 2 reactor was manually scrammed due to degrading main condenser vacuum. The reactor was manually scrammed prior to reaching the automatic scram setpoint. All plant systems responded as expected with no significant issues noted. A Group II and Group III Primary Containment Isolation was received due to reactor water level passing through 1 inch. All isolation systems responded as required and repositioned to their expected positions. The licensee also indicated that all control rods properly inserted into the core. The method of decay heat removal was using the main condenser. The licensee initiated a post scram review to identify and correct the source of degrading vacuum. The licensee also indicated the manual scram was initiated at 25 inches and lowering of condenser vacuum. The licensee notified the NRC Resident Inspector.|